Bayer Aktiengesellschaft

Josef Haydn

Helmut Fiege

Karlfried Wedemeyer

Udo Birkenstock

Johann Renner

Dieter W Bruck

Adolf Wissner

Feliks Bitners

In the new shaped articles a hollow space or a lumpy inorganic base material is surrounded by a porous silica-containing layer. They can be prepared by applying silica sol or a mixture containing water, silica sol and/or waterglass and, if appropriate, finely pulverulent water-insoluble silica and/or porosity producing agents to a lumpy base material, and, if use is made of organic base materials, then removing these organic base materials by heating. The new shaped articles can be used as support material for catalysts or, if the layer containing the porous silica contains catalytically active substances, as catalysts.

Silica-containing shaped articles and a process for their preparation

A process has been developed for the depyrophorization of pyrophoric metal catalysts, such as Raney nickel catalysts, which comprises treating said pyrophoric metal catalysts in water and/or an organic solvent with an organic nitro compound or a nitroso compound. The catalysts which are obtained according to the process of the invention are useful for carrying out all hydrogenation reaction which can be carried out using the corresponding pyrophoric catalysts. The catalysts obtained are further distinguished by high activity and extended life. They are not contaminated by contact catalyst poisons and can be used essentially without pre-activation.

Process for the depyrophorization of pyrophoric metal catalysts and uses

Process for the depyrophorization of pyrophoric metal catalysts and

A process for the tertiary dealkylation of a tertiary alkyl containing m- and/or p-cresol wherein a tertiary alkyl containing m- and/or p-cresol is continously introduced into a reaction vessel with a small amount of sulfuric acid or an quivalent amount of a sulfonic acid and the reaction vessel contains a high concentration of m- and/or p-cresol or a high boiling phenol which under the prevailing reaction conditions is not substantially vaporized from the reaction mixture. The reaction mixture is maintained at a temperature of no greater than 230.degree. C. The reaction products are withdrawn continuously from the reactor (and separated into its components) and at the same time a small amount of the reaction mixture being withdrawn intermittently or continously from the reactor.

Process for the dealkylation of tert.-alkyl substituted phenols

A process for the continuous preparation of a ditertiary butylcresol wherein m- or p-cresol is reacted with isobutene at elevated temperature using H.sub.2 SO.sub.4 as catalyst wherein the process is carried out stepwise by introducing stepwise into a reaction mixture comprising substantially all of the cresol to be reacted with isobutene. The total amount of isobutene introduced is introduced such that less isobutene is charged in a last stage of the process than in the first stage thereof. Thereafter the catalyst is deactivated.

Process for the continuous preparation of di-tertiary butylcresols

A process for the removal of acids and potential acid-forming agents from a composition containing such acids and potential acid-forming agents and an alkylphenol which composition is obtained by reacting phenols with alkenes in the presence of sulfuric acid or a sulfonic acid, and for treating the effluent thereby obtained, the process being characterized by the steps of:

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Leverkusen, Germany

Josef Haydn