Phosphoric Or Sulfuric Acid Patents (Class 203/35)
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Patent number: 10253009Abstract: Methods and processes for the production of valuable organic products and alcohols from biomass using a single-step dehydration extraction process having numerous advantages over prior production methods are described.Type: GrantFiled: August 13, 2015Date of Patent: April 9, 2019Assignee: SHELL OIL COMPANYInventors: Juben Nemchand Chheda, Jean Paul Andre Marie Joseph Ghislain Lange
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Patent number: 8758573Abstract: The present application concerns a process for the removal of hydrocarbons from an aqueous stream, which process may include conducting a phenol-containing water stream into a separation column, separating the phenol-containing water in the column using heat to form an overhead portion and a bottoms portion, and collecting the overhead portion as well as the bottoms portion. Further, the process may include adding an eluent to an aqueous stream, thereby forming an aqueous mixture, subsequently conducting the aqueous mixture into a separation vessel, wherein it is allowed to settle into two phases, which form a hydrocarbon stream and a phenol-containing water stream, subsequently collecting the hydrocarbon stream, and conducting the phenol-containing water stream to the separation column for further separation.Type: GrantFiled: December 22, 2008Date of Patent: June 24, 2014Assignee: Borealis Technology OyInventors: Henrik Andtsjo, Maarit Aarni-Sirvio
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Publication number: 20130168227Abstract: Furfural is produced in one step at both high yield and high conversion from a feedstock comprising solid biomass and/or insoluble polysaccharide, in a high boiling, water-miscible solvent containing a soluble acid catalyst, and water. Furfural product and water can be distilled off, leaving non-volatile solvent behind. Because furfural contact with the acidic medium is minimized, degradation is kept to a minimum. The feedstock does not have to be pretreated. Because the biomass undergoes near complete dissolution, the residual material is flowable and easier to handle than residual solids reported from other processes. Further, certain by-products (e.g., humins, lignins) solubilized in the reaction solvent can be precipitated by addition of water or aqueous solution and then removed from the reaction mixture.Type: ApplicationFiled: December 28, 2012Publication date: July 4, 2013Applicant: E I DU PONT DE NEMOURS AND COMPANYInventor: E I DU PONT DE NEMOURS AND COMPANY
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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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Publication number: 20100314239Abstract: The present invention relates to a process for purifying methacrylic acid, wherein the reaction mixture obtained by a reaction of methacrylamide with water is cooled by mixing with an aqueous medium and then passed into a phase separator. The present invention further describes a system for performing the process according to the invention.Type: ApplicationFiled: January 13, 2009Publication date: December 16, 2010Applicant: EVONIK ROEHM GMBHInventors: Udo Gropp, Stefanie Sohnemann, Guido Protzmann, Thomas Mertz
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Publication number: 20090223804Abstract: A process for co-manufacture of acrylonitrile and hydrogen cyanide comprises combining a stream comprising hydrogen cyanide and an acrylonitrile reactor product stream, to produce a combined product stream, having a ratio of acrylonitrile to hydrogen cyanide of about 9 to 1 or less, which can be varied; and treating the combined product stream in a recovery/purification system of acrylonitrile process wherein pH is controlled by addition of an acid to prevent HCN polymerization. The ratio of acrylonitrile to hydrogen cyanide is generally between 2 to 1 and 9 to 1. The stream comprising hydrogen cyanide is advantageously a hydrogen cyanide product stream from a hydrogen cyanide synthesis reactor.Type: ApplicationFiled: March 5, 2008Publication date: September 10, 2009Inventors: Brent E. Basham, Richard T. Stimek
