Patents by Inventor John Yaw Ofori

John Yaw Ofori has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6197991
    Abstract: A method and catalyst system for economically producing aromatic carbonates from aromatic hydroxy compounds. In one embodiment, the present invention provides a method of carbonylating aromatic hydroxy compounds by contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst system that includes a catalytic amount of an inorganic co-catalyst containing lead and a catalytic amount of an inorganic co-catalyst containing titanium. In various alternative embodiments, the carbonylation catalyst system can include an effective amount of a palladium source and an effective amount of a halide composition. Further alternative embodiments can include catalytic amounts of various inorganic co-catalyst combinations.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: March 6, 2001
    Assignee: General Electric Company
    Inventors: James Lawrence Spivack, Donald Wayne Whisenhunt, James Norman Cawse, Bruce Fletcher Johnson, Grigorii Lev Soloveichik, John Yaw Ofori, Eric James Pressman
  • Patent number: 6191060
    Abstract: A method for efficient reclamation of metal catalyst species from aqueous extract streams diaryl cabonate synthesis, comprising treating a metal-containing aqueous extract stream of a mixture from the production of diaryl carbonates with a precipitating agent effective to selective precipitate one or more metal catalyst species from the extract. Use of these methods substantially reduces both financial and environmental concerns for the preparation of diaryl carbonates.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: February 20, 2001
    Assignee: General Electric Company
    Inventor: John Yaw Ofori
  • Patent number: 6160154
    Abstract: A method and catalyst system for economically producing aromatic carbonates from aromatic hydroxy compounds. In one embodiment, the present invention provides a method of carbonylating aromatic hydroxy compounds by contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst system that includes a catalytic amount of an inorganic co-catalyst containing copper. In various alternative embodiments, the carbonylation catalyst system can include an effective amount of a palladium source and an effective amount of a halide composition. Further alternative embodiments can include catalytic amounts of various inorganic co-catalyst combinations.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: December 12, 2000
    Assignee: General Electric Company
    Inventors: James Lawrence Spivack, Donald Wayne Whisenhunt, Jr., James Norman Cawse, Bruce Fletcher Johnson, Marsha Mottel Grade, Grigorii Lev Soloveichik, John Yaw Ofori, Eric James Pressman
  • Patent number: 6143937
    Abstract: A method for efficiently recovering a hydroxyaromatic compound from aqueous extract streams of diaryl carbonate reaction mixtures, comprises contacting the aqueous extracts with a suitable solvent, preferably diphenyl carbonate or anisole. The aqueous stream may then be further recycled or reclaimed, and the hydroxyaromatic compound isolated from the solvent for disposal or further use.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: November 7, 2000
    Assignee: General Electric Company
    Inventor: John Yaw Ofori
  • Patent number: 6143914
    Abstract: A method and catalyst system for economically producing aromatic carbonates from aromatic hydroxy compounds. In one embodiment, the present invention provides a method of carbonylating aromatic hydroxy compounds by contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst system that includes a catalytic amount of a combination of inorganic co-catalysts containing manganese and nickel; manganese and iron; manganese and chromium; manganese and cerium; manganese and europium; manganese, cerium, and europium; manganese, iron, and europium; or manganese and thorium. In various alternative embodiments, the carbonylation catalyst system can include an effective amount of a palladium source and an effective amount of a halide composition. Further alternative embodiments can include catalytic amounts of various other inorganic co-catalyst combinations.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: November 7, 2000
    Assignee: General Electric Company
    Inventors: James Lawrence Spivack, Donald Wayne Whisenhunt, Jr., James Norman Cawse, Bruce Fletcher Johnson, Grigorii Lev Soloveichik, John Yaw Ofori, Eric James Pressman
  • Patent number: 6090737
    Abstract: A method for efficient removal of lead co-catalyst species from organic process streams arising from diaryl carbonate synthesis, by contacting the organic reaction mixtures with an aqueous acid, salt, or acid/salt solution, thereby extracting the treated mixture into an aqueous phase, or by treating the organic reaction mixtures with solid oxalic acid or oxalic acid salt, or an aqueous solution of oxalic acid or oxalic acid salt, thereby resulting in precipitation of the lead. The precipitated lead may then be calcined to provide a lead compound that is catalytically active in the carbonylation of phenol to yield diary carbonates. Use of these methods will substantially reduce both financial and environmental concerns for the preparation of diaryl carbonates.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: July 18, 2000
    Assignee: General Electric Company
    Inventor: John Yaw Ofori
  • Patent number: 5981788
    Abstract: Catalytic materials including divalent palladium compounds, divalent cobalt compounds and bromide sources such as tetraalkylammonium and hexaalkylguanidinium bromides are removed from organic carbonylation reaction mixtures comprising said materials in combination with diaryl carbonate and hydroxyaromatic compound. The removal steps include extraction with an aqueous complexing solution for palladium, extraction with an aqueous non-basic and preferably ionic extractant for cobalt, and extraction with water to remove bromide source. These steps may be combined into an integrated process. Further steps of recycle of the palladium by reduction to elemental palladium and conversion to a catalytically active species, and conversion of cobalt to a catalytically active species, may be included in the integrated process.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: November 9, 1999
    Assignee: General Electric Company
    Inventors: John Yaw Ofori, Sheldon Jay Shafer, Eric James Pressman, Ganesh Kailasam, Julia Lam Lee