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ELECTROCHEMISTRY OF MOLTEN SALTS. Period Covered: June 1, 1954 to June 1, 1956

Description: A new back-emf method for measuring the thermodynamic emf of molten salt cells of the type M/MCl/sub 2/ in molten salt solvent/Cl/sub 2/ is presented. Decomposition potentials are measured in the course of the thermodynamic emf determination. The systems PbCl/sub 2/-ZrCl/sub 2/, LiCl-KCl eutectic, LiCl-KCl- NdCl/sub 3/, MgCl/sub 2/ in LiClKCl and NaCl, SnCl/sub 2/, KCl, and PbCl/sub 2/, and ZnCl/sub 2/ in LiClKCl eutectic were studied. The thermodynamic emf's obtained by the back-emf method are in good agreement with values calculated from independent thermochemical data. Thus Raoult's law is thought to apply in these simple systems to within a factor of two in the activity coefficient. (auth)
Date: June 1, 1956
Creator: Roland, E.H. & Pound, G.M.
Partner: UNT Libraries Government Documents Department

Darex Process: Processing of Stainless Steel-Containing Reactor Fuels with Dilute Aqua Regia

Description: From abstract: "The Darex process developed for the recovery of uranium from stainless steel-containing reactor fuels consists of three steps: (1) dissolution of the fuel material in dilute aqua regia, (2) removal of chloride from the solution to prevent corrosion of downstream stainless steel process equipment, and (3) adjustment of the nitrate solution to solvent extraction feed conditions."
Date: June 7, 1962
Creator: Kitts, F. G.
Partner: UNT Libraries Government Documents Department

Electrostatic Modeling of Vacuum Insulator Triple Junctions

Description: A comprehensive matrix of 60 tests was designed to explore the effect of calcium chloride vs. sodium chloride and the ratio R of nitrate concentration over chloride concentration on the repassivation potential of Alloy 22. Tests were conducted using the cyclic potentiodynamic polarization (CPP) technique at 75 C and at 90 C. Results show that at a ratio R of 0.18 and higher nitrate was able to inhibit the crevice corrosion in Alloy 22 induced by chloride. Current results fail to show in a consistent way a different effect on the repassivation potential of Alloy 22 for calcium chloride solutions than for sodium chloride solutions.
Date: August 13, 2007
Creator: Tully, L. K.; White, A. D.; Goerz, D. A.; Javedani, J. B. & Houck, T. L.
Partner: UNT Libraries Government Documents Department

Dehydration of plutonium trichloride hydrate

Description: A process of preparing anhydrous actinide metal trichlorides of plutonium or neptunium by reacting an aqueous solution of an actinide metal trichloride selected from the group consisting of plutonium trichloride or neptunium trichloride with a reducing agent capable of converting the actinide metal from an oxidation state of +4 to +3 in a resultant solution, evaporating essentially all the solvent from the resultant solution to yield an actinide trichloride hydrate material, dehydrating the actinide trichloride hydrate material by heating the material in admixture with excess thionyl chloride, and recovering anhydrous actinide trichloride is provided.
Date: December 31, 1991
Creator: Foropoulos, J. Jr.; Avens, L.R. & Trujillo, E.A.
Partner: UNT Libraries Government Documents Department

Repassivation Potential of Alloy 22 in Sodium and Calcium Chloride Brines

Description: A comprehensive matrix of 60 tests was designed to explore the effect of calcium chloride vs. sodium chloride and the ratio R of nitrate concentration over chloride concentration on the repassivation potential of Alloy 22. Tests were conducted using the cyclic potentiodynamic polarization (CPP) technique at 75 C and at 90 C. Results show that at a ratio R of 0.18 and higher nitrate was able to inhibit the crevice corrosion in Alloy 22 induced by chloride. Current results fail to show in a consistent way a different effect on the repassivation potential of Alloy 22 for calcium chloride solutions than for sodium chloride solutions.
Date: August 11, 2007
Creator: Rebak, R B; Ilevbare, G O & Carranza, R M
Partner: UNT Libraries Government Documents Department

