模拟镧系元素固化的掺La_(2)O_(3)玄武岩玻璃的结构与性能研究  

Study on Structure and Properties of La_(2)O_(3)-doped Basaltic Glasses for Immobilizing Simulated Lanthanides

作　　者：童钦 霍冀川 张行泉[1,4] 霍泳霖 徐冲 蒋勤 宋巍伟 TONG Qin;HUO Jichuan;ZHANG Xingquan;HUO Yonglin;XU Chong;JIANG Qin;SONG Weiwei(State Key Laboratory of Environment-friendly Energy Materials,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Electromechanic Engineering College,Mianyang Teachers’College,Mianyang 621000,Sichuan,China;School of Materials and Chemistry,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Analysis and Testing Center,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China)

机构地区：[1]西南科技大学环境友好能源材料国家重点实验室,四川绵阳621010 [2]绵阳师范学院机电工程学院,四川绵阳621000 [3]西南科技大学材料与化学学院,四川绵阳621010 [4]西南科技大学分析测试中心,四川绵阳621010

出　　处：《材料导报》2023年第24期147-151,共5页Materials Reports

基　　金：环境友好能源材料国家重点实验室资助项目(20fksy08);四川省先进材料重大科技专项项目(2019ZDZX0023)。

摘　　要：以玄武岩玻璃为基体,使用La元素模拟高水平放射性废物(HLW)中的核素U,采用熔融-热处理的方法制备掺La_(2)O_(3)玄武岩玻璃固化体,研究了不同La_(2)O_(3)含量的玻璃固化体的结构、热稳定性和抗浸出性能的变化。XRD和SEM分析表明,当La_(2)O_(3)含量增加到12%(质量分数)时,所得样品均表现为玻璃相。Raman分析表明,随着La_(2)O_(3)的加入,玻璃网络中多元环和四元环的Si-O-Si键断裂,Al^(3+)反而会更多地参与网络连接,并且La_(2)O_(3)的加入有助于提高玻璃网络的聚合度。根据DSC分析可知,随着La_(2)O_(3)含量的增加,玻璃固化体的结构刚性提高,热稳定性总体来说有所增强。采用产品一致性试验法(Product consistency test, PCT)计算样品的归一化浸出率,结果表明所有样品都具有较好的化学稳定性,La和Fe的浸出率比其他元素低三个数量级。其中,浸出28 d后,样品L12的La元素归一化浸出率最低。The La_(2)O_(3)-doped basaltic glass was prepared by the solid-state melt method,which the La element is used to simulate the nuclide U in high-level radioactive waste(HLW).The structure,thermal stability and leaching resistance of basaltic glass with different content of La_(2)O_(3) were studied.XRD and SEM results show that all the samples are glassy until the content of La_(2)O_(3) up to 12wt%.Raman results indicate that the addition of La_(2)O_(3) breaks the Si-O-Si bond of large-membered and four-membered in basaltic glass,but more Al 3+participated in the network connection,resulting in the improvement of the polymerization degree of glass network.DSC results show the rigidity and the thermal stability of basaltic glass increases with the increase of La_(2)O_(3) content.The aqueous durability of samples was evaluated by the ASTM product consistency test(PCT)method,which shows that all the samples have good leaching resistance,the leaching rates of La in sample L12 is the lowest after 28 days of leaching,and the leaching rates of La and Fe are three orders of magnitude lower than those of the other elements.

关 键 词：La_(2)O_(3) 玄武岩玻璃 高水平放射性废物 PCT 

分 类 号：TL941.33[核科学技术—辐射防护及环境保护]