Patents by Inventor Herbert Ressel

Herbert Ressel 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 making crude phosphoric acid
    Patent number: 4780294
    Abstract: Crude phosphoric acid is made by subjecting crude phosphate ore containing sulfide to processing treatment with a mineral acid in a closed system comprised of a processing reactor, a filtering zone and an off-gas scrubbing zone. To this end, a soluble compound of a metal forming difficultly soluble sulfides in the respective acid medium is added either(A) during the processing operation the phosphate ore is subjected to or(B) during the scrubbing operation the off-gas is subjected toand the resulting sulfide precipitate is filtered off in case (A) together with further matter precipitated during the processing operation and, in case (B) separated from the scrubbing liquid.
    Type: Grant
    Filed: February 3, 1987
    Date of Patent: October 25, 1988
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunther Schimmel, Friedrich Kolkmann, Reinhard Gradl, Herbert Ressel
  • Apparatus for reducing iron and vanadium in phosphoric acid solution
    Patent number: 4705671
    Abstract: Apparatus for reducing iron and vanadium in phosphoric acid solution with the aid of a granular reductant. The apparatus is comprised of a drum rotatable around its transverse axis. It is partially filled with the granular reductant and provided with inlets for supplying the phosphoric acid solution, the granular reductant and an inert gas, and also with a reaction product outlet.
    Type: Grant
    Filed: October 1, 1985
    Date of Patent: November 10, 1987
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Herbert Ressel, Wilhelm Westphal
  • Process for making wet-process phosphoric acid
    Patent number: 4683127
    Abstract: Wet-process phosphoric acid is made by subjecting a phosphate ore to processing treatment with a mineral acid resulting in the formation of a processed suspension. The formation of silicofluorides is obviated by adding, either to the phosphate ore or the processed suspension, a quantity of an aluminum compound soluble in phosphoric acid sufficent for the processed suspension to present an aluminum concentration of 0.3 to 1.0 wgt %, based on P.sub.2 O.sub.5.
    Type: Grant
    Filed: February 5, 1986
    Date of Patent: July 28, 1987
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Friedrich Kolkmann, Herbert Ressel, Reinhard Gradl, Gunther Schimmel
  • Process for reducing iron and vanadium in phosphoric acid solution
    Patent number: 4642224
    Abstract: Iron and vanadium is phosphoric acid solution are reduced. To this end, the phosphoric acid solution is contacted with ferrophosphorus which is used as the reductant.
    Type: Grant
    Filed: October 1, 1985
    Date of Patent: February 10, 1987
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Herbert Ressel, Hans Haas, Johannes Krause
  • Process for defluorinating alkali metal phosphate solutions
    Patent number: 4620966
    Abstract: The disclosure relates to a process for defluorinating alkali metal phosphate solutions. To this end, the disclosure provides for an alkali metal phosphate solution neutralized to a pH-value of more than 6 and pre-purified to be stirred at 60.degree. to 120.degree. C. into an alkaline earth metal compound. Alkaline earth metal compounds with a solubility in water of less than 5 g/l are used in the form of particles of which more than 50% have a size of less than 8 .mu.m. After a reaction period of 0.5 to 4 hours, the precipitate obtained is separated from the purified alkali metal phosphate solution.
    Type: Grant
    Filed: June 11, 1984
    Date of Patent: November 4, 1986
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunther Schimmel, Herbert Ressel, Gero Heymer, Reinhard Gradl