Alkali Metal Hydroxide Patents (Class 203/37)
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Patent number: 10975011Abstract: A method for forming a blend of ethers from a blend of alcohols includes a step of reacting a hydrocarbon-containing gas with an oxygen-containing gas to form first product blend. The first product blend includes a blend of partially oxygenated compounds. The blend of partially oxygenated compounds is provided to a reactive distillation station where it is converted a second product blend. The second product blend typically includes a mixture of ethers. An apparatus implementing the method is also provided.Type: GrantFiled: March 4, 2019Date of Patent: April 13, 2021Assignee: GAS TECHNOLOGIES LLCInventors: Ian Lawrence Gaffney, Evan Michael Visser, Krishna K. Rao, Walter Breidenstein
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Patent number: 10913029Abstract: A method, scrubbing solution and apparatus for removing a H2S scavenger, for example dithiazine, from a gas stream uses an acidic solution to convert the H2S scavenger to a salt. The acidic solution may be a phosphoric acid solution.Type: GrantFiled: February 14, 2020Date of Patent: February 9, 2021Assignee: Canadian Energy Services L.P.Inventor: David Horton
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Patent number: 10237938Abstract: A drive circuit is configured to drive a light emitting unit which is provided in a vehicle lamp and includes a plurality of semiconductor light emitting elements connected in series. The drive circuit includes a drive voltage generation unit configured to reduce an input voltage from a battery to generate a drive voltage for driving the semiconductor light emitting elements, and a control unit configured to perform ON/OFF control for a bypass switch connected in parallel to a part of the semiconductor light emitting elements and to perform interlock dimming control when the input voltage becomes a first threshold value or lower. The interlock dimming control selects a dimming mode and increases an ON ratio per unit time of the bypass switch as the input voltage drops in the dimming mode.Type: GrantFiled: May 8, 2018Date of Patent: March 19, 2019Assignee: KOITO MANUFACTURING CO., LTD.Inventor: Tomoyuki Ichikawa
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Patent number: 10099171Abstract: A gas capture plant is provided. The gas capture plant includes an absorption tower for dissolving an object gas that requires regeneration in a lean absorbent liquid to produce rich absorbent liquid. A regeneration tower heats the rich absorbent liquid produced in the absorption tower to produce the lean absorbent liquid from which the regeneration gas is separated and the produced lean absorbent liquid is supplied back to the absorption tower. A gas condensing device condenses the regeneration gas received from the regeneration tower to separate condensate and target gas, thereafter, supplying the separated condensate to the regeneration tower, and exhausting the separated target gas. The gas condensing device includes a condenser and a reflux apparatus disposed within one housing and the condenser is disposed above the reflux apparatus.Type: GrantFiled: December 2, 2015Date of Patent: October 16, 2018Assignees: Hyundai Motor Company, Korea Institute of Energy ResearchInventors: Shin-Tae Bae, Sungchan Nam, Sungyeoul Park, Yeoil Yoon
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Patent number: 9850324Abstract: The present invention is directed to a process for preparing epoxidized polymers. The process comprises reacting an unsaturated polymer with hydrogen peroxide in the presence of a polymer support having a sulfonic acid group. The present invention is also directed to an epoxidized halogenated-polymer which comprises repeating units derived from at least one isoolefin monomer and repeating units derived from at least one diolefinic monomer, and one or more allylic halide groups and one or more oxirane functional groups in the polymer backbone.Type: GrantFiled: December 11, 2013Date of Patent: December 26, 2017Assignee: LANXESS, Inc.Inventors: Paul Nguyen, Gregory J. E. Davidson, Richard Samuel Steevensz
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Patent number: 9505690Abstract: An apparatus includes an airtight shell and an absorption column arranged inside the shell. The absorption column has a multiple stage component, and a single stage component arranged below the multiple stage component with respect to gravity. A gap is arranged between the multiple stage component and the single stage component. The apparatus also includes a gas input in fluid communication with the absorption column for receiving a gas mixture, and a liquid input is in fluid communication with the absorption column for receiving a liquid mixture. A liquid-liquid separator is arranged below the absorption column with respect to gravity. The gas input is arranged below the single stage component. The liquid input is arranged above the single stage component and below the multiple stage component. A method is described for using the apparatus to remove DME from gas and liquid mixtures.Type: GrantFiled: May 15, 2014Date of Patent: November 29, 2016Assignee: Shell Oil CompanyInventor: Hendrik Adriaan Kooijman
