Alternative Extraction Systems for Precious Metals Recovery: Aqueous Biphasic Systems, Ionic Liquids, Deep Eutectic Solvents

The current trend in the development of separation methodologies implies their evolution in an environmentally friendly perspective, more precisely, the transition to techniques, materials, and solvents that could be qualified as greener alternatives to conventional ones. The green extraction systems can be attributed to aqueous biphasic systems, ionic liquids, and deep eutectic solvents, which have been widely used recently for various analytical, synthetic, and industrial tasks. In this chapter, the features of the listed systems are discussed in relation to the extraction of precious metals, mainly platinum, palladium, and gold; the examples of the alternative extraction systems for separation and preconcentration of precious metals are reviewed.