Abstract: Method and apparatus for separating isotopes in an isotopic mixture of atoms or molecules by increasing the mass differential among isotopic species. The mixture containing a particular isotope is selectively irradiated so as to selectively excite the isotope. This preferentially excited species is then reacted rapidly with an additional preselected radiation, an electron or another chemical species so as to form a product containing the specific isotope, but having a mass different than the original species initially containing the particular isotope. The product and the remaining balance of the mixture is then caused to flow through a device which separates the product from the mixture based upon the increased mass differential.

Abstract: A process for recovering uranium from a wet-process phosphoric acid crude solution is provided in which the phosphoric acid crude solution is contacted with an organic extractant consisting of octylphenyl phosphoric acid, di(2-ethylhexyl)phosphoric acid and trioctylphosphine oxide dissolved in an organic diluent to extract uranium from the phosphoric acid crude solution. The thus uranium loaded organic extractant is then contacted with mixed acid consisting of hydrofluoric acid and sulfuric acid, or alternatively with concentrated phosphoric acid to back-extract the uranium from the organic extractant.

Abstract: Irradiated nuclear fuels consisting primarily of plutonium compounds and/or uranium compounds such as oxides, carbides, nitrides are converted in accordance with the method to plutonium hexafluoride and/or uranium hexafluoride. In a first step, the compounds are contacted within a first zone of an enclosure with a gas mixture containing at least one fluorination reagent. In a second step, the remainder of the compounds which have not been converted to fluorides during the first step is contacted directly within a second zone of the enclosure with a bed which has been fluidized by means of a gas mixture containing at least one fluorination reagent.

Abstract: Compositions of matter are described comprising the intercalation of Lewis bases into the layer lattice structure of UO.sub.2 F.sub.2 or by formation of directed chemical bonds between an electron donor atom of the Lewis base and the uranium ions in UO.sub.2 F.sub.2. Thermal treatment of these compositions results in the release of the Lewis base unchanged and the recovery of the uranyl fluoride.

Abstract: A process for increasing the average reaction rate of reduction of UO.sub.2 F.sub.2. The UO.sub.2 F.sub.2 is treated with an organic compound which interacts with the UO.sub.2 F.sub.2. The combination is decomposed to yield UO.sub.2 F.sub.2 in a kinetically reactive state.

Abstract: This invention relates to a novel method and a novel generator, or source, for providing gaseous negative ions of selected metal hexafluorides. The method is summarized as follows: in an evacuated zone, reacting gaseous fluorine with an actinide-metal body selected from the group consisting of uranium, plutonium, neptunium, and americium to convert at least part of the metal to the hexafluoride state, thus producing gaseous negatively charged metal-hexafluoride ions in the evacuated zone, and applying an electric field to the zone to remove the ions therefrom. The ion source comprises a chamber defining a reaction zone; means for evacuating the zone; an actinide-metal body in the zone, the metal being uranium, plutonium, neptunium, or americium; means for contacting the body with gaseous fluorine to convert at least a part thereof to the hexafluoride state; and means for applying an electric field to the evacuated zone to extract gaseous, negatively charged metal-hexafluoride ions therefrom.

Abstract: A method is disclosed for the selective separation and sequestering of plutonium from uranium which comprises contacting a gas stream containing uranium hexafluoride [at a partial pressure of 26 torr or less] and plutonium hexafluoride at any pressure with graphite whereby PuF.sub.6 is selectively intercalated into the graphite while UF.sub.6 is left unreacted in the gas stream. Preferably, the contacting of UF.sub.6 and PuF.sub.6 with graphite is conducted in the presence of excess fluorine.In another embodiment the graphite is first reacted with a chemical oxidant. Such pretreatment of the graphite renders it inert to UF.sub.6 intercalation at partial pressures over 26 torr, the pressure above which UF.sub.6 normally intercalates with graphite. Such pretreatment will have less effect on PuF.sub.6 intercalation into the prereacted graphite compound and therefore will permit the separation of UF.sub.6 -PuF.sub.

Abstract: A continuous, four stage fluidized bed process for converting uranium hexafluoride (UF.sub.6) to ceramic-grade uranium dioxide (UO.sub.2) powder suitable for use in the manufacture of fuel pellets for nuclear reactors is disclosed. The process comprises the steps of first reacting UF.sub.6 with steam in a first fluidized bed, preferably at about 550.degree. C, to form solid intermediate reaction products UO.sub.2 F.sub.2, U.sub.3 O.sub.8 and an off-gas including hydrogen fluoride (HF). The solid intermediate reaction products are conveyed to a second fluidized bed reactor at which the mol fraction of HF is controlled at low levels in order to prevent the formation of uranium tetrafluoride (UF.sub.4). The first intermediate reaction products are reacted in the second fluidized bed with steam and hydrogen at a temperature of about 630.degree. C. The second intermediate reaction product including uranium dioxide (UO.sub.

