Recovery of neodymium from neodymium magnet using bismuth

Abstract

Synopsis: Experiments were conducted to extract neodymium in bismuth by melting Fe-Nd-B magnets and bismuth together in a graphite crucible at 1200°C. Molten iron and bismuth separated into two phases, and neodymium in the magnet dissolved in the bismuth phase. Neodymium dissolved in bismuth was considered to form BiNd as a result of XRD. The neodymium concentration in iron phase after the dissolution treatment was 0.05 at.% or less, and the recovery rate was 99% and more. Compared to other metals(Mg, Ag, Cu) that separate into two phases with respect to molten iron, bismuth can be said to be a metal extraction material with a low melting point, safety and low energy cost.