Qadariyah, L., Aurelitha, K. S., Nafiah, R. A., & Aswie, V. (2026). Production of Sodium Lignosulfonate Surfactant from Oil Palm Empty Fruit Bunches Lignin using Ultrasound-assisted Method. ASEAN Journal of Chemical Engineering, 26(2), 355–374. https://doi.org/10.22146/ajche.27301