Air, Oxygen, Or Ozone Oxidant Patents (Class 562/412)
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Patent number: 6984753Abstract: A process for producing aromatic dicarboxylic acids by the oxidation of dimethylbenzenes wherein dimethylbenzenes are mixed with an oxygen containing gas, solvent and catalyst in a reactor and the reaction mixture is agitated with one or more asymmetric radial impellers in combination with at least one axial impeller.Type: GrantFiled: April 24, 2002Date of Patent: January 10, 2006Assignee: Dow Italia s.r.l.Inventors: Andreas Gnagnetti, Luciano Piras, Kishore K. Kar
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Patent number: 6949673Abstract: Improved process for producing aromatic carboxylic acids by catalytic liquid phase oxidation of a corresponding precursor in a suitable solvent comprising feeding the reactants to a first oxidation reaction zone at high pressure and high solvent ratio, wherein uptake of oxygen is less than that required for full conversion of the precursor to its corresponding carboxylic acid, and then feeding the resulting reaction medium to a second oxidation reaction zone.Type: GrantFiled: March 21, 2003Date of Patent: September 27, 2005Assignee: E.I. Du Pont de Nemours and CompanyInventors: Samuel Duncan Housley, John A Turner
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Patent number: 6852879Abstract: Disclosed is a method and solvent composition capable of removing iron oxide deposits from the surface of titanium components without substantially damaging the underlying titanium component. Iron oxide deposits may be removed from the surface of a titanium component by contacting the titanium component with the solvent composition of the invention. The solvent composition may then be removed from contact with the titanium component to obtain a recyclable solvent composition which is recycled into repeated contact with the titanium component. The solvent composition comprises an aqueous mixture of an organic acid and a hydrohalide acid.Type: GrantFiled: September 26, 2002Date of Patent: February 8, 2005Assignee: BP Corporation North America Inc.Inventors: Frank G. Belmonte, Kenneth J. Abrams, James Delaney, Jr., Scott G. Kramer, David L. Sikkenga
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Publication number: 20040254397Abstract: A method and apparatus for the conversion of aromatic alkyls to aromatic carboxylic acids in a reactor are provided, wherein the location of the feeding of the reaction mixture into the reactor significantly increases the conversion efficiency of the precursor materials.Type: ApplicationFiled: June 13, 2003Publication date: December 16, 2004Applicant: TEREFTALATOS MEXICANOS, S.A. de C.V.Inventors: Fernando Varela-Fuentes, Arturo Bulbarela-Croda, Guillermo Ramirez-Aguilar, Bertha Moran-Delgado
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Publication number: 20040242922Abstract: The present invention relates to a process for the oxidation of hydrocarbons, in particular of branched or unbranched saturated aliphatic hydrocarbons, of cycloaliphatic or alkylaromatic hydrocarbons or of alcohols and/or ketones, to acid or polyacid compounds.Type: ApplicationFiled: July 8, 2004Publication date: December 2, 2004Inventors: Didier Bonnet, Eric Fache, Jean-Pierre Simonato
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Publication number: 20040230066Abstract: Citalopram can be industrially and economically produced and at a high yield by reacting a compound of the following formula [VI] with 3-(dimethylamino)propyl chloride in the presence of at least one of N,N,N′,N′-tetramethylethylenediamine and 1,3-dimethyl-2-imidazolidinone and a condensing agent. The compound of the following formula [III], which is a key compound for the production of citalopram, can be easily produced by subjecting the compound of the following formula [II] to reduction and cyclization.Type: ApplicationFiled: June 14, 2004Publication date: November 18, 2004Applicant: Sumika Fine Chemicals Co., Ltd.Inventors: Tetsuya Ikemoto, Wei-Guo Gao, Masami Igi
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Publication number: 20040225148Abstract: A process for producing aromatic dicarboxylic acids which comprises subjecting an aromatic compound having an alkyl substituent or a partially oxidized alkyl substituent to liquid-phase oxidation with a molecular oxygen-containing gas in a reaction solvent in the presence of a catalyst, then conducting solid-liquid separation of the formed slurry containing crystals of the produced aromatic dicarboxylic acid, and recovering the crystals, wherein when carrying out solid-liquid separation of the slurry by continuously supplying it to a screen-type centrifugal separator having a screw conveyor disposed therein, a screen with an opening size that allows partial escape of crystals in the supplied slurry through the screen openings is used as the screen of the screen-type centrifugal separator. According to this method, clogging of the centrifugal separator is prevented and solid-liquid separation can be carried out efficiently.Type: ApplicationFiled: February 25, 2004Publication date: November 11, 2004Applicant: Mitsubishi Chemical CorporationInventors: Takayuki Isogai, Motoki Numata
