Selective adsorption of U(VI) by using U(VI)- imprinted poly-hydroxyethyl methacrylate- methacryloyl-L-histidine (p-[HEMA-(MAH)3]) cryogel polymer

Abstract

In this study, selective adsorption of U(VI) in aqueous solutions in the presence of various lanthanide ions was conducted by using U(VI)-imprinted cryogel polymer. For this purpose, the pHEMA-(MAH)3-U(VI) cryogel polymer was prepared by free radical polymerization method. U(VI) was desorbed with 5.0 mol.L-1 HNO3 and thus U(VI)-imprints were created on p-HEMA-(MAH)3 cryogel polymer. To determine the optimum conditions, in the process of selective adsorption of U(VI) ion to U(VI)-imprinted p-HEMA-(MAH)3 cryogel polymer, some parameters such as pH, flow rate, initial U(VI) concentration were investigated. Under the optimum conditions, the maximum adsorption capacity was obtained as 74.80 mg.g-1. Selectivity studies were also carried out in the presence of Nd(III), La(III) and Y(III) ions using U(VI)-imprinted p-HEMA-(MAH)3 cryogel polymer. The obtained adsorption order under competitive conditions was U(VI) > La(III) > Y(III) > Nd(III).