Patents by Inventor T. Thomas Shih

T. Thomas Shih 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: 5689012
    Abstract: A continuous process for the preparation of polyoxyalkylene polyethers using DMC catalysts as the polyoxyalkylation catalyst employs continuous addition of alkylene oxide in conjunction with continuous addition of starter and catalyst to a continuous oxyalkylation reactor. Despite the continuous introduction of starter, the molecular weight distribution of the polyether product is quite narrow, as indicated by the exceptionally low polydispersity of the product. The presence of low molecular weight species during the majority of the polyoxyalkylation also substantially eliminates extremely high molecular weight fractions having molecular weights greater than 100,000 Da, again without appreciably broadening molecular weight distribution. By withdrawing intermediate molecular weight polyether product or diverting a portion of the end product to prepare a catalyst/starter mixture, rapid and sustained reaction rates can be achieved while employing low molecular weight starters.
    Type: Grant
    Filed: July 18, 1996
    Date of Patent: November 18, 1997
    Assignee: ARCO Chemical Technology, L.P.
    Inventors: Jose F. Pazos, T. Thomas Shih
  • Patent number: 5352807
    Abstract: The method for the separating close-boiling impurities from propylene oxide essentially free of high molecular weight poly (propylene oxide) which comprises contacting the impure propylene oxide with solid activated carbon adsorbent and separating propylene oxide reduced in impurities content from the adsorbent.
    Type: Grant
    Filed: November 4, 1993
    Date of Patent: October 4, 1994
    Assignee: ARCO Chemical Technology, L.P.
    Inventor: T. Thomas Shih
  • Patent number: 5288882
    Abstract: A method of recovering optically active epoxy alcohols from asymmetric epoxidation reaction mixture is provided whereby the epoxy alcohol may be obtained in high yield with minimal degradation of optical purity. The process is also suitable for the synthesis of useful organic sulfonate derivatives of chiral epoxy alcohols.
    Type: Grant
    Filed: December 21, 1992
    Date of Patent: February 22, 1994
    Assignee: Arco Chemical Technology, L.P.
    Inventors: T. Thomas Shih, Wilfred P.-S. Shum
  • Patent number: 5187287
    Abstract: The method for the separating close-boiling impurities from C.sub.2 -C.sub.4 l alkylene oxide which comprises contacting the impure alkylene oxide with solid activated carbon adsorbent and separating alkylene oxide reduced in impurities content from the adsorbent.
    Type: Grant
    Filed: February 20, 1992
    Date of Patent: February 16, 1993
    Assignee: Arco Chemical Technology, L.P.
    Inventor: T. Thomas Shih
  • Patent number: 5133839
    Abstract: The present invention provides an improved process for the separation of impurities from a lower alkylene oxide, such as propylene oxide, by a process wherein the impure propylene oxide is first fractionally distilled to separate higher and lower boiling impurities, then the partially purified alkylene oxide is subjected to extractive distillation to separate additional impurities, the purified propylene oxide being separated as an overhead fraction.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: July 28, 1992
    Assignee: Arco Chemical Technology, L.P.
    Inventor: T. Thomas Shih
  • Patent number: 5129996
    Abstract: A method is provided for the separation by extractive distillation of hydrocarbon impurities from lower alkylene oxides such as propylene oxide wherein a glycol having 2 to 5 carbon atoms is used as extractive solvent.
    Type: Grant
    Filed: April 8, 1991
    Date of Patent: July 14, 1992
    Assignee: Arco Chemical Technology, L.P.
    Inventor: T. Thomas Shih
  • Patent number: 5107002
    Abstract: The method for the separating methyl formate from lower alkylene oxide such as propylene oxide which comprises contacting the impure alkylene oxide with basic ion exchange resin and separating alkylene oxide reduced in methyl formate content.
    Type: Grant
    Filed: December 6, 1990
    Date of Patent: April 21, 1992
    Assignee: Arco Chemical Technology, L.P.
    Inventor: T. Thomas Shih
  • Patent number: 5006206
    Abstract: A method is provided for the separation by extractive distillation of hydrocarbon impurities from propylene oxide wherein t-butyl alcohol/water is used as extractive distillation solvent.
    Type: Grant
    Filed: March 12, 1990
    Date of Patent: April 9, 1991
    Assignee: Arco Chemical Technology, Inc.
    Inventors: T. Thomas Shih, William J. Sim
  • Patent number: 5000825
    Abstract: A method is provided for the separation by extractive distillation of oxygenated impurities from a monoepoxide while avoiding epoxide loss, wherein lower glycol is used as extractive solvent in amounts so as to provide only up to about 0.3 mol % solvent in the vapor in the extractive distillation zone.
    Type: Grant
    Filed: June 6, 1990
    Date of Patent: March 19, 1991
    Assignee: Arco Chemical Technology, Inc.
    Inventors: T. Thomas Shih, John C. Jubin, Jr.
  • Patent number: 4918204
    Abstract: Purification of tetrahydrofuran from the dehydrocyclization of 1,4-butanediol in the presence of an organic acid catalyst has been accomplished by the extractive distillation of crude tetrahydrofuran containing water using monopropylene glycol as an extractive solvent.
    Type: Grant
    Filed: January 30, 1989
    Date of Patent: April 17, 1990
    Assignee: Arco Chemical Technology, Inc.
    Inventors: T. Thomas Shih, Te Chang