Patents by Inventor Wolfgang Ohlendorf

Wolfgang Ohlendorf 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 the production of trialkyl phosphites
    Patent number: 5710307
    Abstract: This invention relates to a process for the production of symmetrical trialkyl phosphites, which are also known as phosphorus acid trialkyl esters, from phosphorus trichloride and alcohol in the presence of an auxiliary base as an acid-binding agent and a solvent.
    Type: Grant
    Filed: February 19, 1997
    Date of Patent: January 20, 1998
    Assignee: Bayer AG
    Inventors: Wolfgang Ohlendorf, Hans-Dieter Block
  • Production of 2-phosphonobutane-1,2,4-tricarboxylic acid and the alkali metal salts thereof
    Patent number: 5639909
    Abstract: This invention relates to an improved process for the production of 2-phosphono-butane-1,2,4-tricarboxylic acid (PBTC) and the alkali metal salts thereof, in which process dialkyl phosphite, preferably dimethyl or diethyl phosphite, and ethene-1,2-dicarboxylic acid dialkyl ester, in particular the dimethyl or diethyl ester of maleic acid and/or fumaric acid, are initially reacted in the presence of a basic catalyst to yield a phosphonosuccinic acid tetraalkyl ester, the resultant ester is thereupon reacted without further working up with acrylic acid alkyl ester, preferably methyl or ethyl acrylate, in the presence of an alkaline catalyst and the reaction product obtained in this manner is saponified without further working up to yield PBTC or the alkali metal salts thereof. The product when mixed with bleaching lye exhibits reduced chlorine depletion.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: June 17, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christoph Holzner, Wolfgang Ohlendorf, Hans-Dieter Block, Horst Bertram, Roland Kleinstuck, Hans-Heinrich Moretto
  • Process for the recovery of tributyl phosphate from spent hydraulic oils
    Patent number: 5608099
    Abstract: A process for the recovery by distillation of tributyl phosphate (TBPO) from spent hydraulic oils, which are employed particularly in aircraft used for civilian air traffic.
    Type: Grant
    Filed: November 1, 1995
    Date of Patent: March 4, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Hans-G unter Fr ohlen, Hans-Dieter Block, Wolfgang Ohlendorf, Hans-Heinrich Moretto, Peter Schmidt
  • Method of preparing dimethylamine-borane
    Patent number: 5565615
    Abstract: In the preparation of dimethylamine-borane by reacting an alkali metal or alkaline earth metal borohydride with a dimethylammonium salt, the improvement which comprises effecting the reaction in a liquid mixture comprising dimethylamine as a solvent and an additional organic solvent.
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: October 15, 1996
    Assignee: Bayer Aktiengesellschaft
    Inventors: Christoph Holzner, Alfred Wagner, Dietrich Pantke, Hans-Dieter Block, Hans-Heinrich Moretto, Wolfgang Ohlendorf
  • Process for the removal of impurities from hydrazine hydrate
    Patent number: 5484511
    Abstract: A process for the removal of organic impurities and dissolved salts from hydrazine hydrate and aqueous solutions thereof by distillation of the hydrazine hydrate under reduced pressure, passing the hydrazine hydrate vapor through an adsorbent, and condensing the vapor.
    Type: Grant
    Filed: August 26, 1994
    Date of Patent: January 16, 1996
    Assignee: Bayer Aktiengesellschaft
    Inventors: Wolfgang Ohlendorf, Michael Batz, Hans-Heinrich Moretto, Peter Schmidt, Gerhard Jonas
  • Preparation of chromic acid using bipolar membranes
    Patent number: 5096547
    Abstract: The invention relates to a process for the preparation of alkali metal dichromates and chromic acid by the electrolysis of monochromate and/or dichromate solutions in a multi-chamber cell, wherein the anode chamber is shielded from the solution of chromate, dichromate and/or chromic acid by a bipolar ion exchanger membrane.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: March 17, 1992
    Assignee: Bayer Aktiengesellschaft
    Inventors: Helmut Klotz, Rainer Weber, Wolfgang Ohlendorf