Purification Or Recovery Patents (Class 564/216)
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Patent number: 5856575Abstract: This invention provides a process for the manufacture of N-acetyl amino phenol, which process comprises reacting an appropriate phenol and an amide in the presence of a heteropoly acid or its alkali metal salt catalyst.Type: GrantFiled: January 22, 1997Date of Patent: January 5, 1999Assignee: Council of Scientific Industrial ResearchInventors: Sarada Gopinathan, Changaramponnath Gopinathan, Joseph Kuruvilla, Sanjeevani Amrit Pardhy, Paul Ratnasamy
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Patent number: 5684199Abstract: The present invention is directed to a process for preparing formoterol and related compounds and derivatives thereof and their pharmacologically and pharmaceutically acceptable fumarate salts and/or solvates. The present invention is also directed to certain formoterol related compounds per se.Type: GrantFiled: June 13, 1996Date of Patent: November 4, 1997Assignee: Novartis CorporationInventor: Eric Francotte
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Patent number: 5599986Abstract: The present invention relates to a novel process for preparing alkali metal salts of diformylamide and a novel crystalline form of sodium diformylamide.Type: GrantFiled: August 31, 1995Date of Patent: February 4, 1997Assignee: Hoechst Marion Roussel Inc.Inventors: Jonathan C. Evans, Christian T. Goralski, Cynthia L. Rand, Paul C. Vosejpka
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Patent number: 5504239Abstract: A first alkanol having from 1 to 3 carbon atoms can be separated off from other organic compounds of higher carbon number from the group comprising other alcohols, polyalcohols, ethers, oxo compounds, esters of carboxylic acids and of carbonic acid, haloaliphatics, amines, amides, hydrocarbons, carboxylic acids and nitriles, which in each case have at least 1 carbon atom more than the first alkanol, where in the case of halogenoaliphatics, halogen substituents are counted as further carbon atoms, by permeation on membranes, if a water content from 1 to 30% by weight, preferably from 5 to 15% by weight, based on the amount of mixture and water, is maintained.Type: GrantFiled: June 7, 1994Date of Patent: April 2, 1996Assignee: Bayer AktiengesellschaftInventors: Wolf Mehl, Wolfgang Scheinert, Ingo Janisch, Andreas Groschl
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Patent number: 5399760Abstract: A method is provided for purifying crude N-acetyl-para-aminophenol (APAP) containing color bodies or their precursors, the method comprising: a) forming a solution of the crude APAP; and b) subsequently contacting the solution with substoichiometric quantifies of an acetylating agent for a sufficient period of time to convert said color bodies or their precursors to substantially non-color bodies/stable, colorless substances; said quantities of acetylating agent provided is such that substantially none of the APAP is converted to other compounds.Type: GrantFiled: August 11, 1993Date of Patent: March 21, 1995Assignee: Hoechst Celanese CorporationInventors: Edward G. Zey, Olan S. Fruchey, Thomas H. Shockley, Joe S. Trevino, B. Frank Wood, Daniel D. Lindley
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Patent number: 5344979Abstract: A method is provided for purifying a crude N-acetyl-para-aminophenol (APAP) containing color bodies or their precursors, the method comprising: a) forming a wet crude APAP; and b) subsequently drying said crude APAP in the presence of a sufficient amount of an acetylating agent for a sufficient period of time to convert said color bodies or their precursors to substantially non-color bodies.Type: GrantFiled: April 29, 1993Date of Patent: September 6, 1994Assignee: Hoechst Celanese CorporationInventors: Edward G. Zey, George A. Blay
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Patent number: 5254684Abstract: A process for producing an amide which comprises subjecting an oxime to liquid phase rearrangement in the presence of phosphorus pentoxide and at least one compound selected from the group consisting of N,N-dialkyl amides, N-alkyl cyclic amides and dialkyl sulfoxides and optionally a fluorine-containing strong said or its derivative. Said process can rearrange an oxime to a corresponding amide in a good yield under mild reaction conditions in the presence of a less stoichiometric amount of a catalyst.Type: GrantFiled: May 19, 1992Date of Patent: October 19, 1993Assignees: Sumitomo Chemical Company, Limited, Yusuke IzumiInventors: Yusuke Izumi, Hiroshi Sato, Hiroshi Yoshioka, Yoshisaburou Nomura
