Adsorption of 60Co and 154+152Eu using graft copolymer of starch-polyacrylic acid-polyvinylsulfonic acid

Abstract

Graft copolymer of starch-polyacrylic acid-polyvinylsulfonic acid (St-g-PAA-PVSA) was synthesized by gamma radiation as an initiator. The chemical structure, morphology, and thermal stability of the graft copolymer were investigated using FTIR, SEM, and TGA. St-g-PAA-PVSA graft copolymer was employed as an adsorbent for the removal of cobalt(II) and europium(III) radionuclides from their aqueous solutions by batch adsorption method. Several experimental factors such as pH, contact time, initial concentration of adsorbate, and temperature were used to find the best conditions for the removal of cobalt(II) and europium(III) radionuclides. The pseudo-second order kinetic model better fit the adsorption kinetic data of radionuclides. Langmuir models had the ability to well describe the equilibrium data of adsorption of radionuclides. Thermodynamic parameters were calculated and suggested the adsorption process was endothermic and spontaneous in nature. Among the examined desorbing agents, both AlCl3 and HCl were succeeded to desorb most of radionuclides.