Refractory Metal (ti, Zr, Hf, V, Nb, Ta, Cr, Mo, Or W) Patents (Class 423/492)
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Patent number: 6399033Abstract: An improvement to the chloride process of making titanium dioxide. By recycling some of the cyclone dust, the yield in the chlorination of titanium-containing raw materials can be increased. In order to prevent silica accumulation in the fluidized bed, the cyclone dust is divided into two fractions. An economic solution is described of a single-stage separation of the cyclone dust in a hydrocyclone, the majority of the titanium dioxide occurring in the hydrocyclone underflow, although the separation is not sharp. By grinding and drying the solids from the hydrocyclone underflow, the titanium dioxide particles returned to the lower region of the fluidized-bed reactor are rapidly chlorinated, while the quartz and coke particles are rapidly discharged again from the fluid bed, so that no silica contamination occurs.Type: GrantFiled: November 3, 1995Date of Patent: June 4, 2002Assignee: Kronos, Inc.Inventor: Achim Hartmann
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Publication number: 20010016182Abstract: The present invention is a process for controlling, at an aim point, the passivation of aluminum chloride in the chlorinator discharge stream in a process for making titanium tetrachloride.Type: ApplicationFiled: December 18, 2000Publication date: August 23, 2001Inventors: James Timothy Cronin, Thomas Shields Elkins, Hans Hellmut Glaeser, Lisa Edith Helberg, Angela Ruth Strzelecki
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Patent number: 6210800Abstract: Separable nanotubes are made from a transition metal oxide, preferably from a vanadium oxide of variable valence. They show a greater oxidation resistance than the carbon-based nanotubes known so far and offer many new and economic applications. The inventive nanotubes clearly show oxidation-reduction activities and are particularly suited as an active material for catalytic reactions.Type: GrantFiled: August 4, 1999Date of Patent: April 3, 2001Assignee: Eidg. Technische Hochschule ZurichInventors: Reinhard Nesper, Michael E. Spahr, Markus Niederberger, Petra Bitterli
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Patent number: 6136060Abstract: A method for refining a titanium metal containing ore such as rutile or illmenite or mixtures to produce titanium ingots or titanium alloys and compounds of titanium involves production of titanium tetrachloride as a molten slag, by processing the ore in a chlorination procedure and removing various impurities by a distillation or other procedure to form a relatively pure titanium tetrachloride (TiCl.sub.4). Thereafter, the titanium tetrachloride is introduced into the plasma focal point of a plasma reactor in a molten sodium environment for the initial reduction of gas phase titanium into titanium molten drops which are collected by a set of skulls. Thereafter, further processing are carried out in higher vacuum and the titanium is heated by electron beam guns in order to maximize titanium purity and, in a final optional stage, alloying compounds are added under yet higher vacuum and high temperature conditions.Type: GrantFiled: October 16, 1998Date of Patent: October 24, 2000Inventor: Adrian A. Joseph
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Patent number: 6096281Abstract: A method for producing uranium oxide includes combining uranium oxyfluoride and a solid oxidizing agent having a lower thermodynamic stability than the uranium oxide after "oxide"; heating the combination below the vapor point of the uranium oxyfluoride to sufficiently react the uranium oxyfluoride and the oxidizing agent to produce uranium oxide and a non-radioactive fluorine compound; and removing the fluorine compound after "compound".Type: GrantFiled: March 29, 1999Date of Patent: August 1, 2000Assignee: Starmet CorporationInventors: John B. Bulko, Bridget M. Smyser
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Patent number: 6028026Abstract: This invention provides a crystalline chromium fluoride having a cubic crystal structure (i.e., chromium trifluoride having an X-ray diffraction powder pattern as shown in Table I); and a catalytic composition comprising cubic chromium trifluoride. This invention also provides a process for changing the fluorine content of halogenated hydrocarbons containing from one to six carbon atoms, in the presence of a chromium-containing catalyst. The process is characterized by the chromium-containing catalyst comprising cubic chromium trifluoride.Type: GrantFiled: August 20, 1998Date of Patent: February 22, 2000Assignee: E. I. du Pont de Nemours and CompanyInventors: V. N. Mallikarjuna Rao, Munirpallam A. Subramanian
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Patent number: 5948212Abstract: A process for the separation of a mixture of a titanium tetrahalide, a reaction diluent of an intermediate boiling point and at least one of a titanium alkoxide, ester or complex thereof without the aid of a distinct separation solvent by subjecting the mixture to a first distillation step to separate the titanium tetrahalide as the lights component and subjecting the heavies product to a second distillation step to recover a portion of the reaction diluent as the lights component.Type: GrantFiled: October 21, 1996Date of Patent: September 7, 1999Assignee: Union Carbide Chemicals & Plastics Technology CorporationInventors: Peter Anthony Kilty, Michael Philip Zum-Mallen, Michael Wayne Potter
