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A Glass Still for the Evaluation of Column Packing With Uranium Hexafluoride

Description: The operating holdup and flooding rates of uranium hexafluoride, n-heptane, and perfluorodimethylcyclohexane have been studied in a glass still filled with 1/8 inch nickel Heli-Pak. The flooding rates of the latter two substances are 46.0 and 48.0 cc./min. respectively and the flooding rate for uranium hexafluoride, calculated from the Bertetti equation, is 42.9 cc./min. The operating holdups for these three substances on Heli-Pak were measured at several throughput rates up to the flooding rate and an equation derived, based on the method of Jesser and Elgin, for computing the holdup of uranium hexafluoride from a knowledge of the holdup of perfluorodimethylcyclohexane. Observations of the performance of the packing and a measurement of the number of drops of uranium hexafluoride per milliliter at 75 deg C. are also presented.
Date: July 1, 1951
Creator: McGill, R. M.
Partner: UNT Libraries Government Documents Department

Critical Ionization of Potentials of Uranium Hexafluoride

Description: Introduction: "The extensive use of uranium hexafluoride in the Nier-type mass spectrometers, where the ionization is produced by slow electrons, made a knowledge of the ionization potentials of the various ions desirable. This information was not available and work was accordingly begun to secure such data. The first measurement was made with a VGIA ion gauge and has been described in TEO report CD-310. With this apparatus it was not possible to identify the ionization products and it was presumed that the value reported was for the UF5 ion. When time and equipment became available, the work was continued and the critical potentials of the singly-charged ions determined."
Date: November 28, 1955
Creator: Cameron, Angus Ewan, 1906- & White, J. R.
Partner: UNT Libraries Government Documents Department


Description: Thermodynamic considerations indicate that sodium should be favorable for the one-step reduction of UF/sub 6/ to uranium metal. A reaction vessel was developed for the continuous reduction of UF/sub 6/ to metal with batch collection of the products, and several experimental tests established the chemical feasibility of this direct and continuous reduction. Up to 93.5% of the uranium content of UF/sub 6/ continuously reduced by sodium in a reaction vessel was recovered as massive uranium metal in the form of a metal button of acceptable purity. A remaining problem is development of compatible materials of construction. (auth)
Date: April 1, 1963
Creator: Scott, C.D.
Partner: UNT Libraries Government Documents Department

Gas Titration Methods for Uranium Hexafluoride

Description: This report studies the reactions between gaseous uranium hexafluoride and several gaseous reagents for possible analytical application that has been underway while using a buggy designed for gaseous titration studies. This study primarily focuses on methods to analyze gases containing uranium hexafluoride and physically absorbed uranium hexafluoride.
Date: December 2, 1953
Creator: Weber, C. W.
Partner: UNT Libraries Government Documents Department

The Preparation and Some Properties of a Uranium Hexafluoride-Sodium Fluoride Complex

Description: Report discussing "preparation of some stable complexes of uranium hexafluoride with sodium, potassium, and thallium fluorides...Such compounds, reported as stable in air and of low vapor pressure, offered promise as convenient sources of unoxygenated hexa-valent uranium without the difficulties associated with the use of uranium hexafluoride itself."
Date: November 30, 1950
Creator: Horton, Charles A.; Harris, Warren W.; Barr, John T. & Posey, J. C.
Partner: UNT Libraries Government Documents Department


Description: Tables of temperature dependent coefficients are presented for the computation of thermodynamic properties of gaseous UF/sub 6/ using equations which express the properties as expansions in powers of pressure. The various coefficients listed were computed in one degree increments for a temperature range of 500 to 999 deg R. This set of tables was computed by use of a virial equation representation for the equation of state and the thermodynamic properties were derived from this representation. (auth)
Date: September 30, 1960
Creator: Parks, B.H. & Burton, D.W.
Partner: UNT Libraries Government Documents Department

Releases of UF{sub 6} to the atmosphere after a potential fire in a cylinder storage yard

