The University of Birmingham has managed to recycle rare earths from discarded speaker magnets and repurpose them as brand new magnets.
Rare earths like the well-known neodymium have the part ‘rare’ in the description for a reason, of course. After all, they are relatively rare. It is therefore all the sadder that a lot of this expensive material – which is often mined in conflict areas or other politically less stable environments – simply ends up on landfills after being discarded. Magnets made of rare earths (or at least having them as an ingredient) can be found in speakers, cars and much more. Speaker magnets gobble up about 20% of the total use of rare earths. Which makes them especially interesting as a recycling target.
From old to new
On Hifi Pig we read that the University of Birmingham has successfully completed the REAP project. The letters REAP stand for Rare-Earth Extraction from Audio Products. The project was carried out under the auspices of the HyProMag company set up by Prof. Allan Watsons. A patented method called HPMS was used as the recycling method. Where HPMS stands for hydrogen recycling of magnet scrap. In this process, neodymium-iron-boron (NdFeB) is recovered and demagnetized from end-of-life speakers from, for example, flat TVs and cars. The resulting powder is then purified and re-compressed, after which a new magnet is formed with similar properties to the magnet from which the source material was made. This opens up interesting prospects, we think.