Phase evolution, solubility and substitution behavior of CaZrTi2O7-Ho2Ti2O7 ceramics for potential nuclear waste immobilization

被引：0

作者：

Ji, Xiuhua ^{[1
,2
]}

Song, Yanhao ^{[1
,2
]}

Wang, Jiarun ^{[2
]}

Ding, Yi ^{[2
]}

Ji, Shiyin ^{[1
,2
,3
]}

Duan, Tao ^{[1
,3
,4
]}

机构：

[1] Southwest Univ Sci & Technol, Tianfu Inst Res & Innovat, Chengdu 610299, Peoples R China

[2] Southwest Univ Sci & Technol, Sch Natl Def Sci & Technol, Mianyang 621010, Peoples R China

[3] Southwest Univ Sci & Technol, Natl Coinnovat Ctr Nucl Waste Disposal & Environm, Mianyang 621010, Peoples R China

[4] Southwest Univ Sci & Technol, State Key Lab Environm Friendly Energy Mat, Mianyang 621010, Peoples R China

来源：

CERAMICS INTERNATIONAL | 2024年 / 50卷 / 24期

基金：

中国国家自然科学基金;

关键词：

Zirconolite; Pyrochlore; Substitution mechanism; Phase evolution; Minor actinides; GLASS-CERAMICS; RARE-EARTH; ZIRCONOLITE; GD; ND; CRYSTALLIZATION; MICROSTRUCTURE; A(2)B(2)O(7); DIFFRACTION; SYSTEM;

D O I：

10.1016/j.ceramint.2024.10.392

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Zirconolite and pyrochlore have been considered as the potential immobilization matrix materials of minor actinides due to their high solubility, radiation tolerance and chemical durability. In this work, a series of xHo2xZr1-xTi2O7 (0.1 <= x <= 1.0) ceramics were prepared by solid state synthesis and sintering at 1400 degrees C for twice. Powder X-ray Diffraction (XRD), Backscattered Scanning Electron Microscopy with Energy-Dispersive ray spectroscopy (BSEM-EDX), Transmission Electron Microscopy (TEM) were employed to investigate the phase evolution, solubility, and substitution mechanism of Ho. The results displayed that zirconolite-2M would transformed to zirconolite-4M and then to pyrochlore with increasing Ho concentration. The initial phase transformation of zirconolite-2M to zirconolite-4M, subsequently zirconolite-4M to pyrochlore were observed x = 0.2 and 0.4 samples, respectively. Zirconolite-4M could be synthesised at x = 0.38 sample with trace perovskite. Moreover, the semi-quantitively solubility limits of Ho in zirconolite-2M and zirconolite-4M were determined to be 27 and 41.5 at.%, respectively. Single-phase pyrochlore were fabricated after 70 at.%. addition, the novel substitution mechanism was revealed by Rietveld refinement with Ho preferentially replacing the Ca of zirconolite-2M so that some replaced Ca occupied vacant Zr site. For pyrochlore, Ho, Ca and occupied A site (16d) and Ti entered in B site (16c). The findings would provide more insights into zirconolite-pyrochlore ceramic system.

引用

页码：55342 / 55350

页数：9

共 46 条

[1]

Donald I.W., Metcalfe B.L., Taylor R.N.J., The immobilization of high level radioactive wastes using ceramics and glasses, J. Mater. Sci., 32, pp. 5851-5887, (1997)

[2]

Yudintsev S.V., Stefanovsky S.V., Ewing R.C., Actinide host phases as radioactive waste forms, Structural Chemistry of Inorganic Actinide Compounds, pp. 457-490, (2007)

[3]

Gin S., Abdelouas A., Criscenti L.J., Ebert W.L., Ferrand K., Geisler T., Harrison M.T., Inagaki Y., Mitsui S., Mueller K.T., Marra J.C., Pantano C.G., Pierce E.M., Ryan J.V., Schofield J.M., Steefel C.I., Vienna J.D., An international initiative on long-term behavior of high-level nuclear waste glass, Mater. Today, 16, pp. 243-248, (2013)

[4]

McCloy J.S., Riley B.J., Crum J., Marcial J., Reiser J.T., Kruska K., Peterson J.A., Neuville D.R., Patil D.S., Saleh M., Barnsley K.E., Hanna J.V., Crystallization study of rare earth and molybdenum containing nuclear waste glass ceramics, J. Am. Ceram. Soc., 102, pp. 5149-5163, (2019)

[5]

Singh B.K., Hafeez M.A., Kim H., Hong S., Kang J., Um W., Inorganic waste forms for efficient immobilization of radionuclides, ACS ES&T Eng., 1, pp. 1149-1170, (2021)

[6]

Li H., Wu L., Xu D., Wang X., Teng Y., Li Y., Structure and chemical durability of barium borosilicate glass-ceramics containing zirconolite and titanite crystalline phases, J. Nucl. Mater., 466, pp. 484-490, (2015)

[7]

Yu H., Xin R., Zhang X., Liu H., Zheng K., Zhao J., Zhan L., Xu C., Wan W., Zhu Y., Huo J., Crystallization behavior, quantitation of Ce<sup>3+</sup>/Ce<sup>4+</sup> and chemical stability analysis of multiple alkaline earths borosilicate glasses for immobilizing simulated tetravalent actinides, J. Non-Cryst. Solids, 558, (2021)

[8]

Ojovan M.I., Lee W.E., Glassy wasteforms for nuclear waste immobilization, Metall. Mater. Trans. A, 42, pp. 837-851, (2011)

[9]

Ringwood A.E., Kesson S.E., Ware N.G., Hibberson W., Major A., Immobilisation of high level nuclear reactor wastes in SYNROC, Nature, 278, pp. 219-223, (1979)

[10]

Matzke H., Ray I.L.F., Seatonberry B.W., Thiele H., Trisoglio C., Walker C.T., White T.J., Incorporation of transuranic elements in titanate nuclear waste ceramics, J. Am. Ceram. Soc., 73, pp. 370-378, (1990)

← 1 2 3 4 5 →