2024-03-29T11:27:29Z
https://journal.ugm.ac.id/index/oai
oai:jurnal.ugm.ac.id:article/547
2017-03-01T05:51:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/547
2017-03-01T05:51:18Z
Jurnal Rekayasa Proses
Vol 2, No 1 (2008); 1-4
Kesetimbangan Natrium di Dalam Campuran Biodiesel Gliserol
Supriyono,
Wijayanti, Kurnia
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/547
Transesterifikasi adalah salah satu cara yang ditempuh didalam pembuatan biodiesel. Proses ini menggunakan katalisator NaOH. Keberadaan ion Na+ didalam produk biodiesel dapat mengganggu kinerja mesin karena menimbulkan kerak yang menyumbat nozzle dari sistem pembakaran, dengan alasan ini kandungan maksimal Na+ oleh Uni Eropa dibatasi sejumlah 5 mg/kg biodiesel. Penggunaan NaOH sebagai katalisator transesterifikasi lebih banyak difokuskan pada tujuan pencapaian konversi reaksi tertinggi yang dapat dicapai, sedangkan Na+ yang terikut pada produk biodiesel belum mendapatkan perhatian yang cukup. Penelitian dilakukan dengan mereaksikan minyak jarak pagar dengan metanol sebanyak 3 kali kebutuhan stoikiometrisnya di dalam labu leher tiga yang dilengkapi dengan kondenser, sedangkan sebagai katalisator digunakan NaOH. Hasil reaksi akan membentuk dua fasa yaitu gliserol dan biodiesel. Selanjutnya kandungan Na+ pada tiap fasa dianalisis. Hasil penelitian ini menunjukkan apabila ditinjau dari sisi thermodinamika dengan tinjauan melalui excess Gibbs free energy , maka konsentrasi maksimal NaOH yang boleh digunakan untuk transesterifikasi minyak biji jarak adalah sebesar 0,0015% berat minyak.
Kata kunci: Transesterifikasi, kelarutan, NaOH, excess gibbs free energy
Transesterification is one of the processes for producing biodiesel. The process involves the use of liquid catalyst such as NaOH. However, the presence of Na+ ions in biodiesel accelerates the scale formation and aggravates the combustion engine performance. Therefore, the maximum concentration of Na+ is about 5 mg / kg biodiesel to minimize the effect. Recently, the focus study of transesterification using NaOH as a catalyst is achieving higher conversion. Meanwhile, the reduction process of Na+ remaining in the biodiesel has not yet been studied. The experiments were carried out in a three-neck flask equipped with a reflux condenser where jatropha oil was reacted with methanol. The amount of methanol was 3 times of the stoichiometric molar ratio, while NaOH was used as catalyst. The concentration of Na+ both in the glycerol and biodiesel phases were analyzed. Based on the excess Gibbs free energy, the maximum concentration of NaOH for transesterification of Jatropha oil was 0.0015% weight.
Key words: Transesterification, solubility, NaOH, excess Gibbs free energy
oai:jurnal.ugm.ac.id:article/548
2017-03-01T05:51:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/548
2017-03-01T05:51:18Z
Jurnal Rekayasa Proses
Vol 2, No 1 (2008); 5-9
Pengaruh Konsentrasi Katalisator dan Rasio Bahan terhadap Kualitas Biodiesel dari Minyak Kelapa
Astuti, Erna
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/548
Kebutuhan energi di Indonesia dari tahun ke tahun semakin meningkat. Oleh karena itu perlu pengembangan energi alternatif , salah satunya adalah biodiesel. Indonesia sebagai negara penghasil minyak nabati terbesar dunia, juga sebagai negara penghasil minyak kelapa relatif besar dunia mempunyai peluang untuk menghasilkan dan memainkan peranan penting dalam produksi bahan bakar biodiesel. Di antara berbagai jenis minyak nabati, minyak kelapa mempunyai peluang besar untuk digunakan sebagai bahan baku dalam pembuatan biodisel. Penelitian dilakukan dalam labu leher tiga yang dilengkapi motor pengaduk dan termometer. Reaksi transesterifikasi diawali dengan mencampur minyak kelapa yang telah dipanaskan dengan campuran etanol dan katalisator KOH. Reaksi dilakukan selama dua jam dengan variabel proses konsentrasi katalisator 0,65 – 0,95 % b/v dan rasio minyak kelapa/etanol antara 2:1 dan 6:1. Kemudian dilakukan pemisahan biodiesel dari gliserol dan pengeringan. Selanjutnya dilakukan uji sifat biodiesel rapat massa, viskositas, cloud point, flash point dan angka asam. Hasil penelitian menunjukkan bahwa hasil minyak destilat yang relatif baik dan yang masuk dalam spesifikasi standar dan mutu biodiesel diperoleh pada pada konsentrasi katalisator KOH 0,75 – 0,90 %b/v dan rasio minyak kelapa/etanol 3:1 – 5:1.
Kata kunci: energi alternatif, biodiesel, transesterifikasi, rasio bahan, standar mutu
The demand for energy in Indonesia has increased very fast in the recent years in the midst of fossil oil depletion. A lot of effort has been carried out to find alternative energies. One of the promising alternative energies is biodiesel. Indonesia, as the largest producer of vegetable oil in the world, has an opportunity to play a significant role as a biodiesel producer. Among various vegetable oils, coconut oil is a potential raw material in biodiesel production. The process was carried out in a three-neck round bottom flask equipped with motor stirrer and thermometer. The trans-esterification reaction was conducted by mixing heated coconut oil with a mixture of ethanol and KOH catalyst for two hours. The process variables studied in the present work were catalyst concentration and coconut oil – ethanol ratio. At the optimal condition when the KOH concentration in a range of 0.75-0.90% w/v and a coconut oil – ethanol ratio of 3:1 -5:1, the process produce biodiesel that meets the standard.
Key words: alternative energy, biodiesel, trans-esterification, reactant ratio, quality assurance
oai:jurnal.ugm.ac.id:article/549
2017-03-01T05:51:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/549
2017-03-01T05:51:18Z
Jurnal Rekayasa Proses
Vol 2, No 1 (2008); 10-15
Pengaruh Konsentrasi dan Jenis Larutan Perendaman terhadap Kecepatan Ekstraksi dan Sifat Gel Agar-agar dari Rumput Laut Gracilaria verrucosa
Distantina, Sperisa
Anggraeni, Devinta Rachmawati
Fitri, Lidya Eka
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/549
Rumput laut jenis Gracilaria penghasil agar-agar banyak tumbuh di Indonesia, tetapi studi pengolahannya belum banyak. Penelitian ini bertujuan mempelajari proses transfer massa pada ekstraksi agar-agar dari rumput laut Gracilaria verucosa (pantai Pekalongan) secara bacth menggunakan pelarut air. Pengaruh penggunaan alkali NaOH (1,5 N dan 3,75 N) dan asam asetat (0,2 N, 0,6 N, dan 0,8 N) pada tahap perendaman terhadap koefisien transfer massa (kca) dan sifat gel agar-agar (gel strength, melting dan setting temperature) juga dipelajari. Rumput laut direndam menggunakan larutan alkali atau asam selama 15 menit. Setelah dicuci menggunakan air sampai pH netral, rumput laut diekstraksi menggunakan pelarut air. Ekstraksi dijalankan di dalam gelas beker yang dilengkapi motor pengaduk. Cuplikan sampel diambil setiap interval waktu tertentu. Cuplikan dibekukan semalam dalam freezer, kemudian diangin-anginkan sehingga air mencair dan terpisah dari agar-agar. Agar-agar yang dihasilkan dikeringkan mengunakan oven (70C) sampai berat konstan. Hasil penelitian menunjukkan bahwa perendaman dengan alkali menghasilkan kecepatan ekstraksi yang lebih lambat, rendemen lebih rendah tetapi sifat gel agar-agar yang lebih baik dibandingkan perendaman menggunakan larutan asam.
Kata kunci: Alkali, Asam Asetat, Perendaman, Ekstraksi, kca
Seaweeds of Gracilaria species are abundantly cultivated in Indonesia. However, studies related to its extraction process are still rare. In the present work, the mass transfer process on a batch extraction of agar was studied by extracting seaweeds in hot water solvent. The effect of alkali (NaOH) and acetic acid (CH3COOH) in the soaking process on the volumetric mass transfer coefficient (kca) and the quality of gel agar were investigated. Seaweeds (Gracilaria verrucosa) from Pekalongan coast were soaked in aqueous NaOH (1.5 N and 3.75 N) or in aqueous acetic acid solution (0.2 N, 0.6 N, and 0.8 N). After being washed, the seaweeds were extracted in hot water of 98C and neutral pH. Some of the extract samples at various times were freezed, thawed, dried and weighed. The evaluation of experimental data showed that the mass transfer coefficient kca decreased and the gel strength of agar increased with the increase of alkali concentration. Meanwhile, the value of kca increased and the gel strength of agar decreased with the increase of acetic acid concentration.
Key words: Alkali, Acetic Acid, Soaking, Extraction, Volumetric Mass Transfer Coefficient (kca), Gel strength
oai:jurnal.ugm.ac.id:article/550
2017-03-01T05:51:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/550
2017-03-01T05:51:18Z
Jurnal Rekayasa Proses
Vol 2, No 1 (2008); 16-23
Konstanta Laju Pengeringan Daun Sambiloto Menggunakan Pengering Tekanan Rendah
Rahayoe, Sri
Rahardjo, Budi
Kusumandari, Siti
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/550
Pada penelitian ini dilakukan pengeringan bahan herbal dan obat-obatan tradisional yang peka terhadap panas yaitu daun sambiloto menggunakan pengering bertekanan rendah. Tekanan yang rendah akan membuat titik uap air akan turun sehingga air akan menguap pada suhu di bawah 100°C. Suhu rendah ini juga bertujuan untuk mengurangi tingkat kerusakan kandungan kimia bahan peka panas. Sedangkan tujuan penelitian adalah menganalisis konstanta laju pengeringan daun sambiloto selama proses pengeringan menggunakan pengering tekanan rendah. Pengeringan daun sambiloto dilakukan pada suhu dan tekanan yang bervariasi yaitu variasi suhu 30°C, 40°C, 50°C dan variasi tekanan 61 kPa, 48 kPa dan 35 kPa. Pengeringan daun sambiloto dilakukan dari kadar air ± 70% hingga ± 10%. Selama proses pengeringan perubahan kadar air diukur dengan interval waktu 10, 20, 30, 60, 90, 120, 150 dan 210 menit. Pengukuran kadar air dilakukan dengan cara termogravimetri. Analisis konstanta laju pengeringan menggunakan persamaan lapis tipis. Hasil penelitian menunjukkan nilai konstanta laju pengeringan pada tekanan rendah berkisar 0,01-0,0175 men1. Pengeringan menggunakan tekanan rendah dapat meningkatkan laju pengeringan. Persamaan empiris konstanta laju pengeringan sebagai fungsi suhu dan tekanan yang dinyatakan sebagai kprediksi = 0,00075T0,823P-0,021 dapat diaplikasikan untuk memprediksi perubahan kadar air daun sambiloto selama pengeringan pada tekanan rendah.
Kata kunci: konstanta laju pengeringan, pengeringan bertekanan rendah, daun Sambiloto
Herbs (traditional medicine) such as sambiloto leaves are senisitive to heat, therefore the drying process of herbs were performed at low-pressure. At low pressure, evaporation of water in the herbs can be carried out at a temperature below 100°C. The low temperature of drying may reduce the destruction of heat-sensitive chemicals inside the herbs. The present study aimed at analyzing the drying-rate constant of sambiloto leaves during low-pressure drying. Sambiloto leaves were dried at varied temperature of 30°C, 40°C, and 50°C, and varied pressure of 61 kPa, 48 kPa, and 35 kPa. The water content of sambiloto leaves was reduced from ± 70% to ± 10%. The change in water content was measured after 10, 20, 30, 60, 90, 120, 150 and 210 minutes, by using thermogravimetry technique. The drying-rate constant was calculated using the equation of thin films. The drying-rate constant was 0.01 – 0.0175 min-1. It was observed that the drying-rate increases as the pressure decreases. To predict the change of water content in sambiloto leaves during low-pressure drying process, an empirical equation for the drying-rate constant as a function of temperature and pressure was derived from the experimental data, kprediction= 0,00075T0,823P-0,021.
Key words: drying-rate constant, low-pressure drying, sambiloto leaves
oai:jurnal.ugm.ac.id:article/551
2017-03-01T05:51:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/551
2017-03-01T05:51:18Z
Jurnal Rekayasa Proses
Vol 2, No 1 (2008); 24-27
Studi Kinerja Katalisator Lewatit Monoplus s-100 pada Reaksi Esterifikasi antara Etanol dan Asam Asetat
Nuryoto,
2008-05-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/551
Seringkali etil asetat dibuat dengan menggunakan katalisator asam sulfat.Walaupun konversi yang dihasilkan tinggi, penggunaan katalisator asam sulfat banyak menimbulkan masalah. Proses esterifikasi antara etanol dan asam asetat dengan katalisator padat berupa resin penukar ion lewatit monoplus s-100 diharapkan dapat memecahkan permasalahan tersebut. Proses pembuatan etil asetat dilakukan dengan cara batch, perbandingan pereaksi 1,2 gmol asam asetat /gmol etanol, waktu reaksi 60 menit, dengan pengadukan berbasis bed expansion 4% mengunakan magnetit stirrer, dan katalisator lewatit monoplus s-100. Variabel yang divariasikan adalah suhu reaksi dan konsentrasi katalisator. Etanol, asam asetat, dan katalisator dimasukkan ke dalam reaktor, kemudian ambil contoh untuk dianalisis etanol awal. Tutup reaktor dengan penutup lalu hotplate dinyalakan sambil pengadukan dijalankan. Setelah 60 menit ambil sampel untuk dianalisis konsentrasi etanol. Analisis dilakukan satu kali pada akhir reaksi yaitu 60 menit dengan mengunakan kromatografi gas. Hasil percobaan menunjukkan semakin besar suhu laju reaksi semakin meningkat, tetapi naiknya konsentrasi katalisator akan menyebabkan reaksi balik. Konversi tertinggi diperoleh pada 358K, dan konsentrasi katalisator 0,8 massa resin/massa etanol, dengan konversi sebesar 87,3%. Ini menunjukkan bahwa kinerja katalisator lewatit monopluss-100 cukup baik digunakan untuk proses esterifikasi antara etanol dan asam asetat.
Kata kunci : asam asetat, esterifikasi, etanol, lewatit monoplus s-100
Sulfuric acid is common catalyst in producing ethyl acetate. Despite of high conversion, using sulfuric acid as catalyst is appearing a lot of problems. The use of solid catalyst is expected to solve the problem. Utilizing of lewatit monoplus s-100 in the esterification of ethanol and acetic acid was investigated in this work. The experiments were carried out in a reactor on the hot plate equipped with magnetic stirrer. The reactant ratio was 1.2 gmol acetic acid / gmol ethanol and lewatit monoplus s-100 as catalyst. Samples were taken at initial and after 60 minutes, then the samples were analyzed by using gas chromatograph. The same experiments were conducted at different temperatures and catalyst concentrations. Based on the experimental result, lewatit monoplus s-100 performed well as solid catalyst in the esterification. It was shown that the higher the temperature, the higher the reaction rate, meanwhile increasing the catalyst concentration, the conversion was lower. The highest conversion was 87.3%, when the temperature was 358 K, and a catalyst concentration was 0.8 g. resin /g. ethanol.
Key words: acetic acid, esterification, ethanol, lewatit monoplus s-100
oai:jurnal.ugm.ac.id:article/552
2017-03-01T05:51:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/552
2017-03-01T05:51:18Z
Jurnal Rekayasa Proses
Vol 2, No 1 (2008); 28-32
Pemanfaatan Zeolit Alam Klinoptilolite Sebagai Katalisator dalam Alkoholisis Minyak Jarak
Harjanti, Ratna Sri
2012-05-01 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/552
Penggunaan katalisator padat pada proses alkoholisis diharapkan dapat meningkatkan kemurnian ester karena katalis padat lebih mudah dipisahkan dari pada katalis cair. Salah satu jenis katalisator padat adalah zeolit alam klinoptilolite. Dengan pertimbangan kemudahan dalam pemisahan sisa katalis dari ester yang terbentuk, maka di lakukan penelitian tentang alkoholisis minyak jarak dengan katalisator zeolit klinoptilolite dalam autoklaf. Minyak jarak, etanol, dan serbuk zeolit klinoptilolite dimasukkan ke dalam autoklaf yang dilengkapi dengan manometer, termometer, kran pengambil cuplikan, dan pemanas, kemudian autoklaf diputar. Cuplikan diambil pada setiap selang waktu 10 menit. Konversi reaksi dicari dengan menganalisa kadar gliserol lapisan bawah dengan cara asetin. Reaksi dilakukan pada suhu 120°C dan pada kecepatan putaran autoklaf 110 rpm dengan variasi prosentase katalisator dan perbandingan ekivalen etanol-minyak. Pembentukan ester diawali dengan pengaktifan etanol oleh zeolit membentuk senyawa alkoxide. Alkoxide inilah yang akan menyerang gugus karbonil pada trigiserid minyak jarak, sehingga terbentuk ester. Zeolit klinoptilolite dapat digunakan sebagai katalisator reaksi alkoholisis dengan kondisi proses yang relatif baik dijumpai pada prosentase katalisator 2,56% dan perbandingan ekivalen etanol-minyak 12,55 mgek/mgek. Pada keadaan ini konversi gliserid mencapai 73%.
Kata kunci: alkoholisis, klinoptilolite, minyak jarak, zeolit
The use of solid catalyst in alcoholysis can increase the purity of ester because the separation process of solid catalyst is simpler than that of liquid catalyst. Prior to the ester formation, the ethanol was activated by the zeolite, forming alkoxide molecules. These molecules can attack the carbonyl functional group at the triglyceride in Jatropha oil and form ester. Jatropha oil, ethanol, and clinoptilolite zeolite powder were added into an autoclave equipped with manometer, thermometer, sampling valve, and heater. The autoclave was then powered up and rotated, and sampling was performed at time interval of 10 minutes. The reaction was performed at a temperature of 120°C and an autoclave rotation speed 110 rpm, with varied catalyst percentage and ethanol-oil equivalent ratio. The conversion was determined by analyzing the glycerol concentration of the lower layer with acetyl method. This study confirms that clinoptilolite type zeolite is effective catalyst for alcoholysis of jatropha oil. When the ethanol-oil ratio was 12.55 mgek/mgek, the catalyst percentage was 2.56% weight, the glyceride conversion reached 73%.
Key words: alcoholysis, clinoptilolite, Jatropha oil, zeolite
oai:jurnal.ugm.ac.id:article/553
2012-05-01T02:47:02Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/553
2012-05-01T02:47:02Z
Jurnal Rekayasa Proses
Vol 2, No 2 (2008); 33-36
Upaya Peningkatan Efisiensi Energi di Pupuk Kujang
Maryono,
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/553
ACES21 adalah teknologi proses pembuatan urea yang merupakan proses terbaru dari Toyo Engineering Corp (TEC) dengan berbagai keuntungan dibandingkan dengan teknologi sebelumnya. ACES21 dirancang dengan biaya investasi dan penggunaan energi konsumsi yang rendah. Dibandingkan dengan proses sebelumnya beberapa penyempurnaan dilakukan antara lain reaktor urea yang pada proses sebelumnya dipasang pada ketinggian 20–22 meter di atas tanah, pada ACES21 reaktor urea dipasang pada ground level sehingga dapat menurunkan biaya konstruksi. Selain itu, kondisi proses di unit sintesa dimana pada unit ini terjadi reaksi pembentukan urea dioperasikan pada tekanan yang relatif lebih rendah dari sebelumnya. Akibat penurunan tekanan ini, terjadi penurunan konsumsi energi pabrik urea secara total. Selain itu untuk kemudahan dan kehandalan operasi, pabrik urea dilengkapi beberapa peralatan pengamatan langsung yang belum banyak diaplikasikan di dunia seperti N/C monitoring, leak detector monitoring, dan analyzer monitoring (ACES21, On-line Monitoring, Ground Level). Dengan beroperasinya Pupuk Kujang IB yang menggunakan proses ACES21, konsumsi energi yang semula 8,324 Gcal/ton urea menjadi 5,623 Gcal/ton urea, sehingga terjadi penghematan yang sangat signifikan dibanding proses sebelumnya.
Kata kunci: ACES21, sintesis urea, reaktor, energi
ACES21 is an urea manufacturing process technology which is the latest process of Toyo Engineering Corp. (TEC) with some advantages compared with previous technologies. ACES21 is designed with low investment cost and low energy consumption. Compared with the previous process some improvements have been done such as urea reactor that in the previous process was installed at a height of 20-22 meters above the ground, on ACES21 urea reactor was installed at ground level so that it can reduce construction costs. The synthesis process conditions where the urea formation reaction occurs is operated at relatively lower pressure than before that eventually reduces energy consumption. In addition to the ease and reliability of the operation, the urea plant has several on-line monitoring equipment that has not been widely applied such as nitrogen/carbon ratio monitoring, leak detector monitoring, and analyzer monitoring (ACES21, On-line Monitoring, ground Level). With the operation of Kujang IB that already uses ACES21 process, the energy consumption which in the previous process (Kujang 1A) was originally 8.324 Gcal/tonne of urea is reduced to 5.623 Gcal/tonne of urea, resulting in a significant energy saving.
Key words: ACES21, urea synthesis, reactor, energy.
oai:jurnal.ugm.ac.id:article/554
2012-05-01T02:47:03Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/554
2012-05-01T02:47:03Z
Jurnal Rekayasa Proses
Vol 2, No 2 (2008); 37-40
Sifat-Sifat Penyalaan dan Pembakaran Briket Biomassa, Briket Batubara dan Arang Kayu
Jamilatun, Siti
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/554
Secara umum, proses pembakaran padatan terdiri atas beberapa tahap yaitu pemanasan, pengeringan, devolatilisasi dan pembakaran arang. Faktor-faktor yang menentukan karakteristik pembakaran suatu briket adalah kecepatan pembakaran, nilai kalor, berat jenis dan banyaknya polusi atau senyawa volatil yang dihasilkan. Penelitian ini bertujuan untuk mengetahui sifat-sifat penyalaan dari berbagai macam briket biomassa, arang kayu dan batubara yang meliputi kecepatan pembakaran, lama briket menyala sampai menjadi abu, waktu penyalaan awal, banyaknya asap atau senyawa volatil yang dihasilkan, nilai kalor dan lama waktu untuk mendidihkan 1 liter air. Penelitian dilakukan dengan membakar 250 gram setiap jenis briket. Hasil penelitian menunjukkan bahwa tempurung kelapa memiliki lama menyala terpanjang yaitu 116 menit dengan kecepatan pembakaran 126,6 gram/detik dan nilai kalor tertinggi sebesar 5.779,11 kal/gram. Untuk mendidihkan 1 liter air, semua jenis briket yang diuji membutuhkan waktu antara 5 sampai 7 menit. Jika dibandingkan dengan briket batubara yang memiliki nilai kalor 6.058 kal/gram dan arang kayu dengan nilai kalor 3.583 kal/gram maka briket tempurung kelapa cukup baik digunakan sebagai bahan bakar alternatif.
Kata kunci: briket, biomassa, batubara, uji pembakaran dan nilai kalor
In general, combustion of solid material consists of several steps including heating, drying, de-volatilization and burning of the charcoal. The factors that determine combustion characteristics of briquettes are the rate of combustion, heating value, density and amount of pollutants or volatile compounds produced. The present work aimed at determining combustion characteristics of various kinds of briquettes from biomass, wood charcoal and coal including the rate of combustion, duration of briquettes burn to ashes, the initial ignition, amount of smoke or volatile compounds produced, heating value and duration for boiling one liter of water. The experimental work was performed by burning 250 grams of each briquette. The results showed that coconut shell had the longest combustion duration (116 minutes) with a combustion rate of 126.6 grams/second. In comparison with other biomass briquettes and wood choarcoal, coconut shell had the highest heating values of 5,779.11 cal/gram which was close to heating value of coal briquette (6,058 cal/gram). All briquettes studied in the present work showed a reasonable duration and needed about 5 – 7 minutes to boil one litter of water.
Key words: briquette, biomass, coal, combustion test and heating values
oai:jurnal.ugm.ac.id:article/555
2012-05-01T02:47:03Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/555
2012-05-01T02:47:03Z
Jurnal Rekayasa Proses
Vol 2, No 2 (2008); 41-44
Pemodelan Matematis Reaksi Oksidasi Katalitik Fero Sulfat Menjadi Feri Sulfat
Syarif, Takdir
Yuwono, Andiyan
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/555
Larutan fero sulfat (FeSO4) dibuat dengan melarutkan besi ke dalam asam sulfat. Fero sulfat dioksidasi memakai katalisator mangaan dioksid untuk membentuk feri sulfat. Reaksi merupakan reaksi heterogen tiga fasa sehingga kinetika reaksinya cukup komplek. Penelitian ini bertujuan mengembangkan model matematis pada kinetika reaksi tiga fase. Reaksi djalankan pada kondisi isotermal dan isobarik pada rekator yang berupa labu leher tiga. Percobaan dilakukan pada suhu 323K sampai 353K dan konsentrasi katalisator 1,7 g/L. Hasil penelitian menunjukan bahwa kinetika reaksi dapat didekati dengan model quasi steady state dan rekasi kimia pada permukaan katalisator merupakan langkah yang menentukan kinetika reaksi.
Kata kunci: pemodelan matematis, kinetika, langkah penentu
Iron was dissolved in a sulfuric acid to form a concentrated ferrous sulphate (FeSO4) solution. This research was conducted to form ferric sulfate by catalytic oxidation of ferrous sulfate using manganese dioxide as catalyst. The system was a three-phase heterogeneous reaction with a quite complex kinetics The present study aimed at developing a mathematical modeling of three-phase reaction kinetics that involved gas, liquid and solid. Oxidation was undertaken in an isothermal isobaric condition in a three-neck flask reactor. The experiment was conducted in a temperature range of 323 to 353 K with a catalyst concentration of 1.7 g/L. The results indicated that the reaction kinetics could be approached with a quasi steady state model and the chemical reaction on the catalyst surface was the determining step.
Key words: mathematical modeling, kinetics, determining step
oai:jurnal.ugm.ac.id:article/556
2012-05-01T02:47:03Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/556
2012-05-01T02:47:03Z
Jurnal Rekayasa Proses
Vol 2, No 2 (2008); 45-48
Hidrolisis Minyak Biji Kapuk dengan Katalisator Asam Khlorida
Andaka, Ganjar
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/556
Reaksi hidrolisis minyak biji kapuk memakai asam khlorida sebagai katalisator untuk membentuk gliserol dan asam lemak dilakukan dengan mempelajari pengaruh suhu reaksi dan konsentrasi katalisator terhadap konstanta kecepatan reaksi. Percobaan dilakukan dalam reaktor yang berupa labu leher tiga yang dilengkapi dengan pendingin, pemanas, pengaduk dan termometer sebagai pengukur suhu. Percobaan dilakukan pada kisaran suhu 80 sampai 100oC, konsentrasi katalisator 0,011 sampai 0,017 N dan waktu reaksi 3 jam. Konsentrasi trigliserida setiap 0,25 jam dianalisis untuk menghitung konversi trigliserid. Hasil penelitian menunjukkan bahwa kinetika reaksi hidrolisis minyak biji kapuk mengikuti reaksi tingkat satu terhadap konsentrasi trigliserida. Pengaruh suhu terhadap konstanta kecepatan reaksi dapat disajikan dalam persamaan k = 0,3258 exp(−1379,8875/RT) jam−1 dengan nilai tenaga pengaktif 1379,8875 cal/mol. Hubungan konsentrasi katalisator dengan konstanta kecepatan reaksi dituliskan dalam persamaan k = 0,06002 exp(−0,0025/Ck) jam−1.
Kata kunci: kinetika, hidrolisis, minyak biji kapuk, asam lemak, gliserol
Hydrolysis of kapok seed oil in the presence of hydrochloric acid catalyst to produce glycerol and fatty acid was studied. The objective of this work was to study the effect of reaction temperature and catalyst concentration on the reaction rate constant. The experiments were conducted in a three-neck flask equiped with stirrer, heater, condenser, and thermometer. The reaction condition studied were temperature ranging from 80 to 100C and catalyst concentration from 0.011 to 0.017 N. The reaction time was kept constant at 3 hours. The concentration of triglycerides every 0.25 hour were analyzed to calculate the conversion of triglycerides. The results of this study showed that the reaction kinetics of the hydrolysis of kapok seed oil was found to be first order with respect to triglyceride. The effect of reaction temperatures on the reaction rate constant was found to be k = 0.3258 exp(−1379.8875/RT) h−1, the activation energy was 1379.8875 cal/mol and the effect of catalyst concentrations on the reaction rate constant could be expressed as k = 0.06002 exp(−0.0025/Ck) h−1.
Key words: kinetics, hydrolysis, kapok seed oil, fatty acid, glycerol
oai:jurnal.ugm.ac.id:article/557
2012-05-01T02:47:03Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/557
2012-05-01T02:47:03Z
Jurnal Rekayasa Proses
Vol 2, No 2 (2008); 49-54
Pemungutan Kurkumin dari Kunyit (Curcuma domestica val.) dan Pemakaiannya Sebagai Indikator Analisis Volumetri
Harjanti, Ratna Sri
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/557
Analisa volumetri merupakan salah satu metode analisa kwantitatif, yang sangat penting penggunaannya dalam menentukan konsentrasi zat yang ada dalam larutan. Keberhasilan analisa volumetri ini sangat ditentukan oleh adanya indikator yang tepat sehingga mampu menunjukkan titik akhir titrasi yang tepat. Kurkumin, zat warna yang terkandung dalam umbi tanaman kunyit (Curcuma domestica val.) ternyata mampu berfungsi sebagai indikator karena terjadinya perubahan warna dari kuning muda coklat menjadi coklat pada pH sekitar 4,5 – 9,9. Untuk mengambil kurkumin dari umbinya, dilakukan dengan cara ekstraksi. Hasil ekstraksi disebut oleoresin. Dalam hal ekstraksi oleoresin, peranan pelarut, lama ekstraksi, suhu ekstraksi, dan kehalusan partikel sangat penting. Pada pengambilan zat warna kurkumin, kunyit yang sudah dihaluskan dikenakan proses ekstraksi dengan variasi suhu operasi, lama ekstraksi, dan kehalusan serbuk kunyit. Solven yang digunakan adalah etanol. Hasil ekstraksi kemudian didistilasi dan ditimbang . Kurkumin yang diperoleh pada kondisi optimum diuji kadarnya menggunakan TLC Scanner. Pemanfaatan kurkumin sebagai indikator dalam analisa volumetri dilakukan dengan cara titrasi menggunakan beberapa sampel asam basa dan membandingkannya dengan titrasi menggunakan indikator pp dan mo. Hasil penelitian menunjukkan bahwa kondisi optimum pengambilan kurkumin adalah pada suhu 70°C, ukuran partikel kunyit 100 mesh selama 120 menit menggunakan pelarut alcohol. Kurkumin yang dihasilkan memiliki kadar 5,158 mg/mL. Kurkumin yang akan digunakan sebagai indikator titik akhir pada analisa volumetri harus diencerkan terlebih dahulu menjadi 5% volume sebanyak 4 tetes.
Kata kunci: indikator, kurkumin, titrasi, ekstraksi
Volumetric analysis is one of quantitative analysis methods; a very important method used in determining the concentration of substances in solution. The success of this analysis was determined by the existence of an appropriate indicator that can show the exact end-point of titration. Curcumin, a natural dye contained in the plant root of turmeric (Curcuma domestica val.) was able to function as an indicator for the color change from light yellow brown to brown at pH around 4.5 to 9.9. Curcumin is extracted from the tuber which result is called oleoresin extraction. In the case of extraction of oleoresin, the role of solvent, extraction duration, temperature, and the fineness of particles is very important. In the present work curcumin pigment was extracted from turmeric paste in ethanol as solvent at varying operating conditions; i.e temperature, duration of extraction, and particle size of turmeric powder. The extract was further distilled and weighed. The curcumin obtained at optimum conditions was then determined using a TLC Scanner. The use of curcumin as an indicator in volumetric analysis was done by mean of titration using a few acid-basic samples. The results were compared with results from titrations using phenolphthalein (pp) and methyl-orange (mo) as indicators. The results showed that the optimum condition of curcumin extraction were at a temperature of 70°C for 120 minutes with a turmeric particle size of 100 mesh. The curcumin produced had a relatively high concentration of 5.158 mg/mL. In order to use it as an indicator for the end-point of volumetric analysis, the curcumin should be diluted to obtain 5% solution and use as much as 4 drops of the solution for the titration.
Key words: indicator, curcumin, titration, extraction
oai:jurnal.ugm.ac.id:article/558
2012-05-01T03:23:40Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/558
2012-05-01T03:23:40Z
Jurnal Rekayasa Proses
Vol 3, No 1 (2009); 1-4
Biosorpsi Pb (II) Pada Jamur Trichoderma Asperrellum TNJ-63
Heltina, Desi
Evelyn,
Indriani, Renny
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/558
Logam berat Pb2+ merupakan senyawa yang sangat beracun dan sangat berbahaya bagi makhluk hidup. Salah satu cara untuk menanggulanginya adalah dengan biosorpsi menggunakan jamur. Penelitian ini bertujuan menentukan kapasitas jerap maksimum dan model kesetimbangan biosorpsi Pb2+dengan menggunakan jamur Trichoderma asperellum TNJ-63. Sejumlah jamur Trichoderma asperellum TNJ-63 dimasukkan ke dalam erlenmeyer yang berisi larutan Pb2+ 100 ppm pada suhu ruang dengan massa jamur yang divariasikan. Lama waktu tercapainya kesetimbangan dipelajari dengan memvariasi lama waktu penjerapan dan kecepatan pengadukan. Hasil penelitian menunjukkan bahwa maksimum penjerapan Pb2+ pada jamur Trichoderma asperellum TNJ-63 adalah sebesar 98,24%. Mekanisme proses biosorpsi Pb2+ pada Trichoderma asperellum TNJ-63 mengikuti model isoterm Freundlich.
Kata kunci: logam berat, biosorpsi, jamur Trichoderma asperellum, isoterm Freundlich
Heavy metal Pb2+ is a highly toxic substance and is very dangerous for living creatures. Biosorption with fungi is one of the abatement methods to reduce the metal contaminant in environment. The present study aimed at determining the maximum biosorption capacity and the equilibrium model of Pb2+ biosorption by Trichoderma asperellum TNJ-63. Some Trichoderma asperellum TNJ-63 varied in amount were put into an erlenmeyer flask containing a solution of Pb2+ with an initial concentration of 100 ppm at room temperature. Variation of stirring speeds (80, 130 and 180 rpm) was also carried out to study its effect on the time required to reach equilibrium. The result showed that Pb2+ could be effectively adsorbed by Trichoderma asperellum TNJ-63 as the biosorbent and its biosorption could reach its maximum by as much as 98.24% (w/w). Calculation result showed that the mechanism of Pb2+ biosorption on Trichoderma asperellum TNJ-63 followed Freundlich isotherm model with an average error of 0.098%.
Keywords: heavy metal, biosorption, Trichoderma asperellum, Freundlich isotherm
oai:jurnal.ugm.ac.id:article/559
2012-05-01T03:23:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/559
2012-05-01T03:23:41Z
Jurnal Rekayasa Proses
Vol 3, No 1 (2009); 5-9
Pengaruh Penambahan Nutrisi Terhadap Efektifitas Fitoremediasi Menggunakan Tanaman Enceng Gondok (Eichhornia crassipes) Terhadap Limbah Orto-Klorofenol
Purwaningsih, Is Sulistyati
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/559
Limbah pabrik pulp dan kertas mengandung senyawa-senyawa fenol dan klorofenol yang sangat berbahaya jika dibiarkan berada di perairan. Senyawa-senyawa tersebut sangat beracun dan sulit untuk didegradasi. Fitoremediasi terbukti merupakan metode yang efektif dan ekonomis untuk mereduksi konsentrasi polutan di sistem perairan. Pada penelitian ini tanaman enceng gondok dipilih untuk meremediasi air yang terkontaminasi o-klorofenol. Penelitian dilakukan dengan menggunakan 2 reaktor batch yang diberi perlakuan berbeda, yaitu tanpa dan dengan penambahan nutrisi dengan variasi konsentrasi kontaminan 0 hingga 20 mg/L. Remediasi o-klorofenol oleh enceng gondok dipengaruhi oleh besarnya konsentrasi awal o-klorofenol. Semakin besar konsentrasi awal o-klorofenol maka laju remediasi semakin besar. Dari penelitian diperoleh remediasi o-klorofenol terbesar terjadi pada konsentrasi awal 20 mg/L, laju remediasinya 4,59 kali lebih cepat daripada konsentrasi awal 5 mg/L. Laju remediasi o-klorofenol dengan penambahan nutrisi lebih cepat daripada tanpa penambahan nutrisi. Dari penelitian diperoleh remediasi o-klorofenol dengan penambahan nutrisi lebih cepat 1,23–1,33 kali daripada fitoremediasi tanpa penambahan nutrisi. Selain itu, pada fitoremediasi selama 48 jam setiap 500 gram enceng gondok mampu menjerap o-klorofenol sebanyak 41-59% dari konsentrasi awalnya.
Kata kunci: enceng gondok, fitoremediasi, o-klorofenol, nutrisi.
Pulp and paper wastewater contains a vast variety of chemicals including phenolic and chlorinated phenolic compounds. The toxicity of these two phenolic compounds in water has led to environmental problem due to resistance or complete recalcitrance to metabolic breakdown by the majority of living species. Phytoremediation is one of the most effective and economic way of reducing the toxic compounds in wastewater system. In this research enceng gondok (Eichhornia crassipes) was choosen as ortho-chorophenol phytoremediation agent.
Experiment was conducted in 2 batch reactor systems; one reactor without nutrient addition and the other one with 1.06 mg/L of NPK addition as nutrition. Both systems were carried out over range of pollutan concentration of 0 -20 mg/L.
Experimental result showed that the remediation of o-chlorophenol using enceng gondok was influenced by the initial concentration of pollutan. The rate of o-chlorophenol uptake increased when o-chlorophenol concentration higher. It was shown that the highest o-chlorophenol uptake rate reached at 20 mg/L of initial concentration, in which its uptake rate was 4.59 times faster compared to uptake rate at 5 mg/L of o-chlorophenol concentration . With nutrient addition, the rate of o-chlorophenol uptake was 1.23 – 1.33 times faster than the process without nutrient addition. Experimental result also indicated that after 48 hours remediation , every five hundreds (500) gram of enceng gondok was able to adsorp more than 50 % of o-chlorophenol from its initial concentration.
