Purification Or Recovery Patents (Class 570/177)
  • Patent number: 6972094
    Abstract: Upon recovering a fluorochemical surfactant from a fluorochemical-containing aqueous solution, there is provided a method for recovering the fluorochemical surfactant from the aqueous solution containing the surfactant. In the method, the fluorochemical surfactant is recovered by subjecting the aqueous solution containing the fluorochemical surfactant to a filtration treatment step with a reverse osmosis membrane so as to obtain from the aqueous solution, a concentrated aqueous solution in which the concentration of the fluorochemical surfactant is increased.
    Type: Grant
    Filed: August 8, 2001
    Date of Patent: December 6, 2005
    Assignee: Daikin Industries, Ltd.
    Inventors: Takuya Ichida, Masahiro Kondo
  • Patent number: 6967260
    Abstract: Tetrafluoromethane containing ethylene compound, hydrocarbon compounds, carbon monoxide and/or carbon dioxide is contacted with zeolite having an average pore size of 3.4 to 11 ? and an Si/Al ratio of 1.5 or less and/or a carbonaceous adsorbent having an average pore size of 3.4 to 11 ?. Thus, high-purity tetrafluoromethane can be obtained which is advantageous in industry and provides good profitability.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: November 22, 2005
    Assignee: Showa Denko K.K.
    Inventors: Hiromoto Ohno, Toshio Ohi
  • Patent number: 6927312
    Abstract: Disclosed are improved fluorination processes and fluorine-containing compositions which involve introducing to one or more fluorination process compositions a water reactive agent in an amount and under conditions effective to decrease the amount of water in that composition. The water reactive agent is preferably introduced to the fluorination reaction process at a location proximate to the site of the fluorination reaction, or upstream of the fluorination reaction, in amounts and under conditions effective to produce a relatively lower concentration of water in the composition, and preferably throughout the fluorination process.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: August 9, 2005
    Assignee: Honeywell International Inc.
    Inventors: Jason T. Stuck, Hsueh Sung Tung, Michael Van Der Puy, Timothy R. Demmin, Franklin S. Wong, Andrew J. Poss, Matthew H. Luly
  • Patent number: 6900362
    Abstract: A process for the production of HFC-227ea from HF and HFP is provided. This process takes advantage of an azeotropic composition of HF and HFC-227ea in order to produce HFC-227ea essentially free of HF and recycle unreacted HF back to the reactor. The recycle of said azeotropic composition, also allows the use of HFC-227ea as a diluent to aid in control of reactor temperature for a highly exothermic reaction.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: May 31, 2005
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Ralph Newton Miller, Mario J. Nappa, Donald J. Toton
  • Patent number: 6897344
    Abstract: Divalent and trivalent metal salts are added to the solution containing the fluorine compound to precipitate the layered double hydroxide containing the fluorine compound between layers. By these processes, the fluorine compound can be fixed with high rate. Moreover, if necessary, the precipitated layered double hydroxide can be recovered to separate the fluorine compound or its salt between layers. Therefore, the burden to environment or the ecosystem by the fluorine compound can be reduced.
    Type: Grant
    Filed: July 26, 2001
    Date of Patent: May 24, 2005
    Assignee: Jemco Inc.
