Purification Or Recovery Patents (Class 560/248)
  • Patent number: 5466876
    Abstract: Corrosion metal contaminants are removed from a liquid composition comprising a carboxylic acid and/or an anhydride thereof, a rhodium carbonylation catalyst, and a carbonylation catalyst co-promoter by using a chelating resin selective for the removal of corrosion metals rather than carbonylation catalyst and co-promoter.
    Type: Grant
    Filed: March 4, 1994
    Date of Patent: November 14, 1995
    Assignee: BP Chemicals Limited
    Inventors: Andrew R. McClarron, Stephen J. Smith, Derrick J. Watson, Bruce L. Williams, Euan S. Ross
  • Patent number: 5434299
    Abstract: A process for recovering and reusing a solvent and optical isomers characterized by using a simulated moving packed bed which comprises an inlet for an eluent, an outlet for an extract containing an optical isomer strongly adsorbable on the packing, an inlet for a liquid containing an optical isomer mixture and an outlet for a raffinate containing an optical isomer weakly adsorbable on the packing in this order in a packed bed column containing packings for optical resolution and arranged in a solvent circulation passage, and in which the inlets and the outlets are intermittently and successively moved in the direction of liquid flow in the packed bed; recovering the solvent and the optical isomer(s) from the resultant extract and/or raffinate; returning the recovered solvent into the solvent circulation passage; or when the solvent is not recovered, heating the extract or raffinate to racemize an undesired optical isomer and reusing the resultant solution containing a racemic modification for the separation
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: July 18, 1995
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Masakazu Negawa, Fumihiko Shoji
  • Patent number: 5434298
    Abstract: A process for recovering and reusing a solvent and optical isomers, characterized by using a simulated moving packed bed which comprises an inlet for an eluent, an outlet for an extract containing an optical isomer strongly adsorbable on the packing, an inlet for a liquid containing an optical isomer mixture and an outlet for a raffinate containing an optical isomer weakly adsorbable on the packing in this order in a packed bed column containing packings for optical resolution and arranged in a solvent circulation passage, and in which the inlets and the outlets are intermittently and successively moved in the direction of liquid flow in the packed bed; recovering the solvent and the optical isomer(s) from the resultant extract and/or raffinate; returning the recovered solvent into the solvent circulation passage; or when the solvent is not recovered, heating the extract or raffinate to racemize an undesired optical isomer and reusing the resultant solution containing a racemic modification for the separation
    Type: Grant
    Filed: March 12, 1993
    Date of Patent: July 18, 1995
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Masakazu Negawa, Fumihiko Shoji
  • Patent number: 5399752
    Abstract: Disclosed is a process for the purification of carboxyl streams such as product streams comprising one or more carboxyl compounds selected from carboxylic acids, carboxylic anhydrides and alkylidene dicarboxylates. The process provides a means for the reduction of the iodine content of carboxyl compound product streams which are contaminated with one or more iodine compounds.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: March 21, 1995
    Assignee: Eastman Chemical Company
    Inventors: Stanley J. Okrasinski, Regina M. Moncier, Patricia N. Mercer, Dewey W. Fuller, Jr., Steven L. Cook
  • Patent number: 5393385
    Abstract: Hexane is difficult to separate from vinyl acetate and/or methyl acrylate by conventional distillation or rectification because of the closeness of their boiling points. Hexane can be readily separated from vinyl acetate and/or methyl acrylate by extractive distillation. Effective agents are dimethylsulfoxide and dimethylformamide.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: February 28, 1995
    Assignee: Lloyd Berg
    Inventors: Lloyd Berg, Randi W. Wytcherley
  • Patent number: 5356520
    Abstract: A process for the separation of amyl acetate, a high boiling point solvent from various high boiling point corrosive impurities, namely, bromoethyl acetate, in an industrial setting to allow for reuse through continuous recycling thereof.
