Compagnie Generale Des Matieres Nucleaires

Framatome Anp Gmbh

Cogema Compagnie Generale Des Matieres Nucleaires

Commissariat a L'energie Atomique

Universite Claude Bernard – Lyon1

Cnam-Conservatoire National Des Arts Et Metiers

Cogema Compagnie Generale Des Matieres Nuclearies

Cogema Compagnie General Des Matieres Nucleaires

Cogema-Compaignie Generale Des Matieres Nucleaires

Cogema-Compagnie Generale Des Matieres Nuclearires

Alain Guy

Jacques Foos

Marc Lemaire

Rodolph Chomel

Vincent Guyon

Rodolphe Chomel

Micheline Draye

Pierre Doutreluigne

Henri Le Roy

Stéphane Pellet-Rostaing

Frédéric Chitry

Pierre Doutreluingne

Olivier Vigneau

Andre Deloge

Thierry Moutarde

Gerard Le Buzit

Gerard Cauquil

Colette Bardot

Henri Barnier

Christel Gozzi

Alain Vian

Rene Chevillotte

Andre Delo Ge

Pierre Patigny

Bruno Leclere

Eric Gaubert

Jean-Jacques Radecky

Alain Maurel

Pierre Epherre

A process in which isotopes of the same element belonging to the alkaline earth metals, transition elements and heavy metals having an atomic mass of less than 209, in particular lanthanide metals, are separated in an aqueous medium by treating an aqueous medium.

Method of separating isotopes

The invention relates to the separation of lanthanides and actinides by nanofiltration complexation. The object of the invention is to satisfy the existing need for a simple, efficient and economical technique for separating lanthanides and actinides. This object is achieved by a process consisting of using ligands of the polyamino acid type, such as EDTA or DTPA, for complexing lanthanides and/or actinides before separating them by nanofiltration. The invention further relates to novel polyamino acid ligands incorporating ligand structures additional to EDTA and DTPA. Application to the production of rare earths or nuclear waste processing, especially to recycling operations carried out on spent nuclear fuels is also discussed.

Method for separating in an aqueous medium lanthanides and/or actinides by combined complexing-nanofiltration, and novel complexing agents therefor

The invention relates to a process for separating sodium from aqueous effluents resulting from the reprocessing of spent nuclear fuel elements. According to the invention, the effluent (3) is introduced into a tangential filtration module (11), whose membranes are made from polyaramide, sulphonated polysulphone or perfluorinated ionomer, so as to collect a permeate P containing sodium, depleted in radioactive elements and a retentate R enriched in radioactive elements.

Process for separating sodium from aqueous effluents resulting from the

Process and installation for the decontamination of radioactive nitric

The invention relates to a process fop trapping gaseous ruthenium on polyvinyl pyridine, more particularly usable for recovering radioactive ruthenium from irradiated nuclear fuels. This process consists of contacting a gas containing ruthenium in gaseous form with an adsorbent (11b) constituted by a vinyl pyridine polymer or copolymer for fixing the ruthenium to the latter. The gas can be constituted by yapours from a concentrate of fission products containing ruthenium, which has been heated (at 31) in the presence of an oxidizing agent for volatilizing the ruthenium.

Process for trapping gaseous ruthenium on polyvinyl pyridine, more

The invention relates to a process for the separation of at least one element such as Nb, Sb, Ce+Pr, actinides and elements from groups VIIb and VIII of the Periodic Classification of Elements from aqueous solutions resulting from the reprocessing of spent nuclear fuels. This process consists of contacting said aqueous solution with a solid resin based on a vinyl pyridine polymer or copolymer and separating from said solution the resin used for fixing said element or elements. The resin is in particular a poly(vinyl-4-pyridine) powder in crosslinked from and the separated elements are e.g. ruthenium, rhodium, palladium, technetium, manganese, cobalt, iron, nickel, cerium and praseodymium.

Process for the separation of certain elements from aqueous solutions

The invention concerns the recovery of Pu (IV) by using crown compounds. According to the invention, the aqueous solution containing the plutonium (IV) is placed in contact with at least one crown compound, for example DCH 18C6, dissolved in an organic diluting agent, such as benzonitrile. In the case where the solution only contains traces of Pu, it is possible to use a crown compound secured to a solid phase, such as silica. The aqueous solution is a concentrated solution of fission products, an effluent originating from an irradiated nuclear fuel reprocessing installation or a concentrated solution of plutonium with americium.

Method for recovering with the aid of a crown compound plutonium (IV)

The invention relates to the use of thioether ligands in accordance with the formula: ##STR1## in which R.sup.1 and R.sup.2, which can be the same or different, represent alkyl radicals, R.sup.3 is an alkyl radical and A represents a divalent radical chosen from among the radicals of formula:

Use of thioether ligands for separating palladium from aqueous solutions

A method for separating plutonium from uranium and from fission products with the aid of crown ether compounds comprising contacting an aqueous solution A0 containing Pu, U and fission products with an organic solvent O0 containing at least one crown ether compound to obtain an organic solution O1 containing Pu and U; extracting U from the organic solution O1 with an aqueous solution A4 such as water or nitric acid to obtain an aqueous solution A5 containing U and an organic solution O3 containing mainly of Pu and recovering Pu from the organic solution using an aqueous solution A6 such as sulfuric acid.

Method for separating by using crown compounds plutonium from uranium

A method for separating the isomers of a crown ether compound and making it possible to recover in particular the pure cis-syn-cis isomer from DCH 18C6 includes:

Method of separating isomers of a crown ether compound to recover

Process for separating plutonium from uranium contained in a nitric acid aqueous solution from the reprocessing of irradiated fuels comprising plutonium, uranium and fission products by means of crown ethers. Nitric acid aqueous solution (5) containing plutonium, uranium and fission products is contacted at (2) with an organic liquid membrane (3) containing a crown ether. The uranium and plutonium are extracted in the liquid membrane (3) and then transferred by said membrane into a receiving solution (7), which becomes enriched with uranium, because the latter is transferred more rapidly than the plutonium. The crown ether can be DCH 18 C6 or DB 18 C6.

Process for separating by means of crown ethers the uranium and

Growing community of inventors

Pontcarre, France

Alain Guy