钙钛锆石玻璃陶瓷体的晶化和抗浸出性能

以SiO2、A12O3、B2O3、CaO、TiO2和ZrO2为原料，加入3％CeO2（质量分数，下同）作为模拟核素，利用熔融法制备钙钛锆石基玻璃陶瓷体，对含锕系元素的放射性废物进行固化处置。通过X射线衍射仪和场发射扫描电子显微镜等对热处理后玻璃陶瓷体进行表征。以电感耦合等离子体质谱测试玻璃陶瓷体抗浸出性能。结果表明：在晶化温度为1050℃，B203掺量为12．5％时，玻璃陶瓷体中低质量分数的TiO2和ZrO2更易参与生成钙钛锆石晶体，但固化体中仍有其他晶相存在；在同样晶化温度下，B203掺量为8．33％时对玻璃陶瓷体形成钙钛锆石单一晶相较为有利，且具有较好的抗浸出性能，其中Ce在产品一致性测试法下元素标准化浸出率7d后维持在10^-6数量级，固化效果明显。

Crystallization and Leaching Resistance Performance of Zirconolite-Based Glass-Ceramics

The zirconolite-based glass-ceramics were prepared with SiO 2 , Al 2 O 3 , B 2 O 3 , CaO, TiO 2 and ZrO 2 as raw materials and CeO 2 of 3% (in mass fraction, the same below) as simulated nuclide by a melting method for the disposal of actinides-containing radioactive waste solidification. The glass-ceramics obtained after heat treatments were characterized by X-ray diffraction and field emission scanning electron microscopy, respectively. The leaching resistance performance of glass-ceramics was analyzed via inductively coupled plasma mass spectra. The results show that the zirconolite crystals in the glass-ceramics could be more readily formed by lower mass fraction of TiO2 and ZrO2 at B2O3 of 12.5%. Single crystalline phase of zirconolite could be easily formed at the same crystallization temperature and with 8.33% B2O3 , and the glass-ceramics had better leaching resistance performances, its normalized leaching rate of Ce remained at 10 –6 of magnitude after 7 d with the product consistency test method, and the curing effect was obvious.