    Inventors: Kiyoshi Fuda, Toshiaki Matsunaga, Takeshi Kamiya, Kota Omori
  • Patent number: 6849772
    Abstract: 1,1-Difluoroethane containing less than 10 mg/kg of vinyl chloride is obtained by treatment, with hydrogen fluoride, of a crude 1,1-difluoroethane containing less than 1 mol of hydrogen chloride per mole of 1,1-difluoroethane.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: February 1, 2005
    Assignee: Solvay (Societe Anonyme)
    Inventors: Charles-Marie Anciaux, Vincent Wilmet, Dominique Lecroc
  • Patent number: 6825043
    Abstract: A method of increasing the fluorous nature of a compound includes the step of reacting the compound with at least one second compound having the formula: wherein Rf is a fluorous group, Rs is a spacer group, d is 1 or 0, m is 1, 2 or 3, Ra is an alkyl group and X is a suitable leaving group. A compound has the formula: wherein Rf is a fluorous group, n is an integer between 0 and 6, m is 1, 2 or 3, Ra is an alkyl group and X is a leaving group.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: November 30, 2004
    Assignee: University of Pittsburgh
    Inventors: Dennis P. Curran, Roger Read, Zhiyong Luo
  • Publication number: 20040236162
    Abstract: Process for the obtention of HFC-227ea having a reduced content of organic impurities, comprising at least subjecting a crude HFC-227ea to two distillation steps at different pressures.
    Type: Application
    Filed: March 5, 2004
    Publication date: November 25, 2004
    Inventors: Thomas Muller, Dominique Balthasart, Bernd Kutzner
  • Publication number: 20040236161
    Abstract: The present invention relates to processes for reducing the concentration of acidic impurities HF, HCl, HBr, HI, HNO3 and H2SO4 in fluorinated hydrocarbons. The process involves: (i) contacting the fluorinated hydrocarbon with a phosphorous oxyacid salt, and (ii) recovering the fluorinated hydrocarbon having reduced concentration of, or substantially free of, said acidic contaminant, provided that said fluorinated hydrocarbon is not CF3CH2CF3 or CF3CHFCF3.
    Type: Application
    Filed: May 23, 2003
    Publication date: November 25, 2004
    Inventors: Velliyur Nott Mallikarjuna Rao, Allen C. Sievert
  • Patent number: 6787678
    Abstract: Disclosed are improved fluorination processes and fluorine-containing compositions which involve introducing to one or more fluorination process compositions a water reactive agent in an amount and under conditions effective to decrease the amount of water in that composition. The water reactive agent is preferably introduced to the fluorination process at a location downstream of the fluorination reaction, in amounts and under conditions effective to produce a relatively lower concentration of water in the composition, and preferably throughout the fluorination process.
    Type: Grant
    Filed: December 11, 2003
    Date of Patent: September 7, 2004
    Assignee: Honeywell International Inc.
    Inventors: Hsueh Sung Tung, Jason T. Stuck
  • Publication number: 20040167366
    Abstract: A process is disclosed for purifying a hydrofluoropropane of undesirable C2-C4 olefinic and C1-C4 saturated chlorinated impurities, comprising the steps of: contacting a first mixture of hydrofluoropropane, olefinic impurity and saturated chlorinated impurity with hydrogen and hydrogen fluoride concurrently in the presence of a bifunctional catalyst, for example an alloy of gold and palladium supported on carbon, capable of catalyzing hydrogenation and fluorination. During the contacting step, olefinic impurity is converted to saturated hydrogenated derivative and/or saturated hydrofluorinated derivativ, and saturated chlorinated impurity is converted to a saturated hydrodechlorinated derivative and/or saturated fluorinated derivative. The hydrofluoropropane thus formed is substantially free of both the olefinic and saturated chlorinated impurities and may be used as obtained or subject to further purification steps such as distillation to remove the process derivatives (e.g.
    Type: Application
    Filed: December 11, 2003
    Publication date: August 26, 2004
    Inventors: Velliyur Nott Mallikarjuna Rao, Allen C. Sievert
  • Patent number: 6774270
    Abstract: A method of removing hexafluoropropylene dimers (“HFP dimers”), dimer hydrides and other oligomers from a fluid is described. The method comprises heating the fluid to isomerize the HFP dimers to the thermodynamic isomer, and contacting the fluid with a tertiary amine (or salts thereof) to form a hexafluoropropylene dimer—tertiary amine adduct. The method may further comprise the step of separating the dimer adducts from the reaction mixture.