Keywords: Eichhornia crassipes, o-chlorophenol, phytoremediation, nutrion
oai:jurnal.ugm.ac.id:article/560
2012-06-14T07:45:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/560
2012-06-14T07:45:41Z
Jurnal Rekayasa Proses
Vol 3, No 1 (2009); 10-14
Pemutihan Daun Nanas Menggunakan Hidrogen Peroksida
Jayanudin, Jayanudin
2012-05-01 20:08:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/560
Daun nanas mengandung selulosa sekitar 69,5% - 71,5%, sehingga dapat dijadikan bahan baku alternatif pembuatan kertas. Kualitas kertas dapat ditingkatkan dengan melakukan proses pemutihan mengunakan H2O2 karena senyawa ini lebih ramah lingkungan. Tujuan penelitian ini adalah untuk mengetahui kondisi optimum yaitu waktu dan suhu pemutihan. Tahapan penelitian ini adalah daun nanas kering dihidrolisis memakai larutan NaOH dengan konsentrasi 0,1, 0,2, 0,3 dan 0,35 N sebanyak 400 mL dalam labu leher tiga yang dilengkapi dengan pendingin balik pada suhu 100°C. Proses pemutihan menggunakan H2O2 konsentrasi 2% pada suhu 40°C, 60°C dan 80°C selama 1, 1,5 dan 2 jam. Pulp hasil pemutihan dianalisis menggunakan Colorgard System 2000 Colorimeter Byk Garder dengan parameter L*, a* dan b*. Kondisi optimum proses pemutihan pada suhu 60°C dan waktu perendaman selama 1,5 jam. Parameter yang didapat yaitu L* = 95,14%; a* = -2,15 dan b* = 5,42 yang memenuhi syarat derajad putih industri.Kata kunci: daun nanas, hidrolisis, hydrogen peroksida, pemutihan, selulosa A pineapple leaf contains approximately 69.5% - 71.5% cellulose, which makes it a good alternative raw material in paper production. The quality of paper produced can be enhanced by bleaching process with the use of hydrogen peroxide (H2O2) as an environmentally friendly bleaching agent. The purpose of this study was to determine the optimum temperature and duration of the soaking or bleaching process of pineapple leaves. Dried pineapple leaves were hydrolyzed in a solution of NaOH with a varying concentration of 0.1, 0.2, 0.3 and 0.35 N at 100°C in a 400 ml three-neck flask equipped with a cooler. The bleaching process was conducted in the presence of 2% H2O2 at 40C, 60C and 80C for a varying time duration of 1, 1.5 and 2 hours. The resulting pulp was analyzed by the Colorgard System 2000 Colorimeter Byk Garder using parameters L*, a* and b*. The optimum bleaching process was achieved at 60C with a soaking time of 1.5 hours where the values of parameter L*, a* and b* were 95.14%, -2.15 and 5.42, respectively. Keywords: pineapple leaf, hydrolysis, hydrogen peroxide, bleaching, cellulose
oai:jurnal.ugm.ac.id:article/561
2012-05-01T03:23:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/561
2012-05-01T03:23:41Z
Jurnal Rekayasa Proses
Vol 3, No 1 (2009); 15-21
Kinetika Reaksi Heterogen Etanolisis Minyak Jarak Kepyar (Ricinus communis) dengan Katalisator Zeolit Klinoptilolit
Harjanti, Ratna Sri
Sarto,
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/561
Minyak jarak kepyar mempunyai potensi untuk dijadikan biodiesel melalui proses alkoholisis katalitik. Zeolit alam klinoptilolit berpotensi digunakan sebagai katalisator dalam alkoholisis tersebut. Pada penelitian ini, alkoholisis minyak jarak dilakukan pada suhu tinggi dengan katalisator zeolit alam klinoptilolit dalam sebuah reaktor autoklaf yang dilengkapi dengan manometer, termometer, kran pengambil cuplikan, dan pemanas. Data percobaan menunjukkan bahwa pada kisaran waktu tertentu, peningkatan suhu dan putaran autoklaf mengakibatkan peningkatan konversi gliserid. Hasil analisis kinetika reaksi menunjukkan bahwa reaksi kimia pada permukaan katalisator merupakan langkah yang mengendalikan kecepatan reaksi keseluruhan. Kondisi proses yang relatif optimum terjadi pada waktu 60 menit, suhu 120°C dan kecepatan putaran autoklaf 110 rpm dengan perbandingan alkohol-minyak 12,56 mgek/mgek dan prosentase katalisator 2,56 %. Pada keadaan ini konversi gliserid mencapai 0,73 bagian. Ester dari minyak jarak yang diperoleh memiliki viskositas 8,0 cst, titik tuang -16,6°F, titik nyala 215°F, warna ASTM 1, dan nilai kalor 19.119 Btu/lb.
Kata kunci: alkoholisis, klinoptilolit, minyak jarak, zeolit
Castor oil of Ricinus communis has potential as a raw material for biodiesel synthesis through catalytic alcoholysis process. Clinoptilolite type natural zeolite is one of solid catalysts that can be used in the alcoholysis process. In the present work, the alcoholysis was carried out in an autoclave reactor equipped with manometer, thermometer, sampling valve, and heating element. The reaction occurred at elevated temperatures with the use of clinoptilolite as a solid catalyst. The experimental data indicated that in a certain reaction time range, an increase in temperature and autoclave rotation speed lead to the increase of reaction conversion. Calculation results showed that the overall reaction rate was controlled by chemical reaction at the catalyst surface. The optimum condition of the alcoholysis process was obtained at reaction time of 60 minutes, temperature of 120C and autoclave rotation of 110 rpm with the use of alcohol-oil ratio of 12.56 mgek / mgek and 2.56% (w/w) catalyst. At the optimum condition, the conversion could reach as high as 0.73. The obtaining esters had a viscosity of 8.0 cst, -16.6°F pour point, 215°F flash point, ASTM color of 1, and heating value of 19,119 Btu/lb.
Keywords: alcoholysis, clinoptilolite, castor oil, zeolite
oai:jurnal.ugm.ac.id:article/562
2012-05-01T03:23:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/562
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Jurnal Rekayasa Proses
Vol 3, No 1 (2009); 22-25
Optimasi Struktur Proses dan Penerapan Metodologi Six Sigma di Unit NPK Phonska – PT Petrokimia Gresik
Setyanto, Arief
Purwanto, F
Anurogo, Dwi Satrio
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/562
PT Petrokimia Gresik mempunyai tujuh Unit Pabrik Pupuk NPK dengan total kapasitas produksi saat ini adalah dua juta ton per tahun. Kapasitas terpasang tersebut jauh lebih tinggi dibanding kapasitas desain awalnya. Upaya peningkatan kapasitas produksi dilakukan secara simultan dengan optimasi proses, modifikasi peralatan serta perbaikan metode kerja. Salah satu unit pabrik yang digunakan sebagai studi kasus adalah Unit Pabrik NPK Phonska II yang telah berhasil meningkatkan kapasitas produksi dari 1.320 ton per hari menjadi 2.400 ton per hari, atau 182% dari kapasitas desain awalnya. Optimasi proses menghasilkan penyederhanaan jalur reaksi sehingga didapatkan pengurangan struktur proses. Modifikasi peralatan dilakukan menyesuaikan dengan proses terbaru, sedangkan perbaikan metode kerja dilakukan dengan penerapan metodologi six sigma. Keseluruhan tahapan dilakukan oleh engineer dan teknisi PT Petrokimia Gresik, sehingga pencapaian yang didapatkan merupakan kebanggaan bersama. Peningkatan kapasitas produksi pupuk yang signifikan itu juga memberi sumbangan berarti bagi upaya negara dalam mencapai dan mempertahankan swasembada pangan.
Kata kunci: phonska, struktur proses, jalur reaksi, optimasi, modifikasi, six sigma
PT Petrokimia Gresik has seven NPK fertilizer plants with total production capacity of two million tons per year. The existing capacity is much higher in comparison with its design capacity. An effort to increase the production capacity was done simultaneously by process optimization, equipment modifications and operational method improvement. The present work was a case study from NPK Phonska Plant II; one of the plants that has already successfully increased its capacity from 1,320 tons / day to 2,400 tons / day or 182% of its original design capacity. The process optimization resulted in reduction of reaction path and process structure. Equipment modifications were done according to the new process, meanwhile improvement ofthe operational method was done through six sigma's methodology implementation. All improvement steps were done by local engineers and technicians of PT Petrokimia Gresik andthe achievement therefore becamea pride of all constituents involved in the project. The significant improvement in fertilizer production capacity also gave large contribution to the national effort in achieving and keeping self-sufficient foodstoke.
Keywords: Phonska, process structure, reaction path, optimization, modification, six-sigma
oai:jurnal.ugm.ac.id:article/563
2012-05-01T03:49:40Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/563
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Jurnal Rekayasa Proses
Vol 3, No 2 (2009); 26-29
Bahan Bakar Padat dari Biomassa Bambu dengan Proses Torefaksi dan Densifikasi
Azhar,
Rustamaji, Heri
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/563
Bambu sebagai biomassa dapat dijadikan sebagai bahan bakar padat dengan metode torefaksi dan dengan proses pemadatan (densification). Bambu dipotong-potong kemudian dilakukan proses torefaksi di dalam furnace. Bambu hasil proses torefaksi kemudian digiling atau ditumbuk hingga halus. Serbuk bambu itu kemudian diambil dan dipres sampai menghasilkan briket. Briket kemudian ditentukan nilai bakarnya (calorific value), dilakukan analisis proksimat, analisis ultimate serta laju keterbakaran. Proses torefaksi berhasil dilakukan pada suhu 200-300°C dan diperoleh produk arang yang, memiliki sifat getas, hidrofobik dan kandungan air yang menurun. Densitas briket bambu berpengaruh terhadap nilai bakarnya. Briket bambu dengan densitas lebih besar memiliki nilai bakar lebih tinggi. Laju keterbakaran briket dari bambu hasil torefaksi dipengaruhi oleh densitas. Briket dengan densitas lebih tinggi laju keterbakarannya lebih kecil. Proses torefaksi dan densifikasi dapat meningkatkan persentase kandungan karbon dan nilai bakar bambu sekitar 19-20% pada suhu 200-300°C.
Kata kunci: bahan bakar padat, biomassa, bambu, torefaksi, densifikasi
Bamboo can be utililized as biomass through torrefaction and densification processes and be used as solid fuel. In the present work, bamboo was cut into pieces followed by torrefaction process in a furnace. The product of the torrefaction process was then milled or ground to produce smooth powder which was then pressed to form briquettes. The resulting briquettes were characterized by determining their calorific value, proximate analysis, ultimate analysis and burning rate. The torrefaction process was successfully carried out in a temperature range of 200-300°C to obtain charcoal that had following properties: brittle, hydrophobic with decreasing moisture content. The experimental results showed that the calorific value was influenced by bamboo briquette density. Greater the density higher the calorific value of the resulting brequettes. In addition, the rate of burning was also determined by the density. The briquettes that had higher density had lower burning rate. The results showed that torrefaction and densification processes could increase carbon content and calorific value of the bamboo brequttes by 19-20% in a temperature range of 200 – 300°C.
Key words: solid fuels, biomass, bamboo, torrefaction, densification Abstrak
oai:jurnal.ugm.ac.id:article/564
2012-05-01T03:49:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/564
2012-05-01T03:49:41Z
Jurnal Rekayasa Proses
Vol 3, No 2 (2009); 30-36
Pemurnian Metanol dari Kandungan Tri Methyl Amine di PT. Kaltim Methanol Industri – Bontang Kaltim
Putro, Imam Karfendi
Nugroho, Andrian
Hasanudin, Nanang
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/564
PT Kaltim Methanol Industri memproduksi metanol grade AA yaitu metanol yang mempunyai kemurnian di atas 99,85 %. Pelanggan/konsumen metanol dari luar negeri menginginkan produk metanol dari PT Kaltim Methanol Industri memiliki kandungan trimethylamine (TMA) serendah mungkin (kurang dari 50 ppb). TMA dapat berada dalam bentuk TMA bebas dan dalam bentuk senyawa asam dalam larutan seperti pada crude methanol. TMA bebas mempunyai titik didih 3ºC pada tekanan 1 atm dan mudah dipisahkan dari methanol dengan distilasi sedangkan TMA pada suasana asam tidak bisa dipisahkan secara distilasi biasa. Pada umumnya cara untuk menghilangkan TMA adalah dengan menginjeksikan larutan NaOH ke kolom distilasi. Di dalam kolom distilasi, pH tinggi (basa) akan menyebabkan TMA dalam crude methanol menjadi lebih mudah menguap dan kemudian terbuang bersama dengan off-gas. Kondisi umpan gas alam dan pabrik yang dinamis menyebabkan kandungan TMA di dalam produk methanol bervariasi. Penelitian ini bertujuan untuk mencari kemungkinan penyebab kenaikan kandungan TMA dalam produk metanol baik oleh faktor alam maupun akibat perubahan kondisi operasi pada proses pemisahan sebelumnya di unit destilasi. Hasil penelitian menunjukkan bahwa kandungan CO2 dalam gas alam dapat meningkatkan kandungan TMA dalam produk metanol. Penambahan larutan NaOH ke dalam menara distilasi dapat menurunkkan kandungan TMA dalam produk akhir.
Kata kunci: trimethylamine, off gas, grade AA, methanol, distilasi
PT Kaltim Methanol Industri (KMI) produces grade AA methanol which has a purity of above 99.85%. The overseas customers or consumers of the methanol product require that the methanol should contain trimethylamine (TMA) as low as possible (less then 50 ppb). TMA might be present either in the free form TMA or in the form of acidic coumponds in a solution such as found in the crude methanol. Free TMA has a low boiling point of 3°C (1 atm) and is easily separated from the methanol by distillation. Meanwhile, TMA in the form of acidic compounds is relatively difficult to separate by ordinary distillation. Generally, to eliminate the TMA, NaOH solution is injected to the distillation column. In the distillation column, a high pH (alkaline) will cause the TMA in crude methanol becomes more volatile and therefore be possible to remove it along with the off-gas. The condition of natural gas in the feedstock and the dynamic of the process plant cause the TMA content in the resulting methanol fluctuating. This study aimed at determining the possible causes of the increase of methanol content of TMA in the product either by natural factors or due to changes in the operating conditions prior to the separation process in the distillation unit. The study showed that the increase of CO2 content in the natural gas feedstock would increase the amount of TMA in the crude methanol. Addition of NaOH solution injection to the distillation column would help to decrease the TMA content in the final methanol product.
Key words: trimethylamine, off gas, grade AA, methanol, distillation
oai:jurnal.ugm.ac.id:article/565
2012-05-01T03:49:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/565
2012-05-01T03:49:41Z
Jurnal Rekayasa Proses
Vol 3, No 2 (2009); 37-44
Numerical Method for Front Tracking in Mold Filling Modeling in Composite Injection Molding: Non-reacting System
Fahrurrozi, Mohammad
Collier, John R.
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/565
Pemodelan proses pengisian cetakan sangat penting untuk perancangan cetakan untuk pencetakan komposit polimer. Harga software komersial untuk simulasi pengisian cetakan sangat mahal untuk ukuran rata-rata perusahaan Indonesia. Keberadan software yang lebih terjangakau akan mendorong perkembangan teknologi domestik yang berhubungan dengan pencetakan komposit polimer. Paper ini menyajikan pemodelan pengisian cetakan komposit polimer dalam sistem 3 dimensi berbasis metoda numeris control volume finite difference (CV-FD) pada elemen yang tetap (fixed grids). Pemodelan bentuk ujung aliran polimer (front) dilakukan dengan menggunakan metoda volume of fluid (VOF). Profile kecepatan dihitung dengan menggunakan persamaanDarcy untuk sistem 3 dimensi. Perhitungan dilakukan dengan menggunakan bahasa pemrogaman Fortran dan penggambaran hasil perhitungan dilakukan dengan menggunakan Matlab. Model yang dikembangkan dapat mendekati hasil pengukuran secara eksperimen untuk tekanan pada lobang pemasukan (gate) dengan relatf baik. Karena data eksperimen perkembangan ujung aliran olimer tidak ada, maka hasil perhitungan model yang dikembangkan dibandingkan dengan hasil perhitungan dengan menggunakan software yang dikembangkan dan digunakan oleh US NIST. Software yang dikembangakn dapat memperkirakan dengan baik posisi ujung aliran polimer yang dihitung dengan menggunakan software dari US NIST.
Kata kunci: komposit, polimer, pencetakan, pemodelan
Mold filing simulation is important in mold design for liquid composite molding. Cost of commercial software for mold filling simulation is very expensive for average Indonesian companies. Therefore a more affordable simulation program is necessary to promote development of domestic technology related to liquid composite molding. This paper presents 3-dimension mold filling model based on control volume finite difference (CV-FD) numerical method on fixed grids. Front tracking was performed using volume of fluid method (VOF) implemented on CV-FD. Velocity field was computed using Darcy's equation. Computation was implemented on Fortran while contour plot were prepared using Matlab. The developed model predicts well gate pressure obtained experimentally. Since experimental data for front advancement is not available, calculation results were compared with results for other software developed by US’s NIST. The developed model predict front position obtain by the other software quite well.
Key words: mold filling, simulation, reaction, injection, composites
oai:jurnal.ugm.ac.id:article/566
2012-05-01T03:49:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/566
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Jurnal Rekayasa Proses
Vol 3, No 2 (2009); 45-49
Kinetika Reaksi pada Pembuatan Glifosat dari N-PMIDA (Neophosphonomethyl Iminodiacetic Acid) dan H2O2 dengan Katalisator Pd/Al2O3
Sinaga, Irmawaty
Rahayuningsih, Edia
Bendiyasa, I Made
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/566
Kebutuhan glyphosate di Indonesia meningkat sebanyak 0,75% per tahun. Saat ini, Indonesia mengimpor bahan ini dari Cina. Untuk mengurangi jumlah glyphosate impor, dibutuhkan glyphosate hasil produksi lokal. Penelitian ini bertujuan untuk mencapai kecepatan reaksi primer dalam memproduksi glyphosate dari neophosphonomethyl iminodiacetic acid (NPMIDA) dan hidrogen peroksida (H2O2), dan kecepatan reaksi sekunder AMPA pada variasi rasio reaktan dan suhu. Katalisator yang digunakan adalah palladium pada alumina (Pd/Al2O3). Lima gram NPMIDA dimasukkan ke dalam sebuah labu leher tiga 500 mL, dan 85 mL akuades ditambahkan ke dalamnya. Kemudian, 1 mL H2O2 ditambahkan ke dalam labu tersebut setiap 20 menit. Produk dari reaksi di saring dengan penyaringan vakum dan direaksikan dengan 130 mL etanol. Pemisahan glyphosate dilakukan dengan menyaring dan mencucinya dengan etanol dan dietil eter. Kemurnian produk glyphosate dianalisa menggunakan spektrometer UV/Vis.
Kata kunci: glisin, oksidasi, katalisator logam mulia
The need of glyphosate in Indonesia is increasing by about 0.75% annually. Nowadays, Indonesia imports the compound from China. In order to decrease the amount of imported glyphosate, it is necessary to produce it locally. This research aims at achieving primary reaction rate of producing glyphosate from neophosphonomethyl iminodiacetic Acid (NPMIDA) and hydrogen peroxide (H2O2), and secondary reaction rate of aminomethylphosphonic acid (AMPA) at various reactant ratios and temperatures. Palladium supported alumina (Pd/Al2O3) was used as catalyst. Five grams of NPMIDA was added into a-500 mL three neck flask, and 85 mL aquadest was poured into it. Then, 1 mL H2O2 was added into the three neck flask every 20 minutes.. The product was vacuum-filtered and reacted with 130 mL ethanol. Separation of glyphosate was performed by filtering and washing it with ethanol and diethyl ether. The purity of glyphosate product was analyzed using UV/Vis spectrometer.
Keywords: glycine, oxidation, noble metal catalyst
oai:jurnal.ugm.ac.id:article/567
2012-05-01T03:49:41Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/567
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Jurnal Rekayasa Proses
Vol 3, No 2 (2009); 50-56
Penentuan Rasio Optimum Campuran CPO: Batubara Dalam Desulfurisasi dan Deashing Secara Flotasi Sistem Kontinyu
Aladin, Andi
2012-05-01 20:09:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/567
Salah satu problem penggunaan batubara Indonesia adalah kandungan sulfur dan abu yang relatif tinggi sehingga dapat berdampak pada kerusakan alat pembakar dan pencemaran lingkungan. Flotasi merupakan salah satu metode untuk mereduksi kandungan sulfur (anorganik) dan abu batubara. Penelitian desulfurisasi dan deashing batubara asal daerah Mallawa (Sulawesi) dilakukan dalam sebuah alat kolom flotasi dengan sistem kontinyu. Diamati beberapa variabel flotasi yang dapat memberikan hasil desulfurisasi yang maksimum, diantaranya adalah variabel rasio campuran surfaktan CPO (Crude Palm Oil) terhadap bahan batubara, dibahas dalam artikel ini. Diperoleh rasio campuran optimum adalah 1:4, berdasarkan kondisi optimum variabel lain yang telah diperoleh sebelumnya yaitu waktu tinggal 60 menit, laju alir udara 1,22 liter/menit, pH 6,5 dan ukuran partikel batubara 169 m. Pada kondisi optimum ini kandungan sulfur batubara dapat direduksi dari 3,3% menjadi 0,93% atau recovery sulfur 72% dan kandungan abu dapat diturunkan dari 11,25% menjadi 9,75% dengan nilai kalor dapat dipertahankan 6000 kkal/kg. Batubara hasil desulfurisasi dan deashing ini telah memenuhi kriteria untuk digunakan sebagai bahan bakar di industri.
Kata kunci: abu, sulfur, flotasi, nilai kalor, kontinyu, rasio CPO:Batubara
The problem related to the utilisation of Indonesian coal is the high sulphur and ash contents of the coal which may defect the combustor units and pollute the environment. Flotation is one of the methods to reduce the inorganic sulphur and ash in coal. Research on desulphurisation and deashing of coal from Mallawa (Sulawesi) was performed in a continuous flotation column. Variables which give maximum desulphurisation were studied and covered in this article, e.g. mixing ratio of crude palm oil (CPO) surfactant to coal. It was found that optimum mixing ratio of CPO to coal was 1:4, based on optimum conditions previously determined, i.e. resident time of 60 minutes, air flow rate of 1.22 l/min, pH 6.5 and coal particle size of 169 m. In these optimum conditions, the sulphur content was reduced from 3.3% to 0.93% or 72% sulphur recovery, while the ash content was reduced from 11.25% to 9.75%, the calorific value was maintained at 6000 kcal/kg. The desulphurised and deashed coal meets the specification criteria of the industrial fuel.
Key words: ash, sulphur, continuous flotation, caloric valve, ratio CPO:coal
oai:jurnal.ugm.ac.id:article/568
2012-05-01T04:07:17Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/568
2012-05-01T04:07:17Z
Jurnal Rekayasa Proses
Vol 4, No 1 (2010); 1-6
Modifikasi Pati Ketela Pohon Secara Kimia dengan Oleoresin dari Minyak Jahe
Retnowati, Diah Susetyo
Kumoro, Andre Cahyo
Budiyati, Sri
2012-05-01 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/568
Modifikasi pati akhir-akhir ini banyak dikembangkan dan dipakai untuk keperluan industri makanan, kertas dan tekstil. Modifikasi pati, khususnya secara kimia dilakukan untuk memperbaiki sifat-sifat fungsional pati, terutama jika untuk keperluan bahan dasar makanan. Modifikasi pati ketela pohon dilakukan dengan mereaksikan suspensi pati dengan minyak jahe yang mengandung zat aktif gingerol pada suhu kamar. Hasil percobaan modifikasi menunjukkan bahwa meningkatnya perbandingan antara pati/air/minyak jahe (b/v/v), menghasilkan pati termodifikasi dengan swelling power, kelarutan dan kerapatan cross-link yang lebih tinggi. Pada komposisi pati terhadap air dan minyak jahe, 300:400:0,4 (b/v/v) menghasilkan pati termodifikasi yang cocok digunakan sebagai bahan pengemas makanan yang dapat dimakan (edible food packaging) dengan nilai swelling power, kelarutan dan kerapatan cross-link adalah 7,3 kali; 6,662 mg/mL dan 780,69 rantai/cm3. Sedangkan komposisi pati:air:miyak jahe sebesar 300:300:0,3 (b/v/v) merupakan komposisi terbaik untuk menghasilkan pati termodifikasi sebagai bahan pangan dengan nilai swelling power, kelarutan dan kerapatan cross-link berturut-turut adalah 8,96 kali; 10,55 mg/mL, 203,85 rantai/cm3. Hasil analisis dengan scanning electron microscopy (SEM) menunjukkan bahwa modifikasi pati ketela pohon dengan teknik cross-linking ternyata tidak mengubah struktur permukaan butir pati.
Kata kunci: reaksi suspensi, pati ketela pohon, gingerol, swelling power, cross-link
Recently, starch modifications have been developed and are applied for food, paper and textile industries. In general, chemical modification has been done to improve starch functionality, especially for bread, cake and snack making. In the present work, suspension method was used to modify cassava starch by gingerol of crude ginger rhizome extract at room temperature. The effect of starch/water/gingerol (w/v/v) ratio on swelling power, water solubility, and cross-link density of the modified starch was investigated. In addition, scanning electron microscopy (SEM) analysis were also conducted to observe possible structural changes of the resulting starch. The experimental results showed that reactant composition that had a starch/water/gingerol (w/v/v) ratio of 300:400:0.4 produced modified starch suitable for edible coating with swelling power of 7.3 times, solubility of 6.662 mg/mL and cross-link density of 780.69 chains/cm3. Meanwhile, reactant having starch/water/gingerol (w/v/v) ratio of 300:300:0.3 produced modified starch that could be used for food with swelling power, solubility and cross-linking density of 8.96, 10.55 mg/mL and 203.85 chains/cm2, respectively. The cross-link densities achieved in this modification process were high and reproducible that indicated a strong interaction between starch and gingerol molecules in water as dispersant. However, there were no noticeable changes found from the micrograph of the SEM analysis on the external surface of the cassava starch.
Keywords: suspension method, cassava starch, gingerol, swelling power, cross-link
oai:jurnal.ugm.ac.id:article/569
2012-05-01T04:07:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/569
2012-05-01T04:07:18Z
Jurnal Rekayasa Proses
Vol 4, No 1 (2010); 7-12
Penjerapan Ion Logam Cadmium dalam Larutan Encer Menggunakan Baggase Fly Ash Teraktivasi
Helsanggi, Martha
Prasetya, Agus
2012-05-01 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/569
Bagasse fly ash (BFA) dapat digunakan sebagai adsorben berbagai macam logam berat seperti Cd2+ yang terlarut dalam air. Untuk dapat digunakan sebagai media penjerap BFA perlu lebih dahulu diaktivasi. Penelitian mempelajari pengaruh berbagai jenis aktivasi terhadap kemampuan adsorpsi BFA belum banyak dilakukan. Pada penelitian ini BFA diaktivasi menggunakan larutan HCl 1N dan H2O2 pada berbagai konsentrasi 0,01N, 0,02N, dan 0,05N. BFA teraktivasi kemudian digunakan untuk menjerap Cd2+. Pada penelitian ini juga dipelajari pengaruh suhu terhadap jumlah Cd2+ yang teradsorpsi. Hasil penelitian menunjukkan bahwa kualitas BFA teraktivasi H2O2 lebih baik dibandingkan BFA awal. Sementara itu, aktivasi dengan larutan HCl menyebabkan penurunan kualitas penjerapan. Hasil penelitian menunjukkan bahwa semakin tinggi suhu maka semakin sedikit Cd2+ yang terjerap.
Kata kunci: bagasse fly ash, penjerapan, aktivasi, H2O2, ion kadmium
Bagasse fly ash is frequently used as an adsorbent for various heavy metals such as Cd2+ dissolved in water. Activation procedure is generally required preceding adsorption using BFA. Investigation of different activation treatments and the influences on BFA adsorption capacity is still scarce. In the present study, BFA was activated in HCl 1 N solution and in H2O2 solution at different concentrations of 0.01 N, 0.02 N and 0.05 N. The activated BFA was then used for adsorption of water containing Cd2+. Also, the effect of temperature on the adsorption was part of the study. Experimental results indicated that H2O2 activated BFA showed superior adsorption properties compared with the unmodified BFA (raw BFA). Meanwhile, activation treatment in HCl solution caused a decrease in adsorption quality. The results also showed that temperature increase would lead to a decrease in adsorption capacity.
Keywords: bagasse fly ash, adsorption, activation, H2O2, ionic cadmium
oai:jurnal.ugm.ac.id:article/570
2012-05-01T04:07:18Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/570
2012-05-01T04:07:18Z
Jurnal Rekayasa Proses
Vol 4, No 1 (2010); 13-18
Peningkatan Kualitas Pembakaran Biomassa Limbah Tongkol Jagung sebagai Bahan Bakar Alternatif dengan Proses Karbonisasi dan Pembriketan
Surono, Untoro Budi
2012-05-01 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/570
Tongkol jagung merupakan limbah pertanian yang banyak dijumpai di Indonesia yang dapat diolah menjadi salah satu bahan bakar padat alternatif. Karbonisasi (pirolisis) yang diikuti dengan pembriketan merupakan salah satu cara yang dapat digunakan untuk mengolah biomasa menjadi bahan bakar padat. Penelitian ini mempelajari pengaruh suhu selama proses karbonisasi dan tekanan pada saat pembriketan terhadap sifat pembakaran briket dari tongkol jagung. Pada penelitian ini, proses karbonisasi dilakukan pada suhu 220ºC, 300ºC dan 380ºC sementara proses pembriketan dilakukan pada tekanan 24,4 MPa, 48,8 MPa, 73,2 MPa, dan 97,6 MPa. Hasil penelitian menunjukkan bahwa proses karbonisasi yang dilakukan dapat meningkatkan kandungan karbon dan nilai kalor briket dari tongkol jagung. Kondisi operasi karbonisasi terbaik diperoleh pada suhu 380°C, sementara untuk pembriketan dilakukan pada 97,6 MPa yang dapat menaikkan kadar karbon sampai 67% dan nilai kalor sampai 65%. Proses karbonisasi yang dilakukan dapat mengurangi emisi CO dan laju pembakaran. Hasil penelitian juga menunjukkan bahwa penekanan yang tinggi selama pembriketan juga dapat mengurangi emisi CO dan laju pembakaran.
Kata kunci: bahan bakar alternatif, biomasa, briket, karbonisasi, pembakaran, tongkol jagung
Corn cob is one of potential agricultural wastes in Indonesia that can be processed into an alternative solid fuel. Carbonization (pyrolysis) followed by briquetting is one of the methods that can be applied to process biomass into solid fuels. This work investigated the influence of carbonization temperature and briquetting pressure on combustion characteristic of corn cobs biomass. In this work, carbonization was carried out at three different temperatures, i.e. 220ºC, 300ºC and 380ºC, while briquetting process was prepared using four pressure variations, i.e. 24.4 MPa, 48.8 MPa , 73.2 MPa and 97.6 MPa. The results showed that carbonization process of corn cobs increased the fixed carbon content and the heating value. The best operating condition for carbonization and briquetting process were obtained at temperature of 380ºC and pressure of 97.6 Mpa that could increase the fixed carbon content and the heating value up to 67% and 65% respectively. Carbonization process could reduce CO emission and combustion rate. It was found that a high briquetting pressure resulted in low combustion rate and CO emission.
Keywords: alternative fuel, biomass, briquetting, carbonization, combustion, corn cobs
oai:jurnal.ugm.ac.id:article/571
2012-06-14T08:07:29Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/571
2012-06-14T08:07:29Z
Jurnal Rekayasa Proses
Vol 4, No 1 (2010); 19-24
Pemodelan dan Simulasi Kinetika Reaksi Alkoholisis Minyak Jarak Pagar (Jatropha Curcas) dengan Katalisator Zirkonia Tersulfatasi
Rustamaji, Heri
Sulistyo, Hary
Budiman, Arief
2012-05-01 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/571
Biodiesel berhasil diproduksi dengan alkoholisis minyak jarak menggunakan katalisator zirkonia tersulfatasi. Proses alkoholisis dilakukan dalam suatu reaktor batch yang dilengkapi dengan pemanas, termokopel, pengaduk, termostat, dan pengambil sampel. Reaktor batch diisi dengan minyak jarak pagar, metanol dan katalisator. Reaksi selanjutnya dilakukan selama 120 menit dan sampel diambil setiap 15 menit. Model kinetika reaksi kimia disusun dan diselesaikan dengan MATLAB. Nilai faktor frekuensi tumbukan untuk reaksi tiga tahap adalah 5,13 x 103; 5,682 x 103, dan 2,534 x 103 (cm3/mgek) (cm3/g.kat/min). Sementara itu, nilai energi aktivasi reaksi berturut-turut adalah 4.176; 4.309,809 dan 6.018,623 kal/mol. Hasil simulasi menunjukkan bahwa tahap pengurangan trigliserida menjadi digliserida adalah tahap paling cepat dan tahap pengurangan monogliserida menjadi gliserol adalah tahap paling lambat.Kata kunci: minyak jarak pagar, alkoholisis, model kinetika reaksi, katalisator asam padatJatropha oil is a very potential source of biodiesel fuel that can be processed through alcoholysis. In the present work, a study on alcoholysis of Jatropha oil with the use of solid acid catalyst was conducted in a wellmixed batch reactor. The study involved varying reaction temperatures of 100°C to 140°C, ethanol-oil molar ratio of 9, agitation speed of 1000 rpm and catalyst loading of 3% with respect to the oil. The reaction was carried out for 120 minutes; meanwhile samples were taken from the reactor every 15 minutes for glycerol analysis. In order to predict kinetics parameter of the alcoholysis reaction, a mathematical model of consecutive reactions was developed. The Matlab software was used to solve the simultaneous differential equations. Over the range of variables used in the experiment, the mathematical model was able to fit the experimental data quite well. The calculation results showed that the values of collision frequency factor for the consecutive reactions are 5.13 x 103; 5.682 x 103, and 2.534 x 103 (cm3/mgek) (cm3/g.cat/min). Meanwhile, the activation energies for the consecutive reaction are 4,176; 4,310 and 6,019 cal/mol. Keywords: jatropha curcas, methanolysis, kinetics modeling, solid acid catalyst
oai:jurnal.ugm.ac.id:article/572
2017-03-01T05:50:12Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/572
2017-03-01T05:50:12Z
Jurnal Rekayasa Proses
Vol 4, No 1 (2010); 25-29
Pengaruh Pretreatment Jerami Padi pada Produksi Biogas dari Jerami Padi dan Sampah Sayur Sawi Hijau Secara Batch
Herawati, Dewi Astuti
Wibawa, Andang Arif
2010-05-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/572
Dalam dekade terakhir, tingkat konsumsi energi semakin tinggi, sedangkan sumber energi fosil terbatas. Diperlukan usaha-usaha untuk mendapatkan energi terbarukan. Di sisi lain, limbah pertanian dan sampah pasar melimpah dan dapat dibuat biogas yang merupakan energi terbarukan. Tujuan penelitian ini adalah untuk mengetahui pengaruh pretreatment jerami terhadap yield biogas dan kadar metana. Sampah sayuran sawi hijau (Brassica Juncea) dan jerami padi dicampur dengan komposisi tertentu sampai diperoleh perbandingan molar C/N = 20. Starter inokulum dari cairan hasil biodigester dimasukkan ke dalam erlenmeyer yang kemudian ditambahkan air sehingga volume totalnya menjadi 350 ml. pH awal campuran diukur dan campuran dialiri gas N2 supaya kondisi anaerob tercapai sementara erlenmeyer dalam keadaan tertutup rapat. Fermentasi dilakukan pada suhu 35°C. Volume biogas dan pH diukur setiap hari sementara kadar metana dianalisis setiap tujuh hari. Proses fermentasi diamati selama 49 hari. Hasil terbaik diperoleh dari jerami ukuran 0,5 cm yang dikenakan perlakukan awal penambahan EM-4, dimana hasil yield biogas rata-rata 0,03 L/g VS pada hari ke-21. Kadar metan tertinggi sebesar 64,78% dihasilkan pada hari ke-28 diperoleh dari jerami padi yang dibuat serbuk. Perlakuan awal jerami padi secara biologis dengan penambahan EM-4 terbukti dapat meningkatkan yield biogas sebesar 188,48%. Kata kunci: jerami padi, sawi hijau, EM-4, biogas, metana, yield biogas In the recent decades, population growth has increased energy consumption level. On the other hand, fossil energy sources are very limited and therefore the need to seek renewable energies as alternatives is inevitable. Agricultural and traditional market wastes can be used to produce biogas as renewable energy. The objectives of this study was to investigate the potential of rice straws and green mustard (Brassica Juncea) to produce biogas and the effect of pretreatment on the biogas production. Vegetable waste of green mustard and rice straws were mixed so that the C to N ratio was 20. Inoculums starter taken from bio-digester effluent was put into an erlenmeyer and water was then added to a total volume of 350 ml. Initial mixture pH was measured and nitrogen was fed to the reactor to get anaerobic condition while the erlenmeyer was isolated. Fermentation was conducted at temperature of 35°C. Volume and pH of the resulting biogas were measured everyday, while the methane content was analyzed every seven days. The fermentation process was observed for 49 days. Experimental results showed that the highest result was obtained from rice straw that was pretreated by adding EM-4 with the average biogas yield of 0,030 L/g VS after 21 days. The highest methane content was obtained after 28 days with a purity of 64,78% from the powdered rice straw. The experimental results showed that the rice straw pretreated with EM-4 addition could increase biogas yield by 188,48%. Keywords: rice straw, green mustard, EM-4, biogas, methane, yield of biogas
oai:jurnal.ugm.ac.id:article/1887
2013-05-20T06:51:04Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1887
2013-05-20T06:51:04Z
Jurnal Rekayasa Proses
Vol 4, No 2 (2010); 30-34
Optimasi Proses Nitrasi pada Pembuatan Nitro Selulosa dari Serat Limbah Industri Sagu
Purnawan, Purnawan
2013-05-20 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1887
Proses pembuatan selulosa nitrat dari serat sagu dilakukan dengan dua tahapan proses yaitu proses delignifikasi dan proses nitrasi. Penelitian ini bertujuan untuk mempelajari proses nitrasi selulosa menjadi nitro selulosa. Sebelum dinitrasi, selulosa serat sagu dibersihkan dari kandungan ligninnya dengan proses soda nitrat memakai asam nitrat dan natrium hidroksida. Proses nitrasi menggunakan asam campuran yang terdiri dari asam nitrat dan asam sulfat sebagai katalisator. Proses dilakukan dalam labu leher tiga yang dilengkapi pengaduk dan pengatur suhu. Pada penelitian ini dipelajari pengaruh waktu reaksi, perbandingan selulosa dengan asam campuran dan perbandingan asam sulfat dengan asam nitrat. Hasil penelitian menunjukkan bahwa proses nitrasi akan memberikan hasil terbaik pada waktu reaksi 1,5 jam, perbandingan selulosa – asam campuran 1:20 serta perbandingan asam sulfat – asam nitrat 1:5. Pada kondisi ini diperoleh yield sebanyak 151,22% dengan kandungan nitrogen sebanyak 13,39% yang mendekati kadar nitrogen maksimum teoritis sebesar 14,14%. Kata kunci: delignifikasi, nitrasi, nitroselulosa, kadar nitrogen Nitrocellulose production from sago fibers was conducted in two steps, i.e. delignification and nitration processes. This work studied the nitration process of sago fiber cellulose. Before nitration, the lignin was removed using the nitrate soda process utilizing nitric acid and sodium hydroxide. The nitration process used an acid solution consisting of nitric acid and sulfuric acid as a catalyst. The process was carried out in a three neck flask equipped with stirrer and temperature control. The effects of reaction time, nitric acid concentration, and sulfuric to nitric acid ratio were investigated. The results showed that the best operating conditions obtained for the reaction time, cellulose to mixed acid ratio and sulfuric to nitric acid ratio were 1.5 hours, 1:20 and 1:4 respectively in which the product yield and nitrogen content were found to be 151.22% and 13.39%. This nitrogen content was close to the theoretical maximum nitrogen content of 14.14%. Keywords: delignification, nitration, nitrocellulose, nitrogen content.
oai:jurnal.ugm.ac.id:article/1888
2013-05-20T01:33:50Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1888
2013-05-20T01:33:50Z
Jurnal Rekayasa Proses
Vol 4, No 2 (2010); 35-39
Pengembangan dan Pengujian Inokulum Untuk Pengomposan Limbah Tandan Kosong Kelapa Sawit
Sentana, Suharwaji
Suyanto,
Subroto, M.A.
