盐湖卤水提取铷的过程中取代酚类萃取剂的结构修饰

Rubidium and its compounds are widely used in biomedical research, electronics, specialty glass, and pyrotechnics for their excellent optical and electrical properties, and have become a hot point in the research field of new energy materials. Recent research indicated that there are abundant rubidium resources in the salt lakes of western China. This resource is difficult to be efficiently extracted and separated in comprehensive utilization because of its low concentration. Using substituted phenols as extractants is an effective approach to solve this problem. However, the application of this technology is restricted by the selectivity for Rb+. On the basis of our previous work, the structure of the 4-s-butyl-2(-methylbenzyl) phenol (s-BAMBP) and the 4-t-butyl-2(-methylbenzyl) phenol (t-BAMBP) will be modified to get more effective extracting reagents for rubidium in this project. The influence of the structure of prepared substituted phenols upon the selectivity of Rb+ is also investigated. The detail of research contents are summarized below: first of all, synthesize several novel kinds of substituted phenols, and investigate the behavior and disciplinarian of the prepared substituted phenols for Rb+. Secondly, synthesize coordination polymers of MI (M=K, Rb, Cs) based on s-BAMBP, t-BAMBP or their derivatives, and investigate the stability of the crystalline compounds by X-ray crystal structure analysis. Also, the mechanism of extractive reaction is studied and the thermodynamic functions are measured and discussed. At last, discuss the intrinsic relationships between the structures and the thermodynamic functions of the crystalline compounds and the selectivity for Rb+ of substituted phenols, which guide us to prepare more effective Rb+ extractant. As a result, important information and data for rubidium separation by substituted phenol extractants from salt lake will be accumulated. The implementation of the project is undoubtedly helpful to extend the applicability of extraction technique in the hydrometallurgy field, to develop a better understanding of the intrinsic contact of the chemical structure with the extracting properties of substituted phenols, and to improve the comprehensive utilization of salt lakes.

铷及其化合物具有优异的光电等性能，是重要的先进能源材料。我国西部盐湖卤水中蕴藏丰富的铷资源，铷的高效分离提取是盐湖资源综合开发利用的难题。取代酚萃取法是解决该问题的有效途径，但已有的取代酚试剂对铷离子选择性不足是影响该技术应用的主要瓶颈。本项目以盐湖卤水中的铷资源为研究对象，拟探讨取代酚分子的结构修饰及其如何影响铷离子的选择性。具体内容包括：向取代酚类萃取剂分子中引入不同官能基团进行结构修饰，探索其分子结构对铷萃取性能影响的规律；分别通过热力学和萃合物单晶结构稳定性的角度，阐释分离过程中的选择性差别的机理，建立萃取剂分子结构与萃取选择性之间的内在联系。项目对深入认识萃取剂分子结构与萃取性能之间的关系、推进取代酚类萃取剂提取盐湖中铷资源的研究、扩展溶剂萃取技术在湿法冶金中的应用和提高卤水综合利用水平等都有一定意义。

铷及其化合物具有优异的光电等性能，是重要的先进能源材料。我国西部盐湖卤水中蕴藏丰富的铷资源，铷的高效分离提取是盐湖资源综合开发利用的难题。取代酚萃取法是解决该问题的有效途径。本项目以盐湖卤水中的铷资源为研究对象，对常用的t-BAMBP进行结构修饰，合成了7种苄基取代酚变种，考察了萃取剂和稀释剂对钾、铷、铯离子萃取性能影响的规律；以t-BAMBP萃取铷为例，采用改进的斜率法研究了萃取反应的热力学性质；合成了t-BAMBP与Rb和Cs离子形成的萃合物晶体，并通过单晶结构解析获得了萃合物单晶结构信息，进而借助密度泛函理论（DFT）预测了不同金属离子-萃取剂配合团簇能量和光谱性质，同时结合萃取热力学、萃合物晶体结构、有机相光谱分析和DFT萃取物团簇结构能量与光谱计算，认识到取代酚分子的二聚体结构在萃取过程中的重要作用，阐明了分离过程中选择性差异的根源，初步描绘了萃取剂分子结构与萃取能力和选择性之间的内在联系，完成了本项目的预期目标。项目对深入认识萃取剂分子结构与萃取性能之间的关系、推进取代酚类萃取剂提取盐湖中铷资源的研究、扩展溶剂萃取技术在湿法冶金中的应用和提高卤水综合利用水平等都有一定意义。