Solubility in K+-Na+-Mg (4) (2-) aqueous solution at T=298.15 K

Abstract

In the salt solubility predictions for K+-Na+-Mg (4) (2-) aqueous solution the treatment of thermodynamic data of three-component systems at T = 298.15 K involved the application of the Extended Pitzer's ion-interaction model for the pure and mixed electrolyte solutions and criteria of phase equilibrium. Osmotic coefficients data of three-component systems were revised according to recently published parameters of the solutions NaCl(aq) and KCl(aq) that served as reference standards in isopiestic measurements. Parameters of the extended ion-interaction model of K2SO4(aq) are determined by treatment of experimental and predicted values of osmotic coefficient in supersaturated region obtained by the Zdanovskii-Stokes-Robinson rule. Results of salt solubility prediction were compared to experimental solubility data from literature. The agreement between calculated and experimental solubility data in the systems K2SO4 + MgSO4 + H2O, Na2SO4 + MgSO4 + H2O, and Na2SO4 + K2SO4 + H2O at T = 298.15 K, was excellent.