Hydroxy Aromatic (e.g., Phenol) Patents (Class 203/65)
  • Patent number: 8337671
    Abstract: Process for distillatively purifying polymerizable compounds using a high-boiling, inert, thermally long-term-stable substance as a boiling oil, characterized in that the boiling oil is disposed in the bottom of a rectification column.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: December 25, 2012
    Assignee: Evonik Röhm GmbH
    Inventors: Dirk Broell, Hermann Siegert
  • Patent number: 8002953
    Abstract: An energy-efficient extractive distillation process for producing anhydrous ethanol from aqueous/ethanol feeds containing any range of ethanol employs an extractive distillation column (EDC) that operates under no or greatly reduced liquid reflux conditions. The EDC can be incorporated into an integrated process for producing anhydrous ethanol used for gasoline blending from fermentation broth. By using a high-boiling extractive distillation solvent, no solvent is entrained by the vapor phase to the EDC overhead stream, even under no liquid reflux conditions. The energy requirement and severity of the EDC can be further improved by limiting ethanol recovery in the EDC. In this partial ethanol recovery design, ethanol which remains in the aqueous stream from the EDC is recovered in a post-distillation column or the aqueous stream is recycled to a front-end pre-distillation column where the ethanol is readily recovered since the VLE curve for ethanol/water is extremely favorable for distillation.
    Type: Grant
    Filed: July 13, 2007
    Date of Patent: August 23, 2011
    Assignees: AMT International Inc., CPC Corporation, Taiwan
    Inventors: Fu-Ming Lee, Kuang-Yeu Wu, Lindsey Vuong, Fong-Cheng Su, Tzong-Bin Lin, Jyh-Haur Hwang, Hung-Chung Shen, Po-Sung Cheng, Tai-Ping Chang
  • Publication number: 20090173618
    Abstract: The invention relates to a method for generating a vacuum and for separating volatile compounds during esterification, transesterification and/or polycondensation reactions. One or several jets of steam comprising a spray condenser, which is arranged up or downstream, are connected to the suction side of a reactor which is to be evacuated and phenol or steam containing phenol is used as propellant steam at a pressure of 0.5 hPa to approximately 1.5 MPa and liquid phenol or a liquid containing phenol is used as a spraying agent.
    Type: Application
    Filed: February 27, 2006
    Publication date: July 9, 2009
    Inventor: Rudolf Kämpf
  • Publication number: 20090166176
    Abstract: Process for distillatively purifying polymerizable compounds using a high-boiling, inert, thermally long-term-stable substance as a boiling oil, characterized in that the boiling oil is disposed in the bottom of a rectification column.
    Type: Application
    Filed: March 14, 2007
    Publication date: July 2, 2009
    Applicant: EVONIK ROEHM GMBH
    Inventors: Dirk Broell, Hermann Siegert
  • Patent number: 7141641
    Abstract: A method and apparatus for continuously producing an alkyl aryl ether and a diaryl carbonate by reacting a dialkyl carbonate and an aromatic alcohol in presence of a transesterification catalyst.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: November 28, 2006
    Assignee: General Electric Company
    Inventors: Vutukuru Lakshmi Narasimha Murthy, Ignacio Fernandez Vic, Ganesh Kailasam, Alberto Nisoli
  • Patent number: 6475347
    Abstract: Disclosed herein are compounds of the structure wherein R1, R2, and R3 are organic radicals of C1 to C20, such that the combination of the three contain at least twelve carbon atoms and R3 is bound to the methylene carbon atom between X and the aromatic ring by at least one saturated carbon atom, allowing it to be easily separated from the polymerizable monomer by distillation; R1 and R2 have sufficient steric bulk to protect the phenol from reacting with an alkoxy group or halogen bound to silicon; and X is a neutral heteroatomic radical of oxygen, nitrogen, or phosphorus; and their use as inhibitors for the polymerization of (meth)acryloxysilanes.
