LAUSR

The stable phase equilibria of the ternary system MgCl2 + SrCl2 + H2O and the two quaternary systems NaCl + MgCl2 + SrCl2 + H2O and KCl + MgCl2 + SrCl2 + H2O at 373 K were investigated using an isothermal method. Based on the experimental results, the isothermal solubility diagram of the ternary system MgCl2 + SrCl2 + H2O, and the solubility diagrams and water content diagrams of the two quaternary systems were constructed. The results show that the ternary system MgCl2 + SrCl2 + H2O at 373 K belongs to the simple co-saturated type without complex salt or solid solution. There are two invariant points, three univariant curves and three crystallization fields corresponding to SrCl2·2H2O, SrCl2·H2O and MgCl2·6H2O. The quaternary system NaCl + MgCl2 + SrCl2 + H2O at 373 K is of the simple co-saturated type and no complex salt or solid solution are found. The phase diagram contains two invariant points, five univariant curves and four crystallization fields (where the solids are NaCl, MgCl2·6H2O, SrCl2·H2O and SrCl2·2H2O). The system KCl + MgCl2 + SrCl2 + H2O at 373 K has a double salt named carnallite (KCl·MgCl2·6H2O) without solid solution formation. The phase diagram contains three invariant points, seven univariant curves and five crystallization fields (where the solids are KCl, MgCl2·6H2O, SrCl2·H2O, SrCl2·2H2O and KCl·MgCl2·6H2O).