    Type: Grant
    Filed: February 26, 1993
    Date of Patent: October 18, 1994
    Assignee: Mallinckrodt Medical PMC
    Inventors: William Z. McCarthy, Michael J. Gentilcore
  • Patent number: 5302746
    Abstract: A process for producing a carboxylic acid ester which comprises reacting a carboxylic acid with an alcohol in the presence of an acid catalyst to produce a reaction solution and neutralizing the reaction solution, characterized by using a countercurrently contacting column for neutralization, into which the esterified reaction solution is introduced at the lower portion of the column, an aqueous strong alkaline solution at a middle portion and an aqueous weak alkaline solution at an upper portion, removing a neutralized oil phase containing the carboxylic acid ester from the top of the column and removing an aqueous phase from the bottom, thereby continuously neutralizing the reaction solution.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: April 12, 1994
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Seiji Koono, Osamu Moriya, Toshio Noguchi, Haruki Okamura
  • Patent number: 5300685
    Abstract: A method is provided for removing iodide compounds, particularly alkyl iodide compounds, from iodine-containing liquids, particularly carboxylic acids and anhydrides manufactured by the carbonylation of alcohols, ethers, esters, and the like in the presence of a rhodium catalyst and an alkali metal or alkaline earth metal salt, particularly a lithium salt, wherein the carboxylic acid or anhydride is contacted with a silver or mercury salt coordinated to a polymeric resin containing functional groups having the capability to quaternize with or form ionic salts with the alkyl halides.
    Type: Grant
    Filed: November 25, 1991
    Date of Patent: April 5, 1994
    Assignee: Hoechst Celanese Corporation
    Inventors: Mark O. Scates, R. Jay Warner, G. Paull Torrence
  • Patent number: 5285006
    Abstract: In a method for reducing the fouling of a compressor of a vinyl acetate production unit having a light ends stream feed, a hindered phenol is added to the compressor feed. The method retards the loss of compressor efficiency with run time and increases the run time before clean-out is required. The hindered phenol is added in a dosage amount effective for reducing the fouling of the compressor.
    Type: Grant
    Filed: June 26, 1992
    Date of Patent: February 8, 1994
    Assignee: Nalco Chemical Company
    Inventors: Michael K. Poindexter, Vincent E. Lewis
  • Patent number: 5277766
    Abstract: Heptane cannot be removed from heptane-vinyl acetate mixtures by distillation because of the minimum boiling azeotrope. Heptane can be readily removed from vinyl acetate by extractive distillation. Typical effective agents are dimethylsulfoxide, phenol, diisobutyl ketone and hexyl acetate.
    Type: Grant
    Filed: March 30, 1993
    Date of Patent: January 11, 1994
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5278334
    Abstract: A method for racemizing an optically active aliphatic carboxylic acid, or ester thereof, of the formula: ##STR1## where R.sub.1 is hydrogen or C.sub.1 to C.sub.6 linear or branched alkyl; R.sub.2, R.sub.3 and R.sub.4 are different and are hydrogen or C.sub.1 to C.sub.6 linear or branched alkyl, C.sub.1 to C.sub.6 linear or branched haloalkyl, aralkyl, cycloalkyl, alkyl substituted cycloalkyl, C.sub.6 to C.sub.10 aryl, C.sub.1 to C.sub.6 linear or branched alkoxy, C.sub.6 to C.sub.10 aryloxy, C.sub.1 to C.sub.6 alkylthio, C.sub.2 to C.sub.8 cycloalkylthio, C.sub.6 to C.sub.10 arylthio, C.sub.6 to C.sub.10 arylcarbonyl, C.sub.4 to C.sub.8 cycloalkenyl, trifluoromethyl, halo, C.sub.4 to C.sub.5 heteroaryl, C.sub.10 to C.sub.14 aryl, or biphenyl unsubstituted or substituted with methyl or halo, comprising heating said optically active carboxylic acid, ester or salt thereof at a temperature of from about 100.degree. C. to about 400.degree. C.
    Type: Grant
    Filed: October 1, 1992
    Date of Patent: January 11, 1994
    Assignee: Ethyl Corporation
    Inventor: Ronny W. Lin
  • Patent number: 5262014
    Abstract: A process for removing acetone from an acetone/methyl acetate/methyl iodide mixture utilizing extractive distillation with water being introduced to the distillation zone above the point of introduction of the mixture and acetic acid being introduced at or above the point of introduction of the mixture. In a preferred embodiment the mixture is subjected to an initial extraction with an aqueous extractant to remove most of the methyl iodide.The process is particularly applicable to removing acetone by-product in carbonylation processes for the production of acetic anhydride.
