Patents by Inventor Graeme W. Norval

Graeme W. Norval 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).

  • Fluoride removal from sulphuric acid
    Patent number: 5324499
    Abstract: A process for the reduction in fluoride concentration in a fluoride-contaminated sulphuric acid which process comprises treating said sulphuric acid with a silicon compound to produce silicon tetrafluoride, and removing said silicon tetrafluoride to produce a purer sulphuric acid having a substantially reduced fluoride concentration. The process is of particular use for the removal of fluoride from waste sulphuric acid in the copper smelting industry to meet environmental concerns.
    Type: Grant
    Filed: September 7, 1993
    Date of Patent: June 28, 1994
    Assignee: Chemetics International Co. Ltd.
    Inventors: Lynda G. Sturgeoff, Graeme W. Norval, Frederick S. Przystal, Andrew E. Yethon