From Impure Starting Material Patents (Class 423/484)
  • Publication number: 20130259793
    Abstract: A method for obtaining or recovering acids, in particular nitric acid and hydrofluoric acid, from solutions and/or metal salts of these acids containing solutions, comprising the steps of: a) spray-drying the solutions at temperatures below the decomposition temperature of the acids, the requisite energy for which is introduced via a gaseous heat-transfer medium, in order to obtain dry metal salts and gaseous acids; b) absorbing the gaseous acids formed in step a); c) separating out the dry metal salts formed in step a); optionally d) roasting the dry metal salts obtained in step a) at temperatures in the range from 400 to 900° C., in order to obtain metal oxides and gaseous acids; and e) absorbing the gaseous acids formed in step d).
    Type: Application
    Filed: April 18, 2011
    Publication date: October 3, 2013
    Applicant: KEY TECHNOLOGIES INDUSTRIEBAU GMBH
    Inventors: Gerhard Frithum, Herbert Klausner, Wilfried Szokol, Fabian Storek
  • Patent number: 8507396
    Abstract: A process for regenerating a used acidic catalyst which has been deactivated by conjunct polymers by removing the conjunct polymers so as to increase the activity of the catalyst is disclosed. Methods for removing the conjunct polymers include addition of a basic reagent and alkylation. The methods are applicable to all acidic catalysts and are described with reference to certain ionic liquid catalysts.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: August 13, 2013
    Assignee: Chevron U.S.A. Inc.
    Inventors: Saleh Elomari, Thomas V. Harris
  • Patent number: 8153095
    Abstract: Methods for producing highly pure solutions containing hydrogen fluoride, one or more salts thereof or a mixture of two or more thereof, by adding hydrogen fluoride to at least one anhydrous solvent, wherein the hydrogen fluoride is added to the anhydrous solvent or solvents in the form of a gas or as a liquified gas or as a mixture of gas and liquefied gas. High purity hydrogen fluoride and ammonium fluoride solutions produced by the inventive method are also disclosed.
    Type: Grant
    Filed: June 5, 2003
    Date of Patent: April 10, 2012
    Assignee: Honeywell International Inc.
    Inventors: Michael A. Dodd, John McFarland, Wolfgang Sievert
  • Patent number: 8153096
    Abstract: The present technology provides compositions that are intimate mixtures of hydrogen fluoride and a polyacrylate-polyacrylamide cross-linked copolymer, as well as methods and preparing and using such compositions. The compositions are less hazardous and, therefore, more conveniently stored, transported, and handled in comparison to pure hydrogen fluoride. Further, the hydrogen fluoride may be readily recovered from the compositions of the invention for use.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: April 10, 2012
    Assignee: Honeywell International Inc.
    Inventors: Matthew H. Luly, Bernard E. Pointner
  • Publication number: 20110286911
    Abstract: To provide a novel method for purifying hydrogen fluoride, capable of efficiently reducing the content of arsenic in hydrogen fluoride. The step (a) of bringing a crude hydrogen fluoride containing arsenic trifluoride into contact with an oxidizing agent of a metal fluoride in a liquid state is carried out, for example, in a reactor (11) to obtain a reaction mixture wherein arsenic pentafluoride is formed by oxidizing arsenic trifluoride with the oxidizing agent of the metal fluoride through a liquid-liquid reaction; and the step (b) of separating purified hydrogen fluoride from the reaction mixture is carried out, for example, by a separator (13), the thus obtained purified hydrogen fluoride having a lower content of arsenic than that of the crude hydrogen fluoride.
    Type: Application
    Filed: November 25, 2009
    Publication date: November 24, 2011
    Applicant: KYOTO UNIVERSITY
    Inventors: Rika Hagiwara, Kazuhiko Matsumoto
  • Patent number: 7914761
    Abstract: The present invention provides compositions that are intimate mixtures of hydrogen fluoride and a polyacrylate-polyacrylamide cross-linked copolymer. The compositions of the invention are less hazardous and, therefore, more conveniently stored, transported, and handled in comparison to pure hydrogen fluoride. Further, the hydrogen fluoride may be readily recovered from the compositions of the invention for use.
