Patents by Inventor Walter Biermann

Walter Biermann 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 reprocessing sulfuric acid from phosphorous purification
    Patent number: 5122359
    Abstract: A process for reprocessing sulfuric acid obtained in the purification of yellow phosphorous, which comprises mixing the contaminated sulfuric acid with hydrogen peroxide and reacting this mixture in a vessel containing hot concentrated sulfuric acid at 110.degree. to 210.degree. C. in the presence of FeSO.sub.4, MnSO.sub.4 or NiSO.sub.4 as a catalyst is described.
    Type: Grant
    Filed: July 25, 1990
    Date of Patent: June 16, 1992
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Werner Pieper, Walter Biermann