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Publication number: 20090223805Abstract: Processes comprising: (a) reacting dimethylamine and ethylene oxide to form a product mixture comprising N,N-dimethylethanolamine and N,N-dimethylaminoethoxyethanol; (b) distilling the product mixture to obtain a bottom fraction comprising N,N-dimethylaminoethoxyethanol; and (c) distilling the bottom fraction to separate at least a portion of the N,N-dimethylaminoethoxyethanol from the bottom fraction; and apparatus for carrying out said processes.Type: ApplicationFiled: March 20, 2007Publication date: September 10, 2009Applicant: BASF AktiengesellschaftInventors: Frank-Friedrich Pape, Alfred Krause, Johann-Peter Melder, Bernd Stein, Joachim-Thierry Anders, Frank Haese
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Patent number: 7501047Abstract: The disclosure relates to a process for purifying crude caprolactam. The process involves converting a first mixture of 6-amino capronitrile and water to a second mixture of caprolactam ammonia, water, high boilers and low boilers using a catalyst. The ammonia is removed from the second mixture to obtain a third mixture. Water is removed from the third mixture to give crude caprolactam, high boiler and low boilers. Purified caprolactam is then obtained by a series of distillation steps.Type: GrantFiled: November 11, 2003Date of Patent: March 10, 2009Assignee: BASF AktiengesellschaftInventors: Hermann Luyken, Andreas Ansmann, Christoph Benisch, Peter Baβler, Rolf-Hartmuth Fischer, Stefan Maixner, Johann-Peter Melder
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Patent number: 7481878Abstract: A method for the preparation of activated clays and cement additives from contaminated drill cuttings is provided. The substrate can be mixed with a mineral acid in a first reactor. The acidified substrate is then mixed with alkaline earth in a second reactor. The reactions are exothermic and provide heat to vaporize the contaminants, reaction products, and water. Recoverable constituents in the vapor can be condensed in a vapor collection system. The treated substrate can be heated and/or further reacted with acid, resulting in the formation of activated clays. For production of cement additives, the treated substrate can then be heated in a kiln and combined with cement clinker material for the preparation of cement and/or concrete.Type: GrantFiled: August 12, 2005Date of Patent: January 27, 2009Assignee: Racional Energy & Environment Co.Inventor: Ramon Perez-Cordova
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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: 7175819Abstract: Spent, acidic solutions comprising cupric chloride and hyrdrochloric acid from the copper etching process are regenerated by a process in which the acid is subjected to distillation with sulfuric acid. In one embodiment, the process comprises (a) providing a spent etchant comprising at least about 10% by weight chloride and at least about 5% dissolved copper; (b) adding at least about 2 moles of sulfuric acid per mole of dissolved copper to the spent etching solution, thereby converting copper chloride into hydrochloric acid and precipitated copper sulfate; (c) distilling the mixture from step (b) to vaporize at least a portion of the hydrochloric acid; (d) condensing at least a portion of the vaporized hydrochloric acid; (e) separating at least a portion of the precipitated copper sulfate from the residual liquid, wherein said residual liquid comprises sulfuric acid; and (f) reusing at least a portion of the residual liquid as a sulfuric acid source in step (b).Type: GrantFiled: March 4, 2005Date of Patent: February 13, 2007Assignee: Phibro-Tech, Inc.Inventors: Gang Zhao, H. Wayne Richardson
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Patent number: 7074304Abstract: A process for purifying alicyclic alcohols by distillation, wherein the alicyclic alcohols are distilled in the presence of from 1 to 550 ppm of acidic compounds.Type: GrantFiled: December 13, 2002Date of Patent: July 11, 2006Assignee: Celanese Chemicals Europe GmbHInventors: Wolfgang Dukat, Peter Lappe, Klaus Schmid, Horst Scholz, Edgar Storm
