Patents by Inventor Karl-Ludwig Weber

Karl-Ludwig Weber 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).

  • Patent number: 6011179
    Abstract: A process for the production of primary and/or secondary amines from imines or nitriles, comprising an aminating hydrogenation of imine or of nitrile with hydrogen in the presence of ammonia, of a hydrogenation catalyst based on cobalt, nickel, ruthenium or mixtures of these metals and of a base, at a temperature within the range of 50.degree. C. to 200.degree. C. and at a pressure within the range of 0.3 to 30 MPa. The yield of amine is increased by the use of a quaternary ammonium hydroxide as base. Preferably a tetraalkylammonium hydroxide is used in a quantity of from 0.01 to 100 mMol per mol of amine or of nitrile. The process is suitable in particular for the production of isophoronediamine from isophorone nitrile imine.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: January 4, 2000
    Assignee: Degussa-Huls AG
    Inventors: Thomas Haas, Karl Ludwig Weber, Klaus Stadtmuller, Willi Hofen, Rudolf Vanheertum
  • Patent number: 5852217
    Abstract: This invention relates to a process for the production of primary and/or secondary amines from oxo compounds by catalytic imination of the oxo compound with ammonia or a primary amine and subsequent hydrogenation. Imination proceeds according to the invention in the presence of a novel imination catalyst, namely an organopolysiloxane containing sulphonate groups. This imination catalyst is distinguished by elevated activity. The process is in particular suitable for the production of isophorone diamine from isophorone nitrile, wherein it has proved possible to reduce the content of secondary products and to increase yield.
    Type: Grant
    Filed: July 7, 1997
    Date of Patent: December 22, 1998
    Assignee: Degussa Aktiengesellschaft
    Inventors: Thomas Haas, Dietrich Arntz, Karl-Ludwig Weber, Willi Hofen, Stefan Wieland
  • Patent number: 5679860
    Abstract: A process for producing 3-aminomethyl-3,5,5-trimethylcyclohexyl amine (isophorone diamine) from isophorone nitrile. Isophorone nitrile is iminated in a first stage and then the reaction mixture is subjected to aminating hydrogenation in a second stage in the presence of a fixed bed hydrogenation catalyst based on Raney cobalt. The fixed bed hydrogenation catalyst is produced in a special manner by mixing a powdery Co--containing Raney alloy with powdery cobalt, sintering the powdery mixture to shaped moldings and then activating by leaching with alkali hydroxide solution. The yield and/or space-time yield in isophorone diamine production can be increased.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: October 21, 1997
    Assignee: Degussa Aktiengesellschaft
    Inventors: Thomas Haas, Roland Burmeister, Dietrich Arntz, Karl-Ludwig Weber, Monika Berweiler
  • Patent number: 5258515
    Abstract: The invention relates to aqueous solutions of sodium salts of trimercapto-s-triazine whose molar saturation concentration at 0.degree. C. to 40.degree. C. is above the saturation concentration of trimercapto-s-triazine trisodium salt (TMT-Na.sub.3). More than two but less than three hydrogen atoms of the trimercapto-s-triazine are replaced by sodium ions. The solutions preferably contain trimercapto-s-triazine disodium salt (TMT-Na.sub.2) in addition to a little TMT-Na.sub.3. Surprisingly, the water solubility of TMT-Na.sub.2 is greater than that of TMT-Na.sub.3. The solutions represent a suitable supply form for the active substance trimercapto-s-triazine (TMT-H.sub.3) used in the separation of heavy metals The preparation takes place by means of reacting TMT-Na.sub.3 with TMT-H.sub.3 in a molar ratio of 1:greater than 0-less than 0.5, especially 1:0.1 to 1:<0.5 in aqueous solution.
    Type: Grant
    Filed: August 25, 1992
    Date of Patent: November 2, 1993
    Assignee: Degussa Aktiengesellschaft
    Inventors: Klaus Hentschel, Marc Samson, Marcel Vingerhoets, Karl-Ludwig Weber
  • Patent number: 5075444
    Abstract: The disodium salt of trimercapto-s-triazine hexahydrate (TMT-Na.sub.2.6H.sub.2 O) which has a considerably higher water solubility than previously known TMT sodium salts. It is used for separating heavy metals from aqueous phase, especially from waste water.TMT-Na.sub.2.6H.sub.2 O is prepared by reacting TMT-Na.sub.3 .9H.sub.2 O, available from cyanuric chloride, with trimercapto-s-triazine (TMT-Ha.sub.3) in a molar ratio of 2-2.1 to 1 in aqueous medium with subsequent crystallization of the TMT-Na.sub.2 .6H.sub.2 O.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: December 24, 1991
    Assignee: Degussa AG
    Inventors: Klaus Hentschel, Marc Samson, Marcel Vingerhoets, Karl-Ludwig Weber