Abstract: A method for cleaning magnetic sliders. One embodiment of the method includes dislodging particulate debris from a surface of a magnetic slider by contacting the surface of the slider with an oscillating brush, enveloping the dislodged particulate debris in a foam, and removing the enveloped particulate debris by removing the foam from the magnetic slider.

Abstract: The use of hydroxyiminoalkanoic acids including at least four carbon atoms as anti-nitrous agents in operations of reductive stripping of plutonium. The invention may be useful in any method for processing spent nuclear fuels that includes one or more operations of reductive stripping of plutonium and, more particularly, in the PUREX method as implemented in modern nuclear fuel processing plants, as well as in processes derived therefrom.

Abstract: The use of hydroxyiminoalkanoic acids including at least four carbon atoms as anti-nitrous agents in operations of reductive stripping of plutonium. The invention may be useful in any method for processing spent nuclear fuels that includes one or more operations of reductive stripping of plutonium and, more particularly, in the PUREX method as implemented in modern nuclear fuel processing plants, as well as in processes derived therefrom.

Abstract: A tray for retaining sliders, such as during washing and/or transporting process steps. The tray has a planar body comprising a top surface having a plurality of cavities therein, an opposite bottom surface having a plurality of recesses therein, and a perimeter. Each cavity is oppositely aligned with a respective recess, with each cavity and its respective recess connected by a passage through the body.

Abstract: A tray for retaining sliders, such as during washing and/or transporting process steps. The tray has a planar body comprising a top surface having a plurality of cavities therein, an opposite bottom surface having a plurality of recesses therein, and a perimeter. Each cavity is oppositely aligned with a respective recess, with each cavity and its respective recess connected by a passage through the body.

Abstract: A method with which uranium from a natural uranium concentrate may be purified, including a) extracting the uranium present as uranyl nitrate in an aqueous phase A1 resulting from the dissolution of the natural uranium concentrate in nitric acid, by means of an organic phase which contains an extractant in an organic diluent; b) washing the organic phase obtained at the end of step a), with an aqueous phase A2; and c) stripping the uranyl nitrate of the organic phase obtained at the end of step b), by circulating this organic phase in an apparatus, as a counter current against an aqueous phase A3. The extractant is an N,N-dialkylamide and the ratio between the flow rate at which the organic phase obtained at the end of step b) and the aqueous phase A3 circulate in the apparatus where step c) occurs, is greater than 1.

Abstract: The invention relates to a process for reprocessing spent nuclear fuel which, among other advantages, does not require a plutonium-reducing stripping operation. This process finds particular application in the processing of uranium oxide fuels and uranium and plutonium mixed oxide fuels.

Abstract: The invention relates to a process for reprocessing spent nuclear fuel which, among other advantages, does not require a plutonium-reducing stripping operation. This process finds particular application in the processing of uranium oxide fuels and uranium and plutonium mixed oxide fuels.

Abstract: The invention relates to the use of butyraldehyde oxime as an anti-nitrous agent in a plutonium stripping operation based on a reduction of this element from oxidation state (IV) to oxidation state (III). Applications: any nuclear fuel reprocessing process in which employing a compound that has the twofold property of being extractable into an organic phase and of being capable of destroying the nitrous acid therein may be useful and especially any process including one or more operations for the reductive stripping of plutonium.

Abstract: A method for treating spent nuclear fuel, which includes first decontaminating the uranium, plutonium and neptunium found in a nitric aqueous phase resulting from dissolving the nuclear fuel in HNO3. The uranium, plutonium and neptunium found in the solvent phase is then split in a first aqueous phase and a second aqueous phase. Next, the first aqueous phase is stored. Following, the plutonium or other mixtures found in the first aqueous phase is purified relative to the fission products still found in said phase, 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. Finally the resulting mixture of Pu and U or the mixture of Pu, U and Np is co-converted into a mixed oxide.

Abstract: A method with which uranium from a natural uranium concentrate may be purified, including a) extracting the uranium present as uranyl nitrate in an aqueous phase A1 resulting from the dissolution of the natural uranium concentrate in nitric acid, by means of an organic phase which contains an extractant in an organic diluent; b) washing the organic phase obtained at the end of step a), with an aqueous phase A2; and c) stripping the uranyl nitrate of the organic phase obtained at the end of step b), by circulating this organic phase in an apparatus, as a counter current against an aqueous phase A3. The extractant is an N,N-dialkylamide and the ratio between the flow rate at which the organic phase obtained at the end of step b) and the aqueous phase A3 circulate in the apparatus where step c) occurs, is greater than 1.

