Patents by Inventor Hans-Werner Stephan

Hans-Werner Stephan 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: 5531075
    Abstract: In a process to transport acetylene which is dissolved in a solvent in a pressurized, insulated tank, the acetylene-to-solvent mass ratio of the solution is 0.30 at the maximum, whereby the solution has a temperature of up to -55.degree. C. [-67.degree. F.]. The surface of the solution in the tank is covered by a multilayer configuration consisting of pieces of floating material.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: July 2, 1996
    Assignee: Messer Griesheim GmbH
    Inventors: Hartmut Behringer, Siegfried Pottkamper, Hans-Werner Stephan, Gerrit Marcks
  • Patent number: 4757156
    Abstract: Tertiary alkylphosphines of the general formula R.sub.3 P, in which R stands for identical or different, linear, unsubstituted alkyl groups having 3 to 20 carbon atoms, with the proviso however that one of the alkyl groups may be a secondary butyl group, are made by reacting hydrogen phosphide PH.sub.3 with an appropriate alkene or alkenes in stoichiometric excess, if desired, at elevated temperature and under increased pressure in contact with a radical-yielding agent. 2,2'-azobis-(2-methylbutyronitrile) is used as the radical-yielding agent in the absence of whatever alien solvent.
    Type: Grant
    Filed: August 14, 1987
    Date of Patent: July 12, 1988
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Norbert Weferling, Georg Elsner, Hans-Werner Stephan, Friedrich-Karl Frorath
  • Patent number: 4540558
    Abstract: The disclosure relates to a process for removing organic compounds from wet-processed phosphoric acid with the aid of an adsorbant. To this end the disclosure provides for the acid to be heated to at least 250.degree. C. prior to treating it with the adsorbant. The disclosure also relates to an apparatus for carrying out the process.
    Type: Grant
    Filed: July 3, 1984
    Date of Patent: September 10, 1985
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Reinhard Gradl, Hans-Werner Stephan, Gero Heymer, Gunther Schimmel
  • Patent number: 4530769
    Abstract: The disclosure relates to a process for the discontinuous separation of a solid consisting predominantly of carbon black from its aqueous suspension by filtration. To this end, the disclosure provides for use to be made of a tube pressure filter which is operated under a final pressure of 30 to 100 bars.
    Type: Grant
    Filed: March 29, 1983
    Date of Patent: July 23, 1985
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Manfred Wolter, Friedrich-Wilhelm Dorn, Gero Heymer, Hans-Werner Stephan
  • Patent number: 4517163
    Abstract: The disclosure relates to a process for making titanium dioxide concentrates from material containing titanium oxide and iron oxides. More particularly, the titanium oxide-containing material is calcined at temperatures of 870.degree. to 1300.degree. C., and then treated with a chlorine-containing gas at temperatures of 800.degree. to 1300.degree. C., if desired with addition of carbon.
    Type: Grant
    Filed: February 24, 1983
    Date of Patent: May 14, 1985
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Klaus Jodden, Gero Heymer, Hans-Werner Stephan
  • Patent number: 4447400
    Abstract: A device for metering liquid yellow phosphorus into a rotating ball mill for the production of red phosphorus therein includes a stationary outer tubular structure surrounding an inner tubular structure rotatably mounted therein. A valve having a valve rod associated with it is installed within the inner tubular structure near its end close to the ball mill. A plug provided with a central bore receiving the valve rod is installed within the inner tubular structure near its end remote from the ball mill. A bellows surrounds a portion of the valve rod inside the inner tubular structure, the bellows being tightly connected to the plug and valve rod.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: May 8, 1984
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hans-Werner Stephan, Hermann Klein, Klaus Lehr
  • Patent number: 4402812
    Abstract: The disclosure provides an electrolytic cell sealed in gas-tight and liquid-tight fashion. The cell is comprised of a box-shaped cell tank open at its top and provided with at least one intake duct, at least one overflow duct and at least one discharge duct. A cover is placed on the cell tank and two opposed flanges receiving electrode supporting frames are secured to the inside of the cell tank near the upper end thereof. A chemically resistant and electrically insulating coating is applied to the inside of the cover and cell tank and a plurality of semi-circular recessed grooves spaced apart from each other are formed in the upper rim portion of at least one of the side walls of the cell tank, the recessed grooves receiving semi-circular current beams projecting outwardly.