Suprapedi,
Sudiyana,
2013-05-20 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1888
Limbah tandan kosong kelapa sawit (TKKS) yang jumlahnya mencapai 23% dari tandan buah segar, mengandung unsur hara makro dan mikro yang penting bagi pertumbuhan tanaman. Pada saat ini limbah tersebut belum dimanfaatkan secara optimal. Tujuan penelitian ini adalah untuk mengembangkan dan menguji inokulum yang dapat digunakan untuk pembuatan kompos dari limbah tandan kosong kelapa sawit. Inokulum merupakan campuran bakteri dan jamur yang diisolasi dari limbah tandan kosong kelapa sawit. Isolat kemudian ditumbuhkan pada media pertumbuhan tertentu dan difermentasikan. Pengujian inokulum dilakukan pada skala laboratorium dengan cara sebagai berikut: dua kilogram tandan kosong kelapa sawit yang telah dicacah sepanjang 2 cm dimasukkan ke dalam wadah, kemudian diinokulasi dengan inokulum pada dosis 500 dan 1000 ml/ton. Percobaan diulang hingga tiga kali. Selama percobaan kelembaban relatif dijaga tetap 60% dan suhu diamati hingga proses pengomposan selesai. Kompos yang dihasilkan dianalisis kadar air, karbon, nitrogen, fosfor, kalium, dan magnesium. Pada penelitian ini telah berhasil dikembangkan inokulum yang terdiri atas campuran bakteri dan jamur dinamakan ”Indigenous Microbial Consortium” dan dapat dipergunakan untuk membuat kompos dengan kualitas yang memenuhi standar.
Kata kunci: kompos, limbah tandan kosong kelapa sawit, inokulum, konsorsium mikroba.
Empty palm oil bunch waste is about 23% of the fresh bunches which is rich with important macro and micro nutrients for plant growth. However, those have not been optimally utilized. The objective of this experiment was to develop and to evaluate the inoculums which could be used to make compost from empty palm oil bunch wastes. The inoculums consisted of fungies and bacteria isolated from the empty palm oil bunches. The isolates were then grown and fermented on to a particular media. The inoculums were then evaluated at laboratory scale according to the following methods. About 2 kg of 2 cm long crushed empty palm oil bunches were put in particular places and were then inoculated by the inoculums at a dosage of 500 and 1000 ml/ton of wastes. The experiment was done at triplicates and the relative humidity during the experiment was kept constant at 60%, and temperature was recorded until the end of the experiment. Water, carbon, nitrogen, phosphor, potassium, and magnesium contents of the composts were analysed. The inoculums that consisted of fungies and bacteria were successfully developed and it was called “Indigenous Microbial Consortium”. The inoculums could be used to make good quality of composts.
Keywords: compost, empty palm oil bunches, inoculums, microbial consortium.
oai:jurnal.ugm.ac.id:article/1889
2013-05-20T01:33:50Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1889
2013-05-20T01:33:50Z
Jurnal Rekayasa Proses
Vol 4, No 2 (2010); 40-44
Extraction and Modification of Gum from Cashew Tree Exudates Using Wheat Starch and Glycerine
Kumoro, Andri Cahyo
Retnowati, Diah Susetyo
Budiyati, Catarina Sri
2013-05-20 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1889
Penelitian ini bertujuan untuk mengekstrak getah pohon mete dan memodifikasi sifatnya untuk dapat digunakan sebagai senyawa pembantu proses pengeringan menggantikan fungsi getah Arab. Dengan menggunakan getah mete termodifikasi dari penelitian ini, permasalahan biaya pada proses pengeringan jus buah dengan spray dryer dapat diatasi. Getah pohon mete dipungut dan diendapkan dari larutan hasil penyadapan dengan bantuan etanol sebagai antisolvent. Dalam penelitian ini gliserin dan pati gandum digunakan sebagai bahan tambahan untuk memodifikasi sifat getah. Hasil penelitian menunjukkan bahwa getah pohon mete termodifikasi yang dihasilkan memiliki kualitas yang baik dan kesamaan sifat dengan getah Arab.
Kata kunci : getah pohon mete, getah Arab, modifikasi, pati, gliserin
The objectives of this research were to extract cashew tree gum (CTG) from cashew tree exudates and to modify it into a new drying aid, which can act as a substitute for Arabic gum. The cost problem faced in the spray drying of fruit juices is expected to be solved with the use of modified CTG as a replacement of Arabic gum. The CTG was extracted and precipitated from its raw cashew exudates solution with the help of ethanol as antisolvent. Glycerine and wheat starch were the additives used in the modification of the gum. The good quality of modified CTG was obtained based on their close similarity to Arabic gum properties.
Keywords: CTG, Arabic gum, modification, starch, glycerine
oai:jurnal.ugm.ac.id:article/1890
2013-05-20T06:59:10Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1890
2013-05-20T06:59:10Z
Jurnal Rekayasa Proses
Vol 4, No 2 (2010); 45-50
Teknologi Co-processing : Solusi Alternatif Mereduksi Bahan Bakar Fosil dan Gas CO2 di Industri Semen Indonesia
Pamungkas, Yulius
2013-05-20 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1890
Teknologi co-processing dalam industri semen didefinisikan sebagai teknik pemakaian kembali limbah suatu industri sebagai substitusi bahan bakar fosil dan bahan baku semen (bahan galian C) dengan tujuan untuk memanfaatkan nilai energi dan nilai bahan yang masih terkandung di dalam limbah tersebut. Di Eropa teknologi co-processing dikenal juga sebagai co-incinerator dan telah berkembang pesat. Sementara di Indonesia pemusnahan limbah masih dilakukan terpisah dan menggunakan teknologi incenerator yang masih menghasilkan residu yang harus dilakukan pemusnahan kembali. Industri besar yang menggunakan sistem reaktor pembakaran seperti semen, baja, kapur, pembangkit listrik sangat mungkin memanfaatkan teknologi co-processing dalam strategi jangka panjangnya dalam mengelola pemakaian bahan bakar dan bahan baku berupa bahan galian C. Teknologi co-processing yang dilakukan secara konsisten dapat membantu penghematan energi fosil, mengurangi pemanasan global yang diakibatkan oleh peningkatan emisi CO2 dan mempunyai dampak lingkungan yang lebih bersih dalam hal pemusnahan limbah industri. Dalam industri semen, kunci keberhasilan teknologi co-processing adalah penentuan lokasi dan sistem pengumpanan limbah, konsistensi kualitas nilai energi dan nilai bahan dari limbah dan pengelolaan limbah yang memperhatikan sistem Kesehatan dan Keselamatan Kerja dan Lingkungan Hidup (K3LH). Hal yang perlu diperhatikan dalam penerapan teknologi co-processing adalah komposisi, bentuk dan ukuran serta kandungan air dan zat pengotor yang bervariasi antara berbagai jenis limbah agar tidak mempengaruhi kestabilan operasi dan kualitas produk. Kata kunci: co-processing, incinerator, energi, emisi CO2, limbah Co-processing technology in cement industry is defined as the technology to use wastes such as used oil, scrap tires and other organic wastes in order to reduce fossil fuel consumption. This technology also allows the utilization of material elements contained in the wastes such as alumina, silica and iron to substitute some of raw materials used in cement industry. In Europe, this technology is also known as co-incinerator and being used widely. Hazardous waste disposal in Indonesia is done traditionally using incineration technology. The incineration technology may result toxic ashes that require further treatment before it can be dumped into a secure landfill. Big industries that have combustion reactor system with high temperature such as cement industry, steel industry and power generation could utilize co-processing technology as their long term strategy to reduce both fossil and raw material consumptions. If this technology can be consistently applied in the big industries, it has big potential to reduce the use of fossil fuel (and global warming) and to lower the risk due to traditional hazardous waste disposal. Some keys for successful implementation of the co-processing technology in cement industries include the appropriate selection of feeding method and location; consistency in energy content of the wastes and waste treatments that are compliance with safety and environmental laws. Care should be taken in the use of this technology due to the variation in composition, shape and size of the wastes and its water and impurities content so that these variations would not affect the plant operation stability and the product quality. Keywords: co-processing, incinerator, energi, CO2 emission, waste
oai:jurnal.ugm.ac.id:article/1891
2013-05-20T07:13:49Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1891
2013-05-20T07:13:49Z
Jurnal Rekayasa Proses
Vol 4, No 2 (2010); 51-55
Pengaruh Temperatur Heat-Treatment terhadap Kekerasan dan Struktur Mikro Paduan Al-Fe-Ni
Al Hasa, M. Husna
2013-05-20 20:10:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1891
Fabrikasi elemen bakar antara lain meliputi proses deformasi dan annealing. Proses annealing akan mengakibatkan perubahan sifat logam. Pemanasan pada suhu tersebut akan mempengaruhi sifat mekanik, sifat fisik dan sifat termal logam. Penelitian ini bertujuan untuk mendapatkan informasi pengaruh suhu terhadap sifat bahan terutama kekerasan dan fasa paduan logam. Proses annealing dilakukan di atas suhu rekristalisasi dan di bawah suhu titik cair logam, yaitu pada 450°C, 500°C dan 550°C. Pengujian kekerasan bahan struktur berbasis aluminium Al-Fe-Ni dilakukan dengan menggunakan metoda Vicker. Pengamatan mikrostruktur dilakukan dengan metalografik-optikal dan analisis besaran struktur butir mikrostruktur menggunakan metode DAS. Analisis struktur fasa dilakukan berdasarkan pola difraksi sinar-x. Hasil pengujian sifat kekerasan menunjukan paduan Al-Fe-Ni dengan pemanasan pada 450°C, 500°C dan 550°C masing-masing adalah 53 HV, 60 HV dan 55 HV. Kekerasan paduan mengalami kenaikan dari 53 HV pada suhu 450°C menjadi 60 HV pada suhu 500°C, dan mengalami penurunan di atas suhu 500°C, menjadi 55 HV pada 550°C. Hasil pengamatan metalografik-optikal memperlihatkan mikrostruktur paduan mengalami perubahan seiring dengan meningkatnya suhu. Mikrostruktur memperlihatkan bentuk struktur butir dendrit yang cenderung mengecil pada 500°C. Hasil analis pola difraksi menunjukkan pembentukan fasa θ (FeAl3), fasa k (NiAl3) dan τ (FeNiAl9) cenderung meningkat pada suhu 500°C. Paduan logam yang terbentuk akibat pemanasan pada suhu 450°C didominasi oleh keberadaan fasa k (NiAl3) dan fasa τ (FeNiAl9). Sementara itu, pada suhu 550°C terdapat kecenderungan pembentukan fasa tunggal τ (FeNiAl9). Pada kisaran suhu yang dipelajari, sifat kekerasan paduan Al-Fe-Ni dipengaruhi oleh perlakuan suhu. Kekerasan paduan Al-Fe-Ni tertinggi diperoleh pada suhu pada 500°C. Kata kunci: annealing, heat-treatment, kekerasan, fasa, paduan Al-Fe-Ni Fuel element manufacturing includes deformation process and annealing. Annealing process will change the properties of the metal. Thermal treatment will affect the nature of mechanical, physical and thermal properties of metal. This research aims to investigate the effects of thermal treatment on the properties of the materials, especially the hardness and phase of the metal alloy. Annealing process was carried out above recrystallization temperature and below melting point of the metal, e.g. 450°C, 500°C and 550°C. The hardness of Al-Fe-Ni alloy was determined by using Vickers method. The microstructure was observed by optical microscopy and grain microstructure was analyzed by DAS method. The phase structure analysis was done based on x-ray diffraction pattern. Heat treatment at three different temperatures of 450°C, 500°C and 550°C resulted in material hardness of 53 HV, 60 HV and 55 HV, respectively. Between 450°C - 500°C, the hardness of Al-Fe-Ni increased with increasing annealing temperature. On the other hand, above 500°C, the alloy hardness decreased with increasing annealing temperature. Optical metallographic observation results showed that the microstructure tends to change along with temperature increase. The microstructure of the Al-Fe-Ni alloy showed grain structure of dendritic that tends to wane at 550°C. Diffraction pattern analysis indicated that the formation of phase tended to increase at 500°C. The x-ray diffraction pattern also showed the tendency of formation of k (NiAl3) and τ (FeNiAl9) phase at 450°C. At 500°C the tendency was to form the phase τ (FeNiAl9), θ (FeAl3) and phase k (NiAl3). Meanwhile, τ (FeNiAl9) phase was preferably to form at 550°C. It was found that in the range of observed temperature, the maximum hardness of Al-Fe-Ni alloy was obtained at 500°C. Keywords: annealing, heat-treatment, hardness, phase, Al-Fe-Ni alloy
oai:jurnal.ugm.ac.id:article/1892
2013-05-20T07:36:39Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1892
2013-05-20T07:36:39Z
Jurnal Rekayasa Proses
Vol 5, No 1 (2011); 1-9
Kinetika Reaksi Alkyd Resin Termodifikasi Minyak Jagung dengan Asam Phtalat Anhidrat
Heriyanto, Heri
Rochmadi, Rochmadi
Budiman, Arief
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1892
Reaksi esterifikasi anhidrida phtalat dengan monogliserida merupakan reaksi kondensasi membentuk polimer dengan rantai linier. Penelitian ini bertujuan untuk mempelajari kinetika reaksi alkid resin termodifikasi minyak jagung tanpa menggunakan katalis. Proses penelitian ada dua tahap yaitu tahap pertama reaksi alkoholisis dan tahap kedua reaksi esterifikasi. Tahap alkoholisis diawali dengan mereaksikan minyak jagung dan gliserol dengan perbandingan molar 1:2 pada suhu 250°C. Sampel diambil pada selang waktu 30 menit selama 3 jam untuk dianalisis kadar gliserol bebasnya dengan metode iodometri (FBI-AO2-03). Tahap esterifikasi adalah mencampurkan anhidrida phtalat ke dalam reaktor batch dengan perbandingan molar gliserol : anhidrida phtalat 3:2. Sampel dianalisis kadar gugus OH- dengan metode asetat anhidrida. Peubah-ubah yang dipelajari meliputi variasi suhu dari 230°C – 260°C dan variasi perbandingan ekivalen OH/COOH dari 1 – 1,25. Berdasarkan hasil penelitian diambil kesimpulan bahwa minyak jagung dan gliserol dapat dialkoholisis tanpa menggunakan katalis pada kisaran suhu 230°C – 260°C. Pengaruh suhu terhadap konstanta kecepatan reaksi dinyatakan dengan persamaan Arrhenius adalah sebagai berikut : k1=1,4647×104 exp (-8237,7/T) (g/mgek.men) k4=2,1398×109 exp (-14142/T) (g/mgek.men) Kata kunci: alkoholisis, esterifikasi, minyak jagung, gliserol, anhidrida phtalat Esterification of phthalic anhydrate with monoglyceride is a condensation reaction to form a linear chain polymer. The present work aimed at investigating reaction kinetics of alkyd resin modified with corn oil in the absence of catalyst. The work consisted of two steps i.e. alcoholysis and esterification. In the alcoholysis step, corn oil and glycerol were brought into reaction with a molar ratio of 1:2 at 250°C. Every 30 minutes during 3 hour reaction, reaction products were sampled to analyse the remaining free glycerol by iodometry method (FBI-AO2-03). In the esterification step, phthalic anhydrate was put in the batch reactor with a glycerol-phthalic anhydrate molar of 3:2. Samples were taken and the hydroxyl ions were analysed by acetate anhydrate method. The variables investigated in the present work were reaction temperatures varied from 230°C to 260°C and equivalent OH/COOH ratio from 1 to 1.25. Experimental results showed that alcoholysis of corn oil and glycerol could be carried out in a temperature range of 230°C to 260°C without the presence of catalyst. The effect of temperature on the reaction rate constant of monoglyceride and phthalic ester formation could be respectively written in the Arrhenius correlations as follows: k1 = 1.4647.104 exp (-8237.7/T) g/mgeq.min k4 = 2.1398.109 exp (-14142/T) g/mgeq.min Keywords: alcoholysis, esterification, corn oil, glycerol, phthalic anhydrate
oai:jurnal.ugm.ac.id:article/1893
2013-05-20T02:46:12Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1893
2013-05-20T02:46:12Z
Jurnal Rekayasa Proses
Vol 5, No 1 (2011); 10-16
Studi Eksperimental Pengendalian Korosi pada Aluminium 2024-T3 di Lingkungan Air Laut Melalui Penambahan Inhibitor Kalium Kromat (K2CrO4)
Wibowo, Waris
Ilman, Mochammad Noer
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1893
Aluminium paduan seri 2024-T3 banyak digunakan di industri manufaktur seperti pesawat terbang, otomotif, dan kapal laut karena aluminium merupakan logam ringan dan memiliki sifat mekanik yang baik. Namun demikian aluminium paduan 2024-T3 rentan terhadap korosi bila dioperasikan di lingkungan yang korosif, seperti air laut. Salah satu upaya untuk mengendalikan laju korosi adalah dengan penambahan inhibitor. Penelitian ini bertujuan untuk mempelajari pengaruh inhibitor kalium kromat (K2CrO4) dalam mengendalikan laju korosi Al 2024-T3 di lingkungan air laut. Pada penelitian ini, jenis inhibitor yang dipakai adalah kalium kromat (K2CrO4) yang ditambahkan di media air laut dengan variasi konsentrasi 0,1%; 0,3%; dan 0,5%. Selanjutnya laju korosi diukur dengan menggunakan metode sel potensial tiga elektroda dengan kalomel (Hg2Cl2) jenuh sebagai elektroda baku sedangkan elektroda tambahan digunakan platina (Pt). Sebagai data pendukung dilakukan uji komposisi, uji struktur mikro, uji kekerasan Vickers dan uji tarik. Hasil penelitian ini memperlihatkan bahwa laju korosi Al 2024-T3 di media air laut tanpa inhibitor sebesar 0,0216 mm/tahun. Penambahan inhibitor kalium kromat (K2CrO4) cenderung menurunkan laju korosi dan konsentrasi optimum tercapai pada 0,5% K2CrO4 ditandai dengan laju korosi minimum yaitu sebesar 0,0134 mm/tahun atau terjadi penurunan laju korosi sebesar 38%. Bentuk korosi yang terjadi berupa korosi sumuran (pitting corrosion) yang disebabkan karena rusaknya selaput pasif. Pada kasus ini inhibitor berfungsi menutup selaput pasif yang rusak tersebut sehingga dapat menghambat laju korosi.
Kata kunci: aluminium paduan, 2024-T3, air laut, korosi , inhibitor, K2CrO4
Aluminium alloy 2024-T3 is widely used in manufacturing industries such as aircraft, automotive and ship industries due to its light weight and good mechanical properties. However, aluminium alloy 2024-T3 is suffered from corrosion attack when it is operated in corrosive environment such as sea water. One of the corrosion control methods is inhibitor addition. The present investigation aimed to study the effect of K2CrO4 inhibitor on controlling corrosion rate in sea water. In this research, K2CrO4 was added to sea water environment with various concentrations, i.e. 0.1, 0.3 and 0.5%. Subsequently corrosion rates were measured using three-electrode potential technique with saturated calomel (Hg2Cl2) electrode as a reference electrode whereas the auxiliary electrode was platinum (Pt). Additional experiments including compositional analysis, microstructural examination, hardness measurement and tensile test were also carried out to gain better understanding to the mechanism in which corrosion attacks aluminium alloy 2024-T3. Experimental results showed that corrosion rate of aluminium alloy 2024-T3 in sea water without inhibitor is around 0.0216 mm/year. The additions of K2CrO4 inhibitor tended to reduce the corrosion rate until a minimum value was obtained, typically 0.0134 mm/year (or 38% decrease) as the amount of K2CrO4 was 0.5%. The type of corrosion observed in this investigation was pitting corrosion as a result of local damage in passive film. Inhibitor seemed to form thin protective film on metal surface hence reducing corrosion rate.
Keywords: aluminium alloy, 2024-T3, sea water, corrosion , inhibitor, K2CrO4
oai:jurnal.ugm.ac.id:article/1894
2013-05-20T02:46:12Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1894
2013-05-20T02:46:12Z
Jurnal Rekayasa Proses
Vol 5, No 1 (2011); 17-23
Performa Sistem Autocascade dengan Menggunakan Karbondioksida sebagai Refrigeran Campuran
Nasruddin,
Yuliono, Ardi
Syaka, Darwin Rio Budi
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1894
Sistem refrigerasi yang saat ini digunakan sebagian besar masih menggunakan refrigeran yang mengandung zat perusak ozon atau penyebab pemanasan global. Karena itu, diperlukan alternatif refrigeran alamiah, yang salah satunya adalah CO2. Namun tingginya tekanan CO2 membatasi penggunaanya pada sistem refrigerasi konvensional. Solusi untuk mengatasi hal itu, dengan biaya investasi yang relatif rendah, adalah dengan menggunakan sistem refrigerasi autocascade. Penelitian ini mempelajari sistem refrigerasi autocascade menggunakan beberapa variasi campuran CO2 (R744) dengan R12 untuk dibandingkan dengan campuran refrigerant alternatif ramah lingkungan yaitu campuran CO2 (R744) dengan R600a. Parameter yang dianalisa antara lain (1) suhu evaporasi, (2) suhu kondensasi, (3) suhu suction, (4) suhu discharge, (5) tekanan suction, dan (5) tekanan discharge. Hasil pengujian menunjukkan bahwa penambahan komposisi CO2 sebesar 10% atau lebih dalam sistem refrigerasi autocascade dapat menaikkan tekanan kerja sistem. Oleh karena itu, penambahan komposisi CO2 tersebut harus masih di dalam batas-batas toleransi tekanan kerja kompresor yang diijinkan.
Kata kunci: autocascade, refrigeran, CO2 , R12, R600a, kompresor
Most refrigeration systems today use refrigerant which causes ozone depletion or global warming. Therefore, alternative natural refrigerants are highly required. One potential candidate is CO2. However, high pressure of CO2 limits its application in conventional refrigeration system. To solve this problem, a low investment cost of autocascade refrigeration system is used. This research investigated autocascade refrigeration system using a mixture of CO2 (R744) and R12, in comparison with environmentally friendly refrigerant mixture of CO2 (R744) and R600a. The parameters analyzed were (1) evaporation temperature, (2) condensation temperature, (3) suction temperature, (4) discharge temperature, (5) suction pressure, and (5) discharge pressure. The experiment results showed that an increase of CO2 concentration by 10% or more in the autocascade refrigeration system could raise system pressure. Therefore, the increase of CO2 pressure should be within the allowable limit of the working pressure of the compressor.
Keywords: autocascade, refrigerant, CO2, R12, R600a, compressor
oai:jurnal.ugm.ac.id:article/1895
2013-05-20T02:46:12Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1895
2013-05-20T02:46:12Z
Jurnal Rekayasa Proses
Vol 5, No 1 (2011); 24-29
Analisis Eksperimental Fluks Kalor pada Celah Sempit Anulus Berdasarkan Variasi Suhu Air Pendingin Menggunakan Bagian Uji HeaTiNG-01
Riyono, Bambang
Indarto,
Habsari, Sinta Tri
Juarsa, Mulya
Kiswanta,
R., Ainur
S., Edy
P.W., Joko
H., Ismu
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1895
Eksperimen untuk mempelajari mekanisme perpindahan panas pendidihan pada celah sempit berdasarkan skenario kecelakaan parah PLTN TMI-2 perlu dilakukan untuk pemahaman terkait manajemen kecelakaan. Penelitian bertujuan untuk memperoleh nilai fluks kalor dan fluks kalor kritis (FKK) selama proses perpindahan panas pendidihan pada celah sempit anulus. Metode penelitian secara eksperimen menggunakan bagian uji HeaTiNG-01dengan fluida pendingin adalah air. Eksperimen dilakukan dengan memvariasikan suhu air pendingin pada suhu 75C, 85C dan 95C, dan memanaskan batang panas hingga mencapai suhu awal 650C. Kemudian proses pendidihan selama pendinginan direkam berdasarkan suhu transien pada batang panas. Data suhu digunakan untuk menghitung nilai fluks kalor dan wall superheat, hasilnya direpresentasikan melalui kurva didih. Hasil penelitian menunjukkan nilai FKK suhu pendingin 750C lebih rendah dibandingkan FKK suhu pendingin 85C dan 95C, dimana nilai FKK untuk suhu pendingin 85C dan 95C agak berdekatan. Nilai FKK maksimum untuk suhu 75C adalah 230 kW/m2, sedangkan untuk suhu 95C adalah 282 kW/m2. Meskipun demikian korelasi FKK terhadap posisi aksial batang panas pada berbagai variasi suhu mengikuti korelasi polynomial. Peristiwa pendidihan pada celah sempit tidak termasuk kategori didih kolam dengan membandingkan area didih film hasil eksperimen menggunakan korelasi Bromley.
Kata kunci : kecelakaan parah, anulus, fluks kalor, FKK, celah sempit, didih kolam
Experiment to investigate the mechanism of boiling heat transfer in a narrow gap on severe accident scenarios of TMI-2 nuclear power plant is necessary to develop the understanding of the related accident management.The present study aimed to obtain heat flux value and critical heat flux (CHF) during boiling heat transfer process in a narrow gap of annulus. The study was experimentally carried out using the HeaTiNG 01 test with water as cooling fluid which temperature was varied at 75C, 85C dan 95C. The rod was heated to 650C. The boiling process during cooling was investigated by recording the transient temperature of the heated rod. The data was used to calculate the heat flux and wall superheat which results were represented in a boiling curve. The experimental results showed that the CHF value of the cooling media at 75C was lower compared with that of at 85C and 95C. It was found that the values of CHF at 85C and 95C were close. The maximum CHF value at 75C was 230 kW/m2, while at 95C was 282 kW/m2. The CHF values at various position of heated rod was found to follow polynomial correlation. By comparing the boiling film areas from experimental results with that of Bromley correlation, it was concluded that boiling process in a narrow gap could not categorized as pool boiling process.
Keywords: severe accident, annulus, heat flux, CHF, narrow gap, pool boiling
oai:jurnal.ugm.ac.id:article/1896
2013-05-20T02:46:13Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1896
2013-05-20T02:46:13Z
Jurnal Rekayasa Proses
Vol 5, No 1 (2011); 30-34
Pembuatan Resin Phenol Formaldehyde Sebagai Prekursor Untuk Preparasi Karbon Berpori: Pengaruh Jenis Turunan Phenol Terhadap Karakteristik Resin dan Karbon
Nuryati,
Prasetyo, Imam
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1896
Resin phenolic merupakan hasil polikondensasi antara phenol (P) dengan formaldehyde (F). Penelitian ini bertujuan untuk mempelajari pembuatan resin phenol formaldehyde yang dimodifikasi dengan menambahkan reaktan turunan phenol seperti tersier butil phenol (T), resorcinol (R) dan hidroquinon (H). Resin yang dihasilkan digunakan sebagai prekursor pembuatan karbon berpori. Reaksi polimerisasi phenol formaldehyde dilakukan dalam reaktor berpengaduk pada suhu 90oC. KOH digunakan sebagai katalisator dan reaksi berlangsung 1-3 jam. Para Toluene Sulfonic Acid (pTSA) ditambahkan sebagai katalisator crosslinking. Proses pirolisis resin dilakukan pada suhu 800oC selama 1 jam untuk menghasilkan karbon berpori. Hasil karakterisasi dari keempat jenis resin tersebut menunjukkan bahwa densitas tertinggi adalah resin PF dan resin PFT, sebesar 1,18 g/ cm3. Resin PF memiliki kekerasan tertinggi yaitu sebesar 17,20 g/mm2. Hasil karakterisasi terhadap karbon menunjukkan bilangan iodin karbon PF sebesar 862,32 mg/g dan karbon PFT sebesar 794,16 mg/g. Karbon PF dan karbon PFT memiliki luas permukaan masing-masing sebesar 836,7 m2/g dan 720,7 m2/g.
Kata kunci: resin phenolic, karbon berpori, bilangan iodin, lebar permukaan
Phenolic resin is the product of polycondensation between phenol (P) with formaldehyde (F). This research aims to study synthesis of phenol formaldehyde resin modified by adding the reactant in the form of phenol derivatives, such as tertiary butyl phenol (T), resorcinol (R) and hydroquinone (H). The product is applied as precursor for making porous carbon. Reaction of phenol formaldehyde was carried out in a stirred reactor at temperature of 90oC for 1 to 3 hours. KOH was used as catalyst. Para Toluene Sulfonic Acid (pTSA) was added to the resin as a cross linking catalyst. Carbonization process was carried out by pyrolysis at the temperature of 800oC for 1 hour. The results showed that PF and PFT resins had high density of 1.18g/cm3. PF resin had the hardness value of 17.2 g/mm2. The iodine number of the PF and PFT carbon was 862.3 mg/g and 794.16 mg/g, respectively. The surface area of the PF and PFT carbons were 836.7m2/g and 702.7m2/g, respectively.
Keywords: phenolic resins, porous carbon, iodine number, surface area.
oai:jurnal.ugm.ac.id:article/1897
2013-05-20T03:20:25Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/1897
2013-05-20T03:20:25Z
Jurnal Rekayasa Proses
Vol 5, No 2 (2011); 35-39
Kinetika Reaksi Esterifikasi Gliserol dengan Asam Asetat Menggunakan Katalisator Indion 225 Na
Nuryoto,
Sulistyo, Hary
Rahayu, Suprihastuti, Sri
Sutijan,
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1897
Biodisel merupakan bahan bakar alternatif yang ramah lingkungan. Dengan semakin meningkatnya proses pembuatan biodiesel, maka akan diikuti dengan meningkatnya produk samping berupa gliserol. Untuk itu, usaha pengolahan gliserol menjadi produk lain harus dilakukan, agar nilai ekonomi gliserol makin meningkat. Salah satunya adalah dengan mengolahnya menjadi triacetin. Triacetin merupakan hasil reaksi antara gliserol dan asam asetat. Penggunaan katalisator padat berupa resin penukar ion Indion 225 Na dimaksudkan untuk mempermudah pemisahan hasil reaksi. Pembuatan triacetin pada penelitian ini dilakukan dalam reaktor batch, dengan kecepatan pengadukan 1000 rpm, suhu reaksi 333 K – 373 K, menggunakan katalisator padat ukuran diameter 0,085 cm, perbandingan pereaksi 7 gmol asam asetat/gmol gliserol, dan konsentrasi katalisator 3% berat asam asetat. Pengambilan sampel dilakukan setiap 15 menit sampai waktu reaksi 90 menit untuk dianalisis kadar asam bebasnya. Disamping itu, asam total, asam bebas, dan gliserol total pada saat awal reaksi ditentukan secara volumetri. Hasil percobaan menunjukkan konversi tertinggi diperoleh sebesar 41,7% pada suhu 373 K, dan laju reaksi merupakan langkah yang mengontrol. Pengaruh suhu terhadap konstanta kecepatan reaksi pada kisaran 333 K – 373 K dapat dinyatakan dengan persamaan berikut:
kr = 3,344 x 100000 exp (-7.955,56/T ) (1/detik)
Kata kunci: esterifikasi, asam asetat, gliserol, Indion 225 Na, triacetin, biodisel
Biodiesel is an environmentally friendly alternative fuel. The increase of biodiesel production is followed by the increase of the glycerol as by product. Therefore, conversion of glycerol into other products to increase its economic value should be done such as converting it to triacetin. Triacetin is a product from a reaction between glycerol and acetic acid. The use of solid catalysts such as ion exchange resin 225 Indion Na is an alternative method to ease product separation. Preparation of triacetin was conducted in a batch reactor with a stirring speed of 1000 rpm, at temperature of 333 K – 373 K, catalyst diameter of 0.085 cm, the reactant ratio of 7 gmol acetic acid / gmol glycerol, and catalyst concentration of 3% to weight of acetic acid. The sample was taken every 15 minutes in a reaction time of 90 minutes then was analized for free acid concentration. Total acid, free acid, and total glycerol were also determined by volumetric method at the early stage of reaction. The results showed that the highest conversion as high as 41.7% was achieved at 373 K. It was found that the reaction rate was the controlling step. The effect of temperature to rate of reaction constants in the temperature range of 333 K – 373 K can be expressed as follows:
kr = 3.344 x 100000 exp (-7,955.56/T ) (1/s)
Keywords: esterification, acetic acid, glycerol, Indion 225 Na, triacetin, biodiesel
oai:jurnal.ugm.ac.id:article/1898
2013-05-20T03:20:25Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1898
2013-05-20T03:20:25Z
Jurnal Rekayasa Proses
Vol 5, No 2 (2011); 40-44
Proses Produksi Biodiesel Berbasis Biji Karet
Soemargono,
Mulyadi, Edy
2011-05-20 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1898
Biodiesel tersusun dari berbagai macam ester asam lemak yang berasal dari minyak nabati. Lebih dari 30 macam tumbuhan Indonesia potensial menghasilkan minyak nabati. Salah satu minyak nabati diperoleh dari biji karet. Karenanya, pemanfaatan biji karet (Hevea Brasiliensis), sebagai sumber bahan baku biodiesel merupakan terobosan yang tepat untuk meningkatkan nilai tambah perkebunan karet. Penelitian ini dimaksudkan untuk menentukan pola pemungutan minyak biji karet secara maksimal dan mendapatkan kondisi proses produksi biodiesel yang memenuhi standar SNI dan ASTM. Proses produksi biodiesel dilakukan menggunakan prototip alat berkapasitas 20 liter/jam. Proses esterifikasi dijalankan pada suhu 105C, penambahan methanol 10% dan katalis asam, waktu 90 menit. Proses trans-esterifikasi dijalankan dalam reaktor alir osilasi dengan dosis katalis 1% berat minyak dan methanol sebanyak 15% berat minyak. Variabel yang dipelajari adalah suhu dan waktu proses. Produk biodiesel dimurnikan dengan sistem vakum. Dari hasil penelitian ini diperoleh rendemen kernel sebanyak 53% dari berat biji karet. Sedangkan minyak dalam kernel yang dapat dipungut maksimum 56% dari berat kernel. Karakteristik biodiesel sesuai dengan yang distandarisasikan, yaitu densitas 0,8565 g/ml, angka asam 0,49, angka iod 62,88, kadar ester 97,2%, flash point 178°C dan panas pembakaran 16183 J/g.
Kata Kunci: Biodiesel, minyak biji karet, reaktor osilasi, transesterifikasi
Biodiesel consists of various fatty acid esters which come from vegetable oil. More than 30 types of plants in Indonesia are potential to produce vegetable oils. One of the vegetable oils came from rubber seed. Therefore, utilization of rubber seed (Hevea Brasiliensis), as raw material for biodiesel was the precise breakthrough to add value to rubber plantation. This research aimed to determine the pattern of collection of oil of rubber seed maximally and to obtain the condition of production process of biodiesel fulfilling standard of SNI and ASTM. Biodiesel production was done in the prototype with a capacity of 20 liter/hour. The esterification process was conducted at 105°C using 10% methanol and acid catalyst for 90 minutes. Trans-esterification process was performed in an oscillating flow reactor with a catalyst dose of 1% oil weight and methanol as much as 15% oil weight. The effect of temperature and reaction time on product yield and quality were investigated. Purification of biodiesel was done in a vacuum system. Results from the present study showed that the yield of kernel through the process was up to 53% of the rubber seed weight. Meanwhile, the amount of oil could be extracted from the kernel was up to 56% of the kernel weight. The characteristic of biodiesel resulted from the process was in accord with that of the standard oil; density of 0.8565 g/ml, acid value 0.49, iodine value 62.88, ester fraction 97.2%, flash point 178C, heat of combustion 16,183 J/g.
Keywords: Biodiesel, rubber seed oil, oscillating reactor, transesterification
oai:jurnal.ugm.ac.id:article/1899
2013-05-20T03:20:25Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/1899
2013-05-20T03:20:25Z
Jurnal Rekayasa Proses
Vol 5, No 2 (2011); 45-49
Produksi Asam Lemak dari Dedak Melalui Proses Hidrolisis Enzimatis Secara In Situ
Hartati, Indah
Arifan, Fahmi
Yulianto, Mohammad Endy
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1899
Indonesia berpotensi sebagai penghasil asam lemak dari dedak padi yang jumlahnya melimpah. Dedak padi mengandung enzim lipase yang dapat mengkatalisis proses hidrolisis trigliserida pada dedak padi menjadi asam lemak. Penelitian ini bertujuan mengkaji proses hidrolisis trigliserida pada dedak padi dengan mengaktifkan enzim lipase. Studi produktivitas dilakukan dengan mengkaji pengaruh penambahan buffer phosphat terhadap pembentukan asam lemak. Studi produktivitas dilakukan dengan membandingkan perolehan asam lemak dengan atau tanpa penggunaan buffer pada proses hidrolisis. Parameter yang diteliti meliputi: volume buffer (0–25% terhadap volume air), rasio dedak-air (1:1–1:6 b/v), dan suhu reaksi (30–50°C). Hasil penelitian menunjukkan bahwa ion-ion pada larutan buffer mampu meningkatkan aktivitas dan stabilitas lipase. Penambahan buffer mampu meningkatkan perolehan asam lemak hingga 48%. Sementara perolehan asam lemak tertinggi dicapai pada hidrolisis dengan kondisi operasi volume buffer 5%, suhu reaksi 50°C dan rasio air dedak 1:5, dengan bilangan asamnya 2,63 mgek NaOH/g dedak
Kata Kunci: asam lemak, dedak padi, lipase, hidrolisis, enzimatis
Indonesia has potential to produce fatty acid from rice bran which is abundantly available as a side product of rice field activities. Rice bran contains lipase enzyme which is a catalyst for hydrolysis of triglycerides largely found in rice bran. The present work aimed to investigate the hydrolysis process of triglyceride from rice bran by activated lipase enzyme. Effect of the presence of phosphate compounds as buffer on fatty acid production was studied. The amount of fatty acid produced during hydrolysis with the use of buffer was compared to that without buffer. The parameters studied in the present work were volume of buffer (0% to 25% of water volume), rice bran-water ratio (1:1 to 1:6 w/v) and reaction temperature (30°C – 50°C). Experimental results showed that ions in the buffer solution could increase the activity and stability of lipase enzyme. The addition of buffer was found to increase fatty acid yield up to 48%. The highest fatty acid results ware obtained at the operation condition at which buffer volume of 5%, reaction temperature of 50°C and rice bran-water ratio of 1:5 where the acid number was 2.63 mgek NaOH/g rice bran.
Keywords: fatty acid, rice bran, lipase, hydrolysis, enzymatic
oai:jurnal.ugm.ac.id:article/1900
2013-05-20T03:20:25Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/1900
2013-05-20T03:20:25Z
Jurnal Rekayasa Proses
Vol 5, No 2 (2011); 50-55
Pembuatan Resin Fenol Formaldehid sebagai Prekursor untuk Preparasi Karbon Berpori: Pengaruh Turunan Phenol dan pH terhadap Karakteristik Resin dan Karbon
Mardyaningsih, Mamik
Rochmadi,
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1900
Phenol formaldehyde resin dapat dimodifikasi dengan menambahkan reaktan turunan phenol yaitu p-tert-butylphenol, hidroquinon, dan p-amino phenol untuk prekursor karbon berpori. Penelitian ini bertujuan untuk mempelajari pengaruh turunan phenol dan pH terhadap karakteristik resin dan karbon berpori. Polimerisasi dijalankan dalam labu leher tiga, yang dilengkapi dengan pengaduk magnet, jaket pemanas, termometer pada suasana basa, suhu 90°C selama 1-3 jam. Hasil resin didinginkan dan dinetralkan. Untuk proses curing, resin ditambah pTSA 5% berat serta diaduk sampai homogen. Resin yang dihasilkan kemudian dipanaskan pada suhu 150°C selama ± 10 menit. Proses karbonisasi dilakukan dengan pirolisis phenolic resin pada suhu 800°C selama 1 jam. Hasil penelitian menunjukkan bahwa kondisi optimum reaksi polimerisasi adalah pada pH 8. Produk resin dengan sifat fisis terbaik dimiliki oleh resin PFTBP yang mempunyai nilai rapat massa sebesar 1,18 g/cm3 dan nilai kekerasan sebesar 17,2 g/mm2. Karbon hasil pirolisis resin PF mempunyai surface area internal BET tinggi yaitu 836,7 m2/g dan bilangan iodin tinggi sebesar 862,3 mg/g.
