Producing Unsaturated Acid Patents (Class 562/532)
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Patent number: 7524987Abstract: A process for preparing acrolein, or acrylic acid or a mixture thereof as a target product from propane, in which propane is partially dehydrogenated under heterogeneous catalysis in a reaction zone A, molecular hydrogen thus formed is incinerated partly to water and the product gas A thus formed in reaction zone A is used without secondary component removal to charge a reaction zone B in which propylene present in product gas A is partially oxidized to the target product. From the product gas B formed in reaction zone B, the target product is removed and the residual gas I remaining after an aftertreatment comprising a CO2 scrubbing and a partial discharge thereof is recycled into reaction zone A.Type: GrantFiled: August 18, 2006Date of Patent: April 28, 2009Assignee: BASF AktiengesellschaftInventors: Otto Machhammer, Klaus Joachim Müller-Engel, Martin Dieterle
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Patent number: 7518015Abstract: A process for heterogeneously catalyzed gas phase partial oxidation of an organic starting compound over a fixed catalyst bed freshly installed into a reaction chamber, in which the reduction in the quality of the fixed catalyst bed is restored with increasing operating time by replacing a portion of the fixed catalyst bed by a replacement fixed catalyst bed part whose volume-specific activity is lower than the volume-specific activity of the replaced fixed catalyst bed part in its freshly installed state.Type: GrantFiled: December 19, 2006Date of Patent: April 14, 2009Assignee: BASF AktiengesellschaftInventors: Ulrich Cremer, Ulrike Wegerle, Gerhard Laqua, Ulrich Hammon, Klaus Joachim Mueller-Engel
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Patent number: 7511172Abstract: A method for producing acrylic acid by absorbing acrylic acid at a high ratio and obtaining an acrylic acid-containing solution of high concentration is provided. This method comprises a step of circulating part of a discharged gas from an absorption step of acrylic acid to the reactor and discarding the remainder to the out side of system while the gas is cooled before circulation to the reactor. By the method, the acrylic acid-containing solution of high concentration is obtained due to decrease of an acrylic acid loss.Type: GrantFiled: July 23, 2007Date of Patent: March 31, 2009Assignee: Nippon Shokubai Co., Ltd.Inventors: Harunori Hirao, Kouji Ueno, Naoki Serata, Takeshi Yokogoshiya
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Publication number: 20090068440Abstract: The present invention relates to a process for the production of acrolein, comprising the following steps: (a) bringing into contact of an aqueous glycerine phase in an acrolein reaction area to obtain an aqueous acrolein reaction phase; (b) depleting the acrolein from the acrolein reaction phase to obtain an acrolein phase and a depleted acrolein reaction phase; (c) conducting back at least a part of the depleted acrolein reaction phase into the acrolein reaction area. The invention further relates to a process for production of acrylic acid as well as of water-absorbing polymer structures, composites, in particular hygiene articles, comprising these water-absorbing polymer structures, a process for production of the composites and further chemical products based on the acrylic acid obtained by the inventive process and also the use of this acrylic acid in chemical products.Type: ApplicationFiled: June 16, 2005Publication date: March 12, 2009Inventors: Gunther Bub, Jurgen Mosler, Andreas Sabbagh, Franz-Felix Kuppinger, Guido Stochniol, Jorg Sauer, Jorg Leistner, Gunter Latoschinski, Thorsten Schwatzke
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Patent number: 7488845Abstract: A method for the safe operation of a continuously operated heterogeneously catalyzed gas-phase partial oxidation of an organic compound in a reactor, the composition of the feed gas mixture being controlled by pressure-controlled concentration determination of relevant constituents.Type: GrantFiled: November 1, 2006Date of Patent: February 10, 2009Assignee: BASF AktiengesellschaftInventors: Claus Hechler, Peter Schlemmer
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Publication number: 20080300414Abstract: A process for recharging the reaction tubes of a tube bundle reactor with a new fixed catalyst bed, in which a heterogeneously catalyzed partial gas phase oxidation of an organic compound had been performed beforehand in a preceding fixed catalyst bed comprising Mo-comprising multielement oxide active compositions to form a steam-comprising product gas mixture, in which, before the recharge, solid deposit which had been deposited on the tube inner walls and comprises molybdenum oxide and/or molybdenum oxide hydrate is brushed away with the aid of a brush.Type: ApplicationFiled: May 30, 2008Publication date: December 4, 2008Applicant: BASF SEInventors: Volker SCHLIEPHAKE, Klaus BOTT, Rolf-Dieter BECHER, Klaus Joachim MULLER-ENGEL, Jochen PETZOLDT, Ulrich CREMER, Andreas RAICHLE
