Radiation synthesis of imprinted hydrogels for selective metal ions adsorption

Abstract

In this study, the imprinted hydrogels were prepared to remove cobalt and lead metal ions from wastewater with high selectivity. The imprinted hydrogel was prepared by copolymerization of (N-vinyl-2-pyrrolidone) and acrylamide monomers using gamma irradiation in the presence of cobalt or lead metal ions. The complexed ions were completely eluted with 2 M HCl. The control hydrogel was also prepared by similar experimental conditions without using imprinted ions. Both control and imprinted hydrogels were characterized by FT-IR, TGA XRD, and SEM. The effect of various parameters such as pH, time, and initial feed concentration on the extraction efficiency was investigated and compared data with control hydrogels. The pseudo-second-order kinetic model was described well the adsorption, reveals the good accessibility of the chelating sites in the imprinted sorbent for uptake of selected ion. The experimental data are fitted better to the Langmuir model (R² > 0.99) than the Freundlich model. It was found that the imprinted hydrogels were exhibited high affinity toward the template metal ions specially Pb²⁺.

Keywords:

• Gamma-irradiation
• Imprinted
• Hydrogel
• Metal ions
• Selectivity