三元体系Mg^(2+)/Cl^-,Borate—H_2O25℃相关系和溶液性质的研究

Study on Phase Diagram of Mg^(2+) /Cl^-, Borate-H_2O Ternary System at 25℃

用等温溶解法测定了Mg2+／Cl-，Borate-H2O三元体系25℃时的溶解度．此三元体系等温溶解度图为简单共饱型，它的平衡固相分别为三方硼镁石（Mg2B12O20·15H2O）和MgCl2·6H2O，未产生新的复盐或固溶体。拟合了MgB6O10随MgCl2浓度变化的溶解度曲线方程，并且对平稳溶液的物化性质（密度、粘度、折光率、电导、pH值）进行了测定，用半经验公式描述了一些物化性质随浓度的变化规律，结果令人满意。

The solubilities of Mg2+/Cl-,Borate-H2O ternary system at 25℃ has been determined by the isothermal method. This system is of a simple eutonic type. Its phase diagram consists of two solubility branches and two crystallization fields corresponding to Mg2B12O20,. 15H2O and MgCl2. 6H2O. The solubility line of MgB6O10 is exgressed in terms of the molality of MgCl2.Furthermore, some physico- chemical properties of solutions such as density, refractive index,viscosity, conductivity, and pH were determined. Two equations were used to correlate density and refractive index with composition. Differences between measured and calculated values are less than 0. 10% for density. 0. 15 % for the later.