Patents by Inventor Sigrid WEGMANN

Sigrid WEGMANN 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).

  • Method for delignifying and bleaching pulp
    Patent number: 10006169
    Abstract: Process for the delignification and bleaching of pulp, comprising a first bleaching stage with hydrogen peroxide in the presence of a molybdate or tungstate in an acidic aqueous mixture; subsequent to the first bleaching stage, a second bleaching stage with hydrogen peroxide in an alkaline aqueous mixture; and, subsequent to the second bleaching stage, a third bleaching stage with hydrogen peroxide in the presence of a molybdate or tungstate in an acidic aqueous mixture.
    Type: Grant
    Filed: October 15, 2014
    Date of Patent: June 26, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Thomas Dietz, Bernd Hopf, Ralf Grimmer, Sigrid Wegmann, Verena Illhardt
  • METHOD FOR DELIGNIFYING AND BLEACHING PULP
    Publication number: 20160298294
    Abstract: Process for delignifying and bleaching pulp Process for the delignification and bleaching of pulp, comprising a first bleaching stage with hydrogen peroxide in the presence of a molybdate or tungstate in an acidic aqueous mixture; subsequent to the first bleaching stage, a second bleaching stage with hydrogen peroxide in an alkaline aqueous mixture; and, subsequent to the second bleaching stage, a third bleaching stage with hydrogen peroxide in the presence of a molybdate or tungstate in an acidic aqueous mixture.
    Type: Application
    Filed: October 15, 2014
    Publication date: October 13, 2016
    Applicant: Evonik Degussa GmbH
    Inventors: Thomas DIETZ, Bernd HOPF, Ralf GRIMMER, Sigrid WEGMANN, Verena ILLHARDT