Solid–Liquid Phase Equilibria of the Ternary System (CsCl+Cs₂SO₄+H₂O) at (288.15 and 308.15) K and 0.1 MPa

Abstract

This paper investigates the solid–liquid phase equilibria of ternary system (CsCl+Cs₂SO₄+H₂O) at 288.15 and 308.15 K with isothermal dissolution method. The solubilities and physicochemical properties (refractive index, density and pH value) of the ternary system were determined, and the corresponding phase diagrams and physicochemical property versus compositions at two temperatures were plotted. It was found that there are all one invariant point, two univariant curves, and two crystallization regions corresponding to cesium chloride and cesium sulfate at both temperatures. There are no double salts or solid solution in this system and it belongs to the simple type of salt–water ternary system. The physicochemical properties of the ternary system at the two temperatures showed a regular variation with the changing of cesium chloride concentration in the solution. Moreover, on the basis of empirical equations of density and refractive index, the calculation values of density and refractive index for the ternary system at two temperatures were in consistent with the experimental data.