Novel rare earth recovery process on Nd-Fe-B magnet scrap by selective chlorination using NH4Cl

Extraction of rare earth elements from the Nd-Fe-B magnet scraps through the chlorination with NH4Cl was performed to study the effective process for reusing metal iron as well as rare earths. The Nd2Fe14B primary phase was selectively converted to NdCl3 in ca. 90% yield, together with α-Fe and Fe-B solid residues by chlorinating at 573 K for 3 h. The resin compacts prepared from the resultant solid residues mainly composed of the α-Fe phase provided the good electromagnetic wave absorption properties.