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Patent number: 5918106Abstract: A method for producing uranium oxide includes combining uranium tetrafluoride and a solid oxidizing agent having a lower thermodynamic stability than the uranium oxide; heating the combination below the vapor point of the uranium tetrafluoride to sufficiently react the uranium tetrafluoride and the oxidizing agent to produce uranium oxide and a non-radioactive fluorine compound; and removing the fluorine compound.Type: GrantFiled: June 5, 1998Date of Patent: June 29, 1999Assignee: Starmet Corp.Inventors: John B. Bulko, William T. Nachtrab
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Patent number: 5683669Abstract: In the preparation of metal chlorides from their elements to be used as additives in processes of making titanium dioxide by the chloride process, a titanium tetrachloride stream is directed to sweep over the lined inner wall of a metal chloride generator to act as a protective film, which considerably increases the life of the generator. Furthermore, the titanium tetrachloride is further heated, which is highly desirable in the chloride process. When the titanium tetrachloride is optionally conducted in advance through ducts in the lining of the inner walls of the metal chloride generator, its temperature can be further raised.Type: GrantFiled: March 26, 1996Date of Patent: November 4, 1997Assignee: Kronos Inc.Inventors: Achim Hartmann, Herman Trub
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Patent number: 5670121Abstract: This invention relates to a process for controlling the temperature of a fluidized bed reactor in the manufacture of titanium tetrachloride, wherein an exhaust gas stream comprising carbonyl sulfide, sulfur dioxide, carbon monoxide, carbon dioxide, and chlorine is formed. In the process, the exhaust gas stream is first analyzed to determine the analyzed concentration of carbonyl sulfide (or concentration ratio of carbonyl sulfide to sulfur dioxide), the desired concentration of carbonyl sulfide (or concentration ratio of carbonyl sulfide to sulfur dioxide) in the exhaust gas stream is determined, and the difference between the analyzed concentration of carbonyl sulfide (or concentration ratio of carbonyl sulfide to sulfur dioxide) and the desired concentration of carbonyl sulfide (or concentration ratio of carbonyl sulfide to sulfur dioxide) in the exhaust gas stream is then calculated.Type: GrantFiled: May 5, 1995Date of Patent: September 23, 1997Assignee: E. I. Du Pont de Nemours and CompanyInventor: Thomas Shields Elkins
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Patent number: 5624490Abstract: A process for preparing high strength, rock-like, water-resistant aggregates by high intensity mixing of acidic metal chlorides and alkaline/cementitious materials in the presence of a low water ratio wherein the metal chlorides are simultaneously neutralized/stabilized and the mixture is solidified.Type: GrantFiled: August 25, 1995Date of Patent: April 29, 1997Assignee: E. I. Du Pont de Nemours and CompanyInventors: Peter Hill, Michael T. Hyzny, John F. Wehner
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Patent number: 5569440Abstract: An improved carbochlorination process for the production of volatile metal chlorides is disclosed. When chlorine gas contacts a metal oxide or a mixed metal oxide in a reaction zone in the presence of carbon at elevated temperatures, an undesirable carbochlorination residue forms containing carbon in the reaction zone. After the build-up of a carbochlorination residue in the reaction zone occurs, the volume of the carbochlorination residue in the reaction zone is reduced by periodically introducing just chlorine and metal oxide or mixed metal oxide reactants into the reaction zone without introducing any additional carbon. These components react with a portion of the carbon in the carbochlorination residue so as to reduce the amount of the residue.Type: GrantFiled: September 14, 1994Date of Patent: October 29, 1996Assignee: Teledyne Industries, Inc.Inventor: James A. Sommers
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Patent number: 5437854Abstract: Zirconium tetrachloride containing hafnium tetrachloride is selectively reduced with liquid metallic tin to produce zirconium trichloride. The hafnium tetrachloride is then separated as a vapor from a slurry of zirconium trichloride and other solids, including stannous dichloride, in liquid metallic tin.Type: GrantFiled: June 27, 1994Date of Patent: August 1, 1995Assignee: Westinghouse Electric CorporationInventors: Roy G. Walker, Carlos L. Aguilar