    Type: Grant
    Filed: April 1, 2003
    Date of Patent: August 10, 2004
    Assignee: 3M Innovative Properties Company
    Inventors: Zhongxing Zhang, Zai-Ming Qiu, Daniel R. Vitcak, Richard M. Flynn
  • Publication number: 20040133051
    Abstract: A process for removing one or more unsaturated halocarbons from a halocarbon mixture comprising one or more unsaturated halocarbons and one or more saturated halocarbons, which process comprises contacting the halocarbon mixture with a mixture of a solid chemical oxidant and a solid support in the presence of water.
    Type: Application
    Filed: February 5, 2004
    Publication date: July 8, 2004
    Inventors: Stephen Andrew Flaherty, Paul Hendry Stewart
  • Patent number: 6743957
    Abstract: Divalent and trivalent metal salts are added to the solution containing the fluorine compound and the polymer containing fluorine to precipitate the layered double hydroxide containing the fluorine compound between layers. At this time, the polymer containing fluorine suspended in the solution is also coagulated to precipitate. By these processes, the fluorine compound is fixed with high rate to separate from the solution with the polymer containing fluorine, and recovered if necessary. By this treatment process, the fluorine compound and the polymer containing fluorine, contained in the wastewater etc. can be separated easily, and the burden to environment or ecosystem can be reduced.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: June 1, 2004
    Assignee: JEMCO, Inc.
    Inventors: Kiyoshi Fuda, Toshiaki Matsunaga, Takeshi Na Kamiya, Kota Omori
  • Patent number: 6720465
    Abstract: A process for preparing purified, saturated, partially fluorinated or perfluorinated hydrocarbon compounds from crude products which are contaminated with impurity compounds which absorb light at a wavelength of &lgr;>200 nm by irradiating the crude product with UV radiation of a wavelength of &lgr;>200 nm and thereafter recovering highly pure, partially fluorinated or perfluorinated hydrocarbon compounds from the irradiated reaction product, for example, by simple vacuum distillation.
    Type: Grant
    Filed: March 4, 2002
    Date of Patent: April 13, 2004
    Assignee: Solvay Fluor und Derivate GmbH
    Inventors: Max Braun, Carsten Brosch, Heinz Gress
  • Patent number: 6710216
    Abstract: In a closed-loop biomass extraction apparatus (10), strategies for purifying HFC solvents used therein include: (i) contacting an adsorbent and a desiccant, e.g. in a container (26) with contaminated HFC solvent branched from the main flow loop; and, optionally, (ii) washing contaminated HFC solvent with water, e.g. in a vessel (34) to separate a co-solvent or entrainer, such as ethanol, thereform.
    Type: Grant
    Filed: September 5, 2000
    Date of Patent: March 23, 2004
    Assignee: Imperial Chemical Industries PLC
    Inventors: Stuart Corr, Paul A. Dowdle, Robert E. Low, James David Morrison, Frederick Thomas Murphy
  • Patent number: 6673264
    Abstract: The invention relates to azeotropic and azeotrope-like mixtures of 1,1,1,3,3-pentafluorobutane (HFC-365) and hydrogen fluoride and a process for separating the azeotrope-like mixtures. The compositions of the invention are useful as an intermediate in the production of HFC-365. The latter is useful as a nontoxic, zero ozone depleting fluorocarbon useful as a solvent, blowing agent, refrigerant, cleaning agent and aerosol to propellant.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: January 6, 2004
    Assignee: Honeywell International Inc.
