Heo Nam Jung, Oh Ju Hyun, Li Aimin, Lee Kyounghoon, He Qing, Sessler Jonathan L, Kim Sung Kuk
Department of Chemistry, Research Institute of Natural Sciences, Gyeongsang National University Jinju 52828 Korea
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University Changsha 410082 P. R. China.
Chem Sci. 2024 Aug 12;15(34):13958-65. doi: 10.1039/d4sc03760j.
Improved methods for achieving the selective extraction of lithium salts from lithium sources, including rocky ores, salt-lake brines, and end-of-life lithium-ion batteries, could help address projected increases in the demand for lithium. Here, we report an ion pair receptor (2) capable of extracting LiCl and LiBr into an organic receiving phase both from the solid state and from aqueous solutions. Ion pair receptor 2 consists of a calix[4]pyrrole framework, which acts as an anion binding site, linked to a phenanthroline cation binding motif ether linkages. Receptor 2 binds MgBr and CaCl with high selectivity over the corresponding lithium salts in a nonpolar aprotic solvent. The preference for Mg and Ca salts is reversed in polar protic media, allowing receptor 2 to complex LiCl and LiBr with high selectivity and affinity in organic media containing methanol or water. The effectiveness of receptor 2 as an extractant for LiCl and LiBr under liquid-liquid extraction (LLE) conditions was found to be enhanced by the presence of other potentially competitive salts in the aqueous source phase.
改进从锂源（包括岩石矿石、盐湖卤水和废旧锂离子电池）中选择性提取锂盐的方法，有助于应对预计增加的锂需求。在此，我们报告了一种离子对受体（2），它能够将LiCl和LiBr从固态和水溶液中萃取到有机接收相中。离子对受体2由杯[4]吡咯骨架组成，作为阴离子结合位点，通过醚键连接到菲咯啉阳离子结合基序。在非极性非质子溶剂中，受体2对MgBr和CaCl的结合选择性高于相应的锂盐。在极性质子介质中，对Mg和Ca盐的偏好发生逆转，使得受体2在含有甲醇或水的有机介质中能够以高选择性和亲和力络合LiCl和LiBr。发现在液 - 液萃取（LLE）条件下，水相源相中存在其他潜在竞争性盐会增强受体2作为LiCl和LiBr萃取剂的有效性。
