Abstract

Recovery of Water from Heavy Metals using Chelating Chemically Modified� Chitosan

Author(s): H. H. Abdel-Razik and H. A. Almahy

Graft copolymerization of diaminomaleonitrile onto chitosan using ceric ammonium nitrate (CAN) as initiator under N2 atmosphere has been accomplished. Optimum conditions for grafting were as follows: monomer concentration [DAMN] = 1.6 M, [CAN] = 5 x 10−2 mol/L, T = 70ºC and t = 3 hr for 0.5 g chitosan. The imparted cyano groups of the grafted chitosan polymer chains (with degree of grafting up to 84%) were converted into amidoxime groups by the reaction with hydroxylamine hydrochloride. The complexation ability of amidoximated DAMN-graft-chitosan copolymer was investigated with respect to the adsorption of Pb2+, Cd2+, Zn2+, Fe3+, Cu2+, Ni2+ and Co2+ from aqueous solution. The results show that the recoveries of the metals are ~ 93%.