Kata kunci: Phenol formaldehyde, resin, prekursor, karbon berpori.
Phenol formaldehyde resin can be modified by adding phenol derivates, such as tertiary butylphenol (TBP), hydroquinone (HQ), and p-amino phenol (AP). This research aimed at studying the effect of phenol derivates and pH on the resin characteristic and porous carbon. Polymerization was carried out in a three-neck flask, equipped with a magnetic stirrer, heating jacket and thermometer in a base condition, at 90°C and 1 to 3 hours reaction time. The resin was then cooled and neutralized. The curing process was carried out where resin was added by pTSA and then stirred to reach homogeneous condition. The resin was then heated at 150°C for ± 10 minutes. The carbonization process was conducted by pyrolizing the phenolic resin at 800°C for 1 hour. The result showed that the optimum condition of phenol formaldehyde reaction was at pH 8. Resin product that had optimum physical properties was PFTBP resin. It had a density of 1.18 g/cm3 and hardness value of 17.2 g/mm2. Among the phenolic resin materials produced, the PF carbon showed the highest product quality, indicated by high BET surface area of 836.7 m2/g and high iodine number of 862.3 mg/g.
Keywords: phenol formaldehyde, resin, precursor, porous carbon
oai:jurnal.ugm.ac.id:article/1901
2013-05-20T03:20:26Z
jrekpros:ART
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https://journal.ugm.ac.id/jrekpros/article/view/1901
2013-05-20T03:20:26Z
Jurnal Rekayasa Proses
Vol 5, No 2 (2011); 56-61
Bottom ash Limbah Batubara sebagai Media Filter yang Efektif pada Pengolahan Limbah Cair Tekstil
Rosyida, Ainur
2013-05-20 20:11:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/1901
Limbah cair tekstil mempunyai beban pencemaran yang tinggi sehingga dalam penanganannya perlu dipilih cara pengolahan dan media yang tepat agar hasil olahan memenuhi baku-mutu limbah. Salah satu tahap yang menentukan lamanya waktu pengolahan limbah adalah proses filtrasi. Kandungan zat organik, partikel padatan, dan logam berat dalam limbah dapat dikurangi dalam jumlah yang cukup besar dengan cara filtrasi, yang dapat mengurangi waktu dan beban pada proses selanjutnya (pengolahan biologi dengan lumpur aktif). Penelitian ini bertujuan untuk mendapatkan suatu bahan yang paling efektif untuk media filter pada pengolahan limbah cair industri tekstil. Pada penelitian ini dilakukan pembandingan kemampuan tiga jenis media filter yaitu karbon aktif, zeolit aktif dan limbah batubara (bottom ash). Sebelum dilakukan filtrasi, mula-mula limbah cair dilakukan stabilisasi, flotasi, koagulasi-sedimentasi agar partikel berukuran besar yang terkandung didalamnya terpisahkan. Limbah cair tersebut kemudian dialirkan dengan laju alir tertentu melalui kolom filtrasi yang terisi oleh media filter. Untuk mengetahui efektivitas media filter, diuji kandungan TSS, BOD, COD dan Cr limbah sebelum dan sesudah proses filtrasi. Hasil percobaan filtrasi dengan ketiga media filter menunjukkan bahwa filtrasi dengan menggunakan media bottom ash limbah batubara lebih baik dibanding dengan filtrasi dengan zeolit aktif dan karbon aktif. Filtrasi dengan bottom ash dapat menurunkan beban pencemaran dalam jumlah yang lebih besar, khususnya pada nilai TSS sebesar 32,5%, COD 54,1%, BOD 58,9% serta kandungan logam berat Cr 80,8%. Oleh sebab itu, bottom ash limbah batubara dapat digunakan sebagai media filter yang efektif dalam proses filtrasi limbah cair tekstil.
Kata kunci: limbah cair, industri tekstil, filtrasi, bottom ash, karbon aktif, zeolit aktif
Wastewater from textile industry contains very high contaminants. Therefore, a suitable treatment method is highly required to fulfill wastewater quality standard. Filtration is a step in wastewater treatment which affects duration of the whole process. By filtration, organic materials, solid particles and heavy metals can be significantly reduced. As a result, the load for biological process (activated sludge) decreases very much. The objective of this research is to obtain the most effective filtration medium for wastewater treatment from textile industry. Performance of three filter media (activated carbon, activated zeolite and coal bottom ash) were compared. The experiment was started by doing a preliminary process (stabilization, flotation, coagulation- sedimentation) to separate big size particles from wastewater before filtration. Then, the filtration medium was placed in a filtration column and a stream of wastewater was flown through the column at a certain flow rate. In order to better understand the effectiveness of medium, a sample of wastewater before and after filtration was measured for TSS, BOD, COD values and heavy metal (Cr) content. The experimental result showed that filtration using coal bottom ash was more effective than that using activated zeolite and activated carbon. The filtration was able to reduce TSS by 32,5%, COD by 54,1%, BOD by 58,9% and heavy metal (Cr) content 80,8%. Thus, coal bottom ash could be utilized as an effective filtration medium in the treatment of textile industry wastewater.
Keywords: wastewater, textile industry, filtration, bottom ash, activated carbon, activated zeolite
oai:jurnal.ugm.ac.id:article/2450
2013-11-04T01:50:57Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/2450
2013-11-04T01:50:57Z
Jurnal Rekayasa Proses
Vol 6, No 1 (2012); 1-6
Kinetika Pelarutan Silika Amorf dari Lumpur Panas Bumi Dieng
Riyanto, Nurdin
Sumardi, P
Perdana, Indra
2013-11-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/2450
Lumpur geotermal yang dihasilkan dari proses operasi Pembangkit Listrik Tenaga Panas Bumi Dieng mengandung silika amorf sebesar 50 %, yang sangat potensial untuk dijadikan sumber kebutuhan silika amorf untuk dunia industri. Penelitian ini bertujuan untuk mempelajari kinetika pelarutan silika amorf dari lumpur panas bumi dengan menvariasikan variabel – variabel yang mempengaruhinya. Pada penelitian ini, alkali-solubilization yang merupakan proses pelarutan silika dalam larutan NaOH dalam labu berpengaduk dipelajari dengan memvariasikan variabel suhu (50 – 90 °C), kecepatan pengadukan (150 – 450 rpm), perbandingan molar Na/Si (2 – 8), dan ukuran diameter padatan (0,0069 – 0,01975 cm). Hasil penelitian menunjukkan bahwa laju pelarutan silika amorf dari limbah geotermal meningkat dengan naiknya suhu dan kecepatan pengadukan. Namun, ukuran padatan dan perbandingan molar pereaksi tidak menunjukkan pengaruh yang berarti terhadap proses pelarutan.
Kata kunci: lumpur geotermal, silika amorf, alkali-solubilization, kinetika pelarutan
Dieng’s geothermal power plant generates not only energy but also wastes as sludge that contains around 50% silica in an amorphous state. The waste has a great potential to be used as a source of micro-amorphous silica synthesis to fulfill industrial needs. This research aimed to study the dissolution kinetics of amorphous silica. In the present work, the alkali – solubilization process by means of the dissolution of amorphous silica in an agitated flask was studied by varying process temperatures (50 – 90C), stirring speed (150 – 450 rpm), Na/Si molar ratio (2 – 3), and silica particle size (0,0069 – 0,01975 cm). Experimental results showed that the rate of geothermal silica dissolution increased with temperature and stirring speed. Meanwhile, Na/Si molar ratios and silica particle sizes showed no significant influence on the dissolution process. Calculation results indicated that the dissolution process involved a solid – liquid reaction that occured at the solid surface.
Keywords : geothermal sludge, amorphous silica, alkali-solubilization, dissolution kinetics
oai:jurnal.ugm.ac.id:article/2451
2013-11-04T01:50:57Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/2451
2013-11-04T01:50:57Z
Jurnal Rekayasa Proses
Vol 6, No 1 (2012); 7-13
Kajian Awal Laju Reaksi Fotosintesis untuk Penyerapan Gas CO2 Menggunakan Mikroalga Tetraselmis Chuii
Purba, Elida
Khairunisa, Ade Citra
2013-11-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/2451
Penelitian ini dilatarbelakangi oleh meningkatnya konsentrasi CO2 di udara akibat dari pembuangan proses industri dan pembakaran bahan bakar sehingga dapat menyebabkan global warming. Oleh karena itu dilakukan penelitian tentang pengurangan konsentrasi CO2 melalui reaksi fotosintesis menggunakan mikroalga Tetraselmis chuii. Tujuan penelitian ini untuk mendapatkan konstanta laju reaksi menggunakan Tetraselmis chuii. Penelitian dilakukan dengan menjenuhkan media kultur air laut terlebih dahulu dengan gas CO2, sehingga pengaruh difusi CO2 ke dalam media kultur dapat diabaikan. Kemudian mikroalga dimasukkan ke dalam fotobioreaktor dengan berbagai kondisi operasi. Kondisi operasi yang divariasikan adalah temperatur yakni, 28C, 30C, dan 35oC serta umpan gas CO2 sebesar 4, 9, dan 14% dengan rancangan percobaan acak lengkap. Hasil penelitian menunjukkan bahwa penyerapan tertinggi diperoleh pada suhu 30C dan 35oC untuk setiap konsentrasi masukan CO2.. Orde reaksi terhadap CO2 belum dapat disimpulkan karena tidak ada beda nyata faktor koreksi (R) pada setiap grafik untuk persamaan order reaksi 1, 2, dan 3.
Kata kunci : fotobioreaktor, penyerapan, Tetraselmis chuii, konstanta laju reaksi, konsentrasi CO2
The background of the present study was the facts that the increase of carbon dioxides concentration in the air due to industrial activities and fossil fuel combustion certainly leads to global warming. In order to reduce carbon dioxides concentration, photosynthesis reaction using Tetraselmis chuii was one of the potential methods to use. The present study aimed at determining the rate constant of reaction that used Tetraselmis chuii. The study was carried out by firstly saturating sea water as a culture media with carbon dioxide in order to reduce the influence of carbon dioxide diffusion through the media. Microalgae were then put inside the photo-bioreactor at different operating conditions. The operating variables investigated in the present work were temperature (28C, 30C and 35C) and inlet CO2 gas concentration (4, 9 and 14%) with a complete random experimental design. Experimental results showed that the highest absorption capacity was achieved at 30C and 35C for each inlet CO2 concentration. However, the order of reaction with respect to CO2 concentration could not have been determined since the correction factors (R) values obtained from graphical analysis of first, second and third order reactions were not significantly different.
Keywords : photo-bioreactor, absorption, Tetraselmis chuii, reaction rate constant, CO2 concentration
oai:jurnal.ugm.ac.id:article/2452
2013-11-04T01:50:58Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/2452
2013-11-04T01:50:58Z
Jurnal Rekayasa Proses
Vol 6, No 1 (2012); 14-19
Degradasi Substrat Volatile Solid pada Produksi Biogas dari Limbah Pembuatan Tahu dan Kotoran Sapi
Widarti,, Budi Nininga
Syamsiah, Siti
Mulyono, Panut
2013-11-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/2452
Limbah pembuatan tahu dan kotoran sapi merupakan bahan organik potensial untuk produksi biogas berdasarkan kandungan volatile solid. Penelitian ini bertujuan untuk mengetahui kandungan volatil solid optimal dari campuran limbah pembuatan tahu dan kotoran sapi dan untuk memperoleh parameter kinetika degradasi volatile solid untuk pembentukan biogas. Campuran dengan komposisi tertentu dimasukkan ke dalam digester. Untuk mencapai kondisi anaerob, gas N2 dialirkan ke dalam digester, kemudian digester ditutup rapat. Campuran diinkubasi di dalam water bath pada suhu 35oC selama 56 hari. Volume biogas dan pH diukur setiap hari. Metana, volatile fatty acid dan volatile solid dianalisis setiap 7 hari. Karbohidrat, protein dan lemak dalam slurry dianalisis tiga kali selama proses produksi biogas. Hasil penelitian menunjukkan digester dengan kandungan volatile solid 12% menghasilkan yield biogas tertinggi yaitu sebesar 89,522 mL/g volatile solid dengan konsentrasi metana tertinggi 14,68%. Model kinetika degradasi volatile solid dapat didekati dengan model first order reaction.
Kata kunci: Limbah pembuatan tahu, kotoran sapi, volatile solid, biogas
Waste from tofu production and cow dung are potential organic materials for biogas production based on the content of volatile solid. This study aims to determine the optimal content of volatile solid in a mixture of tofu production waste-cow dung and to obtain the kinetic parameters of the degradation of volatile solid to form biogas. A mixture at certain composition is put into digester. To obtain anaerobic condition, N2 gas is flown into the digester, and then the digester is sealed. The mixture is incubated in a water bath at a temperature of 35oC for 56 days. Biogas volume and pH are measured every day. Methane, volatile fatty acids and volatile solid are analyzed every 7 days. Carbohydrates, proteins and fats in the slurry are analyzed three times during the production of biogas. The results showed that digester with 12% volatile solid produces the highest biogas yield of 89.522 mL/g volatile solid, with the highest methane concentration 14.68%. Kinetics model of degradation of volatile solid can be approached by a first order reaction model.
Keyword: waste of tofu production, cow dung, volatile solid, biogas
oai:jurnal.ugm.ac.id:article/2453
2013-11-04T01:50:58Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/2453
2013-11-04T01:50:58Z
Jurnal Rekayasa Proses
Vol 6, No 1 (2012); 20-25
Studi Proses Pembuatan Biodiesel dari Minyak Kelapa (Coconut Oil) dengan Bantuan Gelombang Ultrasonik
Putri, Sri Kembaryanti
Supranto,
Sudiyo, Rahman
2013-11-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/2453
Biodisel dapat dibuat melalui proses metanolisis berbagai minyak nabati seperti minyak kelapa, minyak kelapa sawit, minyak kedelai dan lain-lain. Minyak kelapa memiliki potensi besar untuk digunakan sebagai bahan baku dalam pembuatan biodisel karena ketersediaannya yang berlimpah. Gelombang ultrasonik dapat digunakan untuk meningkatkan konversi reaksi dan mempercepat laju reaksi. Tujuan penelitian ini adalah untuk mempelajari pengaruh penggunaan gelombang ultrasonik dalam proses transesterifikasi minyak kelapa, perbandingan pereaksi, konsentrasi katalisator dan aktivasi metanol terhadap konversi reaksi. Katalisator natrium hidroksida dengan berat tertentu dilarutkan di dalam metanol dalam volum tertentu. Setelah terlarut sempurna bersamaan dengan minyak kelapa dimasukkan ke dalam reaktor dan reaksi dijalankan. Sampel diambil setiap interval 10 menit untuk dianalisis kandungan asam lemaknya. Reaksi dihentikan setelah mencapai waktu 60 menit. Setelah itu, biodisel yang terbentuk dipisahkan dari gliserol dan dimurnikan. Hasil percobaan menunjukkan bahwa transesterifikasi minyak kelapa dapat dipacu dengan bantuan gelombang ultrasonik. Konversi reaksi yang dicapai empat kali lebih besar (85,66%) dibandingkan dengan konversi pada proses konvensional (20,15%). Proses dilakukan pada kondisi operasi yang sama; perbandingan pereaksi 5 mgek metanol/mgek minyak, 1% berat katalisator, dan suhu awal reaksi 60°C. Hasil penelitian menunjukkan semakin tinggi perbandingan ekivalen metanol-minyak, semakin tinggi konversi reaksi yang dicapai.
Kata kunci: biodisel, minyak kelapa, transesterifikasi, gelombang ultrasonik, tetapan laju reaksi
Biodiesel is produced by methanolysis of various vegetable oils such as coconut oil, palm oil, seed oil, soybean oil, etc. Coconut oil has the potential as a raw material for making biodiesel due its abundant availability. The use of the ultrasonic waves can increase conversion and reaction rate. The objective of this study was to study the effect of the use of ultrasonic waves on the transesterification of coconut oil, the ratio of reactants, catalyst concentration, and activation of methanol on the reaction conversion. Sodium hydroxide catalyst with a specific weight was dissolved in methanol with a certain volume. After dissolvtion was completed, the reactants including coconut oil with a certain volume were put into the reactor, and reaction was then started. Samples were taken every 10 minute intervals for analysis of fatty acids. The reaction was stopped after 60 minutes. Furthermore, biodiesel was separated from glycerol and purified. Experimental results showed that transesterification of coconut oil could be improved with the help of ultrasonic waves. The obtained conversion was 4 times higher (85,66%) than the conversions generated in the conventional process (20,15%) The process was done in the same condition which was the ratio of reactants of 5 mgek methanol / mgek oil, catalyst 1% by weight oil and the initial reaction temperature of 60C. The greater the ratio of methanol-oil equivalent, the higher reaction conversion is.
Keywords: biodiesel, coconut oil, transesterification, ultrasonic wave, reaction rate constant
oai:jurnal.ugm.ac.id:article/2454
2013-11-04T01:50:58Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/2454
2013-11-04T01:50:58Z
Jurnal Rekayasa Proses
Vol 6, No 1 (2012); 26-29
Pembuatan Zat Warna Alami dalam Bentuk Serbuk untuk Mendukung Industri Batik di Indonesia
Paryanto,
Purwanto, Agus
Kwartiningsih, Endang
Mastuti, Endang
2013-11-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/2454
Zat warna sintetis sangat praktis digunakan serta dapat menimbulkan warna yang mencolok pada produk. Namun limbah buangan zat warna sintetis dapat mencemari lingkungan. Saat ini zat warna alami mulai digunakan kembali. Untuk memudahkan pemakaian, zat warna alami berbentuk cair dikeringkan menjadi serbuk. Ekstrak zat warna alami dari biji kesumba dalam penelitian ini dikeringkan menggunakan spray dryer sehingga terbentuk serbuk. Zat warna kesumba diekstraksi dengan pelarut larutan NaOH dan Ca(OH)2. Pengeringan dilakukan dengan laju umpan rata – rata 0,13 ml/detik dengan suhu umpan 70°C dan suhu pengering 120°C. Pelarut NaOH memberikan hasil yang lebih baik dibanding pelarut Ca(OH)2. Kondisi yang relatif baik dicapai pada penggunaan pelarut NaOH 0,4 M, suhu 90C dan waktu 180 men. Serbuk yang dihasilkan 19,6 g/L larutan ekstrak.
Kata Kunci : zat warna alam, serbuk, biji kesumba, pengering sembur, batik.
Synthetic dyes are very practical to use and can lead to a striking color on the products. However, synthetic dye effluent may pollute the environment. For this reason, currently natural dyes have been used again for coloring. In order to ease the use of natural dyes, the liquid form of the dyes is dried into powder. In the present study, natural dyes extracted from kesumba seeds were dried using a spray dryer to form a powder. The Kesumba dye was extracted in an alkaline solutions of NaOH and Ca(OH)2. Drying was carried out with a feed having an average rate of 0.13 ml/sec at a temperature of 70°C. Meanwhile, dryer temperature was 120C. Experimental results showed that extraction using NaOH solution offered better results than that using Ca(OH)2 solution. The extraction using NaOH solution was optimum at NaOH concentration of 0.4 M, temperature of 90C and duration of 180 min. With this condition, the resulting powder was 19.6 g/L extract solution.
Keywords : natural dye, powder, kesumba seed, spray dryer, batik.
oai:jurnal.ugm.ac.id:article/4693
2014-06-04T02:42:53Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4693
2014-06-04T02:42:53Z
Jurnal Rekayasa Proses
Vol 6, No 2 (2012); 30-36
Studi Simulasi pada Unit Reformer Primer di PT Pupuk Sriwidjaya Palembang
Abdurrakhman, Sigit
Sutijan,
Hidayat, Muslikhin
2014-06-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4693
Pabrik amonia merupakan salah satu pabrik yang terdapat di industri pupuk. Unit Reformer Primer merupakan salah satu alat di pabrik amonia yang merupakan tempat terjadinya reaksi katalitik antara steam dengan metana dikenal dengan proses steam methane reforming. Bahan baku utama adalah steam (H2O) dan gas alam dengan kandungan utama metana (CH4). Penelitian ini membuat model proses unit Reformer Primer untuk menghitung profil temperatur, tekanan dan komposisi untuk kondisi operasi steady state dengan berdasarkan kondisi operasi di pabrik Amonia Pusri 3 PT Pupuk Sriwidjaya Palembang.
Asumsi yang digunakan adalah plug flow baik pada sisi furnace maupun pada sisi reaktor katalitik dan kondisi steady state. Untuk menyelesaikan persamaan diferensial ordiner yang digunakan pada penelitian ini dipakai metode Runge Kutta dengan program SciLab sehingga didapat profil konversi dan temperatur di Reformer Primer. Variabel yang mempengaruhi dalam reaksi di Reformer Primer adalah temperatur, tekanan, dan komposisi.
Hasil simulasi jika dibandingkan dengan data operasional pabrik menunjukkan ralat rerata 3,94 %. Jika model tersebut digunakan pada berbagai kondisi operasi menghasilkan ralat rerata 7,01 %.
Kata kunci: reformer primer, metana, steam, amonia
Ammonia plant is the main part of fertilizer industry. Primary reformer is an unit operation where catalytic reaction between steam and methane take place, or it is known as steam methane reforming. The main raw material is steam (H2O) and natural gas with major content of methane (CH4). The objective of this research was to develop primary reformer unit process model to calculate temperature, pressure and composition profiles for steady state operation according to operating condition on Ammonia III plant in PT Pupuk Sriwidjaya Palembang.
The assumption used was plug flow model both on the furnace side and on the catalytic reactor side for steady state conditions. The ordinary differential equations were solved using Runge Kutta method with Scilab software to get the conversion, pressure and temperature profiles on primary reformer. Variabels evaluated were temperature, pressure, and composition.
The simulation result showed that an average error of 3.94 % compared to the operational plant data. For various operating conditions this simulation showed an average error of 7.01 %.
Keyword: primary reformer, methane, steam, ammonia
oai:jurnal.ugm.ac.id:article/4694
2014-06-04T02:43:12Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4694
2014-06-04T02:43:12Z
Jurnal Rekayasa Proses
Vol 6, No 2 (2012); 37-42
Kinetika Reaksi Polimerisasi Urea-Asetaldehid dalam Proses Enkapsulasi Urea
Purnamasari, Indah
Rochmadi,
Sulistyo, Hary
2014-06-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4694
Untuk meningkatkan efektivitas penggunaan urea dan mengurangi pencemaran lingkungan, perlu dilakukan enkapsulasi urea sehingga pelepasan urea dalam air dapat dikontrol. Dinding kapsul terbentuk langsung di permukaan partikel urea yang disebut in situ polimerisasi. Penelitian ini bertujuan untuk mempelajari kinetika reaksi polimerisasi urea dan asetaldehid dalam proses enkapsulasi urea.
Urea dan asetaldehid dengan perbandingan 1:1,2 mol/mol dimasukkan ke dalam erlenmeyer yang dilengkapi dengan termometer dan pendingin. Reaksi dijalankan di dalam erlenmeyer selama 2 jam dan contoh diambil setiap 20 menit untuk dianalisis asetaldehid sisa dengan metode sodium sulfit dan ukuran butiran diukur dengan mikroskop optik dan menggunakan software image pro. Variabel yang dipelajari adalah suhu reaksi (5-15°C), ukuran butir urea (14, 18, dan 25 mesh), dan pH (2, 3, 4). Konstanta kecepatan reaksi dan koefisien difusivitas ditentukan dengan optimasi antara model dengan data penelitian.
Hasil penelitian menunjukkan bahwa semakin tinggi suhu dan ukuran butir, semakin tinggi konversi yang dihasilkan. Semakin rendah pH (semakin asam) memberikan konversi yang semakin tinggi akan tetapi butiran hasil sedikit mengembang dan lengket. Model kinetika reaksi yang diajukan sesuai dengan data pengamatan. Reaksi adisi berlangsung lebih cepat dibandingkan dengan reaksi kondensasi. Kondisi reaksi yang cukup baik terjadi pada suhu reaksi 15°C, pH 4, ukuran butir 14 mesh dan waktu 120 menit dengan konversi sebesar 63,38%. Pada kondisi ini, produk polimer yang dihasilkan lebih keras dibandingkan dengan kondisi yang lainnya.
Kata kunci: enkapsulasi, urea-asetaldehid, polimerisasi, pelepasan terkontrol
The function of urea encapsulation is to control its release in water, thus increasing effectiveness of using urea and reducing environmental pollution. Microcapsule shell is formed directly on the surface of urea particles called in-situ polymerization. This research aimed to study the kinetics of the polymerization reaction of urea and acetaldehyde in the urea encapsulation process.
Urea and acetaldehyde in the ratio of 1:1.2 mol/mol were placed in an erlenmeyer equipped with a thermometer and cooler. The reaction was run for 2 hours in erlenmeyer and sample was taken every 20 minutes. The amount of remaining acetaldehyde was determined by sodium sulfite method and grain size was measured by optical microscope and image pro software. Variables investigated were reaction temperatures (5 - 15°C), particle sizes (14, 18, and 25 mesh), and pH (2 - 4). Reaction rate and diffusivity constants were determined through fitting the experimental data and proposed model.
The results showed that the higher temperature and grain size, the higher conversion was. Lower pH (more acid) provides higher conversion but urea particle was seen slightly swelling during the reaction, and also slightly sticky. Addition reaction was much faster than condensation reaction. The proposed reaction kinetics model fitted reasonably well to the experimental data. The process was best conducted at 15°C, 14 mesh, pH 4 and 120 minutes time of reaction which result in 63.38% conversion. Polymer product of urea-acetaldehyde obtained at this condition was slightly harder than that at other conditions.
Keywords: encapsulation, urea-acetaldehyde, polymerization, controlled release
oai:jurnal.ugm.ac.id:article/4695
2014-06-04T02:43:22Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4695
2014-06-04T02:43:22Z
Jurnal Rekayasa Proses
Vol 6, No 2 (2012); 43-50
Studi Tekno-Ekonomi Pemurnian Biogas dari Limbah Domestik
Wahyu P, Akhwari
Fahrurrozi, Moh
Hidayat, Muslikhin
2014-06-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4695
Pemurnian biogas untuk meningkatkan nilai kalor pembakaran dan mencegah korosi. Biogas yang berkomposisi 95% CH4 dapat dimanfaatkan sebagai pengganti gas alam kualitas pipeline. Penelitian ini bertujuan mempelajari kelayakan secara teknis dan ekonomi metode pemurnian biogas, nilai production cost, kapasitas scale-up.
Penelitian ini menggunakan data sekunder dari pilot plant Biogas Pasar Induk Buah dan Sayuran Gemah Ripah, Gamping, Sleman. Penelitian menghitung nilai production cost dan kapasitas scale-up untuk tiap metode pemurnian biogas. Sensitivity analysis yang dilakukan pada perubahan komposisi gas CH4 terhadap nilai perbandingan laju solven terhadap laju biogas pada menara absorber dan perubahan harga limbah serta perubahan finances.
Secara ekonomi pemurnian biogas paling murah menggunakan water scrubber dengan kapasitas minimum 100 ton limbah domestik/hari. Nilai production cost yang lebih rendah dari harga gas alam kualitas pipeline berkisar antara 6-10 US$/MMBtu. Sensitivity analysis menghasilkan perubahan nilai L/G berkisar 0,005-0,025; variasi harga limbah dari penurunan sampai dengan kenaikan 100% dan perubahan finances 0-15 %, masing-masing memberikan perubahan production cost antara 3-8 US$/MMBtu dan 2-14 US$/MMBtu.
Kata kunci : pemurnian biogas, limbah domestik, tekno-ekonomi, biometan
Biogas purification can increase the caloric value of combustion and prevent corrosion. Biogas with 95% of methane is similar to pipeline quality natural gas. The objective of this research was to study technical and economical feasibility of biogas purification and also to estimate gas production cost and scale up capacities.
This research used the secondary data from pilot plant of Biogas of Pasar Induk Buah dan Sayuran Gemah Ripah, Gamping, Sleman, Yogyakarta. This research was to obtain the production cost and scale up capacities for each biogas purification method. The sensitivity analysis was conducted to study the influence of gas composition ranged at 30-70% CH4 toward the flow of absorbent to gas ratio, the price of waste changed from decreasing 100% up to increasing 100% and the finance changed ranged at 0-15% to the change of production cost.
The result showed that water scrubber was the cheapest method for scrubbing impurities. The production cost of scale up capacities compared to the price of pipeline quality natural gas which ranged at 6-10 US$/MMBtu. The minimum capacity of economical biogas purification methods was 100 tons waste/day. The influence of gas composition ranged at 30-70% of CH4 produced the L/G value change in the absorber column ranged at 0,005-0,025; the influence of waste price from decreasing and up to increasing 100% and finances from 0-15% produced the production cost change ranged at 3-8 US$/MMBtu and 2-14 US$/MMBtu respectively.
Keywords: biogas purification, domestic waste, techno-economic, bio-methane.
oai:jurnal.ugm.ac.id:article/4696
2014-06-05T01:45:31Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4696
2014-06-05T01:45:31Z
Jurnal Rekayasa Proses
Vol 6, No 2 (2012); 51-58
Life Cycle Assessment Pabrik Semen PT Holcim Indonesia Tbk. Pabrik Cilacap: Komparasi antara Bahan Bakar Batubara dengan Biomassa
Harjanto, Taufan Ratri
Fahrurrozi, Moh
Bendiyasa, I Made
2014-06-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4696
PT. Holcim Indonesia Tbk. Pabrik Cilacap dengan kapasitas produksi 2,6 juta ton/tahun telah menggunakan sekam padi sebagai energi alternatif biomassa. Penggantian batubara dengan biomassa akan menimbulkan emisi dan dampak ke lingkungan. Penelitian ini bertujuan untuk mengevaluasi dampak lingkungan penggunaan batubara dan biomassa dengan menggunakan metode Life Cycle Assessment (LCA).
Pendekatan cradle to gate digunakan untuk mengevaluasi 4 skenario penggunaan bahan bakar: (1) 100% batubara, (2) campuran 90% batubara dan 10% biomassa, (3) campuran 50% batubara dan 50% biomassa, (4) 100% biomassa, dengan basis 1000 kg produk semen. Langkah-langkah evaluasi mengacu pada ISO 14040 tahun 2006 yang terdiri dari: (1) pendefinisian tujuan dan ruang lingkup, (2) analisis inventori, (3) analisis/penakaran dampak, (4) interpretasi.
Hasil analisis kontribusi dampak terhadap lingkungan dengan skenario 1, 2, 3, dan 4 diperoleh nilai kontribusi total berturut-turut 2,78 x10-1 Pt, 2,24 x10-1Pt, 1,57 x10-1Pt, dan 8,50 x10-2 Pt. Kategori dampak global warming, respiratory inorganic dan resources merupakan kontributor terbesar dari total dampak terhadap lingkungan. Analisis perbaikan dan rekomendasi mengurangi dampak yang terjadi yaitu mengganti angkutan truck pasir silika dengan kereta api, bahan bakar biomassa menggunakan miscanthus giganteus dan melakukan penghijauan.
Kata kunci : PT Holcim Indonesia Tbk. Pabrik Cilacap, Life Cycle Assessment, Komparasi batubara dengan biomassa
PT. Holcim Indonesia Tbk. Cilacap having capacity of 2.6 million ton/year uses rice husk as alternative fuels. The utilization of the rice husk will effect the environment. The aim of the study is to evaluate the effects of biomass utilization to environment using life cycle assessment (LCA) method.
The “cradle to gate” approach was used to evaluate four scenarios of different fuel combinations: (1) 100% coal, (2) mixed fuel of 90% coal and 10% biomass, (3) mixed fuel of 50% coal and 50% biomass, (4) 100% biomass as primary fuels in the kiln for 1000 kg cement. Evaluation of environment impact related to each scenario was using ISO 14040 (2006) that consists of: (1) goal definition and scoping, (2) inventory analysis, (3) impact assessment, and (4) interpretation.
Results showed by contribution analysis, the scenario 1, 2, 3, and 4, give 2.78 x10-1 Pt, 2.24 x10-1Pt, 1.57 x10-1Pt, and 8.50 x10-2 Pt respectively. It was also found that the global warming, respiratory inorganic and resources give significant impacts to the environment. It is suggested to replace silica tranportation using train, to utilize miscanthus giganteus and to grow plants or reforestry.
Keywords: PT Holcim Indonesia Tbk Cilacap Plant, Life Cycle Assessment, Comparative Coal with Biomass.
oai:jurnal.ugm.ac.id:article/4697
2014-06-04T02:43:55Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4697
2014-06-04T02:43:55Z
Jurnal Rekayasa Proses
Vol 6, No 2 (2012); 59-65
Karakterisasi dan Laju Pembakaran Biobriket Campuran Sampah Organik dan Bungkil Jarak (Jatropha curcas L.)
Kurniawan, Eddy
Sediawan, Wahyudi Budi
Hidayat, Muslikhin
2014-06-04 20:12:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4697
Potensi limbah biomassa dan bungkil jarak pagar cukup besar dan saat ini belum termanfaatkan. Kedua bahan tersebut dapat diolah menjadi bio-arang melalui proses pirolisis. Bio-arang dapat digunakan sebagai bahan bakar. Tar dan tepung tapioka digunakan sebagai perekat dalam pembuatan briket arang.
Pada penelitian ini digunakan briket arang dengan fraksi massa bungkil jarak pagar 0, 25, 50, 75 dan 100%. Percobaan diawali dengan pembuatan arang, penghalusan arang dan pengayakan ukuran 35 mesh, pencampuran bahan baku dengan pelbagai komposisi dengan penambahan perekat (tapioka atau tar) kemudian ditekan dengan tekanan 1 kg/cm2. Selanjutnya, briket dianalisis kuat tekan, kadar air, kadar bahan mudah menguap, kadar abu, karbon terikat dan nilai kalor. Pembakaran briket dilakukan untuk mempelajari laju pembakaran dengan model matematis.
Hasil analisis model matematis menunjukkan bahwa laju pembakaran briket pada komposisi bungkil jarak 75% dengan perekat tar, lebih cepat. Briket yang menggunakan perekat tar memberikan asap pada saat dibakar, sedang penggunaan perekat tapioka tidak manghasilkan asap. Model matematis yang diajukan dapat menggambarkan laju pembakaran briket. Parameter kinetik dan laju pembakaran dapat diperoleh dari model yang diajukan.
Kata kunci: briket, bahan perekat, laju pembakaran, parameter kinetik
The potential of biomass municipal waste and jatropha cakes is abundant, but has not been utilized. These materials can be converted into biobriquette via pyrolisis, which can be used as alternative fuel. Tar and tapioca adhesive were applied for the binder.
In this study, briquettes with the mass fraction of jatropha cakes of 0, 25, 50, 75 and 100% were used. Research was done by performing carbonization, screening (35 mesh), mixing raw materials (municipal waste, jatropha cakes, tapioca adhesive and tar adhesive) and pressing at 1 kg/cm². Briquettes were then analyzed for compressive strengh, heating value, the moisture content, volatile matter, ash and fixed carbon. The combustion of the briquette was undertaken to study the rate of combustion.
Mathematical model showed that the rate of combustion of the briquette with composition of municipal waste and jatropha oil cakes (25% : 75%) with adhesive tar was faster. Briquettes with adhesive tar produce smoke when burned, while briquettes with tapioca adhesive is smoke-free. Therefore it is more preferable. The proposed mathematical model describes the rate of combustion of the briquette well. The kinetic parameter of the rate of combustion were also obtained.
Keywords: Briquette, adhesive materials, rate of combustion, kinetics parameter.
oai:jurnal.ugm.ac.id:article/4939
2014-08-16T05:15:31Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4939
2014-08-16T05:15:31Z
Jurnal Rekayasa Proses
Vol 7, No 1 (2013); 1-5
Coating in Primary Reformer’s Radiant Section
Nugraha, Baskara Aji
2014-07-14 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4939
Kaltim Parna Industri (KPI) mengalami masalah pada coil heat exchanger pada bagian konveksi primary reformer yang memanfaatkan panas flue gas yaitu berupa fouling pada bagian luar tube coil exchanger (finned tube). Pada awalnya belum diketahui sumber penyebab fouling, namun dari hasil analisis laboratorium diketahui bahwa komponen penyusun fouling sama dengan komponen firebrick (batu tahan api). Oleh karena itu diambil kesimpulan bahwa penyebab fouling adalah firebrick yang tererosi lalu terbawa aliran flue gas.
Salah satu cara untuk menghilangkan sumber fouling adalah dengan melakukan coating pada ruang bakar yang terdapat firebrick di dalamnya. Coating dilakukan dengan menggunakan cat khusus yang tahan suhu tinggi yang mampu menahan permukaan fire brick dari erosi.
Kata kunci: seksi konveksi, fouling, pelapisan, firebrick, reformer
Kaltim Parna Industri, (KPI), experienced severe fouling on the flue gas side of the coil heat exchangers. This happened on the outer tube side, which some were finned tubes. Although the cause had not clearly been identified, laboratory analysis indicated that the fouling had similar composition with the firebrick. Therefore, preliminary assumption of what causes the problem was firebrick erosion that was carried away by flue gas flow.
In order to completely eliminate fouling source and hopefully to reduce cleaning frequency, we planned to coat combustion chamber with special high temperature resistance coating.The result was promising that the material was stable against high temperature and even further helped the operation.
Keywords: convection section, fouling, coating, firebrick, reformer
oai:jurnal.ugm.ac.id:article/4940
2014-08-16T05:15:46Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4940
2014-08-16T05:15:46Z
Jurnal Rekayasa Proses
Vol 7, No 1 (2013); 6-13
Aplikasi Analisis Pinch untuk Menurunkan Konsumsi Steam di Bagian Process House Pabrik Gula
Daniyanto,
2014-07-14 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4940
Salah satu indikator efisiensi energi pabrik gula adalah Steam on Cane (SOC). SOC menunjukkan pemakaian steam tiap berat tebu. Semakin kecil SOC, efisiensi energi pabrik gula semakin baik. Sumber bahan bakar utama pabrik gula adalah bagasse. Bagasse merupakan ampas hasil ekstraksi tebu. Pabrik gula yang efisien akan memiliki SOC kurang dari 50%. Nilai SOC lebih dari 50% menyebabkan pabrik gula harus menggunakan tambahan bahan bakar selain bagasse. Jika SOC kurang dari 40 % berat tebu maka pabrik gula bisa melakukan kogenerasi dan menghasilkan listrik untuk dijual. Penelitian ini bertujuan untuk menurunkan SOC dengan cara menurunkan konsumsi steam di process house melalui inovasi konfigurasi proses dengan analisis pinch.
Hasil penelitian menunjukkan bahwa analisis pinch bisa digunakan untuk menurunkan konsumsi uap di pabrik gula. Penggunaan uap evaporator dari unit multiple effect evaporator akan mampu menurunkan konsumsi uap bagian process house. Perubahan konfigurasi proses memberikan penurunan SOC sebesar 8,8% dari kondisi semula. Uap evaporator 2 bisa digunakan untuk sumber panas pemanas 1 dan pemanas 2, uap evaporator 1 untuk sumber pemanas vacuum pan dan exhaust steam hanya digunakan untuk pemanas 1 dan vacuum pan.
Kata kunci: efisiensi energi, steam on cane, kogenerasi, konfigurasi proses, analisis pinch.
The energy efficiency of sugar factory can be indicated by variable steam on cane (SOC). SOC is defined as weight of steam consumption per weight of crushed cane. The smaller the SOC, the energy efficiency of sugar mills is better. The main source of fuel in sugar mill is bagasse. The sugar factory will be efficient if SOC is less than 50%. If SOC value is more than 50%, it will cause additional fuel other than bagasse. If SOC is less than 40%, the cane sugar mill can do cogeneration and produce electricity for sale. This study aims to reduce SOC by reducing steam consumption in the process house through configuration process innovation with pinch analysis.
