MECHANISM OF ISOTOPIC EXCHANGE FOR CS+ ASTERISK-CS+, SR2+/ASTERISK-SR2+, AND CO2+/ASTERISK-CO2+ ON CERIUM(IV) AND TIN(IV) ANTIMONATES PARTICLES/

Self-diffusion coefficients ((D) over bar)$ for Cs+, Sr2+, and Co2+ io ns in cerium(IV) antimonate and tin(IV) antimonate have been investiga ted under conditions of particle diffusion and the limited batch techn ique for these ions in solutions of different acidity. The effect of h eat treatment on the rate of isotopic exchange reactions on both mater ials was also studied. Values for the diffusion coefficients, activati on energy, and entropy of activation have been evaluated. The data obt ained have been compared with those reported for other organic and ino rganic exchangers, which give some information regarding the mechanism of ion exchange on the surface of the ion exchange materials.