Patents by Inventor Alfred Nierth

Alfred Nierth 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: 4783553
    Abstract: Diarylguanidines can be isolated from the crude melt from the reaction of arylamines and cyanogen chloride in excellent quality and yield by dissolving the hot melt in water, extracting this solution with at least one polar, water-insoluble, organic compound, and precipitating from the purified aqueous solution the diarylguanidine by adding alkali metal hydroxide.
    Type: Grant
    Filed: March 16, 1987
    Date of Patent: November 8, 1988
    Assignee: Bayer Aktiengesellschaft
    Inventors: Alfred Nierth, Hans Muller
  • Patent number: 4739117
    Abstract: Diaryl guanidines can be obtained in a high degree of purity and in high yields from the crude melt obtained from the reaction of arylamines and cyanogen chloride by dissolving the hot melt in water, extracting this solution with a mixture of at least one water insoluble, apolar hydrocarbon and at least one polar organic compound and precipitating the diaryl guanidine from the purified, aqueous solution by the addition of alkali metal hydroxide.
    Type: Grant
    Filed: December 16, 1986
    Date of Patent: April 19, 1988
    Assignee: Bayer Aktiengesellschaft
    Inventors: Alfred Nierth, Bernhard Scherhag, Reinhard Preuss, Heinz Klose, Salvatore Sabia
  • Patent number: 4444739
    Abstract: An improved process for the production of cyanogen chloride is disclosed according to which liquid hydrocyanic acid and gaseous chlorine are reacted in an aqueous medium. The liquid hydrocyanic acid and chlorine are introduced into a column-shaped reactor via at least one two-component nozzle. The reaction mixture is removed at the head of the column-shaped reactor. Preferably, the hydrocyanic acid is in liquid form and the chlorine is in gaseous form. By the process disclosed, quantitative yields of cyanogen chloride are obtained separately from aqueous solutions of hydrochloric acid of a strength suitable for commercial use.
    Type: Grant
    Filed: April 12, 1982
    Date of Patent: April 24, 1984
    Assignee: Bayer Aktiengesellschaft
    Inventors: Heinrich Konigshofen, Dieter W. Bruck, Alfred Nierth, Marko Zlokarnik, Hans-Jorg Uhlmann