    Type: Grant
    Filed: March 18, 1982
    Date of Patent: September 6, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Herbert Panter, Hermann Klein, Gerhard Nolte, Eberhard Preisler, Hans-Werner Stephan, Gunter Reichert
  • Patent number: 4355010
    Abstract: Phosphorus in vapor form and phosphanes are separated from gas mixtures which consist of carbon monoxide, with or without hydrogen, nitrogen and steam. Concerned are more particularly the off-gases of phosphorus-producing furnaces. To this end, the gas mixture is admixed with at least the stoichiometric amount of oxygen and/or of oxygen-containing gases necessary to achieve conversion of the total phosphorus contained in the gas mixture to oxidation level V. The resulting mixture is introduced into a reaction zone maintained at a temperature within the range 200.degree. to 700.degree. C. and allowed to remain therein over a period of 0.5 to 20 seconds. Resulting phosphorus-V compounds are finally separated from the gas mixture.
    Type: Grant
    Filed: October 29, 1980
    Date of Patent: October 19, 1982
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Klaus Jodden, Friedrich-Wilhelm Dorn, Gero Heymer, Hans-Werner Stephan
  • Patent number: 4330504
    Abstract: The invention relates to an apparatus for making red phosphorus by subjecting molten yellow phosphorus to a thermal conversion reaction in a closed reaction zone. To this end, a hollow shaft-provided and closed ball mill is preheated to a reaction temperature within the range 280.degree. to 590.degree. C. Yellow phosphorus is continuously introduced into the ball mill through the hollow shaft in quantities per unit time which permit the reaction temperature prevailing inside the ball mill to be maintained without supply of heat from the outside. More particularly, decreasing quantities of yellow phosphorous are introduced per unit time at increasing temperature and increasing quantities of yellow phosphorus are introduced per unit time at decreasing temperature within the limits specified. Red phosphorus is allowed to cool inside the ball mill, water is poured over it and the whole is subjected to wet-grinding. An aqueous suspension of red phosphorus is finally removed from the ball mill.
    Type: Grant
    Filed: January 19, 1981
    Date of Patent: May 18, 1982
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Klaus Lehr, Gero Heymer, Hans-Werner Stephan, Ursus Thummler
  • Patent number: 4278647
    Abstract: The invention relates to a process for making aqueous phosphorous acid solutions by admixing an aqueous sodium phosphite solution with hydrochloric acid. More specifically, phosphorous acid solutions substantially free from sodium in hydrochloric acid are produced by introducing hydrogen chloride, into the sodium phosphite solution until the latter is saturated therewith and separating precipitating sodium chloride from the resulting phosphorous acid solution in hydrochloric acid.
    Type: Grant
    Filed: July 25, 1979
    Date of Patent: July 14, 1981
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Klaus Jodden, Hans-Werner Stephan, Gero Heymer
  • Patent number: 4273752
    Abstract: The invention relates to a process for making red phosphorus by subjecting molten yellow phosphorus to a thermal conversion reaction in a closed reaction zone. To this end, a hollow shaft-provided and closed ball mill is preheated to a reaction temperature within the range 280.degree. to 590.degree. C. Yellow phosphorus is continuously introduced into the ball mill through the hollow shaft in quantities per unit time which permit the reaction temperature prevailing inside the ball mill to be maintained without supply of heat from the outside. More particularly, decreasing quantities of yellow phosphorus are introduced per unit time at increasing temperature and increasing quantities of yellow phosphorus are introduced per unit time at decreasing temperature within the limits specified. Red phosphorus is allowed to cool inside the ball mill, water is poured over it and the whole is subjected to wet-grinding. An aqueous suspension of red phosphorus is finally removed from the ball mill.