    Type: Grant
    Filed: June 12, 1992
    Date of Patent: November 16, 1993
    Assignee: The British Petroleum Company p.l.c.
    Inventors: Jeremy B. Cooper, John Dixon-Hall, Stephen J. Smith
  • Patent number: 5258102
    Abstract: Heptane cannot be separated from vinyl acetate by conventional distillation or rectification because of the minimum boiling azeotrope. Heptane can be readily separated from vinyl acetate by using azeotropic distillation. Typical examples of effective agents are methyl acetate, ethanol, ethyl formate or t-amyl methyl ether.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: November 2, 1993
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5256259
    Abstract: Hexane cannot be separated from vinyl acetate by conventional distillation or rectification because of the minimum boiling azeotrope. Hexane can be readily separated from vinyl acetate by using azeotropic distillation. Typical examples of effective agents are acetone, acetonitrile or methyl t-butyl ether.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: October 26, 1993
    Assignee: Lloyd Berg
    Inventors: Lloyd Berg, Randi W. Wytcherley
  • Patent number: 5240567
    Abstract: The separation of vinyl acetate from methyl acrylate by distillation is difficult because of the closeness of their boiling points. Vinyl acetate can be readily removed from methyl acrylate by extractive distillation. Typical effective agents are phenol, methoxyethanol and isobutyl vinyl ether.
    Type: Grant
    Filed: April 2, 1993
    Date of Patent: August 31, 1993
    Assignee: Lloyd Berg
    Inventors: Lloyd Berg, Randi W. Wytcherley
  • Patent number: 5236559
    Abstract: Hexane cannot be removed from hexane--vinyl acetate--methyl acrylate mixtures because of the ternary azeotrope. Hexane can be readily removed from hexane--vinyl acetate--methyl acrylate mixtures by extractive distillation. Typical effective agents are phenol, diethylene glycol methyl ether and 2-nitropropane.
    Type: Grant
    Filed: January 22, 1993
    Date of Patent: August 17, 1993
    Assignee: Lloyd Berg
    Inventors: Lloyd Berg, Randi W. Wytcherley
  • Patent number: 5235095
    Abstract: An improved process for the separation of enantiomers of a racemic mixture of certain aliphatic carboxylic acids or esters thereof is disclosed. The process involves: (i) forming a salt solution comprising said racemic mixture of a C.sub.1 to C.sub.6 linear or branched aliphatic carboxylic acid and an organic or inorganic base; (ii) treating said salt solution with one-half molar equivalent of a chiral organic nitrogenous base having a base strength no stronger than said organic or inorganic base; and (iii) precipitating from the reaction solution formed in step (ii) the less soluble diastereomeric salt, the improvement being adding to the salt solution of step (ii) an inert organic or inorganic base that is soluble in the salt solution.
    Type: Grant
    Filed: January 24, 1992
    Date of Patent: August 10, 1993
    Assignee: Ethyl Corporation
    Inventors: Abbas Kadkhodayan, Deepak R. Patil, Azfar A. Choudhury
  • Patent number: 5225050
    Abstract: Hexane cannot be removed from hexane - vinyl acetate mixtures by distillation because of the minimum boiling azeotrope. Hexane can be readily removed from vinyl acetate by extractive distillation. Typical effective agents are phenol, 1-nitropropane and benzyl alcohol.
    Type: Grant
    Filed: December 15, 1992
    Date of Patent: July 6, 1993
    Assignee: Lloyd Berg
    Inventors: Lloyd Berg, Randi W. Wytcherley
  • Patent number: 5220053
    Abstract: An improved process for the separation of enantiomers of a racemic mixture of certain aliphatic carboxylic acids or esters thereof is disclosed. The process involves adding a mixture of the aliphatic carboxylic acid to the material formed by: (i) forming a solution comprising said racemic mixture of a C.sub.1 to C.sub.6 linear or branched aliphatic carboxylic acid and an organic or inorganic solvent; (ii) treating said solution with a chiral organic nitrogenous base; (iii) precipitating from the reaction solution formed in step (ii) a crystalline material comprised of the less soluble diastereomeric salt. The solution is admixed with the crystalline material for a time sufficient to cause an increase in the amount of the less soluble diastereomeric salt in the crystalline material.