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Patent number: 5397807Abstract: Disclosed is a compatibilized carbon black useful in melt processing of plastic material. The carbon black is coated with a compatibilizing agent which enhances the dispersibility of the carbon black in a melt of the plastic material. Further disclosed are processes for making plastic foam structures with the compatibilized carbon black.Type: GrantFiled: May 27, 1994Date of Patent: March 14, 1995Assignee: The Dow Chemical CompanyInventors: Martin K. Hitchcock, Kyung W. Suh, Arnold M. Bartz, Andrew N. Paquet, William G. Stobby
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Patent number: 5389353Abstract: In a fluidized bed process for chlorinating rirnium-containing material, an improvement is disclosed comprising utilizing in the process calcined petroleum shot coke, calcined petroleum fluid coke or mixtures thereof. The improved process is capable of (a) decreasing the amount of fine particulate coke that is entrained in the hot gases exiting the fluidized bed reactor, and (b) more completely reacting the coke.Type: GrantFiled: February 1, 1994Date of Patent: February 14, 1995Assignee: E. I. Du Pont de Nemours and CompanyInventors: Hans H. Glaeser, Mark J. Spoon
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Patent number: 5320815Abstract: In a fluidized bed process having a bed of fluidized particulate material which is susceptible to having at least some of the particulate material being entrained in the gases exiting the bed, the entrainment is reduced by introducing the particulate material into the process, in the substantial absence of a gas which transports the particulate material, at one or more points which are below the surface of the bed of fluidized particulate material.Type: GrantFiled: September 30, 1992Date of Patent: June 14, 1994Assignee: E. I. Du Pont de Nemours and CompanyInventors: Ran Abed, James W. Reeves
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Patent number: 5300273Abstract: An improved process is provided for producing titanium tetrachloride vapor admixed with a desired particular amount of aluminum trichloride vapor for use in the production of rutile titanium dioxide. The vapor mixture is derived from a titanium tetrachloride solution containing the desired particular amount of aluminum trichloride. The solution is produced continuously by dissolving aluminum trichloride in a heated stream of liquid titanium tetrachloride utilizing a cyclic aluminum trichloride bed switching and recharging process.Type: GrantFiled: December 3, 1992Date of Patent: April 5, 1994Assignee: Kerr-McGee Chemical CorporationInventor: Robert E. Leonard
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Patent number: 5290745Abstract: A catalyst system of the Ziegler-Natta type suitable for producing ethylene copolymers having a reduced hexane extractable content comprising (a) an organoaluminum component and (b) a titanium trichloride component which has been prepared by reducing titanium tetrachloride with magnesium metal.Type: GrantFiled: August 10, 1992Date of Patent: March 1, 1994Assignee: Union Carbide Chemicals & Plastics Technology CorporationInventors: Robert J. Jorgensen, Elton D. Fowler, George L. Goeke
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Patent number: 5277889Abstract: Metal halide compositions of enhanced purity are produced by vapor phase deposition via reactions involving organometallic starting materials in a process wherein a carbon getter is provided in the reaction zone and/or adjacent the developing metal halide deposit. The carbon getter reduces carbon contamination in the product which can result from side decomposition reactions involving the organometallic starting materials.Type: GrantFiled: May 13, 1985Date of Patent: January 11, 1994Assignee: Corning IncorporatedInventors: Joseph M. Power, Ahmad Sarhangi
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Patent number: 5242549Abstract: An improved process for separation of valuable components of a waste stream resulting from production of an olefin polymerization procatalyst by the addition to the waste stream of a separation solvent of intermediate boiling point, subjecting the resulting mixture to a first distillation zone to separate the desired waste stream components from the upper portion of the zone and passing the bottoms product to a second distillation zone wherein separation solvent is recovered from the upper portion of the zone for recycle and passing the bottoms product to disposal or further processing.Type: GrantFiled: December 6, 1991Date of Patent: September 7, 1993Assignee: Shell Oil CompanyInventors: Michael W. Potter, Stephen W. Cowan, Robert S. Tomaskovic
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Patent number: 5224986Abstract: This invention provides a process for the recovery of titanium values from a complex matrix comprising titanium nitride. The process comprises chlorinating the titanium nitride in the matrix to obtain a reaction product containing titanium chloride, and separating the titanium chloride from the reaction product. The invention also provides for the production of said complex matrix containing titanium nitride by nitriding titanium values in complex titanium-containing starting materials such as complex metallurgical titaniferous slags and ilmenite, perovskite, armalcolite and fassaite.Type: GrantFiled: July 24, 1991Date of Patent: July 6, 1993Inventors: Gerhard J. Mostert, Bodo R. Rohrmann, Roger J. Wedlake, Rodney C. Baxter