    Type: Grant
    Filed: June 4, 2008
    Date of Patent: March 29, 2011
    Assignee: Honeywell International Inc.
    Inventors: Matthew H. Luly, Bernard E. Pointner
  • Patent number: 7771699
    Abstract: The present invention relates to the conversion of waste and low-value materials into useful products in reliable purities in a cost-effective and energy-efficient manner. More specifially, the invention provides processes that can handle mixed streams of various feedstocks, e.g. shredder residue, offal, animal manures, municipal sewage sludge, tires, and plastics, that otherwise have little commercial value, to useful products including gas, oil, specialty chemicals, and carbon solids. The process subjects the feedstock to heat and pressure, separates out various components, then further applies heat and pressure to one or more of those components, according to processes based on thermal or catalytic cracking. The invention further comprises an apparatus for performing a multi-stage process of converting waste materials into useful materials, and at least one oil product that arises from the process. Useful products can also be obtained or derived from materials diverted at different points of the process.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: August 10, 2010
    Assignee: AB-CWT, LLC
    Inventors: Terry N. Adams, Brian S. Appel, Craig Timothy Einfeldt, James H. Freiss
  • Patent number: 7732363
    Abstract: A process for regenerating a used acidic catalyst which has been deactivated by conjunct polymers by removing the conjunct polymers so as to increase the activity of the catalyst is disclosed. Methods for removing the conjunct polymers include hydrogenation, addition of a basic reagent and alkylation. The methods are applicable to all acidic catalysts and are described with reference to certain ionic liquid catalysts.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: June 8, 2010
    Assignee: Chevron U.S.A. Inc.
    Inventors: Saleh Elomari, Thomas V. Harris
  • Publication number: 20090304571
    Abstract: The present invention provides compositions that are intimate mixtures of hydrogen fluoride and a polyacrylate-polyacrylamide cross-linked copolymer. The compositions of the invention are less hazardous and, therefore, more conveniently stored, transported, and handled in comparison to pure hydrogen fluoride. Further, the hydrogen fluoride may be readily recovered from the compositions of the invention for use.
    Type: Application
    Filed: June 4, 2008
    Publication date: December 10, 2009
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Matthew H. Luly, Bernard E. Pointner
  • Patent number: 7594952
    Abstract: A method of treating a spent potliner after use in an aluminum smelting process, the method comprising crushing and classifying the spent potliner, placing the classified and crushed spent potliner in a furnace at a temperature greater than 450° C., heating the spent potliner to a temperature greater than 450° C., mixing the heated spent potliner with water to produce reaction gases and residue, burning the reaction gases, mixing the residue with water in a well ventilated area for a period of weeks to cure the residue. The method also embraces blending the cured residue with other chemicals and minerals to provide specific mineral products.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: September 29, 2009
    Assignee: Regain Technologies Pty Ltd
    Inventors: Bernard John Cooper, Kevin Michael Cooper, Brendan Gerard Cooper, John Joseph Cooper
  • Publication number: 20080003172
    Abstract: Provided is a method for treating an aqueous feed stream containing an admixture of hexafluoroarsenic acid, or any salt thereof, and hydrogen fluoride, by contacting the feed stream with a counter-current stream of steam to remove substantially all of the hydrogen fluoride from the feed stream, and optionally to heat the feed stream. Further, provided is a method for continuously converting hexafluoroarsenic acid in an aqueous admixture, or any salt thereof, into arsenic acid by contacting the admixture with a counter-current stream of steam.
    Type: Application
    Filed: June 29, 2006
    Publication date: January 3, 2008
    Applicant: Honeywell International Inc.
    Inventors: Zenart Dziadyk, Paul F. Kunkel, Charles Redmon, Robert Smith
  • Patent number: 6884428
    Abstract: A biocompatible tissue repair stimulating implant or “scaffold” device is used to repair tissue injuries, particularly injuries to ligaments, tendons, and nerves. Such implants are especially useful in methods that involve surgical procedures to repair injuries to ligament, tendon, and nerve tissue in the hand and foot. The repair procedures may be conducted with implants that contain a biological component that assists in healing or tissue repair.
