Hoechst Aktiengesellschaft

Harald Berger

Herbert Siegel

Erwin Weiss

Karl-Ernst Quentin

Ludwig Weil

Hans-Jerg Kleiner

Gunter Roscher

Stephen Lachhein

Gunter Schlegel

Dirk Bottger

Manfred Schmidt

Rainer Uhmann

Norbert Dragesser

Rudolf Heumueller

Erich Schaetzer

Manfred Wagner

In the reactor for carrying out chemical reactions with ultrasound, at least three ultrasonic transducers (15) are arranged on the bottom (13) of the reactor (10) and at least six ultrasonic transducers (15) are arranged on the wall (14).

Reactor for carrying out chemical reactions

Process for the preparation of pure propanephosphonic anhydride, which comprises distilling crude, impure propanephosphonic anhydride having an average degree of polymerization of 20 to 200 and containing less than 0.5% by weight of water by heating to 230 to 300.degree. C. under a pressure of 0.1 to 100 mbar, pure propanephosphonic anhydride having an average degree of polymerization of 20 to 60 being obtained.

Process for the preparation of pure propanephosphonic anhydride

The invention relates to an improved process for the preparation of a compound of the formula R.sup.1 -X-SO.sub.2 -NCO in which

Continuous process for the preparation of sulfonylisocyanates

The invention relates to a process for the preparation of vinylphosphonic dichloride through elimination of hydrogen chloride from 2-chloroethanephosphonic dichloride in the presence of catalysts. The catalysts used are tertiary phosphines, quaternary ammonium or phosphonium salts or alkali metal or alkaline-earth metal halides. When triphenyl phosphine is used as the catalyst, the reaction is carried out under reduced pressure at a temperature of 130.degree. to 166.degree. C. and the vinylphosphonic dichloride produced is simultaneously removed by distillation under reduced pressure. When the other catalysts are used, the process can be carried out at atmospheric pressure or reduced pressure and at temperatures of about 130.degree. to 220.degree. C. and the vinylphosphonic dichloride produced can be removed by distillation simultaneously with or subsequent to the reaction.

Process for the preparation of vinylphosphonic dichloride

The invention relates to a process for the preparation of vinylphosphonic dichloride, in which a 2-chloroethanephosphonate of the formula ##STR1## or a mixture of the two esters, is reacted with thionyl chloride at a temperature of 60.degree. to 160.degree. C. in the presence of a catalyst which contains tertiary phosphines, quaternary ammonium or phosphonium salts or alkali metal or alkaline-earth metal halides. During this reaction, any thionyl chloride which may be present is removed by distillation subsequent to this reaction, the mixture remaining is heated to 140.degree. to 200.degree. C., and the vinylphosphonic dichloride produced during this is removed by distillation.

The invention relates to a process for the preparation of 2-chloroethanephosphonic dichloride through reaction of a 2-chloroethanephosphonate of the formula ##STR1## or a mixture of the two esters, with thionyl chloride at a temperature of 60.degree. to 160.degree. C. In this reaction, tertiary phosphines, quaternary ammonium or phosphonium salts or alkali metal or alkaline-earth metal halides are employed as catalysts. The thionyl chloride is introduced into the initially introduced ester.

Process for the preparation of 2-chloroethanephosphonic dichloride

An absorbent for water purification consisting of organic polymers and inorganic absorbing matter having a large surface is obtained by epitactically linking with each other the two components. The absorbent has good absorbing properties with respect to different classes of substances.

Absorbent for water purification and process for preparing same

Drinking water is prepared from crude water containing dissolved lypophilic contaminants by adding polymers of ethylene or substituted ethylenes or copolymers of ethylene with less than 50 % by weight of other ethylenically unsaturated monomers which may contain additionally less than 2 mole % of ethylenes carrying a carboxyl function, and separating the polymer substance containing the lipophilic contaminants.

Growing community of inventors

Kelkheim, Germany

Harald Berger