Development of thermomorphic ionic liquids derivedfrom organophosphorus acids for homogeneousextraction processes
作者：Xiaorui Zhu, Lingyu Zhu, Jianli Wang, Jiayuan Wang
關鍵字：COSMO, extraction, ionic liquid, LCST, salting-out
論文來源：期刊
具體來源：AICHE JOURNAL
發表時間：2024年
本研究旨在開發一類基于有機膦酸的新型離子液體（ILs），其特有的熱致相變行為可精準適配均相液液萃取需求，旨在解決傳統離子液體高粘度帶來的應用限制。本工作的創新性體現在兩方面：（1）建立了基于logP參數的溶劑設計準則，用于構建熱致相變型水/有機膦酸離子液體體系；（2）完成了該體系在均相液液萃取領域的原理驗證研究。具體而言，本研究通過系統探索四烷基銨陽離子與有機膦酸基陰離子的多種組合，成功制備出系列新型離子液體，該系列材料在水溶液中展現出獨特的低臨界溶解溫度（LCST）特性。進一步通過金屬離子與酸性物質的萃取案例，實證了此類熱致相變溶劑體系的實際應用效能。研究同時深入探討了均相萃取模式的技術優勢及其受鹽析效應制約的局限性。
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.
圖1 基于熱致相變溶劑體系的均相液液萃取（HLLE）工作原理示意圖，分別展示：(A) 具有上臨界溶液溫度（UCST）行為；(B) 具有下臨界溶液溫度（LCST）行為的溶劑體系。