Hybrid Anion Exchange/Activated Carbon for Cr(VI) Removal in Drinking Water

A novel hybrid anion exchangeable activated carbons (HACAX) is synthesized through chemical modification of porous carbon surface. Ion exchange capacity, kinetics and regeneration tests suggest that HACAX contains stable positive charged functional groups. The surface characterization results suggest HACAX not only contains stable positive charged functional groups, but also a broad spectrum of surface oxygen functional groups. In the study of adsorption of hexavalent chromium, HACAX shows excellent kinetics, selectivity and regeneration efficiency towards Cr (VI). Combined with rich surface oxygen functional groups, this material provides a pathway to adsorb and convert Cr(VI) into Cr(III) at natural pH. The results suggest HACAX could potentially provide an effective point-of-use (POU) solution for hexavalent chromium removal from drinking water.