Solid–Liquid Phase Equilibria in the Ternary System CaBr2–SrBr2–H2O at 273, 298, and 323 K

In this paper, the stable phase equilibrium data of the ternary system CaBr2-SrBr2-H2O at T = 273, 298, and 323 K and 101.3 kPa have been determined by isothermal the dissolution equilibrium method. The phase diagrams of them at the investigated temperatures have been drawn. It is found that the isothermal phase diagrams of the CaBr2–SrBr2–H2O system at T = 273, 298, and 323 K are classified as a simple co-saturation type consisting of an invariant point and two univariant curves. The equilibrium solid phases corresponding to an invariant point of the system were detected as CaBr2·6H2O + SrBr2·6H2O at 273 and 298 K and those identified as CaBr2·4H2O + SrBr2·6H2O at 323 K. In this system, calcium bromide exhibits a strong salting-out effect on strontium bromide. Furthermore, isothermal solubilities at three temperatures were compared and discussed.