Removal of As(V) and As(III) from water with a PEI-modified fungal biomass

Abstract

A novel biosorbent was prepared by chemically grafting polyethylenimine (PEI) on the fungal biomass of Penicillium chrysogenum through a two-step reaction. The PEI-rnodified biomass was found to possess zero zeta potential at pH 10.4. Owing to the protonation of amine groups on the biosorbent surface, the biosorbent is favourable for the removal of anionic arsenic species in water. The sorption capacity for As(V) at pH 3 increased by 5.7-fold after surface modification. The sorption performances including kinetics and isotherm were investigated and several models were used to describe the experimental data. The pseudo-second-order model described the kinetic data better, while the Langmuir equation was the better model to fit the isotherm data. The corresponding thermodynamic parameters for As(V) and As(III) sorption were also calculated. © IWA Publishing 2007.