The results showed that pinch analysis could be used to reduce steam consumption in sugar mill. Utilization of steam from evaporator could reduce steam consumption in the process house. The change in process configuration could provide SOC decrease by 8.8% from its former state. Steam produced by evaporator 2 could be used as heat source for heater 1 and heater 2, meanwhile steam produced by evaporator 1 as a heat source for vacuum pan. Exhaust steam could be used only for heater 3 and vacuum pan.
Keywords: energy efficiency, steam on cane, cogeneration, process configuration, pinch analysis.
oai:jurnal.ugm.ac.id:article/4941
2014-08-16T05:15:57Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4941
2014-08-16T05:15:57Z
Jurnal Rekayasa Proses
Vol 7, No 1 (2013); 14-18
Modifikasi Mekanisme Koufopanos pada Kinetika Reaksi Pirolisis Ampas Tebu (Bagasse)
Erawati, Emi
Sediawan, Wahyudi Budi
Mulyono, Panut
2014-07-14 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4941
Ampas tebu merupakan produk samping dari ekstraksi gula. Ampas tebu yang dihasilkan di pabrik gula sekitar 13% dari tebu yang digiling. Tujuan penelitian ini adalah menentukan energi aktivasi dan pre-exponential factor pada persamaan kinetika reaksi pirolisis ampas tebu.
Pirolisis dilakukan dalam reaktor yang terbuat dari pipa besi jenis 5737 dengan diameter 7,62 cm dan panjang 37 cm. Reaktor ini dimasukkan ke dalam furnace yang berdiameter 15,24 cm dan panjang 40 cm. Seratus lima puluh gram ampas tebu dimasukkan ke dalam reaktor tanpa kehadiran oksigen pada tekanan atmosferis. Pirolisis dilakukan pada berbagai ukuran bahan, yakni: (-20+25), (-25+30), (-30+35), (-35+40), -40 mesh dengan kecepatan pemanasan bervariasi 100, 105, 115, dan 120 volt.
Modifikasi mekanisme Koufopanos terdiri dari 4 tahap reaksi, yaitu: bahan baku bereaksi menjadi intermediate dan intermediate bereaksi menjadi gas, cair, dan padatan. Berdasarkan data eksperimen, diperoleh data parameter kinetika reaksi overall rata-rata E1, E2, E3, dan E4 masing-masing sebesar 8.750,48; 2.350,7;11.080,97; dan 6.625,49 J/mol, dengan pre-exponential factor yang bersesuaian A1, A2, A3, dan A4 sebesar 9,20x10-3; 2,13x10-2; 1,67; dan 2,31 detik pada variasi diameter partikel dan kecepatan pemanasan.
Kata kunci: energi aktivasi, ampas tebu, mekanisme Koufopanos, pirolisis, kinetik.
Bagasse is a side product of sugar cane extraction. A sugar factory produces bagasse of about 13% from the total cane milled. According to the data from BPPS (1999-2007) the total bagasse produced is about two million tons. The aim of this study is to determine the value of activation energy and pre-exponential factor of pyrolysis kinetics of sugar cane bagasse. Pyrolysis had been carried out in a reactor made of steel pipe type 5737 with a dimension of 7.62 cm dia and of 37 cm long.The reactor was inserted into a furnace with a diameter of 15.24 cm and a length of 40 cm. One hundred and fifty grams of bagasse had been added into the reactor without the presence of oxygen at atmospheric pressure. Pyrolysis had been carried out at the particle size of (-20+25) mesh, (-25+30) mesh, (-30+35) mesh, (-35+40) mesh, and -40 mesh and heating rate of 100, 105, 115, and 120 volt.
Modification of Koufopanos mechanism described four reaction steps, namely the reaction to produce intermediate product and further reaction in which intermediate product converted into gas, bio-oil, and char product was the most appropriate reaction model. From the modified model the activation energy E1, E2, E3, and E4 was 8,750.48; 2,350.7 ; 11,080.97 ; and 6,625.49 J/mol, respectively, while the pre-exponential factor A1, A2, A3, and A4 was 9.20x10-3 ; 2.13x10-2 ; 1.67 ; and 2.31 second, respectively for various size particles and heating rates.
Keywords: activation energy, bagasse, Koufopanos mechanism, pyrolysis, kinetic.
oai:jurnal.ugm.ac.id:article/4942
2014-08-16T05:16:10Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4942
2014-08-16T05:16:10Z
Jurnal Rekayasa Proses
Vol 7, No 1 (2013); 19-24
Studi Pemanfaatan Condensate Outlet Steam Trap Sebagai Air Umpan Boiler di Pabrik Amoniak Pusri-IB
Widyawan, Alfa
Fachlevie, Ferlyn
2014-07-14 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4942
Sebagai produsen amoniak dan urea, PT. Pusri memerlukan steam dalam jumlah yang relatif besar. Steam di pabrik amoniak digunakan sebagai bahan baku pabrik amoniak, sebagai pemanas dan penggerak turbin. Tekanan steam yang digunakan di pabrik Amoniak P-IB bervariasi, dari 3,5 kg/cm2gauge sampai 123 kg/cm2gauge. Distribusi steam yang dialirkan melalui pipa menuju peralatan mengakibatkan kehilangan panas ke lingkungan. Hal ini menyebabkan terbentuknya steam condensate di sepanjang aliran pipa. Selama ini steam condensate yang keluar dari pipa melalui steam trap langsung dibuang ke sewer. Studi ini dimaksudkan untuk menghitung laju kondensasi steam dan kelayakan ekonomi untuk memanfaatkan steam condensate tersebut sebagai air umpan boiler di pabrik Amoniak P-IB.
Perpindahan panas di pipa dihitung menggunakan prinsip perpindahan panas konduksi, konveksi dan radiasi. Perhitungan laju kondensasi steam dilakukan dengan variasi tekanan steam 123, 42 dan 3,5 kg/cm2gauge, variasi tebal pipa 4 hingga 20 inchi serta variasi tebal isolasi 1 sampai 4 inch. Laju kondensasi steam dinyatakan dalam suatu persamaan matematis yang merupakan fungsi dari tebal isolasi dan diameter pipa.
Hasil perhitungan menunjukkan bahwa laju kondensasi steam membesar bila tekanan steam naik, tebal isolasi turun, dan diameter pipa membesar. Penghematan yang didapat apabila steam condensate dimanfaatkan sebagai air umpan boiler berasal dari penghematan produksi air demin dan penghematan bahan bakar akibat perbedaan suhu antara steam condensate dan air demin dengan simple payback period selama 0,9 tahun.
Kata kunci: steam condensate, kehilangan panas, laju kondensasi steam, penghematan
As ammonia and urea producer, PT. Pusri consumes a lot of steam, which is used as raw material in ammonia plant, as well as heating medium and turbine driving agent. Steam pressure used in the P-IB Ammonia plant varies from 3.5 to 123 kg/cm2gauge. Distribution system of steam piping to the equipments causes heat loss to the environment. This leads to the production of steam condensate flowing along the pipe. The steam condensate from the pipe (through the steam trap) is directly discharged into the sewer. The present study aimed to determine the rate of steam condensation and to elaborate an economic feasibility to utilize the condensate as boiler feed water in the Ammonia plant P-IB.
Calculation of heat transfer in the pipes was based on the principles of conduction, convection and radiation. The rate of steam condensation was calculated with steam pressure variation from 3.5 to 123 kg/cm2gauge, pipe diameter from 4 to 20-inch and insulation thickness of 1 to 4 inches. The rate of condensation was expressed in a mathematical equation and was a function of insulation thickness and diameter of pipe.
The results showed that the rate of steam condensation rised as steam pressure and pipe diameter increased and insulation thickness decreased. Operating cost reduced if the steam condensate was used as boiler feed water replacing demineralized water. This also caused reduction of fuel consumption and therefore resulted in simple payback period of 0.9 years.
Keywords: steam condensate, heat loss, steam condensation rate,cost reduction
oai:jurnal.ugm.ac.id:article/4943
2017-03-01T05:48:24Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4943
2017-03-01T05:48:24Z
Jurnal Rekayasa Proses
Vol 7, No 1 (2013); 25-29
Pengolahan Gas CO2 Hasil Samping Industri Amoniak Melalui Gasifikasi Batubara yang Telah dipirolisis dengan Menambahkan Ca(OH)2
Sobah, Saripah; Jurusan Teknik Kimia , Sekolah Tinggi Teknologi Industri Bontang
Sulistyo, Hary; Jurusan Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Syamsiah, Siti; Jurusan Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
2014-07-14 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4943
Gas CO2 merupakan salah satu gas rumah kaca yang dianggap memiliki kontribusi terhadap pemanasan global. Industri amoniak menghasilkan emisi CO2 cukup besar dengan faktor emisi 3,273 ton CO2/ton amoniak. Salah satu upaya untuk mengurangi emisi gas CO2 yang dapat dilakukan adalah mengkonversi gas CO2 menjadi gas sintesis (CO) melalui proses gasifikasi batubara. Gas CO merupakan salah satu bahan baku pembuatan metanol. Penelitian ini bertujuan untuk mengetahui seberapa besar gas CO2 dapat dikurangi kadarnya melalui proses gasifikasi arang batubara. Reaksi karbon dari arang batubara dengan gas CO2 pada proses gasifikasi merupakan reaksi endotermis dan berlangsung sangat lambat pada suhu di bawah 1000oC sehingga digunakan Ca(OH)2 sebagai katalisator. Proses gasifikasi batubara dijalankan dalam reaktor fixed bed. Hasil penelitian menunjukkan bahwa gasifikasi arang batubara dengan penambahan Ca(OH)2 pada proses pirolisis dapat mengurangi gas CO2 sampai sebesar 63,17%, sementara untuk gasifikasi tanpa Ca(OH)2 , gas CO2 hanya berkurang sampai 35,2%. Kata kunci: karbondioksida, pemanasan global, gasifikasi, arang batubara, kalsium hidroksida CO2 is one of the greenhouse gases that is considered to cause global warming. Ammonia industry produces emission gas of CO2 in relatively great amount with an emission factor of 3.273 ton CO2/ton ammonia. One of the attempts to reduce CO2 gas emissions is by converting CO2 into syngas (CO) through gasification process. CO is one of the methanol feedstock. This research aimed to find out the amount of CO2 that can be reduced through charcoal gasification process. The reaction of carbon from coal can be reduced through the gasification process. Since the carbon reaction from coal with CO2 gas in the gasification process was an endothermic and occured very slowly at temperatures below 1000°C, Ca(OH)2 was used as a catalyst. The coal gasification process was conducted in a fixed bed reactor. The experimental results showed that coal gasification with the use of Ca(OH)2 in the pyrolysis process could reduce CO2 levels by 63.17%, meanwhile without Ca(OH)2, the CO2 could be reduced only up to 35.2%. Keywords: carbon dioxide, global warming, gasification, charcoal, calcium hydroxide.
oai:jurnal.ugm.ac.id:article/4949
2014-08-16T05:22:49Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4949
2014-08-16T05:22:49Z
Jurnal Rekayasa Proses
Vol 7, No 2 (2013); 30-35
Pelepasan Lambat (Slow Release) Diazinon dari Mikrokapsul Melamin Urea Formaldehid
Lestari, Retno Sulistyo Dhamar
Rochmadi,
Supranto,
2014-07-15 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4949
Konsep dasar slow release adalah pengaturan pelepasan bahan aktif dari mikrokapsul dengan pelapisan dari bahan semi permeable yang tidak larut dalam air atau bahan berpori yang permeable. Pengaturan ketebalan dinding mikrokapsul dapat digunakan untuk mengendalikan kecepatan difusi bahan aktif dari mikrokapsul. Mikrokapsul dengan bahan inti pestisida diazinon dibuat dengan metode insitu polimerisasi, menggunakan melamin, urea, dan formaldehid sebagai bahan dinding mikrokapsul. Polimerisasi dilakukan pada suhu 50˚C, pH 3, dengan waktu homogenisasi 30 menit dan waktu mikroenkapsulasi 2 jam.
Pengujian kecepatan pelepasan pestisida dilakukan dengan merendam sejumlah mikrokapsul melamin urea formaldehid (MUF) dalam aquades dengan pH yang bervariasi dan ketebalan dinding mikrokapsul yang berbeda. Pada penelitian ini, diameter mikrokapsul MUF diperoleh pada kisaran 50 sampai dengan 160 μm. Tanpa penambahan surfaktan, hasil mikrokapsul memiliki ketebalan 13,8 μm. Sedangkan dengan penambahan SDS dan PVA tebal dinding mikrokapsul yang dihasilkan mengalami penurunan sebesar 45%, yaitu menjadi 7,55 μm. Pada mikrokapsul dengan ketebalan 13,8 μm, kecepatan pelepasan pestisida berada pada kisaran 0,52 x 10-6 sampai dengan 1,69 x 10-6 mg/cm2·s. Sedangkan pada mikrokapsul dengan ketebalan 7,55 μm, kecepatan pelepasan diazinon meningkat sebesar 74%, yaitu berada pada kisaran 0,66 x 10-6 sampai dengan 3,4 x 10-6 mg/cm2·s.
Kata kunci : slow release, mikrokapsul melamin urea formaldehid, diazinon
The basic concept of slow release is to control the active ingredient release from microcapsules by means of coating made from either water-insoluble, semi permeable or porous permeable materials. By designing microcapsules wall thickness, the diffusion rate of active ingredient can be controlled. Microcapsules containing diazinon pesticides as a core material have been prepared by in-situ polymerization using melamin urea formaldehyde prepolymer as the wall material. The polymerization had been done at 50 °C and pH 3, with homogenization time of 30 minutes, and microencapsulation time of 2 hours.
To measure pesticide release rate, a number of Melamine Urea Formaldehyde (MUF) microcapsules were soaked in aquadest at various pH and microcapsules wall thicknesses. In this study, the diameter of MUF microcapsules ranged from 50 to 160 μm. Without surfactant addition, the microcapsule wall thickness was 13.8 μm, but by adding SDS and PVA the wall thickness of microcapsule decreased by 45% i.e. around 7.55 μm. For microcapsules with wall thickness of 13.8 μm, the pesticide releasing rate ranged from 0.52 x 10-6 to 1.69 x 10-6 mg/cm2·s. On the other side, the microcapsules with wall thickness of 7.55 μm the pesticide releasing rate dramatically increased by 74% ranged from 0.66 x 10-6 to 3.4 x 10-6 mg/cm2·s.
Keywords: slow release, melamine urea formaldehyde microcapsules, diazinon.
oai:jurnal.ugm.ac.id:article/4950
2014-08-16T05:23:02Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4950
2014-08-16T05:23:02Z
Jurnal Rekayasa Proses
Vol 7, No 2 (2013); 36-44
Prediksi Kesetimbangan Adsorpsi Uranium pada Air dan Sedimen pada Berbagai pH
Utami, Jasmi Budi
Sediawan, Wahyudi Budi
Murachman, Bardi
Wijaya, Gede Sutresna
2014-07-15 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4950
Kegiatan yang melibatkan uranium sebagai bahan bakar nuklir berpotensi menimbulkan pencemaran lingkungan. Uranium merupakan salah satu logam berat berbahaya dan bersifat radioaktif sehingga perlu diketahui penyebarannya di alam. Penelitian ini bertujuan untuk menentukan model kesetimbangan adsorpsi uranium pada air dan sedimen. Model yang disusun diharapkan sesuai untuk berbagai pH air.
Percobaan adsorpsi uranium dijalankan dalam sistem batch. Air limbah sebanyak 100 ml yang mengandung uranium dimasukkan ke dalam erlenmeyer dan pH larutan diatur menjadi 3, 5, 7, atau 9. Sebanyak 0,5 g tanah dimasukkan ke dalam erlenmeyer. Erlenmeyer ditempatkan dalam shaker dengan kecepatan 100 rpm selama 6 jam dan dibiarkan selama 24 jam sampai tercapai kesetimbangan. Filtrat yang terbentuk disaring dan dianalisis menggunakan spektrofotometer.
Lima model kesetimbangan isotermal diajukan untuk mendekati data kesetimbangan. Sebagai hasil, kesetimbangan Chapman cocok dalam mendekati data percobaan pada berbagai pH air. Dari hasil perhitungan diketahui ion UO22+ memiliki nilai parameter α, β, γ masing-masing sebesar 25 mg/g, 2,3 l/mg, dan 18,1 sedangkan untuk ion (UO2)3(OH)7- masing-masing sebesar 19 mg/g, 0,095 l/mg, dan 3,4. Penelitian ini diharapkan bermanfaat sebagai data pendukung bagi analisis dampak lingkungan dalam pembangunan PLTN.
Kata kunci: adsorpsi, kesetimbangan, uranium, prediksi, sedimen, pH
Activities involving uranium as nuclear fuel has potentially polluted the environment. Since uranium is a toxic and radioactive heavy metal, it is necessary to identify its distribution in nature. This study aims to define uranium adsorption equilibrium model in water and sediment. The model is also supposed to be appropriate for various pH of water.
Experiments were performed in a batch system. One hundred mL of waste water for National Atomic Energy Agency (BATAN) containing uranium was placed in an erlenmeyer flask and the pH was varied at 3, 5, 7, or 9. Soil was used as adsorbent. The process was shaken at 100 rpm for six hours and then was left for 24 hours to reach the equilibrium. The resulting filtrate was filtered and analyzed using a spectrophotometer.
Five different isotherm equilibrium models were proposed in order to fit the equilibrium experimental data. It was found that Chapman equilibrium could fit the data more thoroughly than the other models. From the calculation, it was known that UO22+ parameter values of α, β, γ were 25 mg/g-soil, 2,3 l/mg, and 18,1 respectively, while for (UO2)3(OH)7- were 19 mg/g, 0,095 l/mg, and 3,4 respectively. It is expected that this research will be useful as supporting data for environment impact analysis in nuclear power plants development.
Keywords: adsorption, equilibrium, uranium, sediment, pH
oai:jurnal.ugm.ac.id:article/4951
2014-08-16T05:23:14Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4951
2014-08-16T05:23:14Z
Jurnal Rekayasa Proses
Vol 7, No 2 (2013); 45-50
Pembuatan dan Karakterisasi Sabun Susu dengan Proses Dingin
Retnowati, Diah S.
Kumoro, Andri C.
Ratnawati,
Budiyati, Catarina S.
2014-07-15 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4951
Pada penelitian ini, sabun susu dibuat dari larutan susu-NaOH dengan campuran minyak yang terdiri dari minyak sawit, minyak kelapa, minyak jarak dan minyak canola. Tujuan penelitian adalah mempelajari pengaruh perbandingan massa minyak kelapa terhadap minyak canola dan konsentrasi asam sitrat terhadap pH sabun, kekerasan sabun, kemampuan pembentukan busa dan derajat kebersihan. Percobaan dilakukan dengan menuangkan larutan susu-NaOH dan asam sitrat ke dalam campuran minyak dengan perbandingan berat tertentu dan diaduk dengan kecepatan 400 rpm. Setelah terjadi trace (jejak putaran pada larutan) larutan tersebut dicetak dan didiamkan selama 24 jam. Produk sabun dianalisis kekerasan, pH, kemampuan pembentukan busa dan derajat pembersihan setelah dilakukan proses pemeraman selama 4 minggu. Hasil penelitian menunjukkan bahwa 2% massa asam sitrat dapat menurunkan pH sabun dari 10,2 menjadi 9,8, tetapi juga menurunkan tingkat kekerasan, kemampuan pembentukan busa dan kemampuan membersihkan. Perubahan rasio massa minyak kelapa terhadap minyak canola dari 0,5-2, hanya berpengaruh terhadap kekerasan sabun.
Kata Kunci: sabun susu, proses dingin, pH, kekerasan, tingkat kebersihan, pembentukan busa
In this research, cold process was chosen to make soap from lye (NaOH solution) and mixture of palm, coconut, castor, and canola oils with certain ratio. This conducted research is to study the effect of palm to canola oil mass ratio and citric acid concentration on pH, hardness, foaming capacity and the cleansing power of the soap. The soap formation was first conducted by dissolving NaOH in the milk with certain concentration sufficient for the oil mixture saponification.
The solution and citric acid solution were then added to the oil mixture and was stirred at 400 rpm. After trace occurred, the mixture was transferred to a mold and then was put in an open space for 24 hours. The soap was taken out from the mold and was cured for 4 weeks. The hardness, pH, the foaming capacity, and the cleansing power of the resulted soap were analyzed. The result show that the addition of 2% of citric acid reduces the pH of the soap from 10.2 to 9.8, the hardness, the foaming capacity, and the cleansing ability of the soap. The variation of the ratio of the mass of coconut to canola oil from 0.5 to 2 affects only the hardness of the soap.
Keywords: milk-soap, cold process, pH, hardness, cleansing power, lathering
oai:jurnal.ugm.ac.id:article/4952
2014-08-16T05:23:26Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4952
2014-08-16T05:23:26Z
Jurnal Rekayasa Proses
Vol 7, No 2 (2013); 51-57
Pewarnaan Bahan Tekstil dengan Menggunakan Ekstrak Kayu Nangka dan Teknik Pewarnaannya untuk Mendapatkan Hasil yang Optimal
Rosyida, Ainur
Zulfiya, Anik
2014-07-15 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4952
Penelitian ini bertujuan untuk mendapatkan jenis tumbuhan baru yang dapat digunakan sebagai zat pewarna tekstil beserta warna yang dihasilkan. Selain itu untuk mendapatkan teknik/cara pewarnaan bahan tekstil dari serat alam dengan zat pewarna dari ekstrak kayu nangka untuk mendapatkan hasil yang optimal.
Larutan pewarna diperoleh dengan mengekstraksi kayu nangka. Sistim pewarnaan yang digunakan adalah secara perendaman, menggunakan mesin jigger, dengan tahapan proses sebagai berikut : Kain kapas (siap celup) direndam pada larutan ekstrak kayu nangka pada suhu kamar selama 30 menit, setelah itu dilakukan penambahan elektrolit dan pewarnaan diteruskan selama 45 menit. Berikutnya penambahan asam/basa diberikan untuk memperoleh pH yang sesuai dan pewarnaan dilanjutkan selama 30 menit pada suhu kamar. Selanjutnya kain diperas dan difiksasi selama 15 menit pada suhu kamar, setelah proses pewarnaan berakhir kain dilakukan pencucian.
Dari hasil penelitian diketahui, ekstrak kayu nangka dapat digunakan untuk mewarnai bahan tekstil dari serat alam (kain kapas) dengan warna kuning dan coklat. Warna yang dihasilkan sangat tergantung dari jenis fiksator yang digunakan sedangkan ketuaan warna ditentukan oleh pH (suasana larutan) yang digunakan dalam pewarnaan.
Cara/teknik pewarnaan yang digunakan terbukti memperoleh hasil yang optimal karena menghasilkan pewarnaan yang merata, permanen dengan warna tua. Hasil uji ketahanan luntur warna terhadap pencucian dan gosokan diperoleh nilai yang baik, yaitu antara 4-5. Ini menunjukkan larutan ekstrak nangka dapat digunakan sebagai zat warna pada bahan tekstil.
Kata kunci: Ekstrak, kayu nangka, pewarnaan, serat kapas, zat warna alam
This research aims to find a new plant that can be used as textile natural dye substance and the colour it produced. It also purposes to find coloration method of natural fabric by natural dye substance from jackfruit wood exstract to gain the optimum result.
Dye solvent obtained by extracting jackfruit wood. Coloration system used exhaustion by jigger machine which included some steps namely : cotton fabric was impregnated into jackfruit wood extract in room temperature during 30 minutes, then electrolyte and coloration addition during 45 minutes. The next step was acid/base addition to get appropriate pH and coloration continued about 30 minutes in room temperature. Futhermore fabric was squeezed and fixated during 15 minutes in room temperature, the last step was fabric washing.
Based on the research result, jackfruit wood extract can be used for coloring natural fibers (cotton fabric) of textile material into yellow and brown. Final result of coloring depends on fixator used but the color direction depends on pH used in coloration.
The coloration method used shows that it gives optimum result because it produces smooth, permanent and dark colour as well. The result of faded tenacity caused by washing and incitement shows good value, it is 4-5. It proves that jackfruit wood extract can be used as fabric dye substance.
Keywords: extraction, jackfruit wood, dyeing, cotton fiber, natural dye substances
oai:jurnal.ugm.ac.id:article/4953
2014-08-16T05:23:36Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/4953
2014-08-16T05:23:36Z
Jurnal Rekayasa Proses
Vol 7, No 2 (2013); 58-63
Kinetika Reaksi Esterifikasi Palm Fatty Acid Distilate (PFAD) menjadi Biodiesel dengan Katalis Zeolit-Zirkonia Tersulfatasi
Masduki,
Sutijan,
Budiman, Arief
2014-07-15 20:13:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/4953
Krisis energi karena menipisnya cadangan minyak bumi mendorong manusia untuk berinovasi menciptakan sumber energi alternatif. Salah satu sumber energi alternatif yang potensial untuk dikembangkan adalah biodiesel. Produksi biodiesel skala besar terkendala oleh harga bahan baku yang mahal dan cenderung bersaing dengan kebutuhan pangan. Oleh karena itu perlu dicari bahan baku yang lebih murah dan tidak bersaing dengan kebutuhan pangan. Salah satu bahan yang dapat memenuhi kepentingan tersebut adalah Palm Fatty Acid Distilate (PFAD). Penelitian ini bertujuan untuk mempelajari kinetika reaksi esterifikasi PFAD menjadi biodiesel dengan katalis zeolit zirkonia tersulfatasi.
Palm fatty acid distillate (PFAD) sebagai sumber asam lemak diesterifikasi menjadi biodiesel di dalam labu leher tiga yang dilengkapi dengan pemanas, pengaduk dan sistem refluks. Untuk memperoleh data kinetika, sampel diambil pada interval waktu 10 menit untuk dianalisis konversi asam lemaknya. Model kinetika reaksi esterifikasi PFAD menjadi biodiesel didekati dengan reaksi pseudo-homogen orde satu dan reaksi heterogen katalitik.
Hasil penelitian menunjukkan bahwa kedua model kinetika yang diusulkan cukup sesuai dengan data percobaan. Hasil perhitungan model reaksi pseudo-homogen menghasilkan energi aktivasi sebesar 11,60 kJ/mol dan faktor pre-eksponensial sebesar 5,82.1016 s-1. Sedangkan untuk model reaksi heterogen katalitik diperoleh energi aktivasi sebesar 950,46 kJ/mol dan faktor pre-eksponensial sebesar 4,11 x 1010 dm6.gkat-1.mol-1.s-1. Konversi reaksi maksimum sebesar 75,68% diperoleh pada waktu reaksi 80 menit, suhu reaksi 65°C dengan konsentrasi katalis 3% dan perbandingan mol PFAD:metanol = 1:10.
Kata kunci: biodiesel, kinetika, esterifikasi, palm fatty acid distillate, zeolit zirkonia tersulfatasi.
Energy crisis due to depletion of crude oil resources has been a motivation for alternative energy search. Biodiesel becomes a potential among other alternative energy sources. However, large scale biodiesel production is hampered by the raw materials which become expensive and tent to compete with the source of food needs. Therefore, a search for an alternative inexpensive raw material is necessary. Palm fatty acid distilate (PFAD) is one of alternative raw materials can be utilized. The present work objective was to investigate reaction kinetics of PFAD esterification for biodiesel with zirconium sulphated zeolite as catalyst.
PFAD as a source of fatty acid underwent esterification to produce biodiesel in a three necked flask equiped with heater, stirrer and reflux condensor. In order to study the reaction kinetics, samples were collected consecutively every 10 minutes and the conversion of the fatty acid in each sample was determined. Here, two esterification reaction models were proposed i.e. pseudo-homogeneous first order reaction model and heterogeneous catalytic reaction model.
The results showed that calculated conversion for both proposed models were in a good agreement with the experimental data. The pseudo homogeneous reaction model has an activation energy of 11.60 kJ/mole and a pre-exponential factor of 5.821016 s1. Whereas, the heterogeneous reaction model has an activation energy of 950.46 kJ/mole and pre-exponential factor of 4.111010 dm6.g cat1.mol1.s1. The maximum conversion of 75.68% was obtained at 80 minute reaction time, at 65C with the use of 3% catalyst and a PFAD:methanol molar ratio of 1:10.
Keywords: biodiesel, kinetics, esterification, palm fatty acid distillate, zirconium sulphated zeolite.
oai:jurnal.ugm.ac.id:article/5017
2014-09-22T07:17:52Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/5017
2014-09-22T07:17:52Z
Jurnal Rekayasa Proses
Vol 8, No 1 (2014); 1-11
Review Model dan Parameter Interaksi pada Korelasi Kesetimbangan Uap-Cair dan Cair-Cair Sistem Etanol (1) + Air (2) + Ionic Liquids (3) dalam Pemurnian Bioetanol
Hartanto, Dhoni
Triwibowo, Bayu
2014-08-17 20:14:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/5017
Bioetanol merupakan sumber energi terbarukan yang menjanjikan sebagai pengganti sumber energi tidak terbarukan seperti minyak bumi. Pada kondisi tekanan atmosferik, etanol memiliki azeotrop dengan air sehingga pemisahan dengan menggunakan distilasi biasa tidak dapat dilakukan. Beberapa proses pemurnian etanol adalah melalui distilasi ekstraktif dan ekstraksi cair-cair dengan menggunakan entrainer berupa senyawa baru yang ramah lingkungan dan dapat digunakan kembali (reuse) yaitu ionic liquids. Penelitian intensif sistem etanol (1) + air (2) + ionic liquids (3) telah dilakukan oleh beberapa peneliti mengenai kesetimbangan uap-cair (VLE), kesetimbangan cair-cair (LLE) yang menghasilkan data kesetimbangan. Penelitian tersebut juga menghasilkan parameter-parameter interaksi yang diperoleh berdasarkan hasil korelasi data kesetimbangan tersebut dengan model Nonrandom two-liquid (NRTL), Electrolyte-nonrandom two-liquid (e-NRTL), Universal quasi-chemical (UNIQUAC), dan persamaan Antoine serta hasil prediksi dengan menggunakan model UNIQUAC Functional-group activity coefficients (UNIFAQ). Model-model dan parameter-parameter interaksi biner termodinamika tersebut dapat digunakan untuk keperluan desain, optimasi, serta kontrol kolom distilasi ekstraktif dan ekstraksi cair-cair dalam proses pemurnian bioetanol. Artikel ini menyajikan review tentang model-model dan parameter-parameter interaksi biner untuk 43 sistem etanol (1) + air (2) + ionic liquids (3) sehingga dapat diketahui model dan parameter termodinamika yang sesuai untuk digunakan. NRTL merupakan model yang paling banyak digunakan untuk mengkorelasi data kesetimbangan pada 40 sistem dan dapat mengkorelasi kesetimbangan uap-cair dan cair-cair dengan baik sesuai dengan karakteristik NRTL yang sesuai untuk sistem polar tekanan rendah. Hal tersebut ditunjukkan dengan nilai root mean square deviation (RMSD) untuk ∆y dan ∆T dan average relative deviation (ARD) yang kecil serta dapat mem-fitting grafik data kesetimbangan tersebut dengan baik.
Kata kunci: bioetanol, ionic liquids, parameter interaksi biner, NRTL
Bioethanol is a promising renewable energy resource which can substitute non-renewable energy such as fossil-fuel. Ethanol and water produce azeotropic point in atmospheric pressure condition which can not be separated by ordinary distillation. New class of eco-friendly compounds to be used as entrainer are known as ionic liquids. These ionic liquids are used experimentally in extractive distillation and liquid-liquid extraction. Many researches have been conducted in ethanol (1) + water (2) + ionic liquids (3) systems including vapor-liquid equilibrium (VLE) and liquid-liquid equilibrium (LLE). These researches also produce binary interaction paramaters obtained from equilibrium data correlation using Nonrandom two-liquid (NRTL), Electrolyte-nonrandom two-liquid (e-NRTL), Universal quasi-chemical (UNIQUAC), and Antoine equation. UNIQUAC Functional-group activity coefficients (UNIFAQ) was also used to predict the equilibrium data. Models and binary interaction parameters were used for design, optimization, and control of extractive distillation column and liquid-liquid extraction in bioethanol purification. This paper provides a critical review of models and binary interaction parameters for 43 ethanol (1) + water (2) + ionic liquids (3) systems to obtain appropriate models and binary interaction parameters. Generally, NRTL is the most frequent used model, it is used in 40 systems. NRTL provides satisfactory results in vapor-liquid equilibrium and liquid-liquid equilibrium data correlation due to its characteristics which can correlate well in low pressure polar system. It is shown by small number of root mean square deviation (RMSD) for ∆y and ∆T and average relative deviation (ARD). It can also fit equilibrium data behavior with a good agreement.
Keywords: bioethanol, ionic liquids, binary interaction parameters, NRTL
oai:jurnal.ugm.ac.id:article/5018
2017-03-01T05:47:53Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/5018
2017-03-01T05:47:53Z
Jurnal Rekayasa Proses
Vol 8, No 1 (2014); 12-19
Kitosan dari Limbah Udang sebagai Bahan Pengawet Ayam Goreng
Harjanti, Ratna Sri; Program Studi Teknik Kimia, Politeknik LPP. Jl. LPP 1 A, Balapan, Yogyakarta
2014-08-17 20:14:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/5018
Industri pengolahan udang banyak menimbulkan hasil samping berupa limbah kulit udang yang belum dimanfaatkan secara optimal. Hal ini menyebabkan limbah kulit udang kurang memiliki nilai ekonomis dibanding dengan mengolahnya menjadi kitin dan kitosan. Kitosan banyak digunakan di berbagai industri antara lain sebagai bahan pengawet pengganti formalin. Bahan pengawet merupakan bahan tambahan makanan yang dibutuhkan untuk mencegah aktivitas mikroorganisme agar kualitas makanan senantiasa terjaga sesuai dengan harapan konsumen. Kemampuan kitosan dalam menekan pertumbuhan bakteri disebabkan kitosan memiliki polikation bermuatan positif yang mampu menghambat pertumbuhan bakteri dan kapang. Dalam penelitian ini akan dilakukan pembuatan kitosan dengan variasi konsentrasi NaOH, sehingga akan diperoleh variasi rendemen dan derajad deasetilasi. Kulit limbah udang mengalami proses deproteinasi dengan larutan NaOH (3,5% b/v) selama dua jam pada suhu 65°C dan proses demineralisasi dalam larutan HCl 1 N (1 gram sampel : 15 mL larutan HCl) selama satu jam pada suhu kamar. Proses deasetilasi dilakukan dengan memanaskan kitin dalam larutan NaOH (30%, 40%, 50%, dan 60% b/v) selama 4 jam pada suhu 100°C. Selanjutnya dilakukan pengamatan pengaruh derajad deasetilasi terhadap kemampuan kitosan sebagai bahan pengawet. Pengamatan ini dilakukan dengan mengaplikasikan kitosan dalam pengawetan daging ayam. Dipilih daging ayam karena sekarang ini banyak sekali dibuat ayam goreng yang dijual dalam gerobak-gerobak di pinggir jalan yang menggunakan bahan kimia berbahaya sebagai pengawetnya. Kitosan yang berasal dari limbah kulit udang dapat digunakan sebagai bahan pengawet daging ayam, tanpa mengubah rasa dan aroma khas daging ayam. Waktu perendaman terbaik adalah 45 menit pada kitosan 2%. Sedangkan aplikasi kitosan sebagai bahan pengawet diperoleh kondisi terbaik pada derajad deasetilasi 70,34%. Kata kunci: kitosan, limbah udang, pengawet makanan, ayam goreng Shrimp industries have to deal with shell solid waste. On the other hand, this shell solid waste can be utilized to produce citin and citosan. One of the beneficiations of citosan is for food preservation. This ability is based on the existence of poly cation with positive charge that is responsible for the inhibition of bacteria growth. In this study, NaOH was varied to produce citosan from shrimp shell resulting rendemen and deasetilation degree. Deproteination of the shrimp shell was done using NaOH (3,5% b/v) for 2 hours, at temperature of 65°C, while demineralization was conducted using HCl 1 N (1 gram of sample: 15 mL of HCl) for 1 hour at room temperature. Deasetilation was done by heating citin in NaOH with concentration of 30%, 40%, 50%, and 60% b/v for 4 hours at temperature of 100°C. Further, observation on the ability of resulted citosan as food preservation was conducted. Chicken meat was choosen as sample to represent the abundance restaurants selling these product. It has been found that citosan from shrimp shell solid waste can be utilized as food preservation agent for chicken meat without changing the taste and texture of the meat. The optimum condition is 45 minutes with citosan concentration of 2% with deasetilation degree of 70,34%. Keywords: citosan, shrimp shell solid waste, food preservation, fried chicken.
oai:jurnal.ugm.ac.id:article/5019
2014-09-22T07:17:28Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/5019
2014-09-22T07:17:28Z
Jurnal Rekayasa Proses
Vol 8, No 1 (2014); 20-24
Enzymatic Hydrolysis of Sorghum Bagasse to Readily Fermentable Sugar for Bioethanol
Soeprijanto,
Indriawati, Katherin
Abdulgani, Nurlita
2014-08-17 20:14:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/5019
Produksi gula dari bagase sorghum menggunakan enzim selulase dan selobiase dilakukan dalam kultur batch. Tujuan percobaan adalah mempelajari pengaruh beban bagase sorghum dan waktu pretreatment kapur terhadap produksi gula dan yield gula. Pretreatment kapur dilakukan dalam 1000 ml labu leher tiga dengan beban kapur 0,1 g Ca(OH)2 /g sorghum bagasse dan ditambah dengan 500 ml air distilasi. Pengaruh waktu pretreatment (1, 2, 3, dan 4 jam) pada suhu 100°C dan pengaruh beban biomassa (5, 10, 15 % w/v) pada hidrolisis enzim untuk menghasilkan gula. Hasil penelitian menunjukkan bahwa konsentrasi gula maksimum dicapai sebesar 28,04 g/l dalam waktu pretreatment 4 jam; dan yield maksimum gula diperoleh 0,4 g glukose/ g biomassa dengan beban biomassa 5% (w/v).
Kata kunci: Bagase sorghum, selulase, selobiase, hidrolisis enzim, kultur batch, pretreatment kapur
Production of sugar from sorghum bagasse using enzyme of cellulase and cellobiase in a batch culture was conducted. The purpose of this experiment was to study of the effect of sorghum baggase loadings and lime pretreatment time on production and yield of sugar. Lime pretreatment was carried out in a 1000 ml three-neck flask with a lime loading of 0.1 g Ca(OH)2 /g sorghum bagasse and added with 500 ml distilled water. Effects of pretreatment time course (1, 2, 3, and 4 h) at temperature of 100°C and biomass loading (5, 10, 15 % w/v) were observed to produce sugar. The results showed that maximum concentration of sugar obtained was 28.04 g/l with a pretreatment time of 4 h; and the maximum yield of sugar obtained was 0.4 g glucose/ g biomass with a biomass loading of 5% (w/v).