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Publication number: 20080293968Abstract: A catalyst for the production of methacrylic acid comprising a heteropolyacid compound containing phosphorus and molybdenum is regenerated by a method comprising the steps of drying a mixture containing a deactivated catalyst, an ammonium ion, a nitrate ion and water, molding the dried mixture, firstly calcining the molded product in an atmosphere of an oxidizing gas at a temperature of 360 to 410° C., and then secondly calcining the product in an atmosphere of a non-oxidizing gas at a temperature of 420 to 500° C. The regenerated catalyst has substantially the same catalytic activity as a fresh catalyst in a gas phase catalytic oxidation reaction of methacrolein, isobutylaldehyde, isobutane or isobutyric acid to prepare methacrylic acid.Type: ApplicationFiled: October 11, 2007Publication date: November 27, 2008Inventors: Junya Yoshizawa, Yoshihiko Ohishi, Eiichi Shiraishi
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Publication number: 20080269521Abstract: A process for starting-up a heterogeneously catalyzed partial gas phase oxidation of acrolein to acrylic acid or of methacrolein to methacrylic acid over a fixed catalyst bed disposed in a tube bundle reactor cooled by a heat exchange medium, wherein the temperature of the heat exchange medium is ?290° C. and the temperature of that reactor plate surface which faces the reaction gas entry mixture and the temperature of the reaction gas entry mixture itself are ?285° C.Type: ApplicationFiled: April 22, 2008Publication date: October 30, 2008Applicant: BASF SEInventors: Ulrich HAMMON, Thorsten Friese, Jochen Petzoldt, Klaus Joachim Muller-Engel, Ulrich Cremer, Andreas Raichle
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Publication number: 20080242815Abstract: The invention provides a process which enables, in preparation of acrolein by catalytic gas-phase oxidation of propylene in the presence of molecular oxygen or a molecular oxygen-containing gas or in preparation of acrylic acid by catalytic gas-phase oxidation of acrolein in the presence of molecular oxygen or a molecular oxygen-containing gas, using single kind of atalyst, to suppress occurrence of localized extraordinarily high temperature spots (hot spots) in the catalyst layer and can stably maintain high acrolein or acrylic acid yield for a long time. The process is characterized by use of an oxide catalyst containing molybdenum as an essential component and having relative standard deviation of its particle size in a range of 0.02 to 0.20.Type: ApplicationFiled: March 28, 2008Publication date: October 2, 2008Inventor: Naohiro Fukumoto
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Patent number: 7429678Abstract: There are disclosed a catalyst and a process for production of acrylic acid using this catalyst, wherein, even under conditions where hot spots are formed, the catalyst is excellent in activity, selectivity, and catalyst life time and displays stable performances for a long time.Type: GrantFiled: January 26, 2004Date of Patent: September 30, 2008Assignee: Nippon Shokubai Co., Ltd.Inventors: Michio Tanimoto, Harunori Hirao
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Patent number: 7414149Abstract: The non-routine (e.g., emergency) shutdown of a chemical reaction process is achieved by a method of safely operating a chemical reaction process which comprises the steps of detecting an undesirable condition capable of affecting the process, minimizing the reaction of the reactants, and maintaining a flow of materials through the reaction zones of the process such that the reaction mixture is displaced from the reaction zones. The flow of materials may be maintained for a period of time such that the substantially all of the reaction mixture is displaced from the reaction zones, thereby flushing the reaction zones. The reaction mixture may then be purged to an ancillary vessel, such as an absorber.Type: GrantFiled: November 7, 2005Date of Patent: August 19, 2008Assignee: Rohm and Haas CompanyInventors: Michael Stanley DeCourcy, Nam Quoc Le
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Publication number: 20080194869Abstract: A system and process for separating methacrolein (MA) from methacrylic acid (MAA) and acetic acid in the gas phase product from partial oxidation of isobutylene (IB) in two oxidation steps is disclosed. The process and system maximize recovery of all three components at minimum capital and energy cost, under conditions that minimize polymerization conditions and plugging by solids deposition in compressors, columns, etc.Type: ApplicationFiled: February 14, 2007Publication date: August 14, 2008Inventor: Frederick Merrill Galloway