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Patent number: 5225547Abstract: A reaction accelerator for rearrangement of an oxime to an amide consisting of an alkylating agent and an N,N-disubstituted formamide or N,N-disubstituted carboxylic acid amide represented by formula (1): ##STR1## wherein R.sup.1 and R.sup.2, which may be the same or different, represent alkyl groups having 1 to 6 carbon atoms or substituted or unsubstituted phenyl groups having 6 to 9 carbon atoms, and R.sup.3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. An amide can effectively be produced by rearranging a corresponding oxime in the presence of said reaction accelerator.Type: GrantFiled: June 14, 1991Date of Patent: July 6, 1993Assignees: Sumitomo Chemical Company Limited, Yusuke IzumiInventor: Yusuke Izumi
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Patent number: 5221769Abstract: p-Aminophenyl acetate is isomerized to p-acetylaminophenol in the presence of an acid such as acetic acid or phosphoric acid.Type: GrantFiled: December 27, 1990Date of Patent: June 22, 1993Assignee: Mitsui Toatsu Chemicals Inc.Inventors: Hideyuki Akieda, Naoki Sato, Ryuichi Mita, Mitsumasa Umemoto
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Patent number: 5155269Abstract: A process for removing impurities from an aqueous feed mixture comprising a reaction solution produced by catalytic hydrogenation of nitrobenzene in an acid aqueous medium. An aqueous feed mixture comprising the reaction solution is contacted with an extractant comprising aniline for extraction from the feed mixture of 4,4'-diaminodiphenylether, thereby providing a primary raffinate that contains p-aminophenol and is contaminated with aniline. The primary raffinate is contacted at a pH of between about 5.5 and about 8.0 with a purifying solvent, the purifying solvent comprising an organic solvent effective for extraction of aniline from the primary raffinate, thereby producing a purified raffinate comprising p-aminophenol.Also described is a unified process for the preparation of N-acetyl-p-aminophenol in which p-aminophenol contained in the aforesaid purified raffinate is acetylated without prior separation of solid p-aminophenol from the raffinate.Type: GrantFiled: May 24, 1989Date of Patent: October 13, 1992Assignee: MallinckrodtInventors: Thomas J. Dunn, Vojko B. Jovanovic
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Patent number: 4996322Abstract: Amides having different molecular kinetic diameters or heats of adsorption, such as formamide and N-(1-alkoxyethyl)formamide, are separated under mild conditions with a molecular sieve which selectively adsorbs one of the amides, such as formamide. N-vinylformamide can be purified by removing formamide remaining in synthesis process streams using this technique. The adsorbed amide can be desorbed by heating the molecular sieve in either inert or reactive atmospheres. Preferred molecular sieves include the zeolites of types A, X, Y, molecular sieves of the MFI topology, chabazite, and mordenite. Calcium chabazite is particularly versatile and effective.Type: GrantFiled: May 15, 1989Date of Patent: February 26, 1991Assignee: Air Products and Chemicals, Inc.Inventors: Ronald Pierantozzi, Mildred A. Miller, Mark L. Listemann, Thomas R. Gaffney, Charles G. Coe
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Patent number: 4980031Abstract: Hydrogen chloride evolution is reduced in the distillation of chloroform from its admixture with an amide solvent when in contact with stainless steel, by incorporation of certain tertiary aliphatic amines.Type: GrantFiled: February 6, 1990Date of Patent: December 25, 1990Assignee: E. I. Du Pont de Nemours and CompanyInventor: David J. Rodini