    Type: Grant
    Filed: January 24, 1992
    Date of Patent: June 15, 1993
    Assignee: Ethyl Corporation
    Inventors: Azfar A. Choudhury, Abbas Kadkhodayan, Deepak R. Patil
  • Patent number: 5220058
    Abstract: This invention relates tot he use of ion exchange resins having metal-exchanged thiol functional groups in removing iodide impurities from carboxylic acids and/or carboxylic acid anhydrides. More particularly, this invention provides a process for removing iodide impurities from liquid carboxylic acids and/or carboxylic acid anhydrides using ion exchange resins in which thiol functional groups have been exchanged with silver, palladium or mercury.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: June 15, 1993
    Assignee: Union Carbide Chemicals & Plastics Technology Corporation
    Inventors: Barry B. Fish, William D. Prince, Michael P. Spratt
  • Patent number: 5208258
    Abstract: A method of preparing compactin and mevinolin, ketoacid, enone, and glutarate analogs thereof, and related compounds. The compounds are prepared in substantially enantiomerically pure form using a structurally convergent synthesis. Total syntheses of (+)-compactin, (+)-mevinolin and related compounds are provided. Novel compounds are identified, several of which show significant anti-hypercholesterolemic activity.
    Type: Grant
    Filed: April 17, 1990
    Date of Patent: May 4, 1993
    Assignee: The Regents of the University of California
    Inventors: Clayton H. Heathcock, Terry J. Rosen
  • Patent number: 5208367
    Abstract: A two-step extraction method for the separation of vinyl acetate from a liquid mixture containing oxygenated compounds, paraffins and olefins, vinyl acetate, water, heavy oils, and other impurities, such as an anti-oxidant, is provided. The first step of the process extracts vinyl acetate and oxygenated compounds from the liquid mixture with a water wash. The paraffins, olefins, and heavy oils are insoluble in the water wash and are recovered as a waste stream from the wash. In a second step the vinyl acetate-rich water is distilled in a steam stripper column. Water is collected as the bottoms from the column and the overhead vapors are cooled by a condenser and collected in a separator tank. The separator tank liquids separate into an aqueous phase and a vinyl acetate phase. The aqueous phase is a waste stream. The vinyl acetate phase is recovered and may be used as a feedstock for polymerization or copolymerization reactions.
    Type: Grant
    Filed: December 17, 1991
    Date of Patent: May 4, 1993
    Assignee: Exxon Chemical Patents Inc.
    Inventor: John D. Ou
  • Patent number: 5206434
    Abstract: Esters such as methyl acetate which contain carbonyl impurities including aldehydes are purified by adding to the esters an amino compound which reacts with the carbonyls to form water soluble nitrogenous derivatives, separating an organic ester phase from an aqueous derivative phase, and distilling the ester phase to further remove heavier impurities. The formation of nitrile from the nitrogenous derivative is minimized by adding water to the distillation column or washing the aqueous bottoms from distillation with water to further remove the derivatives from any ester contained in the bottoms. The organic phase recovered from the bottoms can be recycled to the distillation to recover ester.
    Type: Grant
    Filed: November 19, 1990
    Date of Patent: April 27, 1993
    Assignee: Hoechst Celanese Corporation
    Inventors: Mark O. Scates, Russell K. Gibbs, Jr., G. Paull Torrence
  • Patent number: 5202463
    Abstract: An improved process for preparing and purifying glycol ether esters is disclosed. An azeotroping agent is included at a sufficiently low level to allow removal of the water of reaction, but also permit removal of by-products from esterification in the low-boiling component.
    Type: Grant
    Filed: September 10, 1991
    Date of Patent: April 13, 1993
    Assignee: ARCO Chemical Technology, L.P.
    Inventor: Jude T. Ruszkay
  • Patent number: 5175374
    Abstract: The invention relates to a process for the separation of colloidal barium phosphate or colloidal barium sodium phosphate, used as a heterogeneous catalyst in the alkoxylation of an active hydrogen containing organic compound, from the alkoxylated product, which process comprises contacting the alkoxylated product with an amount of water sufficient to break the colloidal state of the barium phosphate or barium sodium phosphate, and collecting the phosphate.
