University project reclaims rare earth magnets from loudspeakers and flat panel displays

The University of Birmingham in the UK has announced the successful completion of a project demonstrating that the rare earth magnets in loudspeakers and flat panel displays, which are currently lost to landfill, can be successfully recycled.

image: Shutterstock/mstanley

Loudspeakers account for approximately 20% of rare earth magnet use, and represent a significant opportunity for rare earth magnet recycling, particularly in the UK, which has no domestic source of primary rare earth metals.

The Rare-Earth Extraction from Audio Products (REAP) project was led by HyProMag, a company set up by Professor Allan Walton from the School of Metallurgy and Materials with founding directors Professor Emeritus Rex Harris, former head of the university’s Magnetic Materials Group and two Honorary Fellows, Dr John Speight and David Kennedy, who are experts in the field. The REAP project also involved European Metal Recycling, which has a global footprint in metal recycling and sustainability. 

REAP used a patented recycling technology called hydrogen recycling of magnet scrap (HPMS) that was developed within the university to extract and de-magnetise the neodymium iron boron (NdFeB) alloy powders embedded in loudspeakers from end of life cars and flat screen TVs. The alloy powders were then purified, and re-compacted to produce new magnets that had magnetic properties comparable to the initial starting magnet. The project also confirmed the quantity and economics of recycling loudspeaker magnets, and provides a strong platform to scale up production.

European Metal Recycling performed a comprehensive assessment of scrap, encompassing extraction, characterisation of components, degree of pre-processing and potential for automation.

Meanwhile, HyProMag and the University of Birmingham provided analysis of the extracted magnets focusing on determining the recyclability and market potential, both as a viable feedstock of NdFeB and also as a potential route-to-market.

The analysis showed that the flat screen television sector holds significant promise for recycling, with approximately 85% of the products containing NdFeB. REAP confirmed the quantity of scrap available from this market, the commercial viability, the suitability of material for HPMS, the properties of the magnets in this sector and provides a strong platform to initiate access to the wider loudspeaker market in the future.

Scrap from end of life vehicles showed a relatively low quantity (~5%) of NdFeB containing components, but given the increase in rare earth use in hybrid and electric vehicles, it is clear that the potential for capturing NdFeB from this sector will increase significantly with time.

Despite the differences between the two sectors, the average magnet grade remained fairly consistent. Following extraction and processing, the resulting powders were analysed to confirm the feasibility of using waste from flatscreen televisions as feedstock for recycled magnet making.

The REAP project was funded via a grant from the Industrial Strategy Challenge Fund, delivered by UK Research and Innovation.

Article Categories

Most Viewed