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Publication number: 20080177105Abstract: A process for preparing shaped catalyst bodies whose active composition is a multielement oxide, in which a finely divided precursor mixture with addition of graphite having a specific particle size is shaped to the desired geometry and then treated thermally.Type: ApplicationFiled: January 17, 2008Publication date: July 24, 2008Applicant: BASF SEInventors: Andreas Raichle, Frank Rosowski, Sabine Huber, Ulrich Cremer, Stefan Altwasser, Klaus Joachim Mueller-Engel
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Patent number: 7332139Abstract: Reactions between at least two fluid reactants are performed in a reactor comprising wall elements (1), slot-shaped reaction spaces (3) and cavities (5) for conducting a fluid heat-carrier through. Depending on the process and throughput, a modular structural design is chosen wherein an arbitrary number of wall elements (1) are assembled to a right-parallelepipedal block (24), the reaction spaces (3) are formed between lateral surfaces (2) of right-parallelepipedal wall elements (1), the reactants are introduced into the reaction spaces (3) from edge regions of one side of the block (24) and are conducted through the reaction spaces (3) in parallel flows and the fluid heat-carrier is conducted through the tubular cavities (5) extending in the interior of the wall elements (1).Type: GrantFiled: August 22, 2001Date of Patent: February 19, 2008Assignee: Degussa AGInventors: Rüdiger Schütte, Torsten Balduf, Catrin Becker, Ina Hemme, Birgit Bertsch-Frank, Werner Wildner, Jürgen Rollmann, Georg Markowz
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Patent number: 7332624Abstract: 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: GrantFiled: June 27, 2003Date of Patent: February 19, 2008Assignee: Nippon Shokubai Co., Ltd.Inventors: Takeshi Nishimura, Yukihiro Matsumoto, Kenji Sanada, Harunori Hirao
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Patent number: 7326811Abstract: A shell-and-tube type heat exchanger of the smallest possible length necessary for heat exchange is disclosed which is capable of obtaining uniform distribution of flow of a shell side fluid and substantially eliminating the structural restriction imposed on the shell side. This shell-and-tube type heat exchanger is provided with one annular conduit furnished with not less than two partitions concurrently serving as an expansion joint for introducing and discharging a shell side fluid and allowing the flow path for said shell side fluid to be separated into an introducing part and a discharging part and which comprises a place having no array of heat-transfer tubes in the flow path for said shell side fluid. It prevents the equipment from necessitating an unnecessary enlargement due to the structural restriction on the shell side and enables the shell side fluid to produce a uniform flow.Type: GrantFiled: October 20, 2006Date of Patent: February 5, 2008Assignee: Nippon Shokubai Co., Ltd.Inventors: Tetsuji Mitsumoto, Takeshi Nishimura, Sei Nakahara, Osamu Dodo
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Patent number: 7326810Abstract: In the reaction of catalytic gas phase oxidation induced by the supply of at least a raw material to be oxidized and a molecular oxygen-containing gas to a reactor for catalytic gas phase oxidation, a method for starting up the reactor for catalytic gas phase oxidation is disclosed which is characterized by causing the raw material and the molecular oxygen-containing gas to pass a range in which the concentration of the raw material is less than the lower explosion limit of the raw material and the concentration of oxygen is not less than the limiting oxygen concentration, but excluding the concentration of the raw material of 0 vol. %. The method enables the reactor to be started up economically and safely by avoiding the explosion range induced by the composition of a raw material and a molecular oxygen-containing gas supplied to the reactor and decreasing the amount of a diluting gas to be supplied.Type: GrantFiled: July 31, 2001Date of Patent: February 5, 2008Assignee: Nippon Shokubai Co., Ltd.Inventors: Harunori Hirao, Yukihiro Matsumoto, Sei Nakahara, Kunihiko Suzuki
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Patent number: 7321060Abstract: A method for the production of acrylic acid of high concentration by absorbing acrylic acid with high absorption ratio of acrylic acid is provided. In a method for producing acrylic acid by a procedure comprising a step of catalytic gas phase oxidation reaction and a step of absorbing the acrylic acid-containing gas, while a low boiling substance-containing solution is introduced into the absorption column via a portion different from the top of the column.Type: GrantFiled: June 2, 2004Date of Patent: January 22, 2008Assignee: Nippon Shokubai Co., Ltd.Inventors: Naoki Serata, Kouji Ueno, Harunori Hirao, Takeshi Yokogoshiya
