Tc immobilization by using perovskite-rich and rutile-rich synroc  

作　　者：ZHANGChuan-Zhi LIBao-Jun LUOShang-Geng 

机构地区：[1]ChinalnitituteofAtomicEnergy,Beijing102413

出　　处：《Nuclear Science and Techniques》2005年第2期114-116,共3页核技术（英文）

基　　金：This work is one part of Research Coordination Program of International Atomic Energy Agency(No.10637)

摘　　要：The simulating technetium (Tc) separated from HLW was immobilized in perovskite-rich and rutile-rich synroc which contained 85wt% of perovskite or rutile, and 20, 25, 30 or 35wt% waste loading, respectively. The synroc was prepared by hot pressing under reducing condition. The fabricated samples have good physical properties (density and open porosity). The XRD analyses show that the major phase is perovskite or rutile and the minor phases are zirconolite, hollandite and metal alloy. At higher waste loading the metal alloy phase appeared, particularly in the rutile-rich synroc. The scanning electron microscopy (SEM) and backscattered electron images (BEI) show the samples to be homogeneous and densified. The MCC-1 leaching tests (90℃, 28 d) results show that: mass losses are at the level of 10-3 G·m-2·d-1,and the nominal element leaching rates are 10-5-10-3 G·m-2·d-1.It indicates that the fabricated samples have good leach resistance. According to their physical properties and leach resistance, the perovskite-rich and rutile-rich synroc can immobilize Tc up to 35 wt%. In comparison, Tc immobilization by using perovskite-rich synroc is more favorable.The simulating technetium (Tc) separated from HLW was immobilized in perovskite-rich and rutile-rich synroc which contained 85wt% of perovskite or rutile, and 20, 25, 30 or 35wt% waste loading, respectively. The synroc was prepared by hot pressing under reducing condition. The fabricated samples have good physical properties (density and open porosity). The XRD analyses show that the major phase is perovskite or rutile and the minor phases are zirconolite, hollandite and metal alloy. At higher waste loading the metal alloy phase appeared, particularly in the rutile-rich synroc. The scanning electron microscopy (SEM) and backscattered electron images (BEI) show the sam- ples to be homogeneous and densified. The MCC-1 leaching tests (90℃, 28 d) results show that: mass losses are at the level of 10-3 g?m-2?d-1, and the nominal element leaching rates are 10-5~10-3 g?m-2?d-1. It indicates that the fabri- cated samples have good leach resistance. According to their physical properties and leach resistance, the perovskite-rich and rutile-rich synroc can immobilize Tc up to 35 wt%. In comparison, Tc immobilization by using perovskite-rich synroc is more favorable.

关 键 词：钙钛矿 合成岩 金红石 放射性废弃物 锝 

分 类 号：TL94[核科学技术—辐射防护及环境保护]