Patents by Inventor Thomas Keil

Thomas Keil 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).

  • Inhibition of polymerization of vinylaromatic or vinylaliphatic
    Patent number: 5888356
    Abstract: The polymerization of a vinylaromatic or vinylaliphatic compound at elevated temperature in the absence of air is inhibited by processing the vinylaromatic or vinylaliphatic compound in the presence of 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl or 4-acetylamino-2,2,6,6-tetramethylpiperidine-N-oxylalone or in admixture with p-nitrosophenol or 2-methyl-4-nitrosophenol.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: March 30, 1999
    Assignee: Huels Aktiengesellschaft
    Inventors: Thomas Keil, Manfred Kaufhold, Bernd Helpap
  • Process for separating ethylbenzene and styrene by distillation
    Patent number: 5386075
    Abstract: A process for separating ethylbenzene and styrene by distillation is described. The process provides the advantages of a vapor compression/heat pump system, and is designed in such a manner that the energy applied is optimally utilized. The head pressure of the distillation column (1) is controlled in a simple manner, whereby a surprisingly stable column is achieved.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: January 31, 1995
    Assignee: Huels Aktiengesellschaft
    Inventors: Thomas Keil, Wilhelm Huwels, Georg Doll
  • Cyclohexane derivatives containing carboxyl groups
    Patent number: 5153354
    Abstract: Cyclohexane derivatives containing carboxyl groups with the general structure of formula (I): ##STR1## alone or in mixtures with one another, in which the substituents on the cyclohexane ring are in the 1-, 2-, and 4-positions, Z is a --CH.sub.2 --CH.sub.2 -- group or a ##STR2## group, R is an alkyl group with 1 to 10 carbon atoms, and n is an integer of 1 to 3, are obtained by the hydrocarboxyalkylation of 1,2,4-trivinylcyclohexane and are useful as monomers for the formation of polymers.
    Type: Grant
    Filed: November 19, 1991
    Date of Patent: October 6, 1992
    Assignee: Huels Aktiengesellschaft
    Inventors: Wolfgang Schroder, Thomas Keil
  • Process for the preparation of .omega.-enecarboxylic acid esters
    Patent number: 5133903
    Abstract: Hydrocarboxyalkylation of .alpha.,.omega.-dienes with carbon monoxide and an alcohol in the presence of a cobalt compound and a tertiary amine gives .omega.-enecarboxylic acid esters with high selectivity and in good yields.
    Type: Grant
    Filed: February 28, 1989
    Date of Patent: July 28, 1992
    Assignee: Huels Aktiengesellschaft
    Inventors: Reinhold Gull, Thomas Keil
  • Method of manufacturing cyclooctanedicarboxylic acid diesters
    Patent number: 5075492
    Abstract: A method of manufacturing cyclooctanedicarboxylic acid diesters by hydrocarboxyalkylation of 1,5-cyclooctadiene over a cobalt catalyst in the presence of tertiary amines is disclosed.
    Type: Grant
    Filed: May 18, 1990
    Date of Patent: December 24, 1991
    Assignee: Huels Aktiengesellschaft
    Inventor: Thomas Keil