Patents by Inventor Eckard Hetzel

Eckard Hetzel 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 separation of residues of toluenediisocyanate production
    Patent number: 4076577
    Abstract: A process for the separation of residues of toluenediisocyanate production from mixtures containing high boiling residues, toluenediisocyanate and solvent by evaporation in said residue at a minimum of 5.degree. C above the boiling point of the higher boiling of the components consisting of toluenediisocyanate and solvent. The mixture is fed into the central portion of an evaporator equipped with a helical agitator operative to provide a material flow moving centrally downwards and peripherally upwards.
    Type: Grant
    Filed: November 3, 1975
    Date of Patent: February 28, 1978
    Assignee: BASF Wyandotte Corporation
    Inventors: Eckard Hetzel, Waldemar Koehler, Georg Friedrich Vock, Rolf Bittler