Patents by Inventor Wiltrud Schaefer-Treffenfeldt

Wiltrud Schaefer-Treffenfeldt 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).

  • Process for isolating hydroxymonocarboxylic and tricarboxylic acids
    Patent number: 5676838
    Abstract: The invention relates to the removal of hydroxymonocarboxylic acids and tricarboxylic acids from aqueous solutions by adsorption on zeolites with a modulus of up to 400.
    Type: Grant
    Filed: February 9, 1995
    Date of Patent: October 14, 1997
    Assignee: Degussa Aktiengesellschaft
    Inventors: Elfriede Sextl, Akos Kiss, Heike Kinz, Wiltrud Schaefer-Treffenfeldt, Sems Yonsel, Stefan Stockhammer