    Inventors: Hang T. Pham, Rajiv R. Singh, Hsueh S. Tung
  • 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: 6646171
    Abstract: A process for the crystallisation of a sterically hindered organic compound from a saturated or supersaturated solution of said compound in a solvent therefor, characterised in that crystallisation is effected under elevated pressure at a temperature above the boiling point of said solution at atmospheric pressure and up to the boiling point of said solution at said elevated pressure.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: November 11, 2003
    Assignee: Amersham Health AS
    Inventor: Jan Cervenka
  • Patent number: 6642415
    Abstract: Fluorinated emulsifiers, in particular, perfluorooctanoic acid are bound to anionic exchange resins for the purification of aqueous effluent from the production of fluoropolymers. Said emulsifiers may be quantitatively eluted from the exchanger with a water-miscible organic solvent, containing a small amount of ammonia. It is of advantage to distil off the ammonia containing solvent, recycle the emulsifier to a further polymerization and recycle the ammoniacal solvent for elution. Addition of alkalis improves the elution efficiency.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: November 4, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Stephan Führer, Klaus Hintzer, Gernot Löhr, Werner Schwertfeger
  • Publication number: 20030164283
    Abstract: The present invention involves processes that utilize an olefinic compound, in particular, hexafluoropropene (HFP) or chlorotrifluoroethene (CFC-1113) as extracting agents in the purification of pentafluoroethane (HFC-125). These processes can utilize recovered HFP as a precursor for the production of heptafluoropropane (HFC-227) or other derivatives.
    Type: Application
    Filed: February 14, 2002
    Publication date: September 4, 2003
    Inventors: Stephan M. Brandstater, Mitchel Cohn, Victoria E. Hedrick, Yuichi Iikubo
  • Publication number: 20030121769
    Abstract: The invention relates to the purification of pentafluoroethane (F125) containing chloropentafluoroethane (F115) by liquid/liquid extraction or by extractive distillation.
    Type: Application
    Filed: September 16, 2002
    Publication date: July 3, 2003
    Inventors: Emmanuel Guiraud, Cathy Descamps
  • 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
  • Patent number: 6552238
    Abstract: Provided is a method and system for separating heavy ends from a halogenated alkane in a waste stream. The method includes: (a) removing a bottom fraction containing heavy ends from a catalyst recovery unit and conveying the bottom fraction to a vessel; (b) introducing steam into the bottom fraction containing heavy ends; (c) removing a halogenated alkane vapor and a water vapor from the waste treatment unit; (d) condensing the halogenated alkane and water vapors; and (e) separating the halogenated alkane phase and water phase from the heavy ends.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: April 22, 2003
    Assignee: Vulcan Chemicals
    Inventors: Eric L. Mainz, Richard L. Wilson
  • Patent number: 6540882
    Abstract: The invention relates to a process of separation of mixtures containing HFC-365mfc/HF azeotropic compositions by two distillations at different pressures, as well as to a process of synthesis of HFC-365mfc which integrates this process of separation and a recycling of certain fractions towards the hydrofluorination step.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: April 1, 2003
    Assignee: Solvay (Societe Anonyme)
    Inventors: Ferdinand Reif, Dominique Balthasart
  • Patent number: 6521803
    Abstract: Process for the separation of a mixture comprising at least one hydrofluoroalkane and hydrogen fluoride, according to which a hydrofluoroalkane/hydrogen fluoride mixture is reacted with at least one chlorinated or chlorofluorinated precursor of the hydrofluoroalkane. Process for the preparation of a hydrofluoroalkane comprising such a separation, in combination with a catalytic reaction stage. Azeotropic compositions.
    Type: Grant
    Filed: July 17, 2001
    Date of Patent: February 18, 2003
    Assignee: Solvay (Societe Anonyme)
    Inventors: Alain Lambert, Vincent Wilmet
  • Patent number: 6521461
    Abstract: A method for removing one or more fluorinated alkenes from a fluid comprises the step of contacting the fluid with an N-, S-, or P-containing nucleophile for a time sufficient to form an N-, S-, or P-containing nucleophile-fluoroalkene adduct. The nucleophile, and therefore the adduct, can be covalently bonded, coated or sorbed to a particulate support which can be enmeshed in a porous, fibrous web. In a preferred embodiment the fluorinated alkene can have the formula wherein A=F or Rf; X=H, F, Cl, Rf, or YRf; Z= H, F, Cl, or Rf; and Y=O, N, or S; with the proviso that at least one A=F, and at most one of Z and X is H; wherein each Rf is independently selected from the group consisting of highly fluorinated or perfluorinated alkyl groups; and a combination of any two Rf groups can be linked to form a cyclic structure. The Rf alkyl chains may contain from 1-20 carbon atoms, with 1-12 carbon atoms preferred.
