Patents by Inventor Gerd Dahlhoff

Gerd Dahlhoff 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).

  • Method for producing &egr;-caprolactam and reactor for the method
    Patent number: 6531595
    Abstract: A method is provided for producing &egr;-caprolactam from cyclohexanone oxime by using a zeolite or non-zeolitic material as a catalyst under gas phase reaction conditions. The method comprises a reaction step converting cyclohexanone oxime into &egr;-caprolactam in the presence of the zeolite or non-zeolitic material; and a regeneration step of treating the zeolite or non-zeolitic material with a non-oxidizing gas at a temperature of from about 100°C. to about 600° C.
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: March 11, 2003
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Wolfgang F. Hölderich, Gerd Dahlhoff, Hiroshi Ichihashi, Keisuke Sugita
  • Process for producing epsilon-caprolactam and apparatus for the process
    Patent number: 6482945
    Abstract: A process is provided for producing &egr;-caprolactam from cyclohexanone oxime. The process comprises a evaporation step of a mixture of cyclohexanone oxime and a solvent by introducing the mixture into a fluidized bed in which inert particles is fluidized by an inert gas, the particles having heat enough to evaporate the mixture; and a rearrangement step of cyclohexanone oxime in the evaporated mixture into &egr;-caprolactam by a gas phase Beckmann rearrangement reaction using a solid catalyst, excluding a catalyst consisting of a boric acid or a boron oxide.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: November 19, 2002
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Wolfgang F. Hölderich, Gerd Dahlhoff, Andre Sbresny, Hiroshi Ichihashi
  • Method for producing epsilon-caprolactam and reactor for the method
    Publication number: 20020042509
    Abstract: A method is provided for producing &egr;-caprolactam from cyclohexanone oxime by using a zeolite or non-zeolitic material as a catalyst under gas phase reaction conditions. The method comprises a reaction step converting cyclohexanone oxime into &egr;-caprolactam in the presence of the zeolite or non-zeolitic material; and a regeneration step of treating the zeolite or non-zeolitic material with a non-oxidizing gas at a temperature of from about 100° C. to about 600° C.
    Type: Application
    Filed: September 27, 2001
    Publication date: April 11, 2002
    Inventors: Wolfgang F. Holderich, Gerd Dahlhoff, Hiroshi Ichihashi, Keisuke Sugita
  • Process for producing epsilon-caprolactam and apparatus for the process
    Publication number: 20020040137
    Abstract: A process is provided for producing &egr;-caprolactam from cyclohexanone oxime. The process comprises a evaporation step of a mixture of cyclohexanone oxime and a solvent by introducing the mixture into a fluidized bed in which inert particles is fluidized by an inert gas, the particles having heat enough to evaporate the mixture; and a rearrangement step of cyclohexanone oxime in the evaporated mixture into &egr;-caprolactam by a gas phase Beckmann rearrangement reaction using a solid catalyst, excluding a catalyst consisting of a boric acid or a boron oxide.
    Type: Application
    Filed: September 28, 2001
    Publication date: April 4, 2002
    Inventors: Wolfgang F. Holderich, Gerd Dahlhoff, Andre Sbresny, Hiroshi Ichihashi