About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Rare Metal Extraction & Processing
|
| Presentation Title |
Recycling of end-of-life NdFeB magnets using sulfation roasting, water leaching, and precipitation |
| Author(s) |
Pushpa Gautam, Shreyas Prashant Kadam, Jayasree Biswas |
| On-Site Speaker (Planned) |
Pushpa Gautam |
| Abstract Scope |
The efficient recycling of rare earth elements (REEs) from NdFeB magnet waste is critical for sustainable resource management. This study investigates the selective recovery of REEs via sulfation roasting, water leaching, and precipitation. Systematic experiments were conducted on crushed and demagnetized NdFeB magnet powders, with roasting performed under varying SO₂/O₂ atmospheres, gas flow rates, and temperatures (500–800°C). At high roasting temperatures, suboptimal REE recovery is observed due to the formation of RE oxides. The Factsage phase diagram analysis predicted, and experiments confirmed, that selective REE sulfation is favoured between 600-700°C, while higher temperatures promote oxide formation and lower temperatures favour non-selective sulfation. SEM-EDS analyses demonstrated the formation of REE-sulfate-rich rims and iron oxide cores at optimal conditions. Water leaching at room temperature yielded a threefold increase in REE extraction efficiency with minimal iron dissolution. The integrated approach presented here establishes a robust framework for advancing sustainable REE recovery technologies. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Recycling and Secondary Recovery, Pyrometallurgy, Hydrometallurgy |