Phase Equilibria in the Na+,K+//Cl–,NO\(_{3}^{ - }\)–H2O System near Boiling Temperatures. I. Modeling of Ternary Systems

Partial reoptimization of the parameters of the Wang–Gruszkiewicz model has been performed, which made it possible to describe phase equilibria in boundary ternary systems that form a Na⁺,K⁺//Cl^–,NO\(_{3}^{ - }\)–H₂O reciprocal system near the boiling temperatures. The regions of stability of the liquid phase, i.e., the compositions of solutions whose boiling does not lead to isolation of a solid phase were determined. At definite ratios of the amounts of sodium and potassium nitrates in the NaNO₃–KNO₃–H₂O system, the vapor pressure of water over the saturated solutions equals the atmospheric pressure at two different temperatures.