Patents by Inventor John F. Spisak

John F. Spisak 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).

  • Sequential flotation of sulfide ores
    Patent number: 4460459
    Abstract: A sequential flotation process for the recovery of high-grade concentrates of copper, lead and cobalt-nickel from sulfide ores is provided. A primary grind ore pulp is conditioned with SO.sub.2 as H.sub.2 SO.sub.3 under intense aeration, and the conditioned pulp subjected to sequential flotation, with regrinding and conditioning of a copper rougher concentrate obtained in the first flotation step for copper.
    Type: Grant
    Filed: February 16, 1983
    Date of Patent: July 17, 1984
    Assignee: Anschutz Mining Corporation
    Inventors: Douglas R. Shaw, John F. Spisak, Jerome P. Downey, Gary E. Butts