Patents by Inventor GEORGES KOUMBA YOYA

GEORGES KOUMBA YOYA 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).

  • ORGANOSOLV PROCESS FOR THE EXTRACTION OF HIGHLY PURE LIGNIN AND PRODUCTS COMPRISING THE SAME
    Publication number: 20190062359
    Abstract: A highly pure lignin comprising a lignin content of at least 97% and characterized by a low carbohydrate content and substantially no sulfur content is disclosed herein. An organosolv process for extracting the highly pure lignin is also disclosed herein. The process comprises pretreating a lignocellulosic material in a first polar protic solvent, to remove extractive compounds and to provide a pretreated lignocellulosic material; and treating the pretreated lignocellulosic material with a Lewis acid in a second polar protic solvent.
    Type: Application
    Filed: June 9, 2016
    Publication date: February 28, 2019
    Applicant: UNIVERSITE LAVAL
    Inventors: Tatjana STEVANOVIC, Georges KOUMBA YOYA
  • Process for depolymerization of lignin by laccases
    Patent number: 10059731
    Abstract: A method for depolymerization of lignin includes oxidizing non-phenolic lignin by putting into presence, in at least one solvent, non-phenolic lignin, laccase, redox mediator and a source of oxygen, whereby a mixture including oxidized non-phenolic lignin is obtained, and further includes depolymerization of the oxidized non-phenolic lignin thereby obtained, by adding an oxidizer. The non-phenolic lignin is obtained from phenolic lignin by functionalization of phenol functions of the phenolic lignin.
    Type: Grant
    Filed: November 26, 2014
    Date of Patent: August 28, 2018
    Assignees: Institut Polytechnique de Bordeaux, Université de Bordeaux, Centre national de la recherche scientifique
    Inventors: Stéphane Grelier, Georges Koumba Yoya
  • PROCESS FOR DEPOLYMERIZATION OF LIGNIN BY LACCASES
    Publication number: 20160376300
    Abstract: A method for depolymerization of lignin includes oxidizing non-phenolic lignin by putting into presence, in at least one solvent, non-phenolic lignin, laccase, redox mediator and a source of oxygen, whereby a mixture including oxidized non-phenolic lignin is obtained, and further includes depolymerization of the oxidized non-phenolic lignin thereby obtained, by adding an oxidizer. The non-phenolic lignin is obtained from phenolic lignin by functionalization of phenol functions of the phenolic lignin.
    Type: Application
    Filed: November 26, 2014
    Publication date: December 29, 2016
    Inventors: Stéphane GRELIER, GEORGES KOUMBA YOYA