SUN Ya-ping, CHU Jian, ZHANG Ming*, WANG Xu, WANG Hong-long, WANG Yong-peng, BAI Bin

(Institute of Materials, China Academy of Engineering Physics, Jiangyou 621907, China)

Abstract: As the second-generation candidate materials for immobilizing high level radioactive-wastes (HLW), mineral hosts have good thermal stability, chemical stability and irradiation stability. However, as most mineral hosts which were currently used to study their chemical stabilities contain little radionuclides, or inadequately accumulated irradiation damage defects, they can hardly to reflect the real behavior of radioactive-waste hosts in geological disposal facilities (GDF). In addition, it is very difficult to simulate the long-term (10 000－100 000 years) physical and chemical conditions of the GDF for dealing with the HLW in the laboratory. Some natural radionuclide-bearing minerals still maintain stable compositions and crystal forms after millions even billions of years of geological processes. Their structures due to the self-irradiation are similar to those of the radionuclide-bearing mineral hosts. In this paper, a comparative study has been carried out on the similarities and differences of hydrothermal alteration between the natural minerals and HLW hosts, on the basis of reviews of the research status of the hydrothermal alteration of natural minerals through a large number of literature investigation, in order to provide scientific basis and evaluation data for researches on the long-term chemical stability of the HLW mineral hosts.

Keywords: Radioactive waste mineral host; natural mineral; chemical stability; hydrothermal alteration

ACTA MINERALOGICA SINICA Vol. 39, No.3, 2019, page 311-319