Producing Unsaturated Acid Patents (Class 562/545)
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Publication number: 20040249201Abstract: A method for producing acrylic acid from an acrylic acid-containing solution of high concentration without performing azeotropic distillation is provided. This method of producing acrylic acid comprises steps of absorbing acrylic acid-containing gas, distilling the acrylic acid-containing solution without using an azeotropic solvent thereby obtaining crude acrylic acid as a column bottom stream and/or a column side stream, and supplying the crude acrylic acid to a crystallizing step and melt crystallizing the crude acrylic acid thereby obtaining purified acrylic acid.Type: ApplicationFiled: June 2, 2004Publication date: December 9, 2004Inventors: Kouji Ueno, Harunori Hirao, Naoki Serata, Takeshi Yokogoshiya
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Publication number: 20040242925Abstract: A process prepares methacrylic acid from isobutane by subjecting isobutane to a partial catalytic dehydrogenation in the gas phase and charging an oxidation zone with the isobutenic product gas mixture after the components other than isobutane and isobutene have been substantially removed from the product gas mixture. The oxygen required to charge the oxidation zone is introduced accompanied by nitrogen.Type: ApplicationFiled: December 29, 2003Publication date: December 2, 2004Inventors: Silki Berndt, Klaus Joachim Muller-Engel, Gotz-Peter Schindler, Frank Rosowski, Jochen Petzoldt
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Publication number: 20040242926Abstract: In a process for heterogeneously catalyzed partial gas phase oxidation of propene to acrylic acid, the starting reaction gas mixture is oxidized at a propene loading of <160 l(STP)/l·h in a first reaction stage over a fixed catalyst bed 1 which is accommodated in two successive reaction zones A, B, and the acrolein-containing product gas mixture of the first reaction stage is subsequently oxidized in a second reaction stage over a fixed catalyst bed 2 which is a accommodated in two successive reaction zones C, D, the highest temperature of the reaction gas mixture within reaction zone A being above the highest temperature of the reaction gas mixture within reaction zone B and the highest temperature of the reaction gas mixture within reaction zone C being above the highest temperature of the reaction gas mixture within reaction zone D.Type: ApplicationFiled: March 15, 2004Publication date: December 2, 2004Applicant: BASF AktiengesellschaftInventors: Martin Dieterle, Jochen Petzoldt, Klaus Joachim Muller-Engel, Heiko Arnold
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Publication number: 20040220427Abstract: An object of the invention is to provide a process in which Michael addition reaction products generated as by-products in a (meth)acrylic acid production step are pyrolyzed to enable high-purity (meth)acrylic acid to be recovered at a high recovery and troubles such as clogging in production steps are prevented.Type: ApplicationFiled: May 26, 2004Publication date: November 4, 2004Applicant: MITSUBISHI CHEMICAL CORPORATIONInventors: Shuhei Yada, Kenji Takasaki, Yasushi Ogawa, Yoshiro Suzuki
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Publication number: 20040210085Abstract: In an acrylic acid production process which comprises the step of producing acrylic acid by catalytic vapor-phase oxidation of propane, propylene, and/or acrolein; and purifying the acrylic acid produced in the step of producing with distillation in the presence of the polymerization inhibitor for preventing polymerization of the acrylic acid, a viscosity at 20° C. of the bottoms which comprises the polymerization inhibitor, discharged in the step of purifying, is adjusted to 2 Pa.s (2,000 cP) or less and the polymerization inhibitor is extracted using an aqueous medium.Type: ApplicationFiled: May 14, 2004Publication date: October 21, 2004Inventors: Shuhei Yada, Kenji Takasaki, Yasushi Ogawa, Yoshiro Suzuki
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Publication number: 20040199001Abstract: A process for preparing at least one partial oxidation and/or ammoxidation product of a hydrocarbon by partially dehydrogenating at least one saturated hydrocarbon H under heterogeneous catalysis and using the resulting product gas mixture A, which comprises the partially dehydrogenated hydrocarbon H, as such or in modified form for heterogeneously catalyzed partial oxidation and/or ammoxidation of the partially dehydrogenated hydrocarbon present in the product gas mixture A, said process including at least one mechanical separating operation inserted between the product gas mixture A and the heterogeneously catalyzed partial oxidation and/or ammoxidation.Type: ApplicationFiled: March 31, 2004Publication date: October 7, 2004Applicant: BASF AkiengesellschaftInventors: Gotz-Peter Schindler, Otto Machhammer, Klaus Joachim Muller-Engel, Claus Hechler, Jochen Petzoldt, Christoph Adami, Klaus Harth