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Publication number: 20140238841Abstract: A method of producing 2,3-butanediol includes subjecting a 2,3-butanediol culture liquid produced by microbial fermentation to nanofiltration membrane treatment and ion-exchange treatment (Step A), and then adding an alkaline substance and performing distillation (Step B).Type: ApplicationFiled: October 12, 2012Publication date: August 28, 2014Applicant: Toray Industries, Inc.Inventors: Kenji Kawamura, Izumi Morita, Masateru Ito, Kyohei Isobe, Satoshi Sakami, Katsushige Yamada
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Publication number: 20140183030Abstract: N-alkylpyrrolidone and, as contaminant alongside this, the corresponding N-alkyl-succinimide, to give a pure solvent stream which meets the requirements for use in a process for the production of polymers, where compounds of higher and lower boiling point than the N-alkylpyrrolidone are removed by distillation, which comprises, prior to, during, or after the distillative purification process, adding a hydroxide of an alkali metal or of an alkaline earth metal in a molar amount corresponding to a molar ratio of at least 0.1:1 for this hydroxide with respect to the respective N-alkylsuccinimide in the appropriate solvent stream present prior to, during, or after the distillative purification process.Type: ApplicationFiled: December 26, 2013Publication date: July 3, 2014Applicant: BASE SEInventors: Christoph Sigwart, Jörg Erbes, Martin Weber, Gerhard Lange, Jutta Vonend, Cornelis Hendricus De Ruiter
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Publication number: 20130153401Abstract: A process for purifying a brine of organic compounds comprising: (a) supplying a brine that comprises at least one organic compound; (b) feeding at least one stripping zone with the brine from (a) and at least one stripping agent; (c) withdrawing from the stripping zone at least one fraction (I) consisting essentially of brine, the content of the organic compound being lower in fraction (I) than in the brine from step (a), and at least one fraction (II) consisting essentially of the stripping agent; wherein the temperature (T1) of the hotter fraction of the two fractions (I) and (II) and the temperature (T2) of the colder fraction of the two fractions (I) and (II), such temperatures expressed in degrees Celsius being the temperatures measured before any possible thermal conditioning which might be carried out before and/or during their withdrawal from the stripping zone, correspond to the following formula: 6×10?7(T1)3.Type: ApplicationFiled: August 22, 2011Publication date: June 20, 2013Applicant: SOLVAY SAInventors: Patrick Gilbeau, Philippe Krafft, Jerome Ligot, Valentine Smets, Giancarlo Iavarone
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Patent number: 8298378Abstract: A method for treating a wastewater containing oxygen-containing compound having a phenolic hydroxyl group or a carbonyl group, including a step of adding an alkali agent to the wastewater containing the oxygen-containing compound having a phenolic hydroxyl group or a carbonyl group to control a pH of the wastewater to 10 or more; and a step of separating a discharge in which the oxygen-containing compound having a phenolic hydroxyl group or a carbonyl group is concentrated through distillation of the wastewater to which the alkali agent has been added.Type: GrantFiled: March 24, 2006Date of Patent: October 30, 2012Assignee: Sumitomo Chemical Company, LimitedInventor: Kenji Itoh
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Patent number: 8231765Abstract: A method and a plant are disclosed for purifying lactams, particularly lactams obtained by cyclizing hydrolysis of aminonitrile. The purification of ?-caprolactam obtained by cyclizing hydrolysis of aminocapronitrile is described which includes eliminating the ammonia from the reaction medium of the hydrolysis, then recovering the lactam from the medium in purified form. The recovery is carried out by performing at least a distillation of the lactam in the presence of a base producing optionally a fronts fraction having compounds more volatile than the lactam, a fraction having the lactam to be recovered to the degree of desired purity and a distillation tails having the lactam and compounds less volatile than the lactam. The distillation tails are treated by various processes such as evaporation in thin layers to recover the major part of the caprolactam and recycling the latter in the purification process.Type: GrantFiled: May 29, 2008Date of Patent: July 31, 2012Assignee: Rhodia Polyamide IntermediatesInventors: Daniel Amoros, Philippe Leconte, Pierre Coqueret
