Purification Or Recovery Patents (Class 564/497)
  • Patent number: 4570019
    Abstract: A process is provided which may be run continuously for producing polyethylene polyamines having improved color characteristics which comprises treating discolored polyethylene polyamines with polyethylene polyamine hydrochloride in the presence of water at elevated temperatures for the time necessary to reduce the color of said polyethylene polyamines and then flash evaporating the decolorized polyethylene polyamines from the treating mixture.
    Type: Grant
    Filed: February 8, 1984
    Date of Patent: February 11, 1986
    Assignee: Union Carbide Corporation
    Inventors: Charles A. Gibson, John W. Crandall
  • Patent number: 4532354
    Abstract: The present invention relates to a method for purifying N,N-dimethylaminopropylamine containing 1,3-diaminopropane as an impurity. Dimethylaminopropionitrile is formed by adding dimethylamine to acrylonitrile, and is then converted by subsequent hydrogenation and distillation into N,N-dimethylaminopropylamine. The impurity 1,3-diaminopropane is removed by adding a metal salt of a transition element which forms a stable complex with the 1,3-diaminopropane.
    Type: Grant
    Filed: May 19, 1982
    Date of Patent: July 30, 1985
    Assignee: Ruhrchemie Aktiengesellschaft
    Inventors: Boy Cornils, Ernst Wiebus, Norbert Breitkopf
  • Patent number: 4507475
    Abstract: A process for purifying crude polyether polyols which are prepared by anionic polymerization of alkylene oxides in the presence of basic catalysts. The polyols are mixed with water and ortho-phosphoric acid in certain quantity ratios, an adsorption agent is incorporated in the reaction mixture, the mixture is filtered and the water is removed from the polyether polyol by distillation.
    Type: Grant
    Filed: July 22, 1983
    Date of Patent: March 26, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Wolfgang Straehle, Raymond Denni, Matthias Marx
  • Patent number: 4409198
    Abstract: Copper(II) chloride is prepared from copper(II) oxychloride in a nonpolar solvent, preferably during oxychlorination. As the source of hydrogen chloride, the hydrochlorides of certain tertiary amines having 12-40 carbon atoms in total are utilized. The amine contains at most one N-methyl group and its dissociation constant K.sub.a of the equilibrium reactionNR.sub.3 H.sup..sym. +H.sub.2 O.revreaction.NR.sub.3 +H.sub.3 O.sup..sym.is 10.sup.-3.5 to 10.sup.-8.5. Preferred tertiary amines are a trialkylamine of 15-36 carbon atoms; an N-alkylazacycloalkane of the formula ##STR1## wherein R is alkyl of 6-15 carbon atoms, 5.ltoreq.n.ltoreq.8, ALK represents one or more alkyl substituents, and the N-alkylazacycloalkane contains at least 15 carbon atoms; or an N,N-dialkylaniline wherein each alkyl group independently contains 6-12 carbon atoms and the benzene ring is optionally substituted by one or more alkyl groups of 1-3 carbon atoms each.
    Type: Grant
    Filed: August 4, 1982
    Date of Patent: October 11, 1983
    Assignee: Chemische Werke Huls, AG
    Inventors: Alfred Coenen, Manfred Schroeder, Guenter Prominski
  • Patent number: 4409386
    Abstract: An acid extraction process for separating 3,4-dichloroaniline from 2,3-dichloroaniline and 2,5-dichloroaniline is disclosed. The process involves selectively forming 3,4-dichloroaniline hydrochloride, since it has a higher basicity than the other dichloroaniline isomers, in a multiple stage extraction unit. An aqueous solution of 3,4-dichloroaniline hydrochloride is removed from the multiple stage extraction unit and neutralized with a base to form an immiscible mixture of an aqueous salt solution and 3,4-dichloroaniline which are separated by decantation.
    Type: Grant
    Filed: August 6, 1982
    Date of Patent: October 11, 1983
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Tzu-Ching Chang
  • Patent number: 4407703
    Abstract: A mixture of isomers of an alkylamine, for example ethylamine is separated into its constituent components by a process in which the mixture is first distilled and at least one pure component separated from the mixture. The remainder of the mixture is then subjected to a multi-stage liquid-liquid extraction, preferably in five theoretical stages using water as extractant. For example, in the separation of mixtures of ethylamines, substantially all of the mono-ethylamine and a large proportion of the di-ethylamine is recovered in the distillation stage. The use of a multi-stage extraction (instead of the more usual single-stage extraction) to treat the remainder of the mixture leads to an enhanced yield of tri-ethylamine and lower consumption of energy and of extractant.