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Publication number: 20040199006Abstract: A process for the production of an aromatic carboxylic acid comprising contacting in the presence of a catalyst, within a continuous flow reactor, one or more precursors of the aromatic carboxylic acid with an oxidant, such contact being effected with said precursor(s) and the oxidant in an aqueous solvent comprising water under supercritical conditions or near supercritical conditions close to the supercritical point such that said one or more precursors, oxidant and aqueous solvent constitute a substantially single homogeneous phase in the reaction zone, wherein the contact of at least part of said precursor with said oxidant is contemporaneous with contact of said catalyst with at least part of said oxidant.Type: ApplicationFiled: April 28, 2004Publication date: October 7, 2004Applicant: E. I. duPont de Nemours and CompanyInventors: Derek Alexander Graham, Paul Anthony Hamley, Raymond Oliver, Martyn Poliakoff, Duncan C. Woodcock, Thomas Ilkenhans
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Publication number: 20040171871Abstract: An aromatic compound (C) is reacted with carbon monoxide (D) and molecular oxygen (E) in the presence of a palladium compound catalyst (A) and a catalyst (B) and thereby yields a aromatic carboxylic acid corresponding to the aromatic compound (C) except with one or more carboxyl groups bonded to its aromatic ring. The catalyst (B) contains a heteropolyacid or a salt thereof (B1) or a mixture of oxo acids and/or salts thereof (B2), and the mixture (B2) contains, as a whole, one of P and Si and at least one selected from V, Mo and W.Type: ApplicationFiled: February 26, 2004Publication date: September 2, 2004Inventors: Yasutaka Ishii, Tatsuya Nakano
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Publication number: 20040147777Abstract: The present invention relates to a process for the oxidation of hydrocarbons, in particular of branched or unbranched saturated aliphatic hydrocarbons or of cycloaliphatic or alkylaromatic hydrocarbons, to alcohol, ketone and/or acid or polyacid compounds.Type: ApplicationFiled: March 22, 2004Publication date: July 29, 2004Inventors: Eric Fache, Jean-Pierre Simonato
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Patent number: 6768013Abstract: A novel process for the direct oxidation of hydrogen and hydrocarbons is disclosed, where the explosion risks inherent in gas phase oxidations are substantially eliminated. Gaseous oxidation reactants are soluble in a first reaction solvent phase such as a perfluorocarbon (e.g. C8F18) and the oxidation product is preferentially soluble in a second product solvent phase such as water or a dilute acid. A solid catalyst such as palladium on alumina is then contacted with the dissolved reactants. The oxidation product such as hydrogen peroxide may be separated from the reaction solvent phase by extraction into the immiscible product solvent phase and then separated from it by distillation, thereby allowing re-use of the aqueous phase. The present invention may be carried out using a two-phase reaction system whereby both the reaction solvent and product solvent are contained within a reaction vessel into which the solid catalyst is slurried and mechanically agitated to promote the reaction.Type: GrantFiled: June 15, 2001Date of Patent: July 27, 2004Assignee: UOP LLCInventor: Peter R. Pujado
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Publication number: 20040143135Abstract: In a method of producing pyromellitic acid by liquid-phase oxidizing 2,4,5-trimethylbenzaldehyde in a water solvent with molecular oxygen, a recrystallization mother liquor separated in a recrystallization step is recycled to the oxidation step after a part of the water solvent is removed. With this method, the loss of pyromellitic acid and the oxidation catalyst can be minimized and the burden of discharging the waste water is reduced without lowering the efficiency of the liquid-phase oxidation reaction.Type: ApplicationFiled: January 13, 2004Publication date: July 22, 2004Inventors: Tatsuyuki Kumano, Seiji Adachi, Hiroshi Ogawa
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Patent number: 6765113Abstract: A process for the production of an aromatic carboxylic acid comprising contacting in the presence of a catalyst, within a continuous flow reactor, one or more precursors of the aromatic carboxylic acid with an oxidant, such contact being effected with said precursor(s) and the oxidant in an aqueous solvent comprising water under supercritical conditions or near supercritical conditions close to the supercritical point such that said one or more precursors, oxidant and aqueous solvent constitute a substantially single homogeneous phase in the reaction zone, wherein the contact of at least part of said precursor with said oxidant is contemporaneous with contact of said catalyst with at least part of said oxidant.Type: GrantFiled: July 13, 2001Date of Patent: July 20, 2004Assignee: E.I. Du Pont de Nemours and CompanyInventors: Derek Alexander Graham, Paul Anthony Hamley, Raymond Oliver, Martyn Poliakoff, Duncan Woodcock, Thomas Ilkenhans
