Ep. Horwitz et al., UPTAKE OF METAL-IONS BY A NEW CHELATING ION-EXCHANGE RESIN .1. ACID DEPENDENCIES OF ACTINIDE IONS, Solvent extraction and ion exchange, 11(5), 1993, pp. 943-966
The uptake of several actinide ions [U(VI), Pu(IV), Np(IV), Th(IV] and
Am(III)) from nitric and hydrochloric acid solutions, and of U(VI) fr
om near-neutral solutions by the new chelating ion-exchange resin, Dip
honix(TM), has been investigated. Diphonix is a polyfunctional resin c
ontaining sulfonic and gem-disphosphonic acid groups chemically bonded
in a styrene-divinylbenzene polymeric network. Comparison of the acid
dependencies of the actinide ions uptake measured with Diphonix with
those obtained using a commercial sulfonic-type resin and a resin cont
aining both sulfonic and monophosphonic acid groups, has shown that Di
phonix binds the actinides via a different kind of chemical interactio
n, involving the,formation of chelate complexes through the phosphoryl
groups of the gem-diphosphonic acids. As a consequence, Diphonix is s
uperior to other resins in extracting actinide ions from very acidic s
olutions. A better performance of Diphonix is also observed with the u
ptake of uranium from neutral solutions. Conditions for efficient stri
pping of actinide species from the resin have been found.