    Type: Grant
    Filed: February 18, 1982
    Date of Patent: October 4, 1983
    Assignee: Imperial Chemical Industries PLC
    Inventor: William Featherstone
  • Patent number: 4400539
    Abstract: There is described a continuous process for the manufacture of ethylenediamine from the products of the reaction of ethylene oxide and ammonia, provision of a continuous recycle stream of monoethanolamine to the products of the reaction of ethylene oxide and ammonia, the amination of such products of the reaction of ethylene oxide and ammonia combined with the monoethanolamine recycle in which the feed stream to the amination reaction zone contains at least 70 weight percent monoethanolamine as well as diethanolamine and triethanolamine, the moles of ammonia provided to the amination reaction exceeds the molar concentration of alcoholic hydroxyl groups present in the amination feed, and the feed to the amination reactor contains at least a 5% increase in the concentration of monoethanolamine over the concentration of monoethanolamine in the reaction product stream from the reaction of ethylene oxide and ammonia.
    Type: Grant
    Filed: September 30, 1981
    Date of Patent: August 23, 1983
    Assignee: Union Carbide Corporation
    Inventors: Charles A. Gibson, John R. Winters
  • Patent number: 4398041
    Abstract: A process for converting a C.sub.1 -C.sub.4 alcohol to a non-equilibrium controlled distribution of mono-, di- and trialkylamines is disclosed. A mixture of the alcohol and ammonia is reacted in a first conversion reactor containing a shape selective catalyst to yield a first product stream comprising the mono- and disubstituted alkylamines and substantially no trisubstituted alkylamine. A predetermined fraction of the first product stream is removed and the remainder of the stream is reacted in a second conversion reactor containing a catalyst which yields a second product stream comprising an equilibrium controlled distribution of the mono-, di- and trisubstituted alkylamine. The fraction of the first product stream and the second product stream are combined to yield an alkylamines stream comprising a non-equilibrium controlled alkylamines distribution.
    Type: Grant
    Filed: January 29, 1982
    Date of Patent: August 9, 1983
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Robert N. Cochran, Michel Deeba
  • Patent number: 4395311
    Abstract: Crude aminomethanols are converted to salt form by the addition of a strong acid and subsequently distilled under vacuum. The resulting purified aminomethanol is essentially free of unreacted aldehydes and other volatile impurities.
    Type: Grant
    Filed: November 30, 1981
    Date of Patent: July 26, 1983
    Assignee: The Dow Chemical Company
    Inventor: Charles J. McDonald
  • Patent number: 4381408
    Abstract: A method and apparatus are disclosed for extracting amine compounds from air samples without loss due to formation of nitrosamine artifacts. The apparatus includes a cartridge having a separation zone between a first port and a second port. The separation zone contains an air pervious packing of a granular, solid phase amine complexing agent. The method includes a first step of driving an air sample through the separation zone of the cartridge from the first port to the second port, and a second step of driving an eluent through the separation zone from the second port to the first port, or backflushing the cartridge. To extract amine compounds, the eluent is a solvent for the amine complexing agent in the separation zone of the cartridge. The method may contain the further step of determining the amine compound concentration of at least a portion of the eluate which passes from the separation zone following the second step of the method.
    Type: Grant
    Filed: December 1, 1980
    Date of Patent: April 26, 1983
    Assignee: Thermo Electron Corporation
    Inventors: David P. Rounbehler, John W. Reisch
  • Patent number: 4328366
    Abstract: This invention provides a process for recovery of sodium formate from an aqueous waste stream which is a byproduct mother liquor derived from a reaction system in which pentaerythritol is produced by the reaction of formaldehyde with acetaldehyde in the presence of sodium hydroxide catalyst.As one of its important features, the invention process involves contacting the mother liquor with a monoalkylamine solvent which is highly selective for extraction of organic materials to the exclusion of sodium formate.
    Type: Grant
    Filed: February 25, 1980
    Date of Patent: May 4, 1982
    Assignee: Virginia Chemicals Inc.
    Inventors: Charles E. Winslow, Jr., Leonard C. Ellis
  • Patent number: 4326082
    Abstract: Triethylamine and water are simultaneously removed from solutions in organic solvents, by liquid/liquid extraction with concentrated aqueous solutions of (C.sub.2 H.sub.5).sub.3 N.H.sub.3 PO.sub.4 which preferably contain free phosphoric acid as well. Upon heating of the resulting extract, the water and amine taken up are boiled off and the extractant regenerated. The method is of particular value in the preparation of aqueous coating compositions comprising reaction products of polyether epoxides and H.sub.3 PO.sub.4 in organic media. The reaction product is salified with triethylamine in excess, in the presence of added water. The organic solvent is boiled off, together with the excess amine and some of the water, to form an aqueous dispersion of the salified product and a distillate which can be processed by the method of the invention. The recovered solvent, water and amine may be recycled.
