Kinetic behavior of lightly crosslinked chelating resins containing amidoxime groups for batchwise adsorption of uo22+

Lightly crosslinked poly(acrylonitrile-co-divinylbenzene) beads (RN-5) have been synthesized by suspension polymerization. The use of dichloroethane and chloroform as a porogen produced lightly crosslinked copolymer beads having highly porous structures. The chelating resins containing amidoxime groups (RNH-5) have been prepared by the reaction of copolymer beads with NH2OH in MeOH. The resulting chelating resins have been used in the batchwise adsorption of UO22+ from nitrate solutions containing 0.01 mol.dm-3 UO22+ at pH 3.25. In order to get some measure of the relative performance of each resin in kinetic terms, the extraction of UO22+ was monitored with time and some adsorption profiles were obtained. An increase in porogen content resulted in a marked increase in the batchwise adsorption of UO22+. Alkaline treatment allowed a high swelling and hence rapid accessibility of UO22+ to the ligands. Even after 30 minutes, the alkali-treated resins were 50% loaded. © 1993, Taylor & Francis Group, LLC. All rights reserved.