An ionic liquid extractant dissolved in an ionic liquid diluent for selective extraction of Li(I) from salt lakes
An ionic liquid extractant dissolved in an ionic liquid diluent for selective extraction of Li(I) from salt lakes
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DOI：
10.1016/j.desal.2021.115073
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发表时间：
2021-04-10
期刊：
影响因子：
9.9
通讯作者：
Goto, Masahiro
中科院分区：
文献类型：
--
作者：
Cai, Chunqing;Hanada, Takafumi;Goto, Masahiro
从盐湖中有效回收锂（Li(I)）是目前一个具有挑战性的问题。在此，我们报告了一种可行的提取系统，从模拟盐湖溶液中提取Li(I)，使用一种新的提取系统，其中功能化离子液体（FIL）溶解在不同的离子液体稀释剂中。成功制备了3-甲基-1-辛基咪唑酰三氟丙酮[Omim][TTA]作为功能萃取剂，并对其对Li(I)的萃取性能进行了评价。系统地考察了pH、金属浓度对萃取及汽提性能的影响。研究发现，在较宽的pH范围内，甚至在酸性条件下，FIL都能有效地作为Li(I)的萃取剂。在离子液体稀释剂中，其萃取能力明显增强。结果表明，即使在五循环重复使用试验中，Li(I)也能从水溶液中提取到离子液体中，萃取效率很高。此外，在模拟盐湖溶液中，Li(I)被选择性地提取，Na(I)的分离系数高达227，而Na(I)和K(I)则保留在水溶液中。
An efficient recovery of lithium (Li(I)) from salt lakes is currently a challenging issue. Herein, we report a feasible extraction of Li(I) from a simulated salt lake solution using a novel extraction system, in which a functionalized ionic liquid (FIL) is dissolved in a different ionic liquid diluent. As a functional extractant, 3-methyl-1-octylimidazolium thenoyltrifluoroacetone [Omim][TTA] was successfully prepared in a simple way and its extraction performance for Li(I) was evaluated. The effects of pH and metal concentration on extraction, as well as the stripping property, were systematically investigated. It was found that the FIL could effectively act as the extractant of Li(I) over a wide range of pH, and even under acidic conditions. The extraction ability of the FIL was markedly enhanced by its use in an ionic liquid diluent. The obtained results demonstrated that Li(I) was extracted from the aqueous solution into the ionic liquids with a high extraction efficiency even in a five-cycle reusability test. Furthermore, using a simulated salt lake solution, Li(I) was selectively extracted with a high separation factor of 227 over Na(I), whereas Na(I) and K(I) remained in the aqueous feed solution.