METHOD FOR CLEANING URANIUM CONCENTRATES FROM GADOLINIUM Russian patent published in 2022 - IPC C22B59/00 G21C19/40 

FIELD: chemistry.

SUBSTANCE: invention relates to the chemistry and technology of uranium and can be used to produce high purity uranium oxides in the processing of uranium fuel rods containing gadolinium. The uranium concentrate with an admixture of gadolinium is dissolved in (4-6) M nitric acid, taken in an amount exceeding the stoichiometrically required by at least 20%. The residual acidity of the solution is neutralized with calcium-containing oxide or hydroxide or carbonate or their combination to pH=(1.0-2.5). In the form of a water-soluble compound, a fluorine ion is introduced into the solution in an amount that provides a (1.5-2.0)-fold stoichiometric excess relative to the introduced calcium. An exposure is made until the formation of a precipitate is completed, which can be from 2 to 4 hours, filtered, and uranium is precipitated from the filtrate with ammonia or hydrogen peroxide.

EFFECT: invention makes it possible to purify uranium concentrate from gadolinium by a simple precipitation method, with its high direct recovery and selectivity.

3 cl