Patents Assigned to R & O Mining Processing Ltd.
  • Patent number: 5484579
    Abstract: A continuous hydrometallurgical process for conversion of ore derived copper and zinc sulfides into recoverable water soluble sulfates is provided. The process comprises:i) contacting the ore derived copper and zinc sulfides with sulfuric acid and with nitric acid to form a reaction mixture in an acidic solution,ii) maintaining the reaction mixture at a temperature in the range of 110.degree. C. to 170.degree. C. while continuously mixing the reaction mixture,iii) adding sufficient sulfuric acid and nitric acid to the reaction mixture to form a light precipitate and a dark precipitate in the reaction mixture, the light precipitate comprising water soluble sulfate salts of copper sulfate, zinc sulfate and iron sulfate, and the dark precipitate being water insoluble and comprising mainly elemental sulfur and gangue,iv) introducing a source of oxygen to the reaction mixture to promote oxidation in the presence of the nitric acid, of the sulfides to sulfates and to oxidize gaseous NO.sub.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: January 16, 1996
    Assignee: R & O Mining Processing Ltd.
    Inventor: Robert N. O'Brien