    Type: Grant
    Filed: August 8, 2001
    Date of Patent: November 5, 2002
    Assignee: Crompton Corporation
    Inventors: Robert E. Sheridan, Kenneth W. Hartman
  • Publication number: 20020038047
    Abstract: The invention relates to a process to separate linear 5-formylvalerate compound from a crude mixture comprising 5-formylvalerate compound and 2-, 3- and/or 4-formylvalerate compound by vacuum distillation, wherein the distillation is performed in the presence of a phenolic compound with a boiling point which is at least 10° C. higher than the boiling point of the 5-formylvalerate at 0.1-100 kPa.
    Type: Application
    Filed: August 16, 2001
    Publication date: March 28, 2002
    Inventors: Onko J. Gelling, Peter C. Borman
  • Patent number: 6315868
    Abstract: A method of separating methanol and dimethyl carbonate in a distillation column through extractive distillation. The extractive distillation is conducted in the presence of an extractive distillation agent which modifies the azeotropic behavior of the dimethyl carbonate/methanol mixture. A vapor side stream is removed from the distillation column.
    Type: Grant
    Filed: April 26, 1999
    Date of Patent: November 13, 2001
    Assignee: General Electric Company
    Inventors: Alberto Nisoli, Stephan Mathijs Bouwens, Michael Francis Doherty, Michael Francis Malone
  • Patent number: 6159346
    Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as dialkylhydroxylamine and/or the use of a vessel made of a nickel alloy.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: December 12, 2000
    Assignee: Elf Atochem North America, Inc.
    Inventors: Richard M. Crooker, Maher Y. Elsheikh, Anthony D. Kelton, Morris P. Walker, Danny W. Wright
  • Patent number: 6024841
    Abstract: 2-Methyl-1-butanol and 3-methyl-1-butanol are difficult to separate from 1 pentanol by conventional distillation or rectification because of the proximity of their boiling points. 2-Methyl-1-butanol and 3-methyl-1-butanol can be easily separated from 1-pentanol by extractive distillation. Effective agents are 3-carene, propylene glycol phenyl ether and dimethylsulfoxide.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: February 15, 2000
    Inventor: Lloyd Berg
  • Patent number: 6017423
    Abstract: 3-Methyl-2-pentenal cannot be separated from n-butanol by conventioal rectification because of the proximity of their boiling points. 3-methyl-2-pentenal can be readily separated from n-butanol by extractive distillation. Effective agents are 1-methyl-2-pyrrolidinone, 1,4-butanediol and phenol.
    Type: Grant
    Filed: July 23, 1999
    Date of Patent: January 25, 2000
    Inventor: Lloyd Berg
  • Patent number: 5972172
    Abstract: 1,2,4-Trimethylbenzene is difficult to separate from 1,2,3-trimethylbenzene by conventional distillation or rectification because of the proximity of their boiling points. 1,2,4-trimethylbenzene can be readily separated from 1,2,3-trimethylbenzene by extractive distillation. Effective agents are 3-nitrotoluene, m-cresol and sulfolane.
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: October 26, 1999
    Inventor: Lloyd Berg
  • Patent number: 5968322
    Abstract: A process for preparing refined acrylic esters, the process including steps of distilling an acrylic ester containing stream in the presence of hydroquinone or substituted hydroquinone, at a concentration in the range of 200 to 5000 ppmw, wherein the distillation is carried out in the presence of 0.001 to 1.0 % v, on the vapor phase, of oxygen.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: October 19, 1999
    Inventors: Peter Arnoldy, Eric Kragtwijk, Antoon Paul Michael Kremers
  • Patent number: 5897750
    Abstract: Acetone cannot be separated from a mixture of isopropanol and water because of the closeness of their boiling points. Acetone can be easily separated from isopropanol and water by extractive distillation. Effective extractive agents are 1-nitropropane, 3-carene, dimethylsulfoxide and 3-pentanone.