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Publication number: 20040186303Abstract: A process for burning in a combustion chamber an exhaust gas containing oxygen and a combustible component, which exhaust gas originates from the heterogeneously catalyzed gas-phase oxidation of an inorganic or organic compound, by heating the exhaust gas to a temperature in the range from 200° C. to a temperature which corresponds to the hottest temperature in the heterogeneously catalyzed gas-phase oxidation and is above 200° C. and feeding the exhaust gas at this temperature to the burner head.Type: ApplicationFiled: January 29, 2004Publication date: September 23, 2004Inventor: Walter Schicketanz
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Publication number: 20040181090Abstract: A method for managing the operation of an apparatus for the reaction of gas phase partial oxidation of an unsaturated hydrocarbon with a molecular oxygen-containing gas for the purpose of omitting wasteful emergency stop of the operation and ensuring execution of necessary emergency measure and a method for producing (meth) acrylic acid by utilizing the method mentioned above are provided. The operation of the apparatus is brought to emergency stop exclusively when thee values of concentrations of various gases obtained by calculation from the flow rates of the gases being introduced at the inlet port of the reactor and the measured values obtained by analysis with gas analyzing instruments both deviate from the ranges of the present values.Type: ApplicationFiled: March 9, 2004Publication date: September 16, 2004Inventors: Kenji Sanada, Yukihiro Matsumoto, Takeshi Nishimura, Harunori Hirao
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Publication number: 20040171874Abstract: A method for producing (meth)acrolein and/or (meth)acrylic acid by subjecting isobutylene and the like or propylene to a vapor-phase catalytic oxidation with molecular oxygen in the presence of a solid oxidation catalyst in a tubular type of fixed bed reactor, wherein a temperature of a hot-spot zone is sufficiently controlled and (meth)acrolein and (meth)acrylic acid are produced with a high yield.Type: ApplicationFiled: April 20, 2004Publication date: September 2, 2004Inventors: Seigo Watanabe, Motomu Oh-Kita, Toshihiro Sato
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Patent number: 6780816Abstract: A modified carrier carrying on at least a part of an inert carrier surface an oxide which is represented by the formula (1): XaYbZcOd (wherein X is at least an element selected from alkaline earth metals; Y is at least an element selected from Si, Al, Ti and Zr; Z is at least an element selected from Group IA elements and Group IIIb elements of the periodic table, B, Fe, Bi, Co, Ni and Mn; and O is oxygen; a, b, c and d denote the atomic ratios of X, Y, Z and O, respectively, where a=1, 0<b≦100, 0≦c≦10, and d is a numerical value determined by the extents of oxidation of the other elements) is provided. A catalyst formed with the use of this modified carrier carrying a complex oxide containing Mo and V is useful as a vapor-phase catalytic oxidation catalyst, and is particularly suitable as a catalyst for preparing acrylic acid through vapor phase catalytic oxidation of acrolein.Type: GrantFiled: June 20, 2003Date of Patent: August 24, 2004Assignee: Nippon Shokubai Co., Ltd.Inventors: Michio Tanimoto, Hiromi Yunoki, Daisuke Nakamura
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Publication number: 20040138499Abstract: &agr;,&bgr;-ethylenically unsaturated aldehydes and/or carboxylic acids are prepared by means of a two-stage catalytic gas-phase oxidation in which a gas mixture comprising at least an alkane or alkene having from three to six carbon atoms and oxygen is subjected to a catalytic oxidation reaction, in the first stage (1). oxygen is added to the gases produced in the first stage (1) and the resulting mixture is introduced into the second stage (2) in which it is subjected to a further catalytic oxidation reaction. In the process of the present invention, a signal which correlates with the oxygen content of the reaction gases before and/or after the addition of oxygen between the first and second stages (1, 2) is generated and the oxygen addition is regulated as a function of the signal.Type: ApplicationFiled: October 9, 2003Publication date: July 15, 2004Inventors: Thomas Buschulte, Volker Diehl, Bernd Hagen, Volker Huth, Wolfgang Kasten, Peter Schlemmer, Axel Schroth
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Publication number: 20040122116Abstract: The present invention relates to a method for gas-solid contacting in a bubbling fluidized bed reactor by:Type: ApplicationFiled: December 2, 2003Publication date: June 24, 2004Applicant: COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCHInventors: Vasant Ramchandra Choudhary, Tushar Vasant Choudhary
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Publication number: 20040116731Abstract: A catalyst comprising a mixed metal oxide is useful for the vapor phase oxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated carboxylic acid and for the vapor phase ammoxidation of an alkane or a mixture of an alkane and an alkene to an unsaturated nitrile.Type: ApplicationFiled: November 25, 2003Publication date: June 17, 2004Inventors: Ann Mae Gaffney, Michele Doreen Heffner, Ruozhi Song