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Patent number: 6825379Abstract: The present invention relates to a method for recovering and producing C4-C6 dicarboxylates from an alkaline waste solution generated in a caprolactam preparation process, in which the alkaline waste solution is treated with sulfuric acid to separate into an aqueous phase and an organic phase, allowing valuable substances contained in the organic phase to be firstly oxidized and converted into dicarboxylic acids. The dicarboxylic acids then undergo concentration, esterification and distillation processes, so as to obtain desirable C4-C6 dicarboxylates with high purity. This therefore provides an efficient and improved method for effectively recovering most valuable substances from the alkaline waste solution, so that economic benefits in recovery are greatly raised.Type: GrantFiled: January 14, 2002Date of Patent: November 30, 2004Assignee: Chemaxz International CorporationInventors: Sien-Chun Chou, Edward K. S. Wang, Chung Ho Wu, Yaw Jong Liu, Ping Chiang
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Patent number: 6638398Abstract: A method including evaporating aqueous solutions containing ammonia, adding an acid to the evaporated vapor flow to form an ammonium salt, and condensing the vapor flow to form a liquid containing the salt. By this method the ammonia formed into a salt is not present as an inert gas layer which would impede condensation on the condenser surfaces.Type: GrantFiled: May 21, 2002Date of Patent: October 28, 2003Assignee: Hadwaco Ltd OyInventors: Leif Ramm-Schmidt, Matti Laajaniemi, Peter Koistinen
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Publication number: 20030045750Abstract: The present invention relates to a method for recovering and producing C4-C6 dicarboxylates from an alkaline waste solution generated in a caprolactam preparation process, in which the alkaline waste solution is treated with sulfuric acid to separate into an aqueous phase and an organic phase, allowing valuable substances contained in the organic phase to be firstly oxidized and converted into dicarboxylic acids. The dicarboxylic acids then undergo concentration, esterification and distillation processes, so as to obtain desirable C4-C6 dicarboxylates with high purity. This therefore provides an efficient and improved method for effectively recovering most valuable substances from the alkaline waste solution, so that economic benefits in recovery are greatly raised.Type: ApplicationFiled: January 14, 2002Publication date: March 6, 2003Applicant: CHEMAX INTERNATIONAL CORPORATIONInventors: Sien-Chun Chou, Edward K.S. Wang, Chung Ho Wu, Yaw Jong Liu, Ping Chiang
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Patent number: 6488818Abstract: A process for removing impurities from 3-(2′-acetoxyethyl)dihydro-2(3H)furanone (I), where the 3-(2′-acetoxyethyl)dihydro-2(3H)furanone containing the undesirable impurities is initially prepared in a manner known per se by acetylation of 3-(2′-hydroxyethyl)dihydro-2(3H)furanone and the resulting product is subsequently subjected to a distillation or rectification, includes carrying out the distillation or rectification in a plurality of steps, where high-boiling impurities are removed in a first step, the product which is drawn off via the top is subsequently subjected to at least one further step in which low-boilers and intermediate boilers are drawn off via the top and the desired pure I is obtained as bottom product.Type: GrantFiled: September 8, 1999Date of Patent: December 3, 2002Assignee: BASF AktiengesellschaftInventors: Volker Maywald, Horst Hartmann, Norbert Götz, Gernot Reissenweber, Hartmann König
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Patent number: 6464838Abstract: A process for the recovery of compounds present in a mixture containing residues of heavy products is provided. The process includes conducting a reaction and distillation to obtain the compounds and residues and macerating the residues before they can set to mass. The residues can then be destroyed. The process is particularly suitable for the treatment of the residues obtained in the preparation of phenol from cumene.Type: GrantFiled: July 12, 1999Date of Patent: October 15, 2002Assignee: Rhodia ChimieInventors: Jean-Jacques Charrin, Francoise Igersheim, Antonio Queiroz
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Patent number: 6375808Abstract: A process for refining difluoromethane by removing hydrogen fluoride, which is contained in difluoromethane difficult to remove. The process involves distilling a mixture of difluoromethane with hydrogen fluoride where the mixture is in contact with sulfuric acid. The hydrogen fluoride remains in the liquid phase and the difluoromethane goes into the vapor phase.Type: GrantFiled: April 26, 1999Date of Patent: April 23, 2002Assignee: Daikin Industries Ltd.Inventors: Takehide Tsuda, Takashi Shibanuma, Yasufu Yamada
