PROCESS FOR PRODUCING RARE METAL

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Residue solutions produced from leaching a mineral resource and extracting a primary target therefrom may contain impurities such as Fe and Al. The present invention relates to a process for extracting rare-earth metals from residue solutions with reduced impurities. The process comprises : recovering a residue solution wherein the residue solution is produced from leaching a mineral resource and extracting a primary target metal therefrom; adjusting the pH to pH 5 to pH 11 to generate and recover a precipitate; placing it in an aqueous solution so that the pH is 3 to 5 and then removing a residual- precipitate; adding oxalic acid to precipitate a rare-earth metal oxalate; recovering the rare- earth metal oxalate and then converting it into a rare-earth metal oxide; and electrolyzing in a molten salt to collect in a metallic state a rare-earth metal at a cathode.