Separation and extraction of some heavy and toxic metal ions from their wastes by grafted membranes

Preparation and characterization of a series of ion-exchange membranes for the purpose of separation and extraction of some heavy and toxic metal ions from their wastes were studied. Such ion-exchange membranes were prepared by gamma -radiation grafting of acrylonitrile (AN) and vinyl acetate (VAc) in a binary monomer mixture onto low-density polyethylene (LDPE) using the direct technique of grafting. The reaction conditions at which the grafting process proceeds successfully were determined. Many modification treatments were attempted for the prepared membranes to improve their ion-exchange properties. The possibility of their practical use in waste-water treatment to remove some heavy and toxic metal ions such as Pb2+, Cd2+, Cu2+, Fe3+, Sr2+ and Li+ were investigated. These grafted membranes showed great promise for possible use in the field of extraction and removal of some heavy and toxic metals from their wastes. (C) 2001 John Wiley & Sons, Inc.