Method of Plutonium Reduction.

摘要

1,156,044. Plutonium reduction; processing spent nuclear fuel. GESELLSCHAFT FUER KERNFORSCHUNG m.b.H. 26 Sept., 1966 [9 Oct., 1965], No. 42794/66. Heading G6R. Pu (IV) is reduced to Pu (III) in aqueous or organic solution by the addition of a nitrite, the acid content of the final solution being below 0À5 M. When an organic solution containing Pu(IV) is contacted with an aqueous nitric acid solution containing sodium nitrite, the Pu is reduced and extracted into the aqueous phase. The organic solution may be a tributyl phosphate-hydrocarbon solution containing U and Pu obtained in the reprocessing of nuclear fuel. According to the concentration of nitric acid and sodium nitrite, U is either extracted with the Pu or remains behind in the organic phase. Addition of sodium nitrate improves the separation of Pu and U. If the acidity of the aqueous solution containing Pu (III) is increased to 1-3 M, oxidation back to Pu (IV) takes place.