Synthesis of Coffinite, USiO4, and Structural Investigations of UxTh(1-x)SiO4 Solid Solutions

被引:37
作者
Labs, Sabrina [1 ]
Hennig, Christoph [2 ]
Weiss, Stephan [2 ]
Curtius, Hilde [1 ]
Zaenker, Harald [2 ]
Bosbach, Dirk [1 ]
机构
[1] Forschungszentrum Julich GmbH, Nucl Waste Management, Insitute Energy & Climate Res IEK 6, D-54245 Julich, Germany
[2] Helmholtz Zentrum Dresden Rossendorf, Inst Resource Ecol, D-01328 Dresden, Germany
关键词
X-RAY; SI-O; THORITE; URANIUM; ZIRCON; URANINITE; STABILITY; SILICATE; DEPOSIT; FUEL;
D O I
10.1021/es403995b
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
The miscibility behavior of the USiO4-ThSiO4 system was investigated. The end members and 10 solid solutions UxTh(1-x)SiO4 with x = 0.12-0.92 were successfully synthesized, without formation of other secondary uranium or thorium phases. Lattice parameters of the solid solutions evidently follow Vegard's Law. Investigation of the local structure with EXAFS reveals small differences between the U and Th environment attributed to different atomic radii of the metal atoms but no implications for a miscibility gap. The data provided confirm complete miscibility for the system USiO4-ThSiO4. The structure of the end members was studied in detail with XRD and discussed with special regard to the oxygen positions and the often neglected Si-O bond length. USiO4, could be obtained without UO2 impurities and the lattice parameters derived from Rietveld refinement as c = 6.2606(3) angstrom and a = 6.9841(3) angstrom. The Si-O distance in USiO4 appears to be 1.64 angstrom, which is more reasonable than earlier reported values.
引用
收藏
页码:854 / 860
页数:7
相关论文
共 39 条
[11]   Simulation of thermodynamic mixing properties of actinide-containing zircon solid solutions [J].
Ferriss, E. D. A. ;
Ewing, R. C. ;
Becker, U. .
AMERICAN MINERALOGIST, 2010, 95 (2-3) :229-241
[12]   Composition and origin of intermediate solid solutions in the system thorite-xenotime-zircon-coffinite [J].
Forster, H. -J. .
LITHOS, 2006, 88 (1-4) :35-55
[13]  
FRONDEL C, 1957, AM MINERAL, V42, P759
[14]  
FUCHS LH, 1958, AM MINERAL, V43, P243
[15]  
GEORGE G.N., 2000, EXAFSPAK SUITE COMPU
[16]  
Goldschmidt V.M., 1954, Geochemistry
[17]  
Hemingway B. S., 1982, 82619 US GEOL SURV
[18]   SYNTHESIS OF COFFINITE-USIO4 [J].
HOEKSTRA, HR ;
FUCHS, LH .
SCIENCE, 1956, 123 (3186) :105-105
[19]   Local structure of actinide dioxide solid solutions Th1-xUxO2 and Th1-xPuxO2 [J].
Hubert, S. ;
Purans, J. ;
Heisbourg, G. ;
Moisy, P. ;
Dacheux, N. .
INORGANIC CHEMISTRY, 2006, 45 (10) :3887-3894
[20]   DISSOLUTION AND ALTERATION OF URANINITE UNDER REDUCING CONDITIONS [J].
JANECZEK, J ;
EWING, RC .
JOURNAL OF NUCLEAR MATERIALS, 1992, 190 :157-173