Application of ionic liquids in solvent extraction of platinum group metals

The advantageous properties of ionic liquids (ILs) have put them in the spotlight in recent years as durable and environmentally friendly solvents compared with conventional organic solvents. The applications of ILs have been expanding in various fields, including extraction and separation of metals. Platinum group metals (PGMs) are attractive targets for recovery using IL systems. In recent years, ILs have shown excellent performance for PGM extraction. In this review, we focus on the recent progress in solvent extraction using ILs for PGM recovery. Although application of ILs in PGM recovery is still in the early stages, research and development of ILs in this area are steadily advancing owing to the unique properties of ILs, such as their non-volatility, inflammability, low toxicity, and tunability. Fundamental approaches are expected to realize industrial applications of ILs in the future.