| abstract |
The invention relates to a method for treating spent nuclear fuel, which includes (a) decontaminating the uranium, plutonium and neptunium found in a nitric aqueous phase resulting from dissolving said nuclear fuel in HNO 3 , with regard to the actinides (III) and the majority of the fission products also found in said phase, said decontamination including at least the co-extraction of the uranium, plutonium and neptunium in a solvent phase; (b) splitting the uranium, plutonium and neptunium found in the solvent phase in a first aqueous phase containing either plutonium with no U or Np, or a mixture of Pu and U with no Np, or a mixture of Pu, U and Np, and a second aqueous phase containing either a mixture of U and Np with no Pu, or uranium with no P or Np; (c) storing the first aqueous phase; (d) purifying the plutonium or the mixture of Pu and U or the mixture of Pu, U and Np found in the first aqueous phase relative to the fission products still found in said phase, said purification including at least one addition of uranium, in order to obtain, at the end of said purification, an aqueous solution containing a mixture of Pu and U or Pu, U and Np; and (e) co-converting the resulting mixture of Pu and U or the mixture of Pu, U and Np into a mixed oxide. |