Patents by Inventor Guenter Siegemund

Guenter Siegemund 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 the preparation of 1,1,1,2-tetrafluoroethane
    Patent number: 6288293
    Abstract: The invention relates to a process for the preparation of 1,1,1,2-tetrafluoroethane from 1,1,1-trifluoro-2-chloroethane and hydrogen fluoride in the gas phase, in which a catalyst containing chromium and magnesium is used which is obtainable by precipitating chromium(III) hydroxide by reacting 1 mol of a water-soluble chromium(III) salt with at least 1.5 mol of magnesium hydroxide or magnesium oxide in the presence of water, the reaction mixture is made into a paste containing chromium hydroxide and a magnesium salt, and the paste is then dried and treated with hydrogen fluoride at temperatures of 20 to 500° C.
    Type: Grant
    Filed: June 21, 1993
    Date of Patent: September 11, 2001
    Assignee: Solvay (Societe Anonyme)
    Inventors: Wolfgang Wanzke, Günter Siegemund, Wilfried Schmieder
  • Process for the preparation of 2H-heptafluoropropane
    Patent number: 5912392
    Abstract: Process for the preparation of 2H-heptafluoropropane from hexafluoropropene and hydrogen fluoride in an apparatus equipped with bubble columns fitted with flow resistances, in which a liquid hydrofluoride of an organic base circulates.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: June 15, 1999
    Assignee: Solvay (Societe Anonyme)
    Inventors: Helmut Vollmueller, Raimund Franz, Guenter Siegemund