Patents by Inventor Dieter Schläfer

Dieter Schläfer 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: 7445664
    Abstract: The invention relates to a desublimator for producing particulate, solid aluminum chloride from aluminum chloride vapor, which is formed by a vessel which is closed on all sides and has vertical walls and a feed point for the aluminum chloride vapor and an offtake point for the solid aluminum chloride, wherein the walls of the vessel are formed by flat metal sheets which are welded into a rigid frame so that they can be set into vibration by being struck with a tapper.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: November 4, 2008
    Assignee: BASF Aktiengesellschaft
    Inventors: Dieter Schläfer, Hans-Ulrich Schlimper
  • Patent number: 6890508
    Abstract: The present invention relates to a process for preparing largely HBr-free HCl gas and largely HBr-free aqueous HCl solution, which comprises the following steps: a) providing HBr-containing HCl gas; b) passing the HBr-containing HCl gas through aqueous HCl solution saturated with HCl; c) separating off HBr-containing aqueous HCl solution saturated with HCl; d) if desired, passing the largely HBr-free HCl gas obtained in step b) into water to obtain largely HBr-free aqueous HCl solution; with largely HBr-free aqueous HCl solution produced in step d) being able, if desired, to be recirculated to step b) of the process. The process of the present invention allows high-purity aqueous HCl solution for use in the semiconductor industry to be prepared inexpensively and on an industrial scale. However, the purified HCl gas obtained by means of steps a) to c) can also be used for any other purposes. The invention likewise provides an apparatus for carrying out the process of the present invention.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: May 10, 2005
    Assignee: BASF Aktiengesellschaft
    Inventors: Dieter Schläfer, Josef Guth, Hans-Ulrich Schlimper
  • Patent number: 6770187
    Abstract: The invention relates to an electrolysis cell comprising an anode compartment which comprises an aqueous solution of at least one alkali metal salt, a cathode compartment and a solid electrolyte which separates the anode compartment and the cathode compartment from one another, wherein that part of the surface of the solid electrolyte which is in contact with the anode compartment and/or that part of the surface of the solid electrolyte which is in contact with the cathode compartment has/have at least one further ion-conducting layer.
    Type: Grant
    Filed: February 25, 2002
    Date of Patent: August 3, 2004
    Assignee: BASF Aktiengesellschaft
    Inventors: Hermann Pütter, Günther Huber, Kerstin Schierle-Arndt, Dieter Schläfer, Josef Guth
  • Patent number: 6657091
    Abstract: Alkali metal alkoxides are prepared by reacting alkali metal amalgam with alcohol in the presence of a catalyst comprising iron having a carbon content of at least 0.3% by weight.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: December 2, 2003
    Assignee: BASF Aktiengesellschaft
    Inventors: Kerstin Schierle-Arndt, Hans-Josef Sterzel, Dieter Schläfer, Josef Guth, Holger Friedrich, Peter Zehner
  • Patent number: 6409908
    Abstract: In a process for producing an alkali metal from alkali metal amalgam by electrolysis using an alkali metal amalgam as anode, a solid electrolyte which conducts alkali metal ions and a liquid alkali metal as cathode, the alkali metal amalgam as anode is kept in motion.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: June 25, 2002
    Assignee: BASF Aktiengesellschaft
    Inventors: Günther Huber, Hermann Pütter, Kerstin Schierle-Arndt, Dieter Schläfer, Josef Guth, Bernd Schube, Diethard Lenz
  • Patent number: 6402910
    Abstract: A process for preparing sodium and aluminum chloride electrochemically is described in which, in an electrolytic cell containing aluminum as an anode and sodium as a cathode which are separated from one another by a sodium ion-conducting solid electrolyte, a fused electrolyte essentially containing sodium tetrachloroaluminate is electrolyzed in the anode compartment, aluminum chloride formed in this process is evaporated from the electrolytic cell and sodium is removed from the cathode compartment.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: June 11, 2002
    Assignee: BASF Aktiengesellschaft
    Inventors: Hermann Pütter, Günther Huber, Luise Spiske, Hans Stark, Dieter Schläfer, Gerhard Pforr
  • Patent number: 6368487
    Abstract: An electrolytic cell comprises an agitated, alkali metal amalgam-containing anode, an alkali metal ion-conducting solid electrolyte and a cathode, wherein the solid electrolyte and the cathode are separated from one another by a liquid electrolyte.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: April 9, 2002
    Assignee: BASF Aktiengesellschaft
    Inventors: Günther Huber, Hermann Pütter, Kerstin Schierle-Arndt, Dieter Schläfer, Josef Guth
  • Patent number: 6352660
    Abstract: Composite fibers useful for preparing diaphragms are prepared by (a) mixing a PTFE or PTFE copolymer dispersion or powder with a finely divided inorganic material and a fiber forming material, (b) shear heating the resulting mixture to a temperature at which sheared to PTFE or PTFE copolymer becomes flowable without showing signs of decomposition while removing the dispersion medium, if a PTFE or PTFE copolymer dispersion is used, (c) cooling the mixture to below 70° C., (d) mix shearing the mixture at below 70° C. to form composite fibers.