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Patent number: 8163138Abstract: A method for processing effluent from a chloromethylation of a vinyl aromatic polymer wherein the effluent includes catalyst and volatile organics, and wherein the method includes the steps of: 1) deactivating at least a portion of the catalyst; 2) distilling the effluent; 3) adding caustic to the effluent; and 4) distilling the effluent.Type: GrantFiled: May 23, 2007Date of Patent: April 24, 2012Assignee: Dow Global Technologies LLCInventors: William I. Harris, Bruce S. Holden, Doreen C. Keptner, David C. McDonald
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Publication number: 20110214981Abstract: In a process for distillation, in a distillation column, of a crude stream of methanol produced from synthesis gas, fusel oil is removed from the distillation column as a vapour side draw from a point in the distillation column below the feed, and the vapour side draw is substantially free of alkali. A process for the production of methanol utilising this distillation process is also described.Type: ApplicationFiled: August 28, 2009Publication date: September 8, 2011Applicant: DAVY PROCESS TECHNOLOGY LIMITEDInventor: Simon Robert Early
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Patent number: 7985867Abstract: A process for producing epoxides, the process including: (a) feeding at least one aqueous alkali and at least one halohydrin to a reactive distillation column, wherein the reactive distillation column includes a feed zone, a top zone disposed above the feed zone, and a bottom zone disposed below the feed zone; (b) concurrently in the reactive distillation column: (i) reacting at least a portion of the halohydrin with the alkali to form an epoxide; and (ii) stripping water and the epoxide from a basic aqueous residue; (c) recovering the water and the epoxide from the reactive distillation column as an overheads fraction; (d) condensing and phase separating the overheads fraction to form an organic overheads fraction including the epoxide and an aqueous overheads fraction including water; and (e) maintaining a liquid holdup per plate in the feed zone at a residence time of 10 seconds or less.Type: GrantFiled: July 23, 2009Date of Patent: July 26, 2011Assignee: Dow Global Technologies LLCInventors: William W. Fan, Christian D. Kneupper, Sascha Noormann, Renate Patrascu
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Publication number: 20100140076Abstract: Disclosed is a method for processing a waste water containing an oxygen-containing compound having a phenolic hydroxyl group or a carbonyl group, which comprises the following first step and second step. First step: An alkaline agent is added into a waste water containing an oxygen-containing compound having a phenolic hydroxyl group or a carbonyl group so that the waste water has a pH of not less than 10. Second step: The waste water to which the alkaline agent is added in the first step is distilled for separating a waste liquid in which the oxygen-containing compound having a phenolic hydroxyl group or a carbonyl group is concentrated.Type: ApplicationFiled: March 24, 2006Publication date: June 10, 2010Applicant: Sumitomo Chemical Company, Ltd.Inventor: Kenji Itoh
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Patent number: 7615137Abstract: A continuous process is provided for recovering caprolactam from aqueous caprolactam product which includes (i) caprolactam, (ii) impurities, and (iii) water by (a) adding alkali hydroxide to the aqueous caprolactam product, in an amount of not more than 100 mmol alkali hydroxide per kg of caprolactam; (b) reacting at least part of the added alkali hydroxide to form alkali amino caproate, to obtain a caproate-enriched caprolactam product; and (c) distilling the caproate-enriched caprolactam product at reduced pressure.Type: GrantFiled: August 23, 2002Date of Patent: November 10, 2009Assignee: DSM IP Assets B.V.Inventors: Arnold G M Jetten, Nicolaas F Haasen, Gerardus W A Hangx
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Patent number: 7601245Abstract: The invention relates to a process for reducing the aldehyde concentration in a mixture comprising cyclohexanone and one or more aldehydes, said process comprising distilling said mixture in a distillation column in the presence of an alkaline compound, wherein in the bottom of the distillation column substantially no water is present.Type: GrantFiled: December 22, 2003Date of Patent: October 13, 2009Assignee: DSM IP Assets B.V.Inventors: Arno H Benneker, Augustinus P H Schouteten, Larry W Wyatt
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Patent number: 7541427Abstract: An objective of the present invention is to provide a desolvation method for removing a solvent efficiently from a polymer solution. In the present desolvation method where the solvent is removed from the polymer solution by steam stripping using an apparatus comprising a pipe which connects a gas phase portion of a desolvation tank at the downstream and a liquid phase portion of a desolvation tank at the upstream, and an opening-degree adjusting mean (for example, pressure adjusting valve) fixed to this pipe, pressures are controlled such that a pressure difference (?P=P2?P1) between pressures of each gas phase portion of desolvation tanks at the downstream and at the upstream is allowed to be larger by from 0.005 to 0.6 MPa, preferably from 0.05 to 0.3 MPa than a pressure difference when the opening-degree adjusting mean is fully opened.Type: GrantFiled: June 14, 2004Date of Patent: June 2, 2009Assignees: JSR Corporation, International Center for Environmental Technology TransferInventors: Nobuaki Katayama, Katsunori Ishii, Naritsugu Kumai
