Patents by Inventor Andrea E. Raddatz

Andrea E. Raddatz 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).

  • Formation of tungsten monocarbide from a molten tungstate-halide phase by gas sparging
    Patent number: 4489044
    Abstract: Tungsten monocarbide is prepared by sparging a molten composition comprising an alkali metal halide and an oxygen compound of tungsten with a gas comprising a gaseous hydrocarbon, particularly methane.
    Type: Grant
    Filed: January 27, 1984
    Date of Patent: December 18, 1984
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: John M. Gomes, Andrea E. Raddatz, Elizabeth G. Baglin
  • Extraction of tungsten from ores
    Patent number: 4167555
    Abstract: Tungsten is extracted from hot springs tungsten ores by means of a process comprising (1) calcining the ore, (2) quenching the calcined ore in aqueous alkaline solution and (3) treating the resulting slurry at elevated temperature and pressure to extract the tungsten values from the ore.
    Type: Grant
    Filed: December 15, 1978
    Date of Patent: September 11, 1979
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: John M. Gomes, Daniel A. O'Keefe, Andrea E. Raddatz
  • Formation of tungsten monocarbide from a molten tungstate-halide phase by gas sparging
    Patent number: RE32612
    Abstract: Tungsten monocarbide is prepared by sparging a molten composition comprising an alkali metal halide and an oxygen compound of tungsten with a gas comprising a gaseous hydrocarbon, particularly methane.
    Type: Grant
    Filed: April 24, 1986
    Date of Patent: February 23, 1988
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: John M. Gomes, Andrea E. Raddatz, Elizabeth G. Baglin