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Patent number: 6761860Abstract: A description is given here of a novel process for the production of monocarboxylic and polycarboxylic aromatic acids by the catalytic oxidation in homogeneous phase of aromatic compounds carrying at least one oxidizable substituent group attached directly to the carbon atom of the corresponding aromatic nucleus. The novel process according to the present invention comprises the steps of: a) catalytically oxidizing the corresponding aromatic precursors in liquid phase in the presence of gaseous oxygen; b) filtering the end product; c) recycling into the oxidation reactor at least part of the mother liquors resulting from the filtration stage, and is characterized by the fact that said steps from (a) to (c) are carried out in a closed and continuous cycle operating substantially under the same pressure and temperature conditions, preferably at 2-10 barg and 100-140° C.Type: GrantFiled: June 3, 2002Date of Patent: July 13, 2004Inventors: Franco Codignola, Antonio Moro
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Patent number: 6759550Abstract: The present invention pertains to an improved method of oxidizing substituted aromatic compounds (such as p xylene) to their corresponding aromatic acids (such as terephthalic acid). The improvement involves carrying out the oxidation reaction in an aqueous medium, wherein the aqueous medium contains at least 30 percent water, preferably up to 30 percent surfactant and preferably a low molecular weight material containing a hydrophilic end group as a co-surfactant. The reaction is carried out at a pH of less than 3.0.Type: GrantFiled: November 13, 2002Date of Patent: July 6, 2004Assignee: The Dow Chemical CompanyInventors: John Klier, Christopher J. Tucker, Thomas H. Kalantar, Kenneth A. Burdett, Daniel Patrick Green, Luciano Piras, Sergio Schena, Guo-shuh John Lee
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Patent number: 6753290Abstract: The present invention relates to catalyst compositions for purifying terephthalic acid from p-carboxybenzaldehyde, based on Group VIII metals, comprising crystallites of catalytically active palladium or of palladium and at least one metal of Group VIII of the Periodic Table of Elements, applied to the surface of a carbon material, wherein a mesoporous graphite-like material with the average mesopore size in the range of from 40 to 400 Å, the proportion of the mesopores in the total pore volume of at least 0.5, and the degree of graphite-similarity of at least 20% is used as the carbon material, in which metal crystallites are distributed in the volume of the carbon material granules in such a manner that the distribution peaks of these crystallites should be at a distance from the outer surface of the granule corresponding to 1-30% of its radius.Type: GrantFiled: May 6, 2002Date of Patent: June 22, 2004Assignees: Institut Kataliza Imeni G.K. Boreskova Sibirskogo Otdelenia Rossiiskoi Akademii Nauk, Samsung General Chemicals Co., Ltd.Inventors: Anatoly Vladimirovich Romanenko, Vladimir Alexandrovich Likholobov, Maria Nikolaevna Timofeeva, Jhung Sung Hva, Park Jun Seok
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Publication number: 20040087814Abstract: The present invention relates to a process for producing aromatic dicarboxylic acids by the oxidation of dimethylbenzenes wherein the dimethylbenzenes are mixed with an oxygen containing gas, solvent and catalyst in a reactor, the improvement comprising agitating the reaction mixture with one or more asymmetric radial impellers in combination with at least one axial impeller.Type: ApplicationFiled: September 2, 2003Publication date: May 6, 2004Inventors: Andreas Gnagnetti, Luciano Piras, Kishore K. Kar
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Patent number: 6670502Abstract: Process for producing mono- and poly-carboxylic aromatic acids wherein an aromatic compound having at least one oxidizable substituent directly linked to the carbon atom of the corresponding aromatic nucleus is oxidized in the presence of a catalyst system in the liquid homogenous phase. The oxidation reaction is carried out in aqueous acetic acid, and the catalyst system consists of a combination of cobalt and zirconium organic salts. The oxidation reaction is carried out at an absolute pressure lower than 10 bar and at a temperature of 90-150° C.Type: GrantFiled: September 28, 2000Date of Patent: December 30, 2003Inventor: Franco Codignola
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Publication number: 20030216577Abstract: A process for catalytically oxidizing alkylaromatic compounds of the formula (I)Type: ApplicationFiled: May 15, 2003Publication date: November 20, 2003Inventors: Walther Jary, Peter Poechlauer, Thorsten Ganglberger
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Patent number: 6649791Abstract: The present invention relates to the preparation of an aromatic carboxylic acid by contacting an alkyl aromatic compound with an oxygen containing gas in the presence of a encapsulated oxo-bridged organometallic cluster catalyst.Type: GrantFiled: June 28, 2001Date of Patent: November 18, 2003Assignee: Council of Scientific and Industrial ResearchInventors: Darbha Srinivas, Suhas Arunkumar Chavan, Paul Ratnasamy
