Preparation By Dehalogenation Patents (Class 562/604)
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Patent number: 10155714Abstract: The present invention pertains to a process for the purification of a feed comprising monochloroacetic acid and dichloroacetic acid wherein the feed is subjected to a catalytic hydrodechlorination step by contacting it with a source of hydrogen to convert dichloroacetic acid into monochloroacetic acid in the presence of a solid heterogeneous hydrogenation catalyst comprising a Group VIII noble metal on a carrier under hydrodechlorination conditions, wherein the reaction is carried out in the presence of a catalyst enhancer which comprises a salt of a metal selected from the group of non-noble metals of Group VIII, Group VIB, Group VIIB, and Group IIB. It was found that the presence of a catalyst enhancer leads to reduced deactivation of the catalyst and/or increased activity of the spent catalyst. This allows longer production cycles, less downtime, and lower formation of side products.Type: GrantFiled: March 14, 2016Date of Patent: December 18, 2018Assignee: AKZO NOBEL CHEMICALS INTERNATIONAL B.V.Inventors: Lars Magnus Tollin, Melle Rinze Nieuwhof, Arie Grootenboer, Jacobus Theodorus Josef Aaldering, Henricus Johannes Marinus Petrus Van Hal, Matheus Theodorus De Groot
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Patent number: 10131611Abstract: The present invention is directed to a process for catalytic hydrodechlorination of dichloroacetic acid, wherein hydrogen gas is contacted with a liquid feed comprising dichloroacetic acid and monochloroacetic acid to form a product stream comprising monochloroacetic acid and an off gas stream comprising hydrogen chloride and hydrogen, and wherein the product stream is contacted with nitrogen gas so as to remove hydrogen gas present in the product stream.Type: GrantFiled: June 9, 2016Date of Patent: November 20, 2018Assignee: Akzo Nobel Chemicals International B.V.Inventors: Lars Magnus Tollin, Cornelis Kooijman
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Patent number: 9505694Abstract: The present invention pertains to a process for the purification of a substantially water-free liquid feed comprising monochloroacetic acid, dichloroacetic acid, optionally acid chlorides, optionally anhydrides, and optionally acetic acid, which comprises the steps of (a) adding water to the liquid feed so that a liquid feed is obtained comprising between 0.01 and 5% by weight of water, based on the total weight of the liquid feed, and (b) subsequently subjecting the liquid feed obtained in step (a) to a catalytic hydrodechlorination step by contacting it with a source of hydrogen to convert the dichloroacetic acid into monochloroacetic acid in the presence of a solid heterogeneous hydrogenation catalyst comprising one or more metals of Group VIII of the Periodic Table of the Elements deposited on a carrier.Type: GrantFiled: October 17, 2012Date of Patent: November 29, 2016Assignee: Akzo Nobel Chemicals International B.V.Inventors: Melle Rinze Nieuwhof, Cornelis Kooijman, Willem Koelewijn, Hendrik Jan Vos, Lars Magnus Tollin, Henricus Johannes Marinus Petrus Van Hal
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Publication number: 20140357892Abstract: The process of the present invention pertains to a process wherein a liquid feed comprising monochioroacetic acid, dichloroacetic acid, and optionally acetic acid and/or trichioroacetic acid is subjected to a catalytic hydrodechlorination step by contacting it with a source of hydrogen in the presence of a solid heterogeneous hydrogenation catalyst situated in a fixed catalyst bed, wherein the liquid feed is fed to the top of avertical tubular reactor at a superficial mass velocity of between and 10 kg/s per square meter of the horizontal cross-section of the vertical tubular reactor and a rate of between 250 and 3,000 kg/hr per m of said catalyst bed, wherein the source of hydrogen is fed to the top or bottom of the vertical tubular reactor at a rate of between 0.025 to 0.Type: ApplicationFiled: October 17, 2012Publication date: December 4, 2014Applicant: AKZO NOBEL CHEMICALS INTERNATIONAL B.V.Inventors: Melle Rinze Nieuwhof, Cornelis Kooijman, Hendrik Jan Vos, Lars Magnus Tollin, Jacobus Van Den Berg, Henricus Johannes Marinus Petrus Van Hal
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Publication number: 20140275625Abstract: The present invention pertains to a process for the purification of a substantially water-free liquid feed comprising monochloroacetic acid, dichloroacetic acid, optionally acid chlorides, optionally anhydrides, and optionally acetic acid, which comprises the steps of (a) adding water to the liquid feed so that a liquid feed is obtained comprising between 0.01 and 5% by weight of water, based on the total weight of the liquid feed, and (b) subsequently subjecting the liquid feed obtained in step (a) to a catalytic hydrodechlorination step by contacting it with a source of hydrogen to convert the dichloroacetic acid into monochloroacetic acid in the presence of a solid heterogeneous hydrogenation catalyst comprising one or more metals of Group VIII of the Periodic Table of the Elements deposited on a carrier.Type: ApplicationFiled: October 17, 2012Publication date: September 18, 2014Applicant: AKZO NOBEL CHEMICALS INTERNATIONAL B.V.Inventors: Melle Rinze Nieuwhof, Cornellis Kooijman, Willem Koelewijn, Hendrik Jan Vos, Lars Magnus Tollin, Henricus Johannes Marinus Petrus Van Hal
