And Injecting Or Pressurizing With Air Or Oxygen Patents (Class 75/734)
  • Thiosulfate generation in situ in precious metal recovery
    Patent number: 7572317
    Abstract: Precious metal recovery by thiosulfate leaching where thiosulfate lixiviant is generated in situ employing elemental sulfur generated from partial oxidation of sulfidic precious metal-bearing feed and/or employing reactants from processing effluent.
    Type: Grant
    Filed: November 10, 2006
    Date of Patent: August 11, 2009
    Assignee: Barrick Gold Corporation
    Inventors: Yeonuk Choi, Peter Kondos, Mark Graham Aylmore, Jacques McMullen, Gus Van Weert
  • Ammonia extraction of gold and silver from ores and other materials
    Patent number: 5114687
    Abstract: Gold and silver are extracted from their elemental state or from complex ores and alloys by leaching them with a solution containing ammonia, ammonium salts and one or more oxidants. The process is particularly effective for refractory gold ores including sulfide and carbonaceous ores.
    Type: Grant
    Filed: December 14, 1990
    Date of Patent: May 19, 1992
    Assignee: South Dakota School of Mines & Technology
    Inventors: Kenneth N. Han, Xinghui Meng
  • Treatment of metal bearing mineral material
    Patent number: 5096486
    Abstract: A process for extracting silver, copper, zinc, arsenic and iron from sulfide materials by leaching under relatively mild oxygen pressure and temperature conditions with sulfuric acid and sodium nitrite.
    Type: Grant
    Filed: December 13, 1990
    Date of Patent: March 17, 1992
    Assignee: Sunshine Precious Metals Incorporated
    Inventors: Corby G. Anderson, Leo E. Krys, Kevin D. Harrison