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Publication number: 20090065347Abstract: Aromatic amines which have been obtained by reduction of aromatic nitro compounds are purified by mixing the crude amine obtained after phase separation with an aqueous, alkali metal hydroxide solution and subsequent distillation of this mixture over a distillation column. The distillation column has at least an upper and a lower rectifying part and a stripping part. The bottom product of the distillation column is partly to completely sluiced out and is partly evaporated in a main evaporator and at least one downstream re-evaporator and partly recycled back into the column.Type: ApplicationFiled: August 15, 2008Publication date: March 12, 2009Inventors: Knut Sommer, Franz-Ulrich Gehlen, Peter Lehner, Andre Dux, Benie Marotz
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Publication number: 20080230368Abstract: A method and a plant are disclosed for purifying lactams, particularly lactams obtained by cyclizing hydrolysis of aminonitrile. The purification of ?-caprolactam obtained by cyclizing hydrolysis of aminocapronitrile is described which includes eliminating the ammonia from the reaction medium of the hydrolysis, then recovering the lactam from said medium in purified form. The recovery is carried out by performing at least a distillation of the lactam in the presence of a base producing optionally a fronts fraction comprising compounds more volatile than the lactam, a fraction comprising the lactam to be recovered to the degree of desired purity and a distillation tails comprising the lactam and compounds less volatile than the lactam. The distillation tails are treated by various processes such as evaporation in thin layers to recover the major part of the caprolactam and recycling the latter in the purification process.Type: ApplicationFiled: May 29, 2008Publication date: September 25, 2008Applicant: RHODIA POLYAMIDE INTERMEDIATESInventors: Daniel Amoros, Philippe Leconte, Pierre Coqueret
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Patent number: 7384518Abstract: A method and a plant are disclosed for purifying lactams, particularly lactams obtained by cyclizing hydrolysis of aminonitrile. The purification of ?-caprolactam obtained by cyclizing hydrolysis of aminocapronitrile is described which includes eliminating the ammonia from the reaction medium of the hydrolysis, then recovering the lactam from said medium in purified form. The recovery is carried out by performing at least a distillation of the lactam in the presence of a base producing optionally a fronts fraction comprising compounds more volatile than the lactam, a fraction comprising the lactam to be recovered to the degree of desired purity and a distillation tails comprising the lactam and compounds less volatile than the lactam. The distillation tails are treated by various processes such as evaporation in thin layers to recover the major part of the caprolactam and recycling the latter in the purification process.Type: GrantFiled: May 28, 2001Date of Patent: June 10, 2008Assignee: Rhodia Polyamide IntermediatesInventors: Daniel Amoros, Philippe Leconte, Pierre Coqueret
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Patent number: 7309403Abstract: The invention relates to a method of avoiding corrosion in the separation of methylamine from a product stream (10) which is obtained in the preparation of methylamines by gas-phase reaction of methanol and ammonia and includes monomethylamine, dimethylamine, trimethylamine, ammonia and methanol as components, where ammonia is separated off by pure distillation in a first column (1), the remaining components of the product stream obtained as bottoms (12) are fed to a second column (2). Trimethylamine (14) is separated off in the second column (2) by extractive distillation with introduction of water. The further of the product stream obtained as bottoms (15) from the second column (2) are fed to a third column (3), in which monomethylamine and dimethylamine are separated off at the top. The monomethylamine and dimethylamine are separated by distillation in a fourth column (4). To avoid corrosion alkali metal hydroxide is added to the second or third column (3).Type: GrantFiled: September 24, 2004Date of Patent: December 18, 2007Assignee: BASF AktiengesellschaftInventors: Werner Reutemann, Theodor Weber, Karl-Heinz Ross, Manfred Julius
