ZEOLITES FOR NUCLEAR WASTE TREATMENT - CO, NI, ZN UPTAKE INTO SYNTHETIC FAUJASITES X-AND-Y .1. PH EFFECTS, CALCINATION, ELUTION AND ENCAPSULATION STUDIES

Synthetic zeolites X & Y have been examined for their abilities to take in Co, Ni and Zn radioisotopes. Distribution coefficients (K(d)) have been determined, with and without competing cations, and at various pH values. Elution studies on zeolites containing Co, Ni and Zn radioisotopes considered the effect of acid and alkaline conditions, calcination and cement encapsulation. Leach rates arising from these experiments have been calculated. The general conclusions can be drawn are that zeolites X & Y are suitable for decontamination of aqueous wastes containing Co, Ni and Zn. Cement encapsulation is appropriate but no advantage accrues from pre-calcination. Some comments on the likely mechanism of leaching losses have been made.