METHOD FOR EXTRACTING RARE EARTH METALS FROM PRODUCTIVE SOLUTIONS IN SULFURIC ACID LEACHING OF URANI

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FIELD : metallurgy. SUBSTANCE : invention relates to hydrometallurgy of rare metals, in particular, to a method for extracting rare earth metals (hereinafter REM) from productive solutions in the sulfuric acid leaching of uranium ores. Method for extracting REM includes sorption of rare-earth metals on a strongly acid cation exchanger, regeneration of a saturated sorbent and precipitation of a concentrate of REM from strippant. Return sorption solution of uranium is passed through a strongly acidic cation exchanger, the desorption of impurities is carried out with a solution of sulfuric acid along with the desorption of rare-earth metals with a solution of ammonium sulfate with the separation of REM strippant into commodity and tail fractions. Precipitation of rare-earth metals from the marketable fraction is carried out in three stages, while the first stage is carried out by precipitation of rare-earth metals and impurities with a solution of ammonia at pH 7.3–7.8 with the separation of iron(II), which is left in solution. Obtained primary concentrate is dissolved in nitric acid, in the second stage from the nitric acid solution, impurities are precipitated with ammonia solution at pH 4.5–5.0, in the third stage, REM concentrate is precipitated with ammonium carbonate at pH 6.0–7.0. EFFECT : technical result is to increase the extraction of rare-earth metals and reduce the content of impurities in the concentrate of rare-earth metals. 9 cl, 2 tbl, 1 ex