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Publication number: 20030208091Abstract: A process for producing pyromellitic acid which comprises oxidizing 2,4,5-trimethylbenzealdehyde and/or its oxidized derivative in the presence of a catalyst containing iron, manganese and bromine, or additionally containing zirconium or cerium continuously or semi-continuously using aqueous acetic acid solvent and 0.05-2% by weight of bromide ion. The catalyst used in the present invention has high activity, and the catalyst solution has low corrosive because the reaction is performed at low bromide concentration by using a solvent of aqueous acetic acid. So pyromellitic acid is produced industrially advantageously in high yield continuously or semi-continuously which has been a major difficulty up to now.Type: ApplicationFiled: May 19, 2003Publication date: November 6, 2003Inventors: Kazuo Tanaka, Hiroshi Ogawa, Ikutraro Maruki, Atsushi Okoshi
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Publication number: 20030181755Abstract: A novel process for the purification of crude aromatic carboxylic acids, such as, for example, terephthalic acid, orthophthalic acid, trimesic acid, isophthalic acid, 2,6-naptlithalenedicarboxylic acid and pyromellitic acid, which are obtained by oxidising the corresponding aromatic precursors is described; the process is based on the subsequent oxidation in heterogeneous phase of the crude product in aqueous solution.Type: ApplicationFiled: January 9, 2003Publication date: September 25, 2003Inventor: Franco Codignola
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Patent number: 6620966Abstract: There is disclosed a process for continuously producing an aromatic carboxylic acid comprising the steps of (A) subjecting a poly-alkyl aromatic hydrocarbon to a liquid-phase oxidation by continuously supplying an oxidation reactor with said hydrocarbon, a catalyst, a reaction accelerator, acetic acid containing water and a gas containing molecular oxygen; (B) continuously taking out from the oxidation reactor, the reaction products containing aromatic carboxylic acids, and separating the same into crude aromatic carboxylic acids and acetic acid containing water; and (C) continuously taking out from the oxidation reactor, the oxidative reaction exhaust gas containing evaporated acetic acid containing water, introducing the above gas in a condenser, and condensing the above evaporated acid, wherein acetic acid containing water is supplied to an oxidative reaction exhaust gas inlet line leading to the condenser.Type: GrantFiled: January 16, 2002Date of Patent: September 16, 2003Assignees: Mitsubishi Gas Chemical Company, Inc., Toyo Boseki Kabushiki Kaisha, Mizushima Aroma Company, Ltd.Inventors: Fumio Ohkoshi, Ikuo Tsuboi, Nirou Hoshishima
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Publication number: 20030166967Abstract: The present invention relates to a process for oxidizing hydrocarbons, in particular branched or unbranched saturated aliphatic hydrocarbons, cycloaliphatic or alkylaromatic hydrocarbons to acidic or polyacidic compounds.Type: ApplicationFiled: December 2, 2002Publication date: September 4, 2003Inventor: Eric Fache
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Patent number: 6528683Abstract: The invention relates to a method for producing shell catalysts for the catalytic vapor-phase oxidation of aromatic carboxylic acids and/or carboxylic acid anhydrides comprised of a supporting core and of catalytically active metal oxides which are deposited in a shell-shaped manner on said supporting core. The inventive catalysts are obtained by spraying an aqueous active mass suspension, said suspension containing the active metal oxides, at higher temperatures onto the hot supporting material which has a temperature ranging from 50 to 450° C. The aqueous active mass suspension contains 1 to 10 wt. %, with regard to the solid content of the active mass suspension, a binding agent comprised of A) a polymerizate obtained by radical polymerization, containing 5 to 100 wt. % of monomers (a) in the form of ethylenically unsaturated acid anhydrides or ethylenically unsaturated dicarboxylic acids whose carboxyl groups can form an anhydride and containing 0 to 95 wt.Type: GrantFiled: November 30, 2000Date of Patent: March 4, 2003Assignee: BASF AktiengesellschaftInventors: Thomas Heidemann, Frank Rosowski, Gerd Linden, Michael Seufert, Gerhard Hefele, Peter Michael Lorz
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Patent number: 6521786Abstract: A description is given here of a novel process for the production of monocarboxylic and polycarboxylic aromatic acids by the catalytic oxidation in homogeneous phase of aromatic compounds carrying at least one oxidizable substituent group attached directly to the carbon atom of the corresponding aromatic nucleus. The novel process according to the present invention comprises the steps of: a) catalytically oxidizing the corresponding aromatic precursors in liquid phase in the presence of gaseous oxygen; b) filtering the end product; c) recycling into the oxidation reactor at least part of the mother liquors resulting from the filtration stage, and is characterized by the fact that said steps from (a) to (c) are carried out in a closed and continuous cycle operating substantially under the same pressure and temperature conditions, preferably at 2-10 barg and 100-140° C.Type: GrantFiled: August 8, 2001Date of Patent: February 18, 2003Inventors: Franco Codignola, Antonio Moro