    Type: Grant
    Filed: December 16, 2002
    Date of Patent: April 26, 2005
    Assignee: DePuy Mitek, Inc.
    Inventors: Francois Binette, Steven M. Bowman, Izi Bruker, Julia Hwang, Mora Carolynne Melican, Alireza Rezania
  • Patent number: 6846418
    Abstract: A process for treating acidic and metallic waste water, particularly the rinsing water and/or used acids from pickling plants. The process includes the step of adding an alkaline solution or gas to bind the free acids in the waste water, followed by separation of the waste water into a first partial stream with high metal content and a second partial stream with low metal content. To achieve a more economical embodiment, particularly in terms of favorable energy consumption, and also reduce the nitrate load as much as possible, the free acids are bonded by adding ammonia solution or gas, and the first partial stream with the high metal content is fed to a regeneration plant to undergo pyrohydrolytic treatment, preferably by spray roasting. The second stream can be recycled to a rinse station.
    Type: Grant
    Filed: November 7, 2002
    Date of Patent: January 25, 2005
    Assignee: Andritz AG
    Inventor: Jovan Starcevic
  • Patent number: 6821351
    Abstract: The present invention relates to compositions, kits and processes for the brightening of metal surfaces by the application of the chemical compositions. These compositions act to release hydrofluoric acid as a brightening agent. The solutions are preferably mixed during application of the brightening composition to a metal surface by mixing the solutions immediately prior to or even during application of the solution. This can be readily accomplished by mixing two solutions, one having a fluoride source and the other having a strong acid to release hydrofluoric acid from the fluoride source, the mixing occurring immediately before spray application, during spraying, or immediately after spraying of the two solutions. Mixing may be done on-site, which means that mixing is performed at the site of use, usually on the same day of use or even within a few (less than 10) minutes of use.
    Type: Grant
    Filed: June 16, 2003
    Date of Patent: November 23, 2004
    Assignee: Ecolab Inc.
    Inventors: Guang-jong Jason Wei, David Daniel McSherry, Mark D. Levitt
  • Patent number: 6660893
    Abstract: A process for separating and recovering hydrogen fluoride from a mixture with an organic compound especially a fluorine-containing compound by extraction with a solution of an alkali metal fluoride in hydrogen fluoride, phase separation and recovery. A process for producing a fluorine-containing organic compound by fluorinating a starting material with hydrogen fluoride and similarly recovering hydrogen fluoride from the product stream. The solution may be anhydrous or aqueous.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: December 9, 2003
    Assignee: Ineca Fluor Holdings Limited
    Inventors: Paul Nicholas Ewing, Charles John Shields, Christopher Roberts
  • Patent number: 6605193
    Abstract: A method for isolating 32 from a crude mixture containing HCl and an azeotropic mixture of 32 and HF is provided without the need to isolate any HF azeotrope.
    Type: Grant
    Filed: April 25, 2001
    Date of Patent: August 12, 2003
    Assignee: Atofina Chemicals, Inc.
    Inventor: John A. Wismer
  • Patent number: 6579377
    Abstract: The present invention relates to compositions, kits and processes for the brightening of metal surfaces by the application of the chemical compositions. These compositions act to release hydrofluoric acid as a brightening agent. The solutions are preferably mixed during application of the brightening composition to a metal surface by mixing the solutions immediately prior to or even during application of the solution. This can be readily accomplished by mixing two solutions, one having a fluoride source and the other having a strong acid to release hydrofluoric acid from the fluoride source, the mixing occurring immediately before spray application, during spraying, or immediately after spraying of the two solutions. Mixing may be done on-site, which means that mixing is performed at the site of use, usually on the same day of use or even within a few (less than 10) minutes of use.
    Type: Grant
    Filed: August 26, 2002
    Date of Patent: June 17, 2003
    Assignee: Ecolab Inc.