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Publication number: 20040116736Abstract: A process for the continuous recovery of (meth)acrylic acid from the reaction gas of a catalytic gas-phase oxidation comprising the following process stages is proposed:Type: ApplicationFiled: September 29, 2003Publication date: June 17, 2004Inventors: Otto Machhammer, Christoph Adami, Claus Hechler, Jurgen Schroder, Volker Schliephake, Joachim Thiel, Volker Diehl
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Patent number: 6747162Abstract: In a reactor (1) which has a bundle of catalyst tubes (2) and in which a heat transfer medium is circulated through the space surrounding the catalyst tubes, with the ring lines (3, 4) at both ends of the reactor with openings (5, 6) through the wall for introduction or removal of a heat transfer medium by means of one or more pumps, where the heat transfer medium is introduced into the lower ring line (4) and is returned via the upper ring line (3) to the pump(s) and the heat transfer medium or a substream of the heat transfer medium may, if desired, be passed over one or more external heat exchangers, and with deflecting plates (7) which alternately leave free an open cross section in the middle of the reactor and at the edge of the reactor, the lower ring line (4) is divided by means of a horizontal dividing wall (8) into two regions between which material can pass via preferably uniformly distributed openings (9) having a regulatable open cross section.Type: GrantFiled: November 14, 2002Date of Patent: June 8, 2004Assignee: BASF AktiengesellschaftInventors: Gerhard Olbert, Franz Corr
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Patent number: 6737546Abstract: Economical processes are disclosed for recovery and refining of at least acrylic acid from a gaseous mixture such as is obtainable by gas-phase catalytic oxidation of propylene. Processes of the invention include quenching the gaseous mixture with an aqueous quench liquid to obtain an aqueous solution comprising the acid values; contacting the aqueous solution with an immiscible extraction solvent; and an integrated sequence of distillations and phase separations to recover for recycle organic components of the extraction solvent, and obtain valuable acrylic acid and acetic acid products. Advantageously, the immiscible extraction solvent is substantially free of aromatic compounds such as benzene and toluene.Type: GrantFiled: November 13, 2001Date of Patent: May 18, 2004Assignee: Lurgi AGInventors: David R. Wagner, Steve J. Miko
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Publication number: 20040073063Abstract: In a process for preparing acrylic acid, an acrylic acid-containing product gas mixture obtained by catalytic gas phase partial oxidation of a C3 precursor of acrylic acid, after direct cooling with a quench liquid, is fractionally condensed in a separating column provided with internals, rising into itself with sidestream takeoff of crude acrylic acid, and the acrylic acid oligomers which form are dissociated and the resulting dissociation gas is subjected to a countercurrent rectification before it is recycled.Type: ApplicationFiled: June 20, 2003Publication date: April 15, 2004Applicant: BASF AktiengesellschaftInventors: Joachim Thiel, Ulrich Hammon, Dieter Baumann, Jorg Heilek, Juergen Schroder, Klaus Joachim Muller-Engel
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Publication number: 20040059155Abstract: This invention relates to a high load process for preparing (meth)acrylic acid from a reactive hydrocarbon using a high reactive hydrocarbon space velocity to provide increased capacity and throughput.Type: ApplicationFiled: August 1, 2003Publication date: March 25, 2004Inventors: Charles Michael Lonzetta, James Edward Elder, Peter David Klugherz, Timothy Allen Hale
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Publication number: 20040015014Abstract: A method for the production of acrylic acid comprises (i) a step for introducing a polymerization inhibitor to a stage other than a stage for supplying a raw material and a stage for supplying a reflux of said distilling column or (ii) a step for supplying the acrylic acid recovered by thermally decomposing said oligomer to said stage for dehydration. Thus, the present invention enjoys effective utilization of acrylic acid and exalts the efficiency of production.Type: ApplicationFiled: June 27, 2003Publication date: January 22, 2004Inventors: Takeshi Nishimura, Yukihiro Matsumoto, Kenji Sanada, Harunori Hirao
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Patent number: 6667419Abstract: A method for the absorption of (meth)acrylic acid and/or (meth)acrolein and an apparatus thereof which, in an absorption column adapted to cause an (meth)acrylic acid and/or (meth)acrolein-containing gas obtained in consequence of catalytic gas phase oxidation to come into countercurrent contact with a solvent, contemplate using a packing of relatively high efficiency in absorption disposed on the upstream side of the flow of a liquid containing the solvent and a packing and/or trays of relatively low performance of forming polymerization disposed on the downstream side thereof, in the column.Type: GrantFiled: June 28, 2000Date of Patent: December 23, 2003Assignee: Nippon Shokubai Co., Ltd.Inventors: Yukihiro Matsumoto, Takeshi Nishimura, Misao Inada, Kazuhiko Sakamoto