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Patent number: 7230126Abstract: The present invention provides a method capable of suppressing a decrease in optical purity due to the exposure to heat during distillation of an optically active epoxide to permit an optically active epoxide of high quality to be simply obtained on an industrial scale. In the method, an optically active epoxide is distilled in the presence of a base to suppress a decrease in optical purity.Type: GrantFiled: May 10, 2002Date of Patent: June 12, 2007Assignee: Kaneka CorporationInventors: Tadashi Moroshima, Yasuyoshi Ueda
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Patent number: 7105078Abstract: A process for preparing a salt-free aqueous hydroxylamine solution by reacting an aqueous solution of a hydroxylammonium salt with a base to give a mixture and separating from said mixture by distillation a salt-free aqueous hydroxylamine solution, involving using as a base an aqueous solution of a mixture of NaOH and KOH in a molar ratio Na+:K+ in the range from 70:30 to 95:5 and with a total concentration of Na+ and K+ in the range from 0.1 to 10 m/m % based on the total amount of the mixture.Type: GrantFiled: July 2, 2002Date of Patent: September 12, 2006Assignee: BASF AktiengesellschaftInventors: Karl-Heinz Wostbrock, Eckhard Ströfer, Markus Weber, Steffen Kerth
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Patent number: 7074434Abstract: Process for the separation of a mixture comprising at least one hydrofluoroalkane and hydrogen fluoride, according to which a hydrofluoroalkane/hydrogen fluoride mixture is reacted with at least one chlorinated or chlorofluorinated precursor of the hydrofluoroalkane. Process for the preparation of a hydrofluoroalkane comprising such a separation, in combination with a catalytic reaction stage. Azeotropic compositions.Type: GrantFiled: October 29, 2002Date of Patent: July 11, 2006Assignee: Solvay (Societe Anonyme)Inventors: Alain Lambert, Vincent Wilmet
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Publication number: 20040149563Abstract: A process for preparing a salt-free aqueous hydroxylamine solution by reacting an aqueous solution of a hydroxylammonium salt with a base to give a mixture and separating from said mixture by distillation a salt-free aqueous hydroxylamine solution, comprises using as a base an aqueous solution of a mixture of NaOH and KOH in a molar ratio Na+:K+ in the range from 70:30 to 95:5 and with a total concentration of Na+ and K+ in the range from 0.1 to 10 m/m % based on the total amount of the mixture.Type: ApplicationFiled: December 30, 2003Publication date: August 5, 2004Inventors: Karl-Heinz Wostbrock, Eckhard Strofer, Markus Weber, Steffen Kerth
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Publication number: 20040104107Abstract: The invention provides a hydrofluoric acid wastewater treatment method that achieves efficient recovery of hydrofluoric acid from hydrofluoric acid wastewater and also achieves sufficient reduction in the hydrofluoric acid concentration of the dehydrofluorinated water after treatment.Type: ApplicationFiled: November 26, 2003Publication date: June 3, 2004Applicants: SASAKURA ENGINEERING CO., LTD., SHARP KABUSHIKI KAISHAInventors: Junji Mizutani, Mitsuo Maeda, Tamito Mukaida, Yasushi Nishimura, Yutaka Shiomi, Koji Harada, Yoshio Tanimoto, Toshiaki Muratani
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Patent number: 6695928Abstract: A method for the production of (meth)acrylic acid and/or a (meth)acrylic ester is provided. This method for the production of (meth)acrylic acid and/or a (meth)acrylic ester includes washing the device constructed for the production thereof with a basic solution and subsequently rinsing them with a solvent for the purpose of removing solid substances such as polymer and precipitate which occur during the production of (meth)acrylic acid and/or a (meth)acrylic ester.Type: GrantFiled: March 1, 2000Date of Patent: February 24, 2004Assignee: Nippon Shokubai Co., Ltd.Inventors: Sei Nakahara, Takeshi Nishimura, Masatoshi Ueoka
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Publication number: 20040026228Abstract: A process for cleaning apparatus in which (meth)acrylic acid-containing organic solvents have been treated and/or generated and contain fouling and/or polymer and residues of organic solvent, in which the apparatus contents are subjected to a steam distillation in the apparatus.Type: ApplicationFiled: May 29, 2003Publication date: February 12, 2004Applicant: BASF AktiengesellschaftInventors: Volker Diehl, Ulrich Jager, Jurgen Schroder, Joachim Thiel
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Patent number: 6685802Abstract: This invention relates to a continuous process and an apparatus (1) for removing dissolved and undissolved solids and/or high boiling point liquid contaminants from a mixture of miscible liquids (9). A recycle liquor stream (6) is fed at high velocity through a heat exchanger having a single flow path (12) and the heat added by the heat exchanger is sufficient to vaporize the feed stream (2) when the recycle liquor and feed stream are mixed upon delivery to the separation vessel (3).Type: GrantFiled: July 2, 2001Date of Patent: February 3, 2004Inventor: Craig Nazzer
