Patents by Inventor Ledell Rigsby

Ledell Rigsby 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).

  • Separation and recovery of metal values from natural bitumen ash
    Patent number: 6306356
    Abstract: High yields of vanadium containing virtually no nickel or magnesium are obtained from natural bitumen ash consisting of up to 5% carbon, more than 95% of water-soluble compounds of vanadium, nickel and magnesium by mixing the ash with water to produce a 20% solids slurry of pH below 6.5 and temperature of 80-85° C. oxidizing any reduced vanadium in the slurry and then separating and removing the resulting polyvanadate precipitate from the liquid phase containing substantially all the nickel and magnesium values of the ash.
    Type: Grant
    Filed: July 14, 1994
    Date of Patent: October 23, 2001
    Assignee: U.S. Vanadium Corporation
    Inventors: Michael R. Woolery, Ledell Rigsby