- Influence of molten salt composition on the fluorination of UF4
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The fluorination of UF4 by F2 in LiF-NaF-KF(46.5-11.5-42 mol%, FLiNaK), FLiNaK-ThF4(88.0–12.0 mol.%) and KF-ZrF4(58–42 mol%, FKZr) at 550 °C was investigated, and the results indicated the conversion rate of UF4 to UF6 was different in FLiNaK with the other two molten salts. Raman spectroscopy and X-ray diffraction (XRD) were used to study the influence of the fluoroacidity on the coordination structure of Zr (IV) and U(IV) in FLiNaK with various contents of ZrF4. The results indicated that the concentration of free F? decreased and the molten salt became more acidic with the increase of ZrF4 content. The main Zr(IV) complex present changed from ZrF73?, ZrF62? to ZrF5? as the U(IV) complex changed from UF84? or UF73? to UF62?. The fluorination of UF4 in FLiNaK with various fluoroacidity suggested that a higher fluoroacidity of molten salts resulted in relatively low coordination numbers of Zr-F and U-F, a higher conversion rate and average reaction rate of UF4 to UF6, and less corrosive of the structural material.
- Sun, Lixin,Niu, Yongsheng,Hu, Congwei,Wang, Chenyang,Dou, Qiang,Li, Qingnuan
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- Study on the fluorination reaction of uranium tetrafluoride by nitrogen trifluoride
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The fluorination of UF4 by NF3 at different temperatures was investigated using in-line Fourier transform infrared (FTIR) spectroscopy. The results indicated that the fluorination between NF3 and UF4 occurred only when the temperature was above 723 K, and the temperature had a significant effect on the average reaction rate and the utilization rate of NF3. The in-line FTIR spectrum analysis and thermodynamic calculation indicated that UF4 was converted to UF6 with the following reaction mechanism: 2/3NF3(g) + UF4(s) = UF6(g) + 1/3N2(g). The conversion rate of UF4 to UF6 increased from 1.53 to 2.68 gU h?1 and the utilization rate of NF3 increased from 10.5%–22.5 % when the reaction temperature increased from 723 K to 873 K. The calculated rate constant increased from 1.6 × 10?2 to 3.1 × 10?2 min?1 in the range of 723 K to 873 K, and the activation energy of the reaction was 22.56 kJ/mol.
- Niu, Yongsheng,Sun, Lixin,Hu, Congwei,Zhou, Jinhao,Dou, Qiang,Li, Qingnuan
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- Structural study and properties of the alkali metal, nitrosyl, and ammonium hepta- and octafluorouranates(VI)
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The thermal decomposition of the heptafluorouranates(VI) of the alkali metals is shown to take place in two steps. The first step gives the octafluorouranates(VI) and UF6, and the decomposition rate is noticeable at temperatures above 100, 130, 150, and 210°C for the Na, K, Rb, and Cs salts, respectively. The second step for Na2UF8 yields pure NaF and UF6 above 300°C, whereas the decomposition temperatures for the K, Rb, and Cs salts are above 300, 350, and 400°C, respectively. Depending on the decomposition conditions, F2 and M2UF7 (M = K, Rb, Cs) or F2, UF6, and M3UF8 are formed. The heptafluorouranates(VI) of all the cations studied, except for ammonium, were shown to exhibit dimorphism. The parameters of their cubic form were obtained and are as follows: KUF7; a = 5.22 A?; RbUF7; a = 5.385 A?; CsUF7; a = 5.517 A?; NOUF7; a = 5.334 A?; NH4UF7; a = 5.393 A?; NaUF7(fccub), a = 8.511 A?, Z = 4. The x-ray pattern of the low-symmetry form of CsUF7 just below the solid transition temperature (15 ± 1°C) was indexed with a tetragonal cell where a = 5.50 A? and c = 5.37 A?. The x-ray diagrams of the low symmetry form of the other MUF7 salts were not indexed, whereas those of the octafluorouranates were indexed with orthorhombic cells. The vibrational spectra of the hepta- and octafluorouranates were found to be very dependent on the temperature, and for the same temperature on the cation size. In the solids at high temperature the disordered F positions are likely to be averaged to give pseudo-D5h and Oh symmetry structures for the UF7- and UF82- ions, respectively. At lower temperature, as the motions are frozen out, the observed spectra for the hepta- and octafluorouranates arise from structures of symmetry no higher than C2ν and D2d, respectively. The ions UF7- and UF82- were characterized in nitrosyl or cesium fluoride HF solutions, which were found to exchange F- ions with these anions. Based on observation of the chemical exchange between UF6 and UF7- and on a comparative study of the WF7- ion, a fluoride ion transfer mechanism is also found for UF7- dissolved in acetonitrile. Some trends observed in this study, like the thermal decomposition temperatures or the relative symmetries, are thought to arise from the differences in the cation-anion interaction. This interaction is stronger with smaller cations, which results in more distorted anions, less ionic U-F bonds, and paradoxically less stable complexes.
