Makale detayı · 2026
Selective extraction of rare earth elements from end-of-life NdFeB magnets via low-temperature NH 4 Cl-based chlorination roasting and water leaching
Canadian Metallurgical Quarterly
- Yıl
- 2026
- ISSN
0008-4433- Tür
- article
Veri kaynağı ayrımı
- YÖKSİS YÖKSİS makale kaydı
- OpenAlex OpenAlex zenginleştirmesi (özet, atıf, konular)
Özet
İngilizce (OpenAlex)
Neodymium–iron–boron (NdFeB) magnets are critical components in the transition to a low-carbon energy economy due to their superior magnetic properties. They have significantly higher rare earth element (REE) content (25–35%) compared to natural resources (0.15–2%), making end-of-life NdFeB magnets a valuable secondary REE source. In this study, the selective recovery of REEs from end-of-life NdFeB magnets was investigated using water leaching following chlorination roasting with NH4Cl. A series of experiments was conducted to evaluate the effect of NH4Cl on the NdFeB magnet ratio, roasting temperatures, and roasting duration. Under optimal conditions (300°C, 3 h, NH4Cl at twice the stoichiometric requirement), the roasted products were subjected to water leaching (500 rpm, 90°C, liquid – solid ratio of 20 mL/g, 1 h). resulting in over 95% REE dissolution. Rare earth oxalates were precipitated from the pregnant leach solution with 90% efficiency using 1.5 times the stoichiometric requirement of oxalic acid. Subsequent calcination at 850°C for 2 h yielded rare earth oxides with 99.8% REE purity. Moreover, the dissolution of iron was effectively suppressed through a simple two-stage Fe(OH)3 precipitation step, providing a more economical and selective recovery route.
Konular
- Extraction and Separation Processes
- Geochemistry and Elemental Analysis
- Metal Extraction and Bioleaching
Birincil konu Extraction and Separation Processes