戈海文,邓天龙,姚燕

• 1:中国科学院青海盐湖研究所
• 2:天津市海洋资源与化学重点实验室(天津科技大学)

摘要(Abstract)：

采用等温溶解法对章氏硼镁石(MgB_4O_7-9H_2O)在纯水中溶解及转化进行研究,结果表明章氏硼镁石在308.15K下稳定存在12 h,溶解度为0.04813 mol×kg~(-1);12 h后,平衡固相向多水硼镁石(Mg_2B_6O_(11)·15H_2O)转化。根据文献的化学平衡常数以及实验pH值,计算液相中硼酸根离子摩尔分数在溶解转化过程中变化规律,并给出溶液中可能存在的反应及其相应的机理。采用等压法研究了308.15 K下MgB4O_7-H_2O体系离子强度为0.1066~0.2680 mol×kg~(-1)的等压平衡浓度和水活度,计算了渗透系数及饱和蒸汽压,获得了该体系渗透系数和饱和蒸汽压随离子强度的变化规律;应用Pitzer离子相互作用模型,对实验数据进行多元线性回归,得到308.15 K下MgB_4O_7-H_2O体系的纯盐参数β(0)、β(1)、β(2)和Cφ分别为39.3990、-61.5421、655.1369、-86.0430,标准偏差为0.00723。Pitzer离子相互作用模型计算的渗透系数值与实验结果一致,这对完善含镁、硼盐湖卤水体系的热力学模型具有重要意义。

关键词(KeyWords)： MgB4O7-H2O体系;相转变;等压法;渗透系数;Pitzer模型

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(41503061,20836009);; 天津市海洋资源与化学重点实验室(天津科技大学)开放基金(201406)

作者(Author): 戈海文,邓天龙,姚燕

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