The Effect of Coal Fly Ash Crystallinity toward Methyl Violet Adsorption Capacity

https://doi.org/10.22146/ajche.50090

Widi Astuti(1*), I Made Bendiyasa(2), Endang Tri Wahyuni(3), Agus Prasetya(4)

(1) Chemical Engineering Department, Semarang State University, Semarang, Indonesia
(2) Chemical Engineering Department, Gadjah Mada University, Yogyakarta, Indonesia
(3) Chemistry Department, Gadjah Mada University, Sekip Utara Yogyakarta, Indonesia
(4) Chemical Engineering Department, Gadjah Mada University, Yogyakarta, Indonesia
(*) Corresponding Author

Abstract


Coal fly ash (CFA) generated by coal-based thermal power plants is mainly composed of some oxides having high crystallinity, like quartz and mullite. In this study, the effect of CFA crystallinity toward methyl violet (MV) adsorption capacity was investigated. To decrease crystallinity of CFA, the solution of sodium hydroxide (NaOH) of 1-7 M was used to treat CFA at various temperatures and reflux time. Then, to evaluate the effect of NaOH-treated CFA with respect to adsorption capacity, the original and NaOH-treated CFA were tested its MV adsorption capacity in batch experiments. Original or NaOH-treated CFA was contacted with 50 mL of MV solution at temperature of 26oC. The effects of contact time, pH of solution, adsorbent dose and initial concentration of dye on the adsorption of MV were investigated. The results show that CFA treated with low NaOH concentration (1-3 M), temperature of 60oC and 2 hours reflux time, the crystallinity of quartz and mullite decreases, but its capacity on MV adsorption increases from 34% to 97%. At higher NaOH concentration (>3M), in the range of studied reflux temperature and time, it is found that decreasing quartz and mullite crytallinity are followed by a hydroxysodalite formation which causes the decreasing of MV adsorption from 97% to 83%. The highest adsorption capacity of NaOH-treated CFA was found 1.24 x 10-5 mol g-1. Adsorption kinetics of MV onto NaOH-treated CFA could be approximated with a pseudo second order kinetic model with the rate constant was 3.2 x 103 g mol-1 min-1.

Keywords


coal fly ash, crystallinity, quartz, mullite, methyl violet, adsorption

Full Text:

PDF


References

  1. Al-Degs, Y.A., El-Barghouthi, M.I., El-Sheikh, A.H., Walker, G.M. (2008). Effect of solution pH, ionic strength, and temperature on adsorption behavior of reactive dyes on activated carbon. Dyes and Pigments.77:16- 23
  2. Dogan, M., Ozdemir, Y., Alkan, M. (2006). Adsorption kinetics and mechanism of cationic methyl violet and methylene blue dyes onto sepiolite. Dyes and Pigments. 75:701-713.
  3. Eren, Z. and Acar, F.N. 2006. Adsorption of Reactive Black 5 From An Aqueous Solution :Equilibrium and Kinetic Studies. Desalination 194 (2006) 1-10.
  4. Hefne, J.A., Mekhemer, W.K.,Alandis, N.M., Aldayel, O.A., Alajyan, T. (2008). Kinetic and thermodynamic study of the adsorption of Pb(II) from aqueous solution to the natural and treated bentonite. International Journal of Physical Sciences, 3, 281-288.
  5. Mall, I.D., Srivastava, V.C., Agarwal, N.K. (2005). Removal of orange-G and methyl violet dyes by adsorption onto bagase fly ash- kinetic study and equilibrium isotherm analyses. Dyes and Pigments. 69:210-223.
  6. Ofomaja,A.E., Ho,Y.S. (2008). Effect of temperatures and pH on methyl violet biosorption by mansonia wood sawdust. Bioresource Technology : 99:5411-5417.
  7. Wen, D., Ho, Y.S., Tang, X. (2006). Comparative sorption kinetics studies of ammonium onto zeolite. J.Hazard.Mater. B 133, 252-256
  8. Woolard, C.D., Petrus, K., Horst, M.V.D. (2000). The use of a modified fly ash as an adsorbent for lead. Water SA vol 26 No. 4. p.531 – 536.
  9. Yamada, K., Haraguchi, K., Gacho, C.C., Wongsiri, B.P., Pena, M.L. 2003. Removal of Dyes from Aqueous Solution by Sorption with Coal Fly Ash. International Ash Utilization Symposium, University of Kentucky, paper 116.



DOI: https://doi.org/10.22146/ajche.50090

Article Metrics

Abstract views : 1111 | views : 918

Refbacks

  • There are currently no refbacks.


ASEAN Journal of Chemical Engineering  (print ISSN 1655-4418; online ISSN 2655-5409) is published by Chemical Engineering Department, Faculty of Engineering, Universitas Gadjah Mada.