LiCl-NaCl-KCl-H2O溶液体系水活度的分子动力学模拟

Molecular Dynamics Simulation of the Water Activity for LiCl-NaCl-KCl-H2O Solution Systems

中文关键词:  水盐混合溶液  水活度  分子动力学

英文关键词:Mixed salt solutions  Water activity  Molecular dynamics

中文摘要:

      盐湖卤水中含有大量的锂、钾资源,研究卤水的水活度的预测模型和方法对于资源的综合利用具有重要的意义。采用分子动力学模拟方法结合Kirkwood-Buff溶液理论研究了 LiCl-NaCl-KCl-H₂O溶液体系及其子体系的离子—水相互作用,计算了水活度。溶液的离子强度范围从1.0 mol·kg-1至6.0 mol·kg-1。模拟计算结果与实验值和Dinane-Pitzer模型计算值的变化趋势相一致。研究并讨论了体系中离子—水相互作用对水活度及相关热力学量的影响。

英文摘要:

      Salt lake brines contain large amount of lithium and potassium resources.Studying the prediction models and methods of water activities for brines shows significance in utilizing these resources.In this work,molecular dynamics combined with Kirkwood-Buff solution theory is employed to study the ion-water interaction and to calculate the water activities for LiCl-NaCl-KCl-H₂O solution systems.The ionic strength of the solutions is varied from 1.0 mol kg-1 to 6.0 mol kg-1.The simulated results show the consistent trend to the experimental data.The effect of ion-water interaction to water activities and related thermodynamic properties are investigated and discussed.