Patents by Inventor Michael Immenkeppel

Michael Immenkeppel 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 eliminating 1-carboxy-1-phosphonocyclopentan-3-one from, or reducing its content in, technical 2-phosphonobutane-1,2,4-tricarboxylic acid using bleaching liquor
    Patent number: 5091562
    Abstract: The present invention relates to a process for eliminating 1-phosphono-1-carboxycyclopentan-3-one (ketone) from, or reducing its content in, an aqueous solution of 2-phosphonobutane-1,2,4-tricarboxylic acid, characterized in that the solution is adjusted to a pH value of > 6 using an aqueous inorganic base, particularly sodium hydroxide, and aqueous bleaching liquor is subsequently added in a molar ratio of NaOCl to ketone of >5:1.
    Type: Grant
    Filed: March 27, 1991
    Date of Patent: February 25, 1992
    Assignee: Bayer Aktiengesellschaft
    Inventors: Michael Immenkeppel, Roland Kleinstuck, Hans-Dieter Block, Hermann Sicius, Peter Schmidt
  • Process for the continuous production of 2-phosphone-butane-1,2,4-tricarboxylic acid and alkali metal salts thereof
    Patent number: 4931586
    Abstract: This invention relates to an improved process for the continuous production of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) and alkali metal salts thereof, in which dialkylphosphite, and ethene-1,2-dicarboxylic acid dialkyl ester, are reacted in the presence of a basic catalyst to form phosphonosuccinic acid tetraalkyl ester, the ester thus obtained is directly reacted with alkyl-acrylate, in the presence of an alkaline catalyst and the reaction product thus obtained is directly hydrolyzed to PBTC or alkali metal salts thereof.
    Type: Grant
    Filed: August 16, 1989
    Date of Patent: June 5, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Roland Kleinstuck, Cornelia Lensch, Michael Immenkeppel, Hans-Dieter Block, Herbert Odenbach