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Patent number: 5171551Abstract: Solid catalyst substrates based on zirconium dioxide and, optionally, titanium dioxide and/or cerium dioxide, e.g., honeycombs or monoliths, are well adapted for the desulfurization and catalytic conversion of industrial gases containing contaminating amounts of objectionable sulfur compounds.Type: GrantFiled: September 17, 1990Date of Patent: December 15, 1992Assignee: Rhone-Poulenc ChimieInventor: Eric Quemere
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Patent number: 5171549Abstract: An improved halogenator process and system is provided which significantly and economically decreases the level of impurities in the processing of various refractory metals and their halides and particularly hafnium tetrachloride which is condensed from gases produced by the chlorination of Zircon.Type: GrantFiled: May 22, 1991Date of Patent: December 15, 1992Assignee: Teledyne Wah Chang AlbanyInventors: Ronald E. Walsh, Jr., Peter W. Krag, Roy E. Blackstone, Duane L. Hug
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Patent number: 5169808Abstract: Metal carbides can be formed by the pyrolysis of a composition comprising metal and carboxylic acid residues bonded therein, the composition being substantially free of extraneous carbon and also having metal moieties that are not in the substituent position. Dicarboxylic acids, for example, can be reacted with either metal alkoxides or metal halides to form an oligomer or polymer which can be calcined to the metal carbide. Alternatively, a metal alkoxide can be reacted with a monocarboxylic acid to form a metal alkoxide carboxylate which can be heated to the metal carbide. Finally, a metal carboxylate can be heated to form the desired metal carbide.Type: GrantFiled: April 10, 1992Date of Patent: December 8, 1992Assignee: Akzo nvInventors: Thomas A. Gallo, Carl C. Greco
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Patent number: 5120523Abstract: A metal is dissolved by a method which comprises establishing contact of the metal with a quaternary ammonium compound and a halogenated hydrocarbon or with a quaternary ammonium compound, a halogenated hydrocarbon, and a polar solvent.Type: GrantFiled: October 26, 1990Date of Patent: June 9, 1992Assignee: Agency of Industrial Science & Technology, Ministry of International Trade & IndustryInventors: Yukimichi Nakao, Kyoji Kaeriyama, Aizo Yamauchi
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Patent number: 5091168Abstract: A method of producing an anhydrous niobium or tantalum pentafluoride involving reacting the corresponding pentoxide or oxyhalide with an excess of anhydrous hydrogen fluoride in the presence of a sufficient dehydrating agent (e.g., COCl.sub.2, SOCl.sub.2 or SO.sub.2 Cl.sub.2) to react with any water formed. Such a process is useful to produce a catalyticallyactive anhydrous niobium or tantalum pentafluoride in essentially a single liquid phase reaction step.Type: GrantFiled: August 15, 1990Date of Patent: February 25, 1992Assignee: E. I. Du Pont de Nemours and CompanyInventor: Mario J. Nappa
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Patent number: 5080880Abstract: A process relating to the hydrolysis of metal halides and their production of corresponding metal oxides by the hydrolysis of their chlorides and the calcining of the hydrolysis product is disclosed. Novel aspect including obviating the neutralizing step for the hydrochloric acid by using ammonia and disposing of the resulting ammonium chloride and the two step addition initially of metal halides to water until there is no observable positive heat of reaction and then adding the metal halide in amounts up to the stoichiometric quantity for the hydrolysis product obtained.Type: GrantFiled: June 13, 1989Date of Patent: January 14, 1992Assignee: Teledyne Industries, Inc.Inventor: John R. Peterson
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Patent number: 5073355Abstract: A process for the removal of chlorine from off-gases which continuously or sporadically contain small amounts of chlorine by scrubbing the off-gases with a ferrous chloride-containing aqueous solution in a scrubbing system. The solution used is obtained by dissolving a solids mixture which results from the chlorination of a titaniferous and ferriferous feedstock material and which contains essentially ferrous chloride. This solution is used in particular for the scrubbing of off-gases formed in the production of titanium dioxide by the chlorination of titaniferous and ferriferous feedstock material, thus generating titanium tetrachloride and ferrous chloride, and by the reaction of the titanium tetrachloride with oxygen-containing gases. It is preferably the solids mixture separated in this process from the chlorination mixture in a condensation step that is dissolved in the process of the invention, and at least part of the resulting solution is used for the scrubbing of the off-gases.Type: GrantFiled: July 5, 1990Date of Patent: December 17, 1991Assignee: Kronos (U.S.A.), Inc.Inventor: Achim Hartmann