- Bougon,Charpin,Desmoulin,Malm
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- Thermogravimetric study of the reaction of uranium oxides with fluorine
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Thermogravimetric study of the reaction of uranium oxides with fluorine was conducted by TG-DTA method using anti-corrosion type differential thermobalance. When UO2 was heated from R.T. to 500 °C in 5% F2/He atmosphere, the weight increase appeared at ca. 250 °C with an exothermic peak. Then the weight decreased slightly with a small exothermic peak followed by the complete volatilization with a large exothermic peak at ca. 350 °C. At a flow rate of 15, 30, 60 ml min-1, there seemed to be no significant change for the fluorination of UO2. With the different heating rates of 1, 2, 5 and 10 °C min-1, the fluorination peak shifted to higher temperature with increasing heating rates. For the comparison with thermogravimetric results, phase analysis by XRD method was conducted for the products obtained at different temperatures. At 260 °C, the product was UO2 with a small amount of the intermediate compound, UO2F. The amount of this compound increased with increasing temperature up to 320 °C. Then another phase of UO2F2 appeared at 340 °C but it was immediately fluorinated to the volatile fluoride. When U3O8 was used as a starting material, it was found that the steep weight decrease peak appeared at ca. 350 °C and the uranium volatilized completely. This result suggests that fluorination of U3O8 occurs at this temperature forming UF6. Uranium trioxide showed the similar fluorination behavior to that of U3O8.
- Komura, Motohiro,Sato, Nobuaki,Kirishima, Akira,Tochiyama, Osamu
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- Reaction of Fluorine Atoms with Monomeric and Polymeric Uranium Pentafluoride
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We have measured the room-temperature rate constants for formation of UF6 from the reaction of fluorine atoms with UF5.The rapid growth of UF5 clusters (polymers) from the nascent monomeric species complicates the rate measurements.The ratio of the rate of UF5-dimer formation to the rate of monomer-fluorine recombination is insensitive to the cluster formation.The ratio, kmm/krm = 5.0 +/- 1.0, is our most reliable experimental result.It, along with additional experimental data, gives krm = 8.0 x 1E-12 cm3 molecule-1 s-1 and kmm = 4.0 x 1E-11 cm3 molecule-1 s-1.To obtain the dependence of reaction rates on s, the average UF5 polymer size, we assumed that the rates were proportional to the collision rate.The derived rate constants were kpp = kmms1/6 cm3 molecule-1 s-1 for cluster growth and krp = 4.1 x 1E-14(1 + 2s1/3)2 cm3 molecule-1 s-1 for reaction of fluorine atoms with polymeric UF5.The experimental procedure was to photolyze both F2 and UF6 in helium diluent with a KrF excimer laser to produce UF5 and an excess of fluorine atoms.This allowed the slower recombination reactions to compete with polymerization.We monitored the transient concentration of UF6 with an ultraviolet probe beam at 215 nm.The recombination of fluorine atoms with UF5 monomer is substantially faster than recombination with the polymer.
- Lyman, John L.,Holland, Redus
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- Preparation of MF6·NaF complexes with uranium, tungsten, and molybdenum hexafluorides
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The hexafluorides of uranium, tungsten, and molybdenum react with sodium fluoride to reach 1:2 and 1:1 stoichiometric ratios with unexpected speed when the sodium fluoride has been formed by decomposition of UF6·2NaF. The equilibrium pressures
- Katz, Sidney
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- Use of high-surface-area sodium fluoride to prepare MF6·2NaF complexes with uranium, tungsten, and molybdenum hexafluorides
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Successful preparation of MF6·2NaF compounds by gas-solid reactions is shown to be dependent on the use of high-surface-area sodium fluoride and proper reaction temperatures. The reaction was fastest with UF6 and proceeded most close
- Katz, Sidney
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- Darstellung and Characterisierung der kationischen Metallocen-Komplexe 2 und : Laborsynthese von UF6
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The five-coordinate, dicationic complex 2 (1) was formed by reaction of Cp2ZrCl2 and 2 equiv. of AgAsF6 in acetonitrile.A stable, polymeric niobocenium UF6 complex, (2), was synthesized from Cp2NbCl2 and UF6.A convenient laboraotry-scale synthesis of pure UF6 is reported.
