Hoechst Aktiengesellschaft

Herbert Kuckertz

Siegbert Rittner

Georg Schaeffer

Bernhard Wojtech

Ernst Horoldt

Richard Grimm

Helmut Gossel

Wilfried Billmann

Josef Rosenfelder

A process for the separation of undesired organic ingredients from waste gases which are formed in the preparation of aromatic intermediates which comprises washing the waste gases with a washing liquid comprising

Process for separating organic constituents from waste gases of the

The invention relates to a process for extracting nitrohydroxyaromatics from aqueous solutions. In this process, the extracting agent used is an amine salt which comprises an aliphatic amine having a total carbon number of 10 to 75 and a strong acid. The amine salt can be employed undiluted or diluted with an organic solvent.

Process for extracting nitrohydroxyaromatics from aqueous solutions

Diphenyl ethers are prepared by Ullmann reaction of alkali metal phenolates with halobenzenes in the presence of basic copper carbonate and/or copper salts of lower aliphatic carboxylic acids as catalysts. These special catalysts have a better catalytic activity than other copper catalysts known for the Ullmann reaction. The diphenyl ethers prepared or obtainable according to the invention are mainly intermediates in diverse fields such as pharmaceuticals or plant protecting agents.

Process for the preparation of diphenyl ethers

Process for preparing acetic anhydride from acetic acid methyl ester and carbon monoxide in the presence of catalysts containing noble metals of the 8.sup.th sub-group of the periodic table or their compounds as well as iodine and/or iodine compounds.

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Kelkheim, Germany

Herbert Kuckertz