Development of crosslinked chitosan membrane networks for uptake of copper and nickel metal ions

Abstract

Novel chitosan membranes crosslinked with glutaraldehyde, oxalic acid, and succinic acid were synthesized and analyzed as a sorbent for removing copper (Cu 2+ ) and nickel (Ni 2+ ) ions. In the present study, the sorption behavior with respect to initial metal ion concentration and contact time has been investigated. The obtained results clearly indicate that with an increase in the contact time the concentration of metal ions increases while uptake of metal ions decreases simultaneously. From the kinetic studies carried out using Langmuir isotherm model, the maximum adsorption of 0.46 and 0.99 mM/g has been observed in case of chitosan membrane crosslinked with glutaraldehyde for a contact time of 2 h for Cu 2+ and Ni 2+ ions respectively. However, in case of Freundlich isotherms, the Freundlich constant and relative adsorption capacity were found to be maximum in case of chitosan crosslinked with succinic acid and oxalic acid with a contact time of 6 h for Cu 2+ and Ni 2+ ions respectively.