Uranium hexafluoride properties

B) R. DeWitt, Uranium Hexafluoride A Survey of the Physico-Chemical Properties , GAT-280, Goodyear Atomic Corp, Portsmouth, Contract AT<33-2>1 (1960) C) L.S. Allen, A Parametric Survey of Criticality-Limited Fast Reactors Employing Uranium Fluoride Fuels , TR32-198, Jet Propulsion Lab, Contract NAS-7-100 (1962) D) C.A. Geffen et al, Assessment of the Risk of Transporting Uranium Hexafluoride by Truck and Train , Battelle, Richland, Contract EY-76-C-06-1830 (1978)... 

Uranium hexafluoride is probably the most interesting of the uranium fluorides. Under ordinary conditions, it is a dense, white solid with a vapor pressure of about 120 hull ai room temperature. It can readily be sublimed or distilled, and it is by far the most volatile uranium compound known. Despite its high molecular weight, gaseous UFg is almost a perfect gas, and many of the properties of the vapor can be predicted from kinetic theory. 

Property Uranium hexafluoride Uranium tetrachloride UranyF fluoride Uranyl acetate, dihvdrate Uranyl nitrate hexahvdrate... 

Beauchamp, J. L. "Properties and Reactions of Uranium Hexafluoride by Ion Cyclotron Resonance Spectroscopy,"... 

D3. DeWitt, R. Uranium Hexafluoride A Sumrrtary of the Physico-Chemical Properties, Report GAT-280, Aug. 12, 1960. 

Although the existence of a volatile higher fluoride of plutonium had been surmised from tracer experiments, positive evidence of the existence of PuF6 was obtained by Florin (31) who first prepared the compound. An investigation of the preparation and properties of PuF6 was also conducted by Mandleberg et al. (58). but in recent years the compound has been most intensively studied by Weinstock and his collaborators. Plutonium hexafluoride can be prepared by a variety of procedures similar to those used for the preparation of uranium hexafluoride. The most widely used method consists in the fluorination of plutonium tetrafluoride with elemental fluorine. Whereas uranium hexafluoride can be prepared by the analogous reaction at 300°, and neptunium hexafluoride at 500°, the preparation of plutonium hexafluoride by this reaction appears to require a... 

Prepare a tabulated report, using tabulated format, on the physical and chemical properties of the raw materials, intermediate products, by-products, and principal chemicals which will be encountered in the manufacture of (a) maleic anhydric hydrazide (fe) ethylene (r) uranium hexafluoride (solvent extraction (/) denatured alcohol from potatoes or any selected industrial chemical product. 

As it turned out, the properties of Teflon were ideal for an immediate and important application in the development of the first atomic bomb. Uranium hexafluoride (LIF5), which was used to separate fissionable by gaseous diffusion (see... 

Packages designed to contain uranium hexafluoride shall meet the requirements prescribed elsewhere in these Regulations which pertain to the radioactive and fissile properties of the material. Except as allowed in para. 632, uranium hexafluoride in quantities of 0.1 kg or more shall also be packaged and transported in accordance with the provisions of the International Organization for Standardization document ISO 7195 Packaging of Uranium Hexafluoride (UF ) for Transport [10], and the requirements of paras 630-631. 

Suppose you have a system you want to describe thermodynamically. How do you do it Perhaps most important in your description is what s in the system that is, the components of the system. For our purposes, a component is defined as a unique chemical substance that has definite properties. For example, a system composed of pure UFg has a single chemical component uranium hexafluoride. Granted, UFg is composed of two elements, uranium and fluorine, but each element lost its individual identity when the compound UFg was formed. The phrase chemically homogeneous can be used to describe single-component systems. 

A practical application of Graham s law arose during World War II, when scientists were studying the fission of uranium atoms as a source of energy. It became necessary to separate which is fissionable, from the more abundant isotope of uranium, which is not fissionable. Because the two isotopes have almost identical chemical properties, chemical separation was not feasible. Instead, an effusion process was worked out using uranium hexafluoride, UFs. This compound is a gas at room temperature and low pressures. Preliminary experiments indicated that could indeed be separated... 

Wagner W, Edelstein N, Whittaker B and Brown D 1977 Spectral properties of bis (tetraethy-lammonium) nraninm hexaiodide bis (tetraethylammonium) uranium hexafluoride. Inorganic Chemistry 16(5), 1021-1026. 

All the metals are very electropositive and attacked by water vapor with production of hydrogen. They are slowly oxidized in air and at higher temperatures in the form of small chips, they are pyrophoric. The oxides, nitrides, and halides are produced most easily by beating the metals in the appropriate elemental gas. The fluorides are among the most important solid actinide compounds since they are the starting material for the production of the metals. The volatile hexafluoride of uranium is used in isotopic ouichment (Ch. 2). The preparation and properties of U and Th is described in 5.4 — 5.5. Actinide chemistry is also discussed in 21.5 and 22.6. 

The transuranium elements such as neptunium, plutonium or americium form hexafluoride compounds at their highest valency state with physical properties close to those of UF6 but these compounds are not stable when the fluorine partial pressme decreases. Under such conditions they are converted into a lower valency state and remain as a soUd product. This means that the main fraction of these impurities can be collected as ash or dust if there is still a small proportion remaining in the liquid UFe, it can be removed by a special filter before the container is filled. The specified upper limit for residual transuranium activity in the reprocessed uranium amounts to 2.5Bq/gU, with Pu, Pu and Np as the guide isotopes. 

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