Li^+,Na^+//SO_4^(2-),B_4O_7^(2-)-H_2O交互四元体系288K介稳相平衡研究  

Study on Metastable Equilibria in Quaternary System Li^+, Na^+//SO_4^(2-), B_4O_7^(2-)-H_2O at 288 K

作　　者：桑世华[1] 虞海燕[1] 蔡冬珠[1] 

机构地区：[1]成都理工大学材料与生物工程学院,成都610059

出　　处：《无机化学学报》2005年第9期1316-1320,1274,共5页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金资助项目(No.40303010)

摘　　要：采用等温蒸发法研究了四元体系Li+,Na+//SO42-,B4O72--H2O288K介稳相平衡及平衡液相物化性质(密度、电导率、折光率、粘度和pH值),测定了该四元体系288K条件下介稳平衡溶液溶解度及物化性质。根据实验数据绘制了相应的介稳相图及物化性质组成图。研究发现:该体系介稳平衡中有复盐Li2SO·4Na2SO4形成。其介稳相图中有3个共饱和点,7条单变量曲线,平衡固相为:Li2SO·4H2O,Na2SO4,Li2SO·4Na2SO4,Li2B4O7·3H2O,Na2B4O·710H2O。复盐Li2SO·4Na2SO4和一水硫酸锂(Li2SO·4H2O)有较小的结晶区,而Li2B4O7·3H2O和Na2B4O7·10H2O有较大的结晶区;该四元体系介稳平衡条件下未发现Na2SO·410H2O的结晶区。An experimental study on metastable equilibria at 288 K in the quaternary system Li^＋, Na^＋//SO4^2-, B4O7^2--H2O was done by isothermal evaporation method. Metastable equilibrium solubilities and physico-chemical properties such as density, conductivity, pH, refractive index and viscosity of the solution were determined. The results show that the double salt Na2SO4·Li2SO4 forms in the quaternary system Li^＋, Na^＋//SO4^2-, B4O7^2--H2O at 288 K. According to the experimental data, the metastable equilibrium phase diagram and the physico-chemical composition diagram were plotted. In the metastable phase diagram, the quaternary system has three invarlant points, seven univariant curves, five fields of crystallization （Li2SO4·H2O, Na2SO4, Li2B4O7·3H2O, Na2B4O7· 10H2O, Na2SO4·Li2SO4）. The double salt （Na2SO4·Li2SO4） and Li2SO4·H2O have smaller crystallization fields, but borates （Li2B4O7·3H2O and Na2B4O7·10H2O） have larger crystallization fields. The crystallization field of Na2SO4·10H2O was not found in the metastable equilibria.

关 键 词：介稳相平衡 硼酸盐 硫酸盐 溶解度 

分 类 号：O614.11[理学—无机化学] TQ131.1[理学—化学]