Patents by Inventor Drummond Earley, III

Drummond Earley, III 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: 5683490
    Abstract: Metallic forms of gold and other precious metals can be dissolved and transported (mined) using an aqueous sulfide-bearing leach solution. Maximum sulfur fugacities are achieved in sulfide-bearing solutions under approximately neutral pH and relatively reducing conditions. The optimum chemical conditions are achieved specifically by heating an aqueous sulfide solution such as NaHS, Na.sub.2 S, H.sub.2 S, (NH).sub.4 S, or other suitable forms to temperatures of at least about 100.degree. C. in the presence of excess elemental sulfur. The sulfide dissociates in the solution to form aqueous sulfide species including polysulfide and HS.sup.- which lixivate gold and other precious metals.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: November 4, 1997
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: Drummond Earley, III, Michael E. Berndt