ABSTRACT
This chapter explores an overview of the new insights into the recovery of strategic and critical metals by solvent extraction. In principle, the separation of metals by hydrometallurgical processes such as solvent extraction can achieve these outcomes due to ambient-temperature operation and the maintenance of materials balance through reagent recycling. Particular attention is paid to explaining how it is possible to improve existing processes by playing both on the chemistry and the flowsheet design. The performance of solvent extraction processes mainly relies on the properties of extractant molecules for the selectivity needed for increasingly challenging problems. The types of amphiphiles used in solvent extraction experiments can assemble into nanoscale structures allowing hydrophilic and hydrophobic environments to coexist. Solvent extraction processes may undergo stresses such as radiolysis or chemical degradation. The extraction and valorization of metals is presently more difficult than in the past because of the complexity of the new resources to process.