    Type: Grant
    Filed: June 14, 2001
    Date of Patent: February 18, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Mark Eugene Mueller, Donald Frederick Hagen, Yuri Cheburkov, Fred Lynn DeRoos, Glenn Delmont Johnson, John Stephen Marhevka, Venkateswarlu Pothapragada
  • Patent number: 6512150
    Abstract: A gaseous process for reducing the amount of chloropentafluoroethane (CFC 115) impurity present in pentafluoroethane (HFC 125) characterized in that pentafluroethane is allowed to flow on a catalyst formed by a trivalent chromium salt, optionally supported, at temperatures in the range 200° C.-400° C., obtaining the reaction of chloropentafluoroethane with pentafluoroethane with formation of hexafluoroethane (FC 116) and tetrafluorochloroethane (HCFC 124).
    Type: Grant
    Filed: July 17, 2000
    Date of Patent: January 28, 2003
    Assignee: Ausimont S.p.A.
    Inventors: Paolo Cuzzato, Sergio Peron
  • Patent number: 6500994
    Abstract: A process for purification of 1,1,1,3,3-pentafluorobutane (HFC-365mfc) containing a decreased amount of hydrogen chloride, hydrogen fluoride and/or unsaturated impurities. To this end crude 1,1,1,3,3-pentafluorobutane is treated in the liquid phase with a solid, inorganic sorption agent and/or with diatomic molecules which and to C—C multiple bonds. The product to be purified is preferably treated with elemental fluorine. The contents of hydrogen chloride and hydrogen can each be decreased to below 1 ppm. The content of unsaturated (chlorine)-fluorine-compounds can be decreased to below 20 ppm, and the content of unsaturated C2 compounds can be decreased to below 10 ppm. It has also been discovered that fluorotrichloroethylene can be used as a control substance to monitor the purification of 1,1,1,3,3-pentafluorobutane.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: December 31, 2002
    Assignee: Solvay Fluor und Derivate GmbH
    Inventors: Carsten Brosch, Heinz Gress, Matthias Rieland
  • Patent number: 6489277
    Abstract: In order to replace 1,1,2-trichloro-1,2,2-trifluoroethane and 1,1-dichloro-1-fluoroethane in compositions for treating solid surfaces (in particular defluxing), the invention proposes the use of a quasi-azeotropic mixture containing, by weight, from 75 to 95% of 1,1,1,3,3-pentafluorobutane, from 1 to 15% of methylene chloride and from 1 to 10% of methanol.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: December 3, 2002
    Assignee: Elf Atochem S.A.
    Inventor: Pascal Michaud
  • Patent number: 6489523
    Abstract: The present invention intends to provide a process for producing CF3CF3 with good profitability using CF3CHF2 containing a compound having chlorine atom within the molecule, and use thereof. In the process of the present invention, a gas mixture containing CF3CHF2 and a compound having chlorine atom within the molecule is reacted with hydrogen fluoride in the presence of a fluorination catalyst, thereby converting CClF2CF3 as a main impurity into CF3CF3, and CF3CHF2 containing CF3CF3 is reacted with fluorine gas in the gaseous phase in the presence of a diluting gas.
    Type: Grant
    Filed: January 14, 2002
    Date of Patent: December 3, 2002
    Assignee: Showa Denko K.K.
