Purification Or Recovery Patents (Class 560/248)
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Patent number: 5466876Abstract: 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: GrantFiled: March 4, 1994Date of Patent: November 14, 1995Assignee: BP Chemicals LimitedInventors: Andrew R. McClarron, Stephen J. Smith, Derrick J. Watson, Bruce L. Williams, Euan S. Ross
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Patent number: 5434299Abstract: 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 separationType: GrantFiled: November 22, 1993Date of Patent: July 18, 1995Assignee: Daicel Chemical Industries, Ltd.Inventors: Masakazu Negawa, Fumihiko Shoji
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Patent number: 5434298Abstract: 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 separationType: GrantFiled: March 12, 1993Date of Patent: July 18, 1995Assignee: Daicel Chemical Industries, Ltd.Inventors: Masakazu Negawa, Fumihiko Shoji
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Patent number: 5399752Abstract: 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: GrantFiled: May 31, 1994Date of Patent: March 21, 1995Assignee: Eastman Chemical CompanyInventors: Stanley J. Okrasinski, Regina M. Moncier, Patricia N. Mercer, Dewey W. Fuller, Jr., Steven L. Cook
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Patent number: 5393385Abstract: 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: GrantFiled: March 14, 1994Date of Patent: February 28, 1995Assignee: Lloyd BergInventors: Lloyd Berg, Randi W. Wytcherley
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Patent number: 5356520Abstract: 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: GrantFiled: February 26, 1993Date of Patent: October 18, 1994Assignee: Mallinckrodt Medical PMCInventors: William Z. McCarthy, Michael J. Gentilcore
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Patent number: 5302746Abstract: 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: GrantFiled: April 12, 1993Date of Patent: April 12, 1994Assignee: Sumitomo Chemical Company, LimitedInventors: Seiji Koono, Osamu Moriya, Toshio Noguchi, Haruki Okamura
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Patent number: 5300685Abstract: 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: GrantFiled: November 25, 1991Date of Patent: April 5, 1994Assignee: Hoechst Celanese CorporationInventors: Mark O. Scates, R. Jay Warner, G. Paull Torrence
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Patent number: 5285006Abstract: 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: GrantFiled: June 26, 1992Date of Patent: February 8, 1994Assignee: Nalco Chemical CompanyInventors: Michael K. Poindexter, Vincent E. Lewis
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Patent number: 5277766Abstract: 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: GrantFiled: March 30, 1993Date of Patent: January 11, 1994Assignee: Lloyd BergInventor: Lloyd Berg
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Patent number: 5278334Abstract: 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: GrantFiled: October 1, 1992Date of Patent: January 11, 1994Assignee: Ethyl CorporationInventor: Ronny W. Lin
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Patent number: 5262014Abstract: 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: GrantFiled: June 12, 1992Date of Patent: November 16, 1993Assignee: The British Petroleum Company p.l.c.Inventors: Jeremy B. Cooper, John Dixon-Hall, Stephen J. Smith
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Patent number: 5258102Abstract: 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: GrantFiled: March 29, 1993Date of Patent: November 2, 1993Assignee: Lloyd BergInventor: Lloyd Berg
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Patent number: 5256259Abstract: 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: GrantFiled: March 29, 1993Date of Patent: October 26, 1993Assignee: Lloyd BergInventors: Lloyd Berg, Randi W. Wytcherley
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Patent number: 5240567Abstract: 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: GrantFiled: April 2, 1993Date of Patent: August 31, 1993Assignee: Lloyd BergInventors: Lloyd Berg, Randi W. Wytcherley
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Patent number: 5236559Abstract: 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: GrantFiled: January 22, 1993Date of Patent: August 17, 1993Assignee: Lloyd BergInventors: Lloyd Berg, Randi W. Wytcherley
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Patent number: 5235095Abstract: 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: GrantFiled: January 24, 1992Date of Patent: August 10, 1993Assignee: Ethyl CorporationInventors: Abbas Kadkhodayan, Deepak R. Patil, Azfar A. Choudhury
