Ionic‐Liquid‐Supported Magnetic Nanoparticles: Synthesis, Characterization, and Their Use for the Separation of Co and Ni from Li in Aqueous Solutions.

The evolution of the electric vehicle market and the ongoing demand for lithium (Li), cobalt (Co) and nickel (Ni) for batteries production requires secondary sources for obtaining these elements. The recycling of Li‐ion batteries involves hydrometallurgical processes with potential environmental implications, hence there is an urgent need for sustainable and more efficient recycling methods. Functionalized colloidal magnetic nanomaterials have gained interest as sorbents as they can selectively bind and remove metal species from waters, allowing their easy recovery through magnetic separation. This work addresses the preparation and evaluation of silica‐coated magnetite nanoparticles (NPs), as alternative materials to recover Co and Ni from aqueous media, after their surface modification with 1‐methyl‐3‐propylimidazolium chloride. The magnetic nanosorbents were fully characterized and the influence of solution pH and amount of ILs on the NPs surface was evaluated. Our research allows us to conclude that IL functionalized magnetic nanoparticles can be explored as an alternative to hydrometallurgical processes for the separation of Co and Ni from alkaline lixiviates of spent lithium‐ion battery (LIB) powders. [ABSTRACT FROM AUTHOR]