Variants of T-x-y-z Diagrams for Subsystems LiF-LiCl-NaCl-UCl3, LiF-NaF-NaCl-UC3, 7NaF-6UF4-LiF-UF4-UCl3, 3NaF-UF4-LiF-NaF-UCl Vasily Lutsyk1; Vera Vorob'eva1; Maria Parfenova2; Marina Lamueva3; 1INSTITUTE OF PHYSICAL MATERIALS SCIENCE SB RAS, Ulan-Ude, Russian Federation; 2TOMSK STATE UNIVERSITY OF CONTROL SYSTEMS AND RADIO-ELECTRONICS, Tomsk, Russian Federation; 3INSTITUTE OF PHYSICAL MATERIALS SCIENCE, Ulan-Ude, Russian Federation; PAPER: 125/Molten/Regular (Oral) SCHEDULED: 16:20/Fri. 25 Oct. 2019/Ambrosia A (77/RF) ABSTRACT: 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-UF<sub>4</sub>, R2=7NaF-6UF<sub>4</sub>), and 2 incongruently melting ones (2NaF-UF<sub>4</sub>, 5NaF-3UF<sub>4</sub>). As a result, it is possible to consider 3 variants of polyhedration: two with the stable diagonal LiF-UCl<sub>3</sub> (LiF-UCl<sub>3</sub>, NaF-UCl<sub>3</sub> and LiF-UCl<sub>3</sub>, NaCl-UF4), and one with the diagonals LiCl-UF<sub>4</sub>, NaCl-UF<sub>4</sub>. In the case of polyhedration with the stable diagonals LiF-UCl<sub>3</sub> and 3 diagonals from the apex NaCl, the initial prism of the reciprocal system consists of 5 tetrhedra: LiF-NaF-NaCl-R<sub>1</sub>, LiF-UF<sub>4</sub>-NaCl-UCl<sub>3</sub>, LiF-UF<sub>4</sub>--NaCl-R<sub>2</sub>, LiF-LiCl-NaCl-UCl<sub>3</sub>, and LiF-NaCl-R<sub>1</sub>-R<sub>2</sub>. When all stable diagonals are of the eutectic type, then the tetrahedron LiF-LiCl-NaCl-UCl<sub>3</sub> is bounded by 5 eutectic binary systems and by LiCl-NaCl. This includes the continuous rows of solid solutions. Systems LiF-NaF-NaCl-R<sub>1</sub>, LiF-NaF-NaCl-UCl<sub>3</sub> , and LiF-NaF-UCl<sub>3</sub>-R<sub>1</sub> 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. References: 1. V. Lutsyk, V. Vorob'еva, M. Parfenova, M. Lamueva. Materials for the Nuclear Reactors of Generation IV: Polyhedration of the Chloride-Fluoride Reciprocal Systems // Sustainable Industrial Processing Summit & Exhibition SIPS-2018. Intl. Symp. on Sustainable Molten Salt and Ionic Liquid Processing. - Id Paper: 96 https://www.flogen.org/sips2018/technical_program.php?a=c51ce410c124a10e0db5e4b97fc2af3 2. Gabcova J., Peschl J., Malinovsky M. et al // Chemicke Zvesti (Chemical Papers). 1976. V. 30. No 6. P. 796-804. 3. Thoma R.E., Editor. Phase Diagrams of Nuclear Reactor Materials, Union Carbide Corp., Oak Ridge, Tennessee, 1959, 205 pp. |