Hoechst Aktiengesellschaft

Klaus Eichler

Ernst I Leupold

Gunter Roscher

Friedrich Wunder

Hans-Jurgen Arpe

Peter Wirtz

Herbert Baltes

Reinhard Gradl

Ioan Nicolau

Karl-Fred Worner

Peter Horstermann

Horst Langner

Karl-Heinz Schmidt

The invention relates to a process for the preparation of a catalyst which contains palladium and/or compounds thereof and alkali metal compounds, and additionally cadmium compounds and/or gold and/or compounds thereof, on support particles which have been pressed from SiO.sub.2 or an iO.sub.2 -Al.sub.2 O.sub.3 mixture with the aid of a binder which comprises

Carrier catalyst, process for its preparation, and its use for the

The invention relates to a method for making a catalyst which contains palladium and/or its compounds and, if desired, additionally gold and/or gold compounds and which contains as activators alkali metal compounds and, if desired, additionally cadmium compounds on a support which is composed of SiO.sub.2 or an SiO.sub.2 -Al.sub.2 O.sub.3 mixture having a surface area of 50-250 m.sup.2 /g and a pore volume of 0.4-1.2 ml/g and whose particles have a particle size of 4 to 9 mm, 5 to 20% of the pore volume of the support being formed of pores having radii of 200 to 3000 .ANG. and 50 to 90% of the pore volume being formed of pores having radii of 70 to 100 .ANG.. The support particles are compressed with the aid of an Li, Mg, Al, Zn or Mn salt of a C.sub.2 -C.sub.20 carboxylic acid or a mixture of such salts as binder.

Method for making a catalyst

The invention relates to a process for the isolation of vinyl acetate which involves not combining the bottom product of the recylced gas washings with the water-saturated vinyl acetate but rather introducing it to further multiple distillation columns from the gas mixture formed in the reaction of ethylene with acetic acid and oxygen over catalysts containing palladium or palladium compounds in the gas phase.

Process for the isolation of vinyl acetate by distillation

The invention relates to a process for isomerizing monochlorotoluenes or dichlorotoluenes on a zirconium-containing zeolite catalyst of the Pentasil type. Catalysts of this type are distinguished by a particularly high activity coupled with a long service life. In particular, the invention relates to the preparation of a mixture 3-chlorotoluene and 4-chlorotoluene by isomerizing 2-chlorotoluene on zircoium-containing zeolite catalysts of the Pentasil type. The invention also relates to the preparation of a mixture of 2,5-dichlorotoluene and 3,4-dichlorotoluene by appropriate isomerization of 2,4-dichlorotoluene, and to the preparation of a mixture of 2,4-dichlorotoluene and 2,5-dichlorotoluene by appropriate isomerization of 3,4-dichlorotoluene.

Process for isomerizing monochlorotoluenes or dichlorotoluenes

The invention relates to a process for the preparation of vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases on a catalyst which contains palladium and/or compounds thereof and if appropriate additionally gold and/or gold compounds and, as activators, alkali metal compounds and if appropriate additionally cadmium compounds, on a support. The support consists of cylindrical particles with curved front faces. The support material is aerogenic SiO.sub.2 or an aerogenic SiO.sub.2 -Al.sub.2 O.sub.3 mixture having a surface area of 50-250 m.sup.2 /g and a pore volume of 0.4-1.2 ml/g, which is formed to the extent of at least 50% by pores having a diameter of 50-200 .ANG..

Process for the preparation of vinyl acetate

The invention relates to a process for isomerizing alkylthiophenes on zeolite catalysts. In particular, methylthiophene and ethylthiophene can be isomerized by this process. Suitable zeolites are in particular synthetic zeolites of the pentasil, mordenite of faujasite type in their acid form.

Process for isomerizing alkylthiophenes

The invention relates to a process for the isomerization of o-, m- or p-toluidine, or of a mixture of them, on a zirconium-containing zeolite catalyst of the pentasil type. Catalysts of this type are distinguished by particularly high activity and a long useful life. The invention particularly relates to the preparation of m-toluidine by isomerization of o- and/or p-toluidine on zirconium-containing zeolite catalysts of the pentasil type.

Process for the isomerization of o-, m- and/or p-toluidine

The invention relates to a process for the isomerization of halogenated thiophenes on zeolite catalysts. In this manner, in particular, 2-chlorothiophene is isomerized to 3-chlorothiophene and 2-bromothiophene is isomerized to 3-bromothiophene. Particularly suitable zeolites are synthetic zeolites of the pentasil, mordenite or faujasite type in their acid form.

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Eschborn, Germany

Klaus Eichler