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Patent number: 5225050Abstract: 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: GrantFiled: December 15, 1992Date of Patent: July 6, 1993Assignee: Lloyd BergInventors: Lloyd Berg, Randi W. Wytcherley
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Patent number: 5220053Abstract: 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: GrantFiled: January 24, 1992Date of Patent: June 15, 1993Assignee: Ethyl CorporationInventors: Azfar A. Choudhury, Abbas Kadkhodayan, Deepak R. Patil
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Patent number: 5220058Abstract: 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: GrantFiled: September 30, 1991Date of Patent: June 15, 1993Assignee: Union Carbide Chemicals & Plastics Technology CorporationInventors: Barry B. Fish, William D. Prince, Michael P. Spratt
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Patent number: 5208258Abstract: 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: GrantFiled: April 17, 1990Date of Patent: May 4, 1993Assignee: The Regents of the University of CaliforniaInventors: Clayton H. Heathcock, Terry J. Rosen
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Patent number: 5208367Abstract: 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: GrantFiled: December 17, 1991Date of Patent: May 4, 1993Assignee: Exxon Chemical Patents Inc.Inventor: John D. Ou
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Patent number: 5206434Abstract: 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: GrantFiled: November 19, 1990Date of Patent: April 27, 1993Assignee: Hoechst Celanese CorporationInventors: Mark O. Scates, Russell K. Gibbs, Jr., G. Paull Torrence
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Patent number: 5202463Abstract: 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: GrantFiled: September 10, 1991Date of Patent: April 13, 1993Assignee: ARCO Chemical Technology, L.P.Inventor: Jude T. Ruszkay
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Patent number: 5175374Abstract: 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: GrantFiled: June 29, 1992Date of Patent: December 29, 1992Assignee: Shell Oil CompanyInventors: Rudolf J. Wijngaarden, Kees Latjes, Jan Van Schaik
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Patent number: 5169982Abstract: 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: GrantFiled: September 16, 1986Date of Patent: December 8, 1992Assignee: Hoechst AktiengesellschaftInventors: Erpenbach Heinz, Klaus Gehrmann, Peter Horstermann
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Patent number: 5149861Abstract: 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: GrantFiled: March 1, 1991Date of Patent: September 22, 1992Assignee: BASF AktiengesellschaftInventors: Franz Merger, Peter Hettinger, Leopold Hupfer, Juergen Paetsch, Heribert Deck, Heinz Auer, Erwin Brunner
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Patent number: 5143585Abstract: 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: GrantFiled: September 15, 1989Date of Patent: September 1, 1992Assignee: Konica CorporationInventors: Kazuyoshi Ichikawa, Shinichi Suzuki, Sanae Oyama, Hideaki Kimura
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Patent number: 5118838Abstract: 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: GrantFiled: June 27, 1991Date of Patent: June 2, 1992Assignee: Amoco CorporationInventors: Martin A. Zeitlin, David S. Hacker, Kristi A. Fjare, Diane J. Graziano, Stacey L. Kissinger
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Patent number: 5094724Abstract: 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: GrantFiled: April 19, 1991Date of Patent: March 10, 1992Assignee: Lloyd BergInventors: Lloyd Berg, Zuyin Yang
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Patent number: 5066365Abstract: 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: GrantFiled: October 15, 1990Date of Patent: November 19, 1991Assignee: Hoechst AktiengesellschaftInventors: Gunter Roscher, Karl-Heinz Schmidt, Klaus Eichler, Peter Horstermann, Reinhard Gradl, Horst Langner
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Patent number: 5059288Abstract: 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: GrantFiled: November 21, 1989Date of Patent: October 22, 1991Assignee: HarborchemInventor: William J. Curry
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Patent number: 5057192Abstract: 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: GrantFiled: February 28, 1991Date of Patent: October 15, 1991Assignee: Eastman Kodak CompanyInventors: Joseph R. Zoeller, Steven L. Cook, Charles E. Outlaw, Robert M. Schisla, Jr.
