柴达木盆地富锂钾铷硼卤水多温介稳相平衡与热力学模型研究

柴达木盆地盐湖资源储量大，卤水中富含锂钾铷硼，极具开发价值。盐田工艺由于缺少该卤水体系介稳相图的指导，分卤点偏离、成卤率低、资源综合利用不到30%，导致该宝贵卤水资源的严重浪费。因此，开展具有该卤水组成特征的含锂钾铷硼体系多温介稳相平衡与热力学模型研究对于指导盐湖卤水资源开发利用至关重要。创新硼酸盐溶液研究方法和手段，拟采用先进的微量热技术，精确测定硼酸盐体系的热容、混合热和稀释热等热力学性质，引入溶液中硼的不同形态，拟合获取迄今极为缺乏的硼酸盐体系模型参数及其温度关联式，改进和发展Pitzer电解质溶液理论表达，构建该卤水体系介稳相平衡理论预测的热力学模型，丰富盐卤硼酸盐化学理论，揭示卤水蒸发、盐类结晶沉积、溶解转化的过程与机制，对于推动该类型宝贵盐湖资源锂钾铷硼产品开发及其综合利用具有重要理论意义和实际应用价值。

Salt lake brines in Qaidam Basin with abundance mineral resources are famous for their high concentration of lithium, potassium, rubidium and boron. Due to lack of guidance of the metastable phase diagrams of multicomponent brine systems, the points of brine separation have obvious deviation, the low rate of bittern, and the comprehensive utilization of brine is less than thirty percent, which led to the serious waste of this precious brine resources. Therefore, it is essential to establish the metastable phase equilibria and thermodynamic model at multi-temperature of the brine systems containing lithium, potassium, rubidium and boron to promote the development and utilization of this brine resources. In this project, the innovative research using the advanced micro-calorimetric technique will be adopted to determine the thermodynamic properties of heat capacity, mixing heat and diluting heat for a series of the aqueous borate systems, and the model parameters and the temperature-correlation equations will be obtained through to introduce the species borate existed in solution. And then, a dynamic predictive thermodynamic model of metastable phase equilibria for this salt lake brine resources will be formed based on Pitzer model and to rich the borate chemistry theory, reveal the evaporation path, the process and mechanics of the crystallizing-depositing and dissolving-inverting of minerals. The research have great theoretical significance and application value to promote the development of lithium, potassium, rubidium and boron products and to guide the comprehensive utilization of this precious salt lake brine resources.