Nd composite selective recovery from waste permanent magnet scrap powders by solid-fluorination reaction

초록

This study proposes a novel waste permanent magnet (WPM) recycling technology by avoiding conventional technology that relies on strong acid and developing a feasible process using relatively inexpensive reagents, thereby reducing overall process cost to acceptable levels. Nd2Fe14B WPMs were transformed into a fluoride/oxide composite material through oxidation/fluorination heat treatment. The phase transition from FeF3-NdF3 to Fe2O3-NdF3 composition was performed via heat treatment. The Fe2O3-NdF3 composition is selectively leached using an oxalic acid. It was confirmed that Fe2O3 was selectively leached, and NdF3 was leached at less than 1 wt.% under various leaching conditions. The neodymium fluoride produced using this technology is expected to be applicable to related fields such as Nd smelting flux or catalysts, and this technology is expected to be applied to various materials containing Fe.

키워드