    Type: Grant
    Filed: June 29, 1992
    Date of Patent: December 29, 1992
    Assignee: Shell Oil Company
    Inventors: Rudolf J. Wijngaarden, Kees Latjes, Jan Van Schaik
  • Patent number: 5169982
    Abstract: Iodine and its compounds are separated from the carbonylation products acetic acid, acetic anhydride or ethylidene diacetate obtained on subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction in the presence of an iodine-containing catalyst. The quantity of total iodine contaminating the carbonylation products is reduced to less than 20 ppb iodine by treating the products at 20.degree.-200.degree. C. with peracetic acid, diacetyl peroxide or a compound yielding these two agents under the reaction conditions, and separating them distillatively.
    Type: Grant
    Filed: September 16, 1986
    Date of Patent: December 8, 1992
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Erpenbach Heinz, Klaus Gehrmann, Peter Horstermann
  • Patent number: 5149861
    Abstract: Trialkylamines and methyl formate are recovered from reaction mixtures obtained in the preparation of trimethylolalkanes by reaction of n-alkanals with from 2.2 to 4.5 moles of formaldehyde in aqueous solution in the presence of from 0.6 to 3 mole of trialkylamine, each quantity based on 1 mole of alkanal, and subsequent hydrogenation in a process wherein the crude reaction mixturea) is heated to from 100.degree. to 200.degree. C.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: September 22, 1992
    Assignee: BASF Aktiengesellschaft
    Inventors: Franz Merger, Peter Hettinger, Leopold Hupfer, Juergen Paetsch, Heribert Deck, Heinz Auer, Erwin Brunner
  • Patent number: 5143585
    Abstract: An organic solvent having a boiling point lower than that of water is removed from liquid containig water and the organic solvent contained in a tank by exhausting air in the tank, wherein an air pressure in the tank is kept about vapor pressure level of the liquid.
    Type: Grant
    Filed: September 15, 1989
    Date of Patent: September 1, 1992
    Assignee: Konica Corporation
    Inventors: Kazuyoshi Ichikawa, Shinichi Suzuki, Sanae Oyama, Hideaki Kimura
  • Patent number: 5118838
    Abstract: Substantial proportions of methyl acetate and unreacted polymethylbenzene are recovered from the waste gas produced during the oxidation of a polymethylbenzene to its corresponding polycarboxylic acid by passing the waste gas, after being cooled for removal of water vapor, through at least one bed of activated carbon and subsequently desorbing the methyl acetate and polymethylbenzene from the bed by passing a desorbing medium, such as steam, through the bed. Preferably, the cooled stream is heated to a temperature of at least 21.degree. C. (70.degree. F.) prior to being passed into the bed of activated carbon.There is also disclosed an improved process for the oxidation of a polymethylbenzene to its corresponding aromatic polycarboxylic acid, which process comprises producing the polycarboxylic acid and waste gas comprising methyl acetate, water vapor, and unreacted polymethylbenzene and treating the waste gas according to the above method.
    Type: Grant
    Filed: June 27, 1991
    Date of Patent: June 2, 1992
    Assignee: Amoco Corporation
    Inventors: Martin A. Zeitlin, David S. Hacker, Kristi A. Fjare, Diane J. Graziano, Stacey L. Kissinger
  • Patent number: 5094724
    Abstract: Methylene chloride cannot be completely separated from methyl formate or ethyl formate by conventional distillation or rectification because of the minimum boiling azeotrope. Methylene chloride can be readily separated from methyl formate or ethyl formate by extractive distillation. Typical effective agents are: for methyl formate, n-butyl acetate and 3-hexanone; for ethyl formate, isobornyl acetate and 2-heptanone.
    Type: Grant
    Filed: April 19, 1991
    Date of Patent: March 10, 1992
    Assignee: Lloyd Berg
    Inventors: Lloyd Berg, Zuyin Yang
  • Patent number: 5066365
    Abstract: The invention relates to a process for the isolation of vinyl acetate which involves not combining the bottom product of the recylced gas washings with the water-saturated vinyl acetate but rather introducing it to further multiple distillation columns from the gas mixture formed in the reaction of ethylene with acetic acid and oxygen over catalysts containing palladium or palladium compounds in the gas phase.
