The current status of recycling technology for waste NdFeB resources

Abstract

Neodymium-iron-boron (NdFeB) permanent magnet materials are widely used and critical due to their resource scarcity, making the recycling of NdFeB waste a pivotal issue for sustainable development. This study reviews four key recycling methods: hydrometallurgy, pyrometallurgy, electrometallurgy, and direct recycling. Hydrometallurgy achieves high purity and flexibility but involves significant chemical use and environmental impact. Pyrometallurgy suits high-grade waste with a simple process but is energy-intensive. Electrometallurgy is eco-friendly but limited by high costs and complexity. Direct recycling, efficient and straightforward, is suitable for intact waste but less effective for complex materials. This study underscores the need to evaluate recycling technologies comprehensively, considering critical metrics such as recovery rate, cost efficiency, and environmental impact, which are often underrepresented in current research. Future advancements should focus on optimizing multi-process integration, developing green reagents and efficient separation technologies, and enhancing the utilization of low-value components to achieve a balance between economic viability and sustainability. These findings provide valuable insights for establishing efficient and eco-friendly NdFeB waste recycling systems.