    Inventors: Guang-jong Jason Wei, David Daniel McSherry, Mark D. Levitt
  • Patent number: 6555086
    Abstract: Processes for separating and recovering hydrogen fluoride from a gaseous mixture of an organic compound and hydrogen fluoride are disclosed. The processes include contacting the gaseous mixture with a solution of an alkali metal fluoride in hydrogen fluoride, separating a gas phase depleted in hydrogen fluoride and containing the organic compound from a liquid phase, and recovering hydrogen fluoride from the liquid phase.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: April 29, 2003
    Assignee: Ineos Fluor Holdings Limited
    Inventors: Paul Nicholas Ewing, Charles John Shields, Robert Elliott Low
  • Publication number: 20020168315
    Abstract: A process for separating and recovering hydrogen fluoride from a mixture with an organic compound especially a fluorine-containing compound by extraction with a solution of an alkali metal fluoride in hydrogen fluoride, phase separation and recovery. A process for producing a fluorine-containing organic compound by fluorinating a starting material with hydrogen fluoride and similarly recovering hydrogen fluoride from the product stream. The solution may be anhydrous or aqueous.
    Type: Application
    Filed: June 5, 2001
    Publication date: November 14, 2002
    Inventors: Paul Nicholas Ewing, Charles John Shields, Christopher Roberts
  • Publication number: 20020155057
    Abstract: Provided is a method for regulating the concentration of water in the acid feed stream in a process for the production of HF by the reaction with a fluorine containing material, the method comprising:
    Type: Application
    Filed: January 18, 2002
    Publication date: October 24, 2002
    Inventors: Troy W. Francisco, Charles L. Redmon, Kenneth E. Creasy, John L. Welch, William A. Pepe
  • Patent number: 6451274
    Abstract: The object of the present invention is to simplify the depleted UF6 processing plant and processing method and to prevent calcium fluoride to be a fine powder, wherein the processing plant comprises a first fluidized bed reactor for forming UO2F2 and hydrogen fluoride by allowing depleted UF6 to react with steam, a second fluidized bed reactor for forming U3Oa, hydrogen fluoride and oxygen by allowing UO2F2 to react with steam, a gas cooler for cooling hydrogen fluoride at 150 to 300° C., and a fluoride fixing reactor for forming calcium fluoride by allowing cooled hydrogen fluoride to contact calcium carbonate; and wherein the processing process comprises a dry vapor-phase reaction step for forcing UO2F2 and hydrogen fluoride by allowing depleted UF6 to react with steam at a temperature of 230 to 280° C.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: September 17, 2002
    Assignee: Mitsubishi Materials Corporation
    Inventor: Hiromichi Koizumi
  • Publication number: 20020127173
    Abstract: The invention relates to a process for utilizing waste salt mixtures from HALEX reactions, comprising at least one alkali metal chloride and at least one alkali metal fluoride or bifluoride, and optionally one or more organic compounds, which are depleted by extraction, by contacting the resulting waste salt mixture with concentrated sulfuric acid, removing the resulting hydrogen chloride for the most part by flushing with an inert gas, and reacting the salt-containing sulfuric acid with calcium fluoride to give hydrogen fluoride and alkali metal sulfate-containing calcium sulfate, which can be processed to give a building material binder.
    Type: Application
    Filed: January 10, 2002
    Publication date: September 12, 2002
    Inventors: Andreas Bulan, Joachim Herzig
  • Patent number: 6440224
    Abstract: A method of treating a surface of a metal is provided. A source of fluoride ion is mixed with a source of acid to form hydrofluoric acid and, when applied to a metal surface to be treated, the hydrofluoric acid acts as a brightening agent.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: August 27, 2002
    Assignee: Ecolab Inc.