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Publication number: 20030233012Abstract: The production of ethylenically unsaturated acids or esters by the catalytic reaction of an alkanoic acid or ester, especially methyl propionate, with formaldehyde, and a catalyst therefor wherein the catalyst comprises a porous high surface area silica containing 1-10% by weight of an alkali metal, especially cesium (expressed as a metal) and having compounds of at least one modifier element selected from boron, magnesium, aluminium, zirconium and hafnium dispersed in the pores of said silica in such amount that the catalyst contains a total of 0.25 to 2 gram atoms of primary modifier element per 100 moles of silica.Type: ApplicationFiled: January 17, 2003Publication date: December 18, 2003Inventors: Samuel David Jackson, David William Johnson, John David Scott, Gordon James Kelly, Brian Peter Williams
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Patent number: 6664416Abstract: The present invention produces (meth)acrylic acid in a high yield in a process for producing (meth)acrylic acid by subjecting at least one member selected from the group consisting of (meth)acrolein, propane, and isobutane to catalytic gas phase oxidation with molecular oxygen or a molecular-oxygen-containing gas. In addition, the present invention makes it possible to produce (meth)acrylic acid in a high yield and stably for a long time. The present invention provides a process for producing (meth)acrylic acid by catalytic gas phase oxidation reaction, which is characterized by allowing a reaction gas to contain a reducible compound.Type: GrantFiled: April 6, 2002Date of Patent: December 16, 2003Assignee: Nippon Shokubai Co., Ltd.Inventors: Michio Tanimoto, Hiroto Kasuga
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Patent number: 6651731Abstract: For a heat exchanger using a heating medium for the purpose of heating a fluid to be handled during a steady state, this invention provides a method for using relevant devices which enables the heat exchanger to be operated safely and infallibly without suffering the raw material or the reaction product to polymerize in the reactor or the pipes during an unsteady state, suffering the reactor or the pipes to sustain a fracture owing to a rise in the internal pressure of the vessel, and suffering the apparatus for production to sustain serious damage. This invention pertains, mainly in a heat exchanger admitting a heating medium and using it for the purpose of heating a fluid to be handled, to a method for using relevant devices during the unsteady state, characterized by introducing a cooling medium in the place of the heating medium mentioned above.Type: GrantFiled: February 1, 2002Date of Patent: November 25, 2003Assignee: Nippon Shokubai Co., Ltd.Inventors: Takeshi Nishimura, Yukihiro Matsumoto, Sei Nakahara, Motomi Nakamura
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Patent number: 6646161Abstract: A process for the fractional condensation of a gas mixture which, in addition to acrylic acid or methacrylic acid, also contains at least one further condensable component and additionally a high proportion of one or more noncondensable components, wherein the gas mixture is passed through a column having separatory internals and the condensable components are condensed by cooling.Type: GrantFiled: March 13, 2000Date of Patent: November 11, 2003Assignee: BASF AktiengesellschaftInventors: Bernd Eck, Otto Machhammer, Theo Proll, Volker Schliephake, Joachim Thiel, Klaus Bröllos
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Patent number: 6632965Abstract: The present invention provides a process for producing acrolein and acrylic acid by the vapor-phase oxidation of propylene in the presence of Mo—Bi—Fe-based compound oxide catalysts packed in a fixed-bed multitubular reactor wherein acrolein and acrylic acid can be stably produced in high yield for a long period of time. This process is characterized in that each reaction tube having two or more reaction zones disposed along the axis of the tube is packed with catalysts having different ratios of the Bi and/or Fe content to the Mo content in such a way that the ratio decreases from the gas inlet side toward the gas outlet side.Type: GrantFiled: August 4, 2000Date of Patent: October 14, 2003Assignee: Nippon Shokubai Co. Ltd.Inventors: Michio Tanimoto, Hiromi Yunoki, Hideyuki Hironaka, Naomasa Kimura
