三元体系CsCl+MgCl_2+H_2O 298 K介稳相平衡研究  

Metastable phase equilibrium in aqueous ternary system CsCl+MgCl_2+H_2O at 298 K

作　　者：邬莉婷 程兴龙[1] 曾英[1,2] 于旭东[1,2] WU Li-ting;CHENG Xing-long;ZENG Ying;YU Xu-dong(College of Materials and Chemical ＆ Chemical Engineering;Mineral Resources Chemistry Key Laboratory of Sichuan Higher Education Institutions,Chengdu University of Technology,Chengdu 610059,Sichuan Province,China)

机构地区：[1]成都理工大学材料与化学化工学院,四川成都610059 [2]成都理工大学矿产资源化学四川省高校重点实验室,四川成都610059

出　　处：《化学工程》2018年第6期42-46,共5页Chemical Engineering(China)

基　　金：国家自然科学基金资助项目(U1607121;41473059);四川省青年科技创新研究团队资助计划项目(2013TD0005);成都理工大学创新团队项目(KYTD201405)

摘　　要：采用等温蒸发法研究三元体系CsCl+MgCl_2+H_2O 298 K的介稳相平衡。结果发现,相图包含2个共饱点,3条溶解度曲线和3个结晶相区。3个结晶区分别为单盐CsCl,MgCl_2·6H_2O和复盐CsCl·MgCl_2·6H_2O的结晶区。此体系有复盐铯光卤石形成,为复杂三元体系。由相图可知,铯光卤石CsCl·MgCl_2·6H_2O的复盐射线(CW)通过其溶解度曲线(E1E2),属同成分复盐。随着复盐的形成,相图中出现2个共饱点,在共饱点处,均有2种盐和一种平衡溶液达到共饱和。2个共饱点对应的饱和盐分别为MgCl_2·6H_2O+CsCl·MgCl_2·6H_2O和CsCl+CsCl·MgCl_2·6H_2O,且2个共饱点均位于其相应组分点构成的三角形之内,均属于相称共饱点。3种盐结晶区大小按以下顺序排列:CsCl·MgCl_2·6H_2O>CsCl>MgCl_2·6H_2O,其中CsCl·MgCl_2·6H_2O结晶区最大,意味着复盐CsCl·MgCl_2·6H_2O比其他盐更容易析出。The metastable phase equilibrium of the ternary system CsCl＋MgCl2＋H2O at 298 K was studied by isothermal evaporation method. Results show that the phase diagram consists of two invariant points, three univariant curves,and three crystalline regions corresponding to two single salts CsCl,MgCl2·6 H2O and a double salt CsCl· MgCl2·6 H2O. The ternary system belongs to a complex type,with a double salt cesium carnallite（CsCl·MgCl2·6 H2O） formed. From the phase diagram we can see,double salt cesium carnallite,whose double salt ray（CW） through its own solubility curve（E1 E2） in the phase diagram,belongs to congruent double salt. The two invariant points（E1 and E2） are saturated by two salts and an equilibrated solution,and the cosaturated salts for two invariant points are MgCl2·6 H2O ＋ CsCl · MgCl2· 6 H2O and CsCl ＋ CsCl · MgCl2· 6 H2O,respectively. The invariant points E1 and E2 are located in the triangle which constructed by its component points and both belong to the commensurate invariant points. The salt crystal regions are in the following order： CsCl·MgCl2·6 H2O 〉 CsCl 〉 MgCl2·6 H2O. The crystallization zone of double salt CsCl · MgCl2·6 H2O is the largest,which means that the double salt CsCl·MgCl2·6 H2O is easy to be separated from solution.

关 键 词：介稳相平衡 铯盐 光卤石 298 K 

分 类 号：O642[理学—物理化学]