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Patent number: 6274726Abstract: The invention is based on the discovery that hyperbaric, hydrostatic pressure reversibly alters the partitioning of biomolecules between certain adsorbed and solvated phases relative to partitioning at ambient pressure. The new methods and devices disclosed herein make use of this discovery for highly selective and efficient, low salt isolation and purification of nucleic acids from a broad range of sample types, including forensic samples, blood and other body fluids, and cultured cells. In one embodiment, the invention features a pressure-modulation apparatus. The apparatus includes an electrode array system having at least two (i.e., two, three, four, or more) electrodes; and a conduit interconnecting the electrodes. The conduit contains an electrically conductive fluid in contact with a phase positioned in a pressure chamber. The phase can be, for example, a binding medium or stationary phase.Type: GrantFiled: January 30, 1998Date of Patent: August 14, 2001Assignee: BBI Bioseq, Inc.Inventors: James A. Laugharn, Jr., Robert A. Hess, Feng Tao
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Patent number: 6111096Abstract: The invention is based on the discovery that hyperbaric, hydrostatic pressure reversibly alters the partitioning of nucleic acids between certain adsorbed and solvated phases relative to partitioning at ambient pressure. The new methods and devices disclosed herein make use of this discovery for highly selective and efficient, low salt isolation and purification of nucleic acids from a broad range of sample types, including forensic samples, blood and other body fluids, and cultured cells.Type: GrantFiled: October 31, 1997Date of Patent: August 29, 2000Assignee: BBI BioSeq, Inc.Inventors: James A. Laugharn, Jr., Robert A. Hess, Feng Tao
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Patent number: 5989394Abstract: A process for purification treatment of an impure liquid, such as a contaminated condensate, obtained when producing paper or paper pulp. The liquid is introduced intro a stripper device at an admission point (C) and the stripper device is also supplied with an acidifier preferably at a point (D) that is located above the admission point (C) and malodorous gases are driven off from the stripper device.Type: GrantFiled: July 9, 1997Date of Patent: November 23, 1999Assignee: Kvaerner Pulping ABInventors: Mikael Johansson, Krister Strom, Anders Wernqvist
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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: 5693190Abstract: A method for the recovery of glycols from used antifreeze compositions by distillation entails the used antifreeze composition being treated before and/or during its distillation with an effective amount of sulfamic acid.Type: GrantFiled: December 4, 1995Date of Patent: December 2, 1997Assignee: BASF AktiengesellschaftInventor: Kurt Schneider
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Patent number: 5632866Abstract: A method of recycling and purifying cleaning chemicals used in the production of semiconductor circuits and containing hydrofluoric acid and or hydrochloric acid. Recycling of such chemicals is accomplished using separation and reconstitution steps Hydrofluoric acid and hydrochloric acid cannot be distilled directly from a chemical solution as they form azeotropes with water. A low vapor pressure substance such as sulfuric acid or phosphoric acid is used to break the azeotrope while increasing the purity of the recovered chemicals and decreasing disposal problems. The method is useable at the point of use of the chemicals.Type: GrantFiled: January 12, 1994Date of Patent: May 27, 1997Assignee: FSI International, Inc.Inventor: Donald C. Grant
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Patent number: 5620567Abstract: A process for the removal of aldehydes and acetals from industrially prepared acetic acid, wherein the contaminated acetic acid is reacted in the presence of a Bronstedt acid and 0.05 to 1% by weight of water and, if required, of 3 to 10 equivalents, calculated on aldehyde and acetal, of a high boiling polyhydric alcohol, and isolating the purified acetic acid by fractional distillation.Type: GrantFiled: July 29, 1994Date of Patent: April 15, 1997Assignee: Hoechst AktiengesellschaftInventors: Andreas Seidel, Alfred Hauser, Peter Prinz