    Type: Grant
    Filed: October 15, 1990
    Date of Patent: November 19, 1991
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunter Roscher, Karl-Heinz Schmidt, Klaus Eichler, Peter Horstermann, Reinhard Gradl, Horst Langner
  • Patent number: 5059288
    Abstract: High purity isopropyl acetate and ethanol are recovered from a process stream containing isopropyl acetate, ethanol and water by a multiple step process including extracting substantially all of the ethanol from the stream using water as a solvent, stripping the extract stream to remove substantially all of the remaining isopropyl acetate as an overhead recycle stream, which is combined with the fresh feed stream prior to the extraction step, fractionating the ethanol-rich stripping column bottoms stream to produce a ethanol-water azeotropic overhead stream and using a portion of the fractionating column bottoms stream as the solvent for the extraction step.
    Type: Grant
    Filed: November 21, 1989
    Date of Patent: October 22, 1991
    Assignee: Harborchem
    Inventor: William J. Curry
  • Patent number: 5057192
    Abstract: Disclosed is an improved process for the removal of acetone from a production system wherein acetic anhydride is produced by contacting a mixture containing methyl iodide and methyl acetate and/or dimethyl ether with carbon monoxide in the presence of a carbonylation catalyst or catalyst system. The process involves a water-methyl iodide extraction step wherein acetone is separated from a mixture of methyl acetate, methyl iodide and acetone.
    Type: Grant
    Filed: February 28, 1991
    Date of Patent: October 15, 1991
    Assignee: Eastman Kodak Company
    Inventors: Joseph R. Zoeller, Steven L. Cook, Charles E. Outlaw, Robert M. Schisla, Jr.
  • Patent number: 4978430
    Abstract: An improved method for dehydration and concentration of an aqueous solution containing an organic compound is disclosed. The solution is evaporated to produce a gaseous mixture comprising an organic compound vapor and a water vapor. The water vapor is selectively removed from the gaseous mixture by permeation through an aromatic polyimide gas separation membrane while the gaseous mixture being kept in contact with a surface on one side of the gas separation membrane at a temperature of 70.degree. C. or higher to obtain a gaseous mixture comprising the organic compound vapor and a reduced amount of a water vapor.
    Type: Grant
    Filed: July 24, 1989
    Date of Patent: December 18, 1990
    Assignee: UBE Industries, Ltd.
    Inventors: Kanji Nakagawa, Yoshio Asakura, Shigeru Yamamoto, Kohei Ninomiya, Masayuki Kinouchi
  • Patent number: 4978778
    Abstract: A process for producing vinyl acetate which comprises reacting acetic anhydride with hydrogen in the presence of a catalyst comprising(a) a metal belonging to Group VIII of the Periodic Table or a compound of the metal, and(b) (i) an acidic substance, or (ii) a halideis disclosed.
    Type: Grant
    Filed: December 13, 1983
    Date of Patent: December 18, 1990
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Tomiya Isshiki, Yasuhiko Kijima, Akiro Ito, Yuh Miyauchi, Takao Konko, Takayuki Watanabe
  • Patent number: 4975155
    Abstract: A process for removing iodine or soluble iodide impurities from a carboxylic acid or carboxylic acid anhydride, the carboxylic acid or carboxylic acid anhydride having been by a carbonylation process. The process includes: step (a) treating impure carboxylic acid or carboxylic acid anhydride containing iodine or soluble iodide impurities with an unsupported scavenger at a temperature of between 20.degree. and 250.degree. C. and step (b) thereafter separating the treated carboxylic acid or carboxylic acid anhydride from the scavenger. The scavenger is a silver salt in the absence of a trialkyl phosphine, a triaryl phosphine and a heterocyclic aromatic nitrogen compound. The preferred scavenger for acetic acid and acetic anhydride is silver acetate.
    Type: Grant
    Filed: September 19, 1989
    Date of Patent: December 4, 1990
    Assignee: BP Chemicals Limited
    Inventor: Benjamin P. Gracey
  • Patent number: 4946029
    Abstract: Carboxylic esters obtained by reacting olefinically unsaturated compounds with carbon monoxide and alcohols and containing aldehydes, acetals and/or unsaturated compounds are purified by(a) treating the carboxylic ester which contains an aldehyde, acetal or unsaturated compound in a first stage at from 20.degree. to 200.degree. C. with a strongly acidic agent and(b) hydrogenating the mixture thus treated in a second stage at from 50.degree. to 200.degree. C. under a pressure of from 1 to 50 bar in the presence of one or more metals of subgroup VIII of the periodic table and(c) removing low and high boilers from the hydrogenated mixture obtained in stage b by distillation and obtaining a pure carboxylic ester.
