Patents by Inventor Norval A. Sinclair

Norval A. Sinclair 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).

  • Method for recovering silver from refractory manganese ores
    Patent number: 5055130
    Abstract: A method for recovering silver from a refractory manganese dioxide-silver ore. The ore is contacted with an effective amount of a culture of direct manganese-reducing Bacillus polymyxa bacteria. The ore-bacteria mixture is maintained at an approximately neutral pH until a sufficient amount of the manganese dioxide in the ore is reduced from Mn(IV) to Mn(II). The silver present in the ore is then recovered by conventional methods such as cyanide leaching.
    Type: Grant
    Filed: May 1, 1990
    Date of Patent: October 8, 1991
    Assignee: The Arizona Board of Regents/University of Arizona
    Inventors: Robert G. Arnold, Norval A. Sinclair, James E. Sharp