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Publication number: 20030181621Abstract: A method for producing polyacrylic acid includes a combined process of an acrylic acid production process and a polyacrylic acid production process. The acrylic acid production process includes the steps of catalytically oxidizing propylene and/or propane in a gaseous phase to generate reaction product, absorbing the reaction product in a solvent, and purifying acrylic acid from an acrylic acid aqueous solution containing the solvent by purification. The polyacrylic acid production process includes the step of utilizing heat medium recovered in the acrylic acid production process to purify polyacrylic acid from the acrylic acid aqueous solution or from acrylic acid.Type: ApplicationFiled: February 28, 2003Publication date: September 25, 2003Inventors: Yukihiro Matsumoto, Sei Nakahara, Kunihiko Ishizaki
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Publication number: 20030181762Abstract: In a process for the preparation of acrolein or acrylic acid or a mixture thereof from propane, the propane is subjected, in a first reaction stage, to a partial dehydrogenation under heterogeneous catalysis to give propene, of the components contained in the product gas mixture formed in the first reaction stage other than propene and propane at least a portion of the molecular hydrogen present is then separated off from said mixture and the product gas mixture is then used for the preparation of acrolein and/or acrylic acid by gas-phase catalytic propylene oxidation, molecular nitrogen being present for diluting the reaction gas mixture during the propylene oxidation.Type: ApplicationFiled: December 13, 2002Publication date: September 25, 2003Inventors: Otto Machhammer, Goetz-Peter Schindler, Andreas Tenten, Klaus Harth, Peter Zehner, Klaus Joachim Muller-Engel, Frank Rosowski, Frieder Borgmeier
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Patent number: 6613940Abstract: In the reaction of catalytic gas phase oxidation by means of a shell-and-tube type reactor adapted to circulate a heating medium to the shell of the reactor through the medium of a circulation device connecting an annular conduit connected thereto, a method for the catalytic gas phase oxidation characterized by subjecting a part of the heating medium extracted from the shell of the reactor to heat exchange, introducing the heating medium resulting from the heat exchange into the proximity of a heating medium circulation inlet on the inlet side of the circulation device or the annular conduit on the outlet side of the reactor. The flow rate of the heating medium after the heat exchange is preferred to be in the range of 2-40 vol. % based on the flow rate of the heating medium within the shell of the reactor and the temperature difference of the heating medium at the inlet and the outlet to be in the range of 15-150° C.Type: GrantFiled: August 25, 2000Date of Patent: September 2, 2003Assignee: Nippon Shokubai Co., Ltd.Inventors: Takeshi Nishimura, Masakatsu Mori, Masatsugu Kitaura, Osamu Dodo, Daisuke Nakamura
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Publication number: 20030149300Abstract: The present invention relates to a preparation method of methacrylic acid which improves reaction selectivity of methacrylic acid. The method may include while producing methacrylic acid by gas phase of oxidation of oxidizing methachrolane in the presence of catalyst. Particularly, the present invention relates to the preparation method of methacrylic acid comprising the step of introducing CO2 up to 3˜80 mole % of the feed gas in the presence off catalyst having the general formula of PaMo11VbXcYdOe, wherein X is may be one or more elements selected from the group of alkaline metal and Tl element, Y is may be one or more elements selected from the group of Cu, Pb, Sb, Cr and Ce, and In addition, a, b, c, d and e is are the molar ratio of each necessary element when molybdenum is 11, where a is 0.8˜1.6, b is 0.6˜2, c is 0.8˜2.2, d is 0.1˜0.8 and e is a suitable value for elemental valency in the composition of said formula respectively.Type: ApplicationFiled: September 27, 2002Publication date: August 7, 2003Inventors: Ki-Hwa Lee, Jin-Su Yoo
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Publication number: 20030144550Abstract: An active and selective hydrocarbon partial oxidation catalyst comprises an activated partially-reduced polyoxometallate, preferably niobium polyoxomolybdate, that is prepared from a suitable polyoxoanion, which has been exchanged with a suitable cation and activated by heating to an activation effective temperature in the presence of a suitable reducing agent such as pyridinium. C3 and C4 hydrocarbons may be partially oxidized selectively to acrylic acid and maleic acid.Type: ApplicationFiled: November 1, 2002Publication date: July 31, 2003Inventors: Mark E. Davis, Christopher J. Dillon, Joseph H. Holles, Jay A. Labinger, Axel Brait
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Patent number: 6583316Abstract: Improved catalysts for use in vapor phase oxidation of at least one compound selected from the group consisting of propylene, isobutylene, t-butanol and methyl-t-butyl ether with molecular oxygen or a molecular oxygen-containing gas to produce the corresponding unsaturated aldehyde and unsaturated carboxylic acid are provided. The improved catalysts are compositions comprising (A) a complex oxide containing as essential components molybdenum, bismuth and iron, which is known per se as a catalyst for said reaction and (B) a complex oxide containing cerium and zirconium as the essential components. When the improved catalysts are used, the production operation of unsaturated aldehyde and unsaturated carboxylic acid can be continued stably for over prolonged period.Type: GrantFiled: May 11, 2000Date of Patent: June 24, 2003Assignee: Nippon Shokubai Co., Ltd.Inventors: Hideo Onodera, Michio Tanimoto
