Patents by Inventor Donald K. Kofluk

Donald K. Kofluk 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).

  • Recovery of zinc from sulphidic concentrates
    Patent number: 5770170
    Abstract: There is provided a novel class of additives, specifically coals, which are useful in zinc extraction processes involving one or more pressure leach stages carried out at temperatures above the melting point of sulphur. Such processes may include those incorporating a single stage pressure leach, a process involving two stage countercurrent or cocurrent pressure leaches or a multistage leach process for recovering zinc, lead and silver from zinc bearing sulphidic materials which also contain lead and silver.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: June 23, 1998
    Assignee: 698638 Alberta Ltd.
    Inventors: Michael J. Collins, Donald K. Kofluk
  • Hydrometallurgical process for the extraction of copper from sulphidic concentrates
    Patent number: 5730776
    Abstract: There is provided a novel hydrometallurgical process for the extraction of copper from sulphidic concentrates involving an oxidizing pressure leach using dilute sulphuric acid and a carbonaceous additive. The leaching step is carried out preferably at temperatures above the melting point of sulphur but below about 200.degree. C.
    Type: Grant
    Filed: February 27, 1996
    Date of Patent: March 24, 1998
    Assignee: 698638 Alberta Ltd.
    Inventors: Michael J. Collins, Donald K. Kofluk
  • Recovery of zinc from sulphidic concentrates
    Patent number: 5651947
    Abstract: There is provided a novel class of additives, specifically coals, which are useful in zinc extraction processes involving one or more pressure leach stages carried out at temperatures above the melting point of sulphur. Such processes may include those incorporating a single stage pressure leach, a process involving two stage countercurrent or cocurrent pressure leaches or a multistage leach process for recovering zinc, lead and silver from zinc bearing sulphidic materials which also contain lead and silver.
    Type: Grant
    Filed: November 7, 1995
    Date of Patent: July 29, 1997
    Assignee: 698638 Alberta Ltd.
    Inventors: Michael J. Collins, Donald K. Kofluk