Bayer Aktiengesellschaft

Sigurd Hartung

Raimund Wambach

Rudolf Braden

Lothar Puppe

Gerd-Michael Petruck

Gerhard Reiss

Kai Rohlk

Adolf Wissner

Hans Knupfer

The invention relates to a process for the removal of m-dichlorobenzene from dichlorobenzene mixtures by chlorination in the liquid phase at elevated temperature in the presence of Friedel-Crafts catalysts, the chlorination being carried out with addition of sulphur, sulphur compounds, iodine and/or iodine compounds and the chlorination mixture then being worked up in the usual way.

Process for the removal of m-dichlorobenzene from dichlorobenzene

A process for the preparation of a trichlorobenzene by chlorination of o-dichlorobenzene in the presence of a catalyst is disclosed. The catalyst comprises aluminum chloride. Preferably an iron or iron chloride containing aluminum chloride catalyst is employed.

Process for the preparation of trichlorobenzenes

A process for the separation of isomeric dichlorotoluenes is described wherein an isomeric mixture of dichlorotoluenes is passed over a zeolite of the X or Y type, non-adsorbed dichlorotoluene is separated off and the adsorbed dichlorotoluene is eluted from the zeolite by contacting the same with an eluant.

Separation process

Process for the preparation of aromatic amines which additionally still contain C-C multiple bonds, characterized in that aromatic nitro compounds which still contain C-C multiple bonds are hydrogenated in the presence of metal sulphides of the formula MeS.sub.x in which x is a number from 1 to 4 and Me represents a metal atom of the group consisting of iron, nickel, ruthenium, rhodium, palladium, rhenium, osmium, iridium and platinum as catalysts, at 20.degree. to 140.degree. C and at 5 to 150 bars hydrogen pressure.

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Cologne, Germany

Sigurd Hartung