Water Activity and Phase Equilibria Measurements and Model Simulation for the KCl-SrCl2-H2O System at 323.15 K.

Water activities for the ternary system of KCl-SrCl2-H2O and its sub-binary system SrCl2-H2O were elaborately measured using an isopiestic method at 323.15 K. The solubility isotherms for the KCl-SrCl2-H2O system were determined by the isothermal equilibrium method. It is found that the measured isopiestic composition lines for the KCl-SrCl2-H2O system deviated from the Zdanovskii rule, especially at a lower water activity. The Pitzer-Simonson-Clegg model was used to correlate the measured water activity and solubility data, simulate the thermodynamic properties, and predict the solubility of the ternary system. The reliability of the solubility data measured in this work was evaluated by comparing with the solubility isotherms calculated with the Pitzer-Simonson-Clegg model. The measured water activity and solubility results are of great importance for predicting the phase diagram of other multicomponent systems that related to this ternary system. [ABSTRACT FROM AUTHOR]