Editors: | F. Kongoli, M. Gaune-Escard, J. Dupont, R. Fehrmann, A. Loidl, D. MacFarlane, R. Richert, M. Watanabe, L. Wondraczek, M. Yoshizawa-Fujita, Y. Yue |
Publisher: | Flogen Star OUTREACH |
Publication Year: | 2019 |
Pages: | 177 pages |
ISBN: | 978-1-989820-00-1 |
ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
Previously, [1] the possible options for the system Li,Na,U||F,Cl polyhedration were considered. The system LiF-NaCl is eutectical [1] (eutectic 0.415 mole LiF at 685°С), so within the reciprocal system Li,Na,U||F,Cl , diagonal LiF-NaCl is stable. It is also known [2, Р. 88] that a NaF-UF4 system is characterized by 3 eutectics (0.215 mole UF4 at 618°С; 0.28 mole UF4 at 623°С and 0.56 mole UF4 at 680°С), 2 peritectics (0.325 mole UF4 at 648°С and 0.37 mole UF4 at 673°С, 2 congruently melting compounds (R1=3NaF-UF4, R2=7NaF-6UF4), and 2 incongruently melting ones (2NaF-UF4, 5NaF-3UF4). As a result, it is possible to consider 3 variants of polyhedration: two with the stable diagonal LiF-UCl3 (LiF-UCl3, NaF-UCl3 and LiF-UCl3, NaCl-UF4), and one with the diagonals LiCl-UF4, NaCl-UF4. In the case of polyhedration with the stable diagonals LiF-UCl3 and 3 diagonals from the apex NaCl, the initial prism of the reciprocal system consists of 5 tetrhedra: LiF-NaF-NaCl-R1, LiF-UF4-NaCl-UCl3, LiF-UF4--NaCl-R2, LiF-LiCl-NaCl-UCl3, and LiF-NaCl-R1-R2. When all stable diagonals are of the eutectic type, then the tetrahedron LiF-LiCl-NaCl-UCl3 is bounded by 5 eutectic binary systems and by LiCl-NaCl. This includes the continuous rows of solid solutions. Systems LiF-NaF-NaCl-R1, LiF-NaF-NaCl-UCl3 , and LiF-NaF-UCl3-R1 are bounded by 6 binary and 4 ternary eutectic systems.
This work has been performed under the program of fundamental research SB RAS (project 0336-2016-0006) and partially supported by the RFBR project 17-08-00875.