Novia Nadzifah et al. 2026. Adsorption of Sulfate Ions (SO42-) from Distillery Spent Wash Using Biochar Derived from Digestate Biogas. AJARCDE (Asian Journal of Applied Research for Community Development and Empowerment). 10, 3 (Jul. 2026), 22–33. DOI:https://doi.org/10.29165/ajarcde.v10i3.1032.