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Patent number: 4814505Abstract: N-Vinylformamide is purified by fractional distillation in the presence of formamide in a column under from 0.5 to 30 mbar by a method in which the distillation is controlled so that N-vinylformamide containing from 0.1 to 15% by weight of formamide is obtained as the distillate. Homopolymers having particularly high molecular weights can be prepared from the N-vinylformamide purified in this manner.Type: GrantFiled: January 29, 1987Date of Patent: March 21, 1989Assignee: Basf AktiengesellschaftInventors: Michael Kroener, Willi Schmidt, Alfred Oftring, Theo Proll, Heinrich Hartmann
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Patent number: 4565890Abstract: An improved process for the preparation of N-acetyl-p-aminophenol. p-Aminophenol is acetylated in an aqueous medium to produce a crude aqueous reaction mixture and N-acetyl-p-aminophenol product is recovered by crystallization from an aqueous system comprising the reaction mixture. Crystals are separated from the crude mother liquor which contains residual N-acetyl-p-aminophenol and unreacted acetic acid. According to the improvement, residual N-acetyl-p-aminophenol and acetic acid are recovered from the crude mother liquor by liquid-liquid extraction with a water-immiscible organic solvent to produce an extract containing N-acetyl-p-aminophenol and acetic acid. The extract is distilled to strip off the solvent and acetic acid.Type: GrantFiled: October 27, 1983Date of Patent: January 21, 1986Assignee: Mallinckrodt, Inc.Inventor: Sharad S. Sathe
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Patent number: 4540815Abstract: Process for the preparation of pure 3-acetylaminoanilines of the general formula (1) ##STR1## in which R denotes a hydrogen atom or an alkoxy group with 1-4 carbon atoms, by reduction of 1,3-dinitrobenzene in an alkanol with 1-4 carbon atoms to the 1,3-diaminobenzene or by reaction of 2,4-dinitrochlorobenzene with sodium hydroxide in an alkanol with 1-4 carbon atoms and subsequent reduction to the 2,4-diaminoalkoxybenzene, and in each case subsequent monoacetylation in the alkanol mentioned to give the 1-amino-3-acetylamino-benzene or the 2-amino-4-acetylamino-alkoxy-benzene and isolation of the compound of the above formula (1) obtained in the alkanolic solution, which optionally contains water, which comprises carrying out the isolation by precipitation of the compound of the above formula (1), in the form of the hydrohalide, from the alkanolic solution by means of hydrogen halide or aqueous hydrogen halide acid and subsequent filtration.Type: GrantFiled: November 16, 1984Date of Patent: September 10, 1985Assignee: Hoechst AktiengesellschaftInventors: Theodor Papenfuhs, Manfred Hintzmann
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Patent number: 4501902Abstract: A process for removing compounds from aprotic solvents in which aprotic solvent containing at least one acidic compound is contacted with a solid inorganic compound chosen from alkaline earth carbonates, alkaline earth hydroxides, alkaline earth oxides, and alumina in which the contact of the solvent with a solid inorganic compound is by the process of fluidized bed contact, stirred slurry contact or trickle bed contact. Contaminated NMP from poly(phenylene sulfide) production is substantially freed of acidic contaminants by a series of fractionations with a treatment of the kettle liquid of at least one fractionation by the method described above and/or a treatment of the overhead of the last fractionation in series by the method described above.Type: GrantFiled: December 21, 1982Date of Patent: February 26, 1985Assignee: Phillips Petroleum CompanyInventor: James W. Cleary
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Patent number: 4474985Abstract: A process for increasing the color-free shelf life of a crude N-acetyl aminophenol prepared by the acetylation of an aminophenol wherein the N-acetyl aminophenol contains color-forming impurities which are the products of oxidation of the aminophenol and other side reactions. The process comprises dissolving the crude N-acetyl aminophenol in a solvent containing a reducing agent, heating the solution at about the boiling point, crystallizing the N-acetyl aminophenol from the solution, washing the crystalline N-acetyl aminophenol with solvent containing reducing agent and thereafter separating and drying the crystalline N-acetyl aminophenol.Type: GrantFiled: January 31, 1983Date of Patent: October 2, 1984Assignee: Monsanto CompanyInventors: Billy L. Keel, Irvin S. Klaus, Marvin L. Oftedahl