    Type: Grant
    Filed: February 24, 1989
    Date of Patent: August 7, 1990
    Assignee: BASF Aktiengesellschaft
    Inventors: Gerhard Frank, Hubert Lendle, Wilfried Seyfert, Peter Stops
  • Patent number: 4942228
    Abstract: Polyol polyesters having reduced color content are prepared by base-catalyzed transesterification of pretreated lower (i.e., C.sub.1 -C.sub.3) alkyl fatty esters with polyols. The pretreatment comprises the steps of contacting the alkyl fatty esters (in a liquid state) with an alkoxide base, separating undissolved solids from the esters, and then distilling the esters.
    Type: Grant
    Filed: May 6, 1986
    Date of Patent: July 17, 1990
    Assignee: The Procter & Gamble Company
    Inventor: Michael S. Gibson
  • Patent number: 4939294
    Abstract: In a process for the production of methyl acetate from methanol and glacial acetic acid involving countercurrently flowing acetic acid and methanol through a single reactive distillation column having an extractive distillation section and a methyl acetate/acetic acid rectification section to obtain methyl acetate in the presence of an acidic catalyst, the improvement which comprises producing ultra high purity methyl acetate by the additional step of introducing acetic anhydride and a salt-free acid catalyst into the reactive distillation column between the extractive distillation section and the methyl acetate/acetic acid rectification section.
    Type: Grant
    Filed: May 22, 1989
    Date of Patent: July 3, 1990
    Assignee: Eastman Kodak Company
    Inventors: Victor H. Agreda, Ronnie D. Lilly
  • Patent number: 4934519
    Abstract: An improved process for working-up crude liquid vinyl acetate which contains vinyl acetate, acetic acid, water, and ethyl acetate, possibly together with small amounts of other impurities, by distillation is disclosed, wherein a mixture essentially containing vinyl acetate and water is obtained as the top product and essentially acetic acid is obtained as the bottom product, and a sidestream, in which ethyl acetate is concentrated is removed. According to the process the top product is condensed and, after phase separation, a portion of the vinyl acetate phase is recycled as reflux into the distillation. The improved process involves the introduction of water above the point of introduction of the crude vinyl acetate. Preferably, the water is introduced in an amount which is not greater than the amount required to achieve a maximum water content in the vapors leaving the distillation at the top.
    Type: Grant
    Filed: June 28, 1985
    Date of Patent: June 19, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gunter Wolf, Hubert Lauer, Wulf Schwerdtel
  • Patent number: 4925533
    Abstract: Vinyl acetate cannot be easily removed from ethyl acetate by distillation because of the closeness of their boiling points. Vinyl acetate can be readily separated from ethyl acetate by means of extractive distillation. Typical effective agents are formic acid, formamide and formic acid-formamide mixture.
    Type: Grant
    Filed: March 6, 1989
    Date of Patent: May 15, 1990
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 4921873
    Abstract: This invention relates to antiviral and antitumor compositions, a process for producing the compositions and a method for inhibiting viruses and tumors utilizing the compositions. More particularly, the compositions are cyclohexadienone derivatives which are derived from red alga Desmia hornemanni.
    Type: Grant
    Filed: June 14, 1985
    Date of Patent: May 1, 1990
    Assignee: Harbor Branch Oceanographic Institution, Inc.
    Inventors: Tatsuo Higa, Kenneth M. Snader
  • Patent number: 4908477
    Abstract: Organic iodine compounds are separated from carbonylation products of methanol, methyl acetate and dimethyl ether and from mixtures of such carbonylation products by a process wherein the iodine compounds are removed by liquid phase extraction with a non-aromatic hydrocarbon.
    Type: Grant
    Filed: March 9, 1987
    Date of Patent: March 13, 1990
    Assignee: BASF Aktiengesellschaft
    Inventors: Horst Hartmann, Waldhelm Hochstein, Gerd Kaibel, Franz-Josef Mueller
  • Patent number: 4902716
    Abstract: This invention relates to antiviral compositions, a process for producing the compositions and a method for inhibiting viruses utilizing the compositions. More particularly, the compositions are halogenated chamigrenes extracted from sea hares which diet upon red algae.
