Extraction of Lithium from Salt Lake Brine with Triisobutyl Phosphate in Ionic Liquid and Kerosene  

作　　者：GAO Daolin YU Xiaoping GUO Yafei WANG Shiqiang LIU Mingming DENG Tianlong CHEN Yuwei BELZILE Nelson 

机构地区：[1]Tianfin Key Laboratory of Marine Resources and Chemistry, College of Chemical Engineering and Material Science, Tianfin University of Science and Technology, Tianfin 300457, P. R. China [2]Department of Chemistry & Biochemistry, Laurentian University, Sudbury P3E2C6, Canada

出　　处：《Chemical Research in Chinese Universities》2015年第4期621-626,共6页高等学校化学研究（英文版）

基　　金：Supported by the National Natural Science Foundation of China（Nos.21276194, U1407113）, the Training Program for Changjiang Scholars and Innovative Research Team in University, China（No.[2013]373） and the Innovative Research Team of Tianjin Municipal Education Commission, China（No.TD12-5004）.

摘　　要：Three ionic liquids（ILs）, namely, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-me- thylimidazolium bis[（trifluoromethyl）sulfonyl]imide and 1-ethyl-3-methylimidazolium bis[（trifluoromethyl）sul- fonyl]imide with the triisobutyl phosphate（TIBP） and kerosene system were respectively used to extract lithium ion from salt lake brine with a high concentration ratio of magnesium and lithium experimentally. Results indicate that the highest extraction selectivity for lithium was obtained with IL 1-ethyl-3-methylimidazolium bis[（trifluoromethyl）- sulfonyl]imide. The effects of solution pH and phase ratio R（O/A） on the extractive step and the influence of acid concentration of the stripping solution and R（O/A） on the back extraction step were also investigated systematically. The single-step extraction efficiency of lithium ion was 83.71% under the optimal extraction conditions, and the single-step back extraction efficiency was 85.61% with a 1.0 mol/L HCI in 1.0 mol/L NaCI medium as stripping agent at R（O/A）=2. The liquid-liquid extraction mechanism and the complex of the ligand with lithium were proposed.Three ionic liquids（ILs）, namely, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-me- thylimidazolium bis[（trifluoromethyl）sulfonyl]imide and 1-ethyl-3-methylimidazolium bis[（trifluoromethyl）sul- fonyl]imide with the triisobutyl phosphate（TIBP） and kerosene system were respectively used to extract lithium ion from salt lake brine with a high concentration ratio of magnesium and lithium experimentally. Results indicate that the highest extraction selectivity for lithium was obtained with IL 1-ethyl-3-methylimidazolium bis[（trifluoromethyl）- sulfonyl]imide. The effects of solution pH and phase ratio R（O/A） on the extractive step and the influence of acid concentration of the stripping solution and R（O/A） on the back extraction step were also investigated systematically. The single-step extraction efficiency of lithium ion was 83.71% under the optimal extraction conditions, and the single-step back extraction efficiency was 85.61% with a 1.0 mol/L HCI in 1.0 mol/L NaCI medium as stripping agent at R（O/A）=2. The liquid-liquid extraction mechanism and the complex of the ligand with lithium were proposed.

关 键 词：Ionic liquid Triisobutyl phosphate EXTRACTION LITHIUM Salt lake brine 

分 类 号：TQ265.11[化学工程—有机化工] TF826.3[冶金工程—有色金属冶金]