METHOD OF CLEANING REGENERATED URANIUM Russian patent published in 2011 - IPC C01G43/00 B01D11/04 

FIELD: chemistry.

SUBSTANCE: method of cleaning regenerated uranium from thorium, technetium and neptunium, involves extraction of uranyl nitrate from aqueous nitric acid solution with tributylphosphate in an organic diluent. During multi-step countercurrent extraction at the step for output of the extract, the degree of saturation of the extraction agent with uranium is kept not higher than 92.5% of the limiting saturation and equilibrium concentration of nitrate in the aqueous phase is kept not higher than 0.7 mol/l. Concentration of nitric acid in the first stream of the feed aqueous uranyl nitrate solution, fed at the step for output of the extract, is kept not higher than 0.6 mol/l and saturation of the extraction agent with uranium is kept not higher than 92.5% of the limiting saturation at the third or next step, towards the aqueous phase, when the second feed stream of the aqueous uranyl nitrate solution is being fed.

EFFECT: high degree of purity of uranium.

5 cl, 5 tbl, 1 ex