source：Recycling International
The use of rare earths in the e-mobility sector will surge in the coming decades, according to Ana Maria Martinez of Norway’s R&D firm Sintef. In response, she has been working on a multi-million research project to enable the recycling of magnets ‘at an attractive price’.
Modern vehicles include a range of small magnets that power headlights, electronics and sensors and weigh in at around 250g. These do not include the larger ones inside the catalytic convertor, traction motor or generator.
Strong sales in the consumer electronics sector continue to drive demand for rare earths. Martinez reports that demand for dysprosium, for example, will be almost three times higher by 2030 and six times higher by 2050. Demand for neodymium and praseodymium will be up 50% by 2030 and 150% higher by 2050.
Rich urban mine
‘In short, we are at risk and the inevitable supply bottleneck is a great concern,’ Martinez told delegates at the recent E-waste World Expo. ‘Europe collects around four million tonnes of e-scrap per year. This means that around 370 tonnes of neodymium and 15 tonnes of dysprosium, with a value of EUR 23 million, is available for recycling.’
Extrapolating market figures, the ‘urban mine’ could hold 14 135 tonnes of primary magnets by 2025, growing to 25 325 tonnes by 2030 and 44 500 tonnes by 2050.
Getting the material back can be tricky, though, because they make up only 3% of the weight of a computer (hard drive or optical drive) and less than 0.5% of that of a mobile phone which has no fewer than 14 small magnets.
Rare earth scrap from used air conditioners is expected to reach almost 11 000 tonnes by 2040. Other major sources will be e-bike batteries (10 000 tonnes) and e-car batteries (9 000 tonnes).
Hopeful horizon
‘The big question, is: how do we extract all the rare earths inside these magnets?’ Martinez asks as she introduces the ‘breakthrough’ R&D project she has worked on called REEE4EU. It developed an integrated high temperature electrolysis and ion liquid extraction process to validate ‘a strong and independent European rare earths supply chain’.
The EUR 9 million initiative ran for four years until late 2019 and was funded by the EU’s Horizon 2020 programme. A consortium of 14 industry partners collaborated on a pilot plant at metals and chemicals producer Elkem in Norway, which processed 2 000 tonnes of rare earth scrap using the innovative process.
The rare earth oxide was successfully transformed into rare earth alloys, which were made into strip cast alloys by UK-based project partner Less Com Metals. These were subsequently shipped to German partner Vacuumschmelze, which manufactured new magnets. ‘Our recycled magnets have the exact same properties as virgin magnets,’ Martinez reports.