Nuclear Techniques ›› 2015, Vol. 38 ›› Issue (9): 90301-090301.doi: 10.11889/j.0253-3219.2015.hjs.38.090301


Chemical stability of simulated waste forms SrZrxTi1?xO3

MU Wanjun1 LI Xingliang1 YU Qianhong1 JIAN Yuan1 WEI Hongyuan1 YANG Yushan2   

  1. 1(Institute of Nuclear Chemistry and Physics, China Academy of Engineering Physics, Mianyang 621900, China) 2(College of National Defence, Southwest University of Science and Technology, Mianyang 621900, China)
  • Received:2015-03-30 Revised:2015-06-26 Online:2015-09-10 Published:2015-09-10

Abstract: Background: 90Zr is a decay product of 90Sr, which may induce structural changes of radioactive waster forms. Purpose: In order to study the influence of decay product on the stability of perovskite-type SrTiO3 used for immobilizing 90Zr, C4H6O4Sr?0.5H2O, TiO2 and ZrOCl2?8H2O are used as the starting materials. Methods: The Zr-doped SrTiO3 synthesized can be generally represented as SrZrxTi1?xO3 (0≤x<1) with the high temperature solid reaction. The phases, structure and microcosmic shape of synthetic condensates were characterized by the X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Fourier Transform Infrared (FT-IR), and long-term chemical stability was studied at constant temperature of 90 oC. Results: The results indicate that the second phase of compounds is observed when the value of x is more than 0.5. The leaching rate of Sr2+ and Zr4+ in waste forms increase with the immersion time, while the highest leaching ratios for 42 d are no more than 0.0065 ?g?mL?1 and 0.01?g?mL?1, respectively. The crystalline phase and morphology of solidified SrZrxTi1?xO3 waste form are influenced by electron beam irradiation. Conclusion: This study results may provide technical support for long-time immobilization of the 90Sr.

Key words: Perovskite-type, Waster forms, Leaching behavior, Radiation