Removal of trivalent and pentavalent arsenic from water using chemically modified chitosan beads

Abstract

A novel process for chemical modification of chitosan with iron oxide and potassium permanganate was developed and the beads of the modified material have been prepared for the removal of the two forms of the metalloid Arsenic - As(III) and As(V)from water in the concentration range 5-40 mg L-1. The maximum adsorption capacity (pH 7.0) is 43.28 and 32.26 mg g-1 for As(III) and As(V), respectively. The chemically modified chitosan beads are regenerated for successive treatment cycles through alkali treatment. The regenerated beads show negligible loss in their removal efficiency of As(III) and As(V). Overall, the study provides a novel process for fabrication of low-cost composite material of chitosan for enhanced removal of Arsenic. This report will facilitate the development and up-scaling of low-cost treatment technologies for adsorptive removal of Arsenic from water.