Rare earth magnet electrochemical recycling
Thanks to unique properties, rare earth elements are widely used in industrial products such as magnets, batteries, and lasers, earning the nickname "vitamins of industry". However, rare earth elements are difficult to be separated individually, and the purification process is heavily polluting. Moreover, global rare earth minerals are primarily controlled by a few countries. Our team has developed an innovative electrochemical technology for the recycling NdFeB magnets. This approach effectively recovers rare earth elements to over 99% purity while significantly reducing chemical and energy consumption, aiming to be used as low-carbon resources.
Why is the recycling of Rare earth element important?
In the trend towards international net-zero carbon emissions and clean energy transition, the rapid development of electric vehicles and wind power has led to a significant increase in demand for rare earth elements, which is estimated to grow sevenfold by 2040. Neodymium-iron-boron (NdFeB) magnets, known for their superior performance in synchronous motors and related industrial products, are extensively used. However, traditional high-pollution mining methods are no longer sustainable. Therefore, recycling of rare earth resources has become crucial to meet market demands. Our team has developed an innovative electrochemical technology capable of separating rare earth elements in the form of solid compounds from impurities. This not only simplifies the recycling process and aligns with net-zero trends by providing low-carbon raw materials, but also utilizes our team's expertise in magnetic analysis to reintegrate recycled rare earth materials directly into magnet manufacturing supply chains.
Novel recycling method of Rare earth element from permanent magnet
Traditional methodologies for recycling NdFeB magnets include pyrometallurgy, hydrometallurgy, and electrometallurgy. Pyrometallurgy handles large volumes but is energy-intensive; hydrometallurgy achieves high purity but causes significant liquid waste pollution. Electrometallurgy, based on potential difference principles, allows elements to be separated through electrochemical dissolution or oxidation, resulting in faster reaction rates and lower energy and solvent consumption. Our team has developed an innovative electrochemical technology that combine experimental observation with thermodynamic simulation to achieve selective separation. This approach successfully recovers rare earth elements from NdFeB magnets into oxides compounds with over 99% purity. The time-consuming, energy-intensive, and high-pollution drawbacks of conventional recycling methods are much improved by enhancing process efficiency.
Our ultimate goals for the recycling of rare earth magnets
Our team won the Championship at the 2024 Net Zero Tech International Contest in NTU campus
The "2024 Net-Zero Emissions Technology International Contest @ Taiwan" was inspired by the global commitment to reach net-zero emissions by 2050, which Taiwan has actively responded to with the release of the "2050 Net-Zero Emissions Roadmap" in 2022. To promote the cultivation of talent in net-zero technology, the TECO Technology Foundation and National Taiwan University jointly organized this international event, aiming to lay a foundational understanding for a sustainable future for both Taiwan and the planet.
This year’s competition attracted an impressive 240 entries from 13 countries. A team from National Tsing Hua University's Department of Materials Science and Engineering, led by Prof. Chih-Huang Lai and team captain Shao-Chi Lo, stood out among the many participants and won the main competition championship. In the final round, Lo delivered a clear and concise presentation of complex technological concepts, and his excellent presentation skills, combined with the team’s innovative work, were highly praised by the judges.
Lo shared that the team invested significant time in refining their presentation materials and perfecting their project to meet the competition's high standards. He views this experience as not only a testament to the team's abilities but also a valuable opportunity for learning and growth. Lo's entry was based on his long-standing research on the recycling and purification of rare earth materials. He believes that the development of this technology can contribute to Taiwan’s environmental goals, carbon reduction, economic growth, and geopolitical interests. His advisor, Professor Chih-Huang Lai, along with postdoctoral researcher Tzu-Min Cheng, also supported this research direction and provided considerable assistance to the team throughout the competition. Lo hopes that through this competition, he can inspire younger students to engage in the field of net-zero technology and collectively contribute to the sustainable development of the planet.