    Inventors: Guang-jong Jason Wei, David Daniel McSherry, Mark D. Levitt
  • Patent number: 6428764
    Abstract: A process is disclosed for producing calcium fluoride. The process comprises (a) mixing phosphate rock with aqueous H2SiF6 at ambient temperature for at least one hour; (b) nucleating the calcium fluoride in the slurry prepared in step (a) by reacting the slurry at a temperature and for a time sufficient to initiate and sustain nucleation of calcium fluoride and SiO2 by-product; (c) aggregating the SiO2 by-product by heating the slurry produced in step (b) at a temperature of about 90° C. to about 105° C. for at least 0.5 hours; and (d) recovering a calcium fluoride-containing product of an average particle size of less than 1 micron.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: August 6, 2002
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: John Byrne Michel, Paul Douglas Vernooy
  • Patent number: 6423290
    Abstract: An organic solvent is separated from a waste stream comprising hydrofluoric acid, an organic solvent and etchant contaminants. The process comprises separating the hydrofluoric acid by subjecting the waste stream to at least one of the following processes: ion exchange; extraction of the hydrofluoric acid; electrophoresis; converting the hydrofluoric acid to an insoluble salt; to thereby obtain a first composition containing the hydrofluoric acid and a second stream containing the organic solvent and being substantially free of the hydrofluoric acid; and then distilling the second stream to recover the organic solvent free of the etching contaminants.
    Type: Grant
    Filed: May 31, 2000
    Date of Patent: July 23, 2002
    Assignee: International Business Machines Corporation
    Inventors: Anilkumar C. Bhatt, Jerome J. Wagner
  • Publication number: 20020063052
    Abstract: The invention relates to a novel process for removing arsenic compounds using amino/ammonium-functionalized anion exchangers from the distillation bottoms obtained in the purification of hydrogen fluoride by distillation.
    Type: Application
    Filed: October 4, 2001
    Publication date: May 30, 2002
    Inventors: Axel Peters, Gunter Lailach, Reinhold Klipper
  • Patent number: 6375915
    Abstract: In a method of regenerating a spent pickling solution composed of nitric acid and hydrofluoric acid and containing metal fluorides and metal nitrates, the pickling solution is heated in a reactor to about 300-1,000° C., the metal fluorides and the metal nitrates are pyrohydrolized, and the metal oxides formed as a result are removed as a granulate, and the gas produced in the fluodized bed reactor is dedusted, cooled and fed to an acid recovery unit. The spent pickling solution is initially separated in a separating process into a partial flow with free acid and into a partial flow enriched with metal salts, and the partial flow enriched with free acid is fed to the acid recovery unit and the partial flow enriched with metal salts is fed to the fluidized bed reactor.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: April 23, 2002
    Assignee: Keramchemie GmbH
    Inventors: Frank Bärhold, Werner Engelhardt
  • Patent number: 6350425
    Abstract: Provided is a novel method and system for preparing ultra-high-purity buffered-hydrofluoric acid or ammonium fluoride controlled concentration The method comprises bubbling purified ammonia vapor into ultra-pure hydrofluoric acid. The inventive method and system can be used as an on-site subsystem in a semiconductor device fabrication facility for supplying the buffered-hydrofluoric acid and ammonium fluoride to points of use in the semiconductor device fabrication facility.
    Type: Grant
    Filed: June 24, 1997
    Date of Patent: February 26, 2002
    Assignee: Air Liquide America Corporation
    Inventors: Joe G. Hoffman, R. Scot Clark
  • Patent number: 6346227
    Abstract: The novel process for preparing pure hydrofluoric acid or pure hydrogen fluoride is characterized in that, after pretreatment by distillatioil/oxidation, a two-stage scrub is carried out using 65-90% strength by weight hydrofluoric acid and 90-100% strength by weight hydrofluoric acid and water is fed into the first or second scrubbing circuit and a corresponding amount of hydrofluoric acid is bled off to remove impurities.
    Type: Grant
    Filed: February 4, 2000
    Date of Patent: February 12, 2002
    Assignee: Bayer Aktiengesellschaft
    Inventor: Günther Lailach
  • Publication number: 20010051128
    Abstract: Provided is a novel method and system for preparing ultra-high-purity buffered-hydrofluoric acid or ammonium fluoride controlled concentration. The method comprises bubbling purified ammonia vapor into ultra-pure hydrofluoric acid. The inventive method and system can be used as an on-site subsystem in a semiconductor device fabrication facility for supplying the buffered-hydrofluoric acid and ammonium fluoride to points of use in the semiconductor device fabrication facility.