Keywords: Batch culture, cellulose, cellobiase, Enzymatic hydrolysis, ime pretreatment, sorghum bagasse
oai:jurnal.ugm.ac.id:article/5020
2014-09-22T07:17:34Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/5020
2014-09-22T07:17:34Z
Jurnal Rekayasa Proses
Vol 8, No 1 (2014); 25-32
Pemanfaatan Abu Sekam Padi pada Ozonisasi Minyak Goreng Bekas untuk Menghasilkan Biodiesel
Riadi, Lieke
Sapei, Lanny
Kristiani, Yosephine
Sugianto, Octovania
2014-08-17 20:14:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/5020
Penggunaan abu sekam padi sebagai katalis pendukung pada ozonasi minyak goreng bekas untuk menghasilkan biodiesel dipelajari pada penelitian ini. Ozonasi minyak goreng bekas termasuk proses yang hemat energi dan ramah lingkungan karena menggunakan minyak goreng bekas sebagai bahan baku biodiesel serta suhu reaksi yang relatif rendah yaitu pada suhu kamar. Proses pembuatan biodiesel dilakukan dengan mereaksikan minyak goreng bekas dan metanol dengan bantuan katalis KOH pada sebuah reaktor. Gas ozon dialirkan secara kontinu dalam reaktor berpengaduk pada suhu 30oC dan tekanan atmosfer. Pengaruh penggunaan abu sekam padi sebagai supporting catalyst terhadap konsentrasi metil ester yang dihasilkan dikaji dalam percobaan ini. Abu yang digunakan adalah abu hitam (pemanasan pada 350oC) dan putih (pemanasan pada 750oC) dengan konsentrasi masing-masing sebesar 0,5 ; 1 ; 1,5% (b/b). Produk metil ester dikarakterisasi menggunakan Gas Chromatography untuk mengetahui jumlah metil ester rantai pendek (SCME) maupun metil ester rantai panjang (LCME). Di samping itu, dilakukan juga uji densitas dan viskositas, abu yang digunakan diuji dengan analisa XRD dan BET. Konsentrasi SCME paling tinggi dihasilkan pada variasi abu putih dengan konsentrasi 1,5%. Namun, penambahan abu tidak berpengaruh secara signifikan terhadap pembentukan LCME. Dengan demikian, abu putih lebih berperan sebagai supporting catalyst dibandingkan abu hitam.
Kata kunci: biodiesel, minyak goreng bekas, abu sekam padi, proses ozonasi,metil ester rantai pendek,metil ester rantai panjang
Biodiesel is one of the alternatives for the shortage of fossil fuel. In this experiment biodiesel from waste cooking oil which is made using an ozonation process was studied. The process is energy extensive and environmentally friendly because of the use waste cooking oil as a raw material and the experiment was carried out at low reaction temperature which is room temperature. Waste cooking oil was reacted with methanol, KOH as the base catalyst, and ozone that was continually flowed into a stirred reactor at 30oC and atmospheric pressure. The effect of rice hulk ash addition as the supporting catalyst on methyl esters concentrations was observed in this experiment. Two different types of ashes were used, namely black (heating at 350oC) and white (heating at 750oC) with the concentrations of 0.5; 1; 1.5% (w/w). Methyl esters products were characterized using GC apparatus for Short Chain Methyl Ester (SCME) and Long Chain Methyl Ester (LCME) concentrations. They were also analyzed in terms of density and viscosity. The ashes were characterized by XRD and BET. The highest amount of SCME was achieved at the white ash concentration of 1.5%. However, the ash additions seemed not significant on the LCME production. Thus, the white ash was more useful as a supporting catalyst than the black one.
Keywords: biodiesel, used cooking oil, rice hulk ash, ozonation process, short chain methyl ester, long chain methyl ester
oai:jurnal.ugm.ac.id:article/5021
2017-03-01T05:47:53Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/5021
2017-03-01T05:47:53Z
Jurnal Rekayasa Proses
Vol 8, No 1 (2014); 33-39
Pemanfaatan LNG Sebagai Sumber Energi di Indonesia
Santoso, Nurhadi Budi; PT Cipta Reka Mandiri, Gedung Sinar Kasih, Lt. 5, Jl. Dewi Sartika No. 136D, Jakarta
2014-08-17 20:14:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/5021
Kebutuhan energi di Indonesia terutama penggunaan diesel/solar setiap tahun selalu meningkat, dikarenakan jumlah kilang di Indonesia tidak bertambah dan produksi minyak mentah akhir-akhir ini terjadi penurunan. Sehingga penambahan konsumsi tersebut dipenuhi dengan penambahan impor minyak solar/diesel, hal ini semakin memberatkan keuangan negara. Kondisi tersebut diatas harus segera dicarikan jalan keluarnya. Salah satu sumber energi alternatif pengganti solar adalah LNG. Dengan dipakainya LNG sebagai salah satu sumber energi diharapkan akan mengurangi impor solar/disel, sehingga menghemat devisa negara serta meningkatkan daya saing industri domestik. Indonesia merupakan produsen utama LNG dunia, hampir semua LNG yang diproduksi diekspor ke luar negeri utamanya ke Jepang, Korea dan China. LNG sampai saat ini belum banyak dimanfaatkan oleh masyarakat maupun industri domestic sebagai sumber energi, hal ini dikarenakan kurang adanya sosialisasi manfaat dari LNG. Untuk bisa memanfaatkan LNG sebagai bahan bakar pengganti solar maka perlu dibangun fasilitas dan infrastruktur yang baik meliputi moda transportasi, teknologi penyimpanan, maupun teknologi converter kit sehingga LNG bisa digunakan untuk menggantikan solar pada mesin disel yang ada. Berdasarkan cost saving analysis, penggunaan dual fuel (Diesel dan LNG) pada mesin, yaitu memanfaatkan LNG pada mesin diesel dapat menghasilkan penghematan sebesar 20-25% bila dibandingkan dengan menggunakan single fuel saja dengan solar. Kata kunci: LNG, diesel, isotank, converter kit, energi. The need of energy supplies in Indonesia, especially on diesel demand is increasing every year. However, this increase could not be fulfilled by national oil based energy supply due to the decrease of oil production and there has not been significant increase in term of oil fractionation plants. As a consequence, diesel import could not be avoided resulting an additional burden in nation budgeting. In order to solve this problem, LNG might be an alternative. Thus, diesel import can be eliminated; furthermore, domestic industries can be more competitive. Although Indonesia is one of the major LNG producers, most of the LNG production is exported to Japan, Korea, and China, but LNG has not been utilized by the society as well as domestic industries. A massive socialization of the utilization of LNG to replace diesel energy should be conducted. Moreover, facilities and infrastructures including transportation, storages, and converter kits have to be built to support this conversion process. Based on the cost saving analysis, the use of dual fuel (diesel and LNG) in a machine could possibly save 20-25% in comparison to that machine using single fuel (diesel). Keywords: LNG, diesel, isotank, converter kit, energy.
oai:jurnal.ugm.ac.id:article/8130
2017-02-22T00:13:48Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/8130
2017-02-22T00:13:48Z
Jurnal Rekayasa Proses
Vol 7, No 2 (2013)
test
Kusumastuti, Yuni
2015-11-27 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/8130
en
Test test
oai:jurnal.ugm.ac.id:article/11371
2016-05-26T07:11:29Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/11371
2016-05-26T07:11:29Z
Jurnal Rekayasa Proses
Vol 8, No 2 (2014); 40-48
Dekolorisasi dan Deoilisasi Parafin menggunakan Adsorben Zeolit, Arang Aktif dan Produk Pirolisis Batu Bara
Murachman, Bardi
Putra, Eddie Sandjaya
Wulandary,
2016-05-26 14:10:14
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/11371
Indonesian wax production was reaching 50277 barrels in 2009. Although the wax production rate in Indonesia is quite high, it is still not enough to fulfill the demand. Therefore, Indonesia has to import wax from China. Unfortunately, Indonesian wax qualities, especially related to colour and hardness, are less compared with those from China. Local wax is more brownish yellow, soft and easily melted compared with the wax from China which is whiter, harder and difficult to melt.
Many research activities have been conducted to improve quality of local wax. Among of them is with the use of adsorption method with adsorbent.Various adsorbents can be used, including activated carbon, zeolite, and coal pyrolysis product. The present work aim was to find the ability of forementioned adsorbent in purpose to improve the quality of wax, i.e. colour and texture, by decolorization dan deoilization process. Adsorbent was added to the wax at 90C and mixing was then conducted. Parameters under investigation were the influence of the ratio of wax to adsorbent and the optimum mixing time.
Based on reduction of oil content and colour intensity, the best wax -adsorbent ratio was 6 : 6 with a mixing time of 50 minutes. Zeolite gives the best adsorption properties and high effectivity in deoilization and decolorization process.
Keywords : adsorption, decolorization, deoilization, adsorbent, wax
Produksi lilin di Indonesia mencapai 50.277 barrel pada tahun 2009. Walaupun produksi lilin di dalam negeri cukup tinggi, jumlah tersebut belum mencukupi permintaan dari masyarakat sehingga masih harus mengimport lilin dari Cina. Sayangnya, lilin dalam negeri kualitasnya lebih rendah dibandingkan lilin dari Cina. Lilin dalam negeri masih berwarna kuning kecoklatan, lunak dan mudah meleleh sedangkan lilin produksi Cina jauh lebih putih, keras dan lebih lama meleleh.
Banyak penelitian telah dilakukan untuk meningkatkan kualitas lilin. Proses adsorbsi menggunakan adsorben merupakan salah satunya. Berbagai jenis adsorben dapat digunakan, seperti arang aktif, zeolite, maupun produk pirolisis batu bara. Penelitian ini bertujuan mengetahui kemampuan adsorpsi dari masing-masing adsorben tersebut dalam meningkatkan kualitas, warna dan struktur lilin, dengan cara dekolorisasi dan deoilisasi. Adsorben ditambahkan ke lilin pada suhu sekitar 90C dan dilakukan pengadukan. Parameter yang dikaji dalam penelitian ini adalah pengaruh rasio lilin : adsorben dan waktu pengadukan optimum.
Hasil penelitian menunjukkan bahwa rasio lilin : adsorben terbaik adalah 6:6 bila dilihat dari pengurangan kadar minyak dan kadar zat warna, dengan waktu pengadukan terbaik adalah 50 menit. Zeolit memberikan sifat penjerapan terbaik dan efektivitas tinggi dalam proses deoilisasi dan dekolorisasi.
Kata kunci : adsorpsi, dekolorisasi, deoilisasi, adsorben, lilin
oai:jurnal.ugm.ac.id:article/11372
2016-05-26T07:11:59Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/11372
2016-05-26T07:11:59Z
Jurnal Rekayasa Proses
Vol 8, No 2 (2014); 49-54
Suhu dan Rasio Kukus Optimum pada Proses Gasifikasi Kukus Berkatalis K2CO3 terhadap Arang Batu bara Lignit Hasil Pirolisis dengan Laju Pemanasan Terkontrol
Tristantini, Dewi
Suwignjo, Ricky Kristanda
2016-05-26 14:10:14
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/11372
In order to fulfill the raw material needs of Fischer Tropsch process for producing synthethic fuel (synfuel), high yield of synthesis gas (syngas) with H2/CO ratio ≈ 2.0 should be obtained from lignite coal gasification. Steam gasification can enhance H2 composition in syngas. Lower activation energy of gasification reaction can be obtained using K2CO3 catalyst during the process. Pyrolysis step with controlled heating rate will affect pore surface area of char which will influence the composition and yield of syngas. In this study, lignite char from pyrolysis with controlled heating rate with 172.5 m2/g surface area and K2CO3 catalyst was fed in fixed bed steam gasification reactor. Steam to char mass ratio (2.0; 3.0; 4.0) and gasification temperature (675; 750; 825C) was varied. Optimum condition for syngas production obtained in this study was steam gasification at 675C with steam/char mass ratio 2.0. This condition will produce syngas with H2/CO ratio 2.07 and gas yield 1.128 mole/mole C (45% carbon conversion).
Keywords: lignite, controlled pyrolysis, catalytic steam gasification, fixed bed reactor
Untuk memenuhi persyaratan bahan baku pembuatan bahan bakar cair sintetis (synfuel) melalui proses Fischer Tropsch, diperlukan proses gasifikasi batu bara lignit yang menghasilkan gas sintesis dengan rasio H2/CO ≈ 2,0 dan yield gas yang tinggi. Metode gasifikasi kukus dapat meningkatkan komposisi H2 dalam gas sintesis. Energi aktivasi reaksi gasifikasi dapat diturunkan dengan menggunakan katalis K2CO3. Laju pemanasan terkontrol pada tahap pirolisis menentukan ukuran pori arang yang berpengaruh pada komposisi dan yield gas sintesis. Penelitian ini dilakukan dengan mengumpankan arang batu bara lignit hasil pirolisis dengan laju pemanasan terkontrol yang memiliki luas permukaan pori 172,5 m2/g bersama dengan katalis K2CO3 ke dalam reaktor unggun tetap. Rasio massa kukus/arang yang ditambahkan bervariasi 2,0; 3,0; 4,0 dan suhu gasifikasi 675, 750, 825C. Hasil penelitian ini menunjukkan bahwa kondisi reaksi gasifikasi yang sesuai untuk produksi gas sintesis bahan baku proses Fischer Tropsch adalah reaksi gasifikasi berkatalis K2CO3 pada suhu 675C dan rasio massa kukus/arang 2,0. Kondisi ini menghasilkan gas sintesis dengan rasio H2/CO 2,07 dengan yield gas 1,128 mol/mol C (45% konversi karbon).
Kata kunci: lignit, pirolisis terkontrol, gasifikasi kukus berkatalis, reaktor unggun tetap
oai:jurnal.ugm.ac.id:article/11373
2016-05-26T07:12:09Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/11373
2016-05-26T07:12:09Z
Jurnal Rekayasa Proses
Vol 8, No 2 (2014); 55-61
Synthesis of Oligoesters Plastic Film from Polylactic Acid with Mono Ester Plasticizer of Wood Flour and Rice Bran and its Hydro Degradation
Azwar, Edwin
2016-05-26 14:10:14
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/11373
Composites of polylactic acid (PLA) with mono ester plasticizer (MEP) from wood flour and rice bran were prepared to evaluate the effect of MEP filler content on the mechanical, functional, thermal, and morphological properties of the composites and its degradation. The SEM study provided evidence that there was sufficient interfacial adhesion between the PLA matrix and the MEP from wood flour and rice bran filler. This was likely a result of mechanical interlocking among them. An addition of 10 and 30% MEP from wood flour or rice bran resulted in an improvement of strain and tensile properties of the composite. The composites of PLA and MEP from wood flour and rice bran experienced degradation through hydrolysis of regions that have crystalline structure.
Keywords: polylactic acid, fiber, cellulose, wood flour, rice bran
Komposit dari polylactic acid (PLA) dan mono ester plasticizer (MEP) dari tepung kayu dan bekatul disiapkan untuk mengevaluasi pengaruh jenis bahan isian MEP terhadap sifat mekanis, fungsi, sifat termal, dan morfologis komposit tersebut beserta reaksi degradasinya. Hasil analisis dengan SEM menunjukkan bahwa terdapat interfacial adhesion yang cukup besar antara matriks PLA dan MEP dari tepung kayu dan bekatul, yang dapat disebabkan oleh mechanical interlocking antara keduanya. Penambahan 10 dan 30% MEP tepung kayu dan bekatul menyebabkan perbaikan regangan (strain) dan tegangan tarik (tensile). Komposit PLA dan MEP dari tepung kayu dan bekatul mengalami degradasi dengan hidrolisis pada bagian yang berstruktur kristal.
Kata kunci: polylactic acid, serat, selulosa, tepung kayu, bekatul
oai:jurnal.ugm.ac.id:article/11374
2016-05-26T07:12:19Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/11374
2016-05-26T07:12:19Z
Jurnal Rekayasa Proses
Vol 8, No 2 (2014); 62-68
Sintesis ZSM-5 dari Coal Fly Ash (CFA) dengan Sumber Silika Penambah yang Berasal dari Abu Sekam Padi: Pengaruh Rasio SiO2/Al2O3 Terhadap Kristalinitas Produk
Metta, Azlia
Ginting, Simparmin Br
Saputra, Hens
2016-05-26 14:10:14
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/11374
Coal Fly Ash and rice husk ash can be utilized by converting it into ZSM-5 synthetic zeolite. One of the influencing factors of ZSM-5 synthetis is ratio of SiO2/Al2O3. Synthesis of ZSM-5 was carried out in an autoclave at a temperature of 180°C with a variation of the ratio of SiO2/Al2O3, namely 20, 30, 40, 50 and 60 mol/mol during 24 hour crystallization using TPABr template. Characterization of ZSM-5 was conducted using X-ray Diffraction, Scanning Electron Microscopy, Adsorption-Desorption Analysis of Nitrogen and Acidity. The results showed that the ZSM-5 was formed in all the variations of SiO2/Al2O3 ratios with the highest percent crystallinity of 52.83%, at the ratio of 50 mol/mol. All products are still in accompany with the formation of side products such as Analsime and Silica Oxide. The ZSM-5 crystal product was in hexagonal shape. Results from Adsorption-Desorption Analysis of Nitrogen indicated that all products were mesoporous materials.
Keywords: crystallinity, mesopore, ZSM-5, silica, rice husk, SiO2/Al2O3 ratio
Limbah Coal Fly Ash dan abu sekam padi dapat dimanfaatkan dengan mengkonversi limbah menjadi zeolit sintesis ZSM-5. Salah satu faktor yang mempengaruhi sintesis ZSM-5 adalah rasio SiO2/Al2O3. Sintesis ZSM-5 dilakukan di dalam autoklaf pada suhu 180C dengan variasi rasio SiO2/Al2O3 yaitu 20, 30, 40, 50 dan 60 mol/mol selama waktu kristalisasi 24 jam menggunakan template TPABr. Karakterisasi ZSM-5 menggunakan metode Difraksi Sinar X, Scanning Electron Microscopy, Adsorpsi – Desorpsi Nitrogen dan Analisis Keasaman. Hasil penelitian menunjukkan bahwa ZSM-5 terbentuk pada semua variasi SiO2/Al2O3. Persen kristalinitas produk ZSM-5 sebesar 52,83%, ada pada rasio 50 mol/mol. Semua produk masih disertai terbentuknya produk samping seperti Analsime dan Silika Oksida. Kristal ZSM-5 yang dihasilkan berbentuk heksagonal. Hasil Analisis Adsorpsi-Desorpsi nitorgen mengindikasikan bahwa semua sampel adalah material mesopori.
Kata kunci: kristalinitas, mesopori, ZSM-5, sekam, rasio SiO2/Al2O3
oai:jurnal.ugm.ac.id:article/11375
2016-05-26T07:12:31Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/11375
2016-05-26T07:12:31Z
Jurnal Rekayasa Proses
Vol 8, No 2 (2014); 69-75
Pembuatan Kitosan dari Kulit dan Kepala Udang Laut Perairan Kupang Sebagai Pengawet Ikan Teri Segar
Mardyaningsih, Mamiek
Leki, Aloysius
Rerung, Oktovianus D.
2016-05-26 14:10:14
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/11375
The objective of the study is to examine the feasibility of chitosan from skin and head of the shrimp from Kupang seas as a fresh anchovy preservative. The study was conducted through two stages: chitosan production and application of chitosan as fresh anchovy preservative. Chitosan production generally starts from shrimp waste flour manufacture, deproteinization, demineralization and deacetilation. The concentration of chitosan as fresh anchovy preservative is 1.5%. Chitosan characterization includes water, protein, ash and fat and fresh anchovy test which covers the organoleptic test, microbiology and proximate test. The results showed that chitosan has flake shape with moisture content of 2.81%, ash 0.75%, nitrogen 7.26%, clear transparent color and 79.11% degree of deacetilation. Characteristics of chitosan meet Proptan Laboratoris standards. Storage life of fresh anchovy soaked in chitosan is 3 days at room temperature storage, while for normal fresh anchovy is only 1 day. Chitosan can extend the storage life, increase the rate of protein fish, preserve the taste of fresh anchovy and make the fresh anchovy more shinny.
Keywords: shrimp waste, chitosan, preservative, fresh anchovy
Penelitian ini bertujuan untuk mengkaji kelayakan kitosan dari kulit dan kepala udang laut perairan Kupang sebagai pengawet ikan teri segar. Penelitian ini dilakukan melalui 2 tahap yaitu pembuatan kitosan dan aplikasi kitosan sebagai pengawet ikan teri segar. Pembuatan kitosan secara umum dimulai dari pembuatan tepung limbah udang, deproteinasi, demineralisasi dan deasetilasi. Aplikasi pengawetan ikan teri segar menggunakan kitosan dengan konsentrasi 1,5%. Karakterisasi kitosan meliputi kadar air, abu, protein dan derajat deasetilasi. Uji ikan teri segar meliputi uji organoleptik, mikrobiologi dan uji proksimat. Hasil penelitian menunjukkan kitosan yang dihasilkan memiliki bentuk partikel serpihan, kadar air 2,81%, kadar abu 0,75%, kadar nitrogen 7,26%, warna larutan jernih dan derajat deasetilasi 79,11%. Karakteristik kitosan sudah memenuhi standar Proptan Laboratoris. Kitosan dapat memperpanjang umur penyimpanan dan meningkatkan kadar protein. Umur simpan ikan teri segar yang dicelup kitosan adalah 3 hari pada penyimpanan suhu kamar, sedangkan untuk ikan teri segar kontrol hanya 1 hari. Kitosan tidak merubah cita rasa ikan teri segar dan membuat penampakan ikan teri segar mengkilat.
Kata kunci: limbah udang laut, kitosan, pengawet, ikan teri segar
oai:jurnal.ugm.ac.id:article/11376
2017-03-20T12:52:57Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/11376
2017-03-20T12:52:57Z
Jurnal Rekayasa Proses
Vol 8, No 2 (2014); 76-81
Pengaruh Detoksifikasi dan Konsentrasi Substrat Terhadap Produksi Biohidrogen dari Hirolisat Ampas Tahu
Husin, Amir; Teknik Kimia, Fakultas Teknik, Universitas Sumatera Utara; Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Sarto, Sarto; Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Syamsiah, Siti; Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Prasetyo, Imam; Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
2016-05-26 14:10:14
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/11376
The effect of detoxification and substrate concentration on fermentative hydrogen production by mixed cultures was investigated in batch experiments using tofu solid waste (TSW) hydrolysate as substrate. TSW as the by product of tofu processing industry was hydrolyzed using diluted hydrochloric acids as catalyst (0.5% wt HCl, 104C and 30 minutes). After neutralized by Ca(OH)2 (aq) and then treated by activated carbon for one hour, the hydrolysate was used for biohydrogen production. The experimental results show that, during fermentative hydrogen production under mesophilic condition and initial pH 6.5 were influenced both substrates without/with detoxification. The maximal hydrogen yield of 4.9 mmol/g reducing sugar (RS) were obtained at detoxified substrate consentration of 2 g GT/L. Detoxification has also shown to shortened lag phase of fermentation (). Adaptation time of microbes during fermentation was reduced from 20 into 13.25 hours for fermentation without/with detoxification respectively at initial substrate concentration of 2 g GT/L. Key words : hydrolysate, tofu solid waste, detoxification, hydrogen, fermentation Pengaruh detoksifikasi dan konsentrasi substrat terhadap produksi hidrogen fermentatif dengan kultur campuran diinvestigasi dalam percobaan batch menggunakan hidrolisat ampas tahu sebagai substrat. Ampas tahu sebagai produk samping industri pengolahan tahu dihidrolisis menggunakan katalis asam encer (0,5% berat HCl, 104C dan 30 menit). Setelah dinetralkan dengan larutan Ca(OH)2 dan dikenakan perlakuan dengan karbon aktif (1,5% berat/volum), hidrolisat siap digunakan untuk produksi hidrogen. Hasil percobaan menunjukkan, bahwa pada kondisi mesofilik dan pH awal 6,5, produksi hidrogen meningkat dan yield (mmol H2/g gula tereduksi) menurun dengan meningkatnya konsentrasi substrat awal, baik pada system tanpa detoksifikasi maupun dengan detoksifikasi. Yield H2 maksimum 4,9 mmol H2/g gula tereduksi (GT) diperoleh bila hidrolisat tanpa detoksifikasi diinkubasi pada konsentrasi substrat awal 2 g GT/L. Hasil ini 25% lebih tinggi jika dibandingkan dengan substrat yang tanpa detoksifikasi. Proses detoksifikasi hidrolisat menggunakan karbon aktif mempengaruhi kinerja proses fermentasi dengan berkurangnya lama waktu fase adaptasi mikroba (). Pada konsentrasi substrat 2 g/L, lama waktu fase adaptasi mikroba berkurang dari 20 menjadi 13,25 jam berturut-turut untuk hidrolisat tanpa detoksifikasi dan dengan detoksifikasi. Kata kunci : hidrolisat, ampas tahu, detoksifikasi, hidrogen, fermentasi
oai:jurnal.ugm.ac.id:article/19145
2018-05-10T01:28:41Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/19145
2018-05-10T01:28:41Z
Jurnal Rekayasa Proses
Vol 11, No 1 (2017); 19-23
Pengaruh Penambahan EM-4 dan Molasses terhadap Proses Composting Campuran Daun Angsana (Pterocarpus indicun) dan Akasia (Acasia auriculiformis)
Magna Kusuma, Ahmad Pinandita; Prodi Teknik Kimia, Fakultas Teknik, Universitas Sebelas Maret
Biyantoro, Derry; Prodi Teknik Kimia, Fakultas Teknik, Universitas Sebelas Maret
margono, Margono; Prodi Teknik Kimia, Fakultas Teknik, Universitas Sebelas Maret
2017-08-02 20:45:07
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/19145
id-ID
Dried leaves in the Universitas Sebelas Maret (UNS) area, which consist of angsana (Pterocarpus indicus) and acacia (Acacia auriculiformis) are potential to be utilized as organic fertilizers. The objective of this research was to study the influence the addition of inoculation with Effective Microorganism-4 (EM-4) and molasses in composting process of angsana and acacia leaves. As much as 3 kilograms of acacia and angsana leaves crushed till 1 cm size was incorporated into fermentor tank. Into the reactor, EM-4 and molases were then added and the fermentor was sealed. This mixture was incubated for 4 weeks, and every 4 days it was homogenized by flipping the fermentor tank. Sampling was carried out every 7 days for total organic C and total N content measurements and C/N ratio calculation. The volume ratio of EM-4 inoculation and molasses addition was varied i.e. 3:3, 9:3, 3:9, and 9:9. The fastest maturity of organic fertilizer during the composting process was achieved by EM-4: molasses ratio of 3:9 which only needed 21 days composting time. All other ratios have reached maturity on the 28th day of composting process. The variation of EM-4 has an effect on the time of organic fertilizer maturity product, while the variation of molasses has no effect on the process. ABSTRAKSampah daun kering di lingkungan Universitas Sebelas Maret Surakarta (UNS) diperkirakan mencapai 8 kuintal per hari dan terdiri dari daun pohon angsana serta akasia. Jumlah sampah sebanyak ini sangat berpotensi untuk dimanfaatkan sebagai pupuk organik. Penelitian ini bertujuan untuk mempelajari pengaruh penambahan Effective Microorganism-4 (EM-4) dan molasses pada proses composting campuran daun angsana (Pterocarpus indicus) dan akasia (Acasia auriculiformis). Sebanyak 3 kg campuran cacahan daun angsana dan akasia yang berukuran sekitar 1 cm dimasukkan ke dalam tangki fermentasi. Lalu ditambah EM-4 dan molasses kemudian tangki ditutup rapat. Campuran ini diinkubasi selama 4 minggu dan setiap 4 hari dilakukan pengadukan dengan cara membolak-balik tangki fermentasi. Pengambilan sampel dilakukan setiap 7 hari untuk pemeriksaan kadar C organik dan N total serta penghitungan rasio C/N. Penambahan EM-4 dan molasses divariasikan dengan perbandingan EM-4:molasses sebesar 3:3, 9:3, 3:9, dan 9:9. Kematangan pupuk organik hasil composting paling cepat dicapai oleh rasio EM-4:molasses sebesar 3:9 yaitu pada hari ke-21 dan semua telah mencapai kematangan pada hari ke-28. Variasi EM-4 berpengaruh pada waktu kematangan produk pupuk organik, sedangkan variasi molasses tidak berpengaruh terhadap proses.
oai:jurnal.ugm.ac.id:article/23057
2018-05-10T01:28:41Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/23057
2018-05-10T01:28:41Z
Jurnal Rekayasa Proses
Vol 11, No 1 (2017); 12-18
Pengaruh Organic Loading Rate Pada Produksi Biohidrogen dari Sampah Buah Melon (Cucumis melo L.) Menggunakan Reaktor Alir Pipa
https://journal.ugm.ac.id/jrekpros/article/download/23057/54923
Nurkholis, Nurkholis; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Sarto, Sarto; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Hidayat, Muslikhin; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2017-08-02 20:45:06
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/23057
id
The energy crisis and adverse effects from the use of fossil fuels requires the development of energy sources that are non-polluting and renewable, such as bio-H2. Bio-H2 can be produced from organic biomass such as melon fruit waste, because it is available in large quantities and has adequate content of organic fraction. Production of bio-H2 from melon fruit waste done by dark fermentation on the pipe flow reactor consisting of microorganisms acclimatization phase and continuous substrate feeding phase with variation of organic loading rate (OLR) are 6.0443 kg VS/ m3.day (OLR1), 7.6217 kg VS/ m3.day (OLR2) and 26.3152 kg VS/ m3.day (OLR3). Gas and liquid samples taken from the reactor for analysis of H2 concentration, volatile solid (VS) and volatile fatty acid (VFA) The results of the study showed that the production of bio-H2 optimal amounted to 90.8904 mL/ g VS on variations OLR3 is 26.3152 kg VS/ m3.day with substrate degradation efficiency reached 45.39%. The concentration of organic acids produced ranges from 400-800 mg/ L and acetic acid as the dominant product with an average concentration of 442.9276 mg/ L. ABSTRAKKrisis energi dan dampak buruk dari penggunaan bahan bakar fosil menuntut pengembangan sumber energi yang bersifat non-polutif dan terbarukan, misalnya bio-H2. Bio-H2 dapat di produksi dari biomassa organik seperti sampah buah melon, karena terdapat dalam jumlah banyak dan memiliki kandungan fraksi organik yang memadai. Pada penelitian ini produksi bio-H2 dari sampah buah melon dilakukan secara fermentasi gelap pada reaktor alir pipa yang terdiri dari tahap aklimatisasi mikroorganisme dan tahap pengumpanan substrat secara kontinu. Variasi organic loading rate (OLR) yang digunakan adalah 6.04 kg VS/(m3.hari) (OLR-1), 7.62 kg VS/(m3.hari) (OLR-2) dan 26.32 kg VS/(m3.hari) (OLR-3). Sampel gas dan cairan diambil dari dalam reaktor untuk di analisis kadar H2, kadar volatile solid (VS) dan volatile fatty acid (VFA). Hasil penelitian menunjukkan bahwa produksi bio-H2 yang optimal sebesar 90.89 mL/g VS pada variasi OLR-3 yaitu 26.32 kg VS/(m3.hari) dengan efisiensi degradasi substrat mencapai 45.39%. Konsentrasi asam-asam organik yang dihasilkan berkisar antara 400-800 mg/L dan asam asetat adalah sebagai produk yang dominan dengan konsentrasi rata-rata sebesar 442.93 mg/L.
oai:jurnal.ugm.ac.id:article/23154
2018-05-10T01:28:41Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/23154
2018-05-10T01:28:41Z
Jurnal Rekayasa Proses
Vol 11, No 1 (2017); 1-11
Kombinasi Adsorben Biji Kelor - Zeolit Alam Lampung untuk Meningkatkan Efektivitas Penjerapan Logam Pb dalam Air secara Kontinu pada Kolom Fixed Bed Adsorber
Ginting, Simparmin Br; Jurusan Teknik Kimia, Fakultas Teknik, Universitas Lampung
Syukur, Sebastian Djoni; Jurusan Teknik Kimia, Fakultas Teknik, Universitas Lampung
Yulia, Yeni; Jurusan Teknik Kimia, Fakultas Teknik, Universitas Lampung
2017-08-02 20:44:48
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/23154
id
The mixture of adsorbents of moringa seed (BK) and natural zeolite of Lampung (ZAL) is placed in a fixed bed adsorber column arranged at a certain height according to the designed height ratio. BK is processed by extraction to remove its oil content while ZAL is activated by chemical and physical treatments. Composition ratio of BK-ZAL (cm/cm) was varied i.e.1:1, 1:2 and 1:3 and concentrations of Pb entering adsorber were 1 ppm and 2 ppm. The adsorption conditions were 20-35 mesh adsorbent size, 4 cm diameter column of adsorber, 5 cm bed height, and 8 liters/3 hours flowrate. Upflow adsorption was performed in a fixed bed adsorption column for 3 hours and Pb solution of output adsorber was taken at every 30 minutes. Analysis of Pb content was performed by Atomic Absorption Spectroscopy (AAS). Adsorbent BK before and after extracted, and after adsorption were characterized using Fourier Transmission Infra Red (FTIR). ZAL before and after activation were characterized using X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), and Fourier Transmission Infra Red (FTIR). The characterization results of XRD, XRF and FTIR showed that the crystalline phases of ZAL increased, the activation process of ZAL only caused a shift in the peak, no significant change in the structure of solids, and the content of impurities in ZAL reduced after activation, thereby enhancing its ability to adsorb Pb. AAS analysis results showed that the best combination adsorbent BK-ZAL (cm/cm) was 1: 2 with the highest effectiveness of the entrapment of Pb metal reached 99.90%. The adsorption capacity of adsorbent was 2.25 mg Pb/ gram adsorbent calculated using Freundlich equilibrium model. ABSTRAKKombinasi adsorben yang terdiri dari biji kelor (BK) dan zeolit alam Lampung (ZAL) ditempatkan di dalam kolom adsorber unggun tetap yang disusun pada ketinggian tertentu sesuai rasio tinggi yang dirancang. Adsorben BK diekstraksi untuk mengeluarkan kandungan minyaknya dan ZAL diaktivasi secara kimia dan fisika. Variasi rasio tinggi komposisi BK-ZAL (cm/cm) di dalam kolom dilakukan pada kisaran 1:1, 1:2, dan 1:3. Variasi konsentrasi larutan Pb masuk adsorber adalah 1 ppm dan 2 ppm. Ukuran partikel adsorben yang digunakan sebesar 20-35 mesh, diameter kolom adsorpsi 4 cm, tinggi unggun 5 cm, dan laju alir larutan Pb 8 liter per 3 jam. Proses adsorpsi dilakukan secara upflow pada kolom adsorpsi dengan unggun tetap selama 3 jam dan larutan Pb keluaran adsorber diambil setiap 30 menit untuk dianalisis dengan Atomic Absorption Spectroscopy (AAS). Adsorben BK sebelum dan setelah diekstrak, serta setelah proses adsorpsi dikarakterisasi menggunakan Fourier Transmission Infra Red (FTIR). Adsorben ZAL sebelum dan setelah diaktivasi dikarakterisasi menggunakan X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), dan Fourier Transmission Infra Red (FTIR). Hasil karakterisasi XRD, XRF, dan FTIR menunjukkan bahwa fase kristalin ZAL bertambah, proses aktivasi ZAL hanya menyebabkan pergeseran puncak yang muncul, tidak terjadi perubahan struktur padatan secara signifikan, dan kandungan zat pengotor pada ZAL turun setelah diaktivasi sehingga meningkatkan kemampuan untuk menjerap logam Pb. Hasil analisis AAS menunjukkan kombinasi adsorben BK-ZAL (cm/cm) terbaik yaitu 1:2 dengan efektivitas penjerapan logam Pb tertinggi mencapai 99.90%. Hasil perhitungan kapasitas adsorpsi adsorben adalah 2.25 mg Pb/ gram adsorben yang dihitung dengan menggunakan persamaan adsorpsi Freunlich.
oai:jurnal.ugm.ac.id:article/23321
2018-05-10T01:28:41Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/23321
2018-05-10T01:28:41Z
Jurnal Rekayasa Proses
Vol 11, No 1 (2017); 30-35
Uji Validitas Model Shrinking Core terhadap Pengaruh Konsentrasi Asam Sitrat dalam Proses Leaching Nikel Laterit
Wanta, Kevin Cleary; Program Studi Teknik Kimia, Fakultas Teknologi Industri, Universitas Katolik Parahyangan
Petrus, Himawan TBM; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Perdana, Indra; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Astuti, Widi; Balai Penelitian Teknologi Material, Lembaga Ilmu Pengetahuan Indonesia
2017-08-02 20:45:09
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/23321
id
Atmospheric pressure acid leaching process is one of nickel laterite processing which has a big potential to be applied in industry. The leaching process is influenced by several factors and one of them is concentration of acid as leachant. The purpose of this present study is to learn the effect of concentration of citric acid on the use of shrinking core kinetic model. The process was done by varying citric acid concentration at 0.1, 1, and 2 M. The other operation conditions, such as particle size, solid-liquid ratio, temperature, stirring speed, and leaching process were kept constant at 125-150 μm, 0,2 sample mass/volume of acid solution, 85 oC, 200 rpm, and 120 minutes, respectively. The experimental results showed that the higher concentration of citric acid was used, the higher the percentage recovery of nickel was obtained. In addition, the validity test of shrinking core model indicated a positive impact to describe physical phenomenon of leaching process.ABSTRAKProses atmospheric pressure acid leaching merupakan salah satu proses pengolahan nikel laterit yang berpotensi untuk diaplikasikan dalam skala industri. Proses leaching ini dipengaruhi oleh beberapa faktor, diantaranya konsentrasi asam sebagai leachant. Studi ini dilakukan dengan tujuan untuk mempelajari pengaruh konsentrasi asam sitrat terhadap penggunaan model kinetika shrinking core dalam proses leaching nikel laterit. Proses leaching dilakukan dengan memvariasikan konsentrasi asam sitrat sebesar 0,1; 1,0, dan 2,0 M. Kondisi operasi lainnya, seperti ukuran partikel, rasio padat-cair, suhu, kecepatan pengadukan, dan lama proses dijaga konstan pada 125-150 μm, 0,2 massa sampel/volume larutan asam, 85 oC, 200 rpm, dan 120 menit, secara berurutan. Hasil percobaan menunjukkan bahwa semakin tinggi konsentrasi asam sitrat yang digunakan, maka semakin tinggi pula nilai persentase recovery nikel yang diperoleh. Selain itu, uji validitas model shrinking core terhadap data percobaan menunjukkan dampak yang positif dalam mendeskripsikan fenomena fisis proses leaching.
oai:jurnal.ugm.ac.id:article/24523
2017-10-10T01:13:11Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/24523
2017-10-10T01:13:11Z
Jurnal Rekayasa Proses
Vol 9, No 1 (2015); 1-8
Pemodelan Dinamika Awal Adsorpsi Na2S dalam Kolom Bahan Isian Biji Salak (Salacca Zalacca)
Sari, Irma Atika; Program Studi Teknik Kimia, Fakultas Teknologi Industri, Universitas Ahmad Dahlan; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Azis, Muhammad Mufti; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Syamsiah, Siti; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Sutijan, Sutijan; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
2015-05-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/24523
Biofiltration is a promising method for gas purification due to its efficiency and low operating cost. One way to utilize biofiltration is in biogas purification where H2S is removed from the biogas product. The presence of H2S may cause severe corrosion in biogas processing facilities. By the use of biofilter, H2S is dissolved and adsorbed on packing material. This study investigated the adsorption process that occured during the beginning of biofilter operation. Na2S has been used as a model compound for H2S with packing material from snake fruit seeds. In this study, we have investigated the influence of liquid flowrate and inlet concentration of Na2S solutions. Na2S solution was fed from the top part of the column and trickled down through the snake fruit seed bed. The dissolved sulfide left the column from the bottom part which was then collected in a sample bottle and analized periodically with UV-VIS spectrophotometer. A one dimensional mathematical model of the adsorption column with respect to z direction was proposed to describe the adsorption behavior. In addition, Freundlich isotherm was used to describe the solid-liquid adsorption equilibrium. The experimental results showed that low flowrates i.e. 1.59 and 2.97 mL/s gave larger adsorption capacities than higher flowrate i.e. 3.96 and 5.58 mL/s. In addition, the influence of inlet concentrations to the breakthrough characteristics were found to be negligible. The fitting results estimated the values of DL=1.3174.10-7 m2/s, α=1.002.10-4 and n=12.661. As a result, it could be concluded that the axial diffusion had small influence on the adsorption of Na2S solution. In addition, the small value of α as well as large value of n indicated that the adsorption capacity of snake fruit seeds was relatively small. Keywords : snake fruit seed, biofiltration, adsorption, adsorption equilibrium, Na2S, sulfide Biofiltrasi adalah teknologi yang menjanjikan dalam pemurnian gas karena efisiensi yang tinggi serta biaya operasi yang rendah. Salah satu pemanfaatan biofiltrasi yang cukup menjanjikan adalah pemurnian biogas dimana gas H2S dipisahkan dari produk biogas akhir. Keberadaan gas H2S pada biogas dapat menyebabkan korosi pada peralatan pemrosesan biogas. Dalam biofilter, H2S akan terlarut dan kemudian akan teradsorpsi pada bahan isian. Penelitian ini mempelajari proses adsorpsi yang terjadi di awal proses biofiltrasi terhadap sulfida terlarut. Disini, larutan Na2S telah digunakan sebagai komponen model H2S untuk dijerap dengan bahan isian biji salak. Variabel proses yang dipelajari adalah variasi laju alir cairan dan variasi konsentrasi input larutan Na2S. Larutan Na2S dilewatkan pada kolom biofiltrasi dari atas melewati bahan isian biji salak, kemudian sulfida terlarut yang keluar pada kolom bawah ditampung dalam botol sampel dan dianalisis pada berbagai waktu dengan menggunakan UV-VIS spektrofotometer. Pemodelan matematika proses adsorpsi telah disusun dengan model adsorpsi 1 dimensi ke arah z. Persamaan kesetimbangan yang digunakan menggunakan persamaan kesetimbangan Freundlich. Hasil percobaan menunjukkan bahwa dengan debit aliran yang kecil seperti 1,59 dan 2,97 mL/det didapatkan penjerapan yang lebih besar jika dibandingkan dengan debit aliran besar seperti 3,96 dan 5,58 mL/det. Sementara itu, pengaruh konsentrasi umpan terhadap karakteristik kurva breakthrough relatif kecil. Hasil fitting memberikan nilai DL=1,3174.10-7 m2/s, α=1,002.10-4 dan n=12,661. Dengan demikian, secara umum dapat disimpulkan bahwa difusi longitudinal pada kolom adsorpsi berperan kecil terhadap proses adsorpsi sulfida. Sedangkan nilai α yang kecil serta n yang besar pada persamaan Freundlich menunjukkan kapasitas penjerapan biji salak yang relatif kecil. Kata kunci: biji salak, biofiltrasi, adsorpsi, kesetimbangan adsorpsi, Na2S, sulfide
oai:jurnal.ugm.ac.id:article/24524
2017-04-28T01:03:55Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/24524
2017-04-28T01:03:55Z
Jurnal Rekayasa Proses
Vol 9, No 1 (2015); 9-15
Karakterisasi Larutan Polimer KYPAM HPAM untuk Bahan Injeksi dalam Enhanced Oil Recovery (EOR)
Wicaksono, Harimurti
Sutijan,
Yuliansyah, Ahmad Tawfiequrrahman
2015-05-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/24524
Polymer injection is one method of Enhanced Oil Recovery (EOR), where the polymer is dissolved in water, usually the formation water. Hydrolyzed polyacrylamide (HPAM) polymer types are most commonly used. This study aims to investigate the effect of KYPAM HPAM polymer concentration and operating conditions upon the water injection in order to determine the optimal injection system. Viscosity of polyacrylamide solution was measured with a Brookfield viscometer. Variation in salinity is carried out by mixing formation water with distilled water, whereas for high salinity of formation water using evaporation method. Shear rate was varied in the range of 145 s-1, while solution temperature was varied in the range of 70 87°C , and the effect of H2S gas in the solution was conducted by saturating the solution using natural gas which has concentration of H2S as 100 ppm.
