| dc.description.abstract | Adsorption is the most efficient method for removing colourants, but adsorbent modification with surfactant is still rarely performed, surfactant can change the selectivity of adsorbent by modifing its surface charge. Natrium dodecyl sulphate (NDS) and hexadecyltrimethylammonium bromide (HDTMABr) are anionic and cationic surfactant used in this study. Adsorbent (mixture of kaolin-tapioca solid waste) (75:25) were soaked with surfactant (NDS and HDTMA-Br) at concentration 0, 50, 100, 300, and 600% CMC (critical micelle concentration). The result showed that the control adsorbent (0% CMC surfactant) had adsorptivity of 7.50 mg/g. NDS solution could increase the adsorptivity of adsorbent, while the adsorbent immersed in HDTMA-Br decreased the adsorptivity as compared with the control treatment. Isotherm adsorption for methylene blue using the best adsorbent (adsorbent with soaking 600% CMC NDS), followed Freundlich isotherm. | en |