- Schulz, Axel,Klapoetke, Thomas M.
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Read Online
- Plasmachemical synthesis of the binary hexafluorides of Mo, Os, Ir, Te, and U
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Starting from the respective metal, we have synthesized the binary hexafluorides MF6 of M = Mo, Os, Ir, Te, and U by the use of a remote fluorine plasma source using a mixture of Ar and NF3 as the feed gas. The formation of the binary hexafluorides was confirmed by several different spectroscopic methods including IR, Raman, UV/VIS, and NMR spectroscopy.
- Buchner, M. R.,Chemnitz, T.,Kraus, F.,Petry, W.
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- Separation of metallic residues from the dissolution of a high-burnup BWR fuel using nitrogen trifluoride
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Nitrogen trifluoride (NF3) was used to fluorinate the metallic residue from the dissolution of a high burnup, boiling water reactor fuel (~70 MWd/kgU). The washed residue included the noble-metal phase (containing ruthenium, rhodium, palladium, technetium, and molybdenum), smaller amounts of zirconium, selenium, tellurium, and silver, along with trace quantities of plutonium, uranium, cesium, cobalt, europium, and americium, likely as their oxides. Exposing the noble metal phase to 10% NF3 in argon, between 400 and 550 °C, removed molybdenum and technetium near 400 °C as their volatile fluorides, and ruthenium near 500 °C as its volatile fluoride. The events were thermally and temporally distinct and the conditions specified provide a recipe to separate these transition metals from each other and from the nonvolatile residue. Depletion of the volatile fluorides resulted in substantial exothermicity. Thermal excursion behavior was recorded with the thermal gravimetric instrument operated in a non-adiabatic, isothermal mode; conditions that typically minimize heat release. Physical characterization of the noble-metal phase and its thermal behavior are consistent with high kinetic velocity reactions encouraged by the nanoparticulate phase or perhaps catalytic influences of the mixed platinum metals with nearly pure phase structure. Post-fluorination, only two products were present in the residual nonvolatile fraction. These were identified as a nano-crystalline, metallic palladium cubic phase and a hexagonal rhodium trifluoride (RhF3) phase. The two phases were distinct as the sub-μm crystallites of metallic palladium were in contrast to the RhF3 phase, which grew from the parent, nano-crystalline noble-metal phase during fluorination, to acicular crystals exceeding 20-μm in length.
- McNamara, Bruce K.,Buck, Edgar C.,Soderquist, Chuck Z.,Smith, Frances N.,Mausolf, Edward J.,Scheele, Randall D.
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supporting information
p. 1 - 8
(2014/05/06)
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- Formation and characterization of HUF and DUF in solid argon
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Reactions of laser-ablated U atoms with HF and DF in condensing and solid rare gas produce HUF and DUF as the major new products based on close agreement between observed and calculated vibrational frequencies and deuterium shifts for U-H and U-F stretchi
- Vent-Schmidt, Thomas,Hunt, Rodney Dale,Andrews, Lester,Riedel, Sebastian
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p. 3863 - 3865
(2013/07/25)
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- Simple N≡UF3 and P≡UF3 molecules with triple bonds to uranium
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UN-beatable? Laser-ablated uranium atoms activate NF3 and PF3 to form the N≡UF3 and P≡UF3 molecules containing novel terminal nitride and phosphide functional groups. These molecules are identified from matrix infrared spectra and theoretical methods. The N≡UF3 molecule contains the strongest triple bond to uranium in a ternary compound.
- Andrews, Lester,Wang, Xuefeng,Lindh, Roland,Roos, Bjoern O.,Marsden, Colin J.
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p. 5366 - 5370
(2009/03/12)
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- Separation and recovery study of uranium from spent NaF (fillers)
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The molten salt technique is considered to be a feasible technique applicable for the removal of uranium from the spent NaF (fillers). Simple spent NaF or NaF with NaCl, i.e. mixed salt, was used as an electrolyte and the uranium concentrations in the bath, pre-treatment condition, electrolytic temperature, current density, etc. were given as parameters in this experiment. Results from the fundamental experiments showed the potential applicability of the molten salt technique for the removal of uranium from spent NaF.