Abstract: A process for preparing anhydrous metal fluorides is described wherein metal is reacted with HF and halogen in the presence of a nitrile.

Abstract: A method for separating specific isotopes present in an isotopic mixture by aerodynamically accelerating a gaseous compound to form a jet of molecules, and passing the jet through a stream of electron donor atoms whereby an electron transfer takes place, thus forming negative ions of the molecules. The molecular ions are then passed through a radiofrequency quadrupole mass filter to separate the specific isotopes. This method may be used for any compounds having a sufficiently high electron affinity to permit negative ion formation, and is especially useful for the separation of plutonium and uranium isotopes.

Abstract: A three stage fluidized bed process for converting uranium hexafluoride (UF.sub.6) to a ceramic-grade uranium dioxide (UO.sub.2) powder by first, reacting hydrogen and steam with UF.sub.6 in a first fluidized bed in a temperature range of from about 475.degree. to 600.degree. C to form solid intermediate products UO.sub.2 F.sub.2 and U.sub.3 O.sub.8 ; second, reacting hydrogen and steam with the intermediate products in a second fluidized bed at a temperature ranging from about 575.degree. to about 675.degree. C to produce a second group of intermediate products including UO.sub.2 F.sub.2, U.sub.3 O.sub.8, and UO.sub.2 ; and, third, reacting hydrogen and steam with the second group of intermediate products in a third fluidized bed at a temperature of 575.degree. to 675.degree. C to produce ceramic grade UO.sub.2 powder having low residual content of fluorides and other foreign materials.

Abstract: A compound of a chemical element to be isotopically enriched is placed in a working zone with an auxiliary material and temperature and pressure conditions are controlled to cause a liquid solution to occur. The liquid solution is injected through a nozzle into a separating chamber, for example, at substantially constant pressure and with slight elevation of temperature, to cause a phase change, the liquid solution yielding a solid phase which is enriched in respect of an isotope of the chemical element and a gaseous phase which is depleted. The series of such stages are arranged in cascade with the enriched solid phase being passed forward to the following stage for further enrichment and the depleted gaseous phase being passed back to the previous stage for further depletion. The arrangement is especially applicable to uranium enrichment, wherein the compound is uranium hexafluoride and the auxiliary material is tungsten hexafluoride.

Abstract: A novel method is disclosed for producing a pure uranium trifluoride efficiently. Said method is characterized by heating a mixture of uranium tetrafluoride and uranium nitride in an inert gas stream or under vacuum.

Abstract: Uranium dioxide powder is prepared by the AUC (ammonium uranyl carbonate) method. Supplementing the known process steps, the AUC, after separation from the mother liquor, is washed with an ammonium hydrogen cabonate or an NH.sub.4 OH solution and is subsequently post-treated with a liquid which reduces the surface tension of the residual water in an AUC. Such a liquid is, for instance, alcohol.

Abstract: A process which comprises reacting at a temperature above 100.degree.C. a metal oxide, hydroxide or a mixture thereof with aqueous fluosilicic acid, said fluosilicic acid having a concentration of about 10 to 45% by weight, to form gaseous silicon tetrafluoride and the corresponding metal fluoride and recovering said metal fluoride from the reaction medium.

Abstract: A method of recovering uranium hexafluoride from gaseous mixtures employing as an absorbent a liquid composition at least one of the components of which is chosen from the group consisting of ethanolamine, diethanolamine, and 3-methyl-3-amino-propane-diol-1,2.

Abstract: The production of UF.sub.6 in which UF.sub.4 is reacted with air or oxygen in the presence of a catalyst at 500.degree. to 700.degree.C. The solid byproduct of this reaction is reduced with hydrogen in the presence of a catalyst at 400.degree. to 600.degree.C. Fresh UO.sub.3 may also be reduced with hydrogen in the same reactor as UO.sub.2 F.sub.2. The reduction product or products are reacted with hydrogen fluoride at 400.degree. to 600.degree.C, producing UF.sub.4 which would be recycled for further reaction to produce UF.sub.6.