Nd-enriched particles prepared from NdFeB magnets: A potential separation route

The preparation of Nd-enriched particles from NdFeB sintered magnets using no acid or basic solution is reported. The combination of a hydrogenated-disproportionated alloy with a H2O2 solution at room temperature allows that Nd(OH)3 be obtained as major phase whilst Fe concentration is reduced 27 times compared to the starting material. The chemical reactions which take place in the system during the reaction are proposed based on X-ray diffraction results. After an oxidizing heat treatment a mixture of neodymium oxides is achieved.