Ion-Exchange Separation of ⁶⁰Co and ¹²⁵Sb from Zirconium for Radioactive Waste Management

The feasibility of using ion-exchange resins to separate cobalt and antimony from zirconium in acid solutions was investigated. The distribution coefficients of zirconium, cobalt, and antimony on strong cation and anion exchangers in HCl and oxalic acid media were determined. The mass effect of zirconium on the distribution coefficients of cobalt and antimony was studied. The isotherm for zirconium was obtained in HCl solution. The distribution coefficient and isotherm data were used to develop ion-exchange processes for separation of cobalt and antimony from zirconium in the linear and nonlinear regions of the isotherm. A decontamination factor of more than 10³ was achieved in a single ion-exchange cycle with respect to both cobalt and antimony. Two cycles of ion exchange will bring down the activity to acceptable levels for processing of irradiated zirconium as well as achieve a significant reduction in the waste volume. This is the first paper on separation of ⁶⁰Co and ¹²⁵Sb from zirconium for radioactive waste management.