KINETIC-BEHAVIOR OF LIGHTLY CROSS-LINKED CHELATING RESINS CONTAINING AMIDOXIME GROUPS FOR BATCHWISE ADSORPTION OF UO2(2+)

Lightly crosslinked poly(acrylonitrile-co-divinylbenzene) beads (RN-5) have been synthesized by suspension polymerization. The use of dichlo roethane and chloroform as a porogen produced lightly crosslinked copo lymer beads having highly porous structures. The chelating resins cont aining amidoxime groups (RNH-5) have been prepared by the reaction of copolymer beads with NH2OH in MeOH. The resulting chelating resins hav e been used in the batchwise adsorption of UO22+ from nitrate solution s containing 0.01 mol.dm-3 UO22+ at pH 3.25. In order to get some meas ure of the relative performance of each resin in kinetic terms, the ex traction of UO22+ was monitored with time and some adsorption profiles were obtained. An increase in porogen content resulted in a marked in crease in the batchwise adsorption of UO22+. Alkaline treatment allowe d a high swelling and hence rapid accessibility of UO22+ to the ligand s. Even after 30 minutes, the alkali-treated resins were 50% loaded.