Research Advances in Solvent Extraction of Lithium: The Potential of Ionic Liquids

Abstract The proliferation of Li‐related technologies, especially in the electronic devices and transportation sectors, has exacerbated the global Li resource gap. In response, significant efforts have been directed toward enhancing access to this valuable resource. Recently, numerous studies have highlighted solvent extraction as a straightforward, economical, and environmentally friendly approach for Li extraction and separation. Among them, ionic liquids (ILs) as highly tunable design solvents have garnered considerable attention for their exceptional properties compared to traditional organic solvents, yet their associated extraction systems have albeit with only moderate advancements over the past few decades. To this end, this review initiates an investigation into the pioneering research on the utilization of ILs as diluents, primary extractants, and co‐extractants for Li extraction and separation. Afterward, a comprehensive review is presented on the extraction behaviors of diverse ILs, primarily encompassing cation‐exchange and ion‐association mechanisms. The challenges faced in the application of ILs by solvent extraction are discussed. Meanwhile, Industrial technology such as patents and prospects of ILs are examined, paving the way for future directions in the development and application of ILs within Li solvent extraction technologies.