作者：Xiaorui Zhu, Lingyu Zhu, Jianli Wang, Jiayuan Wang
关键字：COSMO, extraction, ionic liquid, LCST, salting-out
论文来源：期刊
具体来源：AICHE JOURNAL
发表时间：2024年

本研究旨在开发一类基于有机膦酸的新型离子液体（ILs），其特有的热致相变行为可精准适配均相液液萃取需求，旨在解决传统离子液体高粘度带来的应用限制。本工作的创新性体现在两方面：（1）建立了基于logP参数的溶剂设计准则，用于构建热致相变型水/有机膦酸离子液体体系；（2）完成了该体系在均相液液萃取领域的原理验证研究。具体而言，本研究通过系统探索四烷基铵阳离子与有机膦酸基阴离子的多种组合，成功制备出系列新型离子液体，该系列材料在水溶液中展现出独特的低临界溶解温度（LCST）特性。进一步通过金属离子与酸性物质的萃取案例，实证了此类热致相变溶剂体系的实际应用效能。研究同时深入探讨了均相萃取模式的技术优势及其受盐析效应制约的局限性。

The objective of this study is to develop ionic liquids (ILs) derived from organophos-phorus acids, featuring thermomorphic phase behavior tailored for homogeneousliquid–liquid extraction applications, addressing the challenges posed by the high vis-cosity of ILs. The novelty of our work includes a logP-based guideline for designingthermomorphic water/organophosphorus IL solvent systems and a proof-of-conceptstudy on homogeneous liquid–liquid extraction applications. Specifically, we reporteda series of novel ILs exhibiting lower critical solution temperature behavior in aque-ous solutions by exploring various combinations of tetraalkylammonium cations withorganophosphorus acid-based anions. Practical applications utilizing this type of ther-momorphic solvent system for extracting metal ions and acids were demonstrated.The benefits of homogeneous extraction, as well as the limitations stemming fromthe salting-out effect, were presented and discussed.

图1 基于热致相变溶剂体系的均相液液萃取（HLLE）工作原理示意图，分别展示：(A) 具有上临界溶液温度（UCST）行为；(B) 具有下临界溶液温度（LCST）行为的溶剂体系。