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Patent number: 6555707Abstract: A process for preparing acrylic acid and/or acrylates, which comprises stage A with or without stages B and C: A: cooling a gaseous reaction mixture which comprises acrylic acid and is obtained in the gas-phase oxidation to prepare acrylic acid, using an inert high-boiling solvent, to give a gaseous mixture comprising acrylic acid; B: separating the gaseous mixture comprising acrylic acid to give a low-boiling fraction, a crude acrylic acid, and a bottom product, and C: esterifying the crude acrylic acid obtained in stage B by means of one or more alkanols to give an esterification mixture comprising one or more acrylates and one or more acetic esters.Type: GrantFiled: September 22, 2000Date of Patent: April 29, 2003Assignee: BASF AktiengesellschaftInventors: Gerhard Nestler, Jürgen Schröder, Gerhard Bolz
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Patent number: 6541665Abstract: In a process for the purification of acrylic acid or methacrylic acid by crystallization and distillation, the following steps are carried out: (a) crystallization of a mixture containing the acrylic acid or methacrylic acid with formation of product crystals having a higher concentration of acrylic acid or methacrylic acid and of a mother liquor, (b) distillation of at least part of the mother liquor from step (a) with formation of a distillation residue, which is at least partly removed, and of a top product, (c) crystallization of at least part of the top product from step (b) with formation of a crystallization residue, which is removed, and of crystals and (d) recycling of the crystals from step (c) to the crystallization (a).Type: GrantFiled: January 2, 2001Date of Patent: April 1, 2003Assignee: BASF AktiengesellschaftInventors: Erik Bastiaensen, Bernd Eck, Joachim Thiel
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Publication number: 20030045752Abstract: Process for the oligomerization of one or more olefinically unsaturated monomers comprising three or more carbon atoms, at least one of these monomers consisting of a C3 to C30 aliphatic mono-olefin, which process comprises reacting the olefinically unsaturated monomer(s) under oligomerization conditions in the presence of an effective amount of a catalyst system based onType: ApplicationFiled: June 20, 2002Publication date: March 6, 2003Inventors: Eric Johannes Maria De Boer, Hendrikus Hyacinthus Deuling, Klaas L. Von Hebel, Bart Johan Ruisch, Arie Van Zon
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Patent number: 6525217Abstract: A process for the catalytic gas-phase oxidation of propene to acrylic acid, in which the reaction gas starting mixture is oxidized, with an increased propene loading, in a first reaction stage, over a first fixed-bed catalyst and then the acrolein-containing product gas mixture of the first reaction stage is oxidized, in a second reaction stage, with an increased acrolein loading, over a second fixed-bed catalyst, the catalyst moldings in both reaction stages having an annular geometry.Type: GrantFiled: August 30, 2001Date of Patent: February 25, 2003Assignee: BASF AktiengesellschaftInventors: Signe Unverricht, Heiko Arnold, Andreas Tenten, Ulrich Hammon, Hans-Peter Neumann, Klaus Harth
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Patent number: 6500982Abstract: This invention relates to a process for preparing (meth)acrylic acid, whereby turndown control is utilized to maintain optimal distillation column performance in the dehydration of aqueous (meth)acrylic acid to provide a (meth)acrylic acid solution.Type: GrantFiled: June 13, 2000Date of Patent: December 31, 2002Assignee: Rohm and Haas CompanyInventors: Timothy Allen Hale, Robert Michael Mason, Josefina Tseng Chapman, James Clarence Day, Chorng-Shyuan Tsay
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Publication number: 20020193632Abstract: The present invention produces (meth)acrylic acid in a high yield in a process for producing (meth)acrylic acid by subjecting at least one member selected from the group consisting of (meth)acrolein, propane, and isobutane to catalytic gas phase oxidation with molecular oxygen or a molecular-oxygen-containing gas. In addition, the present invention makes it possible to produce (meth)acrylic acid in a high yield and stably for a long time. The present invention provides a process for producing (meth)acrylic acid by catalytic gas phase oxidation reaction, which is characterized by allowing a reaction gas to contain a reducible compound.Type: ApplicationFiled: April 6, 2002Publication date: December 19, 2002Applicant: Nippon Shakubai Co., Ltd.Inventors: Michio Tanimoto, Hiroto Kasuga