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Patent number: 5589037Abstract: Tetranitromethane and other polynitrated methanes can be effectively removed from otherwise substantially organic-free nitric acid streams through the addition of substantially organic-free concentrated sulfuric acid and by, optionally, performing secondary operations such as sparging the mixed acid stream with a gas such as nitric oxide or with an oil.Type: GrantFiled: October 24, 1995Date of Patent: December 31, 1996Assignee: General Electric CompanyInventors: Thomas L. Guggenheim, Sharon M. Fukuyama, Gregory L. Warner
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Patent number: 5587056Abstract: At least a fraction of at least one branched, saturated aliphatic diacid having 6 carbon atoms, for example 2-methylglutaric acid and/or 2-ethylsuccinic acid and/or dimethylsuccinic acid, is separated from admixtures thereof with adipic acid, by at least partially converting such at least one aliphatic diacid into the corresponding anhydride thereof, and removing the corresponding anhydride or the adipic acid from the medium of conversion/anhydridization, for example by contemporaneous or subsequent distillation, or by crystallization.Type: GrantFiled: June 14, 1995Date of Patent: December 24, 1996Assignee: Rhone-Poulenc ChimieInventors: Philippe Denis, Carl Patois, Robert Perron
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Patent number: 5536376Abstract: A method for producing 2-chloropyridine and 2,6-dichloropyridine by the steps of mixing vaporized chlorine and vaporized water to obtain dilute chlorine; introducing the dilute chlorine and vaporized pyridine into a reactor; and reacting the vaporized pyridine with the dilute chlorine in a gas phase under ultraviolet rays irradiation. By the method, 2-chloropyridine and 2,6-dichloropyridine can be produced in high yields. The present invention is also directed to a method for separating 2,6-dichloropyridine from a mixture containing 2,6-dichloropyridine, 2-chloropyridine and pyridine by the step of carrying out distillation of the mixture containing 2,6-dichloropyridine, 2-chloropyridine and pyridine in the presence of water while adding sulfuric acid to a distillation column. Highly purified 2,6-dichloropyridine can be separated by the method.Type: GrantFiled: December 28, 1993Date of Patent: July 16, 1996Assignee: Sumitomo Seika Chemicals Co., Ltd.Inventors: Shigenobu Yamaguchi, Johji Ogasahara, Hiroyuki Hata, Ryoichi Tokura, Hiromoto Shigeta
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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
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Patent number: 5458740Abstract: A process for the purification of caprolactam from crude caprolactam by distilling the crude caprolactam in the presence of an anorganic or organic acid.Type: GrantFiled: March 4, 1994Date of Patent: October 17, 1995Assignee: BASF CorporationInventors: Thomas P. Losier, Donald R. Johnson, Hugo Fuchs, Gerald Neubauer, Josef Ritz
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Patent number: 5240566Abstract: A process for separating acetone, dichloromethane and trifluoroacetic acid from a mixture of acetone, dichloromethane, and a trifluoroacetic acid/acetone azeotropeby (1) fractionally distilling the mixture of acetone, dichloromethane, and the trifluoroacetic acid/acetone azeotrope;(2) fractionally distilling the mixture of the trifluoroacetic acid/acetone azeotrope and free acetone;(3) adding at least about 16 parts of water to the trifluoroacetic acid/acetone azeotrope per 100 parts by volume of the trifluoroacetic acid/acetone azeotrope;(4) fractionally distilling the mixture of free acetone and the water/trifluoroacetic acid azeotrope;(5) adding at least about 10 parts of sulfuric acid to the water/trifluoroacetic acid azeotrope per 100 parts by volume of the water/trifluoroacetic acid azeotrope;(6) fractionally distilling the mixture of trifluoroacetic acid and the water/sulfuric acid complex.Type: GrantFiled: December 7, 1992Date of Patent: August 31, 1993Assignee: The Goodyear Tire & Rubber CompanyInventors: Bruce R. Hahn, Thomas R. Maier, Surendra K. Chawla
