Aromatic Patents (Class 203/69)
  • Patent number: 4117000
    Abstract: A process is described for improving the synthesis of 4-oxocapronitrile by adding an inert solvent to the atmospheric pressure distillation of the reaction mixture so that the temperature of said distillation is maintained below about 195.degree. C.
    Type: Grant
    Filed: August 24, 1977
    Date of Patent: September 26, 1978
    Assignee: Stamicarbon, B.V.
    Inventors: Theodorus Balg, Constant M. A. Cramers, Hendrikus J. G. Maessen
  • Patent number: 4070408
    Abstract: An improved aromatics extraction process is disclosed. Key feature of the present invention is use of the fractionator in the hydrodealkylation unit or other unit with a benzene fraction to fractionate not only hydrodealkylated benzene but also extracted benzene. The extracted benzene is used as "pseudo" reflux in the hydrodealkylation unit fractionator, thereby reducing the reflux requirement. The conventional re-run fractionator for clay treated benzene extract is eliminated, since polymerized olefins in this extract are removed as a bottoms fraction from the hydrodealkylation fractionator.
    Type: Grant
    Filed: July 6, 1976
    Date of Patent: January 24, 1978
    Assignee: UOP Inc.
    Inventor: Anthony G. Vickers
  • Patent number: 4057471
    Abstract: Ethylene glycol or 1,2-propylene glycol contained in mixtures with lower carboxylate esters of the glycol is recovered by azeotropic distillation of the mixtures with an azeotroping agent forming a minimum boiling azeotrope with the ethylene glycol or the 1,2-propylene glycol, the distillation being effected with reflux of azeotroping agent as well as controlled reflux of the glycol to the distillation zone.
    Type: Grant
    Filed: September 12, 1975
    Date of Patent: November 8, 1977
    Assignee: Halcon International, Inc.
    Inventor: Chun Fei Chueh
  • Patent number: 4046641
    Abstract: A process and apparatus for the regeneration of washing oil which has been spent to recover naphthalene and/or benzol from coke oven gas. The spent washing oil is stripped by steam in a bubble column arranged as an integral part of a single main column that includes first, second and third exchange column sections disposed in a superimposed relation one above the other to receive the stripped vapors from the bubble column. The first exchange column section is fed with a mixture of toluene, xylene and naphthalene as a reflux, the second exchange column section is fed with water as the reflux and the third exchange column section is fed with benzol as the reflux. The head product from the column is condensed and passed through a first-phase separator to obtain a substantially anhydrous benzol fraction and a water fraction. These fractions are separately used as a reflux for the second and third exchange column sections.
    Type: Grant
    Filed: March 12, 1975
    Date of Patent: September 6, 1977
    Assignee: Dr. C. Otto & Comp. G.m.b.H.
    Inventor: Hansjurgen Ullrich
  • Patent number: 4045294
    Abstract: Ethylene glycol or 1,2-propylene glycol contained in mixtures with lower carboxylate esters of the glycol is recovered by azeotropic distillation of the mixtures with an azeotroping agent which is a hydrocarbon which has a boiling point at atmospheric pressure above 190.degree. C but at most about 220.degree. C and is free from linear secondary and tertiary hydrogen atoms.
    Type: Grant
    Filed: September 12, 1975
    Date of Patent: August 30, 1977
    Assignee: Halcon International, Inc.
    Inventors: Mitchell Becker, Jon R. Valbert
  • Patent number: 4040913
    Abstract: A process for the recovery of methacrylic acid from an aqueous effluent obtained by the vapor phase condensation of formaldehyde and propionic acid, where the effluent further contains unreacted formaldehyde and unreacted propionic acid, and where the recovery steps include: extracting the effluent with an organic solvent capable of azeotroping with propionic acid to obtain an organic phase and an aqueous raffinate; distilling the organic phase to remove 50-100% of the unreacted propionic acid and leaving as bottoms remaining unreacted propionic acid and methacrylic acid; distilling the methacrylic/propionic acid bottoms to obtain remaining unreacted propionic acid overhead and pure methacrylic acid as bottoms; distilling the aqueous raffinate with an entrainer to obtain dilute aqueous formaldehyde overhead and about 50% aqueous formaldehyde as bottoms; and distilling the dilute aqueous formaldehyde taken overhead to concentrate it to about 35% aqueous concentration.
    Type: Grant
    Filed: September 2, 1975
    Date of Patent: August 9, 1977
    Assignee: Rohm and Haas Company
    Inventors: James S. Clovis, Jerome Dohling, Francis J. Nicastro
  • Patent number: 4033829
    Abstract: Styrene is inhibited against polymerization during the distillation thereof by incorporating therein, in an amount sufficient to inhibit polymerization thereof, the dinitrophenol solution recovered from styrene still residues or tars resulting from the distillation of styrene in the presence of dinitrophenol. The recovered dinitrophenol solution is a more effective polymerization inhibitor than dinitrophenol per se.
