高庙子天然钙基膨润土和改性钠基膨润土的热和辐射稳定性

Stability of GMZ natural Ca-bentonite and modified Na-bentonite under thermal and electron irradiation aging

为了筛选高放废物深地质处置库中适用的缓冲材料,以内蒙古高庙子天然钙基膨润土和由其改性制备的钠基膨润土为研究对象,分别在120℃、150℃、180℃下热老化3000h、6000h和9000h,用电子加速器在室温下进行了辐射老化,累计辐照剂量分别为1000kGy、3000kGy和5000kGy,随后对老化前后的样品用X射线衍射仪进行了分析测量。结果表明:高庙子改性钠基膨润土的高温长期热稳定性比其天然钙基膨润土好,改性钠基膨润土在大剂量率电子辐射作用下的稳定性也比其天然钙基膨润土好;因此宜选择改性钠基膨润土或者天然钠基膨润土作为处置库的缓冲材料。

In order to select suitable buffer material for geological disposal repository, natural Ca-bentonite and modified Na-bentonite,from Gaomiaozi（GMZ）, Inner Mongolia,were studied by thermal aging at 120℃, 150℃ and 180℃ for 3000h,6000h and 9000h, also by electron irradiation aging at room temperature to 1000kGy, 3000kGy and 5000kGy. The samples before and after aging were analyzed by X-ray diffractometer. The results showed that modified Na-bentonite was more stable than natural Ca-bentonite during both thermal aging and electron irradiation aging, so it was appropriate to choose natural Na-bentonite or modified Na-bentonite as buffer material.