Phase equilibria in quinary system NaBr-KBr-MgBr2-CaBr2-H2O at 298 K and 323 K

According to the multi-component system Na-K-Ca-Mg-Sr-Li-Cl-B4O7-Br-SO4-I-H2O of underground brine in Sichuan basin, the phase equilibrium relationships of quinary systems NaBr-KBr-MgBr2-CaBr2-H2O at 298 and 323 K were studied by isothermal solution equilibrium method, the solubilities of the equilibria solution of the quinary system were determined under the corresponding temperatures, and the corresponding phase diagrams were plotted according to the phase equilibrium experiment data (saturated with KBr). The results of research show that the quinary system has complex salt at 298 K and 323 K. There is complex salt KBr•MgBr2•6H2O formation at 298 K and the phase diagram contains two co-saturated points, five dissolution isotherms and four solid crystallization regions (corresponding to KBr•MgBr2•6H2O, NaBr•2H2O, NaBr and CaBr2•6H2O, respectively). There are two kinds of complex salts KBr•MgBr2•6H2O and 2MgBr2•CaBr2•12H2O formation at 323 K and the phase diagram contains three co-saturated points, seven dissolution isotherms and five solid crystallization regions (corresponding to KBr•MgBr2•6H2O, NaBr•2H2O, NaBr, CaBr2•4H2O and 2MgBr2•CaBr2•12H2O, respectively). © All Right Reserved.