%A ZHANG Xue, WANG Jin, LUO Ping, LIU Die, ZHAN Lei, WEI Yufeng, WANG Junxia %T Study on Immobilization of Simulated Radionuclide Sr2+/Sm3+ by NZP-type Phosphate Ceramics %0 Journal Article %D 2022 %J Materials Reports %R 10.11896/cldb.20090353 %P 20090353-10 %V 36 %N 1 %U {http://www.mater-rep.com/CN/abstract/article_4582.shtml} %8 2022-01-10 %X In this work, Sr2+ and Sm3+ were chosen as surrogates for the fission nuclide and minor actinides, respectively. NaZr2(PO4)3 (hereinafter referred to as NZP) was employed to simultaneously incorporate the multiple simulated radionuclides due to its abundant ionic substitution, and a series of Sr2+ and Sm3+ incorporated NZP-type (Na, Sr)(Zr, Sm)2(PO4)3 ceramics waste forms were prepared by microwave sintering at 1 100 ℃ holding for 2 h. The effects of Sr/Sm content on the phase composition, micromorphology, apparent density, and Vickers hardness of the samples were systematically investigated. It was shown that Sr was incorporated in the Na lattice of NZP structure to form Sr0.5Zr2(PO4)3 (SrZP), while Sm was difficult to enter Zr lattice site of NZP, but mainly existed in the form of SmPO4 monazite phase. The Sr/Sm-incorporated ceramics waste forms exhibited an excellent dense structure with uniform grain size, and the existence of SmPO4 monazite would not lower its densification and physical properties. The apparent density and Vickers hardness of the samples increased gradually with the increase of Sm content, which were up to 3.61 g·cm-3 and 679 MPa, respectively. Moreover, it was indicated that the as-prepared samples exhibited great chemical stability according to PCT test results, and the normalized leaching rate of each element was in the order of 10-3—10-7 g·m-2·d-1.