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: April 27, 1999
    Inventor: Lloyd Berg
  • Patent number: 5879517
    Abstract: 2-Butanol cannot be sparated from t-amyl alcohol by distillation or rectification because of the closeness of their boiling points. 2-Butanol is readily separated from t-amyl alcohol by extractive distillation. Effective agents are butyl ether, benzyl acetate and 1,2,4-trimethyl benzene.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: March 9, 1999
    Inventor: Lloyd Berg
  • Patent number: 5876569
    Abstract: Methyl ethyl ketone cannot be separated from ethanol by distillation or rectification because of the closeness of their boiling points. Methyl ethyl ketone is readily separated from ethanol by extractive distillation. Effective agents are methyl benzoate, phenol, glycerol and nitroethane.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: March 2, 1999
    Inventor: Lloyd Berg
  • Patent number: 5873981
    Abstract: A is a process for removing water from an alkanesulfonic acid such as methanesulfonic acid or ethanesulfonic acid by mixing an azeotropic excess of a phenolic compound with water and the alkanesulfonic acid, then boiling off substantially all of the water, and leaving as a remnant substantially all the alkanesulfonic acid and some of the phenol. This process is particularly useful for recycling an alkanesulfonic acid for a reaction which requires the phenolic compound as one of the reagents. One such reaction is the alkanesulfonic acid catalyzed condensation reaction of a phenolic compound with an .alpha.haloketone to form a chlorinated intermediate of a dihydroxy-.alpha.-alkylstilbene such as 4,4'-dihydroxy-.alpha.-alkylstilbene (DHAMS).
    Type: Grant
    Filed: December 26, 1996
    Date of Patent: February 23, 1999
    Assignee: The Dow Chemical Company
    Inventors: Son T. Nguyen, Louis L. Walker, Katherine S. Clement
  • Patent number: 5863391
    Abstract: Acetaldehyde may be effectively removed from a contaminated methanol stream using a distillation method wherein a solvent stream containing a relatively heavy polar compound such as water or propylene glycol is utilized as an extractive distillation solvent. Following the separation of the polar compound from the bottoms stream obtained by extractive distillation, the purified methanol may be recycled for use as a reaction solvent in an olefin epoxidation process.
    Type: Grant
    Filed: August 15, 1997
    Date of Patent: January 26, 1999
    Assignee: ARCO Chemical Technology, L.P.
    Inventors: Michael A. Rueter, John C. Jubin, Jr.
  • Patent number: 5840160
    Abstract: 3-Carene is difficult to separate from limonene by conventional distillation or rectification because of the proximity of their boiling points. 3-Carene can be readily separated from limonene by extractive distillation. Effective agents are o-cresol, 2,6-dimethyl-4-heptanone and triethylene glycol.
    Type: Grant
    Filed: December 6, 1996
    Date of Patent: November 24, 1998
    Inventor: Lloyd Berg
  • Patent number: 5830325
    Abstract: The disclosure relates to separating 1,1,1-trifluoroethane (HFC-143a from fluorocarbon impurities by using extractive distillation with an extractive agent comprising an alcohol. Examples of suitable extractive agents comprise at least one member from the group of methanol, butanol, ethanol, propanol, their isomers and cyclic compounds thereof, among others.
    Type: Grant
    Filed: March 28, 1996
    Date of Patent: November 3, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Barry Asher Mahler, Ralph Newton Miller
  • Patent number: 5824195
    Abstract: A process for distilling a crude acrylic silane solution particularly containing impurities in a commercial scale for separating acrylic silane in the presence of a hindered phenol and/or amine as polymerization inhibitor, the process being improved by using simultaneously a dialkyldithiocarbamic acid copper and/or N-nitrosophenylhydroxylamine salt as synergistic polymerization inhibitor.
    Type: Grant
    Filed: June 26, 1996
    Date of Patent: October 20, 1998
    Assignee: Chisso Corporation
    Inventors: Yoichi Kimae, Katsuyoshi Tsuchiya, Takashi Matsuo, Kiyoto Fukuda
  • Patent number: 5800681
    Abstract: Ethanol, isopropanol and water cannot be separated from each other by distillation or rectification because of minimum azeotropes. They are readily separated by extractive distillation. Effective agents are: dimethylsulfoxide for ethanol, phenol for isopropanol.