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Patent number: 4978430Abstract: 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: GrantFiled: July 24, 1989Date of Patent: December 18, 1990Assignee: UBE Industries, Ltd.Inventors: Kanji Nakagawa, Yoshio Asakura, Shigeru Yamamoto, Kohei Ninomiya, Masayuki Kinouchi
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Patent number: 4978778Abstract: 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: GrantFiled: December 13, 1983Date of Patent: December 18, 1990Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Tomiya Isshiki, Yasuhiko Kijima, Akiro Ito, Yuh Miyauchi, Takao Konko, Takayuki Watanabe
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Patent number: 4975155Abstract: 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: GrantFiled: September 19, 1989Date of Patent: December 4, 1990Assignee: BP Chemicals LimitedInventor: Benjamin P. Gracey
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Patent number: 4946029Abstract: 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: GrantFiled: February 24, 1989Date of Patent: August 7, 1990Assignee: BASF AktiengesellschaftInventors: Gerhard Frank, Hubert Lendle, Wilfried Seyfert, Peter Stops
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Patent number: 4942228Abstract: 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: GrantFiled: May 6, 1986Date of Patent: July 17, 1990Assignee: The Procter & Gamble CompanyInventor: Michael S. Gibson
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Patent number: 4939294Abstract: 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: GrantFiled: May 22, 1989Date of Patent: July 3, 1990Assignee: Eastman Kodak CompanyInventors: Victor H. Agreda, Ronnie D. Lilly
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Patent number: 4934519Abstract: 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: GrantFiled: June 28, 1985Date of Patent: June 19, 1990Assignee: Bayer AktiengesellschaftInventors: Gunter Wolf, Hubert Lauer, Wulf Schwerdtel
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Patent number: 4925533Abstract: 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: GrantFiled: March 6, 1989Date of Patent: May 15, 1990Assignee: Lloyd BergInventor: Lloyd Berg
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Patent number: 4921873Abstract: 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: GrantFiled: June 14, 1985Date of Patent: May 1, 1990Assignee: Harbor Branch Oceanographic Institution, Inc.Inventors: Tatsuo Higa, Kenneth M. Snader
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Patent number: 4908477Abstract: 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: GrantFiled: March 9, 1987Date of Patent: March 13, 1990Assignee: BASF AktiengesellschaftInventors: Horst Hartmann, Waldhelm Hochstein, Gerd Kaibel, Franz-Josef Mueller
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Patent number: 4902716Abstract: 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: GrantFiled: December 18, 1984Date of Patent: February 20, 1990Assignee: Harbor Branch Oceanographic Institutuion, Inc.Inventors: Tatsuo Higa, Kenneth M. Snader
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Patent number: 4902824Abstract: 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: GrantFiled: May 9, 1988Date of Patent: February 20, 1990Assignee: Nalco Chemical CompanyInventor: Allen R. Syrinek
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Patent number: 4897161Abstract: 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: GrantFiled: March 20, 1989Date of Patent: January 30, 1990Assignee: Lloyd BergInventors: Lloyd Berg, Marc W. Paffhausen
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Patent number: 4894475Abstract: 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: GrantFiled: December 28, 1987Date of Patent: January 16, 1990Assignee: Mitsui Petrochemical Industries, Ltd.Inventors: Hiroaki Tan, Koji Kato, Junichi Imuta, Noriaki Kihara
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Patent number: 4883906Abstract: 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: GrantFiled: November 25, 1987Date of Patent: November 28, 1989Assignee: Union Carbide CorporationInventors: John N. Argyropoulos, Edmond J. Derderian, Brian T. Keen, Timothy G. Bumgardner
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Patent number: RE34281Abstract: 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: GrantFiled: February 6, 1992Date of Patent: June 15, 1993Assignee: BP Chemicals LimitedInventor: Benjamin P. Gracey
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Patent number: RE35107Abstract: 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: GrantFiled: August 11, 1992Date of Patent: December 5, 1995Assignee: HarborchemInventor: William J. Curry