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Patent number: 5236557Abstract: Aqueous solutions which are contaminated by hydrogen sulfide, hydrogen cyanide, and ammonia are brought to a pH of about 3 or less after their formation and treated with an inert gas in a stripping column to remove the sulfide and cyanide. The pH of the solution is then increased to about 10 or more and the solution is again treated with an inert gas in a second stripping column to remove the ammonia.Type: GrantFiled: December 18, 1991Date of Patent: August 17, 1993Assignee: Hoechst AktiengesellschaftInventors: Thomas Muller, Rolf-Dieter Fischer, Ulrich Gerhardus, Norbert Leder, Klaus Poloszyk, Peter Schneller, Wolfgang Brunke
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Patent number: 5227028Abstract: A process of treating a ketoxime or aldoxime-containing amide mixture resulting from a Beckmann rearrangement of the corresponding ketoxime or aldoxime. The process involves hydrolysis of the mixture to remove the remaining ketoxime or aldoxime which are converted to the corresponding ketone or aldehyde and then separated off from the mixture. Any amino acid resulting from the hydrolysis can be reconverted to the corresponding amide by raising the temperature of the mixture.Type: GrantFiled: July 3, 1991Date of Patent: July 13, 1993Assignee: DSM N.V.Inventors: Hubertus J. M. Bosman, Paul C. Van Geem, Petrus J. H. Thomissen
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Patent number: 5160413Abstract: Micro-distillation apparatus is provided for analyzing acidic anions in which the acidic anion sample is placed in a lower elongated member in water containing an acidifying material, upon heating the acidic anion leaves the lower member as a gas, passing through a permeable membrane into an upper elongated member containing a material which converts the acidic anion to a salt and the salt is recovered for analysis. The micro-distillation apparatus is sized so that a number of samples can be heated in a small heating member, such as a hot block heater.Type: GrantFiled: August 16, 1990Date of Patent: November 3, 1992Assignee: Conoco Inc.Inventor: Joe D. Allison
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Patent number: 5158651Abstract: A process for removing inorganic compounds from glycol recovery still bottoms resulting from the manufacture of poly(ethylene terephthalate), the novel process using a small amount of phosphoric acid to precipitate the antimony and then removing the titanium dioxide and antimony compound by a centrifuge. The novel process for removing the inorganic compounds from the recovery polyester bottoms includes the steps of distilling ethylene glycol from the spent glycol until the remaining bottoms have a solids concentration from about 15% to about 45%; adding phosphoric acid to the bottoms to form an antimony compound and removing the antimony and titanium precipitates from the bottoms by a centrifuge.Type: GrantFiled: June 11, 1990Date of Patent: October 27, 1992Assignee: Hoechst Celanese CorporationInventor: Marvin L. Doerr
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Patent number: 5094720Abstract: A method is disclosed for enhancing the purification of citral by fractional distillation by inhibiting the formation of isocitrals from isomerization of citral during the distillation process. The method involves reducing the pH of a mixture containing citral to inhibit the formation of isocitrals from citral upon heating, such as in distillation. Lowering the pH below 7 reduces formation of isocitrals, but a pH of about 4 to 5 is especially preferred. Most preferably, this pH adjustment is accomplished by addition of an acid with a pKa between about 4 and 5.Type: GrantFiled: October 18, 1990Date of Patent: March 10, 1992Assignee: Union Camp CorporationInventor: David E. Sasser
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Patent number: 5064507Abstract: High purity phenol is obtained from cleavage of cumene hydroperoxide by treating the crude phenol product stream in a first treatment zone with an amine, a coarse distillation to obtain an overhead stream comprising phenol, alpha-methyl styrene, cumene, and impurities, and steam distillation of the overhead stream in combination with addition of an amine to the steam distillation column for a second amine treatment step.Type: GrantFiled: September 27, 1990Date of Patent: November 12, 1991Assignee: Allied-Signal Inc.Inventors: Michael S. O'Donnell, Lamberto Crescentini