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Patent number: 6632331Abstract: Aldehyde compounds contained in polycyclic diols as impurities are effectively removed by distilling the polycyclic diols in the presence of an alkali metal compound and/or a alkaline earth compound. The distilled polycyclic diols are useful as a diol component of a polymer such as polycarbonate with less yellowing.Type: GrantFiled: July 26, 2001Date of Patent: October 14, 2003Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Shu Yoshida, Satoshi Nagai, Takashi Konishi, Makoto Sasaki
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Publication number: 20030127315Abstract: A tert-C4-C8-alkyl (meth)acrylate is prepared by reacting (meth)acrylic acid with an olefin of the formula 1Type: ApplicationFiled: January 27, 2003Publication date: July 10, 2003Inventors: Ruprecht Kroker, Gerhard Nestler, Werner Schmitt, Winfried Schumm
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Patent number: 6387224Abstract: A process for the separation by distillation of a mixture of 1,4-butanediol and at least one 4-hydroxybutyraldehyde, its cyclic hemiacetal and its cyclic full acetals with at least one further alcohol by carrying out the distillation in the presence of an alkaline compound. The mixture to be separated preferably contains a cyclic full acetal of 4-hydroxybutyraldehyde with a further alcohol which has a lower boiling point than butanediol and also the further alcohol in free form. The process is particularly suitable for the separation by distillation of mixtures formed in the hydrogenation of maleic acid derivatives.Type: GrantFiled: August 29, 2000Date of Patent: May 14, 2002Assignee: BASF AktiengesellschaftInventors: Rolf Pinkos, Rolf Fischer, Shelue Liang
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Publication number: 20020033324Abstract: Aldehyde compounds contained in polycyclic diols as impurities are effectively removed by distilling the polycyclic diols in the presence of an alkali metal compound and/or a alkaline earth compound. The distilled polycyclic diols are useful as a diol component of a polymer such as polycarbonate with less yellowing.Type: ApplicationFiled: July 26, 2001Publication date: March 21, 2002Inventors: Shu Yoshida, Satoshi Nagai, Takashi Konishi, Makoto Sasaki
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Patent number: 6299737Abstract: A process for recovering glycols from used glycol-containing technical fluids, especially from used antifreeze comprises adding to the used glycol-containing technical fluids an organic solvent which forms with the glycol to be separated off an azeotropic mixture which has a lower boiling point than the glycol itself and distilling off this azeotropic mixture.Type: GrantFiled: April 11, 1995Date of Patent: October 9, 2001Assignee: BASF AktiengesellschaftInventors: Jürgen Mohr, Wolf-Dieter Balzer
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Patent number: 6117277Abstract: The invention relates to a process for the purification of C.sub.3 -C.sub.10 -alcohols by distillation, by distilling the alcohols at 150 to 200.degree. C. in the presence of 10 to 1000 ppm of alkali metal hydroxide.Type: GrantFiled: August 22, 1997Date of Patent: September 12, 2000Assignee: Celanese Chemicals Europe GmbHInventors: Wolfgang Zgorzelski, Peter Lappe, Kurt Schalapski, Wilhelm Gick
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Patent number: 6093855Abstract: The divinyl ethers of diethylene glycol or triethylene glycol are separated from the monovinyl ether of the corresponding oligoethylene glycol by distillation, a metal hydroxide being added to the vinyl ether mixture.Type: GrantFiled: September 23, 1998Date of Patent: July 25, 2000Assignee: BASF AktiengesellschaftInventor: Rudolf Erich Lorenz
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Patent number: 5961788Abstract: A process for removing tetrahydroazepine from aminocapronitrile or hexamethylenediamine by sequential distillation in which the overhead from the second distillation is combined with a fresh, incoming mixture of tetrahydroazepine and aminocapronitrile or hexamethylenediamine.Type: GrantFiled: October 9, 1998Date of Patent: October 5, 1999Assignee: E. I. du Pont de Nemours and CompanyInventor: John Joseph Ostermaier
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Patent number: 5910234Abstract: This invention relates to a process for working up the alcohol-containing wastewater which is obtained in the hydrolysis of silanes of the general formula IR.sup.1.sub.a SiCl.sub.b (OR.sup.2).sub.4-a-b (I),whereR.sup.1 are hydrogen atoms or identical or different monovalent, unsubstituted or halogen-substituted, SiC-bonded C.sub.1 -C.sub.18 -hydrocarbon radicals,R.sup.2 are identical or different monovalent C.sub.1 -C.sub.10 -hydrocarbon radicals,a is 0, 1, 2 or 3, on average from 0.3 to 1.9, andb is 0, 1, 2, 3 or 4, on average from 0.0 to 3.0,with the proviso that the sum a+b is on average at most 3.5, for the preparation of silicone resins, wherein, in the first step, the wastewater is made alkaline by addition of alkali and, in the second step, the alcohol is removed from the resulting alkaline solution or suspension by injection of steam.Type: GrantFiled: July 25, 1997Date of Patent: June 8, 1999Assignee: Wacker-Chemie GmbHInventors: Konrad Mautner, Erwin Schuhbeck
