| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for inexpensively collecting a large amount of rare earths while preventing the contamination due to impurities. <P>SOLUTION: The collecting method comprises: the first step of supplying a scrap of a rare earth magnet produced in a process of manufacturing a magnet, to a sulfuric acid solution having a concentration of higher than 3.0 mol/L but 6.5 mol/L or lower, dissolving at least the rare earth in the scrap of the rare earth magnet into the sulfuric acid solution, and precipitating the dissolved rare earth as a rare earth sulfate; the second step of separating precipitates containing the precipitated rare earth sulfate, from the solution; and the third step of redissolving the precipitates to remove an undissolved component in the precipitates to obtain a rare earth solution containing the dissolved rare earth sulfate. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
