Abstract: A method of recycling Ni and/or Co from a functional material such as a battery or catalyst material, the method comprising: forming an acidic aqueous recycling feed of the functional material by acid leaching the functional material or a derivative thereof, the acidic aqueous recycling feed comprising Ni and/or Co in solution; contacting the acidic aqueous recycling feed with an organic solvent extraction composition; and extracting one or both of Ni and Co from the acidic aqueous recycling feed into the organic solvent extraction composition, wherein the organic solvent extraction composition comprises: an organic solvent which is immiscible with the acidic aqueous recycling feed; a picolinic acid ester or picolinic acid amide which is soluble in the organic solvent; and a phase transfer catalyst.

Abstract: A method is described for recycling nickel from waste battery material. The method includes providing waste battery material comprising a nickel-containing oxide, reducing the nickel in the waste battery material to the zero oxidation state to provide a reduced waste battery material, reacting the reduced waste battery material with carbon monoxide to form Ni(CO)4, and reacting the Ni(CO)4 with a source of sulfate to form NiSO4. The NiSO4 product is useful as a nickel feedstock in various processes which require a nickel source, including processes which prepare new battery materials.