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Patent number: 7304179Abstract: The present invention provides a method for producing methacrylic acid through gas-phase catalytic oxidation of methacrolein or a methacrolein-containing gas with molecular oxygen or a gas containing molecular oxygen by the use of a fixed-bed multitubular reactor comprising a plurality of reaction tubes each having a catalyst layer therein, wherein the above catalyst layer is divided in the direction of the tube axis of a reaction tube into two or more layers, to thereby provide a plurality of reaction zones, and the catalyst is caused to be present in the catalyst layer in such a way that a reaction load ratio CRc(i) per unit mass of the catalyst in each reaction zone becomes 0.8 to 1.0.Type: GrantFiled: August 27, 2004Date of Patent: December 4, 2007Assignee: Mitsubishi Rayon Co., Ltd.Inventors: Tomomichi Hino, Akira Ogawa
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Patent number: 7300555Abstract: A process for rectificatively separating liquids containing (meth)acrylic monomers in a rectification column is provided, in which a stream is withdrawn from the rectification column and recycled into the rectification column as a molecular oxygen-enriched liquid phase.Type: GrantFiled: November 17, 2003Date of Patent: November 27, 2007Assignee: BASF AktiengesellschaftInventor: Juergen Schroeder
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Patent number: 7297814Abstract: A multitube reactor, wherein tubes having smaller tolerance between a nominal size and actual sizes are used as reaction tubes to stably perform a high yield reaction for a long period, a catalyst is filled into the reaction tubes so that the catalyst layer peak temperature portions of the reaction tubes are not overlapped with the connection sites thereof with baffles to effectively prevent hot spots from occurring and stably perform a reaction for a long period without the clogging of the reaction tubes, a heat medium and raw material gas are allowed to flow in the direction of a countercurrent and a specified type of catalyst is filled into the reaction tubes so that activity is increased from the inlet of the raw material gas to the outlet thereof to prevent the autooxidation of products so as to prevent equipment from being damaged due to the reaction, and, at the time of starting, gas with a temperature of 100 to 400° C.Type: GrantFiled: February 3, 2005Date of Patent: November 20, 2007Assignee: Mitsubishi Chemical CorporationInventors: Shuhei Yada, Hirochika Hosaka, Masayasu Goriki, Kimikatsu Jinno, Yasushi Ogawa, Yoshiro Suzuki
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Patent number: 7294734Abstract: This invention relates to a process for converting a hydrocarbon reactant to a product comprising an oxygenate or a nitrile, the process comprising: (A) flowing a reactant composition comprising the hydrocarbon reactant, and oxygen or a source of oxygen, and optionally ammonia, through a microchannel reactor in contact with a catalyst to convert the hydrocarbon reactant to the product, the hydrocarbon reactant undergoing an exothermic reaction in the microchannel reactor; (B) transferring heat from the microchannel reactor to a heat exchanger during step (A); and (C) quenching the product from step (A).Type: GrantFiled: May 2, 2003Date of Patent: November 13, 2007Assignee: Velocys, Inc.Inventors: John H. Brophy, Frederick A. Pesa, Anna Lee Tonkovich, Jeffrey S. McDaniel, Kai Tod Paul Jarosch
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Patent number: 7258766Abstract: A method for collecting acrylic acid is provided, which includes the step of collecting acrylic acid using an aqueous medium from a reaction gas containing acrylic acid obtained by catalytic vapor-phase oxidation of propane, propylene, and/or acrolein, the step being conducted so as to satisfy the following formula (1) (B/A)<1.25 (1) wherein A represents a weight fraction of acrylic acid to all condensable ingredients in the reaction gas before collecting acrylic acid and B represents a weight fraction of acrylic acid in bottoms of a collection device used in the step of collecting. According to the method, acrylic acid can be efficiently collected from the reaction gas containing acrylic acid obtained by catalytic vapor-phase oxidation.Type: GrantFiled: April 21, 2004Date of Patent: August 21, 2007Assignee: Mitsubishi Chemical CorporationInventors: Shuhei Yada, Kimikatsu Jinno, Yasushi Ogawa, Yoshiro Suzuki
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Patent number: 7253308Abstract: A process for the continuous gas-phase oxidation of C3- and C4-precursors to (meth)acrolein and/or (meth)acrylic acid in the presence of a catalyst in a reactor which has a feed for the reaction mixture at one reactor end and removal of the reaction mixture at the opposite reactor end and which is equipped with means, arranged in the interior of the reactor, for removing the heat of reaction, through which means a heat exchange composition flows and which means are in the form of heat exchanger plates, is proposed.Type: GrantFiled: November 3, 2000Date of Patent: August 7, 2007Assignee: BASF ActiengesellschaftInventors: Claus Hechler, Otto Machhammer, Gerhard Olbert, Uwe Stabel, Peter Zehner
