Patents by Inventor Dennis A. Hansen

Dennis A. Hansen 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).

  • Patent number: 5071472
    Abstract: A continuous method is provided for purifying and recovering transition metals such as neodymium and zirconium that become reactive at temperatures above about 500.degree. C. that comprises the steps of contacting the metal ore with an appropriate fluorinating agent such as an alkaline earth metal fluosilicate to form a fluometallic compound, and reducing the fluometallic compound with a suitable alkaline earth or alkali metal compound under molten conditions, such as provided in an induction slag metal furnace. The method of the invention is advantageous in that it is simpler and less expensive than methods used previously to recover pure metals, and it may be employed with a wide range of transition metals that were reactive with enclosures used in the prior art methods and were hard to obtain in uncontaminated form.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: December 10, 1991
    Assignee: The United States of America, as represented by the Secretary of the Interior
    Inventors: Davis E. Traut, George T. Fisher, II, Dennis A. Hansen