    Type: Grant
    Filed: December 18, 1984
    Date of Patent: February 20, 1990
    Assignee: Harbor Branch Oceanographic Institutuion, Inc.
    Inventors: Tatsuo Higa, Kenneth M. Snader
  • Patent number: 4902824
    Abstract: A dispersant for vinyl acetate process streams has been found, which dispersant acts as an antifoulant, preventing formation of fouling tars, polymers, debris, and the like, in the process streams involved in the manufacture of vinyl acetate monomer. The antifoulant/dispersant is primarily composed of hydrocarbonaceous sulfonic acids which may optionally be admixed organic polar solvents and tall oil fatty acids.
    Type: Grant
    Filed: May 9, 1988
    Date of Patent: February 20, 1990
    Assignee: Nalco Chemical Company
    Inventor: Allen R. Syrinek
  • Patent number: 4897161
    Abstract: Vinyl acetate cannot be easily removed from ethyl acetate by distillation because of the closeness of their boiling points. Vinyl acetate can be readily separated from ethyl acetate by means of extractive distillation using certain glycols or glycol ethers. Typical effective agents are 2-methyl -2,4-pentanediol, 1,3-butanediol, ethylene glycol methyl ether and diethylene glycol ethyl ether.
    Type: Grant
    Filed: March 20, 1989
    Date of Patent: January 30, 1990
    Assignee: Lloyd Berg
    Inventors: Lloyd Berg, Marc W. Paffhausen
  • Patent number: 4894475
    Abstract: Disclosed are alpha-acyloxyketone derivatives which are useful as intermediates for production of N-cyano-N'-methyl-N"-[2-{(5-methyl-1H-imidazol-4-yl)methylthio}ethyl]guani dine (common name: Cimetidine; Cimetidine applies hereinafter) and Cimetidine-related compounds which have an action of controlling secretion of gastric acid and are useful as a drug for treating gastric ulcer.
    Type: Grant
    Filed: December 28, 1987
    Date of Patent: January 16, 1990
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Hiroaki Tan, Koji Kato, Junichi Imuta, Noriaki Kihara
  • Patent number: 4883906
    Abstract: A process for producing and refining trisubstituted glycol monoesters, e.g., 2,2,4-trimethyl-1,3-pentanediol monoester. The improvement resides in immediately distilling the crude condensation product mixture as it leaves the reactor before it has cooled or had any contact with added water.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: November 28, 1989
    Assignee: Union Carbide Corporation
    Inventors: John N. Argyropoulos, Edmond J. Derderian, Brian T. Keen, Timothy G. Bumgardner
  • Patent number: RE34281
    Abstract: A process for removing iodine or soluble iodide impurities from a carboxylic acid or carboxylic acid anhydride, the carboxylic acid or carboxylic acid anhydride having been by a carbonylation process. The process includes: step (a) treating impure carboxylic acid or carboxylic acid anhydride containing iodine or soluble iodide impurities with an unsupported scavenger at a temperature of between 20.degree. and 250.degree. C. and step (b) thereafter separating the treated carboxylic acid or carboxylic acid anhydride from the scavenger. The scavenger is a silver salt in the absence of a trialkyl phosphine, a triaryl phosphine and a heterocyclic aromatic nitrogen compound. The preferred scavenger for acetic acid and acetic anhydride is silver acetate.
    Type: Grant
    Filed: February 6, 1992
    Date of Patent: June 15, 1993
    Assignee: BP Chemicals Limited
    Inventor: Benjamin P. Gracey
  • Patent number: RE35107
    Abstract: High purity isopropyl acetate and ethanol are recovered from a process stream containing isopropyl acetate, ethanol and water by a multiple step process including extracting substantially all of the ethanol from the stream using water as a solvent, stripping the extract stream to remove substantially all of the remaining isopropyl acetate as an overhead recycle stream, which is combined with the fresh feed stream prior to the extraction step, fractionating the ethanol-rich stripping column bottoms stream to produce a ethanol-water azeotropic overhead stream and using a portion of the fractionating column bottoms stream as the solvent for the extraction step.
    Type: Grant
    Filed: August 11, 1992
    Date of Patent: December 5, 1995
    Assignee: Harborchem
    Inventor: William J. Curry