    Type: Grant
    Filed: April 21, 1997
    Date of Patent: September 1, 1998
    Inventor: Lloyd Berg
  • Patent number: 5795447
    Abstract: 2-Butanol cannot be separated from isobutanol by distillation or rectification because of the closeness of their boiling points. 2-Butanol is readily separated from isobutanol by extractive distillation. Effective agents are propylene glycol propyl ether, 2-methoxyethanol and ethyl acetate.
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: August 18, 1998
    Inventor: Lloyd Berg
  • Patent number: 5789629
    Abstract: 3-Methyl-1-butanol is difficult to separate from 1-pentanol by conventional distillation or rectification because of the proximity of their boiling points. 2 Methyl-1-butanol can be easily separated from 1-pentanol by extractive distillation. Effective agents are phenol, anisole and methyl salicylate.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: August 4, 1998
    Inventor: Lloyd Berg
  • Patent number: 5779862
    Abstract: 2-Methyl-1-butanol and 3-methyl-1-butanol are difficult to separate from 1-pentanol by conventional distillation or rectification because of the proximity of their boiling points. 2-Methyl-1-butanol and 3-methyl-1-butanol can be easily separated from 1-pentanol by azeotropic distillation. Effective agents are toluene, methyl acetate and tetrahydrofuran.
    Type: Grant
    Filed: March 17, 1997
    Date of Patent: July 14, 1998
    Inventor: Lloyd Berg
  • Patent number: 5772853
    Abstract: 1-Propanol and t-amyl alcohol cannot be separated by distillation or rectification because of the closeness of their boiling points. 1-Propanol is readily separated from t-amyl alcohol by extractive distillation. Effective agents are dipentene, amyl acetate and 1,4-dioxane.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: June 30, 1998
    Inventor: Lloyd Berg
  • Patent number: 5723024
    Abstract: 2-Methyl-1-propanol is difficult to separate from 1-butanol by conventional distillation or rectification because of the proximity of their boiling points. 2-Methyl-1-propanol can be readily separated from 1-butanol by extractive distillation. Effective agents are ethyl benzene, amyl acetate and propoxypropanol.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: March 3, 1998
    Inventor: Lloyd Berg
  • Patent number: 5720857
    Abstract: 1,2,4-Trimethylbenzene is difficult to sepparate from 1,2,3-trimethylbenzene because of the proximity of their boiling points. They are readily separated by azeotropic distillation. Effective agents are 1-propanol, methyl formate and 1-nitropropane.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: February 24, 1998
    Inventor: Lloyd Berg
  • Patent number: 5709781
    Abstract: 1-Butanol is difficult to separate from 2-pentanol by conventional distillation or rectification because of the proximity of their boiling points. 1-Butanol can be easily separated from 2-pentanol by extractive distillation. Effective agents are anisole, ethyl nonanate and butyl ether.
    Type: Grant
    Filed: February 11, 1997
    Date of Patent: January 20, 1998
    Inventor: Lloyd Berg
  • Patent number: 5705038
    Abstract: Phellandrene is difficult to separate from limonene by conventional distillation or rectification because of the proximity of their boiling points. Phellandreneecan be readily separated from limonene by extractive distillation. Effective agents are o-cresol, tripropylene glycol and isophorone.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: January 6, 1998
    Inventor: Lloyd Berg
  • Patent number: 5693194
    Abstract: Butyraldehyde cannot be separated from ethanol by conventional distillation or rectification because they form a minimum boiling azeotrope. Butyraldehyde can be readily separated from ethanol by extractive distillation. Effective agents are 2-propanol, m-xylene and dimethylsulfoxide.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: December 2, 1997
    Inventor: Lloyd Berg
  • Patent number: 5659095
    Abstract: A polymerization inhibitor composition for inhibiting the polymerization of aromatic vinyl monomers at elevated temperatures comprising:(a) a benzofuroxan derivative of the formula ##STR1## wherein R is C.sub.1 -C.sub.4 alkyl or alkoxy; R.sup.1 is a nitro group; and m and n are each independently 0, 1, or 2; and(b) a solvent selected from the group consisting of toluene, xylene, ethylbenzene, vinyltoluene, divinylbenzene, alpha-methylstyrene, and a C.sub.12 -C.sub.18 hydrocarbon,and methods for inhibiting the polymerization of aromatic vinyl monomers at elevated temperatures using this composition.
