Vol 23, No 4 (2023)

The division of the four-component reciprocal system Na+, Rb+, Cs+ || F−, NO3− into stable elements was carried out for the first time. The phase tree, confirmed by the experimental data from the differential thermal analysis, was constructed. The chemical interaction in a yet unexplored faceting element, i. e. in the three-component reciprocal system Na+, Cs+ || F−, NO3−, and in the four-component reciprocal system was studied. Phase equilibria in the three-component reciprocal system Na+, Cs+ || F−, NO3− and in the stable tetrahedron NaF-NaNO3-RbNO3-CsNO3 of the four-component reciprocal system Na+, Rb+, Cs+ || F−, NO3– were experimentally studied. The calculation-graphical method to predict the melting temperature in the stable elements of the four-component reciprocal system Na+, Rb+, Cs+ || F−, NO3− by describing the lower and the upper boundaries of properties according to the data of the one-, two- and three-component systems was used. The obtained compositions of eutectic alloys can be used as low-melting electrolytes for chemical cells, heat-storing materials, heat-storage mediums, melt-solvents of inorganic substances and as a reference material.

The temperature dependencies of physical and chemical properties (viscosity, density, electrical conductivity) and the melting temperature of 1M solutions of lithium salts (LiClO4 and LiBF4) in the mixture of sulfolane and sulfurous anhydride (∼1M) were studied. It was shown that the introduction of 1M (5% wt.) of sulfurous anhydride into 1M solutions of LiClO4 and LiBF4 in sulfolane increased the specific and corrected electrical conductivity, densities, activation energy of electrical conductivity and viscous flow of electrolyte solutions; and reduced viscosity and melting temperatures.