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Patent number: 5032372Abstract: An improved dilute phase chlorination procedure characterized by providing extremely finely divided oxygen-containing metallic material and a carbonaceous material co-milled together to a particle size size of less than 20 microns. The finely divided charge material is introduced into a tubular reaction zone, preferably at the bottom, with the gaseous chlorination agent where reaction occurs at a temperature above 800.degree. C. for a period of time sufficient to fully react the chlorinating agent in a single pass. Metal chloride is recovered from the tubular reactor and, most advantageously, there is little or no need to separate any dusty unreacted solid material from the off-gases for recycle to the chlorination zone.Type: GrantFiled: October 6, 1989Date of Patent: July 16, 1991Assignee: SCM Chemicals, Inc.Inventor: James P. Bonsack
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Patent number: 5009866Abstract: Continuous production of zirconium and/or hafnium metal from a fused salt bath in which one of the salts is zirconium and/or hafnium tetrachloride is carried out by feeding additional, make-up zirconium and/or hafnium tetrachloride powder into a zirconium and/or hafnium dissolution area of the bath maintained at a dissolution temperature below which the tetrachloride will vaporize, by circulating portions of the bath into and through a separate but contiguous area maintained at a temperature at which the tetrachloride will vaporize, and by recovering the vaporized tetrachloride. It is preferred that the vaporization area of the bath be wholly surrounded by and insulated from the dissolution area of the bath.Type: GrantFiled: November 16, 1989Date of Patent: April 23, 1991Assignee: Westinghouse Electric Corp.Inventor: Ernest D. Lee
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Patent number: 5009751Abstract: Separation of hafnium tetrachloride from zirconium tetrachloride by introducing zirconium tetrachloride containing about 2-4 wt percent of hafnium tetrachloride into an electrolytic cell filled with a molten salt and dissolving it to make an electrolytic bath. Running first phase electrolysis which produces zirconium trichloride containing a lower hafnium content than the dissolved zirconium tetrachloride at the cathode. Running second phase electrolysis using the first cathode, but switching the first cathode to become an anode and using a second cathode. Producing zirconium trichloride of a lower hafnium content than the dissolved zirconium tetrachloride at the second cathode. Evolving a gaseous zirconium trichloride at the anode by electrolytic oxidation of the zirconium trichloride produced in the first phase electrolysis. Recovering this evolved zirconium tetrachloride which has a lower hafnium content than the dissolved zirconium tetrachloride and the zirconium trichloride produced at the cathodes.Type: GrantFiled: January 5, 1989Date of Patent: April 23, 1991Assignee: Mitsubishi Nuclear Fuel Company, Ltd.Inventors: Tomoo Kirihara, Ippei Nakagawa, Yoshinobu Seki, Yutaka Honda, Yasuo Ichihara
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Patent number: 4965055Abstract: Metal halides are ultrapurified by selective complexation with a complexing gent to form a charged first complex. A ligand forms an oppositely charged second complex with metallic impurities in the metal halide to be purified. A solution containing these complexes is then passed through an ion exchange column and the desired purified metal halide collected. The present method is particularly useful in the production of ultrapure metal halides, such as zirconium fluorinate, for metallic glasses.Type: GrantFiled: March 27, 1990Date of Patent: October 23, 1990Assignee: The United States of America as represented by the Secretary of the NavyInventors: Paul E. R. Nordquist, Jr., Arnold H. Singer
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Patent number: 4961911Abstract: A process for reducing the amount of carbon monoxide emitted from a fluidized bed reactor for chlorinating titanium bearing material containing iron oxide comprising (a) feeding coke, titanium bearing material containing iron oxide, and chlorine to the reactor, the chlorine being fed to the reactor below the surface of the fluidized bed, (b) maintaining the feed rate of the materials in step (a) and the conditions of operation of the bed so that the iron oxide is substantially converted to ferrous chloride, and (c) feeding sufficient chlorine to the reactor at or near the surface of the bed to convert the desired amount of carbon monoxide to carbon dioxide.Type: GrantFiled: March 2, 1989Date of Patent: October 9, 1990Assignee: E. I. Du Pont de Nemours and CompanyInventors: Paul G. Reis, Michael J. Dunbar
