Separation of neodymium from FeNd alloy and the preparation of porous iron alloy by chemical dealloying in molten chlorides: Application to the recovery of NdFeB wastes

We proposed a simple and high value-added technology for recycling NdFeB waste. Neodymium was successfully separated from FeNd alloy by chemical dealloying reaction FeNd + 2NdCl3 → 3NdCl2 + Fe in molten chlorides. In the dealloying process, the porous iron alloy with small pores (around 10 nm) and high surface area (2 ∼ 20 × 104 cm2 cm−3) was prepared. The separated neodymium can be recycled as metallic neodymium by spontaneous disproportionation 3NdCl2(l) → 2NdCl3(l) + Nd(s). In other words, the FeNd alloy only needs to be dipped in molten chloride to obtain metallic neodymium and porous iron alloy by the chemical dealloying method. And the LiCl-NdCl3 salts can be recyclable.