Sorption properties of phosphoric acid cationites in regard to uranyl ions

A study is made on sorption properties of KF-7 cationite (based on copolymer of vinyl phosphonic acid with divinylbenzene) and KFP-12-1 cationite based on copolymer of benzyl styrene with divinylbenzene of the gel- and macroporous nature in regard to uranyl ions. Sorption was conducted from hydrochloric acid and carbonate solutions with different pH values. The sorption of uranyl ions is shown to increase with pH growth due to increase in dissociated phosphonic groups capable of ion exchange. Relatively high values of the apparent H+-UO22+ exchange constants testify to simultaneous procedure of the ion exchange and complex formation. A possible mechanism of the process is suggested