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Patent number: 4957722Abstract: A process for producing chlorides by the chlorination of a material selected from the group consisting of aluminous materials and metal and metalloid oxides in the presence of a reductant. The method comprises calcining a carbonaceous material with added steam to oxidize substantially all precursors of chlorinated hydrocarbons and to form a reductant; and chlorinating a material selected from the group consisting of aluminous materials and metal oxides in the presence of the reductant.Type: GrantFiled: April 3, 1989Date of Patent: September 18, 1990Assignee: Aluminum Company of AmericaInventors: Raouf O. Loutfy, Kirk R. Weisbrod, James C. Withers
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Patent number: 4948632Abstract: A method for selecting preferred coating reactants by thermal analysis of decomposition is disclosed along with a preferred coating reactant comprising dibutyltin difluoride in polymolecular form.Type: GrantFiled: May 21, 1985Date of Patent: August 14, 1990Assignee: PPG Industries, Inc.Inventor: J. Shannon Breininger
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Patent number: 4933154Abstract: A ZrO.sub.2 powder of very fine particle size adapted especially for the making of high density ceramics is produced by chlorinating a zirconium source material, such as zircon sand, to produce crude ZrCl.sub.4 solids; the solids are dissolved to form a ZrOCl.sub.2 solution from which ZrOCl.sub.2 crystals are precipitated; the crystals are dried and milled to a desired particle size; and the crystal particles are subjected to direct oxidation under controlled conditions to produce a very fine ZrO.sub.2 powder especially adapted to the making of high density ceramics.Type: GrantFiled: January 30, 1987Date of Patent: June 12, 1990Assignee: Westinghouse Electric Corp.Inventor: Young J. Kwon
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Patent number: 4923507Abstract: The subject of the invention is a process for opening ores, particularly ores containing tantalum, niobium, zirconium and titanium, of the kind that includes the stages of leaching with mineral acids, solvent extraction, purification and separation of the products obtained, characterized by the fact that initially, instead of leaching with sulfuric acid and hydrofluoric acid being performed as a first stage, the original ore concentrate is melted together with fluorite (CaF.sub.2), followed by milling of the melting product obtained and subsequently leaching with concentrated sulfuric acid, followed by extraction of the soluble species using solvents, separation and purification of the products obtained.Type: GrantFiled: May 19, 1988Date of Patent: May 8, 1990Assignee: Mamore Mineracao E Metalurgia S/AInventor: Egberto Silva, Filho
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Patent number: 4923577Abstract: This is a method of reducing zirconium chloride to a metal product by introducing zirconium chloride into a molten salt bath containing at least one alkali metal chloride and at least one alkaline earth metal chloride; and electrochemically reducing alkaline earth metal chloride to a metallic alkaline earth metal in the molten salt bath, with the reduced alkaline earth metal reacting with the zirconium chloride to produce zirconium metal. By using this electrochemical-metallothermic reduction, zirconium metal is produced and insoluble subchlorides of zirconium in the metal product are generally avoided.Preferably, the molten salt in the molten salt bath consists essentially of a mixture of lithium chloride, potassium chloride, magnesium chloride and zirconium or hafnium chloride.Type: GrantFiled: September 12, 1988Date of Patent: May 8, 1990Assignee: Westinghouse Electric Corp.Inventors: David F. McLaughlin, Francis Talko
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Patent number: 4913778Abstract: Removal of aluminum and iron impurities is accomplished using an absorbing column containing potassium or sodium chloride, producing an aluminum and iron chloride-rich bottoms product and purified Zr(Hf)Cl.sub.4 vapor at the top of the column. This invention is a continuous process for removing impurities of iron or aluminum chloride or both from vaporous zirconium chloride (or hafnium chloride or a mixture thereof). When iron is being removed from zirconium tetrachloride using potassium chloride, the process comprises: introducing impure zirconium chloride vapor into a middle portion of an absorbing column containing a potassium chloride-containing molten salt phase, the molten salt phase absorbing the iron chloride impurity to produce a zirconium chloride vapor stripped of iron chloride in the top portion of the column; introducing potassium chloride into a top portion of the column; controlling the top portion of the column to between 300.degree.-375.degree. C.Type: GrantFiled: January 2, 1989Date of Patent: April 3, 1990Assignee: Westinghouse Electric Corp.Inventors: Ernest D. Lee, David F. McLaughlin