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Patent number: 5902458Abstract: A steam stripping substance, which is obtained by steam distillation of sesame oil under reduced pressure and contains sesamin analogues substantially, is mixed with water, a water-soluble solvent or their mixture serving as solvent. Sesamin analogues are caused to precipitate in this mixed system in the presence of more than one equivalent of an alkali with respect to the acid value of the steam stripping substance. The precipitated sesamin analogues are then separated from the mixed system.Type: GrantFiled: April 21, 1997Date of Patent: May 11, 1999Assignee: Takemoto Yushi Kabushiki KaishaInventors: Masato Sugiura, Masanori Inayoshi, Shigeo Sakurai
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Patent number: 5788818Abstract: A process for the purification of raw acetone deriving from processes for the production of phenol acetone, impurity mainly due to cumene, water, aldehydes and methanol, the steps of:feeding the stream of raw acetone coming from the primary fractionation of a plant for the production of phenol and acetone to a first distillation column to which a solution of sodium hydroxide at 2% is also fed;sending the stream at the head of the first column, containing of acetone, water and cumene to a second column to which the extractive solvent triethyleneglycol is also fed;recovering substantially anhydrous acetone from the head of the second column;feeding the bottom product of the second column, containing triethyleneglycol, water, cumene and acetone to a third distillation column in which an azeotropic mixture of water and cumene is recovered from the head and anhydrous triethyleneglycol from the bottom;sending the azeotropic mixture of water and cumene to a decanter in which a water phase is separated, containing acType: GrantFiled: September 16, 1996Date of Patent: August 4, 1998Assignee: Enichem S.p.A.Inventors: Lorenzo Lorenzoni, Salvatore Simula, Giuseppe Messina, Riccardo Mansani
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Patent number: 5728272Abstract: In a process for the separation by rectification of unsaturated carboxylic acids from solvents in which the acids were absorbed after the synthesis reaction, the rectification is briefly interrupted and the rectification column is flushed with a basic solution. The interruption is carried out at regular time intervals. The basic solution used is an aqueous solution of alkali metal and/or alkaline earth metal hydroxide, preferably NaOH, KOH, Ca(OH).sub.2 or their anhydrous oxides; alkaline polar organic solvents as amines or amides can be used, too.Type: GrantFiled: August 13, 1996Date of Patent: March 17, 1998Assignee: BASF AktiengesellschaftInventors: Ulrich Hammon, Volker Schliephake, Wolfgang Pies, Ulrich Rauh
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Patent number: 5700358Abstract: Caprolactam is recovered from oligomers and/or polymers of caprolactam by cleavage of oligomers and/or polymers of caprolactam and subsequent working up by distillation of the caprolactam obtained in the cleavage, by a process including(a) cleaving oligomers and/or polymers of caprolactam to obtain an aqueous reaction mixture which contains caprolactam,(b) removing water from the reaction mixture obtained under (a) to obtain a residue,(c) distilling the residue obtained under (b) in an acidic medium and(d) then distilling the distillate in an alkaline medium to obtain caprolactam, or(c') distilling the residue obtained under (b) in an alkaline medium and(d') then distilling the distillate in an acidic medium to obtain caprolactam.Type: GrantFiled: March 1, 1995Date of Patent: December 23, 1997Assignee: BASF AktiengesellschaftInventors: Hugo Fuchs, Josef Ritz, Gerald Neubauer
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Patent number: 5667644Abstract: A method for producing a dimerized aldehyde, which comprises subjecting a feed aldehyde to a condensation reaction and a dehydration reaction in the presence of a basic catalyst, wherein the feed aldehyde is the one having one or two hydrogen atoms at the .alpha.-position, an organic feed stream containing the feed aldehyde is supplied to a reactive distillation column, and the condensation reaction and the dehydration reaction are carried out simultaneously in the reactive distillation column.Type: GrantFiled: February 9, 1996Date of Patent: September 16, 1997Assignee: Mitsubishi Chemical CorporationInventors: Tomoyuki Mori, Kouichi Fujita, Yuuji Kajita, Masaki Takai