    Type: Grant
    Filed: April 7, 1980
    Date of Patent: April 20, 1982
    Assignee: The Dow Chemical Company
    Inventors: Patrick H. Martin, Stephen L. Michaels
  • Patent number: 4324917
    Abstract: An improved process for selectively preparing a predominantly noncyclic polyalkylene polyamine compound is disclosed wherein an alkyleneamine compound is contacted with an alkanolamine compound in the presence of a phosphorus-containing cation exchange resin at a temperature of from about 250.degree. C. to about 400.degree. C. under a pressure sufficient to maintain the mixture essentially in liquid phase and the polyalkylene polyamine is then recovered from the resultant reaction mixture. In a preferred embodiment ethylenediamine is contacted with monoethanolamine to produce a predominantly linear polyethylene polyamine product with very low yields of heterocyclic amine materials. The desired polyethylene polyamines produced can be directly recovered from the reaction products by known purification procedures.
    Type: Grant
    Filed: August 28, 1980
    Date of Patent: April 13, 1982
    Assignee: Texaco Inc.
    Inventor: Thomas T. McConnell
  • Patent number: 4310697
    Abstract: This invention relates to a process for the manufacture of dimethylethylamine comprising reacting gaseous ethanol with a gaseous mixture of hydrogen and dimethylamine in the presence of a hydrogenation/dehydrogenation catalyst comprising copper and chromic oxide alone or admixed with barium oxide, zinc oxide, magnesium oxide, or other oxides, at a temperature of about 180.degree. C. to 240.degree. C. and an absolute pressure of about 1 to 15 bars for a time sufficient to form dimethylethylamine, the molar ratio of dimethylamine/ethanol being about 0.2 to 0.6 and the molar ratio of hydrogen/ethanol being about 3 to 10.
    Type: Grant
    Filed: August 12, 1980
    Date of Patent: January 12, 1982
    Assignee: Produits Chimiques Ugine Kuhlmann
    Inventors: Bernard Cheminal, Paul Kiener, Aime Traversaz
  • Patent number: 4289908
    Abstract: This invention relates to an improvement in a process for preparing lower acyclic saturated amines by the gas phase hydrogenation of nitriles. To carry out the gas phase hydrogenation, the temperatures utilized in the reaction zone are from about 150.degree. to 350.degree. C., the pressure from about atmospheric to 500 psia, and the space velocity from about 750-20,000. Preferably, the conditions are controlled such that the components in the reaction zone are not exposed to a temperature greater than 380.degree. C. for a period of time in excess of 0.03 seconds.
    Type: Grant
    Filed: July 19, 1979
    Date of Patent: September 15, 1981
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Eckhart R. Becker, Randall J. Daughenbaugh, Barton Milligan
  • Patent number: 4283254
    Abstract: An improvement in the distillative refining of methylamines containing higher amine impurities wherein the higher amines accumulate in the distillation column, tending to cause flooding and product contamination. The improvement involves purging the column at the point the impurities concentrate, mixing the purge with water to form two phases, separating the phases and recycling the water phase for recovery of its methylamines content.
    Type: Grant
    Filed: April 3, 1980
    Date of Patent: August 11, 1981
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Douglas E. Binau, Emmett J. Speicher
  • Patent number: 4259309
    Abstract: An improvement in the process for obtaining gaseous hydrogen chloride by extracting dilute aqueous hydrochloric acid with amines wherein:(a) the aqueous hydrochloric acid is extracted with an amine or a mixture of an amine and an inert, water-immiscible solvent boiling at not less than 120.degree. C., using tertiary alkylamines which contain 14 to 36 carbon atoms in the nitrogen-bonded side chains, which side chains include at most one nitrogen-bonded methyl group and at least one nitrogen-bonded aliphatic radical containing at least 6 carbon atoms, the acid constant K.sub.a of the amine being less than 10.sup.-3 ;(b) an inert, water-immiscible solvent boiling at not less than 120.degree. C.
    Type: Grant
    Filed: August 8, 1979
    Date of Patent: March 31, 1981
    Assignee: Chemische Werke Huls AG
    Inventors: Alfred Coenen, Kurt Kosswig, Ferdinand von Praun