An overview of NdFeB magnets recycling technologies

Rare earth (RE) permanent magnets are essential components for successful green and digital transition. This paper extensively reviews the properties, recycling potential, and critical raw material state-of-the-art recycling technologies of waste permanent NdFeB magnets (containing about 15–30 wt% REE with high economic value). It also discusses different recycling techniques' fundamentals, benefits, and drawbacks, including pyrometallurgy, hydrometallurgy, electrochemistry, direct recycling, and hybrid processes. This has led to the prospecting of the future development direction of NdFeB waste recycling and the presentation of the research idea of avoiding the drawbacks of individual recycling methods through a combined process. Low energy consumption, minimal environmental risks, and a closed-loop system are suggested to be the three primary objectives of the recycling process.