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Patent number: 6492548Abstract: Processes are disclosed for the oxidation of alkanes such as, for example, propane, to form unsaturated carboxylic aldehydes and acids such as, for example, acrolein and acrylic acid. The processes utilize oxygen and recycle alkanes, e.g. propane, to the aldehyde reactor. The presence of the alkane-to-aldehyde reaction can enhance the efficiency of the processes.Type: GrantFiled: September 20, 2000Date of Patent: December 10, 2002Assignee: Union Carbide Chemicals & Plastics Technology CorporationInventors: Jonathan L Brockwell, Mark A Young, William G Etzkorn, Barbara K Warren, John M Maher
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Patent number: 6448438Abstract: A method for purifying acrylic acid, which comprises carrying out dehydration distillation of an aqueous solution of acrylic acid by means of a dehydration column, wherein a distillation column having a theoretical plate number of at least 3 plates is used as the dehydration column, and the operational temperature of a site corresponding to the second theoretical plate is adjusted to be from 50 to 78° C.Type: GrantFiled: January 28, 2000Date of Patent: September 10, 2002Assignee: Mitsubishi Chemical CorporationInventors: Shuhei Yada, Masahiko Yamagishi, Kouji Kasamatsu, Yasuyuki Sakakura, Kiyoshi Takahashi
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Publication number: 20020123647Abstract: A method for producing an unsaturated carboxylic acid comprises: (a) contacting, in a reaction zone, an alkane with a catalyst containing a mixed metal oxide, under conditions which produce a product gas comprising the unsaturated carboxylic acid, unreacted alkane and a product alkene; (b) recovering unreacted alkane and product alkene from the product gas; and (c) recycling the recovered unreacted alkane and product alkene to the reaction zone; wherein the mixed metal oxide consists of a material having the formulaType: ApplicationFiled: September 25, 2001Publication date: September 5, 2002Inventors: Leonard Edward Bogan, Daniel A. Bors, Fernando Antonio Pessoa Cavalcanti, Scott Han, Bradley Anson Jacobs, Frederick William Kaiser, Peter David Klugherz, Manhua Lin, Donald Lee Zolotorofe
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Patent number: 6441228Abstract: The present invention provides an apparatus for producing (meth)acrylic acid and a process for producing (meth)acrylic acid with this apparatus wherein the apparatus enables to produce (meth)acrylic acid stably for a long period of time by effectively inhibiting the polymerization of (meth)acrylic acid in its production process (for example, in a reboiler). At least a part of the apparatus is made of a nickel-chromium-iron alloy with a molybdenum content of 3 to 20 mass %, but not including 3 mass %, or with a molybdenum content of 1 to 4 mass % and a copper content of 0.5 to 7 mass %.Type: GrantFiled: December 12, 2000Date of Patent: August 27, 2002Assignee: Nippon Shokubai Co., Ltd.Inventors: Sei Nakahara, Kazuhiko Sakamoto, Yukihiro Matsumoto, Kenji Sanada, Masatoshi Ueoka
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Patent number: 6433222Abstract: A process for the preparation of acrylic acid by: (a) preparation of a gaseous product mixture which essentially has the composition of a reaction mixture of catalytic gas-phase oxidation of C3-alkanes, C3-alkenes, C3-alkanols and/or C3-alkanals and/or intermediates thereof to acrylic acid, which comprises (b) condensation of the gaseous product mixture, (c) crystallization of the acrylic acid from the solution obtained in stage (b), with partial evaporation of the solution under reduced pressure, (d) isolation of the resulting crystals from the mother liquor, (e) recycling of at least a part of the mother liquor from stage (d) to stage (b) and (f) recycling of at least a part of the evaporated solution from stage (c) to stage (b).Type: GrantFiled: January 22, 2001Date of Patent: August 13, 2002Assignee: BASF AktiengesellschaftInventors: Bernd Eck, Jörg Heilek, Volker Schliephake, Theo Proll, Klaus Bröllos, Otto Machhammer, Joachim Thiel
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Patent number: 6426433Abstract: In a process for the preparation of acrolein and/or acrylic acid from propane, the propane is subjected, in a first reaction stage, to a partial oxydehydrogenation with molecular oxygen under homogeneous and/or heterogeneous catalysis to give propene and the product gas mixture formed in the first reaction stage is then used for the preparation of acrolein and/or acrylic acid by gas-phase catalytic propene oxidation.Type: GrantFiled: February 20, 2001Date of Patent: July 30, 2002Assignee: BASF AktiengesellschaftInventors: Otto Machhammer, Andreas Tenten, Harald Jachow, Susanne Haupt, Heiko Arnold, Signe Unverricht