    Type: Application
    Filed: June 24, 1997
    Publication date: December 13, 2001
    Inventors: JOE G. HOFFMAN, R. SCOT CLARK
  • Publication number: 20010022957
    Abstract: A process for purifying anhydrous HF by contacting anhydrous HF containing phosphate impurities with an effective amount of activated carbon so that the phosphate impurities are adsorbed on the activated carbon, and anhydrous hydrogen fluoride having a reduced phosphate impurity content is obtained.
    Type: Application
    Filed: December 19, 2000
    Publication date: September 20, 2001
    Inventors: Somanahalli Naranappa Subbanna, Charles Lewis Redmon, Robert Andrew Smith, Paul Frederick Kunkel
  • Patent number: 6270742
    Abstract: A process for separating and recovering hydrogen fluoride from a mixture with an organic compound especially a fluorine-containing compound by extraction with a solution of an alkali metal fluoride in hydrogen fluoride, phase separation and recovery. A process for producing a fluorine-containing organic compound by fluorinating a starting material with hydrogen fluoride and similarly recovering hydrogen fluoride from the product stream. The solution may be anhydrous or aqueous.
    Type: Grant
    Filed: April 8, 1998
    Date of Patent: August 7, 2001
    Assignee: Imperial Chemical Industries PLC
    Inventors: Paul Nicholas Ewing, Charles John Shields, Christopher Roberts
  • Patent number: 6224844
    Abstract: A process is disclosed for producing calcium fluoride comprising: (a) mixing aqueous H3PO4 with aqueous H2SiF6 to form a mixture such that the concentration of H3PO4 is at least about 3 moles/liter, (b) adding phosphate rock to the mixture at a rate such that the pH of the mixture is maintained at less than about 1.0 and at a temperature sufficient to form a second mixture containing calcium fluoride, and (c) separating calcium fluoride from the second mixture.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: May 1, 2001
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Paul Douglas VerNooy, John Byrne Michel
  • Patent number: 6217836
    Abstract: Spent potliner from aluminum reduction cells is treated, for example, with sulfuric acid to recover carbon, silica and alumina or to recover a vitrified product of silca and alumina.
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: April 17, 2001
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6217840
    Abstract: A method for producing fumed silica and a fluorine-containing product from a source of silica in solid form and a solid material containing fluorine, the solid material selected from the group consisting of sodium aluminum tetrafluoride, cryolite, aluminum fluosilicate ammonium bifluoride, sodium aluminum silicofluoride, and sodium fluosilicate. The method comprises the steps of digesting the silica in solid form and the solid material selected from the group consisting of sodium aluminum tetrafluoride, cryolite, aluminum fluosilicate, ammonium bifluoride, sodium aluminum silicofluoride, and sodium flurosilicate in a sulfuric acid digester. The digestion step produces a first gas component comprised of silicon tetrafluoride, hydrogen fluoride and water vapor. The first gas component is removed from the digester.
    Type: Grant
    Filed: August 13, 1999
    Date of Patent: April 17, 2001
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6207125
    Abstract: Flux residues from aluminium soldering fluxes composed of alkali metal metallates, especially fluoroaluminates of the alkali metals, in particular potassium and cesium, can be recycled by adding them to the reaction mixture used for the production of hydrogen fluoride from fluorspar and sulfuric acid or oleum. In this way the fluorine content of the flux residues becomes reusable, and the anhydrite which is produced can advantageously be used for conventional purposes.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: March 27, 2001
    Assignee: Solvay Fluor und Derivate GmbH
    Inventors: Ulrich Seseke-Koyro, Thomas Born
  • Patent number: 6193944
    Abstract: Spent potliner from an aluminum reduction cell is subject to an acid digest and the digest may be adjusted to produce a first gas component comprised of at least one material selected from the group consisting of silicon tetrafluoride, hydrogen fluoride, hydrogen cyanide gas and water vapor, and a slurry component comprised of at least one material selected from the group consisting of carbon, silica, alumina, and sodium, iron, calcium and magnesium compounds. The first gas component is removed from the digester and heated to a temperature sufficiently high to convert said silicon tetrafluoride to fumed silica and hydrogen fluoride. Thereafter, the fumed silica is separated from the hydrogen fluoride to recover fumed silica from spent potliner material.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: February 27, 2001
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6187275
    Abstract: A method of recovering AlF3 from spent potliner using an acid digest to form gaseous HF which is converted to hydrofluoric acid and reacted with alumina trihydrate to form AlF3.
