UPTAKE OF METAL-IONS BY A NEW CHELATING ION-EXCHANGE RESIN .9. SILICAGRAFTED DIPHOSPHONIC ACID

A new chelating ion exchange resin, Diphonix(R), containing geminally substituted diphosphonic acid ligands bonded to a styrene-based polyme ric matrix, was recently developed and characterized. To overcome some of the problems associated with the stripping of actinide elements fr om the resin, a new version of the Diphonix resin has been prepared, w here the chelating diphosphonic acid groups are grafted to a silica su pport. The new material is called Diphosil, for Diphonix on silica. Th e properties of the new material have been investigated with regard to its equilibrium and kinetic behavior in the uptake of actinide and ot her ions from acidic solutions. In this work data comparing the Diphon ix and Diphosil resins are presented and discussed. The Diphosil resin appears particularly well suited for those cases where the recovery a nd further processing of the sorbed actinides is not required and the loaded resin can be considered as a solid waste. Because about 90 % of the Diphosil resin weight is silica, the problem of possible generati on of gaseous compounds due to the slow radiolytical degradation of th e organic components of the resin is minimized.