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Patent number: 4910009Abstract: The process for purifying a contaminated chloro, bromo or iodo precursor salt of zirconium, hafnium or aluminum by means of providing a molten thermal body of one or more alkali or alkaline earth metal halides and the precursor salt containing impurities, maintaining the body at a temperature sufficient to volatilize the precursor salt away from its impurities while effecting a reducing condition in the body by means of a fluid, mobile reducing agent which is non-reducing of said precursor salt, and isolating the purified volatilized precursor salt from the body. The ultra purified isolated volatilized precursor salt can then be reacted with a fluorinating agent to produce the highly purified fluoride for use in optical fiber grade glass or the like.Type: GrantFiled: May 6, 1988Date of Patent: March 20, 1990Assignee: Teledyne Industries, Inc.Inventor: James A. Sommers
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Patent number: 4897116Abstract: The process for preparing zirconium, hafnium, vanadium, tantalum, or niobium metal comprising providing in first vessel means a eutectic solution of a chloro, bromo or iodo salt of zirconium or hafnium in a molten thermal body of one or more alkali or alkaline earth metal halides at a non-vaporizing temperature, transferring said eutectic solution to second vessel means, maintaining said second vessel means at a temperature sufficient to vaporize said salt, transferring the salt vapor independently to a bank of separately fed reduction crucibles, the supply of said eutectic solution to said second vessel means being maintained such that said salt vapor can be supplied substantially continuously to said crucibles in a selective manner dependent upon the operating status of each crucible.Type: GrantFiled: May 25, 1988Date of Patent: January 30, 1990Assignee: Teledyne Industries, Inc.Inventor: Randall L. Scheel
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Patent number: 4885019Abstract: Heavy metal fluoride glasses are made by a process that requires high purity fluoride constituent compounds fluorinated oxides, or premelted glass cullet. The charge is placed in an enclosed furnace chamber having the ability of atmosphere control, heat control and position control of the charge. In particular, an inert, or nonreactive atmosphere or air is used in the furnace chamber as well as an oxygen-scavenging metal therein. The oxygen-scavenging metal at the high temperature produces a controlled oxygen partial pressure so that the air is essentially inert and non-reactive although the presence of a slightly oxidizing atmosphere is still required to produce the glass. The charge is rapidly raised to its fusion temperature and held at the temperature for a short time in proximity to an oxygen-scavenging material. The charge is immediately removed from the heating source and quickly cooled through the critical crystallization region. The total heating and cooling time being less than one hour.Type: GrantFiled: January 28, 1988Date of Patent: December 5, 1989Assignee: The United States of America as represented by the Secretary of the Air ForceInventor: Joseph J. Hutta
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Patent number: 4874475Abstract: Improvements are described to a process in which the extractive distillation separation of zirconium or hafnium may be accomplished using mixtures of fused alkali metal or alkali metal and alkaline earth chlorides as the solvent. The solvent composition is adjusted to provide a low-melting eutectic, permitting recirculation of the stripped solvent in the liquid phase, as well as reducing the temperature required for thermal stripping (reducing the corrosivity of the fluid). Stripping of the bottoms is accomplished at least partially by direct electrolysis of the bottoms stream, producing the zirconium-free salt recycle stream to be transferred to the top of the column, and at least partially eliminating the need for chemical reduction of the tetrachlorides to metal (a costly process generating undersirable waste streams). Regeneration of the reflux is accomplished in a presurized condenser system, of one or more stages, with all material transport to be done in either the liquid or vapor states.Type: GrantFiled: September 12, 1988Date of Patent: October 17, 1989Assignee: Westinghouse Electric Corp.Inventors: David F. McLaughlin, Richard A. Stoltz
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Patent number: 4865693Abstract: This is a zirconium-hafnium separation process utilizing a complex of zirconium-hafnium chlorides and phosphorus oxychloride. The complex is introduced into a distillation column and a hafnium chloride enriched stream is taken from the top of the column and a zirconium chloride enriched stream is taken from the bottom of the column. In particular, the invention utilizes prepurification of the zirconium-hafnium chlorides prior to introduction of the complex into the distillation column to substantially eliminate iron chloride; thus, the buildup of iron chloride in the distillation column is substantially eliminated and the column can be operated in a continuous stable, and efficient manner.Type: GrantFiled: September 12, 1988Date of Patent: September 12, 1989Assignee: Westinghouse Electric Corp.Inventor: David F. McLaughlin