    Type: Grant
    Filed: March 13, 1996
    Date of Patent: August 19, 1997
    Assignee: Uniroyal Chemical Company, Inc.
    Inventors: Howard Stephen Friedman, Gerald John Abruscato, John Matthew DeMassa, Anthony Vincent Gentile, Anthony Vincent Grossi
  • Patent number: 5648573
    Abstract: The polymerization of a vinyl aromatic monomer such as styrene is inhibited by the addition of a composition of a benzoquinone derivative and a hydroxylamine compound.
    Type: Grant
    Filed: June 12, 1995
    Date of Patent: July 15, 1997
    Assignee: BetzDearborn Inc.
    Inventors: Graciela B. Arhancet, Inge K. Henrici
  • Patent number: 5602294
    Abstract: o-Xylene cannot be separated from p-xylene and m-xylene by conventional distillation or rectification because of the proximity of their boiling points. o-Xylene can be readily separated from mixtures of p-xylene and m-xylene by extractive distillation. Effective agents are o-cresol, dichloroacetic acid, methyl salicylate and 1-tetradecanol.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: February 11, 1997
    Inventor: Lloyd Berg
  • Patent number: 5597455
    Abstract: 3-Carene and limonene cannot be separated from each other by rectification because of the closeness of their boiling points. They are readily separated by extractive distillation. Effective agents are: diethylene glycol phenyl ether, nonyl phenol, tripropylene glycol methyl ether, ethyl salicylate, 4-ethylphenol and 2-phenoxyethanol.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: January 28, 1997
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5582693
    Abstract: 3-Carene and limonene cannot be separated from each other by rectification because of the closeness of their boiling points. They are readily separated by azeotropic distillation. Effective agents are: cyclopentanol, 2-nitropropane, ethyl formate amyl acetate dimethyl carbonate, tetrahydrofuran, acetic acid and 2-amino-amethyl-1-propanol.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: December 10, 1996
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5580427
    Abstract: Butyraldehyde cannot be separated from ethanol by conventional distillation or rectification because they form a minimum boiling azeotrope. Butyraldehyde can be readily separated from ethanol by azeotropic distillation. Effective agents are ethyl formate, hexane and isopropyl ether.
    Type: Grant
    Filed: November 7, 1995
    Date of Patent: December 3, 1996
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5562863
    Abstract: Vinyl aromatic monomer polymerization methods utilizing a composition of 2,6-di-tert-butyl-4-methylphenol and a substituted benzoquinonediimide compound are disclosed. Preferably, the composition is employed in an amount of 1 part to 10,000 parts per million parts monomer during distillation of styrene.
    Type: Grant
    Filed: July 18, 1995
    Date of Patent: October 8, 1996
    Assignee: Betz Laboratories, Inc.
    Inventor: Graciela B. Arhancet
  • Patent number: 5470440
    Abstract: Vinyl aromatic monomer polymerization methods utilizing a composition of 2,6-di-tert-butyl-4-methylphenol and a substituted benzoquinonediimide compound are disclosed. Preferably, the composition is employed in an amount of 1 part to 10,000 parts per million parts monomer during distillation of styrene.
    Type: Grant
    Filed: April 19, 1994
    Date of Patent: November 28, 1995
    Assignee: Betz Laboratories, Inc.
    Inventor: Graciela B. Arhancet
  • Patent number: 5470443
    Abstract: Isopropanol is difficult to separate from 2-butanone by conventional distillation or rectification because of the proximity of their boiling points. Isopropanol can be readily separated from 2-butanone by extractive distillation. Effective agents are o-cresol, ethylene glycol and nitroethane.