    Inventors: Hiromoto Ohno, Kazunari Kaga, Toshio Ohi
  • Publication number: 20020157938
    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: Application
    Filed: April 25, 2001
    Publication date: October 31, 2002
    Inventor: John A. Wismer
  • Publication number: 20020157940
    Abstract: A process for preparing purified, saturated, partially fluorinated or perfluorinated hydrocarbon compounds from crude products which are contaminated with impurity compounds which absorb light at a wavelength of &lgr;>200 nm by irradiating the crude product with UV radiation of a wavelength of &lgr;>200 nm and thereafter recovering highly pure, partially fluorinated or perfluorinated hydrocarbon compounds from the irradiated reaction product, for example, by simple vacuum distillation.
    Type: Application
    Filed: March 4, 2002
    Publication date: October 31, 2002
    Inventors: Max Braun, Carsten Brosch, Heinz Gress
  • Publication number: 20020156331
    Abstract: A process for recovery of hydrogen fluoride comprises contacting a gaseous mixture containing hydrogen fluoride and an organic compound 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 enriched in hydrogen fluoride, and then recovering the hydrogen fluoride from the liquid phase.
    Type: Application
    Filed: October 7, 1999
    Publication date: October 24, 2002
    Inventors: PAUL NICHOLAS EWING, CHARLES JOHN SHIELDS, ROBERT ELLIOTT LOW
  • Patent number: 6437202
    Abstract: A method for removing one or more fluorinated alkenes from a fluid comprises the step of contacting the fluid with an N-, S-, or P-containing nucleophile for a time sufficient to form an N-, S-, or P-containing nucleophile-fluoroalkene adduct. The nucleophile, and therefore the adduct, can be covalently bonded, coated or sorbed to a particulate support which can be enmeshed in a porous, fibrous web. In a preferred embodiment the fluorinated alkene can have the formula wherein A=F or Rf; X=H, F, Cl, Rf, or YRf; Z=H, F, Cl, or Rf; and Y=O, N, or S; with the proviso that at least one A=F, and at most one of Z and X is H; wherein each Rf is independently selected from the group consisting of highly fluorinated or perfluorinated alkyl groups; and a combination of any two Rf groups can be linked to form a cyclic structure. The Rf alkyl chains may contain from 1-20 carbon atoms, with 1-12 carbon atoms preferred.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: August 20, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Mark Eugene Mueller, Donald Frederick Hagen, Yuri Cheburkov, Fred Lynn DeRoos, Glenn Delmont Johnson, John Stephen Marhevka, Venkateswarlu Pothapragada
  • Patent number: 6437168
    Abstract: A method for efficiently extracting a reaction product containing a target aromatic fluorine compound formed by the halogen exchange reaction of an aromatic chlorine compound with a fluorinating agent quickly from the reaction vessel without suffering part of the reaction product to remain as a residue inside the reaction vessel is disclosed. Specifically, the reaction product is extracted from the reactor subsequently to the halogen exchange reaction at a temperature in the range of 20-250° C. By this method, the reaction product formed in consequence of the halogen exchange reaction can be efficiently extracted quickly from the reaction vessel, and that without suffering occurrence of a residue of the reaction product.
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: August 20, 2002
    Assignee: Nippon Shokubai Co., Ltd.
    Inventor: Kouichi Hirota
  • Patent number: 6414203
    Abstract: A method for reducing the content of unsaturated impurities contained in 1,1,1,3,3-pentafluoropropane (R245fa), while maintaining the loss of R245fa at a minimum level. R245fa containing unsaturated impurities is contacted in a gas phase with chlorine gas in the presence of an activated carbon catalyst, thereby converting the unsaturated impurities to the chlorine addition compounds to reduce the content of the unsaturated impurities.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: July 2, 2002
    Assignee: Asahi Glass Company, Limited
    Inventors: Hidekazu Okamoto, Keiichi Ohnishi
  • Publication number: 20020077513
    Abstract: In the synthesis of 1,1,1,3,3-pentafluorobutane (R-365mfc), a mixture of R-365mfc and the impurity 1-chloro-3,3,3-trifluoropropene (R-1354zd) is purified and R-1354zd is removed from the mixture by contacting the mixture with 1-5 mols of chlorine for each mol of R-1354zd in the presence of ultraviolet light having a wavelength between about 300 to 400 nm which provides at least 0.02 watts-hour/kg of the mixture. The R-1354zd is reduced to below 10 wt. ppm as it is converted to 2,3-dichloro-1,1,1,3-tetrafluorobutane (R-354) or other butane containing more chlorine and having a higher boiling point than R-365mfc. The butane(s) may be separated more easily from R-365mfc. The photochlorination is effected in a manner such that at least about 96 weight percent of the starting amount of R-365mfc is maintained in the mixture.
