盐湖卤水协同萃取提锂及基础热力学性质  

Co-extraction of Lithium from Salt Lake and Its Thermodynamic Properties

作　　者：李锦丽[1] 朱华芳[1] 王敏[1] 时历杰[1] 赵有璟 张宏韬[1] 葛飞[1] 康为清 高洁[1] 

机构地区：[1]中国科学院青海盐湖研究所盐湖资源化学实验室,西宁810008

出　　处：《无机化学学报》2014年第10期2389-2393,共5页Chinese Journal of Inorganic Chemistry

基　　金：青海省自然科学基金面上项目(No.2011-Z-916);青海省科技支撑项目(No.2013-G-137A)资助项目

摘　　要：为了充分利用盐湖卤水中丰富的锂资源,提出了以磷酸三丁酯(TBP)-乙酸丁酯(BA)-FeCl3-260#磺化煤油体系协同萃取提锂的方法。针对该体系,考察了卤水酸度、nFe/nLi比以及温度对协同萃取过程的影响。根据锂离子及其它主要离子萃取率的变化,确定了最优萃取条件为:pH=2,nFe/nLi=3.0,T=20℃。在最优条件下,单级萃取率达到90%左右。同时,研究了萃取过程的热焓、吉布斯自由能及熵变等基础热力学性质。结果表明,在选定的萃取体系和条件下,锂的萃取反应为放热反应,萃取过程为熵减过程。In order to comprehensively utilize the lithium resource from Salt Lake, a method using the TBP-BAFeCl3-260#brimstone kerosene system to extract lithium was proposed. In view of this synergetic extraction system, several effects including pH, Fe-to-Li ratio and temperature on the extraction process were investigated.According to the extraction rates of lithium ion and other major ions existing in the brine, optimum condition was obtained as pH 2, Fe/Li molar ratio 3.0 and temperature 20 ℃. It was found that under this condition, the singlestage extraction yield of lithium could reach 90%. Additionally, thermodynamic properties like enthalpy, Gibbs free energy and entropy of the extraction process were also calculated in this study. The results indicated that the extraction reaction is exothermic and it is an entropy reduction process.

关 键 词：锂 协同萃取 乙酸丁酯 热力学性质 

分 类 号：TQ420.6[化学工程]