    Type: Grant
    Filed: October 21, 1998
    Date of Patent: March 5, 2002
    Assignee: BASF Aktiengesellschaft
    Inventors: Holger Friedrich, Ulrich Bröckel, Dieter Schläfer, Klaus-Dieter Hoppe, Kurt Hecky, Peter Palm
  • Patent number: 6287448
    Abstract: A process for producing metallic lithium starting from an aqueous solution of at least one lithium salt comprises the following steps: (I) Production of a lithium amalgam from an aqueous solution of at least one lithium salt; and (II) Electrolysis using an anode comprising the lithium amalgam, a solid electrolyte which conducts lithium ions, and liquid lithium as cathode, wherein the lithium amalgam as anode is kept in motion.
    Type: Grant
    Filed: March 20, 2000
    Date of Patent: September 11, 2001
    Assignee: BASF Aktiengesellschaft
    Inventors: Kerstin Schierle-Arndt, Hermann Pütter, Günther Huber, Dieter Schläfer, Josef Guth
  • Patent number: 6235183
    Abstract: A process for preparing sodium and aluminum chloride electrochemically is described in which, in an electrolytic cell containing aluminum as an anode and sodium as a cathode which are separated from one another by a sodium ion-conducting solid electrolyte, a fused electrolyte essentially containing sodium tetrachloroaluminate is electrolyzed in the anode compartment, aluminum chloride formed in this process is evaporated from the electrolytic cell and sodium is removed from the cathode compartment.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: May 22, 2001
    Assignee: Basf Aktiengesellschaft
    Inventors: Hermann Pütter, Günther Huber, Luise Spiske, Hans Stark, Dieter Schläfer, Gerhard Pforr
  • Patent number: 4837002
    Abstract: Chlorate is removed from aqueous caustic soda by reducing with iron pentacarbonyl and separating off the resulting iron oxide containing precipitate.
    Type: Grant
    Filed: February 22, 1988
    Date of Patent: June 6, 1989
    Assignee: BASF Aktiengesellschaft
    Inventors: Dieter Schlaefer, Wolfgang Kochanek, Bernd Leutner
  • Patent number: 4557818
    Abstract: A gas-evolving metal electrode consists of profiles which are arranged parallel to one another in a horizontal plane and are connected to one another by means of current distributors. The profile surfaces which face the counter-electrode are curved, the curvature at the sides being more pronounced than that in the middle. The profile is terminated above by means of two lateral surfaces tangential to the curvature. The electrode is useful as an anode for mercury cells for the chloralkali electrolysis.
    Type: Grant
    Filed: July 12, 1984
    Date of Patent: December 10, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Hans Roos, Dieter Schlaefer, Hugo Boehn, Knut Bittler, Heinz Kilthau
  • Patent number: 4422921
    Abstract: Bipolar electrodes with graphite as the carrier have a layer of chromium trioxide not less than 10 .mu.m thick on both the anode face and the cathode face.The electrodes are produced by plasma-spraying chromium trioxide powder onto a graphite layer, and can be used as bipolar electrodes in alkali metal chloride electrolysis cells.
    Type: Grant
    Filed: August 16, 1982
    Date of Patent: December 27, 1983
    Assignee: BASF Aktiengesellschaft
    Inventors: Hans Roos, Hugo Boehn, Knut Bittler, Dieter Schlaefer