Patents by Inventor John E. LeGrange

John E. LeGrange 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).

  • Silver recovery apparatus
    Patent number: 4220320
    Abstract: A silver recovery method and apparatus performing highly specific separation of silver from source material containing organic and inorganic materials, including transition metals, comprising the steps of digesting source material with nitric acid solution to form an acidic reaction mixture; thereafter adding increments of sodium or potassium cyanide solution to the separated liquid phase of the reaction mixture; discontinuing addition of cyanide solution when silver(I) cyanide precipitate ceases to form after incremental additions of cyanide solution; and separating silver(I) cyanide precipitate of high purity from the liquid phase of the reaction mixture.
    Type: Grant
    Filed: November 1, 1979
    Date of Patent: September 2, 1980
    Inventor: John E. LeGrange
  • Silver recovery method
    Patent number: 4218242
    Abstract: A silver recovery method and apparatus performing highly specific separation of silver from source material containing organic and inorganic materials, including transition metals, comprising the steps of digesting source material with nitric acid solution to form an acidic reaction mixture; thereafter adding increments of sodium or potassium cyanide solution to the separated liquid phase of the reaction mixture; discontinuing addition of cyanide solution when silver(I) cyanide precipitate ceases to form after incremental additions of cyanide solution; and separating silver(I) cyanide precipitate of high purity from the liquid phase of the reaction mixture.
    Type: Grant
    Filed: January 2, 1979
    Date of Patent: August 19, 1980
    Inventor: John E. LeGrange