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Patent number: 6407287Abstract: In a method for producing acrylic acid by the steps of a reaction of catalytic gas phase oxidation, absorbing the acrylic acid with an absorbent, and dehydrating the acrylic acid-containing aqueous solution, the method is characterized that the step of dehydration comprises adding and an azeotropic solvent, distilling the resultant mixture, and adjusting the acrylic acid concentration at the top of the column in the range of 0.06-0.80 wt. %, thereby preventing the bottoms of the azeotropic dehydration column from substantially containing the azeotropic solvent and water. As results, the acrylic acid is kept from forming a polymer in any of the distillation columns involved in the production, and effective utilization of acrylic acid.Type: GrantFiled: March 7, 2001Date of Patent: June 18, 2002Assignee: Nippon Shokubai Co., Ltd.Inventors: Yukihiro Matsumoto, Takeshi Nishimura, Kazuhiko Sakamoto, Hidefumi Haramaki
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Publication number: 20020072628Abstract: A process for preparing a metal oxide catalyst for acrylic acid production which comprises calcining a metal compound mixture at 400° C. or higher to prepare a metal oxide powder comprising Mo, V, Sb, and at least one element selected from the group consisting of Nb and Ta, and supporting a compound comprising at least one element selected from the group consisting of Sb, Tl, Se, As, Pb, Sn, Ag, Cu, Ru, and Rh on the metal oxide powder, and a process for producing acrylic acid by gas phase oxidation of propane using the catalyst.Type: ApplicationFiled: October 30, 2001Publication date: June 13, 2002Applicant: TOAGOSEI CO., LTD.Inventors: Xinlin Tu, Mamoru Takahashi, Hiroshi Niizuma
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Patent number: 6399817Abstract: This invention relates to a process for preparing acrylic acid which utilizes an aqueous stream which includes recycled wastewater, at least part of which is stripped of undesirable components in a stripping column prior to being recycled to an acrylic acid absorber.Type: GrantFiled: March 1, 2000Date of Patent: June 4, 2002Assignee: Rohm and Haas CompanyInventors: Josefina Tseng Chapman, James Clarence Day, Donald Alan Ebert, Thomas Albert Kaminski, Robert Michael Mason, Chorng-Shyuan Tsay
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Patent number: 6388129Abstract: In a process for the preparation of acrolein and/or acrylic acid from propane, the propane is subjected, in a first reaction stage, to a partial oxydehydrogenation with molecular oxygen under homogeneous and/or heterogeneous catalysis to give propene and the product gas mixture formed in the first reaction stage is then used for the preparation of acrolein and/or acrylic acid by gas-phase catalytic propene oxidation.Type: GrantFiled: February 20, 2001Date of Patent: May 14, 2002Assignee: BASF AktiengesellschaftInventors: Otto Machhammer, Andreas Tenten, Harald Jachow, Susanne Haupt, Heiko Arnold, Signe Unverricht
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Patent number: 6384274Abstract: This invention relates to an improved process for preparing acrylic acid from propylene using a single reactor utilizing an increased amount of propylene reactant thereby providing increased capacity and throughput.Type: GrantFiled: February 4, 1999Date of Patent: May 7, 2002Assignee: Rohm and Haas CompanyInventors: James Edward Elder, Charles Michael Lonzetta, Timothy Allen Hale, John Dempster Sornson, Peter David Klugherz, Thomas Albert Kaminski, Donald Alan Ebert
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Patent number: 6291686Abstract: An exothermic oxidation process wherein a rotating bed containing a variable oxidation state material is cycled through a succession of stages including an oxidative regeneration stage including a step wherein an oxidising fluid is passed through the bed, and a reaction stage wherein feedstock is passed through the bed, whereby said feedstock is oxidised to give products stream with the concurrent reduction of the convertible material to its lower oxidation state. The process can further include a stage wherein cooling fluid is passed through the bed.Type: GrantFiled: March 22, 2000Date of Patent: September 18, 2001Assignee: Imperial Chemical Industries PLCInventors: Samuel David Jackson, Frank King, David Graham Shipley, Edmund Hugh Stitt
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Publication number: 20010021788Abstract: In a method for producing acrylic acid by the steps of a reaction of catalytic gas phase oxidation, absorbing the acrylic acid with an absorbent, and dehydrating the acrylic acid-containing aqueous solution, the method is characterized that the step of dehydration comprises adding and an azeotropic solvent, distilling the resultant mixture, and adjusting the acrylic acid concentration at the top of the column in the range of 0.06-0.80 wt. %, thereby preventing the bottoms of the azeotropic dehydration column from substantially containing the azeotropic solvent and water. As results, the acrylic acid is kept from forming a polymer in any of the distillation columns involved in the production, and effective utilization of acrylic acid.Type: ApplicationFiled: March 7, 2001Publication date: September 13, 2001Inventors: Yukihiro Matsumoto, Takeshi Nishimura, Kazuhiko Sakamoto, Hidefumi Haramaki