- Amamoto, Ippei,Terai, Takayuki,Oobayashi, Hiroshi,Fujita, Reiko
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p. 602 - 607
(2008/10/09)
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- Matrix IR spectra of the products from F2, ClF, and Cl2 reactions with pulsed-laser evaporated uranium atoms
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Pulsed Nd:YAG laser ablated uranium atoms were codeposited with F2 and excess Ar onto a CsI window at 12 K. Infrared spectra revealed the presence of several uranium fluorides including the previously characterized UF4, UF5, and UF6. Lower laser energy favored new absorptions at 400, 446, 496, and 561 cm-1. These product absorptions increased stepwise during annealings which permitted diffusion and reaction of the fluorine. Similar studies with ClF produced the above absorptions plus a new band at 554 cm-1 which is tentatively assigned to ClF2-. The first bands appearing at 400 and 446 cm-1 are assigned to UF and UF2, respectively. The 496- and 561-cm-1 bands are tentatively assigned to UF3 and F3-, respectively. Finally, uranium atoms were reacted with Cl2. In addition to several absorptions due to UCl4, a new doublet at 312 and 308 cm-1 is assigned to UCl2.
- Hunt, Rodney D.,Thompson, Craig,Hassanzadeh, Parviz,Andrews, Lester
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p. 388 - 391
(2008/10/08)
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- Rate of reaction of uranium tetrafluoride with iodine heptafluoride
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An investigation has been made by IR spectroscopy of the rate of reaction of uranium tetrafluoride with iodine heptafluoride in a stream. The reaction rate constant, the orders of the reaction in the gaseous components, and the activation energy of the reaction have been determined.
- Pokidysheva,Prusakov,Timakov
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p. 177 - 179
(2008/10/08)
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- Preparation and Characterization of U2O2F7
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Reaction of UO2F2 with UF5 at 400 deg C under UF6-pressure of 3 atm followed by evaporation of excess UF5 has yielded a greenish white residue.Its X-ray diffraction pattern and infrared spectrum are sufficiently unique to establish that this material is a true compound.Its chemical formula has been shown to be U2O2F7, on the grounds of chemical analysis and thermal decomposition.The oxygen content was determined directly by means of 18O isotopic dilution method based on the combustion of the samples with BrF5.
- Asada, Kameo,Ema, Keiko,Iwai, Takashi
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p. 3189 - 3194
(2007/10/02)
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- Formation of actinide hexafluorides at ambient temperatures with krypton difluoride
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A second low-temperature agent, krypton difluoride, for generating volatile plutonium hexafluoride is reported (dioxygen difluoride is the only other reported agent). Plutonium hexafluoride is formed at ambient or lower temperature by the treatment of various solid substrates with krypton difluoride. Volatilization of uranium and neptunium from solid substrates using gaseous krypton difluoride is also reported for the first time. The formation of actinide hexafluorides has been confirmed for the reaction of krypton difluoride in anhydrous HF with UO2 and with uranium and neptunium fluorides at ambient temperatures. Treatment of americium dioxide with krypton difluoride did not yield americium hexafluoride under the conditions studied.
- Asprey,Eller,Kinkead
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p. 670 - 672
(2008/10/08)
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- INTERACTION BETWEEN URANIUM PENTAFLUORIDE AND THE PENTAFLUORIDES OF VANADIUM, ARSENIC, NIOBIUM, TANTALUM, AND BISMUTH, AND THE TETRAFLUORIDE OF SULPHUR
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The interaction of UF5 with SF4, SF4O, and some Lewis-acid pentafluorides of various strengths has been studied.In anhydrous HF solutions, SF4 was shown to yield an adduct of composition 3UF5*SF4 in which both ionic and fluorine-bridged species are present.The pentafluorides of arsenic, tantalum, and niobium combine with UF5 to give adducts of composition 1.5 UF5*AsF5, UF5*2TaF5, and UF5*2NbF5, respectively.The arsenic derivative is stable at room temperature only under a pressure of AsF5, whereas the tantalum and niobium adducts decompose at higher temperature forming UF5*TaF5 and UF5*NbF5, respectively.Vibrational spectroscopic study of the pentafluoride adducts of UF5 has shown that they consist of covalent fluorine-bridged species.Uranium pentafluoride is fluorinated at room temperature by VF5 and by BiF5 in anhydrous HF.