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: February 13, 2001
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6183720
    Abstract: A process for producing a high-purity liquid chemical is provided. A chemical gas is successively purified over first and second purification columns by passing, countercurrently, a scrubbing solution of initially deionized high-purity water through the first and second purification columns, or by passing, countercurrently, a first scrubbing solution of initially deionized high-purity water through the first column and a second scrubbing solution of initially deionized water through the second column. Each of the scrubbing solutions gradually becomes a spent scrubbing solution loaded with impurity. A high-purity chemical gas leaves the second purification column with a low content of metallic elements. The high-purity chemical gas is subsequently dissolved in a liquid in a dissolution column including a top and a bottom. The liquid at the bottom of the dissolution column is collected and continuously recirculated, and is enriched with purified chemical gas, thereby forming a high-purity liquid chemical.
    Type: Grant
    Filed: April 8, 1998
    Date of Patent: February 6, 2001
    Assignee: Air Liquide Electronics Labeille
    Inventors: Thierry Laederich, Hervé Dulphy
  • Patent number: 6177058
    Abstract: The present invention provides compositions that are intimate mixtures of hydrogen fluoride and a polymer. The compositions of the invention are less hazardous and, therefore, more conveniently stored, transported, and handled in comparison to pure hydrogen fluoride. Further, the hydrogen fluoride may be readily recovered from the compositions of the invention for use.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: January 23, 2001
    Assignee: AlliedSignal Inc.
    Inventors: Rajiv Ratna Singh, Harold John Kieta, Matthew Hermes Luly, Jeffrey Warren McKown, Tadeusz Piotr Rygas, Ian Robert Shankland
  • Patent number: 6123908
    Abstract: A process of treating spent potliner material from aluminum reduction cells and recovering useful products. In the process of the present invention, spent potliner material is introduced into an acid digester containing, for example, sulfuric acid. As a result of this step, a gas component is produced which includes hydrogen fluoride, silicon tetrafluoride and hydrogen cyanide. Also, a slurry component is produced which includes carbon, a refractory material including silica, alumina, sodium compounds such as sodium sulfate, aluminum compounds such as aluminum sulfate, iron compounds such as iron sulfate, magnesium and calcium compounds such as magnesium and calcium sulfate. The slurry component remains in the digester after the gas component is removed. The gas component is recovered and heated an effective amount to convert or decompose the silicon tetrafluoride to fumed silica, hydrogen cyanide to a remaining gas component including CO.sub.2, H.sub.2 O, and nitrogen oxides, as well as HF gas.
    Type: Grant
    Filed: March 27, 1999
    Date of Patent: September 26, 2000
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6015477
    Abstract: Highly purified ammonia for use in processes for the production of high-precision electronic components is prepared on-site by drawing ammonia vapor from a liquid ammonia reservoir, passing the vapor through a filter capable of filtering out particles of less than 0.005 micron in size, and scrubbing the filtered vapor in a high-pH aqueous scrubber.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: January 18, 2000
    Assignee: Air Liquide America Corporation
    Inventors: Joe G. Hoffman, R. Scot Clark
  • Patent number: 5980850
    Abstract: Process for extraction or recovery of acids, in particular hydrofluoric acid, hydrochloric acid and nitric acid, from solutions of these acids containing metal, by pyrohydrolytic treatment and subsequent absorption and/or condensation of the acid gases thus formed in an aqueous absorption solution, in which process the solids produced are removed. In order to guarantee economical acid recovery in existing plants without requiring large-scale adaptation, the waste pickling liquor is subjected to pre-concentration first of all before pyrohydrolysis, using the heat contained in the exhaust gas from the pyrohydrolysis.
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: November 9, 1999
    Assignee: Andritz-Patentverwaltungs-Gesellschaft m.b.H.