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Patent number: 7253309Abstract: This invention is related to a shell-and-tube type reactor provided with reaction tubes packed with a catalyst and adapted to circulate a heat medium to the fluid outside the tubes and is characterized by a method introducing a gas into the catalyst beds so as to retain the relative humidity of the catalyst in the range of more than 40% while elevating the temperature of the reactor thereby starting up the reactor. This method prevents the catalyst from degradation of activity due to absorption of moisture, exalts the service life of the catalyst, and permits stable production of methacrylic acid.Type: GrantFiled: January 29, 2003Date of Patent: August 7, 2007Assignee: Nippon Shokubai Co., LtdInventors: Hiroyuki Uhara, Kazuo Anyouji, Hideyuki Hironaka, Hideo Onodera
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Patent number: 7238827Abstract: Process for preparing at least one partial oxidation and/or ammoxidation product of propylene, in which the propylene is produced from crude propane by dehydrogenation and is subjected to a heterogeneously catalyzed gas-phase partial oxidation and/or partial gas-phase ammoxidation in the presence of unreacted propane as constituent of a gas mixture 2 containing <1% by volume of 1-butene.Type: GrantFiled: June 20, 2003Date of Patent: July 3, 2007Assignee: BASF AktiengesellschaftInventors: Claus Hechler, Götz-Peter Schindler, Jochen Petzoldt, Christoph Adami, Otto Machhammer, Klaus Joachim Müller-Engel, Hans Martan
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Patent number: 7214821Abstract: A process is proposed for preparing (meth)acrolein and/or (meth)acrylic acid by partially oxidizing C3 and/or C4 precursor compounds in the gas phase in the presence of a heterogeneous particulate catalyst, in a reactor having two or more thermoplates (1) arranged vertically and parallel to each other while in each case leaving a gap (2), the heterogeneous particulate catalyst being installed in the gaps (2) and the gaseous reaction mixture being passed through the gaps (2), which comprises monitoring, controlling and/or regulating the process by selecting as a monitoring, control and/or regulation parameter one or more temperatures which are measured in one or more gaps (2), at one or more measurement points which are distributed over the height of each gap (2).Type: GrantFiled: December 23, 2004Date of Patent: May 8, 2007Assignee: BASF AktiengesellschaftInventors: Claus Hechler, Gerhard Olbert, Dietmar Loewen
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Patent number: 7211692Abstract: A process for the long-term operation of a two-stage heterogeneously catalyzed gas phase partial oxidation of propene to acrylic acid, in which the temperature of the fixed catalyst beds is increased over the time and the gas phase partial oxidation is interrupted from time to time and an oxygen-containing gas mixture is conducted through the fixed catalyst beds at elevated temperature of the fixed catalyst beds.Type: GrantFiled: October 12, 2004Date of Patent: May 1, 2007Assignee: BASF AktiengesellschaftInventors: Martin Dieterle, Jochen Petzoldt, Klaus Joachim Mueller-Engel
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Patent number: 7196217Abstract: Process for operating a continuous heterogeneously catalyzed gas phase partial oxidation of at least one organic compound using compressed air as the oxygen source which is filtered before its compression.Type: GrantFiled: August 6, 2004Date of Patent: March 27, 2007Assignee: BASF AktiengesellschaftInventors: Volker Schliephake, Ulrich Hammon, Rolf-Dieter Becher, Klaus Joachim Muller-Engel
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Patent number: 7183428Abstract: A method for producing acrylic acid by using an acrylic acid-containing solution of high concentration without azeotropic distillation is provided. This method of producing acrylic acid comprises introducing an acrylic acid-containing gas obtained by catalytic gas phase oxidation reaction into an absorption column and supplying the acrylic acid-containing solution to crystallization step thereby separating the solution into acrylic acid and residual mother liquid, and distilling at least part of the residual mother liquid and circulating the distillate obtained by the distillation to the absorption column.Type: GrantFiled: June 2, 2004Date of Patent: February 27, 2007Assignee: Nippon Shokubai Co., Inc.Inventors: Kouji Ueno, Harunori Hirao, Naoki Serata, Takeshi Yokogoshiya
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Patent number: 7179875Abstract: In a process for preparing water-absorbent resins based on acrylic acid, crude acrylic acid is firstly isolated from the reaction gases from the catalytic gas-phase oxidation of propane, propylene and/or acrolein. This is treated with an aldehyde scavenger and pure acrylic acid is separated by distillation from the treated crude acrylic acid, and this pure acrylic acid can be subjected directly to a free-radical polymerization.Type: GrantFiled: August 2, 2002Date of Patent: February 20, 2007Assignee: BASF AktiengesellschaftInventors: Eberhard Fuchs, Hans Martan, Gerhard Nestler, Klaus Joachim Mueller-Engel
