Patents by Inventor Fred J. Hurst

Fred J. Hurst 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: 4500493
    Abstract: In the reductive stripping of uranium from an organic extractant in a uranium recovery process, the use of phosphoric acid having a molarity in the range of 8 to 10 increases the efficiency of the reductive stripping and allows the strip step to operate with lower aqueous to organic recycle ratios and shorter retention time in the mixer stages. Under these operating conditions, less solvent is required in the process, and smaller, less expensive process equipment can be utilized. The high strength H.sub.3 PO.sub.4 is available from the evaporator stage of the process.
    Type: Grant
    Filed: June 16, 1983
    Date of Patent: February 19, 1985
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Fred J. Hurst, Jr.
  • Patent number: 4432945
    Abstract: An improvement in effecting uranium recovery from phosphoric acid solutions is provided by sparging dissolved oxygen contained in solutions and solvents used in a reductive stripping stage with an effective volume of a nonoxidizing gas before the introduction of the solutions and solvents into the stage. Effective volumes of nonoxidizing gases, selected from the group consisting of argon, carbon dioxide, carbon monoxide, helium, hydrogen, nitrogen, sulfur dioxide, and mixtures thereof, displace oxygen from the solutions and solvents thereby reduce deleterious effects of oxygen such as excessive consumption of elemental or ferrous and accumulation of complex iron phosphates or cruds.
    Type: Grant
    Filed: November 4, 1981
    Date of Patent: February 21, 1984
    Assignee: The United States of America as represented by the Department of Energy
    Inventors: Fred J. Hurst, Gilbert M. Brown, Franz A. Posey
  • Patent number: RE31686
    Abstract: A reductive stripping flow sheet for recovery of uranium from wet-process phosphoric acid is described. Uranium is stripped from a uranium-loaded organic phase by a redox reaction converting the uranyl to uranous ion. The uranous ion is reoxidized to the uranyl oxidation state to form an aqueous feed solution highly concentrated in uranium. Processing of this feed through a second solvent extraction cycle requires far less stripping reagent as compared to a flow sheet which does not include the reductive stripping reaction.
    Type: Grant
    Filed: January 9, 1974
    Date of Patent: September 25, 1984
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Fred J. Hurst, David J. Crouse
  • Patent number: D281039
    Type: Grant
    Filed: December 23, 1982
    Date of Patent: October 22, 1985
    Inventor: Fred J. Hurst