Phase diagram of the reciprocal system K+, Mg2 +//Cl−, NO3−–H2O

Abstract

Solid–liquid phase equilibria of the reciprocal system K+, Mg2+//Cl−, NO3−–H2O were studied in the temperature range 5°C–115°C. Phase diagrams obtained at the temperatures of 5°C, 20°C, 40°C and 60°C are presented. Data for higher temperatures are presented in a table. A semi-empirical model for the description of solid–liquid equilibrium for KNO3–MgCl2 diagonal of this system was developed. The model allows calculating the material balance of crystallization of KNO3, KCl, and KCl·MgCl2·6H2O, respectively, with precision better than 1%. Experimental and calculated data on the solid–liquid equilibrium are compared up to the temperature of 115°C.