Rutgerswerke Aktiengesellschaft

Rutgers Vft Ag

Wolfgang Bergins

Jorg Talbiersky

Konrad Stolzenberg

Bernhard Wefringhaus

For the preparation of 3,5-dimethylphenol by catalytic demethylation of isophorone in the gas phase in the presence of a metal or a metal alloy as catalyst, an isophorone-containing process stream is guided through reaction zones that contain said catalyst, whereby the reactivity of the catalyst varies in the reaction zones and the process stream between these reaction zones is thermostated in zones that do nor contain any catalyst, whereby the residual isophorone is greatly reduced, and the yield of 3,5-dimethylphenol is increased.

Process for preparing 3,5-dimethylphenol

Crude phenol and also individual phenol fractions from tars or the hydrogenation of coal are purified from contaminating organic bases and sulfur compounds by treating the phenols with phthalic acid anhydride and optionally a quinone and distillation.

Growing community of inventors

Castrop-Rauxel, Germany

Wolfgang Bergins