The isothermal dissolution equilibrium method has been used to investigate the solid and liquid equilibria of quatemary system Li2SO4-Na2SO4-K2SO4-H2O at 288 K. The phase diagram and water diagram were plotted accordi...The isothermal dissolution equilibrium method has been used to investigate the solid and liquid equilibria of quatemary system Li2SO4-Na2SO4-K2SO4-H2O at 288 K. The phase diagram and water diagram were plotted according to the experiment results. It was found that LizSO4-Na2SO4-K2SO4-H2O quaternary system contains four double salts at 288 K. There are six invariant points, twelve univariant curves and seven areas of crystallization： Li2SO4·H2O, Na2SO4·10H2O, K2SO4,LiESO4·3Na2SO4-12H2O, Li2SO4K2SO4, Na2SO4·3K2SO4, 2Li2SO4·Na2SO4- K2SO4. Using the equilibrium solubility data of the quaternary system at 288 K, the solubility product（lnKsp） of solid phase 2LiESO4-Na2SO4.KESO4, which is not reported was acquired. Based on the chemical model of Pitzer＇s electrolyte solution theory, the solubilities for the quaternary system Li2SO4-Na2SO4-K2SO4-H2O at 288 K were calculated with corresponding parameters. Compared the results of experimental measurement with those of calculation, it was shown that the calculated values had a good agreement with the experimental ones.展开更多
基金Supported by the National Natural Science Foundation of China（Nos.U1407108, 41373062） and the Scientific Research and Innovation Team in Universities of Sichuan Provincial Department of Education, China（No. 15TD0009）.
文摘The isothermal dissolution equilibrium method has been used to investigate the solid and liquid equilibria of quatemary system Li2SO4-Na2SO4-K2SO4-H2O at 288 K. The phase diagram and water diagram were plotted according to the experiment results. It was found that LizSO4-Na2SO4-K2SO4-H2O quaternary system contains four double salts at 288 K. There are six invariant points, twelve univariant curves and seven areas of crystallization： Li2SO4·H2O, Na2SO4·10H2O, K2SO4,LiESO4·3Na2SO4-12H2O, Li2SO4K2SO4, Na2SO4·3K2SO4, 2Li2SO4·Na2SO4- K2SO4. Using the equilibrium solubility data of the quaternary system at 288 K, the solubility product（lnKsp） of solid phase 2LiESO4-Na2SO4.KESO4, which is not reported was acquired. Based on the chemical model of Pitzer＇s electrolyte solution theory, the solubilities for the quaternary system Li2SO4-Na2SO4-K2SO4-H2O at 288 K were calculated with corresponding parameters. Compared the results of experimental measurement with those of calculation, it was shown that the calculated values had a good agreement with the experimental ones.
