Professor, Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science

Speech Title: Adsorptive removal of As(V) from contaminated groundwater using chitosan-coated bentonite: Isotherm, kinetics and thermodynamics

Abstract: In the present work, the adsorption of As(V) from contaminated groundwater with an initial concentration of 50.99 μg/L on chitosan-coated bentonite (CCB) under static conditions was investigated. Equilibrium data was evaluated using isotherm models such as Langmuir, Freundlich, and Dubinin-Radushkevich. Kinetics studies revealed that pseudo-second order equation adequately describes the experimental data (R2 ≥ 0.9951). Thermodynamics show that the As(V) adsorption is spontaneous (ΔG0 ≤ 0), endothermic (ΔH0 = 83,254.12 J/mol•K) and that an increase in the randomness (ΔS0 = 255.33 J/mol) of CCB-solution interface occur during the process. FT-IR analysis reveals that hydroxyl and amino groups are involved in the adsorption of As(V) from groundwater. Results of this study will serve as a tool in determining an environmentally safe and cost effective reactive material in a as a permeable reactive barrier system that will be utilized in the remediation of As(V) contaminated groundwater.