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Patent number: 5004829Abstract: (CF.sub.3 SO.sub.2).sub.2 O is formed by reaction of CF.sub.3 SO.sub.3 H with P.sub.2 O.sub.5 and taken out of the reaction system by distillation, but the residue of the distillation contains a considerable amount of unreacted CF.sub.3 SO.sub.3 H. From the residue unreacted by adding water or a phosphoric acid solution, preferably the latter, to the residue to obtain a fluidic mixture containing an adequate amount of water and subjecting the mixture to distillation, preferably under reduced pressure at temperatures ranging from 180.degree. to 280.degree. C. It is possible to form additional CF.sub.3 SO.sub.3 H during the recovery process by adding a metal salt of CF.sub.3 SO.sub.3 H to the aformentioned mixture since the metal salt is decomposed by phosphoric acid contained in the mixture.Type: GrantFiled: April 9, 1990Date of Patent: April 2, 1991Assignee: Central Glass Company, LimitedInventors: Minoru Aramaki, Takashi Suenaga, Hiroaki Sakaguchi, Takanori Hamana
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Patent number: 4966276Abstract: An integrated continuous processes for concentrating "weak" nitric acid and concurrently reconcentrating the spent dehydrating agent used to break the nitric acid azeotrope to obtain "strong" nitric acid, the processes involving direct coupling of the nitric acid concentration with the reconcentration of the spent dehydrating agent so that less energy input is required. The major proportion of the feed "weak" nitric acid is vaporized before being fed countercurrently into a column to contact a large volume of the dehydrating agent, this vaporization being one of the two major sources of energy input, the second being through the reboiler at the bottom of the column. Energy input is balanced by energy rejection through condensation of strong nitric acid vapor and water vapor.Type: GrantFiled: April 17, 1989Date of Patent: October 30, 1990Inventor: Alfred A. Guenkel
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Patent number: 4956157Abstract: A process for obtaining available elements from seawater is described, which process includes two separation steps. The first separation step involved adjusting the pH of seawater to a low pH by adding a strong acid having sulphate ion, adding a strongly alkaline agent thereto in amount sufficient to provide a high pH and separating the precipitate formed thereby from the filtrate. The second separation step involves concentrating the filtrate, cooling the concentrated filtrate and separating a precipitate thereby formed. Each precipitate and each filtrate obtained in these steps has characteristic components and can be utilized for many purposes, for example, for food additives, as a solvent for paint, as combustion aids, or as alkaline agents for neutralization etc.Type: GrantFiled: May 30, 1989Date of Patent: September 11, 1990Inventor: Atsushi Nasu
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Patent number: 4946029Abstract: Carboxylic esters obtained by reacting olefinically unsaturated compounds with carbon monoxide and alcohols and containing aldehydes, acetals and/or unsaturated compounds are purified by(a) treating the carboxylic ester which contains an aldehyde, acetal or unsaturated compound in a first stage at from 20.degree. to 200.degree. C. with a strongly acidic agent and(b) hydrogenating the mixture thus treated in a second stage at from 50.degree. to 200.degree. C. under a pressure of from 1 to 50 bar in the presence of one or more metals of subgroup VIII of the periodic table and(c) removing low and high boilers from the hydrogenated mixture obtained in stage b by distillation and obtaining a pure carboxylic ester.Type: GrantFiled: February 24, 1989Date of Patent: August 7, 1990Assignee: BASF AktiengesellschaftInventors: Gerhard Frank, Hubert Lendle, Wilfried Seyfert, Peter Stops
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Patent number: 4944848Abstract: A process for the purification of 1,1-diphenylethane with good fragrance quality. The product is produced by first subjecting the distillation residue from ethylbenzene production to distillation, then treating the distillate with sulfuric acid, separating the sulfuric acid phase, washing the oil phase with an alkali metal hydroxide solution and water, and subjecting the oil phase thus obtained to a second distillation.Type: GrantFiled: September 21, 1989Date of Patent: July 31, 1990Assignee: Huels AktiengesellschaftInventor: Manfred Kaufhold