    Type: Grant
    Filed: December 15, 1975
    Date of Patent: July 5, 1977
    Assignee: Monsanto Company
    Inventors: Thomas D. Higgins, Jr., Raymond A. Newsom
  • Patent number: 4029552
    Abstract: A process is disclosed for obtaining a high purity perfluoro-n-heptane from an electrochemical fluorination product which comprises perfluoro-n-heptane, n-heptane, partially fluorinated heptanes, and water soluble acidic components such as hydrofluoric acid and is derived from the electrochemical fluorination of n-heptane.
    Type: Grant
    Filed: October 24, 1975
    Date of Patent: June 14, 1977
    Assignee: Phillips Petroleum Company
    Inventor: George B. Fozzard
  • Patent number: 4021311
    Abstract: Ethylene glycol or 1,2-propylene glycol contained in mixtures with lower carboxylate esters of the glycol is recovered by azeotropic distillation of the mixtures with 1,2,3-trimethyl benzene.
    Type: Grant
    Filed: September 12, 1975
    Date of Patent: May 3, 1977
    Assignee: Halcon International, Inc.
    Inventor: Mitchell Becker
  • Patent number: 4000044
    Abstract: Separation by distillation and formation of immiscible liquid phases of nearly equal densities which comprises distilling a mixture containing the same in the presence of an added liquid of substantially different density, preferentially soluble in a recycle to the distillation zone and having a volatility under conditions of distillation such that it will vaporize preferentially to a liquid desired to be retained in the distillation zone to be removed as bottoms therefrom, e.g., toluene added to produce gravity separation of a heavy water-rich phase and a light phase containing phenol, cyclohexanone and cyclohexylbenzene and the added toluene which is used as reflux to the drying column in the overall process in which cyclohexanone and phenol are produced from cyclohexylbenzene.
    Type: Grant
    Filed: July 9, 1974
    Date of Patent: December 28, 1976
    Assignee: Phillips Petroleum Company
    Inventor: Howard B. Irvin
  • Patent number: 3979432
    Abstract: An improved process for the production of aliphatic nitriles having two to six carbon atoms by the reaction of an aliphatic carboxylic acid with ammonia in the presence of a catalyst followed by effluent distillation. The improvement lies in the addition of a portion of the aliphatic carboxylic acid after the reactor but before distillation whereby ammonium carboxylate formed in the reaction and dissociated by distillation is reformed to the carboxylate thus preventing the escape of dissociated ammonia and whereby the aliphatic carboxylic acid portion is recycled to the reaction.
    Type: Grant
    Filed: October 6, 1975
    Date of Patent: September 7, 1976
    Assignee: Eastman Kodak Company
    Inventors: Hugh J. Hagemeyer, Jr., Jerry D. Holmes
  • Patent number: 3968153
    Abstract: A method for extraction of acrylic acid and/or methacrylic acid from a solution containing the same by treating the said solution with an organic solvent, which is characterized by using a mixture of methylethylketone and a xylene as the organic solvent. By such method, the extraction of acrylic acid and/or methacrylic acid is accomplished efficiently and economically.
    Type: Grant
    Filed: May 10, 1973
    Date of Patent: July 6, 1976
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Tetsuya Ohrui, Yasuhito Sakakibara, Yukinaga Aono, Michio Kato, Hiroshi Takao, Masami Ayano
  • Patent number: 3964980
    Abstract: The conventional process for the recovery of ethylene oxide produced by the silver catalyzed, vapor phase, partial oxidation of ethylene with molecular oxygen involves a sequence of steps including absorption in water of the ethylene oxide contained in the reaction effluent. The ethylene oxide-containing absorbate is then stripped and the vapor thus generated is subjected to reabsorption, also in water. This invention provides an improved stripper-reabsorption system and includes the steps of partial condensation of the stripper overhead and introduction of an additional absorbent stream into the readsorption step.
    Type: Grant
    Filed: March 24, 1975
    Date of Patent: June 22, 1976
    Assignee: Halcon International, Inc.
    Inventor: Brian I. Ozero
  • Patent number: 3959371
    Abstract: The present invention relates to the recovery of N,N-dimethylacetamide from a mixture containing N,N-dimethylacetamide and acetic acid. Potassium hydroxide is added to the mixture to neutralize the acetic acid and form potassium acetate having a low solubility in N,N-dimethylacetamide and a high affinity for water. The water concentration is adjusted to a desired range and a water non-solvent such as benzene is added to effect separation of an aqueous solution of potassium acetate from the dimethylacetamide as two distinct phases. The phases are then separated and the dimethylacetamide removed from the solvent phase by distillation.
    Type: Grant
    Filed: October 8, 1974
    Date of Patent: May 25, 1976
    Assignee: Custom Organics, Inc.
    Inventors: Gilbert Gavlin, Abid Hashim Bengali