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Patent number: 6506931Abstract: A process for producing an aromatic carboxylic acid by a liquid phase oxidation of an alkylaromatic compound with molecular oxygen in a reaction solvent comprising a lower aliphatic carboxylic acid in the presence of an oxidation catalyst, in which an aromatic carboxylic acid having an improved hue of the powdery product thereof and exhibiting an improved light transmittance when dissolved in an aqueous solution of a base can be produced efficiently in a simple manner by suppressing contamination due to the intermediates and by-products formed by side reactions, the said process comprising performing the liquid phase oxidation of the alkylaromatic compound in the presence of a hydrogen gas-treated liquid containing the catalyst.Type: GrantFiled: September 7, 2000Date of Patent: January 14, 2003Assignee: Mitsui Chemicals, Inc.Inventors: Masayasu Ishibashi, Hiroshi Tomita
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Patent number: 6506932Abstract: A method for oxidizing an aromatic compound possesssing at least one alkyl substituent by using a catalyst avoids containing a corrosive bromine ion, remains stably without being decomposed even in an oxidizing atmospherfe, and permits reclamation is provided. An aromatic compound possessing at least one alkyl substituent is oxidized by using a catalyst which has at least one kind of element selected from the group consisting of phosphorus, silicon, and germanium as a hetero atom and at least one kind of element selected from the group consisting of molybdenum, tungsten, vanadium, and niobium as a poly atom and comprises a heteropoly-oxometalate anion possessing two defective structure site and at least one kind of element selected from the group of elements of Periods 4˜6 of Groups IB, VA,VIIA, and VIII in the Periodic Table of the Elements.Type: GrantFiled: November 7, 2001Date of Patent: January 14, 2003Assignee: Nippon Shokubai Co., Ltd.Inventors: Yasutaka Sumida, Masahiro Wada, Noritaka Mizuno
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Patent number: 6504051Abstract: Disclosed is an improved process for the continuous production of aromatic carboxylic acids by the liquid-phase oxidation of an alkyl aromatic compound with an oxygen-containing gas in the presence of oxidation catalyst which results in reduced wastewater generation, reduced condensing capacity requirements, and, optionally, increased power recovery, and. The process effectively utilizes the heat of reaction in the process of removing excess water generated from the reaction and minimizes the loss of solvent used as the carrier for the reaction catalyst by removing reactor off-gas directly into a water removal column for distillation. A portion of the overhead aqueous vapors are removed from the top of the water removal column as a vapor distillate, with the remaining overhead aqueous vapors being condensed then subsequently refluxed to the fractionating zone of the water removal column.Type: GrantFiled: June 4, 2001Date of Patent: January 7, 2003Assignee: Eastman Chemical CompanyInventors: Harold David Miller, Jr., Robert Lin, Marcel de Vreede
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Patent number: 6500347Abstract: A process for recovering crystals from a slurry which comprises supplying a slurry comprising crystals and a solvent to a rotary vacuum filter and successively conducting filtration under suction, washing, filtration under suction and cleavage of a cake continuously by rotation of a cylindrical filter medium, wherein a vapor having a same composition as that of the solvent is supplied as a blowing gas for cleaving the cake. The crystals can be continuously recovered for a long period of time without clogging of a filter medium when the crystals are recovered from a slurry by using a rotary vacuum filter.Type: GrantFiled: July 3, 2001Date of Patent: December 31, 2002Assignees: Mitsubishi GAs Chemical Company, Inc., Toyo Boseki Kabushiki Kaisha, Mizushima Aroma Company, Ltd.Inventors: Fumio Ohkoshi, Masato Inari
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Publication number: 20020193629Abstract: Disclosed is an improved process for the continuous production of aromatic carboxylic acids by the liquid-phase oxidation of an alkyl aromatic compound with an oxygen-containing gas in the presence of oxidation catalyst which results in reduced wastewater generation, reduced condensing capacity requirements, and, optionally, increased power recovery, and. The process effectively utilizes the heat of reaction in the process of removing excess water generated from the reaction and minimizes the loss of solvent used as the carrier for the reaction catalyst by removing reactor off-gas directly into a water removal column for distillation. A portion of the overhead aqueous vapors are removed from the top of the water removal column as a vapor distillate, with the remaining overhead aqueous vapors being condensed then subsequently refluxed to the fractionating zone of the water removal column.Type: ApplicationFiled: June 4, 2001Publication date: December 19, 2002Inventors: Harold David Miller, Robert Lin, Marcel de Vreede
