Effect of the preparation conditions of zirconium phosphate on the characteristics of Sr immobilization

The proton-type crystalline zirconium phosphate, HZr2(PO4)3, was obtained by a thermal decomposition of NH4Zr2(PO4)3 at different temperatures from 400 to 800 °C, where NH4Zr2(PO4)3 was obtained in advance by a hydrothermal synthesis using a mixed solution of ZrOCl2, H3PO4 and H2C2O4 with different processing times from 5 to 72 h. Sr ion was immobilized to HZr2(PO4)3 by treating the mixture of HZr2(PO4)3 and Sr(NO3)2 aqueous solution in an autoclave at 250 °C. Immobilizing and leaching performance of St in HZr2(PO4)3 were discussed.