Satisfactory extractant for the separation of yttrium (Y) from other heavy rare earth elements (HREEs) in dilute solutions has not been reported for the time being. In this article, diethylhexyl phosphinic acid (P227) with lower pK_a value, equilibrium and stripping acidity due to the absence of alkyl oxygen atoms, were incorporated into task-specific ionic liquids (TSILs) to realize the separation of Y. The synthesized [methyltrioctylammonium][di-(2-ethylhexyl) phosphinate] ([A336][P227]) were applied in both solvent extraction and membrane separation processes. Extraction and stripping of HREEs in both hydrochloric and nitric media were studied. A further understanding on the thermodynamics coordination mechanism with rare earths and acid was discussed. Separation factors implied it more suitable for the separation of Y in nitric medium. In addition, from the view of more sustainable and efficient application, polymer inclusion membrane (PIM) was fabricated. Membrane transport was demonstrated from the view of saving reagent and energy. Surface structure and composition analysis were characterized and transport experiments were conducted to verify the separation of Y. Stability and reusability of the PIM were proved well. All these provided the separation of Y from HREEs with a promising novel extractant and membrane separation technology.

暂时还没有令人满意的萃取剂可将稀溶液中的钇（Y）与其他重稀土元素（HREE）分离。在本文中，p K _a较低的二乙基己基次膦酸（P227）由于没有烷基氧原子而产生的酸值，平衡和汽提酸度被结合到特定任务的离子液体（TSIL）中，以实现Y的分离。合成的[甲基三辛基铵] [二-（2-乙基己基）次膦酸酯]（[ A336] [P227]）应用于溶剂萃取和膜分离过程。研究了盐酸和硝酸介质中HREE的提取和汽提。讨论了对稀土和酸的热力学配位机理的进一步理解。分离因子表明它更适合于硝酸介质中的Y分离。另外，从更可持续和更有效的应用的角度出发，制造了聚合物包裹膜（PIM）。从节省试剂和能源的角度证明了膜的运输。表征了表面结构和组成分析，并进行了运输实验以验证Y的分离。PIM的稳定性和可重复使用性得到了很好的证明。所有这些提供了一种有前途的新型萃取剂和膜分离技术，用于从HREE中分离Y。