A study of the performance of modified Zeolite in removing Humic Acid from aqueous solutions

Existence of acid humic in water resources is undesirable and causes carcinogenic component in disinfection process due to reaction with chlorine. Due to their cost-effectiveness and higher physical resistance than activated carbon, natural zeloites are used for removing various pollutants. . In the present study, Iranian natural zeolite modified with cetylpyridinium bromide (CPB) was investigated for removing humic acid (HA) in an aqueous solution. In addition, common isotherms and kinetics in water and wastewater are studied. The effects of parameters such as initial humic acid viscosity, adsorbed dose. pH, and contact time with modified zeolite on humic acid adsorption were investigated. Findings indicated that increased contact time and adosorbed dose increases the efficiency of humic acid removal and increased pH decreases the removal efficiency of modified zeolite. The initial pH of the HA solution strongly affected the efficiency of SMZ for HA removal in an aqueous solution. The optimum initial pH values were in acidic levels for adsorption of the HA on SMZ. Furthermore, Langmuir isotherm and second-order kinetics were found to be the best models for explaining humic acid adsorption reactions on modified zeolite adsorbent.. This study showed that Iranian natural zeolite modified with cetylpyridinium bromide (CPB) as a cationic surfactant is a promising adsorbent for removal of humic acid.