Efficient Extraction of Lithium Ions from High Mg/Li Ratio Brine through the Synergy of TBP and Hydroxyl Functional Ionic Liquids
Efficient Extraction of Lithium Ions from High Mg/Li Ratio Brine through the Synergy of TBP and Hydroxyl Functional Ionic Liquids
复制标题
通过 TBP 和羟基功能离子液体的协同作用，从高镁/锂比盐水中高效萃取锂离子
DOI：
10.1002/cjoc.202000210
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发表时间：
2020-11-17
影响因子：
5.4
通讯作者：
Zhang, Yanqiang
中科院分区：
文献类型：
--
作者：
Bai, Ruibing;Wang, Junfeng;Zhang, Yanqiang
主要观察和结论总结：使用羟基功能离子液体（IL）作为助萃取剂，磷酸三丁酯（TBP）作为萃取剂从高镁/锂比盐水中萃取Li+。首先，萃取体系1-(2-羟乙基)-3-甲基咪唑鎓双(三氟甲基磺酰基)亚胺([HOEmim][NTf2]) + TBP被证明在不同IL、TBP和IL组成的萃取剂中从LiCl水溶液中萃取Li+的效率最高(88.15%) + 待定。然后研究了不同萃取参数对Li+和Mg2+萃取效率的影响。在278.15 K、O/A为2:1的条件下，Li+的单级萃取率达到95.01%，Li/Mg分离因子达到405.76。通过斜率分析法和ESI-MS分析确定萃取配合物，表明有机相中的金属配合物主要为[Li中心点2TBP][NTf2]。剥离研究表明，92.86% 的 Li+ 被 1.0 mol 中心点 L-1 HCl 剥离。协同萃取剂在5次再生循环后仍保持98%的萃取能力。最后进一步论证了热力学参数（Delta G 度、Delta H 度和 Delta S 度）以及 Li+ 提取的机理。结果表明，[HOEmim][NTf2]+TBP萃取体系在从高Mg/Li比盐湖卤水中萃取锂方面表现出良好的性能。
The Summary of main observation and conclusion: The extraction of Li+ from the high Mg/Li ratio brine was performed using hydroxyl functional ionic liquids (ILs) as the coextractant and tributyl phosphate (TBP) as the extractant. Firstly, the extractive system, 1-(2-hydroxyethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HOEmim][NTf2]) + TBP was proved to exhibit the highest extraction efficiency of Li+ (88.15%) from LiCl aqueous solutions among the extractants composed of different ILs, TBP, and ILs + TBP. Effects of various extraction parameters on the extraction efficiencies of Li+ and Mg2+ were then investigated. 95.01% of Li+ was extracted and the Li/Mg separation factor reached 405.76 in a single-stage at 278.15 K and O/A of 2 : 1. The extraction complexes were determined by the slope analysis method and ESI-MS analysis, and the metal complexes in the organic phase were indicated to be mainly [Li center dot 2TBP][NTf2]. The striping study showed that 92.86% of Li+ was stripped with 1.0 mol center dot L-1 HCl. 98% extraction capacity of the synergy extractants was remained after 5 regeneration cycles. The thermodynamic parameters (Delta G degrees, Delta H degrees, and Delta S degrees), together with the mechanism of the Li+ extraction were further demonstrated finally. According to the results, [HOEmim][NTf2] + TBP extraction system showed promising performance in extracting lithium from salt lake brine with high Mg/Li ratio.