Patents by Inventor Kent Edward Mitchell

Kent Edward Mitchell 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: 7432339
    Abstract: A method for producing polyphenylene sulfide (PPS) polymer, including polymerizing reactants in a reaction mixture in a vessel to form PPS polymer in the vessel, measuring values of operating variables of the vessel and/or PPS process, and determining the amount of quench fluid to add to the vessel based on the values of the operating variables. The technique may rely on the vapor liquid equilibrium (VLE) of the mixture to calculate the concentration of water existing in the reactor prior to quench, and accounts for the effectiveness of the upstream dehydration process and in the amount of water produced during the polymerization. The technique is a striking improvement over the trial-and-error estimation of the amount of quench water based on human operating experience, and avoids direct measurements of the existing water concentration in the reactor. The result is improved control of PPS particle size and other properties.
    Type: Grant
    Filed: December 24, 2007
    Date of Patent: October 7, 2008
    Assignee: Chevron Phillips Chemical Company LP
    Inventor: Kent Edward Mitchell
  • Patent number: 7312300
    Abstract: A method for producing polyphenylene sulfide (PPS) polymer, including polymerizing reactants in a reaction mixture in a vessel to form PPS polymer in the vessel, measuring values of operating variables of the vessel and/or PPS process, and determining the amount of quench fluid to add to the vessel based on the values of the operating variables. The technique may rely on the vapor liquid equilibrium (VLE) of the mixture to calculate the concentration of water existing in the reactor prior to quench, and accounts for the effectiveness of the upstream dehydration process and in the amount of water produced during the polymerization. The technique is a striking improvement over the trial-and-error estimation of the amount of quench water based on human operating experience, and avoids direct measurements of the existing water concentration in the reactor. The result is improved control of PPS particle size and other properties.
    Type: Grant
    Filed: February 22, 2005
    Date of Patent: December 25, 2007
    Assignee: Chevron Phillips Chemical Company LP
    Inventor: Kent Edward Mitchell