Patents by Inventor Joachim Ritzer

Joachim Ritzer 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 hydrogenating nitroaromatic systems with selected platinum catalysts
    Patent number: 9452970
    Abstract: A method is described for the catalytic hydrogenation of aromatic nitro compounds with hydrogen to the corresponding amines in the presence of a supported catalyst comprising platinum. The method is characterized in that the catalyst comprising platinum has been modified with a tungsten compound and with a phosphorus compound in an oxidation state of <5. High yields and high selectivities are possible with the method.
    Type: Grant
    Filed: September 3, 2013
    Date of Patent: September 27, 2016
    Assignee: ALLESSA GMBH
    Inventors: Doris Neumann, Joachim Ritzer
  • Method for preparing cyclic ketones
    Patent number: 8802897
    Abstract: A method for hydrogenating optionally substituted phenols with one hydroxyl group to cyclohexanones over modified, palladium-comprising supported catalysts. This is possible surprisingly in selected alcoholic solvents with high selectivity. Here it is even possible to recycle the catalysts employed, which hitherto has only been possible with considerable loss of selectivity.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: August 12, 2014
    Assignee: Allessa GmbH
    Inventors: Doris Neumann, Joachim Ritzer, Gunther Effenberger
  • Method for Hydrogenating Nitroaromatic Systems with Selected Platinum Catalysts
    Publication number: 20140066658
    Abstract: A method is described for the catalytic hydrogenation of aromatic nitro compounds with hydrogen to the corresponding amines in the presence of a supported catalyst comprising platinum. The method is characterized in that the catalyst comprising platinum has been modified with a tungsten compound and with a phosphorus compound in an oxidation state of <5. High yields and high selectivities are possible with the method.
    Type: Application
    Filed: September 3, 2013
    Publication date: March 6, 2014
    Inventors: Doris Neumann, Joachim Ritzer
  • Process for preparing substituted benzoyl chlorides
    Patent number: 6844468
    Abstract: The present invention relates to a process for preparing substituted benzoyl chlorides of the formula (1) where R, x and y have the meaning given below, which comprises reacting a benzaldehyde of the formula (2) where R, independently of each other, is identical or different and is an unsubstituted phenyl radical or a phenyl radical that is substituted by halogen, NO2, CN, (C1-C4)alkyl or (C1-C4)alkoxy, or is halogen, NO2, CN, NR?2, OR?, SO2R?, SO2OR?, COR? or CO2R?, where R? is an unbranched or branched C1-C10 alkyl radical, an unsubstituted phenyl radical or a phenyl radical which is substituted by halogen, NO2, CN, (C1-C4)alkyl or (C1-C4)alkoxy, x is 1 or 2 and y is 1, 2 or 3, with a chlorinating agent in the presence of a free-radical initiator and a solvent at from ?20 to +200° C.
    Type: Grant
    Filed: October 3, 2002
    Date of Patent: January 18, 2005
    Assignee: Clariant GmbH
    Inventors: Lars Bierer, Joachim Ritzer, Berthold Schiemenz, Thomas Wessel
  • Process for preparing substituted benzoyl chlorides
    Publication number: 20030130537
    Abstract: The present invention relates to a process for preparing substituted benzoyl chlorides of the formula (1) 1
    Type: Application
    Filed: October 3, 2002
    Publication date: July 10, 2003
    Applicant: Clariant GmbH
    Inventors: Lars Bierer, Joachim Ritzer, Berthold Schiemenz, Thomas Wessel
  • Process for preparing substituted benzoyl chlorides
    Publication number: 20020040158
    Abstract: The present invention relates to a process for preparing substituted benzoyl chlorides of the formula (1) 1
    Type: Application
    Filed: July 26, 2001
    Publication date: April 4, 2002
    Applicant: Clariant GmbH
    Inventors: Lars Bierer, Joachim Ritzer, Berthold Schiemenz, Thomas Wessel