Abstract: A method for treating spent nuclear fuel, which includes first decontaminating the uranium, plutonium and neptunium found in a nitric aqueous phase resulting from dissolving the nuclear fuel in HNO3. The uranium, plutonium and neptunium found in the solvent phase is then split in a first aqueous phase and a second aqueous phase. Next, the first aqueous phase is stored. Following, the plutonium or other mixtures found in the first aqueous phase is purified relative to the fission products still found in said phase, 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. Finally the resulting mixture of Pu and U or the mixture of Pu, U and Np is co-converted into a mixed oxide.

Abstract: The invention relates to a process for reprocessing a spent nuclear fuel and for preparing a mixed uranium-plutonium oxide, which process comprises: a) the separation of the uranium and plutonium from the fission products, the americium and the curium that are present in an aqueous nitric solution resulting from the dissolution of the fuel in nitric acid, this step including at least one operation of coextracting the uranium and plutonium from said solution by a solvent phase; b) the partition of the coextracted uranium and plutonium to a first aqueous phase containing plutonium and uranium, and a second aqueous phase containing uranium but no plutonium; c) the purification of the plutonium and uranium that are present in the first aqueous phase; and d) a step of coconverting the plutonium and uranium to a mixed uranium/plutonium oxide. Applications: reprocessing of nuclear fuels based on uranium oxide or on mixed uranium-plutonium oxide.

Abstract: The invention relates to the use of butyraldehyde oxime as an anti-nitrous agent in a plutonium stripping operation based on a reduction of this element from oxidation state (IV) to oxidation state (III). Applications: any nuclear fuel reprocessing process in which employing a compound that has the twofold property of being extractable into an organic phase and of being capable of destroying the nitrous acid therein may be useful, and especially any process including one or more operations for the reductive stripping of plutonium.

Abstract: The invention relates to a method for separating uranium(VI) from one or more actinides selected from actinides(IV) and actinides(VI) other than uranium(VI), characterized in that it comprises the following steps: a) bringing an organic phase, which is immiscible with water and contains the said uranium and the said actinide or actinides, in contact with an aqueous acidic solution containing at least one lacunary heteropolyanion and, if the said actinide or at least one of the said actinides is an actinide(VI), a reducing agent capable of selectively reducing this actinide(VI); and b) separating the said organic phase from the said aqueous solution. Applications: reprocessing irradiated nuclear fuels, processing rare-earth, thorium and/or uranium ores.

Abstract: A process for reprocessing a spent nuclear fuel and for preparing a mixed uranium-plutonium oxide. The process: a) separates the uranium and plutonium from fission products, americium, and curium that are present in an aqueous nitric solution resulting from dissolution of the fuel in nitric acid, the separating including at least one operation of coextracting the uranium and plutonium from the solution by a solvent phase; b) partitions the coextracted uranium and plutonium to a first aqueous phase containing plutonium and uranium, and a second aqueous phase containing uranium but no plutonium; c) purifies the plutonium and uranium that are present in the first aqueous phase; and d) coconverts the plutonium and uranium to a mixed uranium/plutonium oxide.

Abstract: The invention relates to a process for reprocessing a spent nuclear fuel and for preparing a mixed uranium-plutonium oxide, which process comprises: a) the separation of the uranium and plutonium from the fission products, the americium and the curium that are present in an aqueous nitric solution resulting from the dissolution of the fuel in nitric acid, this step including at least one operation of coextracting the uranium and plutonium from said solution by a solvent phase; b) the partition of the coextracted uranium and plutonium to a first aqueous phase containing plutonium and uranium, and a second aqueous phase containing uranium but no plutonium; c) the purification of the plutonium and uranium that are present in the first aqueous phase; and d) a step of coconverting the plutonium and uranium to a mixed uranium/plutonium oxide. Applications: reprocessing of nuclear fuels based on uranium oxide or on mixed uranium-plutonium oxide.

Abstract: The invention relates to a method for separating uranium(VI) from one or more actinides selected from actinides(IV) and actinides(VI) other than uranium(VI), characterized in that it comprises the following steps: a) bringing an organic phase, which is immiscible with water and contains the said uranium and the said actinide or actinides, in contact with an aqueous acidic solution containing at least one lacunary heteropolyanion and, if the said actinide or at least one of the said actinides is an actinide(VI), a reducing agent capable of selectively reducing this actinide(VI); and b) separating the said organic phase from the said aqueous solution. Applications: reprocessing irradiated nuclear fuels, processing rare-earth, thorium and/or uranium ores.