Abstract: AbstractA new Th(IV) ion-imprinted polymer (IIP) was synthesized for the separation and recovery of trace Th(IV) ion from river water sample. Th(IV) IIP was prepared by copolymerization of methyl methacrylate (monomer) and ethylene glycol dimethacrylate (cross-linker) in the presence of Th(IV)-thiosemicarbazide-4-vinyl pyridine ternary complex wherein Th(IV) ion is the imprint ion and is used to form the imprinted polymer. Thorium(IV) ion was eluted with 10 mL of 1 M HCl. The polymers have been characterized by surface area measurements, fourier transform infrared spectroscopy, microanalysis and scanning electron microscopy analysis. The adsorption capacity of the imprinted polymer was found to be 0.290 mmol g-1, which is much higher than most of the reported IIPs. The optimum pH for quantitative enrichment is 4.0. The relative selectivity coefficient values of the imprinted polymer for Th(IV)/Pb(II), Th(IV)/Zn(II), Th(IV)/Cu(II), Th(IV)/Ni(II), Th(IV)/Cd(II) and Th(IV)/Co(II) are 37.13, 37.40, 30.34, 35.69, 37.63 and 36.28, respectively. The lowest concentration that could be determined by Arsenazo III spectrophotometric method below which the recovery becomes non-quantitative is 5 μg L-1
Author keywords: Thorium(IV), ICP-MS, Ion-imprinted polymer, Arsenazo III, Thiosemicarbazide