Method for removing fluorine from rare earth ore leaching solution

Abstract

This invention belongs to the technical field of rare metal extraction, specifically relating to a method for defluorinating rare earth ore leaching solutions. The steps are as follows: S1, adding ammonium bicarbonate to the rare earth ore leaching solution, clarifying, and then separating the solid and liquid to obtain filtrate A and filter residue A; S2, adding ammonium bicarbonate to filtrate A, separating the solid and liquid to obtain filtrate B and filter residue B; S3, adding concentrated sulfuric acid to filter residue A, adding filtrate B from step S2, separating the solid and liquid to obtain filtrate C and filter residue C; S4, adding oxalic acid solution to filtrate C, stirring and reacting, clarifying, and then filtering to obtain filtrate D and filter residue D; S5, adding calcium or magnesium salts to filtrate D, separating the solid and liquid to obtain CaF2 or MgF2 filter residue and filtrate E; S6, mixing filtrate B and filtrate E, recovering and continuing to use for leaching rare earth ore, with filter residue B and filter residue D being the defluorinated rare earth products. This method can eliminate fluoride ions at the source, improving the subsequent rare earth metal extraction rate and quality.

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