Patents by Inventor Donald H. Alexander

Donald H. Alexander 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).

  • Publication number: 20100320156
    Abstract: The present invention provides a method for oxidizing a substance (e.g., in a waste stream, drinking water, a paper pulp slurry, or on a surface), which uses free radicals and reactive species generated from multiple oxidants. The method comprises combining peroxynitrite or peroxynitrous acid and at least one additional oxidizing agent for a period of time sufficient to oxidize the substance of interest. The peroxynitrite or peroxynitrous acid preferably is formed by irradiation of nitrate ion and/or nitric acid (e.g., with UV or gamma rays). The yield of free radicals and reactive species, which are the intermediate species that perform the oxidation may be increased by addition of a catalysts, electromagnetic radiation, sonic waves, and/or electrolysis.
    Type: Application
    Filed: January 25, 2007
    Publication date: December 23, 2010
    Inventors: Charles O. Olaiya, Jennifer E. Holland, Donald H. Alexander, Robert S. Reimers
  • Patent number: 5679231
    Abstract: A hemodialysis apparatus separates constituents from blood plasma utilizing layered gel membranes of differing permeabilities configured as a U-tube. Physical filter pressing of blood plasma is accomplished by pinching gel beds along the U-tube axis where localized pressure rise and centrifugal forces are established. The U-tube fold also establishes chemical countercurrent pumping across the gel beds. Capillary and electroosmotic gel filtration further accomplishes selective chemical removal and readsorption.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: October 21, 1997
    Inventors: Donald H. Alexander, Nabil Morcos
  • Patent number: 5547583
    Abstract: Metals and organics are extracted from solution by co-precipitating them with a gel comprising aluminum hydroxide and a complexing agent such as EDTA. After the gel is processed to remove the metals and organics, it can be recycled for further use by dissolving it in a high-pH solution, leaving no secondary waste stream. A number of alternative complexing agents perform better than EDTA.
    Type: Grant
    Filed: November 30, 1994
    Date of Patent: August 20, 1996
    Inventor: Donald H. Alexander