Patents by Inventor David Crabbe

David Crabbe 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: 4975267
    Abstract: Stable K.sub.2 Fe.sub.22 O.sub.34 in the form of lamellar platelets useful as a dehydrogenation catalyst and a method of manufacturing the same, including the steps of mixing iron oxide and a potassium compound, such as potassium carbonate, preferably in a molar ratio of Fe to K of from 3 to 6 and calcining the mixture at a temperature of at least about 900.degree. C. for at least 15 minutes.
    Type: Grant
    Filed: June 25, 1987
    Date of Patent: December 4, 1990
    Assignee: Columbian Chemicals Co.
    Inventors: James M. Watson, David Crabbe, Thomas S. Coursen, Jr.
  • Patent number: 4963343
    Abstract: Stable K.sub.2 Fe.sub.22 O.sub.34 in the form of lamellar platelets useful as a dehydrogenation catalyst and a method of manufacturing the same, including the steps of mixing iron oxide and a potassium compound, such as potassium carbonate, preferably in a molar ration of Fe to K of from 3 to 6 and calcining the mixture at a temperature of at least about 900.degree. C. for at least 15 minutes.
    Type: Grant
    Filed: December 14, 1987
    Date of Patent: October 16, 1990
    Assignee: Columbian Chemicals Co.
    Inventors: James M. Watson, David Crabbe, Thomas S. Coursen, Jr.
  • Patent number: 4798856
    Abstract: There is provided a pigment concentrate dispersible in plastics and having a substantially improved characteristic extrusion screen life, comprising a dispersion in a resin carrier of an inorganic pigment of the type having a hydrophilic surface, having on its surface in an effective amount a surfactant of the type characterized by an attached polar terminus, in relation to the surface of the pigment, and an unattached nonpolar terminus, in relation to the carrier resin, or of the type characterized by a high molecular weight surface blocking agent. Such pigments include iron oxide pigments, red iron oxide pigment, yellow iron oxide pigment, black iron oxide pigment, divalent ferrite pigments, zinc ferrite pigment, and magnesium ferrite pigment. Such surfactants include dimethyl polysiloxane, isopropyl triisostearoyl titanate, trimethylol propane, trimethylol ethane, and low molecular weight polyethylene.
    Type: Grant
    Filed: November 6, 1987
    Date of Patent: January 17, 1989
    Assignee: Columbian Chemicals Co.
    Inventors: Jorge A. Ayala, George A. Joyce, David Crabbe
  • Patent number: 4221766
    Abstract: This process reduces the soluble iron found in the final effluent of a plant making iron oxide by the Penniman-Zoph scrap process. The finished oxide product slurry is separated from the scrap iron, and the slurry is aerated while the pH is maintained between about 3.0 and 5.0. As the soluble iron is converted to product oxide, the pH of the system rises toward the higher value.
    Type: Grant
    Filed: December 10, 1976
    Date of Patent: September 9, 1980
    Assignee: Cities Service Company
    Inventors: Wilfred A. Pabst, David Crabbe