    Type: Grant
    Filed: February 20, 1980
    Date of Patent: June 16, 1981
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Klaus Lehr, Gero Heymer, Hans-Werner Stephan, Ursus Thummler
  • Patent number: 4163760
    Abstract: Organic phosphines are produced by reacting an alkylene, cycloalkylene or aralkylene in the presence of a free radical-yielding catalyst. More specifically, a pressure reactor, which is provided in its interior with mixing elements, kept free from oxygen, and subdivided so as to comprise an upper cooling zone and a lower reaction zone, is continuously supplied from above with (a) a solution of the alkylene, cycloalkylene or aralkylene and the catalyst in an inert solvent, and (b) a stoichiometric excess of hydrogen phosphide, the said (a) and (b) reactants being supplied jointly with but separately from one another; the (a) and (b) reactants are mixed in the upper cooling zone of the reactor at about 0.degree. to 35.degree. C. and under a PH.sub.3 -pressure of about 80 to 300 bars; the resulting mixture, which travels downwardly in the reactor, is reacted in the lower reaction zone at about 90.degree. to 190.degree. C.
    Type: Grant
    Filed: January 25, 1978
    Date of Patent: August 7, 1979
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Georg Elsner, Gero Heymer, Hans-Werner Stephan
  • Patent number: 4078023
    Abstract: O,O-dialkylthionophosphoric acid chlorides are produced by chlorinating a dialkyldithiophosphoric acid in two stages. In the first stage, the acid is reacted with chlorine in a molar ratio of 1:1.15 to 1:1.50, resulting sulfur is separated, the liquid phase is admixed with a distilled product of a previous batch chlorinated in the second stage and with a further 0.25 to 0.7 mol of O,O-dialkyldithiophosphoric acid per mol of acid initially used, and desirable final product is distillatively separated from said mixture. In the second stage, the distillation residue of the first stage is reacted with a total proportion of 0.9 to 1.0 mol of chlorine per mole of acid initially used, precipitated sulfur is separated from the second stage chlorination product, the liquid phase is distilled off, and resulting distillate is recycled to the first chlorination stage.
    Type: Grant
    Filed: August 24, 1976
    Date of Patent: March 7, 1978
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Bernd Lippsmeier, Hilmar Roszinski, Hans-Werner Stephan
  • Patent number: 3978195
    Abstract: Production of substantially water-insoluble linear ammonium polyphosphates of the general formula (NH.sub.4 PO.sub.3).sub.n, in which n is a number between 10 and 1000. To this end, substantially equimolecular proportions of ammonium orthophosphate and phosphorus pentoxide are reacted by heating them to temperatures within the range 170.degree. and 350.degree.C in the presence of gaseous ammonia. The reaction is effected while continuously and simultaneously mixing, kneading and comminuting the reaction material in a reactor. The reactor is closed, provided with means for the supply of solid feed material, a gas inlet and a gas outlet, a discharge opening for the removal of final product, and with mixing, kneading and comminuting implements which are rotatably secured to the inside of the reactor.
    Type: Grant
    Filed: June 3, 1974
    Date of Patent: August 31, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hermann Schrodter, Hans-Werner Stephan, Gero Heymer
  • Patent number: 3931294
    Abstract: Production of 2-phenyl-ethylene phosphonic acid by reacting styrene with phosphorus pentachloride in a molar ratio of about 1 : 2 in liquid phase and hydrolyzing the resulting complex 2-phenyl-ethylene phosphonic acid tetrachloride with water.
    Type: Grant
    Filed: June 21, 1974
    Date of Patent: January 6, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Theodor Auel, Gero Heymer, Hans-Werner Stephan