An imprinted polymer for removal of Cd2+ from water samples: Optimization of adsorption and recovery steps by experimental design

Abstract

A new ion-imprinted polymer (IIP) was synthesized by copolymerization of 4-vinylpyridine (monomer), ethyleneglycoldimethacrylate (cross-linker) and 2,2-azobis-isobutyronitrile (initiator) in the presence of Cd2+ and quinaldic acid (complexing agent). It was found that the adsorption capacity of IIP and blank polymer were 45.0 and 6.2 mg g−1, respectively. The relative selectivity coefficients of the imprinted polymer for different binary mixture were also calculated. Compared to non-imprinted polymer (NIP), the IIP had higher selectivity for Cd(II). The IIP was used as a sorbent for cadmium extraction from water samples by using a simple batch extraction procedure. The effect of different parameters on Cd2+ extraction and its recovery from the IIP were evaluated and optimized by using experimental design methodology. The optimized adsorption/desorption procedure was applied for cadmium removal from the real water samples. The obtained recoveries proved that this IIP could be used for removal of trace cadmium ions from water samples.