    Type: Application
    Filed: December 15, 2000
    Publication date: June 20, 2002
    Inventors: Stephen Frederic Yates, Hsueh Sung Tung
  • Patent number: 6403849
    Abstract: A method for obtaining purified perfluorocarbon compositions, and purified compositions containing such perfluorocarbons.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: June 11, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Zai-Ming Qiu, Zhongxing Zhang
  • Patent number: 6399841
    Abstract: Hydrogen fluoride is separated from its mixtures with 1,1,1,3,3-pentafluorobutane by extraction using an organic solvent containing a 1,1,1,3,3-chloro(fluoro)butane.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: June 4, 2002
    Assignee: Solvay (Societe Anonyme)
    Inventors: Alain Lambert, Vincent Wilmet
  • Patent number: 6395941
    Abstract: In order to remove the impurities (in particular 1-chloro-2,2-difluoroethylene) present in crude 1,1,1,2-tetrafluoroethane (F134a), a gaseous mixture of crude F134a and hydrofluoric acid is treated in the gas phase, in the presence of a fluorination catalyst, at a temperature of between 200 and 380° C. and under a pressure between atmospheric pressure and 2.5 MPa, the HF/F134a molar ratio being between 0.05 and 0.5.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: May 28, 2002
    Assignee: Elf Atochem, S.A.
    Inventors: Bernard Cheminal, Andre Lantz
  • Publication number: 20020040172
    Abstract: The invention relates to the purification of pentafluoroethane (F125) containing chloropentafluoroethane (F115) by liquid/liquid extraction or by extractive distillation.
    Type: Application
    Filed: June 26, 2001
    Publication date: April 4, 2002
    Inventors: Emmanuel Guiraud, Cathy Descamps
  • Publication number: 20020035300
    Abstract: A process is disclosed for producing the pentafluoropropenes of the formula CF 3 CX═CF 2 , where X is H or Cl. The process involves hydrodehalogenating CF 3 CCl 2 CF 3 with hydrogen at an elevated temperature in the vapor phase over a catalyst comprising an elemental metal, metal oxide, metal halide and/or metal oxyhalide (the metal being copper, nickel, chromium and the halogen of said halides and said oxyhalides being fluorine and/or chlorine).
    Type: Application
    Filed: August 19, 1999
    Publication date: March 21, 2002
    Inventors: V.N. MALLIKARJUNA RAO, ALLEN CAPRON SIEVERT
  • Publication number: 20020010373
    Abstract: The invention relates to a process for purifying a crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate containing an impurity. The process includes bringing the crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate into contact with a poor solvent in which 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate is substantially insoluble, thereby removing the impurity from the crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate. Alternatively, the process includes precipitating crystals of 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate from a solution of the crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate. Thus, it is possible to produce 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate of high purity. This product makes it easy to produce 1,1,1,5,5,5-hexafluoroacetylacetone of high purity.
    Type: Application
    Filed: December 21, 2000
    Publication date: January 24, 2002
    Inventors: Takeo Komata, Nariaki Ii, Yoshiki Hirotsu
  • Patent number: 6340781
    Abstract: A process for the removal of chloroalkane, chlorofluoroalkane and/or hydrofluoroalkane impurities from pentafluoroethane which comprises contacting the impure pentafluoroethane with hydrogen at elevated temperature in the presence of a hydrogenation catalyst to convert the impurity or impurities to a hydrofluoroalkane and/or a hydrocarbon and separating the resulting hydrofluoroalkane and/or hydrocarbon from the pentafluoroethane.