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Patent number: 7176335Abstract: A process prepares methacrolein from isobutane by subjecting isobutane to a partial catalytic dehydrogenation in the gas phase and using the isobutenic product gas mixture to charge an oxidation zone in which the isobutene is oxidized to methacrolein in the gas phase with heterogeneous catalysis using molecular oxygen accompanied by molecular nitrogen as the oxygen source.Type: GrantFiled: June 28, 2002Date of Patent: February 13, 2007Assignee: BASF AktiengesellschaftInventors: Silke Berndt, Klaus Joachim Mueller-Engel, Goetz-Peter Schindler, Frank Rosowski, Jochen Petzoldt
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Patent number: 7147048Abstract: A shell-and-tube type heat exchanger of the smallest possible length necessary for heat exchange is disclosed which is capable of obtaining uniform distribution of flow of a shell side fluid and substantially eliminating the structural restriction imposed on the shell side. This shell-and-tube type heat exchanger is provided with one annular conduit furnished with not less than two partitions concurrently serving as an expansion joint for introducing and discharging a shell side fluid and allowing the flow path for said shell side fluid to be separated into an introducing part and a discharging part and which comprises a place having no array of heat-transfer tubes in the flow path for said shell side fluid. It prevents the equipment from necessitating an unnecessary enlargement due to the structural restriction on the shell side and enables the shell side fluid to produce a uniform flow.Type: GrantFiled: September 25, 2002Date of Patent: December 12, 2006Assignee: Nippon Shokubai Co., LtdInventors: Tetsuji Mitsumoto, Takeshi Nishimura, Sei Nakahara, Osamu Dodo
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Patent number: 7144557Abstract: A multitube reactor, wherein tubes having smaller tolerance between a nominal size and actual sizes are used as reaction tubes to stably perform a high yield reaction for a long period, a catalyst is filled into the reaction tubes so that the catalyst layer peak temperature portions of the reaction tubes are not overlapped with the connection sites thereof with baffles to effectively prevent hot spots from occurring and stably perform a reaction for a long period without the clogging of the reaction tubes, a heat medium and raw material gas are allowed to flow in the direction of a countercurrent and a specified type of catalyst is filled into the reaction tubes so that activity is increased from the inlet of the raw material gas to the outlet thereof to prevent the autooxidation of products so as to prevent equipment from being damaged due to the reaction, and, at the time of starting, gas with a temperature of 100 to 400° C.Type: GrantFiled: July 12, 2004Date of Patent: December 5, 2006Assignee: Mitsubishi Chemical CorporationInventors: Shuhei Yada, Hirochika Hosaka, Masayasu Goriki, Kimikatsu Jinno, Yasushi Ogawa, Yoshiro Suzuki
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Patent number: 7119227Abstract: The present invention provides a process for catalytic vapor phase oxidation which prevents runaway reaction or early deterioration of a catalyst, in the production of (meth)acrylic acid or the like from propylene or isobutylene by the catalytic vapor phase oxidation process using a multi-tubular reactor, which can lead to the production thereof constantly in high yield for a long period of time.Type: GrantFiled: September 10, 2004Date of Patent: October 10, 2006Assignee: Mitsubishi Chemical CorporationInventors: Yasuyuki Sakakura, Shuhei Yada, Kimikatsu Jinno, Hirochika Hosaka, Yoshiro Suzuki
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Patent number: 7109374Abstract: 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: I quenching of the reaction gas by evaporative cooling using a high-boiling solvent, II separation of the (meth)acrylic acid from the quenched reaction gas by absorption into the high-boiling solvent, III separation of the solvent laden with (meth)acrylic acid by rectification into a first part-stream IIIA), which contains predominantly (meth)acrylic acid, and into a second part-stream IIIB) which contains predominantly the solvent, IV recycling of the stream IIIB) to process stage II and V distillative production of (meth)acrylic acid from stream IIIA), all liquid residual streams obtained in process stage V being recycled to process stage I.Type: GrantFiled: March 28, 2002Date of Patent: September 19, 2006Assignee: BASF AktiengesellschaftInventors: Otto Machhammer, Christoph Adami, Claus Hechler, Juergen Schroeder, Volker Schliephake, Joachim Thiel, Volker Diehl