Description: Uranium hexafluoride (UF{sub 6}), a toxic material, is stored in just over 6200 cylinders at the K-25 site in Oak Ridge, Tennessee. The safety analysis report (SAR) for cylinder yard storage operations at the plant required the development of accident scenarios for the potential release of UF{sub 6} to the atmosphere. In accordance with DOE standards and guidance, the general approach taken in this SAR was to examine the functions and contents of the cylinder storage yards to determine whether safety-significant hazards were present for workers in the immediate vicinity, workers on-site, the general public off-site, or the environment. and to evaluate the significance of any hazards that were found. A detailed accident analysis was performed to determine a set of limiting accidents that have potential for off-site consequences. One of the limiting accidents identified in the SAR was the rupture of a cylinder engulfed in a fire.
Date: June 1, 1997
Creator: Lombardi, D.A.; Williams, W.R. & Anderson, J.C.
Partner: UNT Libraries Government Documents Department

Depleted uranium storage and disposal trade study: Summary report

Description: The objectives of this study were to: identify the most desirable forms for conversion of depleted uranium hexafluoride (DUF6) for extended storage, identify the most desirable forms for conversion of DUF6 for disposal, evaluate the comparative costs for extended storage or disposal of the various forms, review benefits of the proposed plasma conversion process, estimate simplified life-cycle costs (LCCs) for five scenarios that entail either disposal or beneficial reuse, and determine whether an overall optimal form for conversion of DUF6 can be selected given current uncertainty about the endpoints (specific disposal site/technology or reuse options).
Date: February 1, 2000
Creator: Hightower, J.R. & Trabalka, J.R.
Partner: UNT Libraries Government Documents Department


Description: The chemical feasibility of the direct, continuous reduction of UF/sub 6/ to U with Na was shown in several tests. Up to 93.5% of the U content of UF/sub 6/ continuously reduced by Na in a reaction vessel was recovered as massive U metal of acceptable purity. A semicontinuous reactor for continuous reduction is described. (D.L.C.)
Date: May 24, 1961
Creator: Scott, C.D.
Partner: UNT Libraries Government Documents Department


Description: After two batches ( approximately 340 kg) of fluoride salt from the ARE were reprocessed, a pilot plant operations were terminated because of a leak through which an estimated 780 g of uranium (as UF/sub 6/ escaped. Of the 21 kg of highly enriched uranium in the feed, 93.12% was collected as UF/sub 6/ product, 0.13% represented measured losses, and 3.72% was unaccounted for (leak). An additional 3.03% was reclaimed from NaF beds and equipment washes. The produce met both chemical purity and activity specifications for product level UF/ sub 6/. Decontamination from fission products was essentially complete. A gross gamma decontamination factor was apparently limited by the low activity of the feed salt. (auth)
Date: May 11, 1959
Creator: Whitmarsh, C.L.
Partner: UNT Libraries Government Documents Department


Description: Ore concentrates were converted directly to crude uranium tetrafluoride by hydrogen reduction aad hydrofluorination in fluidized-bed reactors. Small- scale laboratory experiments demonstrated that this process can be extended to the production of crude uranium hexafluoride through fluorination of the uranium tetrafluoride in a fluidized bed. The satisfactory temperature range for the reaction lies between 300 and 600 deg C. At 450 deg C the fluorine utilization is between 50 and 80%. With excess fluorine, over 99% of the uranium is volatilized from the solid material. The fluidization characteristics of certain materials are improved by the addition of an inert solid diluent to the bed. (auth) .
Date: December 1, 1957
Creator: Sandus, O. & Steunenberg, R.K.
Partner: UNT Libraries Government Documents Department


Description: Experiments were carried out to determine the extent and rate of separation of mixtures of uranium hexafluoride and plutonium hexafluoride by selective thermal decomposition. Gaseous mixtures of uranium hexafluoride, plutonium hexafluoride, and helium were circulated for varying lengths of time through nickel vessels packed with nickel wool at temperatures of 150, 200, and 300 deg C. The initial ratios of uranium hexafluoride to plutonium hexafluoride in the mixtures were of the order of 10 to 1. The gas phase was analyzed for uranium and plutonium before and after circulation. The amounts of uranium and plutonium in the solid compounds deposited in the vessels were also determined. Passage of the mixtures through the hot vessels resulted in the removal of 99.5 to 99.9% of the plutonium. The solid product remaining in the vessels was plutonium tetrafluoride containing 0.09 to 1.3% uranium. The separation of plutonium hexafluoride from uranium hexafluoride by selective thermal decomposition is applicable to fluid bed fluoride volatility processes for the recovery of fissile material from reactor fuels. (auth)
Date: August 1, 1963
Creator: Trevorrow, L.; Fischer, J. & Riha, J.
Partner: UNT Libraries Government Documents Department