The results show that the effect of salinity solution has the greatest influence on the decrease in viscosity of the solution when compared to the other factors. Decrease in viscosity was due to agglomeration process resulting precipitate of polyacrylamide in the form of vaterite and aragonite morphology. The result also show that an increase in shear rate resulting lower viscosity. The increase in temperature causes the viscosity of the solution decreases. Meanwhile, the presence of H2S in the solution reduces the viscosity of the solution due to chemical degradation.
Keywords: EOR, formation water, polymer injection, hydrolyzed polyacrylamide, salinity, polymer concentration.
Injeksi polimer merupakan salah satu metode dalam Enhanced Oil Recovery (EOR). Dalam hal ini, polimer terlebih dulu dilarutkan dalam air, biasanya air formasi. Poliakrilamida terhidrolisis (HPAM) merupakan salah satu jenis polimer yang paling sering digunakan. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi polimer KYPAM HPAM dan kondisi operasi pada injeksi air untuk menentukan sistem injeksi yang optimal. Larutan poliakrilamida diukur viskositasnya dengan viskometer Brookfield. Variasi salinitas dilakukan dengan mencampur air formasi dan aquades, sedangkan untuk salinitas tinggi dari air formasi dengan menggunakan metode penguapan.Variasi shear rate dilakukan pada kisaran 145 s-1, sedangkan suhu larutan divariasikan di kisaran 7087°C. Pengaruh gas H2S dalam larutan dilakukan dengan menjenuhkan larutan menggunakan gas alam yang memiliki konsentrasi H2S 100 ppm.
Hasil penelitian menunjukkan bahwa salinitas memiliki pengaruh terbesar pada penurunan viskositas larutan bila dibandingkan dengan faktor-faktor lain. Penurunan viskositas disebabkan aglomerasi menghasilkan endapan poliakrilamida dalam bentuk vaterite dan morfologi aragonit. Hasil percobaan juga menunjukkan bahwa peningkatan shear rate, mengakibatkan viskositas larutan terukur rendah. Peningkatan suhu menyebabkan viskositas larutan turun, sedangkan kehadiran H2S dalam larutan mengurangi viskositas larutan karena terjadi degradasi kimia pada polimer.
Kata kunci: EOR, air formasi, injeksi polimer, hydrolyzed polyacrylamide, salinitas, konsentrasi polimer
oai:jurnal.ugm.ac.id:article/24525
2017-10-10T01:21:34Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/24525
2017-10-10T01:21:34Z
Jurnal Rekayasa Proses
Vol 9, No 1 (2015); 16-21
Optimasi dan Pemodelan Matematis Deasetilasi Kitin Menjadi Kitosan Menggunakan KOH
Safitra, Edwin Rizki; Jurusan Teknik Kimia, Fakultas Teknik Universitas Lampung
Budhijanto, Budhijanto; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Rochmadi, Rochmadi; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
2015-05-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/24525
Chitosan is valuable product that can be produced from crustacean shell wastes. Chitosan is important ingredient in various fields, for example food industry, biotechnology, pharmacy, medicine, and environment. The objective of this experiment was to obtain optimum conditions of chitin deacetylation process and to propose mathematical model of deacetylation reaction to be used in reactor design. This experiment used KOH solution at various concentration of 40 to 70% (weight fraction), temperature of 80 to 120oC, and reaction time of 4-6 hours. The results showed that optimum condition was achieved at the concentration of KOH of 60%, temperature of 100oC, and reaction time of 5.5 hours. At that condition, the degree of deacetylation (DD) of the chitosan produced was 80.79%, which well met the market standard of 80% DD. The mathematical model proposed in this study indicated that diffusion controlled the the overall rate of reaction. Keywords: chitin, chitosan, degree of deacetylation, optimization, mathematical modeling. Pemanfaatan limbah padat udang sudah sangat lama dikembangkan oleh para peneliti. Salah satu produk yang dapat dihasilkan dari limbah kulit udang adalah kitosan. Tercatat 200 kegunaan kitosan di berbagai bidang dari industri pangan, bioteknologi, farmasi, kedokteran, serta lingkungan. Penelitian ini bertujuan untuk mendapatkan kondisi optimum proses deasetilasi kitin dan merumuskan model matematis reaksi deasetilasi untuk keperluan perancangan reaktor. Pada penelitian ini digunakan larutan KOH dengan variasi konsentrasi 40-70% (% berat), suhu 80-120oC, dan waktu reaksi 4-6 jam. Kondisi optimum penelitian ini dicapai pada suhu 100oC, waktu reaksi 5,5 jam, dan konsentrasi KOH 60%. Pada kondisi tersebut, diperoleh kitosan dengan nilai derajat deasetilasi (DD) 80,79% dan sudah sesuai dengan permintaan pasar (minimal 80%). Model matematis yang diperoleh pada penelitian ini mengindikasikan bahwa dalam proses produksi kitosan dari limbah kulit udang, proses transfer massa (difusi) lebih mengontrol dibandingkan reaksi. Kata kunci: kitin, kitosan, derajat deasetilasi, optimasi, pemodelan matematis.
oai:jurnal.ugm.ac.id:article/24526
2017-04-28T01:03:55Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/24526
2017-04-28T01:03:55Z
Jurnal Rekayasa Proses
Vol 9, No 1 (2015); 22-27
Pengaruh Kadar Air Umpan dan Rasio C/N pada Produksi Biogas dari Sampah Organik Pasar
Zuliyana,
Wirawan, Sang Kompiang
Budhijanto, Wiratni
Cahyono, Rochim Bakti
2015-05-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/24526
Nowadays, Indonesia is facing serious problem related to the rapid generation of municipal solid waste (MSW) and dependence on fossil energy. Converting organic content of MSW into biogas through biological process by mean of anaerobic digester is one of promising proposals to solve the MSW problem. In order to optimize biogas production, this research studies the effect of Total Solid (TS) content and ratio of carbon to nitrogen (C/N) within organic fraction of MSW as raw material for biogas production. The organic fraction of MSW consists of vegetables and fruits waste which originated from traditional market.
The experiments using various TS concentrations (10%, 15% and 20%) were conducted in batch reactors. The results showed that TS content of MSW raw material had significant effects on the total volume and CH4 concentration of biogas production. High water content in MSW raw material enhanced the hydrolysis of organic fraction as well as avoided the excessive Volatile Fatty Acid (VFA) concentration which posed the risk of inhibition on the anaerobic process. Based on the results, the TS concentration of 10-15% in the organic MSW would offer an optimum yield of biogas production. In order to examine the effect of C/N ratio, the organic MSW was modified using ZA fertilizer (36, 30, 20 and 10 C/N ratios). The C/N ratios of 20-30 produced high amount biogas and CH4 concentration compared to others. The C/N ratio should be maintained at the optimum value to prevent the accumulation of free ammonia which could cause problems in the anaerobic process.
Based on the results, the biogas production from organic MSW would yield the optimum biogas amount and CH4 concentration when the TS concentration and C/N ratio were 10-15% and 20-30, respectively. This outcome would give recommendation on the water addition to the raw organic fraction of MSW and C/N modification when converting the organic fraction of MSW to biogas.
Keywords: biogas, C/N ratio, municipal solid waste, total solid.
Permasalahan sampah dan ketergantungan akan energi fosil mendorong pemanfaatan sampah organik menjadi biogas. Penelitian ini dilakukan untuk mempelajari pengaruh konsentrasi Total Solid (TS) dan rasio C/N dari sampah kota sebagai bahan baku produksi biogas. Sampah kota berupa sayuran dan buah yang merupakan fraksi organik yang diperoleh dari pasar tradisional dan selanjutnya produksi biogas dilakukan dalam reaktor batch.
Konsentrasi TS bahan baku divariasikan menjadi tiga variasi nilai TS yaitu 20%, 15% dan 10%. Konsentrasi TS pada bahan baku digester berpengaruh secara signifikan terhadap jumlah akumulatif biogas yang dihasilkan dan kadar CH4. Diperlukan air dengan jumlah yang optimum untuk mempercepat proses hidrolisis sekaligus mencegah konsentrasi Volatile Fatty Acid (VFA) terlalu tinggi yang beresiko inhibitor dalam sistem anaerob. Pada penelitian ini, untuk jenis sampah sayur/buah, nilai TS yang relatif baik adalah antara 10-15%. Modifikasi nilai rasio karbon terhadap nitrogen (C/N) dilakukan pada bahan baku dengan kadar TS optimum dimana nilai rasio C/N dimodifikasi menjadi 36 (rasio C/N orisinal TS optimum), 30, 20 dan 10. C/N ratio yang lebih rendah daripada nilai orisinalnya dicapai dengan penambahan pupuk ZA. Dalam penelitian ini, rasio C/N antara 20-30 memberikan hasil yang relatif paling baik dibandingkan nilai rasio C/N yang lain. Perlu dijaga agar nilai rasio C/N tidak terlalu rendah yang menyebabkan kinerja sistem anaerob justru lebih buruk. karena akumulasi ammonia bebas yang justru merupakan inhibitor.
Berdasarkan hasil yang diperoleh, produksi biogas dari sampah buah dan sayur menunjukkan hasil yang optimum saat kisaran konsentrasi TS 10-15% dan rasio C/N 20-30. Hal ini memberikan rekomendasi jumlah penambahan air dan perlu tidaknya koreksi rasio C/N pada umpan bahan baku saat operasi skala industri.
Kata kunci: biogas, rasio C/N, sampah kota, total solid.
oai:jurnal.ugm.ac.id:article/24527
2017-10-10T01:24:13Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/24527
2017-10-10T01:24:13Z
Jurnal Rekayasa Proses
Vol 9, No 1 (2015); 28-35
Pengaruh Konsentrasi Polifenol pada Produksi Asam Laktat dari Substrat Menggunakan Rhizopus oryzae
Nugraha, Maulana Gilar; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Syamsiah, Siti; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
Prasetya, Agus; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
2015-05-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/24527
Polyphenol is antioxidant compound naturally present in plants e.g in cacao shell (Thebrema cacao L.). The cacao shell has high cellulose content (30-50%), and therefore it is potential to be converted into various types of products. Cellulose could be hydrolyzed to produce glucose, and glucose could be fermented to become lactic acid. However, polyphenol presence in the cacao shell is suspected to be inhibitory to fermentation process. This research aimed to figure out the polyphenol effect in lactic acid fermentation with glucose as substrate by the fungus Rhizopus oryzae. Polyphenol concentrations in the fermentation broth were varied with value of 0, 10, 15, and 20 g/L. Along the course of the experiment, lactic acid concentration was measured by means of gravimetric and conductometric method. Fungus growth was measured through dry mass method while consumption of glucose was observed by glucose determination with Nelson-Samogyi method. The results showed that polyphenol presence in fermentation system would decrease lactic acid production from 40.55 g/L (system without polyphenol) to 18.24 g/L (system with 20 g/L polyphenol). Microbe growth inhibition also observed from 3.68 g/L (system without polyphenol) to 0.51 g/L (system with 20 g/L polyphenol). However, polyphenol presence did not affect the total glucose consumption. Final glucose concentrations in all system were about 10.94 to 19.28 g/L. Some possible factors for this phenomenon were glucose conversion to another product and glucose utilization for cell maintenance. This research also found that the best kinetic model to represent the fermentation system was uncompetitive inhibition model. Keywords: fermentation kinetics, inhibitor, polyphenol, cacao Kulit buah cokelat (Theobrema cacao L.) merupakan salah satu limbah perkebunan dengan kandungan selulosa yang relatif tinggi (30-50%) yang berpotensi sebagai bahan baku berbagai produk. Selain itu, kulit buah cokelat juga mengandung polifenol sebagai antioksidan dalam jumlah yang relative besar. Selulosa dapat dihidrolisis menjadi glukosa dan hasil hidrolisis tersebut dapat difermentasi menjadi asam laktat. Namun keberadaan polifenol dalam kulit kakao berpotensi menghambat proses fermentasi selulosa. Penelitian ini bertujuan untuk mempelajari pengaruh polifenol terhadap fermentasi asam laktat dengan bahan baku glukosa menggunakan Rhizopus oryzae. Variasi konsentrasi polifenol yang digunakan adalah 0, 10, 15, dan 20 g/L dalam cairan fermentasi. Sepanjang penelitian konsentrasi asam laktat dianalisis dengan metode gravimetri dan konduktometri. Konsentrasi mikroba diukur dengan menggunakan metode berat kering sedangkan pengukuran konsentrasi glukosa menggunakan metode Nelson-Samogyi. Hasil penelitian menunjukkan bahwa semakin tinggi konsentrasi polifenol dapat menurunkan produksi asam laktat dari 40,55 g/L (sistem tanpa polifenol) menjadi 18,24 g/L (sistem dengan 20 g/L polifenol). Pertumbuhan mikroba pun mengalami penurunan dari 3,68 g/L (sistem tanpa polifenol) menjadi 0,51 g/L (sistem dengan 20 g/L polifenol). Walaupun demikian, konsumsi glukosa tidak terlalu dipengaruhi oleh penambahan polifenol. Nilai konsentrasi akhir glukosa sistem pada berbagai variasi polifenol berkisar 10,94 s/d 19,28 g/L. Hal ini kemungkinan disebabkan oleh terkonversinya glukosa menjadi produk samping lain dan alokasi untuk maintenance sel. Penelitian ini menyimpulkan bahwa model kinetika yang dapat merepresentasikan sistem ini dengan baik adalah model uncompetitive inhibition. Kata kunci: kinetika fermentasi, inhibitor, polifenol, kakao
oai:jurnal.ugm.ac.id:article/24868
2018-05-10T01:28:41Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/24868
2018-05-10T01:28:41Z
Jurnal Rekayasa Proses
Vol 11, No 1 (2017); 24-29
Pengaruh Rasio Doxorubisin:Apoferritin terhadap Kapasitas dan Efisiensi Enkapsulasi Doksorubisin dalam Apoferritin
Wiwoho, Novita; Sekolah Tinggi Teknologi Nuklir
Prihatiningsih, Maria Christina; Sekolah Tinggi Teknologi Nuklir-BATAN, Babarsari, Yogyakarta
Mujamilah, Mujamilah; Pusat Sains dan Teknologi Bahan Maju-BATAN, Kawasan Puspiptek Serpong, Tangerang Selatan
Sulungbudi, Grace Tj.; Pusat Sains dan Teknologi Bahan Maju-BATAN, Kawasan Puspiptek Serpong, Tangerang Selatan
2017-08-02 20:45:08
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/24868
id
Doxorubicin is a chemotherapy drug which is very toxic and causes many side effects. To reduce side effects, doxorubicin can be encapsulated by apoferritin into apoferritin doxorubicin (Apo-Dox) system. In this research, various mass of doxorubicin i.e. 0.17 mg (S1), 0.26 mg (S2), 0.35 mg (S3), and 0.52 mg (S4) were encapsulated with 21.50 mg apoferritin. Encapsulation process was carried out by lowering pH medium for apoferritin dis-assembly, doxorubicin addition and dialysis for gradual and controlled pH-increase of medium to support re-assembly of apoferritin and doxorubicin encapsulation. End-result samples were then centrifuged and washed to separate the unreacted doxorubicin and apoferritin’s subunits. Doxorubicin encapsulation efficiency was determined using microplate reader spectrophotometry. The highest encapsulation capasity was 3.87 g dox/mg apo for S4 samples. Increasing the weight of doxorubicin gives more significant effect on increasing the reactive weight of apoferritin, which reached 93.73% (S4 sample). Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) analysis confirm that apoferritin is in the Apo-Dox sample. ABSTRAKDoksorubisin merupakan obat kemoterapi yang sangat toksik dan menimbulkan berbagai efek samping. Untuk mengurangi efek samping tersebut, doksorubisin dapat dibungkus dengan protein apoferritin menjadi Apoferritin-Doksorubisin (Apo-Dox). Dalam penelitian ini, doksorubisin dengan berat 0,174 mg (S1), 0,261 mg (S2), 0,349 mg (S3), dan 0,523 mg (S4) dienkapsulasi apoferritin dengan berat 21,487 mg. Proses enkapsulasi dilakukan dengan mengubah pH larutan melalui penambahan glisin asetat, tris base, dan dialisa dalam tris asetat. Larutan di centrifuge dan di cuci untuk menghilangkan doksorubisin dan sub-unit apoferritin yang tidak bereaksi. Konsentrasi doksorubisin yang terenkapsulasi dalam apoferritin (μg dox/mg apo) ditentukan menggunakan microplate reader spectrophotometry. Konsentrasi cenderung mencapai optimum mulai sampel S2 dan hanya sedikit meningkat untuk sampel S3 dan S4 dengan nilai maksimum pada S4 sebesar 3,87 μg dox/mg apo. Peningkatan jumlah doksorubisin akan meningkatkan jumlah apoferritin yang bereaksi, dan diperoleh nilai efisiensi reaksi apoferritin tertinggi 93,73% untuk sampel S4. SDS-PAGE membuktikan bahwa apoferritin berada pada sampel Apo-Dox.
oai:jurnal.ugm.ac.id:article/26353
2018-05-10T01:28:41Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/26353
2018-05-10T01:28:41Z
Jurnal Rekayasa Proses
Vol 11, No 1 (2017); 36-42
Pengaruh Penambahan Zeolit Alam Termodifikasi sebagai Media Imobilisasi Bakteri terhadap Dekompisisi Material Organik secara Anaerob
Mellyanawaty, Melly; Program Studi Teknik Lingkungan, Fakultas Teknik, Universitas Muhammadiyah Tasikmalaya
Purnomo, Chandra Wahyu; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Budhijanto, Wiratni; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2017-08-02 20:45:31
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/26353
Environmental Engineering
Anaerobic digestion; distillery spent wash; impregnasi Fe; media imobilisasi; zeolit.
id-ID
This study aims to determine the effect of modified natural zeolite as microbial immobilization medium for anaerobic decomposition of organic materials. The modification was Fe2+ impregnation into the ring-shaped zeolite. Three different concentrations of Fe2+ solution were used to impregnate the zeolite, i.e. 10 mg/L, 100 mg/L and 2000 mg/L. The wet impregnation process was conducted. Four variations of Fe2+ concentration deposited into zeolite were prepared, i.e. 0 mgFe2+/gZeo (as control), 0.0016 mgFe2+/gZeo, 0.0156 mgFe2+/gZeo and 0.3125 mgFe2+/gZeo. The modified zeolite was added to the batch anaerobic reactor, which filled with the volume ratio of liquid substrate and zeolite of 1:1 for all variations of media. Distillery spent wash was used as the substrate in this study. The soluble Chemical Oxygen Demand (sCOD) value of the substrate was homogenized at 10000 mg/L. Effluent digester of cow manure bio digester was added as inoculum. The volume ratio of distillery spent wash to the inoculum was 2:1. The anaerobic process was conducted for 28 days.The performance of four media in the anaerobic digestion of distillation spent wash was measured in terms of sCOD, total solid (TS), and volatile solid (VS). The comparison among media was more accurately and conclusively represented by sCOD value. The visual analysis of sCOD trend during 28 days indicated that zeolite with 0.0156 mgFe/gZeo resulted in the highest sCOD removal of 66.73%. Meanwhile, zeolite with 0.3125 mgFe/gZeo increased the production of biogas by the highest percentage of 43% to be compared to control. Generally speaking, the addition of Fe2+ into zeolit led to higher removal of sCOD and produced more biogas than control.ABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh penambahan zeolit alam termodifikasi sebagai media imobilisasi terhadap dekomposisi material organik pada proses anaerobic digestion. Modifikasi yang dilakukan adalah dengan cara mengimpregnasi ion besi(Fe2+)ke dalam zeolit yang telah dibentuk menjadi cincin Raschig. Impregnasi yang dilakukan adalah impregnasi basah. Dalam penelitian ini digunakan 3 variasi konsentrasi larutan Fe2+ yaitu 10 mg/L; 100 mg/L dan 2000 mg/L. Dari hasil impregnasi zeolit menggunakan ketiga konsentrasi tersebut diperoleh kadar Fe2+ yang terdeposit ke dalam zeolit berturut-turut: 0,0016 mgFe2+/gZeo; 0,0156 mgFe2+/gZeo; 0,3125 mgFe2+/gZeo dan 0 mgFe2+/gZeo digunakan sebagai kontrol. Zeolit termodifikasi Fe2+ kemudian ditambahkan ke dalam reaktor anaerobik yang dijalankan secara batch. Perbandingan volume media zeolit dan cairan adalah 1:1. Substrat yang digunakan berupa campuran limbah distillery spent wash dengan konsentrasi soluble Chemical Oxygen Demand (sCOD) 10.000 mg/L dan keluaran dari digester aktif kotoran sapi sebagai inokulum. Perbandingan volume distillery spent wash terhadap inokulum sebesar 2:1. Proses anaerobik dijalankan selama 28 hari. Jika dibandingkan dengan data Total Solid (TS) dan Volatile Solid (VS), hasil percobaan menunjukkan bahwa data analisis sCOD memberikan data yang lebih akurat dan konklusif untuk mengukur perubahan material organik dalam proses peruraian anaerobik menggunakan media imobilisasi. Dari keempat variasi kadar Fe2+ yang digunakan dalam penelitian ini, Fe2+ dengan kadar 0,0156 mgFe/gZeo memberikan efisiensi penurunan material organik (sCOD) tertinggi yaitu 66,73%. Sedangkan Fe2+ dengan kadar 0,3125 mgFe/gZeo mampu meningkatkan produksi biogas sebesar 43%. Namun secara keseluruhan proses peruraian anaerobik yang menggunakan zeolit termodifikasi Fe2+ menghasilkan biogas lebih banyak daripada kontrol (zeolit tanpa Fe2+).
oai:jurnal.ugm.ac.id:article/26900
2018-09-04T01:16:57Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/26900
2018-09-04T01:16:57Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 78-85
Pengurangan Zat Warna Remazol Red Rb Menggunakan Metode Elektrokoagulasi Secara Batch
Setianingrum, Novie Putri
Prasetya, Agus; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Sarto, Sarto; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2018-01-23 07:33:29
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/26900
id
Batik is one of the distinctive cultural chacteristic of the Indonesian national that has gained recognition from UNESCO. Batik industries have grown rapidly. However, the activity industry produces liquid, especially from batik’s dyeing processes.. The conventional method which is used for processing wastewater still has limitation so that an innovation method wastewater treatment is need for example electrocoagulation. Electrocoagulation is a process of coagulation using unidirectional electrics current through electro-chemical process. In this work, electrocoagulation was employed to treat wastewater (synthetic dyes remazol red (Rb) as wastewater model). The method was carried out by varying the distance between electrode distance and electrical voltage. Variation of distance between electrode range were 2 cm and 3 cm while variation of electrical voltage range were 10 volt and 15 volt. To determine the effect of electrode distance and electrical voltage on treatsment performances the chemical oxygen demand(COD), total suspended solid (TSS) and waste color. The samples were taken at 10 minutes, 20 minutes, 40 minutes and 60 minutes during the process. The results showed that the distance of the electrode and the voltage affected to thr reduction of COD, TSS and waste color. The optimum elecrode distance and voltage in this research were 2 cm and 10 volt. The research showed the decrease in COD concentration from 428 mg/L to 54 mg/L, TSS concentration from 850 mg/L to 277 mg/L and the decrease in waste color from 2733 PtCo to 75,5 PtCo. ABSTRAKBatik merupakan salah satu ciri budaya khas bangsa Indonesia yang telah mendapatkan pengakuan dari UNESCO. Industri batik mengalami pertumbuhan cukup pesat. Aktivitas produksi dalam industri semakin meningkat menyebabkan limbah cair terutama dari proses pewarnaan semakin banyak. Metode konvensional untuk pengolahan limbah cair masih memiliki kekurangan sehingga memerluka metode pengolahan limbah alternatif, yaitu metode elektrokoagulasi. Proses elektrokoagulasi merupakan suatu proses koagulasi dengan menggunakan arus listrik searah melalui proses elektrokimia. Proses elektrokoagulasi dilakukan dengan memvariasikan tegangan listrik dan jarak antar elektroda yaitu 10 volt dan 15 volt serta 2 cm dan 3 cm. Untuk mengetahui pengaruh tegangan listrik dan jarak antar elektroda maka dilakukan pengukuran COD, TSS dan Warna dimana sampel diambil setiap 10 menit, 20 menit, 40 menit dan 60 menit lalu dianalisis. Hasil penelitian menunjukkan bahwa tegangan listrik dan jarak antar elektroda memberikan pengaruh terhadap penurunan COD, TSS dan Warna pada limbah cair sintetis Remazol Red RB. Jarak antar elektroda dan tegangan listrik yang optimum pada penelitian ini yaitu 2 cm dan 10 volt dengan penurunan konsentrasi COD yang pada awalnya 428 mg/L menjadi 54 mg/L, penurunan TSS yang pada awalnya 850 mg/L menjadi 277 mg/L dan penurunan Warna yang pada awalnya sebesar 2733 PtCo menjadi 75,5 PtCo.
oai:jurnal.ugm.ac.id:article/26933
2018-09-04T01:01:51Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/26933
2018-09-04T01:01:51Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 43-53
Komputasi Dinamika Fluida pada T-Mikro Mixer
https://journal.ugm.ac.id/jrekpros/article/download/26933/56952
Ramadhany, Putri; Universitas Katolik Parahyangan
2018-01-23 07:33:31
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/26933
id
Fluid diffusion can occur effectively if a high gradient concentration exists in every part of the fluid. This can be achieved by decreasing the cross section area of the channel into micro size. The miniatur size of micro mixer can be very effective for molecular diffusion in the mixing process. In this research, the modeling of mixing and heat transfer in the passive micro mixer was conducted. T-shaped mixer was chosen as micro mixer. Water was used as medium and passive tracers were added to differentiate water profile from two different inlets. Mixing and heat transfer profiles inside the T-micro mixer were observed. The computational fluid dynamics (CFD) modeling of mixing and heat transfer in the T-micro mixer was completed by ANSYS®. The effect of geometry and average input velocity of fluids on mixing process were observed. The result of this research included: (1) When the laminar flow is the dominant flow (Re is 25), the tracer mixing is not particularly seen. The tracer mixing is observed when the average velocity is increased (Re increases), (2) The heat flux to the wall (4.85x10-6 Watt/m2) occurred when T–micro mixer is no longer isothermal, (3) The scale–up to factor ten does not necessarily improve the mixing performance (Re is kept constant), and (4) When the shape of cross section is changed to circle (cross section area is kept constant), the mixing performance is not necessarily improved.ABSTRAKDifusi fluida dapat berjalan secara efektif jika memiliki gradien konsentrasi yang tinggi pada setiap bagian fluida. Hal ini dapat dicapai dengan memperkecil luas penampang pipa/unit proses menjadi ukuran mikro. Ukuran yang kecil pada mikro mixer menyebabkan difusi molekuler menjadi sangat efektif pada proses pencampuran. Pada penelitian ini, pemodelan untuk proses pencampuran dan perpindahan panas pada mikro mixer pasif dilakukan. Mikro mixer yang dipilih adalah jenis mixer berbentuk T (T –mikro mixer). Air digunakan sebagai medium dan tracer pasif kemudian dimasukkan untuk membedakan profil air yang berasal dari dua inlet yang berbeda. Profil pencampuran dan perpindahan panas dalam T–mikro mixer ini kemudian diamati. Pemodelan komputasi dinamika fluida pada T–mikro mixer dilakukan dengan menggunakan program ANSYS®. Efek geometri T – mikro mixer dan kecepatan fluida masuk diobservasi selama proses pencampuran. Hasil yang didapatkan dari penelitian ini adalah: (1) Pada saat kondisi aliran laminar dengan Re = 25, terlihat tidak ada proces pencampuran tracer (tracer mixing). Pencampuran tracer terlihat ketika laju alir dinaikkan (Re meningkat), (2) Flux perpindahan panas keluar sistem sebesar 4,85x10-6 Watt/m2ketika kondisi T – mikro mixer tidak lagi dijaga isotermal, (3) Peningkatan kinerja pencampuran juga tidak terlihat ketika T – mikro mixer dilakukan scale-up sepuluh kali lebih besar dari referensi (Re dijaga konstan), dan (4) Ketika bentuk penampang diganti dari segi empat menjadi lingkaran (luas penampang dijaga konstan), kinerja pencampuran tidak menjadi lebih baik.
oai:jurnal.ugm.ac.id:article/28245
2018-09-04T01:05:13Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/28245
2018-09-04T01:05:13Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 54-61
Pengaruh Penambahan Surfaktan Sodium Lignosulfonat (SLS) dalam Proses Pengendapan Nano Calcium Silicate (NCS) dari Geothermal Brine
Ulya, M Ridho; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Perdana, Indra; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Mulyono, Panut; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2018-01-23 07:33:33
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/28245
Geothermal brine; nano calcium silicate; precipitation; sodiumlignosulfonate
M. Ridho Ulya*, Indra Perdana, Panut Mulyono; Program Studi Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada
id
High concentration of dissolved silica in geothermal brine frequently causes operational problem in production of steam for electric generation. Mitigation of silica scaling is necessary to reduce the risk of steam production failure. In the present work, silicic acid in Dieng geothermal brine was reduced by introduction of calcium hydroxide that lead to formation of insoluble nano calcium silicates (NCS).The purpose of this work was to control size of the precipitated NCS by introducing surfactant sodium lignosulfonate (SLS) as surfactant in the Ca(OH)2 added geothermal brine. The effect of temperature (30, 50 and 70°C), pH (7, 8 and 9), and surfactant concentration (0.05, 0.15 and 0.30% (w/v)) on the particle size of the resulting NCS was studied to obtain the optimum operating condition. The precipitation-sedimentation behavior of the resulting particles was measured in a vertical tube. Having measured the solid density and solution density and viscosity, average diameter of the precipitated particles was determined using stoke’s principle. The calculated particle size was the compared with measurement result using particle size analyzer (PSA). The soluble silica concentration in the solution was measured using spectroscopy method while composition of the resulting solid particles was measured using EDX and FTIR. Experimental results showed that the dissolve silica in Dieng geothermal brine can be reduced and controlled with the addition of Ca(OH)2 and surfactant SLS. The greater the concentration of surfactant SLS, the smaller the resulting particle size. It was found that the formation of NCS particles was accompanied with precipitation of silica and salts. The optimum condition of NCS formation was at temperature 30°C and pH 9 while the concentration of surfactant SLS added to the brine was 0.3 % (w/v).ABSTRAKKonsentrasi yang tinggi dari kelarutan silika dalam larutan geothermal menyebabkan masalah dalam pengoperasian produksi uap di PLTP Dieng. Mitigasi silika scaling diperlukan untuk mengurangi resiko kegagalan produksi uap. Dalam penelitian ini, asam silika dalam larutan geothermal direaksikan dengan kalsium hidroksida (Ca(OH)2) membentuk n ano calcium silicate (NCS). Tujuan penelitian ini adalah membentuk endapan NCS dari surfaktan SLS dan Ca(OH)2 ke dalam larutan geothermal. Mempelajari perubahan suhu (30, 50 dan 70°C), pH (7, 8 dan 9), dan konsentrasi surfaktan (0,05, 0,15 and 0,30% (w/v) serta mengetahui kondisi optimum. Pengujian yang dilakukan yaitu pengendapan partikel yang dilakukan di gelas ukur vertical, densitas padatan, densitas larutan, viskositas, dan diameter rata-rata partikel yang mengendap ditentukan dari persamaan diameter stokes. Kemudian membandingkan hasil perhitungan dari diameter stokes dengan particle size analyzer (PSA). Konsentrasi silika yang terlarut dapat diukur dengan metode spectroscopy dan komposisi padatan di uji dengan instrumen EDX dan FTIR. Hasil penelitian menunjukkan bahwa silika terlarut dalam larutan geothermal berkurang dan dapat dikontrol dengan penambahan Ca(OH)2 dan penambahan surfaktan SLS. Semakin besar konsentrasi surfaktan maka ukuran partikel akan semakin kecil. Pembentukan NCS dapat dihasilkan dan disertai juga dengan partikel silika dan garam. Kondisi optimum pembentukan NCS terjadi pada suhu 30 oC pH 9 dan konsentrasi surfaktan SLS 0,30 %w/v.
oai:jurnal.ugm.ac.id:article/28890
2018-09-04T01:09:29Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/28890
2018-09-04T01:09:29Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 62-67
Evaluasi Nilai Difusivitas Ion Kalsium & Magnesium pada Proses "Low Salinity Waterflood" di Batuan Berea
Yusuf, Yusmardhany; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Purwono, Suryo; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Wirawan, Sang Kompiang; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2018-01-23 07:33:34
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/28890
Low salinity waterflood; diffusion; enhanced oil recovery; calcium diffusivity; magnesium diffusivity
id
In recent years Low Salinity Waterflood (LSW) had been supposed as trusty method to improve oil recovery and the most essential aspect is a alteration of divalent ion concentration in reservoir pore volume as a respon LSW. The objective of this paper are to find divalent diffusivity constant (Ca2+ and Mg2+) in berea sandstone by ionsmass conservation equation along with Atomic Absorption Spectroscopy (AAS) as validation. The study was conducted at 2 berea core having porosity : 0.235 and 0.230 and permeability : 661 mD and 550 mD, we use synthetic formation water accordance to "LN" field property. Experiment was treated by by diluting Ca2+ up to 79% from its original value and by diluting Mg2+ up to 95% from its original value while other ion were maintained fit to their original value. As a result we got difusion constant 0.0620 cm2.min-1 and 0.2667 cm2.min-1for Ca2+ and Mg2+, respectively.ABSTRAKPenelitian mengenai metode low salinity waterflood (LSW) dalam beberapa tahun terakhir mengalami perkembangan yang cukup pesat. Salah satu aspek esensial dalam metode tersebut adalah respon perubahan konsentrasi ion divalent dalam ruang pori reservoir. Penelitan ini bertujuan mencari konstanta difusivitas ion kalsium dan magnesium pada batuan Berea sandstone. Konstanta difusivitas dihitung menggunakan persamaan konservasi massa dan ditinjau secara difusi yang divalidasi oleh atomic absorption spectroscopy (AAS). Penelitian dilakukan pada 2 batuan Berea dengan porositas masing-masing: 661 mD dan 550 mD. Air formasi dibuat secara sintetik sesuai data lapangan "LN". Eksperimen difusivitas Ca2+ dilakukan dengan pengenceran hingga 79% dari konsentrasi awal. Sedangkan eksperimen Mg2+ dilakukan dengan pengenceran hingga 95% dari konsentrasi awal. Sementara itu ion lain diatur tetap sesuai konsentrasi awal. Dari hasil percobaan didapat konstanta difusivitas Ca2+ sebesar 0,0620 cm2/menitdan Mg2+ sebesar 0,2667 cm2/menit.
oai:jurnal.ugm.ac.id:article/30344
2018-09-04T01:14:22Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/30344
2018-09-04T01:14:22Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 68-77
Adsorpsi Air dari Campuran Uap Etanol-Air dengan Zeolit Sintetis 4A dalam Packed Bed dalam Rangka Produksi Fuel Grade Ethanol
Handrian, Handrian; Universitas Pembangunan Nasional "Veteran" Yogyakarta
Sediawan, Wahyudi Budi; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Mindaryani, Aswati; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2018-01-23 07:33:35
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/30344
Adsorption; molecular sieve; packed bed; zeolite 4A
id-ID
Ethanol can be used as fuel if it has a purity of 99.5%, while ethanol distillation will stop at its azeotrop point, ie at 95.6%. Adsorption of molecular sieve is one of the methods to obtain ethanol with level above the azeotropic point. Adsorbent that serves as molecular sieve is synthetic zeolite 4A. The adsorbent has a pore diameter of 3.9 Ǻ, then water and ethanol each has a molecular diameter of 2.75 Ǻ and 4.4 Ǻ. Hence the adsorbent is selective against the ethanol-water mixture. The purpose of this research is to obtain ethanol above its azeotropic point and to study the relationship between the influence of flow rate (Vz) and temperature (T) to changes in the number of mass transfer coefficient (kc), radial diffusivity (Der) and henry constants (H') which can be used as parameters in the design of adsorption tools on a commercial scale.This experiment was conducting by weighing zeolite 4A as much as 100 grams, then compiled and measured the height on packed bed column adsorbent. The heating regulator is switched on and set to a constant temperature of 80, 85, 90, 95 and 100 0C. Ethanol 95.61% with 250 ml volume is put into three-neck flask, then heat to evaporate. Turn on the cooling back and adjust the amount of formed vapor rate by adjusting the faucet opening and the degree of voltage in the heating mantle. The magnitude of the vapor flow rate is set at 2, 4 and 6 liters / minute. The products is accomodated and samples were taken every minute to analyze the ethanol content.This adsorption process gives the highest yield of ethanol with 99.40% content. The steam flow rate of 2 lpm and the temperature of 800C is the optimum combination in this research because much of the water vapor adsorbed on the 4A zeolite grain is 7.93 grams. The numerical calculation provides the result that the value of Der in this experiment is 1.59.10-3 cm2 / men, and the relation of kc are the function of reynolds and H' the function of temperature are as follows: kc = 7,95.10^-3.(Re)^0,1639 and H' = 4,47.10^-3.exp(2565,26/T) ABSTRAKEtanol dapat digunakan sebagai bahan bakar jika memiliki kemurnian 99,5%, sedangkan dislitasi etanol akan terhenti pada titik azeotropnya, yaitu pada 95,6%. Adsorpsi molecular sieve adalah salah satu metode untuk memperoleh etanol dengan kadar diatas titik azeotrop. Adsorbent yang berfungsi sebagai molecular sieve adalah zeolit sintetis 4A. Adsorbent ini memiliki diameter pori sebesar 3,9 Ǻ, lalu air dan etanol masing-masing memiliki diameter molekul 2,75 Ǻ dan 4,4 Ǻ. Maka dari itu adsorbent bersifat selektif terhadap campuran etanol-air. Penelitian ini bertujuan untuk memperoleh etanol diatas titik azeotropnya serta mempelajari hubungan pengaruh laju alir (vz) dan suhu (T) terhadap perubahan harga koefisien transfer massa (kc), difusivitas radial (Der) dan konstanta henry (H’) yang bisa digunakan sebagai parameter dalam perancangan alat adsorpsi pada skala komersial. Percobaan ini dilakukan dengan cara menimbang zeolit 4A sebanyak 100 gram, lalu disusun dan diukur tingginya pada packed bed columnadsorbent. Regulator pemanas dinyalakan dan diatur suhunya sampai konstan pada 80, 85, 90, 95 dan 1000C. Etanol 95,61% dengan volum 250 ml dimasukkan ke labu leher tiga, lalu dipanaskan sampai menguap. Pendingin balik dinyalakan dan diatur besarnya laju uap yang terbentuk dengan mengatur bukaan kran dan derajat voltase pada heating mantle. Besarnya laju aliran uap diatur pada 2, 4 dan 6 liter/menit. Produk ditampung dan diambil tiap menit sebagai sampel untuk dianalisis kadar etanolnya. Proses adsorpsi ini memberikan hasil tertinggi berupa etanol dengan kadar 99,40%. Laju alir uap 2 lpm dan suhu 800C adalah kombinasi yang optimal dalam penelitian ini karena banyak uap air yang teradsorpsi pada butir zeolit 4A yaitu 7,93 gram. Perhitungan secara numeris memberikan hasil bahwa nilai Der pada percobaan ini adalah 1,59.10-3 cm2/men, serta hubungan kc fungsi reynolds dan H’ fungsi suhu berturut-turut adalah sebagai berikut:kc=7,95.10-3..vz.D0,1639dan H'=4,47.10-3.e2565,26T
oai:jurnal.ugm.ac.id:article/31032
2018-02-21T09:14:00Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31032
2018-02-21T09:14:00Z
Jurnal Rekayasa Proses
Vol 9, No 2 (2015); 36-43
Modifikasi Sodium Lignosulfonat Melalui Epoksidasi Minyak Biji Kapuk dan Penambahan Kosurfaktan
Anam, Muhammad Khoirul
Purwono, Suryo
Supranto,
2015-11-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31032
The objective of this research is to reduce the interfacial tension of sodium lignosulfonate (SLS). SLS formulation (1%) showed the interfacial tension of 2.34 mN/m. This value is still relatively large when compared to interfacial tention of required surfactant for enhanced oil recovery (EOR). The terms of surfactants that can be used in EOR must have ≤10-3 mN/m interfacial tension. The performance of SLS was expected to be improved by adding the epoxide compound and co-surfactants (1-octanol). Epoxide compound was made by reacting kapok oil with acetic acid and hydrogen peroxide with in-situ method. Temperature of epoxidation reaction was varied i.e. 60°C, 70°C and 80°C, while the time of reaction was varied from 15 to 90 minutes. The evaluation showed that equation of the reaction rate coefficient (k) for the epoxide was 𝑘= 124,82 exp (−24,14/RT). The addition of the epoxide compound 0.5% w/w of the formulation SLS was able to reduce the interfacial tension value up to 9.95 x 10-2 mN/m. The addition of co-surfactant (1-oktanol) was varied between 0.1 and 0.4% of the total mass (SLS + epoxide + water formation). The lowest interfacial tension (2.43 x 10-3 mN/m) was obtained by co-surfactants addition of 0.2% w/w.