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Patent number: 4939294Abstract: In a process for the production of methyl acetate from methanol and glacial acetic acid involving countercurrently flowing acetic acid and methanol through a single reactive distillation column having an extractive distillation section and a methyl acetate/acetic acid rectification section to obtain methyl acetate in the presence of an acidic catalyst, the improvement which comprises producing ultra high purity methyl acetate by the additional step of introducing acetic anhydride and a salt-free acid catalyst into the reactive distillation column between the extractive distillation section and the methyl acetate/acetic acid rectification section.Type: GrantFiled: May 22, 1989Date of Patent: July 3, 1990Assignee: Eastman Kodak CompanyInventors: Victor H. Agreda, Ronnie D. Lilly
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Patent number: 4915794Abstract: This invention relates to a process for producing an olefin product having an enhanced alpha olefin content from an olefin feedstock containing internal olefins or a mixture of internal and alpha olefins which includes:(a) contacting the feedstock with an anthracene and a double-bond isomerization catalyst at a temperature ranging from about 150.degree. to about 275.degree. C. to form an olefin adduct with anthracene,(b) separating the adduct from the product of step (a),(c) heating the separated adduct at a temperature ranging from about 250.degree. to about 400.degree. C. to produce anthracene and an olefin product enhanced in alpha olefin content over the alpha olefin content of the feedstock, and(d) separating anthracene from the product of step (c) to produce the product enhanced in alpha olefin.Linear olefins are a preferred feedstock.Type: GrantFiled: October 27, 1988Date of Patent: April 10, 1990Assignee: Shell Oil CompanyInventors: Lynn H. Slaugh, Howard L. Fong
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Patent number: 4851085Abstract: A process which comprises treating butyrolactone in at least 95% purity with an acid to convert and remove color forming impurities for product stabilization.Type: GrantFiled: July 11, 1988Date of Patent: July 25, 1989Assignee: GAF CorporationInventor: Waldo De Thomas
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Patent number: 4830712Abstract: A process is described for recovering polyester-grade ethylene glycol from crude ethylene glycol containing at least one component which has a normal boiling point below that of ethylene glycol, and which can form a UV absorber in the presence of ethylene glycol which comprises supplying to an ethylene glycol distillation system, preferably comprising a fractional distillation zone having an upper portion, a lower portion and an intermediate portion a crude ethylene glycol stream at a determined pH of less than about 7.Type: GrantFiled: September 29, 1987Date of Patent: May 16, 1989Assignee: Union Carbide CorporationInventors: John W. Crandall, Bernard C. Ream
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Patent number: 4737243Abstract: A method of removing color from crude triethylenetetramine (TETA) is disclosed. In the preferred procedure, acid treated clay or acidic form zeolite are mixed with the TETA at elevated temperatures. After several hours exposure, the TETA is distilled to obtain a decolored product. The decoloration can be a continuous or batch process. The distillation is performed in the presence or absence of the catalyst.Type: GrantFiled: December 16, 1985Date of Patent: April 12, 1988Assignee: The Dow Chemical CompanyInventors: Robert J. Siml, Clara S. Dannhaus, Enrique G. Ramirez
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Patent number: 4720328Abstract: A method for removing impurities from caprolactam is disclosed. The method comprises the sequential steps of treating the impure caprolactam with phosphorus pentoxide so that the impurities react therewith to form high boiling species and then distilling the so treated impure lactam to recover substantially pure caprolactam as overhead, with the impurities remaining as bottoms.Type: GrantFiled: September 2, 1983Date of Patent: January 19, 1988Assignee: Akzona IncorporatedInventors: Tom F. Corbin, Jack A. Dellinger, Kenneth B. Wagener