Phase equilibria in the system H{sub 2}O-NaCl-KCl-MgCl{sub 2} relevant to salt cake processing

Description: One waste product in recycling of Al is salt cake, a mixture of Al, salts, and residue oxides. Several methods have been proposed to recycle salt cake, one involving high-temperature leaching of salts from the salt cake. The salt composition can be approximated as a mixture predominantly of NaCl and KCl salts, with lesser amounts of Mg chloride. In order to better assess the feasibility of recycling salt cake, an experimental study was conducted of phase equilibria in the system H{sub 2}O-NaCl-KCl-MgCl{sub 2} at pressure (P), temperature (T), and composition conditions appropriate for high- temperature salt cake recycling. These experiments were designed to evaluate the effect of small amounts (2-10 wt%) of MgCl{sub 2} on solubilities of halite (NaCl) and sylvite (KCl) in saturated solutions (30-50 wt% NaCl+KCl; NaCl:KCl = 1:1 and 3:1) at elevated P and T.
Date: February 1, 1997
Creator: Bodnar, R.J.; Vityk, M.O.; Hryn, J.N. & Mavrogenes, J.
Partner: UNT Libraries Government Documents Department

TRANSFERENCE NUMBERS AND ION ASSOCIATION IN PURE FUSED ALKALINE EARTH CHLORIDES

Description: The transference number of the chloride ion was determined in pure fused MgCl/sub 2/, CaCl/sub 2/, SrCl/sub 2/, and BaCl/sub 2/ utili zing radioactive chloride ions in a porous quartz membrane cell. On the basis of a two-step dissociation for these salts, MCl/sub 2/ in equilibrium MCl/sup +/ + Cl/sup -/ in equilibrium Ml/sup +/ + 2Cl/sup -/, the ext ent of the second dissociation was qualitatively predicted from a consideration of the relative mobilities of the ions. (auth)
Date: March 27, 1962
Creator: Wolf, E.D. & Duke, F.R.
Partner: UNT Libraries Government Documents Department

INVESTIGATION FOR THE PRODUCTION OF THORIUM METAL. Technical Progress Report--Fifth Quarter

Description: Processes for preparing a suitable ThCl/sub 4/ electrolyte free of H/sub 2/O and C/sub 2/ were investigated including chlorination with C -Cl/sub 2/, sulfur chlorides, NaCl, and preparation from anhydrous solvents. The method selected consisted of reacting ThOCO/sub 3/ with HCl, adding NH/sub 4/Cl, and heating in inert atmosphere to drive off NH/sub 4/Cl. (T.R.H.)
Date: December 17, 1953
Creator: Merlub-Sobel, M.
Partner: UNT Libraries Government Documents Department

Ketene Reactions: I. The Addition of Acid Chlorides to Dimethylketene ; II. The Cycloaddition of Ketenes to Carbonyl Compounds

Description: Part I describes the addition of several acid chlorides to dimethylketene. The resulting 3-ketoacid chlorides were isolated and characterized. Part II describes the cycloaddition of several aldoketenes to chloral. The ketenes were generated in situ by dehydrohalogenation and dehalogenation of appropriately substituted acyl halides.
Date: December 1970
Creator: Smith, Larry
Partner: UNT Libraries

Fiber Optical Micro-detectors for Oxygen Sensing in Power Plants

Description: A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. Our approach towards immobilizing the potassium salt of the molybdenum cluster, K{sub 2}Mo{sub 6}Cl{sub 14}, at the far end of an optical fiber is to embed the cluster in a thermally cured sol-gel matrix particle. Due to the improved mechanical properties of this approach high temperature sensor measurements were performed up to 100 C. These are promising results for a high temperature fiber optical oxygen sensor based on molybdenum chloride clusters.
Date: September 30, 2006
Creator: Baker, Gregory L.; Ghosh, Ruby N.; Osborn, D. J. & Zhang, Po
Partner: UNT Libraries Government Documents Department

