应用化学 ›› 1994, Vol. 0 ›› Issue (1): 7-11.

• 研究论文 • 上一篇    下一篇

四元交互体系Li+,K+/Cl,SO42--H2O 50,75℃相平衡研究

任开武, 宋彭生   

  1. 中国科学院盐湖研究所 西宁 810008
  • 收稿日期:1992-12-25 修回日期:1993-09-07 出版日期:1994-02-10 发布日期:1994-02-10
  • 基金资助:
    国家自然科学基金资助课题

A Study on Equilibrium Solubilities in the Quaternary Reciprocal System of Li+, K+/Cr-,at 50℃ and 75℃

Ren Kaiwu, Song Pengsheng   

  1. Qinghai Inistitute of Salt Lakes, Chinese Academy of Sciences, Xining 810008
  • Received:1992-12-25 Revised:1993-09-07 Published:1994-02-10 Online:1994-02-10

摘要: 采用等温溶解平衡法测定了四元交互体系Li+,K+/Cl,SO42--H2O 50,75℃的溶解度和平衡溶液的物化性质(密度、粘度、折光率).该四元交互体系50,75℃的溶解度等温图有5个相区:即Li2SO4·H2O,KLiSO4,KCl,K2SO4,LiCl·H2O,7条单变量曲线,3个共饱点,其中Li2SO4·H4O+KCl+LiCl·H4O为一致零变量点。用我们以往提出的经验公式处理了平衡溶液的密度和折光率,由所测得的溶解度数据,求得了高温和高锂浓度下的电解质溶液Pitzer模型的离子相互作用参数。计算了各平衡溶液中盐的活度和水的活度。还计算了该四元交互体系25℃的溶解度,考察了Pitzer电解质溶液理论在水-盐溶解度计算中的应用。

关键词: 含锂钾水盐体系, 平衡溶解度, 相图, Pitzer模型

Abstract: The eqtiibrium solubilities of title quaternary system were studied at 50,75℃ by the isothernlal method. The phase diagrams of the system consist of seven solubility branches and have five crvstallization fields : KLiSO4, Li2SO4·H2O, KCl,K2SO4, and LiCl·H2O. The first one is the largest. Three invariant points exist in the system : LiCl·H2O +KCl +Li2SO4·H2O,KCl+K2SO4+KLiSO4,andKCl+KLiSO4+Li2SO4·H2O. The first one is a congrLient eutonic point, and the others are incongruent. The ion interaction pararneters of the Pitzer model for rnixed electrolyte solution at 50℃ and 75℃ were obtained by fitting the determined solubility data. The water activity of the equilibrium liquid, and the solubility product of saIts were calculated. The empirical eqtiations of density and refractive index of the solution in relationto to its composition were used to correlate the data. The results are in good agreement.

Key words: lithitim salt, potassium salt, chloride, sulphate, equilibrium solubility, phase dia-gram, Pitzer model