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Patent number: 8101798Abstract: A process for the manufacture of substantially pure monochloroacetic acid from a liquid chloroacetic acid mixture comprising monochloroacetic acid and dichloroacetic acid, in particular in an amount of 2 to 40 percent by weight, wherein said mixture, further mixed with a suspended hydrogenation catalyst, is mixed with hydrogen gas and the resulting mixture is brought to reaction in a reactor, which is characterized in that the reactor is a loop reactor comprising a gas and liquid recirculation system coupled via an ejector mixing nozzle, in which reactor the gas and liquid are circulated in co-current flow, and the mixing intensity introduced to the liquid phase is at least 50 W/l of liquid phase.Type: GrantFiled: August 28, 2007Date of Patent: January 24, 2012Assignee: Buss Chemtech AGInventors: Roxana Stoenescu Timmermans, Gerhard Kettenbach
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Publication number: 20100029984Abstract: A process for the manufacture of substantially pure monochloroacetic acid from a liquid chloroacetic acid mixture comprising monochloroacetic acid and dichloroacetic acid, in particular in an amount of 2 to 40 percent by weight, wherein said mixture, further mixed with a suspended hydrogenation catalyst, is mixed with hydrogen gas and the resulting mixture is brought to reaction in a reactor, which is characterized in that the reactor is a loop reactor comprising a gas and liquid recirculation system coupled via an ejector mixing nozzle, in which reactor the gas and liquid are circulated in co-current flow, and the mixing intensity introduced to the liquid phase is at least 50 W/l of liquid phase.Type: ApplicationFiled: August 28, 2007Publication date: February 4, 2010Inventors: Roxana Stoenescu Timmermans, Gerhard Kettenbach
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Patent number: 6906219Abstract: The invention relates to a method for preparing bromodifluoroacetic compounds which comprises converting a 1,1-difluoro-1,2-dibromodihaloethane with oleum having 50-70% SO3 to a bromodifluoroacetyl halide (bromide or chloride) and then in reacting the latter directly with either an alcohol, or with water.Type: GrantFiled: June 18, 2002Date of Patent: June 14, 2005Assignee: AtofinaInventors: Gilles Drivon, Jean-Philippe Gillet, Christophe Ruppin
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Patent number: 6509495Abstract: The invention concerns a selective hydrodehalogenation method characterised in that it comprises a step which consists in contacting a substrate including a sp 3 hybridisation carbon atom bearing an electro-attracting group and at least a fluorine atom, and a halogen atom heavier than fluorine, with a reagent comprising: an aqueous phase, a base, a group VIII metal as hydrogenation catalyst, and hydrogen dissolved in the aqueous phase, at a concentration in equilibrium with a gas phase whereof the partial pressure in hydrogen is not less than 50 kPa, advantageously ranging between 50 kPa and 2.10 7 Pa. The invention is applicable to organic synthesis.Type: GrantFiled: July 19, 2001Date of Patent: January 21, 2003Assignee: Rhodia ChimieInventors: Georges Cordier, Roland Jacquot
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Patent number: 5756840Abstract: The present invention relates to a process for the preparation of a particularly pure monochloroacetic acid, in which, in a first step, a hydrogenation of a mixture of mono- and dichloroacetic acid is carried out to a residual content of dichloroacetic acid of 400 to 600 ppm and, in a second step, this mixture is subjected to melt crystallization. The hydrogenation is carried out with a heterogeneous catalyst which comprises 0.1-5.0% by weight of palladium and in which active charcoal or silicon dioxide is used as the support.Type: GrantFiled: December 11, 1996Date of Patent: May 26, 1998Assignee: Hoechst AktiengesellschaftInventors: Frank Ebmeyer, Detlef Kampmann, Ulf Otto Paulus-Von Russdorf, Rudolf Rossmeissl
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Patent number: 5455376Abstract: Aliphatic .omega.-difluorocarboxyl compounds are prepared in an economic manner from aliphatic .omega.-monohalogeno-difluorocarboxyl compounds by bringing the latter into contact with hydrogen in the presence of a catalyst which is applied to an inert support material and comprises one or more metals of group VIII of the Periodic Table at 120.degree. to 250.degree. C.Type: GrantFiled: December 5, 1994Date of Patent: October 3, 1995Assignee: Bayer AktiengesellschaftInventor: Dietmar Bielefeldt
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Patent number: 5191118Abstract: The alpha-halogenated carboxylic acids/esters are dehalogenated by reaction with hydrogen in the presence of a catalytically effective amount of (i) a Group VIII precious metal catalyst and (ii) either sulfur or a sulfur compound, or (iii) a novel precious metal/sulfur solid phase catalyst; the subject dehalogenation is especially adapted for enriching the monochloroacetic acid content of MCAA/DCAA mixtures.Type: GrantFiled: April 6, 1990Date of Patent: March 2, 1993Assignee: AtochemInventors: Yves Correia, Michel Bertucci
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Patent number: 4172957Abstract: Continuous process for the production of monochloroacetyl chloride accompanied, if the need should arise, by monochloroacetic acid, from trichloroethylene and/or 1,1,1,2-tetrachloroethane by reaction for hydration of trichloroethylene and/or 1,1,1,2-tetrachloroethane under pressure of hydrogen chloride in liquid phase, in the presence of ferric chloride in partial suspension.Type: GrantFiled: July 12, 1978Date of Patent: October 30, 1979Assignee: Rhone-Poulenc IndustriesInventors: Yves Correia, Gerard Dumas
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Patent number: 4141895Abstract: 6-Substituted-2-halofluoromethyl-1,2-dihydro-2-hydroxy-1-methyl-4-phenylqui nazolines and their use as intermediates in the preparation of 3-fluorobenzodiazepines, which are useful as tranquilizers, muscle relaxants and sedatives.Type: GrantFiled: June 16, 1977Date of Patent: February 27, 1979Assignee: E. I. Du Pont de Nemours and CompanyInventor: William J. Middleton