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Patent number: 6476257Abstract: The present invention relates to a method for preparing aromatic carboxylic acid from alkylaromatics by liquid-phase oxidation. More particularly, the present invention relates to a method for preparing aromatic carboxylic acid from alkylaromatics by oxidation in acetic acid as solvent with oxygen-containing gas in the presence of cobalt/manganese/bromine complex catalyst, wherein nickel and carbon dioxide in an appropriate amount are added to increase an activity of cobalt/manganese/bromine complex catalyst. Especially nickel has a synergistic effect with carbon dioxide and maximize the to formation of the desired product having the corresponding carboxylic groups to the number of alkyl groups in a reactant.Type: GrantFiled: September 28, 2001Date of Patent: November 5, 2002Assignee: Korea Institute of Chemical TechnologyInventors: Sang-Eon Park, Jin S. Yoo, Ki-Won Jun, David B. Raju, Young-Ho Kim
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Patent number: 6469205Abstract: Xylene derivatives, such as chloro-ortho-xylene, are oxidized in the absence of solvent or added promoter in the presence of at least one metal catalyst. The primary products are chlorophthalic anhydride and chlorotoluic acid.Type: GrantFiled: November 14, 2000Date of Patent: October 22, 2002Assignee: General Electric CompanyInventor: Tohru Takekoshi
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Patent number: 6465685Abstract: Xylene derivatives, such as chloro-ortho-xylene, are oxidized in a solvent in the presence of at least one metal catalyst with addition of promoter after the reaction has proceeded to an intermediate stage of conversion to product mixture. The product comprises chlorophthalic acid or chlorophthalic anhydride.Type: GrantFiled: November 20, 2000Date of Patent: October 15, 2002Assignee: General Electric CompanyInventors: Peter David Phelps, Donald Frank Rohr, Jr., Sheree Lynell Schattenmann
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Patent number: 6448436Abstract: Disclosed is an integrated process for producing 2,6-naphthalene dicarboxylicacid comprising oxidizing a methylnaphthalene feedstock, hydrodebrominating the crude naphthoic acid product under conditions different from any work known in the art, forming a potassium salt of the acid; disproportionating the potassium salt to produce 2,6 potassium salts of NDA; selectively precipitating K2NDA; selectively precipitating the monopotassium salt of 2,6 NDA(KHNDA); disproportionating the KHNDA into 2,6 NDA and K2NDA; further reacting the 2,6 NDA in a pipe reactor; and drying the product 2,6 NDA by conventional means or directly slurrying directly into a PEN process. The process can tolerate impurities in the economical methylnaphthalene feed and the resulting 2,6 NDA is of high quality with <50 ppm potassium.Type: GrantFiled: August 22, 2000Date of Patent: September 10, 2002Assignee: Mossi & Ghisolfi Overseas, S. A.Inventors: Keith Michael Kreitman, Steve Edward Brewer, John Bernard Rodden, Robert Lawrence Blackbourn, Thomas Fairchild Brownscombe, James Laurel Buechele, Ye-Mon Chen, Zaida Diaz, Donn Anthony DuBois, Raymond Lawrence June, Brendan Dermot Murray, Michael Wayne Potter
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Patent number: 6440327Abstract: Compositions and methods for inhibiting scale are provided. Pursuant to the present invention, a composition for inhibiting scale is provided that includes a carbohydrate polymer having both nitrogen-containing groups and carboxyl groups. The nitrogen-containing groups include amino groups, amido groups and mixtures thereof. The present invention has been found useful for inhibiting scale in industrial waters, such as, pulp bleach plant process waters which contain calcium oxalate and barium sulfate scale.Type: GrantFiled: January 31, 2001Date of Patent: August 27, 2002Assignee: Ondeo Nalco CompanyInventors: Sergey M. Shevchenko, Prasad Y. Duggirala
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Publication number: 20020091285Abstract: The present invention relates to a method for increasing the production capacity of a conventional oxidation reactor for catalytic liquid phase oxidation of paraxylene by staging the oxidation reaction into a first high pressure and high solvent ratio reaction zone followed by the conventional reactor.Type: ApplicationFiled: June 19, 2001Publication date: July 11, 2002Inventors: Samuel Duncan Housley, John A. Turner
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Patent number: 6355835Abstract: The present invention relates to a process for the preparation of benzene dicarboxylic acids by liquid phase oxidation of Xylene isomers using oxygen or air by oxidising in the presence of acetic acid as solvent, cobalt salt as catalyst and an initiator. The oxidation step is followed by flashing the said reaction mixture to remove volatile substances and cooling and filtering to get crude benzene di-carboxylic acid as a solid product and filtrate. The dicarboxylic acid solid product is recrystallised to get at least 99% pure benzene. The filtrate may be recycled.Type: GrantFiled: December 8, 1999Date of Patent: March 12, 2002Assignee: Chemintel (India) Private LimitedInventors: Girendra Narain Kulsrestha, Mahendra Pratap Saxena, Ashok Kumar Gupta, Satish Kumar Sharma, Dinesh Prasad Bangwal, Hari Bhagwan Goyal, Rameshwar Prasad, Sanjib Mall, Prakash D. Patel
