Li^+,Na^+//CO_3^(2-),B_4O_7^(2-)-H_2O交互四元体系273 K介稳相平衡研究

Metastable Equilibria in the Quaternary System Li^+,Na^+//CO_3^(2-),B_4O_7^(2-)-H_2O at 273 K

我国青藏高原由于特殊的地理气候特点而盐湖众多,西藏境内的扎布耶盐湖卤水中锂、硼、钾浓度之高,在世界盐湖中也非常罕见。该盐湖属碱性盐湖,其主要成份为Li^＋、K^＋、Na^＋、Rb^＋、Cs^＋、B4O7^2-、CO3^2-、Cl^-、SO4^2-、H2O等。

Metastable equilibria at 273 K in the quaternary system Li^＋,Na^＋//CO3^2-,B4O7^2--H2O was studied by isothermal evaporation method.Metastable equilibrium solubilities and densities of the solution were determined experimentally.According to the experimental data,the metastable equilibrium phase diagram was plotted.In the metastable phase diagram,the quaternary system has two invariant points E and F,five univariant curves E1E,E2E,E3F,E4F and EF,four fields of crystallization： Na2B4O7·10H2O,Na2CO3·10H2O,Li2B2O4·16H2O and Li2CO3.Boxe（Na2B4O7·10H2O） has the biggest crystallization field,and Na2CO3·10H2O has the smallest crystallization field in the quaternary system.