Patents by Inventor Michel Neil

Michel Neil 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).

  • Ozone whitening of synthetic gypsum
    Patent number: 4344925
    Abstract: A process for the whitening of phosphogypsum comprising treating a phosphogypsum in aqueous suspension with an amount of ozone equal to at least 150 parts by weight per million parts by weight of phosphogypsum calculated as Ca SO.sub.4.2H.sub.2 O, the pH of the aqueous suspension being lower than or equal to 3, to yield a whiteness grade of phosphogypsum higher than 75, according to French Standard NF Q 03-038.
    Type: Grant
    Filed: January 15, 1981
    Date of Patent: August 17, 1982
    Assignee: Societe Chimique des Charbonnages
    Inventors: Philippe Pichat, Robert Sinn, Michel Neil