Yacouba Sanou - Laboratory of Analytical, Environmental and Bio-Organic Chemistry (LCAEBiO), University of Ouaga I, Professor Joseph KI-ZERBO, URF/SEA, Chemistry Department, ۰۳ BP ۷۰۲۱ Ouagadougou ۰۳. Burkina Faso
Nguyen Thi Thanh Phuong - Institute for Environment and Resources (IER/ HCMC), Vietnam National University, Vietnam.
Nguyen Van Phuoc - Institute for Environment and Resources (IER/ HCMC), Vietnam National University, Vietnam.

This work aims to study the As (V) removal in aqueous solutions using Granular Ferric Hydroxide (GFH) and Natural Laterite at ambient temperature. Column experiments were conducted to investigate the As (V) removal mechanism and effects of parameters affecting the adsorption were studied to follow the adsorption kinetics. Maximum removal of arsenic (99.99% and 99.5%) was achieved at 15 min of contact time with an initial concentration of 20 mg/L using 10 g of GFH and laterite in 50 ml volume of solution, respectively. From the isotherm models study, i.e. Langmuir, Freundlich and Dubinin - Radushkevich, the adsorption process in our study followed best Freundlich isotherm. The study of isotherms showed that the adsorption was physical, spontaneous with GFH while endothermic using laterite, respectively. The kinetics study showed that the adsorption process fits with a pseudo-second order reaction model using both adsorbents. The adsorption column design was done using Logit method and the obtained values of adsorption rate coefficient (K) and adsorption capacity coefficient (N) were 3.2 10-4 L/(mg. min) and 8968.46 mg/L, respectively for GFH and 1.43 10-3 L/(mg. min), 977.19 mg/L using laterite. The fixed bed column studies showed that Granular Ferric Hydroxide and Laterite were efficient in small-scale for As (V) removal.

Arsenic, Removal, Granular Ferric Hydroxide, Laterite, aqueous solutions