拉果错盐湖卤水蒸发过程中Li+富集行为的分子动力学模拟

Molecular Dynamics Simulation of Li+ Enrichment Behavior during Brine Evaporation in Laguocuo Salt Lake

中文关键词:  盐湖卤水  分子动力学模拟  离子对  配位数  扩散系数

英文关键词:Salt lake brine  Molecular dynamics simulation  Ion pair  Coordination number  Diffusion coefficient

中文摘要:

      采用分子动力学模拟,研究了西藏拉果错盐湖卤水中阴、阳离子以及水分子间的相互作用行为。以盐湖卤水等温蒸发过程中粒子浓度变化的四个阶段为研究对象,分别计算了不同体系的扩散系数、配位数、均方位移和径向分布函数。计算结果表明,液相浓度越低时,H₂O分子对各离子之间的相互作用有抑制作用,液相中离子浓度越高时,SO₄2-易与CO₃2-竞争Li⁺形成离子对,从而影响盐湖卤水中Li⁺的富集。本文研究结果对盐湖卤水中Li⁺的迁移行为作出了机理解释,为盐湖卤水提锂的发展奠定了理论基础。

英文摘要:

      Molecular dynamics simulation was used to study the interaction between anions,cations and water molecules in the brine of Laguocuo salt lake in Tibet. Taking the four stages of particle concentration changes during the isothermal evaporation of salt lake brine as the research objects,the diffusion coefficient,coordination number,mean square displacement and radial distribution function of different systems were calculated respectively. The calculation results show that when the liquid concentration was lower,the H₂O molecule had an inhibitory effect on the interaction between the ions,when the ion concentration in the liquid phase was higher,SO₄2- competed easily with CO₃2- for Li⁺ to form an ion pair,thus affecting the enrichment of Li⁺ in salt lake brine. The results of this paper provide a mechanism explanation for the migration behavior of Li⁺ in salt lake brine,it has laid a theoretical foundation for the development of lithium extraction from salt lake brine.