Patents by Inventor Bernhard Wefringhaus

Bernhard Wefringhaus 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).

  • Novel purification process
    Patent number: 4992599
    Abstract: Crude phenol and also individual phenol fractions from tars or the hydrogenation of coal are purified from contaminating organic bases and sulfur compounds by treating the phenols with phthalic acid anhydride and optionally a quinone and distillation.
    Type: Grant
    Filed: December 13, 1989
    Date of Patent: February 12, 1991
    Assignee: Rutgerswerke AG
    Inventors: Jorg Talbiersky, Bernhard Wefringhaus, Konrad Stolzenberg, Wolfgang Bergins