三元体系NaBr-Na2SO4-H2O 和 NaBr-KBr-H2O 373 K相平衡

摘要

针对川西盆地富硼钾溴地下卤水组成，采用等温溶解平衡法研究了三元体系 NaBr-Na2SO4-H2O 和NaBr-KBr-H2O在373 K时的相平衡，测定了373 K条件下平衡溶液的溶解度和密度，根据实验数据绘制相应的相图和密度图。研究发现：两个三元体系在373 K条件下均属于简单共饱和型，无复盐及固溶体生成。相图中均有一个共饱和点，2个平衡固相结晶区和2条单变量曲线。在三元体系NaBr-Na2SO4-H2O中，平衡固相分别为：NaBr和Na2SO4，三元体系NaBr-KBr-H2O相应的平衡固相分别为：NaBr和KBr。并简单讨论了密度的变化规律。%Phase equilibria of two ternary systems NaBr-Na2SO4-H2O and NaBr-KBr-H2O at 373 K were studied by an isothermal solution saturation method. The solubility and density of these systems were determined experimentally and related phase diagrams were obtained. The results show that the two systems are both of simple type with no complex salts or solid solutions formed. Both of the phase diagrams show that they have one eutectic point, two univariant curves and two regions of crystallization. The solid phase in NaBr-Na2SO4-H2O is cpmposited of sodium bromide(NaBr) and sodium sulfate(Na2SO4), while sodium bromide(NaBr) and potassium bromide(KBr) are the components of the solid phase of NaBr-KBr-H2O. Density change of the two systems was discussed.