Patents by Inventor Ralf Freyberger

Ralf Freyberger 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 separating off fumaric acid and other minor components during the production of maleic anhydride
    Patent number: 8476463
    Abstract: Processes for decreasing fumaric acid deposits in preparing maleic anhydride by heterogeneously catalyzed oxidation of a hydrocarbon with molecular oxygen. Maleic anhydride is absorbed from the crude mixture in an absorbent in an absorption column and desorbed in a desorption column, the entirety or portion of absorbent depleted in maleic anhydride, for controlled precipitation of fumaric acid, being cooled and/or concentrated by evaporating a portion of absorbent such that the difference between the concentration of fumaric acid in the recycle stream at the outlet of the desorption column under existing conditions and the equilibrium concentration of fumaric acid according to the solubility curve after cooling and/or evaporation of a portion of absorbent is ?250 ppm by weight, and the fumaric acid precipitated as a solid is removed completely or partly from the absorbent recycling system and the fumaric acid-depleted absorbent is recycled completely or partly to the absorption column.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: July 2, 2013
    Assignee: BASF SE
    Inventors: Gunther Windecker, Jens Weiguny, Alexander Weck, Ellen Dahlhoff, Wolf-Steffen Weiβker, Jörg Heilek, Thomas Krug, Ralf Freyberger
  • PROCESS FOR PREPARING TETRAHYDROFURAN
    Publication number: 20110245517
    Abstract: The present invention relates to a process for preparing tetrahydrofuran by absorption of C4-dicarboxylic acids and/or derivatives thereof from a crude product mixture into an organic solvent or water as absorption medium, removal of the absorption medium, catalytic hydrogenation of the resulting C4-dicarboxylic acids and/or derivatives thereof and distillation of the water-comprising crude tetrahydrofuran in at least one distillation column, wherein THF-comprising waste streams from the distillation are catalytically hydrogenated with complete or partial recirculation to the process.
    Type: Application
    Filed: November 5, 2009
    Publication date: October 6, 2011
    Applicant: BASF SE
    Inventors: Gunther Windecker, Jens Weiguny, Alexander Weck, Ellen Dahlhoff, Ralf Freyberger
  • PROCESS FOR SEPARATING OFF FUMARIC ACID AND OTHER MINOR COMPONENTS DURING THE PRODUCTION OF MALEIC ANHYDRIDE
    Publication number: 20110021789
    Abstract: A process for decreasing fumaric acid deposits in the preparation of maleic anhydride by heterogeneously catalyzed oxidation of a hydrocarbon with molecular oxygen, in which the maleic anhydride is absorbed from the crude product mixture in an absorbent in an absorption column and desorbed again in a desorption column, the entirety or a portion of the absorbent depleted in maleic anhydride, for controlled precipitation of fumaric acid, being cooled and/or concentrated by evaporating a portion of the absorbent to such an extent that the difference between the concentration of fumaric acid in the recycle stream at the outlet of the desorption column under the conditions existing there and the equilibrium concentration of fumaric acid according to the solubility curve after the cooling and/or evaporation of a portion of the absorbent is greater than or equal to 250 ppm by weight, and the fumaric acid precipitated as a solid is removed completely or partly from the absorbent recycling system and the fumaric acid-
    Type: Application
    Filed: March 23, 2009
    Publication date: January 27, 2011
    Applicant: BASF SE
    Inventors: Gunther Windecker, Jens Weiguny, Alexander Weck, Ellen Dahlhoff, Wolf-Steffen Weissker, Jörg Heilek, Thomas Krug, Ralf Freyberger