Long-Term Corrosion Behavior of Alloy 22 in 5 M CaCl2 at 120?C

Description: In conditions where tight crevices exist in hot chloride containing solutions Alloy 22 may suffer crevice corrosion. The occurrence (or not) of crevice corrosion in a given environment (e.g. salt concentration and temperature), is governed by the values of the critical potential (E{sub crit}) for crevice corrosion and the corrosion potential (E{sub corr}). This paper discusses the evolution of E{sub corr} and corrosion rate (CR) of creviced Alloy 22 specimens in 5 M calcium chloride (CaCl{sub 2}) at 120 C. Tested specimens included non-creviced rods and multiple creviced assemblies (MCA) both non-welded (wrought) and welded. Results show that Alloy 22 suffers crevice corrosion under the open circuit conditions in the aerated hot CaCl{sub 2} brine. However, after more than a year immersion the propagation of crevice corrosion was not significant. The general corrosion rate decreased or remained unchanged as the immersion time increased. For rods and MCA specimens, the corrosion rate was lower than 100 nm/year after more than a year immersion time.
Date: February 5, 2006
Creator: Estill, J C; Hust, G A; Evans, K J; Stuart, M L & Rebak, R B
Partner: UNT Libraries Government Documents Department

Moessbauer Spectra and Magnetic Susceptibilities of Cs{sub 2}NpCl{sub 6}, (TMA){sub 2}NpCl{sub 6}, and (TEA){sub 2}NpCl{sub 6}

Description: This paper reports additional information obtained from low-temperature magnetic susceptibilities and Moessbauer spectra on Cs{sub 2}NpCl, ((Ch{sub 3}){sub 4}N){sub 2}NpCl{sub 6}, and ((C{sub 2}H{sub 4}){sub 4}N){sub 2}NpCl{sub 6}. The structures of these compounds are inferred from their isostructural uranium and plutonium analogues and the infrared spectral studies.
Date: March 15, 2001
Creator: Karraker, D.G.
Partner: UNT Libraries Government Documents Department

The chemistry of boron and titanium diboride formation: Decomposition of TiCl{sub 4} and BCl{sub 3} in hydrogen and helium

Description: Measurements of the decomposition of mixtures of boron trichloride (BCl{sub 3}), titanium tetrachloride (TiCl{sub 4}), and hydrogen at elevated temperatures are presented. The decomposition of BCl{sub 3} with hydrogen appears to drive the chemistry in this system. The species depositing boron on the surface contains at least 2 chlorine atoms. Once deposited, the surface chlorine is removed by reaction with hydrogen to form HCl and, presumably, surface B-H bonds.
Date: December 1995
Creator: Osterheld, T. H. & Allendorf, M. D.
Partner: UNT Libraries Government Documents Department

Purification of aqueous plutonium chloride solutions via precipitation and washing.

Description: Pyrochemical operations at Los Alamos Plutonium Facility (TA-55) use high temperature melt s of calcium chloride for the reduction of plutonium oxide to plutonium metal and hi gh temperature combined melts of sodium chloride and potassium chloride mixtures for the electrorefining purification of plutonium metal . The remaining plutonium and americium are recovered from thes e salts by dissolution in concentrated hydrochloric acid followed by either solvent extraction or io n exchange for isolation and ultimately converted to oxide after precipitation with oxalic acid . Figur e 1 illustrates the current aqueous chloride flow sheet used for plutonium processing at TA-55 .
Date: January 1, 2003
Creator: Stroud, M. A. (Mary Ann); Salazar, R. R. (Richard R.); Abney, Kent David; Bluhm, E. A. (Elizabeth A.) & Danis, J. A. (Janet A.)
Partner: UNT Libraries Government Documents Department