- Holloway, John H.,Staunton, Garry M.,Rediess, Klaus,Bougon, Roland,Brown, David
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p. 2163 - 2166
(2007/10/02)
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- Preparation and Characterization of the Adduct Uranium Pentafluoride-Arsenic-Pentafluoride (1/1)
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The system UF5-AsF5, UF6-AsF5-UF4, and UF4-AsF5-F2 were studied using anhydrous HF as a solvent.In all cases a dark blue solution results from which blue crystals of composition UF5.AsF5 were isolated at temperatures lower than -30 deg C.At room temperature thermal decomposition of the adduct takes place giving AsF5 vapour, and a solid residue which was identified as β-UF5.
- Gantar, Darja,Frlec, Boris
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p. 2345 - 2346
(2007/10/02)
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- BEHAVIOR OF VOLATILE RADIOACTIVE IMPURITIES DURING FLUORINATION OF URANIUM-CONTAINING MATERIALS.
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Results are given of investigations of the behavior of microimpurities of plutonium and gamma-active isotopes of ruthenium, cerium, niobium, and zirconium during the fluorination of regenerated uranous uranic oxide, obtained from spent fuel elements. Reasons are considered for the incomplete volatilization into the gaseous phase of plutonium and the radionuclides. An explanation is also given for the deposition of these impurities during the various purification operations.
- Galkin,Khomyakov,Kharin
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p. 223 - 226
(2008/10/08)
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- INTERACTION BETWEEN URANIUM TETRAFLUORIDE OXIDE AND THE PENTAFLUORIDES OF ARSENIC, NIOBIUM, TANTALUM, AND BISMUTH
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No reaction occurs between UF4O and AsF5 but UF4O*3MF5 (M=Nb and Ta) and UF4O*2BiF5 have been obtained as yellow or orange solids by warming mixtures of UF4O with excess of the appropriate pentafluoride in anhydrous HF or by combination of the oxide tetrafluoride with excess of the pentafluoride as a melt.The solid adducts have been charcterized by their reaction stoicheiometries, chemical analyses, and vibrational spectra.Like UF4O*2SbF5, the adducts are fluorine bridged with some ionic character.The thermal decomposition of the adducts results in the production of uranyl species.
- Holloway, John H.,Laycock, David,Bougon, Roland
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p. 2303 - 2306
(2007/10/02)
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- Preparation and Characterization of the Uranyl Fluoride-Antimony Pentafluoride Adduct, UF2O2*4SbF5
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When UF4O*2SbF5 is treated with anhydrous hydrogen fluoride a slow reaction in solution takes place.Investigation of this reaction and those of UF4O-SbF5-HF solutions on standing have shown that, in both cases, UF6 and a new uranyl fluoride derivative, UF2O2*4SbF5, are produced.
- Holloway, John H.,Laycock, David,Bougon, Roland
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p. 1635 - 1636
(2007/10/02)
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- Acid properties of the oxytetrafluorides of molybdenum, tungsten, and uranium toward some inorganic fluoride ion donors
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The behavior of MoOF4, WOF4, and UOF4 has been studied in the presence of ion donors of various strength: FNO, ClOF3, ClF3, ClF5, and HF. For both MoOF4 and WOF4 in HF solutions, evidence for a partial ionization into Mo2O2F9- and W2O2F9- has been shown. From the equilibrium constant values, WOF4 is found to be a stronger Lewis acid than MoOF4, whereas no direct comparison with the strength of UOF4 is possible because of its quasiinsolubility in HF. Lewis acid properties of the oxytetrafluorides studied are also demonstrated by the ionic structures found for the adducts with the strong bases FNO and ClOF3. The new adducts NOMo2O2F9, NOW2O2F9, ClOF2Mo2O2F9, ClOF2MoOF5, (NO)2MoOF6, and (NO)2WOF6 were prepared. Their vibrational spectra and, for some of them, X-ray powder diffraction patterns are given. The unit cell parameters of the adducts NOMoOF5, NOWOF5, and (NO)2WOF6 have been determined. A study of the HF solutions of the nitrosyl salts has been made by Raman and 19F NMR spectroscopy. This, together with data on propylene carbonate solutions of the same adducts, allowed the identification of the species in the oxytetrafluoride-FNO-HF system. Depending on the F- concentration the anions M2O2F9-, MOF5-, and MOF62- (M = Mo or W) are formed, which are in equilibrium with the solvent. The mechanisms of these equilibria are proposed. The results obtained with the F- donor fluorinating agents indicate that ionic intermediary steps occur in the fluorination process of the oxytetrafluorides to the corresponding hexafluorides.