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Patent number: 7074955Abstract: A continuously operated heterogeneously catalyzed gas-phase partial oxidation of at least one organic compound in an oxidation reactor is operated safely by a process in which an explosion diagram for the feed gas mixture is deposited as the basis of a cut-out mechanism in a computer.Type: GrantFiled: June 12, 2003Date of Patent: July 11, 2006Assignee: BASF AktiengesellschaftInventors: Ulrich Hammon, Jochen Meschke, Ulrich Rauh, Klaus Joachim Müller-Engel, Peter Schlemmer, Volker Schliephake
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Patent number: 7045657Abstract: The object of the present invention is to provide a process in which, when the unsaturated carboxylic acid is produced, or when the unsaturated aldehyde and/or the unsaturated carboxylic acid are produced by carrying out the catalytic gas phase oxidation reaction by using the fixed-bed multitubular reactor which is packed with the molybdenum-containing catalyst, the reaction can be continued for a long time while a high yield is maintained, regardless of where the hot spot portion occurs and also even if the concentration of the raw gas is high.Type: GrantFiled: March 12, 2003Date of Patent: May 16, 2006Assignee: Nippon Shokubai Co., Ltd.Inventors: Hiromi Yunoki, Michio Tanimoto
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Patent number: 7045482Abstract: The present invention relates to a method for preparing a heteropolyacid catalyst and method for preparing methacrylic acid using thereof. More particularly, the present invention relates to a method for preparing heteropolyacid catalyst, which is produced by the recrystallization of a heteropolyacid and/or its salt dissolved in a basic organic solvent and heat-treatment, and further to a method for preparing metachrylic acid using thereof, wherein the use of the heteropolyacid catalyst increases the activity of oxidation reaction induced by the modified electronic properties of heteropolyanions and provides high efficiency production of methacrylic acid from methacrolein, since the basic property of solvent inhibits peculiar acidic property of heteropolyacid.Type: GrantFiled: June 3, 2003Date of Patent: May 16, 2006Assignee: Korea Institute of Science and TechnologyInventors: Myung-Suk Chun, In Kyu Song, Suk Woo Nam
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Patent number: 7038080Abstract: A process for the heterogeneously catalyzed gas-phase partial oxidation of acrolein to acrylic acid over a multimetal oxide material having a specific structure, which contains the elements Mo and V, at least one of the elements Te and Sb and at least one of the elements from the group consisting of Nb, Ta, W and Ti and is doped with promoter elements, is described.Type: GrantFiled: September 23, 2003Date of Patent: May 2, 2006Assignee: BASF AktiengesellschaftInventors: Martin Dieterle, Frieder Borgmeier, Klaus Joachim Mueller-Engel, Hartmut Hibst
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Patent number: 7030269Abstract: There are disclosed: a catalyst which can be used for production of acrylic acid and is excellent in the catalytic performances (e.g. conversion of starting material, selectivity of aimed product) and further has very high physical strength; and a process for production of acrylic acid using this catalyst. The above catalyst for production of acrylic acid is a catalyst which is obtained by a process including the steps of: heating a mixed liquid of starting materials including molybdenum and vanadium as essential components; and then molding the resultant dried material with a liquid binder; and then calcining the resultant molding; with the catalyst being characterized in that the liquid binder is an aqueous liquid of 7.0 to 10.0 in pH.Type: GrantFiled: October 13, 2003Date of Patent: April 18, 2006Assignee: Nippon Shokubai Co., Ltd.Inventors: Hiromi Yunoki, Michio Tanimoto
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Patent number: 7022877Abstract: A process for the long-term operation of a heterogeneously catalyzed gas phase partial oxidation of acrolein to acrylic acid, in which the temperature of the fixed catalyst bed is increased over time and partial oxidation is interrupted and an oxygen-containing gas is conducted through the fixed catalyst bed before the temperature increase is 8° C.Type: GrantFiled: October 13, 2004Date of Patent: April 4, 2006Assignee: BASF AktiengesellschaftInventors: Martin Dieterle, Jochen Petzoldt, Klaus Joachim Müller-Engel
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Patent number: 7012156Abstract: The present invention relates to a preparation method of methacrylic acid which improves reaction selectivity of methacrylic acid. The method may include producing methacrylic acid by gas phase oxidation of 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. X may be one or more elements selected from the group of alkaline metal and Tl element. Y may be one or more elements selected from the group of Cu, Pb, Sb, Cr and Ce. In addition, a, b, c, d and e 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: GrantFiled: December 20, 2000Date of Patent: March 14, 2006Assignee: Samsung General Chemicals, Co., Ltd.Inventors: Ki-Hwa Lee, Jin-Sun Yoo
