Abstract: The invention provides a microstructured, self-cleaning, catalytically active surface with elevations and depressions, comprising a catalytically active material in the depressions.

Abstract: A description is given of a structured packing for a column for carrying out a distillation or reactive distillation which is formed from a three-dimensional body which substantially completely fills the column cross section and which was obtained from two or more differently structured webs of a nonwoven material by winding up or laying one on top of the other and is chemically and mechanically stable under the processing conditions of distillation or reactive distillation.

Abstract: Apparatus for substantially isothermal operation of a heterogeneously catalyzed gas phase reaction involving a pronounced exotherm comprises at least one reactor space (101) having an inlet (131, 141) and an outlet (143), wherein

Abstract: A process for greatly improving the color index of polyhydric alcohols, especially trimethylolpropane, by hydrogenation comprises using, in the hydrogenation, an alcohol which has already been purified by distillation. The catalysts used are those conventionally employed in hydrogenations, preferably copper, nickel, palladium or ruthenium catalysts.

Abstract: Alkynes, dienes, alkenynes and/or polyenes in an olefin-containing hydrocarbon stream are selectively hydrogenated catalytically in the gas phase in at least two reaction zones connected in series without introduction of part of this hydrocarbon stream between the penultimate reaction zone and the last reaction zone, wherein the hydrogen content in the reaction gas mixture upstream of the penultimate reaction zone and the degree of conversion in the penultimate reaction zone are set so that the reaction gas mixture contains at least 0.7% by volume of hydrogen at the outlet of the penultimate reaction zone.

Abstract: Raney alloy catalysts applied to a support are described, said catalysts having an extremely thin layer of Raney alloy with a thickness of 0.01 to 100 &mgr;m. These catalysts are prepared by vapor deposition of the appropriate metals under reduced pressure. They are generally suitable for all known hydrogenation and dehydrogenation reactions and are extremely abrasion-resistant.

Abstract: Alkenes are prepared by partial hydrogenation of alkynes in the liquid phase at from 20 to 250° C. and hydrogen partial pressures of from 0.

Abstract: Alkenes are prepared by partial hydrogenation of alkynes in the liquid phase at from 20 to 250° C. and hydrogen partial pressures of from 0.