- Bougon,Huy, T. Bui,Charpin
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p. 1822 - 1830
(2008/10/08)
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- Synthesis, characterization, and structure of uranium oxide tetrafluoride
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The synthesis of uranium oxide tetrafluoride from the combination of uranium hexafluoride and quartz wool (SiO2) in anhydrous hydrogen fluoride solution is reported. The slow reaction 4HF + SiO2 → SiF4 + 2H2O provides a stoichiometric, one-step, controlled, partial hydrolysis of UF6. The characterization of UOF4 including electronic and vibrational spectra of the solid is presented. The crystal structure as determined from three-dimensional single-crystal X-ray data collected by counter methods is described. A full-matrix least-squares refinement using 300 observed reflections resulted in a final R = 4.2%. The structure refines in the trigonal space group R3m. The hexagonal cell constants are a = 13.22 (1) ? and c = 5.72 (1) ? with V = 865.7 cm3, dc = 5.70 g/cm3, and Z = 9. The idealized coordination sphere of UOF4 consists of a pentagonal bipyramid of light atoms surrounding the central uranium. An oxygen atom and fluorine atom occupy indistinguishable axial positions with the U-O and U-F distances in the range 1.77-1.79 (3) ?. The equatorial belt contains one unique unbridged fluorine (U-Feq = 1.98 (3) ?) and four bridged fluorines (U-Fbr = 2.25-2.29 (3) ?). The observed chemistry and structure are compared and discussed in relation to transition metal oxide tetrafluorides and previously reported uranium oxide fluorides.
- Paine,Ryan,Asprey
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p. 1113 - 1117
(2008/10/08)
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- FLUORINATION OF URANIUM DIOXIDE BY BROMINE-FLUORINE SYSTEM.
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The addition of bromine to fluorine flow makes it possible to fluorinate UO//2 into UF//6 even below 200 degree C, at which temperature fluorination does not proceed with fluorine alone. Presence of bromine corresponding to about 6% of the fluorine concen
- Sakurai,Takahashi
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p. 308 - 313
(2008/10/08)
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- On the rate controlling step of UF4- BrF3 and U3O8- BrF3 reaction
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Experiments under varying diffusivity of BrF//3 brought about by changing the carrier gas showed that, compared with N//2 and Ar, He gas used as carrier brings about a reaction rate twice as high. These rates are affected by changes in neither linear gas velocity, BrF//3 partial pressure, nor reaction temperature; the ratio of the rates between the cases of He, N//2 and Ar is roughly equal to the theoretical ratio between the diffusivity of these three gases. The temperature dependence of the reaction reates also corresponds to the theoretical. The reactions are concluded to be diffusion controlled.
- SAKURAI T
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p. 176 - 181
(2008/10/08)
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- Complex compounds of uranium hexafluoride with sodium fluoride and potassium fluoride
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The reaction of UF6 with NaF goes to completion rapidly if the NaF is suspended in an inert solvent, C7F16. Two compounds are formed, NaUF7 and Na2UF8. Single crystals of Na2UF8 have been obtained. The Na2UF8 phase is body-centered tetragonal with a = 5.27 ?. and c = 11.20 ?. A model based on this symmetry and cell size leads to an eightfold coordination of fluorine atoms around each uranium atom, with all U-F distances equivalent. The preparation of the analogous compounds KUF7 and K2UF8 is also described.
- Malm, John G.,Selig, Henry,Siegel, Stanley
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p. 130 - 132
(2008/10/08)
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- Reactivity of transition metal fluorides. II. Uranium hexafluoride
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Reactions have been studied between uranium hexafluoride and a series of lower fluorides of other elements. The study has also included reaction with a wide range of covalent chlorides. The reactivity of uranium hexafluoride is compared with that of the higher fluorides of d-transition elements, chromium, molybdenum, and tungsten, and considered in the light of uranium as an f-transition element.
- O'Donnell,Stewart,Wilson
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p. 1438 - 1441
(2008/10/08)
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- Hexafluorides of molybdenum, tungsten, and uranium. II. Reactions with nitryl fluoride, nitrosyl fluoride, and nitrosyl chloride
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Reactions of three metal hexafluorides with nitrosyl and nitryl fluorides resulted in solid compounds of the composition NOxF·MF6 where x is 1 or 2 and M is W, Mo, or U. Infrared absorption data for these compounds indicate that the
- Geichman,Smith,Ogle
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p. 1012 - 1015
(2008/10/08)
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