Solid and Liquid Phase Equilibria of Li+, K+, Ca2+∥Cl––H2O Quaternary Systems at 298.15 and 273.15 K

Brine deposited in Chaerhan salt lake belongs to the chloride type and can be simplified into the hexnary system Li+, Na+, K+, Mg2+, Ca2+, Cl––H2O. The known solubility data indicate that significant salting-in effects exist in its subsystems of KCl–LiCl–H2O and KCl–CaCl2–H2O, which inevitably affect the properties and solubility behavior of actual brine. In this work, the solubility behavior study and phase diagram determination are extended to the quaternary system of Li+, K+, and Ca2+∥Cl––H2O. The phase equilibrium data at 298.15 and 273.15 K are reported, and five solid species, including two double salts KCl·CaCl2 and LiCl·CaCl2·5H2O, are found. The salting-in effect is still exhibited in the Li+, K+, and Ca2+∥Cl––H2O system and results in a very high total salt content at invariant points; e.g., they are 59.08 and 46.93% at 298.15 and 273.15 K, respectively.