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Patent number: 7005544Abstract: A method for effectively preventing polymerization of acrylic acid during an azeotropic dehydration distillation in an acrylic acid manufacturing process and thus enabling stable operation of the azeotropic dehydration column over an extended period of time. The acrylic acid is separated in an azeotropic dehydration column from an acrylic acid aqueous solution fed therein, and the method includes withdrawing from the bottom of the azeotropie dehydration column a bottom effluent containing 50% or more of glyoxal (including the hydrates thereof) contained in the acrylic acid aqueous solution fed into the azeotropic dehydration column.Type: GrantFiled: August 29, 2003Date of Patent: February 28, 2006Assignee: Nippon Shokubai Co., Ltd.Inventors: Kazuo Ohkouchi, Tomohiro Nakae, Kazuhiko Sakamoto
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Patent number: 6982347Abstract: In a process for partially oxidizing acrolein to acrylic acid in the gas phase under heterogeneous catalysis, the starting reaction gas mixture is oxidized at an acrolein loading of ?145 and ?70 l (STP) of acrolein/l of fixed catalyst bed·h over a fixed catalyst bed which is accommodated in two successive reaction zones A, B, 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.Type: GrantFiled: March 23, 2004Date of Patent: January 3, 2006Assignee: BASF AktiengesellschaftInventors: Martin Dieterle, Jochen Petzoldt, Klaus Joachim Müller-Engel, Heiko Arnold
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Patent number: 6969774Abstract: In a method for synthesizing methacrylic acid by using a fixed bed tube type reactor provided with a catalyst bed into which a solid oxidation catalyst is filled and with a heat medium bath and by flowing a raw material gas containing methacrolein and oxygen through the catalyst bed, the catalyst bed does not have any sections in which a temperature difference between the heat medium bath and the catalyst bed (?T) exceeds 35° C., and two or more high temperature zones in which each ?T is 15 to 35° C. are provided. According to this method, mathacrylic acid can be manufactured in higher yields.Type: GrantFiled: December 7, 2000Date of Patent: November 29, 2005Assignee: Mitsubishi Rayon Co., Ltd.Inventors: Seigo Watanabe, Motomu Oh-Kita
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Patent number: 6949675Abstract: The present invention provides a process for producing acrylic acid, by which process the problem, such that the catalyst placed on the gas inlet side deteriorates faster than that placed on the gas outlet side, is solved, so that the catalyst can be used stably for a long time.Type: GrantFiled: August 27, 2002Date of Patent: September 27, 2005Assignee: Nippon Shokubai Co., Ltd.Inventor: Hiromi Yunoki
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Patent number: 6939991Abstract: 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: GrantFiled: June 20, 2003Date of Patent: September 6, 2005Assignee: BASF AktiengesellschaftInventors: Joachim Thiel, Ulrich Hammon, Dieter Baumann, Jörg Heilek, Jürgen Schröder, Klaus Joachim Müller-Engel
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Patent number: 6930201Abstract: In a method of producing methacrylic acid by passing a material gas containing methacrolein, oxygen and water vapor through a reactor packed with a catalyst containing as the main component a compound oxide containing molybdenum and phosphorus, a concentration of methacrolein in the material gas is controlled in a range of 4 to 6.5 vol %, a molar ratio of the water vapor to the methacrolein in the material gas is controlled in a range of 1 to 2, and a space velocity of the material gas to the catalyst-packed layer is controlled in a range of 500 to 750 h?1, whereby deterioration of the catalyst is effectively inhibited.Type: GrantFiled: December 19, 2001Date of Patent: August 16, 2005Assignee: Mitsubishi Rayon Co., Ltd.Inventors: Seigo Watanabe, Motomu Oh-Kita
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Patent number: 6927307Abstract: This invention provides a method of reactivating a catalyst for methacrylic acid production, which catalyst is used in production of methacrylic acid through vapor-phase oxidation of methacrolein or vapor-phase oxidative dehydrogenation of isobutyric acid, contains P and Mo, and exhibits reduced activity. The process comprises treating the catalyst, whose activity level has dropped (deteriorated catalyst), with a gas containing a nitrogen-containing heterocyclic compound (e.g., pyridine, piperidine, piperazine, quinoline).Type: GrantFiled: August 28, 2003Date of Patent: August 9, 2005Assignee: Sumitomo Chemical Co., Ltd.Inventors: Hiroto Kasuga, Eiichi Shiraishi