Mechanical activation induced treatment for the synergistic recovery of valuable elements from spent NdFeB magnets

The efficient and sustainable recovery of rare earth resources from spent NdFeB magnets has received considerable and increasing attention. However, the currently prevalent NdFeB magnets recovery techniques focus only on the recovery for rare earth elements (REEs), some of which also recover cobalt (Co) or boron (B). Herein, a simple mechanochemical strategy was proposed to recover REE, Co, and B from spent NdFeB magnets by mixing the NdFeB magnets powder and FeCl₃ 6H₂O through the grinding-roasting-water leaching technological route. The results indicated high leaching efficiencies of 98.94 % for REEs, 99.99 % for Co, and 93.36 % for B from the NdFeB magnets. Additionally, iron remains in the leaching residue as iron oxide (96.73 wt %), achieving the complete separation of REEs, Co, B, and Fe. This mechanochemical based technology offers a green and efficient recovery process, facilitating more effective synergistic recovery of valuable elements from spent NdFeB magnets.