Neodymium magnets are among the strongest permanent magnets in the world. They are made from neodymium, iron and boron, and are used in electric vehicles, wind turbines, as well as in speakers, smartphones and hard drives. Global demand for permanent magnets is growing: annual growth is estimated at up to 8.3%. Therefore, recycling rare earth elements such as neodymium is becoming increasingly important, although the process itself is very complex.
For neodymium to be reused in new magnets, it must be very pure. Creating an economically viable process that ensures such purity is not easy. As a result, only a very small share of magnets is recycled in Europe. Most are collected and sent to China for recycling, and then about 90% of the materials, including neodymium, are returned to Europe.
As part of the EU-funded NEO-CYCLE project, researchers are working to recover valuable materials directly in Europe. Sandra Pavon, head of the hydrometallurgical processing and raw materials chemistry group at the Fraunhofer IKTS institute in Freiberg, says: "We aim to extract rare earth elements from electronic waste and use them in high-value products such as green fertilizers and pharmaceuticals. This will close the materials loop, protect the environment and help reduce global dependence on strategic resources."
The project focuses on hard disk drives (HDDs) from discarded computers and laptops, which contain neodymium magnets. Researchers are testing two recycling methods: solid-phase chlorination and an electrochemical process. In the first case, ammonium chloride is added to the neodymium-boron-iron mixture obtained from HDD waste instead of the usual hydrochloric acid. When heated, the mixture turns into metal chlorides and a high-purity ammonia solution. This patented method is already used for fluorescent lamps, and scientists are now checking whether it is suitable for magnets. The results show that metal chlorides can be separated from the magnet material much more efficiently, extracting almost all metals using a relatively small amount of chemicals.
In the second method, powdered magnet waste is placed in an electrochemical cell, where an electrolyte, such as dilute sulfuric acid, serves as the medium for reactions. First, a boron solution is extracted from the magnets, which is then concentrated for use in the chemical and pharmaceutical industries.
Fraunhofer IKTS specialists then separate the products of both processes using their expertise in metal separation and process water purification. Using a selective hydrometallurgical method (that is, selective extraction of metals from solutions), they isolate neodymium and iron, and then obtain metal salts in pure form. After separation, the materials are further purified by the project partners and supplied not only to the chemical and pharmaceutical industries, but also to the hydrogen and fertilizer sectors.
Although the research demonstrates promising laboratory results, it is too early to speak of industrial implementation and commercialization timelines. Nevertheless, if the technology proves economically viable, it could become a step toward reducing Europe's dependence on imports of rare earth metals.