Patents Assigned to UG Plus International Inc.
  • Process for removing and recovering copper, silver and zinc from sulfide ores
    Patent number: 5876588
    Abstract: Ores containing copper, zinc, silver in the form of sulfides are treated by a solution of sulfurated sulfite ions and ammonium ions in order to remove most of the metals from the sulfide ores. This treatment renders the resulting gold bearing ores much more amenable to cyanide extraction. Dissolved metals are reclaimed by appropriate techniques, such as electrowinning or liquid-liquid extraction, and the solution of sulfurated sulfites and ammonia is recycled for further lixiviation of fresh ores.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: March 2, 1999
    Assignee: UG Plus International Inc.
    Inventors: Jean-Marc Lalancette, Hugues Menard, Regina Zamojska