Combustion synthesis and characterizations of Sm2O3 doped zirconolite-rich waste forms with CuO as oxidant  

作　　者：Kuibao Zhang Dan Yin Zongsheng He Jiali Xue Wenwen Zhao Haibin Zhang 

机构地区：[1]State Key Laboratory of Environment-friendly Energy Materials,Southwest University of Science and Technology,Mianyang 621010,China [2]National Defense Key Discipline Lab of Nuclear Waste and Environmental Safety,Southwest University of Science and Technology,Mianyang 62W10,China [3]Institute of Nuclear Physics and Chemistry,China Academy of Engineering Physics,Mianyang 621900,China

出　　处：《Journal of Rare Earths》2019年第12期1359-1365,共7页稀土学报（英文版）

基　　金：Projects supported by the National Natural Science Foundation of China(51202203,51672228);the Project of State Key Laboratory of Environment-friendly Energy Materials(17FKSY0104);Science Development Foundation of China Academy of Engineering Physics

摘　　要：Zirconolite is one of the most important matrix materials for nuclear waste immobilization.In this study,Sm was employed as the surrogate of trivalent actinides.Sm-doped zirconolite-rich waste forms were readily prepared by combustion synthesis(CS)using CuO as the oxidant.Two different schemes with or without Al2O3 as the charge compensator were carried out simultaneously.The results demonstrate that Al2O3 addition results in complex phase composition.On the other hand,the samples without Al2O3 addition show desirable products of zirconolite and pyrochlore.The EDX analysis shows that Sm is concurrently incorporated into the Ca and Zr sites of zirconolite,which transforms to pyrochlore structure with high Sm2O3 contents.The aqueous durability of representative Sm-doped sample(Sm-0.6)was investigated.The 42 days normalized leaching rate of Sm is as low as 6.41×10-7 g/(m2 d),which exhibits high durability of Sm-doped sample.Zirconolite is one of the most important matrix materials for nuclear waste immobilization.In this study,Sm was employed as the surrogate of trivalent actinides.Sm-doped zirconolite-rich waste forms were readily prepared by combustion synthesis（CS） using CuO as the oxidant.Two different schemes with or without Al2O3 as the charge compensator were carried out simultaneously.The results demonstrate that Al2 O3 addition results in complex phase composition.On the other hand,the samples without Al2O3 addition show desirable products of zirconolite and pyrochlore.The EDX analysis shows that Sm is concurrently incorporated into the Ca and Zr sites of zirconolite,which transforms to pyrochlore structure with high Sm2O3 contents.The aqueous durability of representative Sm-doped sample（Sm-0.6）was investigated.The 42 days normalized leaching rate of Sm is as low as 6.41×10-7 g/（m2 d）,which exhibits high durability of Sm-doped sample.

关 键 词：COMBUSTION synthesis SM2O3 ZIRCONOLITE PYROCHLORE Aqueous durability RARE earths 

分 类 号：O61[理学—无机化学]