Since the 1970’s, solvent extraction in hydrometallurgical processes has been the enabling technology in the production of high-purity metals. Examples include copper, rare earth oxides, uranium, cobalt and nickel. Notwithstanding incremental improvements in extractant formulations, few breakthroughs can be recounted in this industry outside of the initial amine-, oxime- or phosphine-based reagent chemistries. However, the advent of lithium-ion batteries and their stringent requirements for critical materials (lithium, cobalt, nickel) offer new challenges and opportunities for solvent extraction. Solvay has recently introduced three new extractants: CYANEX®572 for rare earths, CYANEX®600 for molybdenum, CYANEX®936 for lithium, all of which provide a step change in metal separation performance and selectivity. Solvay has also developed unique modeling software capabilities in cobalt/nickel separation using CYANEX®272, zinc solvent extraction using DEHPA® and rare earth separations using CYANEX®572. This paper presents these advances and summarizes the technical and economic benefits demonstrated in the laboratory and commercial applications.