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Patent number: 6355834Abstract: Disclosed is a process for manufacturing an aromatic diacid in one step with a single catalyst system which comprises: a) Introducing into a reactor an aromatic hydrocarbon containing the number of rings desired in the product diacid with one or more alkyl groups attached to the rings; b) Reacting said aromatic hydrocarbon in the presence of an oxidant supply and a single catalyst system comprising at least one catalyst selected from Group IB, IIB, VB, or VIIB of the Periodic Table, in a reaction medium capable of stabilizing the aromatic acids formed against further oxidation to water and CO2, or decarboxylation to aromatic hydrocarbons, and also capable of allowing the isomerization of the acids so formed to the desired diacids; and c) Reacting said hydrocarbon feed with said oxidant in the presence of said catalyst system until a desired amount of said feed is oxidized to carboxylic acids and isomerized to the desired diacid product.Type: GrantFiled: August 22, 2000Date of Patent: March 12, 2002Assignee: Shell Oil CompanyInventors: Thomas Fairchild Brownscombe, Susan Secor Pfrehm, William Larry King
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Publication number: 20010034459Abstract: The invention relates to a process for preparing a compound of the formula (I) 1Type: ApplicationFiled: December 21, 2000Publication date: October 25, 2001Inventors: Andreas Meudt, Stefan Scherer, Antje Norenberg, Peter Koch, Steffen Haber
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Patent number: 6307099Abstract: An aromatic carboxylic acid such as terephthalic acid is produced by the liquid phase oxidation of a precursor thereof, the oxidation being carried out in such a way that substantially all of the aromatic carboxylic acid produced in the course of the reaction is maintained in solution during the reaction.Type: GrantFiled: January 7, 2000Date of Patent: October 23, 2001Assignee: E. I. du Pont de Nemours and CompanyInventors: John Arthur Turner, David John Royall, Duncan Stuart Hugall, Graham Howard Jones, Duncan Charles Woodcock
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Patent number: 6288273Abstract: The invention relates to a method for producing gas-phase catalysts gas-phase oxidation of aromatic hydrocarbons into carboxylic acids and/or carboxylic acid anhydrides upon whose carrier material a coating containing catalytically active metal oxide is applied in the form of a shell, wherein a powder is initially produced from a solution and/or suspension of catalytically active metal oxides and the precursor compounds thereof or simply the precursor compounds in the presence or absence of auxiliary agents in order to produce the catalyst. Said powder is then applied, in the form of a shell, to the carrier in the presence or absence of auxiliary agents after or without previous conditioning and without previous thermal treatment to produce the catalyst. The carrier which is thus coated undergoes thermal treatment in order to produce catalytically active metal oxides.Type: GrantFiled: August 26, 1999Date of Patent: September 11, 2001Assignee: BASF AktiengesellschaftInventors: Thomas Heidemann, Thomas Cimniak, Bernhard Ulrich
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Publication number: 20010018543Abstract: An aromatic carboxylic acid, aromatic aldehyde, and aromatic alcohol are simultaneously and efficiently prepared by liquid phase oxidizing an aromatic compound represented by formula (I) with a gas containing molecular oxygen, in a presence of a catalyst comprising transition metal compound, tertiary amine and bromide compound: 1Type: ApplicationFiled: March 19, 2001Publication date: August 30, 2001Applicant: Toray Industries, Inc.Inventors: Shotaro Matsuoka, Masaaki Suematsu, Akira Kitamura
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Patent number: 6281382Abstract: The method of oxidizing the alkyl groups of alkylbenzenes using palladium phenanthroline acetate or a palladium acetate with modified phenanthroline ligand catalyst. The palladium acetate catalyst with modified phenanthroline has the following formula: wherein R1 is selected from the group consisting of alkyl groups of from 1 to 3 carbon atoms, OH, and NO2 groups and halogen and hydrogen atoms with at least six of the R1 groups being hydrogen atoms in the ligand.Type: GrantFiled: June 1, 2000Date of Patent: August 28, 2001Assignee: Georgia Tech Research Corp.Inventors: Mark G. White, Alexei V. Iretski
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Publication number: 20010016667Abstract: An aromatic carboxylic acid, aromatic aldehyde, and aromatic alcohol are simultaneously and efficiently prepared by liquid phase oxidizing an aromatic compound represented by formula (I) with a gas containing molecular oxygen, in a presence of a catalyst comprising transition metal compound, tertiary amine and bromide compound: 1Type: ApplicationFiled: March 19, 2001Publication date: August 23, 2001Applicant: Toray Industries, Inc.Inventors: Shotaro Matsuoka, Masaaki Suematsu, Akira Kitamura
