The phase equilibrium and physicochemical properties（density,conductivity and pH value）of the ternary system NaVO3—Na3PO4—H2O were studied at 298 K by the isothermal dissolution method.According to the determined data,the phase diagram and composition-proerties-composition diagram were plotted.The isothermal solubility diagram of the ternary system consists of two univariant curves,one invariant point B,and two crystallization regions for salt Na3 PO>4·8H2O and NaVO3,respectively.No double salt or solid solution is formed.Physicochemical properties（density,conductivity and pH value）regularly change with the composition of solution.
Zabuye saline lake, Tibet, China, is unrivalled in the world for its high concentration of chloride, sulfate, carbonate and borate of lithium, sodium and potassium. Always at the later stage of the evaporation of brines, most sodium and potassium salts are crystallized out, so the main components of brines can be described with the Li+, Mg2+/Cl-, SO42-, CO32-, B4O72--H2O system. As a part of study on the equilibrium of this complex system, the equilibrium solubilities and phase diagram of the quinary system Li+/Cl-, SO42-, CO32-, B4O72--H2O at 298 K were studied by isothermal dissolution equilibrium method. In the 3-dimentional solubility diagram or its projection diagram saturated with solid LiCl, there are four crystallization fields, four univariant curves and one invariant point. At the invariant point, the saturated solid salts are LiCl·H2O, Li2B4O7·3H2O, Li2CO3 and Li2SO4·H2O. No double salt or solid solution is formed.