    Inventor: Albert Lebl
  • Patent number: 5955042
    Abstract: A process for treating spent potliner material from aluminum reduction cells and recovering useful products. In the process, spent potliner material is introduced into an acid digester containing, for example, sulfuric acid. A gas component is produced which includes hydrogen fluoride and hydrogen cyanide. A slurry component is produced which includes carbon, silica, alumina, sodium compounds such as sodium sulfate, aluminum compounds such as aluminum sulfate, iron compounds such as iron sulfate, magnesium and calcium compounds such as magnesium and calcium sulfate. The slurry component remains in the digester after the gas component is removed. The gas component is recovered and heated an effective amount to convert or decompose the hydrogen cyanide to a remaining gas component including CO.sub.2, H.sub.2 O, and nitrogen oxides, as well as HF gas. The remaining gas component is directed through a water scrubber in which the HF gas is converted to liquid hydrofluoric acid.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: September 21, 1999
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 5948381
    Abstract: The invention provides a process for separating fluorinated organic compounds from mixtures of the such compounds and hydrogen fluoride. More particularly, the invention provides a method for separating a fluorinated organic compound from a mixture containing at least one fluorinated organic compound and hydrogen fluoride by adding an inorganic salt to the mixture.
    Type: Grant
    Filed: July 3, 1996
    Date of Patent: September 7, 1999
    Assignee: AlliedSignal Inc.
    Inventors: Richard Elmer Eibeck, Hang Thanh Pham, Valentine Theodore Zuba
  • Patent number: 5846386
    Abstract: Highly purified ammonia for use in semiconductor manufacturing is prepared on-site by drawing ammonia vapor from a liquid ammonia reservoir, passing the vapor through a filter capable of filtering out particles of less than 0.005 micron in size, and scrubbing the filtered vapor in a high-pH aqueous scrubber.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: December 8, 1998
    Assignee: Startec Ventures, Inc.
    Inventors: Joe G. Hoffman, R. Scott Clark
  • Patent number: 5846387
    Abstract: Highly purified HCl for use in semiconductor manufacturing is prepared on-site by drawing HCl vapor from a liquid HCl reservoir, and scrubbing the filtered vapor in a low-pH aqueous scrubber.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: December 8, 1998
    Assignee: Air Liquide Electronics Chemicals & Services, Inc.
    Inventors: Joe G. Hoffman, R. Scot Clark
  • Patent number: 5800795
    Abstract: Process for the recovery of hydrogen fluoride (HF) from a mixture, preferably an azeotropic mixture, of HF with water and/or an organic compound such as 134a, 125 or 133a, which comprises contacting the mixture with lithium fluoride or an alkaline earth metal fluoride to form a metal fluoride-hydrogen fluoride compound (e.g. lithium bifluoride, LiHF.sub.2), separating the compound and decomposing it to liberate hydrogen fluoride therefrom. The process is useful for recovering HF from azeotropic or azeotropic-like mixtures.
    Type: Grant
    Filed: October 9, 1997
    Date of Patent: September 1, 1998
    Assignee: Imperial Chemical Industries PLC
    Inventors: Thomas Anthony Ryan, John Graham Allen, Helen Marie Schoelzel, Massimino Ugo Pilotti
  • Patent number: 5785820
    Abstract: A system for purification and generation of hydrofluoric acid on-site at a semiconductor device fabrication facility. An evaporation stage (optionally with arsenic oxidation) is followed by a fractionating column to remove most other impurities, an Ionic Purifier column to suppress contaminants not removed by the fractionating column, and finally the HF Supplier (HFS).
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: July 28, 1998
    Assignee: Startec Ventures, Inc.
    Inventors: Joe G. Hoffman, R. Scot Clark
  • Patent number: 5766483
    Abstract: A method for separating hydrogen fluoride from a chemical mixture is provided. In the process of the invention, hydrogen fluoride is separated from a chemical mixture containing hydrogen fluoride by contacting the chemical mixture with a hydrogen fluoride binder. The separated hydrogen fluoride may be recovered from the hydrogen fluoride binder.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: June 16, 1998
    Assignee: AlliedSignal Inc.
    Inventors: Mathew Hermes Luly, Jeffrey Warren Mckown, Robert Pratt, Rajiv Ratna Singh, Paul Frederick Kunkel, Charles Lewis Redmon, Hang Thanh Pham