A magnesium cathode retrieves neodymium from discarded hard-drive magnets
A laboratory recycling method separates neodymium from discarded hard-drive magnets by collecting it in a magnesium alloy. The peer-reviewed study combines an electrochemical recovery step with later magnesium removal. Its results establish a route for one tested waste stream; projected industrial costs and emissions still depend on scale-up assumptions and the electricity supply.
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Neodymium collects in a removable alloy
Discarded hard-drive magnets supplied the material for a laboratory route to recovering neodymium. Researchers used the magnets on the anode side of an electrochemical cell and a magnesium rod on the cathode side. In molten salt, neodymium separated from the magnet and joined magnesium. The resulting liquid alloy dropped away from the rod and collected at the bottom. This arrangement renewed the exposed cathode surface while keeping the product available for collection.[1]
Magnesium removal yields the product
Most of the iron, boron and nickel coating stayed in the anode residue. Removing magnesium from the collected alloy in a later low-pressure heating step yielded the neodymium product. The experiment therefore separates electrochemical collection from obtaining the final material. Its feedstock was a particular class of discarded magnets, leaving other waste compositions and impurities for further tests.[1]
Industrial performance remains a scale-up question
The study also modeled costs and life-cycle emissions for larger production scales. Electricity supply influenced the estimates, with renewable-power scenarios giving lower emissions. Those calculations describe assumed facilities rather than measurements from a running industrial plant. Testing extended operation, enlarging the cell and processing different waste mixtures remain steps between this laboratory demonstration and a deployed recycling process.[1]
