Abstract: Uranyl ion imprinted polymer beads were prepared by the copolymerization of styrene monomer and divinyl benzene as crosslinking agent in methanol solution, with the UO22+-o-dihydroxybenzene -4-vinyl pyridine ternary complex as template, the 2,2'-azo-bis-isobutyronitrile as initiator and UO22+ as the imprinting ion. The uranyl ions were removed from the polymer beads by treating with 6 mol/L HCl, leaving behind cavities that match uranyl ion in size. The treated polymer beads can preconcentrate uranyl ions from dilute aqueous solutions. The adsorption efficiency can reach 99% or above with good selectivity when pH is in the range of 5-7 and the adsorption time is more than 20 min. The elution rate can reach above 99% under the conditions of concentration of HCl being above 1.0 mol/L, elution time more than 20 min and the elution volume more than 5 times the volume of ion imprinted polymer. The uranyl ion imprinted polymer beads have been successfully applied to determine micro-uranium in brine samples. The results are satisfactory compared with NBS method.
Template and target information: uranyl ion, UO22+-o-dihydroxybenzene-4-vinyl pyridine ternary complex
Author keywords: uranyl ion, Ternary complex, ion imprinting, polymer, brine