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Patent number: 4865694Abstract: This is an improved method for separating hafnium from zirconium of the type where a complex of zirconium and hafnium chlorides and phosphorus oxychloride is prepared from zirconium-hafnium chloride and the complex is introduced into a distillation column, with the improvement comprising: electrochemical breaking of the zirconium of hafnium chloride complex taken from said distillation column to separate product from the complex. The electrochemical breaking of the complex, possibly by reducing zirconium or hafnium, is done in a molten salt bath. Preferably, the molten salt in said molten salt bath consists principally of a mixture of alkali metal and alkaline earth metal chlorides and zirconium or hafnium chloride. The product can be either chloride, metal, or mixed metal and subchloride for further processing.Type: GrantFiled: September 12, 1988Date of Patent: September 12, 1989Assignee: Westinghouse Electric Corp.Inventors: Thomas S. Snyder, Richard A. Stoltz, David F. McLaughlin
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Patent number: 4865695Abstract: This is a method for molten salt systems related to distillation for zirconium-hafnium separation and prevents buildup of iron chloride by electrochemically reducing iron from the molten salt to give very low levels of iron chloride in the distillation column, to reduce corrosion, improve the product and, in some cases, to allow the molten salt system to be run continuously. The improvement comprises electrochemical purification of molten salt containing zirconium-hafnium chloride either, prior to introduction of the zirconium-hafnium chloride into a distillation column, or after introduction, or both, to substantially eliminate iron chloride from the zirconium-hafnium chloride. The molten salt during the electrochemical purification consists essentially of a mixture of chlorides of alkali metals, alkaline earth metals, zirconium, hafnium, aluminum, manganese, and/or zinc.Type: GrantFiled: September 12, 1988Date of Patent: September 12, 1989Assignee: Westinghouse Electric Corp.Inventors: Thomas S. Snyder, Richard A. Stoltz
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Patent number: 4865696Abstract: This is a process for removing phosphorus oxychloride from a complex of zirconium or hafnium chloride and phosphorus oxychloride utilizing a lithium-potassium chloride molten salt absorber vessel displacing phosphorous oxychloride from the complex, with a condenser which has the complex of zirconium or hafnium chloride and phosphorus oxychloride as the condensing fluid to scrub zirconium or hafnium chloride from the phosphorus oxychloride vapor released from the complex. The process uses at least one separate vessel to strip the zirconium or hafnium chloride from the lithium-potassium chloride molten salt.Type: GrantFiled: September 12, 1988Date of Patent: September 12, 1989Assignee: Westinghouse Electric Corp.Inventors: David F. McLaughlin, Richard A. Stoltz
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Patent number: 4863706Abstract: A process for producing acidic boratozirconium chloride sols which comprises: reacting a zirconium compound with a boron compound in molar ratios of B/Zr of 0.3-1.2 together with a compound of a metal M, the metal M being selected from the group consisting of divalent, trivalent, tetravalent and pentavalent metals in molar ratios of M/Zr of about 0.01-1 in water in the presence of chloride ions in molar ratios of Cl/Zr of not less than about 1.The acidic boratozirconium chloride sol may be converted to basic boratozirconium sols by reacting the acidic sol with a basic carbonate compound such as ammonium carbonate.The sols, either acidic or basic, are readily gelled by contact with a dehydration solvent such as methanol or actone.The gel is calcined at relatively low temperatures to provide zirconia which is either very pure or stabilized in varied degrees.Type: GrantFiled: November 10, 1987Date of Patent: September 5, 1989Assignee: Takeda Chemical Industries, Ltd.Inventors: Takeo Wada, Hiroshi Onaka, Hideaki Matsuda
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Patent number: 4853205Abstract: Process of using supercritical fluid to selectively separate, purify and recover metal halides.Type: GrantFiled: March 12, 1987Date of Patent: August 1, 1989Assignee: The United states of America as represented by the Secretary of the InteriorInventors: William K. Tolley, Alton B. Whitehead
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Patent number: 4803062Abstract: In a method for producing tungsten hexachloride which comprises reacting tungsten with chlorine gas at a temperature sufficient to result in the conversion of the tungsten to tungsten hexachloride, the improvement comprising reacting tungsten in the form of pressed pieces to convert the pieces to tungsten hexachloride having an oxygen content of less than about 0.5% by weight with the rate of conversion to tungsten hexachloride being at least about 2.3 times greater than the rate of conversion when the tungsten is in an unpressed form.Type: GrantFiled: April 14, 1988Date of Patent: February 7, 1989Assignee: GTE Products CorporationInventors: Robin W. Munn, Robert P. McClintic, Kenneth T. Reilly