中文摘要：

为了开发利用盐湖卤水中的锂、钾资源,采用等温蒸发法研究了三元体系Li^＋、K^＋／／SO4^2--H2O273K时的介稳相平衡，测定了该体系的溶解度和液相密度．根据溶解度数据绘制了相图。该体系的介稳相图由3条单变量曲线、3个结晶相区和2个共饱点组成。3个结晶区分别对应于K2SO4、Li2SO4·H2O和KLiSO4的结晶区；共饱点液相组成分别为w（Li2SO4）26．21％、w（K2SO4）1．82％和w（Li2SO4）12．91％、w（K2SO4）7．94％。同时用经验公式计算了平衡液相的密度．计算结果与实验数据偏差很小。

英文摘要：

In order to developing lithium and potassium resources in the salt lake brine, the metastable equilibrium of Li^＋ ,K^＋//SO4^2- - H2O at 273K was studied by isothermal evaporation method. On the basis of determining the solubility and density of the equilibrium solution, the phase diagram of the system was drawn, which contained three single variable curves, three crystallization phase areas and two co-saturation points. The three crystallization phase areas corresponded to the crystallization phase areas of K2SO4, Li2SO4· 10H2Oand KLiSO4, separately. The composition of equilibriumsolution of the two co-saturation points were： w（Li2SO4） 26.21% , w（K2SO4）1.82 % and w（Li2SO4）12.91% , w （K2SO4）7.94%. At last, the density of equilibrium solution was calculated via empirical formula. The deviation of calculation results and experimental data were very small.