METHOD FOR RECOVERING RARE-EARTH ELEMENT

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A method for recovering a rare-earth element is provided in which a bauxite residue containing a rare-earth element is used as a raw material and the rare-earth element in the bauxite residue can be efficiently recovered. The method for recovering a rare-earth element is a method in which a bauxite residue yielded as a by-product in the Bayer process is used as a raw material, and is characterized by using the bauxite residue having a specific surface area of 35 m2/g or larger, adding a leaching liquid comprising an aqueous solution of one or more mineral acids selected from sulfuric acid, hydrochloric acid, nitric acid, and sulfurous acid to the raw-material bauxite residue to prepare a slurry having a solid/liquid ratio of 2-30 and a pH of 0.5-2.2, leaching the rare-earth element under the temperature conditions of from room temperature to 160ºC, subsequently subjecting the slurry which has undergone the leaching to solid/liquid separation, and then recovering the rare-earth element from the resultant leachate.