Investigation of the Ternary Reciprocal System Na,Ba||Br,MoO4

• Published in: Russian journal of inorganic chemistry Vol. 64; no. 8; pp. 1047 - 1053
• Main Authors: Danilushkina, E. G., Garkushin, I. K., Ryzhkova, D. S.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.08.2019; Springer Nature B.V
• Subjects: Barium; Chemistry; Chemistry and Materials Science; Crystallization; Cutting; Differential thermal analysis; Eutectic composition; Eutectic temperature; Inorganic Chemistry; Melting points; Organic chemistry; Partitions; Phase equilibria; Physicochemical Analysis of Inorganic Systems; Sodium bromides; Sodium molybdate; X ray powder diffraction; phase diagram; eutectic; phase equilibria; differential thermal analysis
• ISSN: 0036-0236; 1531-8613
• DOI: 10.1134/S0036023619080035

Theoretical partition of the ternary reciprocal system Na,Ba||Br,MoO 4 into simplexes was performed, the stable diagonal of the system was determined, and the heat of the reaction at the conversion point was calculated. The chemical interaction in the system and the phase equilibria were described, and the crystallization fields of phases were delimited. The validity of the theoretical partition was confirmed by experimental investigation of the stable diagonal and two stable elements of the ternary reciprocal system Na,Ba||Br,MoO 4 by differential thermal analysis. It was found that the system Na,Ba||Br,MoO 4 is a singular irreversible reciprocal system with eutectic melting. The system is divided by the stable cutting diagonal NaBr–BaMoO 4 into two stable phase triangles, NaBr–BaBr 2 –Na 2 MoO 4 and NaBr–BaMoO 4 –Na 2 MoO 4 . The results of the partition were corroborated by the X-ray powder diffraction analysis data. In the stable cutting diagonal, a saddle quasi-binary eutectic point, e 721°C, was revealed. The coordinates (melting point and composition) of two ternary eutectics, E 1 586°C and E 2 525°C, were found. The maximum crystallization field in the composition square corresponds to high-melting barium molybdate.