    Type: Grant
    Filed: January 10, 1995
    Date of Patent: November 28, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5458741
    Abstract: Benzene is difficult to separate from cyclohexane or cyclohexene by conventional distillation or rectification because of the close proximity of their boiling points. Benzene can be readily separated from cyclohexane or cyclohexene by using extractive distillation. Effective agents are: for benzene from cyclohexane, methyl acetoacetate; for benzene from cyclohexene, ethyl acetoacetate.
    Type: Grant
    Filed: January 14, 1994
    Date of Patent: October 17, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5453166
    Abstract: Ethanol is impossible to separate from 2-butanone by conventional distillation or rectification because of the minimum boiling azeotrope between these two. Ethanol can be readily separated from 2-butanone by extractive distillation. Effective agents are dipromyl amine, phenol and dimethylsulfoxide.
    Type: Grant
    Filed: November 7, 1994
    Date of Patent: September 26, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5453167
    Abstract: p-Xylene cannot be separated from m-xylene by distillation or rectification because of the proximity of their boiling points. p-Xylene can be separated from m-xylene by means of extractive distillation. Effective agents are 3-ethylphenol and isopropyl palmitate. Effective agents for separating mixtures of p-xylene, m-xylene and o-xylene are 2-butoxyethyl acetate and 1,1,1-trichloroethane.
    Type: Grant
    Filed: April 7, 1995
    Date of Patent: September 26, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5445716
    Abstract: Ethanol is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by extractive distillation. Effective agents are dipentene, anisole and ethyl benzene.
    Type: Grant
    Filed: October 18, 1994
    Date of Patent: August 29, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5443697
    Abstract: Heptane is difficult to separate from 1-heptene by conventional distillation or rectification because of the proximity of their boiling points. Heptane can be readily separated from 1-heptene by extractive distillation. Effective agents are diacetone alcohol, ethyl butyrate and dimethylsulfoxide.
    Type: Grant
    Filed: May 19, 1994
    Date of Patent: August 22, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5441608
    Abstract: p-Xylene cannot be separated from m-xylene by distillation or rectification because of the proximity of their boiling points. p-Xylene can be separated from m-xylene by means of extractive distillation. Effective agents are 3-ethylphenol and 1,1,2-trichloroethane. Effective agents for separating mixtures of p-xylene, m-xylene and o-xylene are 2-butoxyethyl acetate and 1,1,1-trichloroethane.
    Type: Grant
    Filed: May 23, 1994
    Date of Patent: August 15, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5407540
    Abstract: 3-Methyl-2-butanol is difficult to separate from 1-butanol by conventional distillation or rectification because of the proximity of their boiling points. 3-Methyl-2-butanol can be readily separated from 1-butanol by extractive distillation. Effective agents are ethyl n-valerate, dimethylacetamide and dimethylsulfoxide.
    Type: Grant
    Filed: September 23, 1994
    Date of Patent: April 18, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5397441
    Abstract: Ethyl benzene is difficult to separate from o-xylene by conventional distillation or rectification because of the closeness of their boiling points. Ethyl benzene can be readily separated from o-xylene by extractive distillation. Effective agents are phenol, cresols, nitrotoluenes and cyclododecanol.
    Type: Grant
    Filed: January 14, 1994
    Date of Patent: March 14, 1995
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5358608
    Abstract: 1-Propanol is difficult to separate from 2-butanol by conventional distillation or rectification because of the proximity of their boiling points. 1-Propanol can be readily separated from 2-butanol by extractive distillation. Effective agents are isobutyl acetate, isobornyl methyl acetate and ethyl butyrate.
    Type: Grant
    Filed: January 18, 1994
    Date of Patent: October 25, 1994
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg
  • Patent number: 5348625
    Abstract: Ethanol is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by extractive distillation. Effective agents are methyl caproate, cyclopentane and isobutyl acetate.
    Type: Grant
    Filed: January 14, 1994
    Date of Patent: September 20, 1994
    Assignee: Lloyd Berg
    Inventor: Lloyd Berg