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Patent number: 4452994Abstract: An improved process for isolating organic compounds from crude product or reaction mixtures by dissolving said crude product or reaction mixture in a suitable solvent, contacting the resulting solution with a lithium salt to form a solid metal salt complex, separating, and thereafter recovering a pure product by decomposing the lithium salt complex.Type: GrantFiled: March 2, 1981Date of Patent: June 5, 1984Assignee: G. D. Searle & Co.Inventors: John B. Hill, Robert A. Erickson
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Patent number: 4420612Abstract: A catalyst membrane including a porous polytetrafluoroethylene membrane having grafted thereon polystyrenesulfonic acid. The catalyst membrane is useful for hydrolyzing water soluble organic substances such as polysaccharides.Type: GrantFiled: February 28, 1983Date of Patent: December 13, 1983Assignee: Director Genereal of Agency of Industrial Science & TechnologyInventors: Seiichi Aiba, Kazuhisa Hiratani, Tsutomu Nakagawa
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Patent number: 4401516Abstract: Acetamidoethylene is isolated from acetamidoethylene-containing mixtures by distillation with enhanced efficiency when a high-boiling liquid, especially glycerol, is added to the mixtures prior to or during said distillation. This invention is particularly effective at separating acetamidoethylene from mixtures additionally containing acetamide, especially preparation products.Type: GrantFiled: November 24, 1981Date of Patent: August 30, 1983Assignee: Dynapol Shareholders Liquidating TrustInventor: David P. Matzinger
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Patent number: 4324911Abstract: A process for the continuous preparation of diacetyl ethylene diamine, w hich comprises allowing a mixture of ethylene diamine and acetic acid to react in a low-temperature zone at a temperature of about 80.degree. to 140.degree. C., completing the reaction of the mixture in a subsequent high-temperature zone of from about 140.degree. to 215.degree. C., discharging the diacetyl ethylene diamine obtained at the end of the high-temperature zone and stripping the reaction water in countercurrent flow by an inert gas at a point located between the low-temperature and the high-temperature zone.Type: GrantFiled: October 7, 1980Date of Patent: April 13, 1982Assignee: Hoechst AktiengesellschaftInventor: Werner Wellbrock
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Patent number: 4316846Abstract: The present invention relates to the recovery of three aprotic amide solvents from their water solutions by extraction with a selected class of organic solvents characterized generally by having two electron withdrawing substituents, exemplified by fluorine and chlorine, located on a carbon atom which also contains a hydrogen atom.Type: GrantFiled: May 22, 1978Date of Patent: February 23, 1982Assignee: Custom Organics, Inc.Inventors: Gilbert Gavlin, Romas Cesas
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Patent number: 4306068Abstract: A method for separating primary and secondary amines by contacting a mixture thereof with mesityl oxide, which forms acetone and an adduct with the primary amine. Acetone is removed to force the reaction. The reaction is particulary useful for separating close boiling amines. The primary amine adducts have high boiling points, thereby allowing the secondary amine to be recovered in high purity by distillation. The primary amine may also be recovered by hydrolyzing the adduct which produces the primary amine and acetone.Type: GrantFiled: March 23, 1978Date of Patent: December 15, 1981Assignee: Chemical Research and Licensing CompanyInventor: Lawrence A. Smith, Jr.
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Patent number: 4251460Abstract: A process for producing dimethylformamide which comprises reacting methanol and ammonia to give methylamines, separating a dimethylamine-trimethylamine mixture from the methylamines, and reacting the dimethylamine-trimethylamine mixture with carbon monoxide to produce dimethylformamide.Type: GrantFiled: December 19, 1979Date of Patent: February 17, 1981Assignee: Nitto Chemical Industry Co., Ltd.Inventors: Takeyuki Fujita, Masaru Suto, Kazumoto Ogura