Hoechst Aktiengesellschaft

Wacker-chemie Gmbh

Klaus H Kaiser

Herbert Eck

Gunter Roscher

Hellmuth Spes

Dominik Dempf

Klaus Dehmer

Karl Rehn

Hermann Neu

Horst Langner

Karl-Heinz Schmidt

Aladar Lienerth

Werner Becker

Hans Schwarzbauer

Elmar Bethe

Substituted 4-phenoxy-phenols are prepared by adding the corresponding anilines in liquid or molten state together with aqueous sodium nitrite solution in equimolar amounts to excess HCl and introducing the diazonium chloride solution obtained into a boiling mixture of about half-concentrated H.sub.2 SO.sub.4 and an aromatic hydrocarbon.

Process for the preparation of 4-phenoxy-phenols

Process for separating water from a gas mixture, obtained in the manufacture of vinyl acetate by reacting ethylene with acetic acid and oxygen in contact with catalysts containing palladium or palladium compounds in the gaseous phase said gas mixture consisting essentially of acetic acid, vinyl acetate, water, carbon dioxide and ethylene, wherein

Process for separating water from mixtures thereof with vinyl acetate

Hydroquinone mono-phenyl ethers, and their alkali metal salts of the formula ##STR1## in which one of the radicals R.sub.1 and R.sub.2 denotes trifluoromethyl and the other denotes hydrogen or halogen and R.sub.3 represents hydrogen or an alkali metal cation or ammonium cation are prepared by reacting hydroquinone bis-phenyl ethers (bisphenoxybenzenes) of the formula ##STR2## with hydroquinone derivatives of the formula ##STR3## in which Cat denotes an alkali metal cation or ammonium cation and R.sub.4 denotes an alkali metal cation or ammonium cation or a (C.sub.1 -C.sub.4)-alkyl group, in a polar aprotic solvent at temperatures from 120.degree. to 280.degree. C., and optionally, an alkyl group present in the R.sub.4 -position is split off by treatment with an acid.

Process for the manufacture of diphenyl ethers

A process for the purification of crude acetic anhydride by continuous fractional distillation, which comprises first introducing the anhydride into an evaporator, thereafter removing from the evaporator the non-distillable components contained in the crude anhydride, then introducing the distillable components of the anhydride in vapor form into about the central section of a fractionating column, withdrawing from the top of the column the low boiling components together with acetic acid, withdrawing near the bottom of the column a high-percentage of pure acetic anhydride, and separating from the sump of the column up to about 8% by weight based on the initial amount of crude acetic anhydride and returning the same to the evaporator.

Process for the purification of crude acetic anhydride

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Hofheim am Taunus, Germany

Klaus H Kaiser