| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for efficiently recovering the rare-earth elements while repeatedly using a treatment vessel over a long period by restraining the wear of or damage to the vessel.SOLUTION: A recovery method for rare-earth elements includes separating and recovering rare-earth elements as oxides B thereof from iron group elements A by carrying out the heat treatment of an oxidation-treated object in the presence of carbon through two-stage process comprising the following first and second heat treatment steps: the first step of oxidation-treating a treatment object including at least the rare-earth and iron group elements, housing the mixture of the oxidation-treated object and a granular or powdery carbon in a treatment vessel, and heat-treating at a temperature lower than 1,350°C in inert gas atmosphere or in vacuum to obtain a sintered body; and the second step of housing the sintered body obtained by the first heat treatment step in the treatment vessel so that carbon black intervenes at least between the sintered body and a vessel bottom face, and heat-treating the sintered body at 1,350°C or higher in the inert gas atmosphere or in vacuum.SELECTED DRAWING: Figure 3 |