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Patent number: 6268528Abstract: Dialkylnaphthalene is oxidized to naphthalenedicarboxylic acid in a lower aliphatic carboxylic acid solvent in the presence of a catalyst comprising a cobalt compound, a manganese compound and a bromine compound having an atomic ratio of manganese to cobalt of 0.03 to 0.5. The catalyst is supplied to the oxidation reaction zone so that the total amount of cobalt and manganese is 0.025 to 0.1 gram atom based on 1 gram mol of the dialkylnaphthalene. An oxidation product slurry is subjected to solid-liquid separation when the concentration of the naphthalenedicarboxylic acid in the slurry is 8 to 30% by weight. The process prevents the by-production of benzotricarboxylic acid such as trimellitic acid, thereby drastically reducing the incorporation of heavy metal complexes with trimellitic acid into naphthalenedicarboxylic acid crystals.Type: GrantFiled: November 3, 1999Date of Patent: July 31, 2001Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Hiroshi Machida, Fumiya Zaima, Masato Inari, Hiroshi Watanabe, Emiko Yokose
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Patent number: 6255525Abstract: A process for preparing an aromatic carboxylic acid having improved purity comprising contacting at an elevated temperature and pressure a mixture comprising an impure aromatic carboxylic acid and a solvent in the presence of hydrogen gas with a carbon catalyst which is essentially free of a hydrogenation metal component.Type: GrantFiled: December 1, 1998Date of Patent: July 3, 2001Assignee: BP Amoco CorporationInventors: David Lee Sikkenga, M. Michelle Morie-Bebel, Stephen V. Hoover
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Patent number: 6194607Abstract: An improved production method of aromatic carboxylic acid products of significantly improved yield and quality by oxidizing alkyl aromatic substrates or their partially oxidized intermediates in a conventional MC-type catalyst system modified to contain additional components such as alkali metal or alkaline earth metal in an acetic acid medium in a feed gas containing oxygen and optionally carbon dioxide. Since carbon dioxide functioned as a co-oxidant along with oxygen in the oxidation reaction, the oxidation reaction proceeds more selectively to produce the carboxylic acid product much faster under milder reaction conditions over the conventional MC-type oxidation. In particular, the oxidation of para-xylene carried out by the novel present method enabled production of terephthalic acid of higher yield and enhanced quality, which were improved far more than the extent that generally could be expected by current PTA producers.Type: GrantFiled: December 3, 1999Date of Patent: February 27, 2001Assignee: Samsung General Chemicals Co., Ltd.Inventors: Sung-Hwa Jhung, Youn-Seok Park, Ki-Hwa Lee, Jin Sun Yoo, Jong-Hyun Chae
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Patent number: 6180822Abstract: An improved production method of aromatic carboxylic acid products of significantly improved yield and quality, the method including oxidizing alkyl aromatic substrates or their partially oxidized intermediates in a catalyst system containing a conventional catalyst and, if deemed necessary, additional components such as a transition metal or lanthanide series metal, in an acetic acid medium, with a feed gas containing both oxygen and carbon dioxide. Since carbon dioxide functions as a co-oxidant along with oxygen in the oxidation reaction, the oxidation reaction proceeds more selectively to produce the carboxylic acid product much faster under milder reaction conditions as compared to the conventional oxidation.Type: GrantFiled: December 3, 1999Date of Patent: January 30, 2001Assignee: Samsung General Chemical Co., Ltd.Inventors: Sung-Hwa Jhung, Ki-Hwa Lee, Youn-Seok Park, Jin Sun Yoo
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Patent number: 6175038Abstract: An improved production method of aromatic carboxylic acids of significantly improved yields and quality by oxidizing alkyl aromatic substrates or their partially oxidized intermediates by oxygen-enriched gas in a conventional Co—Mn—Br catalyst system containing additional components such as a transition metal or lanthanide metal component in an aliphatic carboxylic acid having 1˜6 carbon atoms. In other words, a decline in reactivity in the later part of the oxidation reaction and the precipitation of a catalyst such as manganese were effectively deterred by means of incorporating one or more than one type of transition or lanthanide metal components selected from such metals as Ce, Zr, Hf, Fe, Cr, and Mo during the oxidation reaction with oxygen-enriched gas. With this invention, pure aromatic carboxylic acids with white color can be obtained with high selectivity and reactivity by oxidation of substrates with oxygen-enriched gas.Type: GrantFiled: December 3, 1999Date of Patent: January 16, 2001Assignee: Samsung General Chemicals Co., Ltd.Inventors: Sung-Hwa Jhung, Youn-Seok Park