Study of simulated HLW-glass leaching behavior under low oxygen repository condition

Many countries have recognized vitrification as the suitable solidification method for conditioning high level radioactive waste before they are isolated from biosphere in geologic disposal. This paper studies the leaching behavior of a simulated HLW-glass (90Nd/10) under low oxygen repository condition during 1.5 years. The leaching results showed that the glass was corroded less under low oxygen condition than under ambient atmosphere. XRD analyses showed some little diffraction peak appeared on the leached glass surface at 150 deg. C. At the same time, no diffraction peak appeared on the leached glass surface at 90 deg. C. The secondary products formed on the surface of the leached glass contained mainly Si, Al, Ca and Fe. (author)