Patents by Inventor Rolf K. Gadd

Rolf K. Gadd 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: 4503017
    Abstract: A process for purifying an acid aqueous solution containing heavy metals by adding sulfide ions to said acid aqueous solution at a first pH lower than 3.4, precipitating a first heavy metal, adding sulfide ions again to said first precipitate containing acid aqueous solution, after adjusting to a pH of higher than 4, to precipitate a second heavy metal, and then removing the resultant first and second precipitates from the acid aqueous solution.
    Type: Grant
    Filed: December 5, 1983
    Date of Patent: March 5, 1985
    Assignee: Boliden Aktiebolag
    Inventors: Rolf K. Gadd, Anna C. Sund-Hagelberg