METHOD FOR COLLECTING RARE EARTH

摘要

PROBLEM TO BE SOLVED: To provide a method for inexpensively collecting a large amount of rare earths while preventing the contamination due to impurities.

SOLUTION: The collecting method comprises: the first step of supplying a scrap of a rare earth magnet produced in a process of manufacturing the rare earth magnet to a sulfuric acid solution having a concentration of 1.5 to 3.0 mol/L, and dissolving the rare earth in the scrap of the rare earth magnet into the sulfuric acid solution; the second step of removing undissolved components from the sulfuric acid solution obtained in the first step to obtain a solution containing the dissolved rare earth; and the third step of precipitating a rare earth sulfate by adding an ionic substance with a smaller molecular weight than that of the rare earth into the solution obtained in the second step and using a crystallization technique; and the fourth step of collecting the precipitated rare earth sulfate.

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