PROCESSING METHOD OF IRRADIATED NUCLEAR FUEL OF NUCLEAR POWER PLANTS Russian patent published in 2012 - IPC G21F9/00 

FIELD: power industry.

SUBSTANCE: invention refers to processing methods of irradiated nuclear fuel (INF) of nuclear power plants (NPP) and is intended to localise zirconium in 1 extraction cycle by combined extraction of uranium, neptunium, plutonium, technecium and zirconium with selective re-extraction of the latter. Processing method of INF of nuclear power plants involves extraction of uranium (VI), plutonium (VI), neptunium (VI), technecium (VI) and zirconium (VII) with solution of diluted tributyl phosphate and re-extraction of zirconium to solution with nitric acid with cleaning by means of extractant from actinides. Extraction is performed in presence of Cr(VI) at molar ratio of chrome(VI):zirconium(IV)>1, and re-extraction is performed from extract containing all those elements to solution with nitric acid with concentration of zirconium, together with technecium or selectively, at introduction of non salt-forming reducing agent not causing plutonium re-extraction.

EFFECT: complete extraction of zirconium at extraction stage, as well as improvement of neptunium extraction in centrifugal extraction units and pulse columns.

4 cl, 1 dwg, 2 tbl, 4 ex