    Type: Grant
    Filed: April 3, 1995
    Date of Patent: January 22, 2002
    Assignee: Imperial Chemical Industries PLC
    Inventors: Charles John Shields, Gary Goodyear
  • Publication number: 20020007099
    Abstract: 1,1-Difluoroethane containing less than 10 mg/kg of vinyl chloride is obtained by treatment, with hydrogen fluoride, of a crude 1,1-difluoroethane containing less than 1 mol of hydrogen chloride per mole of 1,1-difluoroethane.
    Type: Application
    Filed: November 30, 1998
    Publication date: January 17, 2002
    Inventors: CHARLES-MARIE ANCIAUX, VINCENT WILMET, DOMINIQUE LECROC
  • Patent number: 6333440
    Abstract: A process is disclosed for obtaining octafluorocyclobutane of increased purity from a mixture comprising (a) octafluorocyclobutane and (b) at least one halocarbon impurity which is difficult to separate from octafluorocyclobutane by distillation (e.g., azeotropes of octafluorocyclobutane with such halocarbons). The process involves (1) contacting the mixture with a catalyst in the vapor phase in the presence HCl and/or HF at a temperature sufficient to react component (b) impurity with HCl and/or HF to provide a product mixture comprising halogenated product which is more easily separated from octafluorocyclobutane by distillation than the unreacted impurity; and (2) separating halogenated product obtained in (1) from octafluorocyclobutane by distillation.
    Type: Grant
    Filed: April 4, 2001
    Date of Patent: December 25, 2001
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: V. N. Malikarjuna
  • Patent number: 6328907
    Abstract: There is provided an azeotropic mixture consisting substantially of 1,1,1, 3,3-pentafluoropropane and hydrogen fluoride. Further, there is provided a process of separating/purifying R-245fa and/or HF from a mixture comprising R-245fa and HF wherein the mixture comprising 1,1,1,3,3-pentafluoropropane and hydrogen fluoride is subjected to a distillation step so that a distillate is obtained which comprises the azeotropic mixture consisting substantially of 1,1,1,3,3-pentafluoropropane and hydrogen fluoride, and a bottom product is obtained which comprises separated/purified 1,1,1,3,3-pentafluoropropane or hydrogen fluoride.
    Type: Grant
    Filed: July 23, 1998
    Date of Patent: December 11, 2001
    Assignee: Daikin Industries, Ltd.
    Inventors: Tatsuo Nakada, Noriaki Shibata, Takashi Shibanuma
  • Publication number: 20010047117
    Abstract: A method for removing one or more fluorinated alkenes from a fluid comprises the step of contacting the fluid with an N-, S-, or P-containing nucleophile for a time sufficient to form an N-, S-, or P-containing nucleophile-fluoroalkene adduct. The nucleophile, and therefore the adduct, can be covalently bonded, coated or sorbed to a particulate support which can be enmeshed in a porous, fibrous web.
    Type: Application
    Filed: June 13, 2001
    Publication date: November 29, 2001
    Applicant: 3M Innovative Properties Company
    Inventors: Mark Eugene Mueller, Donald Frederick Hagen, Yuri Cheburkov, Fred Lynn DeRoos, Glenn Delmont Johnson, John Stephen Marhevka, Venkateswarlu Pothapragada
  • Patent number: 6288294
    Abstract: A method for purifying a 133a product mixture containing olefinic impurities is provided wherein the mixture is contacted with a diene under conditions sufficient to convert the olefinic impurities to cyclohexenes.
    Type: Grant
    Filed: March 6, 2001
    Date of Patent: September 11, 2001
    Assignee: Atofina Chemicals, Inc.
    Inventor: Michael S. Bolmer