Keywords: Sodium lignosulfonat, epoxidation kapok oil, co-surfactant, interfacial tension, enhanced oil recovery
Penelitian ini bertujuan untuk menurunkan tegangan antarmuka dari sodium lignosulfonat (SLS). Pengukuran tegangan antarmuka yang telah dilakukaan pada formulasi sodium lignosulfonat atau SLS (1%) memiliki nilai tegangan antarmuka sebesar 2,34 mN/m. Nilai tegangan antarmuka dari SLS ini masih relatif besar jika dibandingkan dengan syarat surfaktan untuk perolehan kembali minyak bumi atau enhanced oil recovery (EOR). Syarat surfaktan sebagai agen EOR adalah memiliki nilai tegangan antarmuka sebesar ≤10-3 mN/m. Kekurangan dari SLS diharapkan dapat diperbaiki dengan penambahan senyawa epoksida dan kosurfaktan (1-oktanol). Senyawa epoksida dibuat dengan mereaksikan sabun minyak biji kapuk dengan asam asetat dan hidrogen peroksida secara insitu. Reaksi epoksidasi divariasikan pada suhu 60oC, 70oC, dan 80oC, sedangkan waktu reaksi divariasikan pada rentang 15 dan 90 menit. Persamaan konstanta laju reaksi untuk epoksidasi diperoleh sebesar 𝑘= 124,82 exp (−24,14/RT). Penambahan senyawa epoksida 0,5% w/w pada formulasi SLS mampu menurunkan nilai Tegangan antarmuka hingga 9,95x10-2 mN/m. Penambahan kosurfaktan 1-oktanol divariasikan antara 0,1–0,4% dari massa total formulasi utama (SLS+Epoksida+Air Formasi). Nilai tegangan antarmuka terkecil diperoleh pada penambahan kosurfaktan sebanyak 0,2% w/w, yaitu sebesar 2,43x10-3 mN/m.
Kata kunci: Sodium lignosulfonat, epoksidasi, minyak biji kapuk, kosurfaktan, tegangan antarmuka, enhanced oil recovery
oai:jurnal.ugm.ac.id:article/31033
2018-02-21T09:14:32Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31033
2018-02-21T09:14:32Z
Jurnal Rekayasa Proses
Vol 9, No 2 (2015); 44-50
Pemanfaatan Cangkang Biji Pala sebagai Briket dengan Proses Pirolisis
Rukmana,
Purwono, Suryo
Yuliansyah, Ahmad Tawfiequrrahman
2015-11-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31033
The abundance of nutmeg seed shells in Tidore is the reason to study the possibility to produce charcoal briquettes. The use of charcoal briquettes was expected to reduce waste of nutmeg seed shell and can be an alternative energy source with a high economic value. This study aims to investigate the effect of pyrolysis temperature and composition of tapioca adhesive to resulting quality of briquettes. The first step of the research was the preparation of nutmeg seed shells consisted of drying and size reduction into less than 20 mesh size. Afterward, the powder was put into furnace and heated to 350°C, 400°C, and 450°C for 90 minutes. During the process, volume of gas and liquids were measured every 15 minutes, while gas was sampled at 60-minute reaction. When pyrolysis was finished, about 20 g of charcoal was mixed with tapioca adhesive. The compositions of adhesive were 10%, 15%, 20%, 25%, and 30%. Finally, composite was formed in a cylindrical shape and compressed with hydraulic press at f 3 tons weight for a minute. The briquettes were then dried and analyzed with proximate analysis test. The results show that the highest calorific value was 6717.74 cal/g for material pyrolyzed at 450oC and 20% adhesive. The effect of adhesive on shatter index test showed that increasing composition of adhesive makes a better briquette quality as shown by a lower shatter index. In this study, the minimum weight loss was obtained by the addition of 30% adhesive.
Keywords: briquettes, nutmeg seed shells, pyrolysis
Ketersediaan cangkang biji pala yang melimpah di kota Tidore menjadi dasar dilakukannya penelitian mengenai pemanfaatan cangkang biji pala menjadi briket arang. Penggunaan briket arang diharapkan dapat mengurangi limbah cangkang biji pala dan sebagai sumber energi alternatif ramah lingkungan yang memiliki nilai ekonomi tinggi. Penelitian ini bertujuan untuk mempelajari pengaruh suhu pirolisis dan komposisi campuran perekat dengan arang cangkang biji pala terhadap kualitas briket. Tahap pertama dalam penelitian ini adalah penyiapan bahan baku berupa pengeringan dan penyesuaian ukuran cangkang biji pala sebesar 20 mesh. Tahap kedua yaitu proses pirolisis dengan cara memasukkan bubuk cangkang biji pala ke dalam tungku pirolisis (pirolisis selama 90 menit dengan variasi suhu 350oC, 400oC dan 450oC). Selama proses pirolisis berlangsung, volume gas dan cairan diukur setiap 15 menit, sedangkan pengambilan sampel gas dilakukan setelah pirolisis mencapai waktu 60 menit. Setelah dipirolisis, arang cangkang biji pala ditimbang seberat 20 gram kemudian bahan ini dicampurkan dengan perekat tapioka dengan variasi komposisi sebesar 10%, 15%, 20%, 25%, dan 30%. Setelah itu, arang cangkang biji pala dicetak dalam bentuk silinder dan dikempa dengan alat kempa hidrolik dengan berat 3 ton selama 1 menit. Briket kemudian dikeringkan dan dianalisis uji proksimat. Hasil uji proksimat menunjukkan bahwa nilai kalor yang tertinggi sebesar 6717,74 kal/g dimiliki oleh bahan hasil pirolisis suhu 450oC dengan campuran perekat 20%. Pengaruh perekat terhadap uji shatter index menunjukkan bahwa semakin tinggi kandungan perekat dalam briket maka semakin baik shatter index dari briket. Pada penelitian ini diketahui bahwa briket dengan penambahan perekat sebesar 30% mengalami kehilangan berat yang paling sedikit.
Kata kunci: briket, cangkang biji pala, pirolisis
oai:jurnal.ugm.ac.id:article/31034
2018-02-21T09:15:01Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31034
2018-02-21T09:15:01Z
Jurnal Rekayasa Proses
Vol 9, No 2 (2015); 51-57
Kinetika Reaksi Esterifikasi Gliserol Monoacetin dari Gliserol Hasil Samping Industri Biodiesel dan Asam Asetat dengan Katalisator Lewatit Monoplus s-100
Arsyad, Anita
Sulistyo, Hary
Sarto,
2015-11-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31034
Biodiesel is one of the potential candidates for alternative energy to replace fossil fuel. Glycerol is the side product in biodiesel production. To increase the economic value, glycerol can be processed through esterification to produce glycerol monoacetine. Monoacetine is very useful for non-food application such as printing ink, plasticizer, and intermediate material for biodegradable polyester. This research was conducted in batch reactor with variations of reaction temperatures (323 K-343 K), catalyst concentrations (3%, 5%, and 7% w/w of glycerol), and reactant ratios in terms of glycerol and acetate volume ratios (3:1, 5;1, and 7:1). Samples were withdrawn every 15 minutes up to 60 minutes of reaction time and the free fatty acid concentration was measured. Besides, the initial acid concentration and free glycerol in the raw material were also measured. The highest conversion was obtain as much as 63.86% at 343K, 7:1 reactant volume ratio (glycerol: acetic acid), and catalyst concentration of 3% of glycerol weight. The reaction kinetics of glycerol mono acetin production was modeled. Two kinetics models were used, which were pseudo-homogeneous catalytic model and heterogeneous catalytic model. Based on experimental data fitting on the models, it turned out that pseudo-homogeneous model was better representing the esterification of glycerol with Lewatit Monoplus s-100 catalyst.
Keywords: esterification, acetic acid, monoacetin glycerol, Lewatit Monoplus s-100
Biodiesel merupakan salah satu energi alternatif yang diharapkan dapat menggantikan bahan bakar diesel. Gliserol merupakan produk samping dari produksi biodiesel. Untuk meningkatkan nilai ekonominya, gliserol dapat diesterifikasi untuk membentuk gliserol monoacetin. Kegunaan monoacetin sangat banyak untuk keperluan non-makanan seperti pelarut dalam tinta cetak, plasticizer dan bahan baku poliester yang biodegradable. Penelitian ini dilakukan dalam sistem batch dengan variasi suhu reaksi 323 K–343 K, konsentrasi katalis 3%, 5% dan 7% dari massa gliserol, serta perbandingan volum pereaksi (gliserol:asam asetat) 3:1, 5:1 dan 7:1. Pengambilan sampel dilakukan setiap 15 menit sampai waktu 60 menit untuk dianalisis kadar asam bebasnya. Dalam penelitian ini kinetika reaksi gliserol monoacetin didekati dengan model matematis yang disusun dari persamaan neraca massa. Hasil percobaan menunjukkan konversi tertinggi diperoleh sebesar 63,86% pada suhu 343 K, perbandingan volum gliserol: asam asetat sebesar 7:1 dan konsentrasi katalis 3% dari massa gliserol yang digunakan. Pada penelitian ini, diuji 2 model kinetika reaksi yaitu model katalitik pseudo-homogen dan model `katalitik heterogen. Berdasarkan kesesuaian dengan data eksperimen, model pseudo-homogen lebih sesuai untuk esterifikasi gliserol dengan katalisator Lewatit Monoplus s-100.
Kata kunci: esterifikasi, asam asetat, gliserol monoacetin, Lewatit monoplus s-100
oai:jurnal.ugm.ac.id:article/31035
2018-02-21T09:15:15Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31035
2018-02-21T09:15:15Z
Jurnal Rekayasa Proses
Vol 9, No 2 (2015); 58-64
Penguraian Limbah Organik secara Aerobik dengan Aerasi Menggunakan Microbubble Generator dalam Kolam dengan Imobilisasi Bakteri
Shalindry, Riysan Octy
Rochmadi,
Budhijanto, Wiratni
2015-11-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31035
The abundance utilization of the water in life can lead to decrease water quality in the earth. To resolve these problems an efficient alternative waste treatment is needed. This research studied the aerobic wastewater treatment using the microbubble generator (MBG) type of porous pipe and orifice as an oxygen supply (aerator) to treat artificial waste in pond of 3m x 3m x 1m dimension. Attached culture growth using pumice as biofilm media was applied. The main focus of this research was the influence of the aeration intensity variation of MBG as the result of liquid flow rate (QL) and air flow rate (QG) combination upon the decrease of organic content measured as sCOD (soluble Chemical Oxygen Demand). The value of QG was varied at 0.0150; 0.0300; and 0.0450 m3/h while QL value was varied at 12, 14, and 16 m3/h. The data obtained were evaluated based on oxygen mass transfer performance represented by the value of kL. The value of kL was used as a reference in determining the best combination of QG and QL for reducing sCOD in aerobic wastewater treatment. From the results of the research, the best combination of QG and QL for aerobic waste treatment was at QG 0.0300 m3/h and QL 14 m3/h (at 0.0450 QG m3/h). Although the research was still exploratory, the obtained trends and numbers were very useful for optimizing the MBG performance.
Keywords: aerobic waste treatment, microbubble, microbubble aeration, microbubble generator, biofilm, attached growth
Penelitian ini mempelajari pengolahan air limbah secara aerobik menggunakan Microbubble Generator (MBG) tipe porous pipe dan orifice sebagai alat suplai oksigen (aerator) untuk mengolah limbah artifisial pada kolam berukuran 3m x 3m x 1m. Aerasi diuji coba dengan bakteri pengurai berupa biakan melekat (attached culture) pada batu apung berukuran diameter 2-4 cm. Fokus utama dari penelitian ini adalah pengaruh variasi kombinasi kecepatan aliran cairan (QL) dan kecepatan aliran udara (QG) pada MBG terhadap penurunan kadar bahan organik yang dinyatakan sebagai nilai sCOD (soluble Chemical Oxygen Demand). Nilai QG divariasikan pada 0,0150; 0,0300 dan 0,0450 m3/jam sedangkan untuk nilai QL pada 12, 14 dan 16 m3/jam. Data yang diperoleh pada penelitian dievaluasi menggunakan konstanta transfer massa (kL). Nilai kL digunakan sebagai acuan dalam menentukan kombinasi QG dan QL terbaik dalam penurunan konsentrasi sCOD pada limbah aerobik. Dari hasil penelitian ini nilai kL yang relatif baik dan stabil diperoleh pada kombinasi QG 0,030 m3/jam (untuk QL 16 m3/jam) dan QL 16 (pada QG 0,045 m3/jam). Walaupun penelitian ini masih bersifat eksploratif, trend dan konstanta yang diperoleh sangat berharga untuk mengoptimasi kinerja MBG.
Kata kunci: Pengolahan limbah aerobik, microbubble, aerasi microbubble, microbubble generator (MBG), biofilm, pertumbuhan melekat
oai:jurnal.ugm.ac.id:article/31036
2018-02-21T09:15:39Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31036
2018-02-21T09:15:39Z
Jurnal Rekayasa Proses
Vol 9, No 2 (2015); 65-70
Evaluasi Efek Pre-treatment Ultrasonik pada Proses Hidrolisis Enzimatis Ampas Tahu
Hapsari, Farlina
Prasetyo,, Imam
Budhijanto, Wiratni
2015-11-01 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31036
Utilization of biomass as alternative energy source is one of the attempts to reduce the dependence on petroleum based energy which is currently still used as the primary energy source. Tofu solid waste is one of the potential biomass sources that have not been fully utilized. Tofu solid waste was mostly comprised of complex molecular structures composed of cellulose, hemicellulose and lignin. Various techniques of pretreatments have been studied to change the physical structure and chemical properties of the biomass to improve its digestibility in enzymatic hydrolysis process. This research studied the effect of ultrasonic pretreatment on tofu solid waste prior to the enzymatic hydrolysis to maximize the conversion of the cellulose into glucose. Ultrasonic pretreatment was conducted by using a water bath equipped with ultrasonic equipment (sonicator) run at the wave frequency of 20 kHz and power of 5 kW. Ultrasonic pretreatment with variations of time (10, 20 and 30 minutes) and temperatures (60 °C, 80 °C, 100 °C) were carried out. Following the pretreatment, hydrolysis tests were conducted on pretreated samples using cellulase enzymes in 100 ml batch reactor at 45 oC and pH 5. Samples were taken every 1 hour for 6 hours of the reaction and glucose concentration in every sample was measured. The highest cellulosic conversion in enzymatic hydrolysis was obtained on the biomass which was pretreated with ultrasonic for 20 minutes.
Keywords: tofu solid waste, enzymatic hydrolysis, pretreatment, ultrasonic
Pemanfaatan biomassa sebagai sumber energi alternatif merupakan salah satu usaha untuk mengurangi ketergantungan terhadap penggunaan energi minyak bumi yang saat ini masih dipandang sebagai sumber energi utama. Ampas tahu adalah salah satu biomassa yang belum termanfaatkan secara maksimal. Ampas tahu merupakan salah satu biomassa yang memiliki struktur molekul yang kompleks, yang terdiri atas selulosa, hemiselulosa dan lignin. Telah banyak publikasi tentang berbagai teknik pretreatment untuk mengubah struktur fisik dan kimia dari biomassa untuk meningkatkan konversi selulosa pada proses hidrolisis enzimatis. Penelitian ini mempelajari pengaruh pretreatment ultrasonik pada ampas tahu sebelum hidrolisis enzimatis. Penelitian ini dilakukan dengan menggunakan waterbath yang dilengkapi alat ultrasonik (sonikator) dengan frekuensi 20 kHz dan power 5 kW. Dalam penelitian ini dipelajari pretreatment ultrasonik dengan variasi waktu (10, 20 dan 30 menit) dan suhu (60°C, 80°C, 100°C). Ampas tahu yang sudah mengalami pretreatment ultrasonik, selanjutnya dihidrolisis dengan menggunakan enzim selulase dalam reaktor batch dengan volume 100 ml pada suhu 45oC dan pH 5. Pengambilan sampel dilakukan setiap 1 jam selama 6 jam reaksi untuk dianalisis kadar glukosa. Konversi tertinggi pada hidrolisis enzimatis diperoleh pada bahan biomassa dengan pretreatment ultrasonik selama 20 menit.
Kata kunci: ampas tahu, hidrolisis enzimatis, pretreatment, ultrasonik
oai:jurnal.ugm.ac.id:article/31136
2018-09-04T01:20:55Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31136
2018-09-04T01:20:55Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 86-93
Pengaruh Penambahan Limestone terhadap Kuat Tekan Semen Portland Komposit
Purnawan, Irfan; Program Studi Teknik Kimia, Fakultas Teknik, Universitas Muhammadiyah Jakarta
Prabowo, Andi; Program Studi Teknik Kimia, Fakultas Teknik, Universitas Muhammadiyah Jakarta
2018-01-23 07:33:36
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31136
Cement; portland composite cement; limestone; compressive strength; additives; clinker
id-ID
Cement is the main component of construction that makes it a significant commodity. Portland Composite Cement (PCC) is one of new cement variants that has similar characteristic to Portland Cement, but with better quality, more environmentally friendly and cheaper in price. The objective of this research is to understand the influence of limestone to the compressive strength of the cement and to determine the percentage of added limestone that gives maximum compressive strength to PPC. The limestone varies added to the cement are 0, 5, 10, 15, 20 and 25%. The impact of added limestone can be studied from several tests such as fineness test, residue test, chemical composition test and cement compressive strength. The result shows that the higher percentage of limestone added to the cement, the higher the result for residue test and fineness test, but lower result for compressive strength. The highest compressive strength obtained is at 2 days age while the best composition of the blended cement is 77% clinker, 15% limestone, 3% gypsum and 5% blast furnace slag. ABSTRAKSemen merupakan bahan dasar utama konstruksi bangunan. Hal ini menjadikan semen merupakan komoditi yang strategis. Portland Composite Cement (PCC) merupakan jenis semen varian baru yang mempunyai sifat dan karakteristik hampir sama dengan semen Portland. Namun semen jenis PCC ini mempunyai kualitas yang lebih baik, ramah lingkungan dan harga yang lebih ekonomis. Tujuan penelitian ini adalah mengetahui pengaruh penambahan limestone dengan berbagai variasi terhadap kuat tekan dan menentukan massa limestone yang dapat memberikan kuat tekan maksimum pada semen Portland komposit. Pembuatan semen Portland komposit dilakukan dengan penambahan limestone sebagai aditif. Variasi limestone yang ditambakan adalah 0, 5, 10, 15, 20 dan 25%. Pengaruh penambahan limestone dapat diketahui dari hasil uji kehalusan, uji residu, uji komposisi kimia semen dan uji kuat tekan semen. Hasil penelitian menunjukan bahwa semakin besar persentase pemakaian limestone di dalam blended cement maka nilai residu dan nilai kehalusan akan semakin besar namun nilai kuat tekan akan semakin rendah. Kuat tekan semen yang tertinggi yaitu nilai kuat tekan pada umur 2 hari. Komposisi terbaik aditif limestone di dalam blended cement adalah 77% clinker, 15% limestone, 3% gypsum dan 5% blast furnace slag.
oai:jurnal.ugm.ac.id:article/31147
2018-09-03T16:48:19Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31147
2018-09-03T16:48:19Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 94-100
Analisis Pengaruh Bahan Dasar terhadap Indeks Viskositas Pelumas Berbagai Kekentalan
Siskayanti, Rini; Program Studi Teknik Kimia, Fakultas Teknik, Universitas Muhammadyah Jakarta
Kosim, Muhammad Engkos; Program Studi Teknik Kimia, Fakultas Teknik, Universitas Muhammadyah Jakarta
2018-01-23 07:33:37
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31147
Mineral lubricant; synthetic lubricant; viscosity index
id-ID
Lubricants are chemicals, which are generally liquid, provided between two moving objects to reduce frictional forces. The lubricant is made from a 70-90% base oil mixture and added with an additive to enhance its properties. Basic lubricants can be grouped into 3 ie mineral lubricants, vegetable lubricants and synthetic lubricants. One of the functions of lubricants is as an engine coolant from heat arising from friction and sealing. Lubricant resistance to temperature changes is strongly influenced by the type of lubricant base material. The purpose of this research is to know the influence of basic material of lubricant to temperature change as measured by Viscosity Index value. Research done by making machine lubricant with various viscosity with addition of same additives, only kind of lubricant that used different but still refers to standard lubricant characteristic tested. Of 5 samples tested were DEO API CI-4 SAE 15W-40, API PCMO SN SAE 10W-40, API MCO SL SAE 10W-30, HO ISO VG 32, TO API TO-4 SAE 10W showed that lubricant using materials Synthetic foundations have higher viscosity index values than minerals (13-30% higher). This indicates that the quality of lubricants is also getting better. ABSTRAKPelumas adalah zat kimia umumnya berupa cairan, yang diberikan di antara dua benda yang bergerak dengan tujuan untuk mengurangi gaya gesek. Pelumas dibuat dari 70-90% campuran minyak pelumas dasar dan ditambah dengan bahan aditif untuk meningkatkan sifat-sifatnya. Minyak pelumas dasar dapat dikelompokkan menjadi 3 yaitu minyak pelumas mineral, minyak pelumas sintetis dan minyak pelumas nabati. Pelumas mineral adalah pelumas yang dibuat dengan bahan baku minyak pelumas dasar mineral (golongan I dan II) dan pelumas sintetis adalah pelumas yang dibuat dari minyak pelumas dasar sintetis (golongan III, IV, V). Semakin tinggi golongan bahan dasar pelumas maka kualitas pelumas akan semakin baik. Ketahanan pelumas terhadap perubahan temperatur sangat dipegaruhi oleh jenis bahan dasar pelumas. Tujuan penelitian ini untuk mengetahui pengaruh bahan dasar pelumas terhadap perubahan temperatur yang diukur dengan nilai indeks viskositas. Penelitian dilakukan dengan cara membuat pelumas mesin pada berbagai kekentalan dan penambahan aditif yang sama. Namun jenis minyak pelumas dasar yang digunakan berbeda tetapi tetap mengacu pada standar karakteristik pelumas yang diuji. Dari 5 sampel yang diuji yaitu DEO API CI-4 SAE 15W-40, PCMO API SN SAE 10W-40, MCO API SL SAE 10W-30, HO ISO VG 32, TO API TO-4 SAE 10W menunjukkan bahwa pelumas dengan menggunakan bahan dasar sintetis mempunyai nilai indeks viskositas yang lebih tinggi jika dibandingkan yang mineral (13-30% lebih tinggi). Hal ini menunjukkan bahwa kualitas pelumas juga semakin baik.
oai:jurnal.ugm.ac.id:article/31163
2019-02-22T15:50:50Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/31163
2019-02-22T15:50:50Z
Jurnal Rekayasa Proses
Vol 12, No 1 (2018); 1-8
Pengaruh Steam Pretreatment terhadap Degradasi Selulosa dan Limonen pada Limbah Jeruk dalam Produksi Biohidrogen
Khaerunnisa, Gita; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada, Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Sarto, Sarto; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada, Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Sutijan, Sutijan; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada, Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Syamsiah, Siti; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada, Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2018-07-17 08:59:29
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/31163
Orange waste; hydrogen; limonene; cellulose; steam pretreatment
Bakrie Graduate Fellowship
id
This research presents the influence of steam pretreatment to orange waste and its effect on the production of biohydrogen. The steam pretreatments with various times of 2, 4, and 6 hours were applied to the samples. After the pretreatment, the samples were fermented for seven days, and the contents of cellulose, limonene, volatile fatty acid (VFA), and hydrogen were assessed on the days of 1, 2, 3, 5 and 7. Kinetic parameters of hydrogen production were evaluated using the modified Gompertz`s equation. The result of this research showed that the steam pretreatment significantly reduced the cellulose and limonene compounds. The content of cellulose in the substrate after 2, 4 and 6 hours pretreatment were 37.08%; 36.63%; and 15.95%, respectively. Moreover, the content of limonene after pretreatment of 2, 4, and 6 hours were 57.44 ppm; 38.80 ppm; and 36.11 ppm, respectively. Analysis of kinetic parameters of production of hydrogen showed that the maximum productions of hydrogen (Hmax) in the samples after pretreatment of 2, 4, and 6 hours were 11.492 mL; 52.612 mL; 22.345 mL, respectively. The maximum production rates (Rm) at specified pretreatment time (2, 4, and 6 hours) were 9.888 mL H2/hour; 10.008 mL H2/hour; 12.982 mL H2/hour and the lag phases were 49.689 hours; 24.742 hours; and 24.885 hours. The study elucidated that applying pretreatment for 4 hours gives the optimum condition for hydrogen production. A B S T R A KPenelitian ini mempelajari pengaruh steam pretreatment terhadap limonen dan selulosa yang terkandung pada limbah jeruk, dengan mengevaluasi dampaknya terhadap produksi biohidrogen. Steam pretreatment dilakukan dalam 3 variasi waktu, yaitu 2, 4 dan 6 jam. Kemudian proses fermentasi dijalankan selama 7 hari dengan pengambilan sampel dilakukan pada hari ke 1, 2, 3, 5 dan 7. Hasil dari penelitian ini menunjukkan bahwa steam distillation yang dilakukan untuk pretreatment pada substrat jeruk berpengaruh terhadap kondisi substrat, yaitu mengurangi kadar selulosa dan limonen. Kadar selulosa pada substrat setelah pretreatment 2 jam adalah 37,08%; 4 jam 36,63%; dan 6 jam 15,95%. Sementara kadar limonen setelah pretreatment 2, 4 dan 6 jam berturut-turut 57,44 ppm; 38,80 ppm; dan 36,11 ppm. Konstanta kinetika produksi hidrogen pada sampel dengan pretreatment 2, 4 dan 6 jam yang diperoleh dengan persamaan Gompertz termodifikasi adalah potensi produksi hidrogen (Hmaks) 11,492 mL; 52,612 mL; 22,345 mL, laju produksi maksimum (Rm) 9,888 mL H2/jam; 10,008 mL H2/jam; 12,982 mL H2/jam serta waktu adaptasi 49,689; 24,742; dan 24,885 jam. Perlakuan pretreatment pada sampel selama 4 jam menghasilkan produk paling optimal.
oai:jurnal.ugm.ac.id:article/33194
2018-09-04T01:24:15Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/33194
2018-09-04T01:24:15Z
Jurnal Rekayasa Proses
Vol 11, No 2 (2017); 101-104
Seleksi Isolat Bakteri Amilolitik dari Rhizosfer Canna edulis, Kerr. untuk Produksi Poli Hidroksi Alkanoat dari Limbah Cair Tapioka
Nurhayati, Nurhayati; Departemen Biologi Fakultas Sains dan Matematika Universitas Diponegoro
Radjasa, Ocky Karna; Departemen Perikanan dan Kelautan Universitas Diponegoro
Prijambada, Irfan Dwidya; Lab. Mikrobiologi Tanah dan Lingkungan Fakultas Pertanian Universitas Gadjah Mada
2018-03-07 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/33194
Canna edulis; Kerr. rhizosphere; wastewater; assava industry flour; PHA; bakteri
id-ID
Petrochemical-based plastic waste accumulated in landfills have been posing serious threat to the environment as this kind of plastics are non-biodegradable. Replacing petrochemical-based plastics with biodegradable plastics constitutes a challenging solution both in terms of mechanical design of the process and most importantly the availability of powerful local microorganism for the process. Therefore, the current study was searching for appropriate local microorganisms for poly hydroxyl alkanoate (PHA) production from starch waste, which was considered as one of cheap carbon sources. Waste water of cassava industry is a good resource of such starch waste water. The microbes were isolated from Canna edulis, Kerr. rhizosphere from Cangkringan. The expected isolates were the bacteria enable the coupling of carbon catabolic pathways with PHA anabolic pathways. It was found that ten isolates were able to use waste water of cassava flour industry as carbon source. The PHA quantitative analysis by spectrophotometer showed that the isolate of Bacillus sp. C8 produced the highest PHA of 2,095 g/L. Further FTIR analysis showed specific bands near 1363,67 cm-1, 1641,42 cm-1, 2929,87 cm-1, 3408,22 cm-1 wavelengths which revealed the presence of CH3, ester carbonyl group (C=O), C-H and terminal OH group of PHA. ABSTRAKAkumulasi sampah plastik berbasis petrokimia di tempat pembuangan sampah mengganggu lingkungan karena plastik sifatnya tidak mudah didegradasi secara biologi dan sangat tahan di lingkungan. Penggantian plastik yang berasal dari bahan petrokimia dengan bahan plastik yang mudah terdegradasi secara biologi merupakan tantangan tersendiri, baik dari sisi perancangan proses maupun ketersediaan mikrobia lokal yang sesuai untuk proses tersebut. Oleh karena itu, penelitian ini dilakukan sebagai upaya untuk mendapatkan bakteri lokal penghasil PHA yang mampu mengkonsumsi substrat berupa pati. Substrat pati dipilih karena ketersediaan limbat industri tapioka sebagai bahan baku potensial dan murah untuk produksi PHA. Bakteri amilolitik untuk produksi PHA telah berhasil diisolasi dari rhizosfer Canna edulis, Kerr. di Cangkringan, Sleman, Yogyakarta, Indonesia. Bakteri yang diisolasi merupakan bakteri dengan kemampuan memproduksi PHA dan memiliki kemampuan melakukan rangkaian reaksi pada limbah cair industri tapioka dan rangkaian reaksi pembentukan PHA. Telah berhasil didapatkan 10 bakteri yang memiliki aktivitas amilolitik dan dapat menghasilkan PHA menggunakan limbah cair industri tapioka. Analisis kuantitatif PHA menggunakan spektrofotometer menunjukkan bahwa isolat Bacillus sp. C8 menghasilkan PHA paling tinggi sebesar 2,095 mg/mL. Analisis hasil metabolism isolat C8 menggunakan FTIR memperlihatkan puncak spesifik 1363,67 cm-1, 1641,42 cm-1, 2929,87 cm-1, 3408,22 cm-1 adalah verifikasi adanya CH3, C=O, C-H dan OH dari PHA.
oai:jurnal.ugm.ac.id:article/33335
2018-05-10T01:29:16Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/33335
2018-05-10T01:29:16Z
Jurnal Rekayasa Proses
Vol 10, No 2 (2016); 36-42
Kinetika Adsorpsi Nikel (II) dalam Larutan Aqueous dengan Karbon Aktif Arang Tempurung Kelapa
Adiningtyas, Ardelita; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Mulyono, Panut; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2016-11-20 00:00:00
Articles published in J. Rek. Pros. are licensed under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license, which permits anyone to copy, transform, or redistribute articles for any lawful purpose in any medium, provided appropriate credit is given to the original author(s) and J. Rek. Pros. is recognized as its original publisher. A link to this license should also be provided. Any derivative work of an article published in J. Rek. Pros. must also be shared under the same (or compatible) license.Both copyright and publishing rights on articles are retained by the respective author(s), without restrictions. Only a non-exclusive license is granted to J. Rek. Pros. to publish the article and identify itself as its original publisher.Any submission to J. Rek. Pros. will be taken to mean all authors associated with the manuscript agree to these conditions.
url:https://journal.ugm.ac.id/jrekpros/article/view/33335
Adsorption kinetic; nickel (II); activated carbon; coconut shell
id-ID
The adsorption kinetics of nickel (II) in aqueous solution with activated carbon from coconut shell was studied by measuring the nickel concentration in the solution (C) as a function of time (t). The parameters studied in this study were adsorption temperature (T), particle diameter of activated carbon (d), and mass ratio of activated carbon to aqueous solution (r). It was found that the adsorption rate increased with the increase of the adsorption temperature and the mass ratio of activated carbon to aqueous solution. On the contrary, it was found that the rate of adsorption decreased with increasing the particle diameter of the activated carbon. ABSTRAKKinetika adsorpsi larutan nikel (II) dalam air dengan karbon aktif tempurung kelapa dianalisis dengan mengukur konsentrasi nikel pada larutan sebagai fungsi waktu. Parameter yang digunakan pada penelitian ini adalah suhu adsorpsi (T), diameter partikel karbon aktif tempurung kelapa (d), dan rasio massa karbon aktif tempurung kelapa dengan larutan nikel (II) dalam air (r). Hasil penelitian menunjukkan bahwa laju adsorpsi meningkat dengan bertambahnya suhu adsorpsi dan rasio massa karbon aktif tempurung kelapa dengan larutan. Sedangkan, laju adsorpsi menurun dengan bertambahnya ukuran diameter partikel karbon aktif tempurung kelapa.
oai:jurnal.ugm.ac.id:article/33336
2018-05-10T01:29:16Z
jrekpros:ART
v2
https://journal.ugm.ac.id/jrekpros/article/view/33336
2018-05-10T01:29:16Z
Jurnal Rekayasa Proses
Vol 10, No 2 (2016); 43-47
Pengaruh Variasi Organic Loading Rate Sampah Buah Jeruk terhadap Produksi Biohidrogen pada Reaktor Kontinu
Bonanza, Baruna Sakti Wicaksono; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
Sarto, Sarto; Departemen Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika No.2 Kampus UGM, Yogyakarta, 55281
2016-11-20 00:00:00
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url:https://journal.ugm.ac.id/jrekpros/article/view/33336
Biohydrogen; dark fermentation; orange waste; organic loading rate
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Biohydrogen is a potential alternative energy generated through the process of dark fermentation of organic waste. This research aims to determine the effect of organic loading rate (OLR) variations of orange waste on biohydrogen production. This research dealt with the production of biohydrogen in the continuous system. The reactor was equipped with circulation and operated anaerobically. The inoculum was taken from the sludge of the biogas installation in Gemah Ripah Fruit Market. Orange waste was used in three variations of organic loading rate (OLR) at 2.2, 2.5, and 3.1 L/day. The results revealed that the daily productions of gas for those OLR are about 15, 35, and 26 L/day respectively. Futhermore, for OLR of 2.5 L/day the total solid decreased from about 8 to 5%. ABSTRAKBiohidrogen merupakan salah satu jenis energi alternatif yang dapat dihasilkan dari proses fermentasi gelap (dark fermentation) sampah organik. Penelitian ini bertujuan untuk mengetahui pengaruh variasi organic loading rate (OLR) sampah buah jeruk terhadap produksi biohidrogen. Pada penelitian ini produksi biohidrogen dilakukan menggunakan sistem kontinu. Reaktor yang digunakan dilengkapi dengan sirkulasi dan dijaga pada kondisi anaerob. Inokulum berasal dari sludge dari instalasi biogas Pasar Buah Gemah Ripah. Substrat yang digunakan adalah buah jeruk, sedangkan variabel yang dipelajari adalah OLR yang divariasikan sebesar 2,2; 2,5; dan 3,1 L/hari. Hasil penelitian menunjukkan bahwa produksi gas untuk OLR tersebut berturut-turut sekitar 15, 35, dan 26 L/hari. Pada OLR 2,5 L/hari, terjadi penurunan total solid dari sekitar 8% menjadi sekitar 5%.
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