Phase equilibria and critical phenomena in the cesium nitrate-water-butyric acid ternary system at 5–100°C

Abstract

The solubility, phase equilibria, and critical phenomena in the cesium nitrate-water-butyric acid ternary system, in which the boundary binary liquid system is not separated over the whole temperature range of its liquid state, were studied by the visual-polythermal method at 5–100°C. The temperature of formation of the critical node of the monotectic state (96.2°C) and the solution compositions corresponding to the critical points of solubility at different temperatures were determined. The distribution coefficients of butyric acid between the aqueous and organic phases of the monotectic state were calculated. The butyric acid salting-out from aqueous solutions with cesium nitrate insignificantly increased with temperature. The constructed phase state isotherms confirmed the fragment of the scheme of the topological transformation of the phase diagrams of the salt-binary solvent ternary systems with salting-in and salting-out.