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Patent number: 5616217Abstract: In the manufacture of MTBE from TBA and methanol, acidic by-products formed during the etherification reaction are removed by fractionating the etherification reaction product in a first MTBE distillation column to provide a first lower boiling distillation fraction comprising isobutylene, MTBE, methanol and acidic by-products and a first higher boiling distillation fraction comprising methanol, TBA and water, fractionating the first higher boiling distillation fraction in a recycle distillation column to provide a lower boiling TBA recycle fraction and a higher boiling water fraction, recycling the higher boiling water fraction to the MTBE distillation column at a charge point above the charge point for the etherification reaction product, and adding aqueous sodium hydroxide to the recycled higher boiling water fraction in an amount sufficient to neutralize the acidic by-products charged to the MTBE distillation column.Type: GrantFiled: August 17, 1995Date of Patent: April 1, 1997Assignee: Texaco Chemical Inc.Inventor: Mark E. Taylor
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Patent number: 5591311Abstract: A process for purifying impure 2,6-diisopropylphenol (DIP) mixtures having lower and higher boiling phenolic impurities is described. The process involves washing the mixture with aqueous alkali metal hydroxide solution in an inert atmosphere and separating the aqueous and organic phases, washing the resulting organic phase with water, and then subjecting the water-washed organic phase to distillation in an inert environment to recover purified DIP. Since only one distillation is required rather than two, the development of impurities in the DIP caused by in situ oxidation reactions at elevated temperatures due to the inevitable presence of traces of air in commercial distillation facilities is reduced to acceptable levels.Type: GrantFiled: October 26, 1995Date of Patent: January 7, 1997Assignee: Albemarle CorporationInventor: Venkataraman Ramachandran
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Patent number: 5554796Abstract: A process for the purification of tertiary alkyl hydroperoxide containing contaminating quantities of primary and secondary alkyl hydroperoxides by contacting the impure hydroperoxide mixture with anhydrous carboxylic acid derivative such as maleic anhydride and subsequently reacting the resulting mixture with basic material such as aqueous caustic and recovering purified tertiary alkyl hydroperoxide.Type: GrantFiled: April 29, 1994Date of Patent: September 10, 1996Assignee: ARCO Chemical Technology, L.P.Inventors: Ahmad Soltani-Ahmadi, Robert N. Cochran
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Patent number: 5522971Abstract: Pure, substantially neutral, low-volatile organic compounds including reactive double bonds are advantageously isolated from a liquid feedstock which contains said compounds in combination with acidic reaction components or auxiliary materials by (i) adding to the feedstock, as neutralizing agents, finely powdered oxides, carbonates and/or hydroxides of the alkali metals and/or alkaline earth metals; (ii) adding, at the same time as the addition of the neutralizing agents or thereafter, a limited amount of water to the mixture of feedstock and neutralizing agents; (iii) mechanically mixing the liquid and solid mixture thus formed for at least a few minutes; (iv) distilling off water from the hot reaction mixture under reduced pressure; and (v) removal from the liquid product of the solid phase now present. Pure products which even without distillation exhibit low residual acid values in combination with low color values result.Type: GrantFiled: June 7, 1994Date of Patent: June 4, 1996Assignee: Henkel Kommanditgesellschaft auf AktienInventors: Wolfgang Ritter, Stefanie Ortanderl
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Patent number: 5516406Abstract: A method of purifying the oxidate product formed by the liquid phase oxidation of C.sub.4 -C.sub.8 paraffinic hydrocarbons comprises adding a strong acid catalyst to the oxidate product to catalyze the break down of Michael addition products of unsaturated carbonyls and carboxylic acids so that the carbonyls can be distilled off during the initial stages of purification.Type: GrantFiled: December 15, 1994Date of Patent: May 14, 1996Assignee: Hoechst Celanese CorporationInventors: Nicole G. Wallace, Kenneth A. Windhorst
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Patent number: 5500098Abstract: Volatile acids containing metal salt impurities, such as metal pickling solutions-are regenerated by a process in which the acid is subjected to sulfuric acid distillation. Resulting volatile acid vapor is condensed and recycled to the pickle tank, while the residual acid mixture is treated in an acid sorption unit, preferably of the acid retardation type. Acid sorbed in the acid sorption unit is periodically eluted with water and recycled, while metal impurities are rejected in a deacidified by-product solution.Type: GrantFiled: August 5, 1993Date of Patent: March 19, 1996Assignee: Eco-Tec LimitedInventors: Craig J. Brown, Michael A. Sheedy