Patents by Inventor Donald A. Luke

Donald A. Luke 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: 5609123
    Abstract: A pet litter composition comprises a particulate substrate having bonded onto its surfaces a fine particulate superabsorbent polymeric material and a particulate soluble polymer to promote clumping. When wetted with urine, the exposed superabsorbent and soluble polymer localise the urine and result in the rapid formation of a strong agglomerate that can easily be removed from the pet litter composition and that disintegrates when added to water.
    Type: Grant
    Filed: August 17, 1995
    Date of Patent: March 11, 1997
    Assignee: Allied Colloids Limited
    Inventors: Donald A. Luke, Geoffrey S. Gagen
  • Patent number: 4325918
    Abstract: Uranium in wet-process phosphoric acid in the tetravalent state is extracted with an alkylphenyl acid phosphate extractant. The uranium in the pregnant extractant is then oxidized to the hexavalent state and stripped with a phosphoric acid stripping solution. Hydrolysis of the extractant is decreased by decreasing the proton concentration of the extractant which results from acidic impurities, e.g., sulfuric acid and fluorosilicic acid, originally present in the wet-process phosphoric acid. The proton concentration of the extractant is reduced indirectly by treating the phosphoric acid strip solution (1) with reagents which react with the acidic impurities to form water and an insoluble precipitate which is removed from the stripping solution; (2) with reagents to neutralize the acidic impurities in the stripping solution; or (3) by passing the stripping solution through a suitable ion exchange column.
    Type: Grant
    Filed: August 31, 1979
    Date of Patent: April 20, 1982
    Assignee: UNC Recovery Corporation
    Inventors: Donald A. Luke, Alex Magdics, Sandra L. Paris, Ralph E. Worthington
  • Patent number: 4289609
    Abstract: The solid organic materials contained in wet-process phosphoric acid are removed by froth flotation in a flotation cell in which the solid organic materials overflow with the foam from the top of the cell and the acid, after passing through the cell, is passed to extraction. The froth flotation process can also be used to remove defoamer and organic soluble materials from the wet-process phosphoric acid. Uranium in the partially purified phosphoric acid product is extracted with a suitable organic extractant, typically a mixture of mono- and di-(alkylphenyl) esters of orthophosphoric acid.
    Type: Grant
    Filed: May 2, 1978
    Date of Patent: September 15, 1981
    Assignee: Uranium Recovery Corporation
    Inventors: Ralph E. Worthington, Donald A. Luke, Stanton L. Reese