Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Areva Nc

Commissariat a L'energie Atomique

Orano Cycle

Xavier Heres

Pascal Baron

Gilles Bernier

Manuel Miguirditchian

Christian Sorel

Laurence Chareyre

Marc Lemaire

Stéphane Pellet-Rostaing

Binh Dinh

Marinella Mazzanti

Michel Masson

Fabien Burdet

Alain Favre-Reguillon

Michael Lecomte

Julien Borrini

Elisabeth Zekri

Bernard Mauborgne

Marie-Thérèse Duchesne

Patrick Pochon

Danièle Sans

Clément Hill

Sylvain Costenoble

Vincent Vanel

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.

Use of hydroxyiminoalkanoic acids as anti-nitrous agents in operations of reductive stripping of plutonium

A method for the treatment of an aqueous solution resulting from the dissolution of a spent nuclear fuel in nitric acid, allowing the uranium and plutonium contained in the solution to be extracted, separated and decontaminated in a single cycle, without requiring any operation involving a reductive stripping of plutonium. Applications for the method include the processing of uranium-based and/or plutonium-based spent nuclear fuels.

Method for the treatment of an aqueous nitric solution resulting from dissolving spent nuclear fuel, said method being performed in a single cycle and without requiring any operation involving reductive stripping of plutonium

A method using diglycolamide for increasing the separation factor between americium and curium and/or between lanthanides during an extraction operation. The operation comprising putting an acid aqueous phase, in which are found the americium, curium and/or lanthanides, in contact with an organic phase non-miscible with water, containing at least one extractant in an organic diluent. The aqueous and organic phases are then separated, and the diglycolamide is added to the aqueous phase. This method can be used for processing and recycling irradiated nuclear fuels, in particular for selectively recovering americium from high activity aqueous solutions such as raffinates stemming from the processing of irradiated nuclear fuels with a PUREX or COEX&#x2122; method; processing of rare earth ores of the monazite, xenotime or bastnaesite type, in order to facilitate separation of &#x3c;&#x3c;lightweight&#x3e;&#x3e; rare earths from &#x3c;&#x3c;heavy&#x3e;&#x3e; rare earths and of yttrium, or that of two rare earths with adjacent or close atomic numbers.

Increase in the separation factor between americium and curium and/or between lanthanides in a liquid-liquid extraction operation

A process which allows separation of americium present in an acid aqueous phase or in an organic phase from the other metal elements also found in this phase, by complexation of the americium with a water-soluble ethylenediamine derivative; and a process for selective recovery of americium from an acid aqueous phase containing, in addition to americium, other metal elements, which comprises the application of this separation process.

Process for separating americium from other metallic elements present in an acidic aqueous or organic phase

A method with which americium may be selectively recovered from a nitric aqueous phase containing americium, curium and fission products including lanthanides and yttrium, but which is free of uranium, plutonium and neptunium or which only contains these three last elements in trace amounts. The method is applicable for treatment and recycling of irradiated nuclear fuels, in particular for removing americium from raffinates stemming from methods for extracting and purifying uranium and plutonium such as the PUREX and COEX&#x2122; methods.

Method for selectively recovering americium from a nitric aqueous phase

The invention relates to a process for collectively separating all the actinides (III), (IV), (V) and (VI) present in a strongly acidic aqueous phase, from the fission products, and in particular from the lanthanides, which are also present in this phase, using two extractants that operate in unconnected chemical fields. Applications: reprocessing of irradiated nuclear fuels, especially to recover plutonium, neptunium, americium, curium and, possibly, uranium present in trace amounts, in a grouped manner but selectively with respect to the lanthanides, from a solution for dissolution of an irradiated nuclear fuel, downstream of a uranium extraction cycle.

Grouped separation of actinides from a strongly acidic aqueous phase

The invention concerns a cyclic method for separating at least one chemical element Efrom at least one chemical element Efrom an aqueous solution containing said elements, which employs a mixture of two extractants operating in non-overlapping chemical fields. Each cycle of said method comprises: a) co-extracting elements Eand Eby means of an organic phase containing a first extractant suited to causing the migration of said elements into said organic phase; b) adding to the organic phase a second extractant suited to selectively retaining the element(s) Ein said organic phase during step c): c) selectively stripping the element(s) Efrom the organic phase; d) selectively stripping the element(s) Efrom the organic phase; e) separating the first and second extractants present in said organic phase at the end of step d).

Cyclic method for separating chemical elements present in an aqueous solution

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Avignon, France

Xavier Heres