Abstract: A process which solves the problem of supplying NO2 in accordance with requirements by means of temperature control of the precatalyst which is decoupled from the operating state of the engine. In an associated apparatus, a precatalyst which contains at least one oxidation component and whose temperature can be controlled independently of the operating state of the engine and an active SCR stage comprising an SCR catalyst with upstream metering facility for a reducing agent from an external source are arranged in series. A particle filter can be arranged between precatalyst and metering facility. The precatalyst preferably additionally contains a nitrogen oxide storage material.

Abstract: An exhaust gas post treatment system for an internal combustion engine, including an intake device for taking hydrocarbons into an exhaust gas pipe carrying the exhaust process gas from the internal combustion engine and a treatment device through which exhaust process gas flows downstream of the intake location and which increases the exhaust process gas temperature by oxidation of the hydrocarbons taken in. An exhaust gas post treatment system and a method for operating the same, in that the treatment device has catalytically coated components, the hydrocarbons are at least partly evaporated in the intake device and are modified chemically by cracking reactions and/or by partial oxidation, and the proportion of platinum, at least in a subregion of the catalytic coating of the components, is less than 50% of the overall mass of all the catalytically active substances in this sub region of the coating.

Abstract: The adherence to future legally obligatory exhaust gas limit values for diesel vehicles in Europe, North America and Japan requires not only the removal of particles but also effective removal of nitrogen oxides from the exhaust gas (‘deNOx’). The ‘active SCR process’ is the preferred method for this. The nitrogen oxide conversions achieved by means of this process are particularly high when an optimal NO2/NOx ratio, preferably 0.5, is set upstream of the SCR catalyst. The invention proposes a process which solves the problem of supplying NO2 in accordance with requirements by means of temperature control of the precatalyst which is decoupled from the operating state of the engine.

Abstract: A process which solves the problem of supplying NO2 in accordance with requirements by means of temperature control of the precatalyst which is decoupled from the operating state of the engine. In an associated apparatus, a precatalyst which contains at least one oxidation component and whose temperature can be controlled independently of the operating state of the engine and an active SCR stage comprising an SCR catalyst with upstream metering facility for a reducing agent from an external source are arranged in series. A particle filter can be arranged between precatalyst and metering facility. The precatalyst preferably additionally contains a nitrogen oxide storage material.

Abstract: Catalyst-coated support, method for producing the same, reactor comprising the same and use thereof. Supports having a catalytic coating comprising at least one porous and cavity-containing catalyst layer are described, cavities being irregular spaces having dimensions greater than 5 ?m in at least two dimensions or having cross-sectional areas of at least 10 ?m2. The catalytic coatings are distinguished by a high adhesive strength and can preferably be used in microreactors.

Abstract: The invention relates to an exhaust gas post treatment system for an internal combustion engine, including an intake device for taking hydrocarbons into an exhaust gas pipe carrying the exhaust process gas from the internal combustion engine and a treatment device through which exhaust process gas flows downstream of the intake location and which increases the exhaust process gas temperature by means of oxidation of the hydrocarbons taken in. The invention specifies an exhaust gas post treatment system and a method for operating such an exhaust gas post treatment system which can be implemented cost-effectively.

Abstract: Supports having a catalytic coating comprising at least one porous and cavity-containing catalyst layer are described, cavities being irregular spaces having dimensions greater than 5 ?m in at least two dimensions or having cross-sectional areas of at least 10 ?m2. The catalytic coatings are distinguished by a high adhesive strength and can preferably be used in microreactors.

Abstract: Supports having a catalytic coating comprising at least one porous and cavity-containing catalyst layer are described, cavities being irregular spaces having dimensions greater than 5 ?m in at least two dimensions or having cross-sectional areas of at least 10 ?m2. The catalytic coatings are distinguished by a high adhesive strength and can preferably be used in microreactors.

Abstract: The adherence to future legally obligatory exhaust gas limit values for diesel vehicles in Europe, North America and Japan requires not only the removal of particles but also effective removal of nitrogen oxides from the exhaust gas (‘deNOx’). The ‘active SCR process’ is the preferred method for this. The nitrogen oxide conversions achieved by means of this process are particularly high when an optimal NO2/NOx ratio, preferably 0.5, is set upstream of the SCR catalyst. The invention proposes a process which solves the problem of supplying NO2 in accordance with requirements by means of temperature control of the precatalyst which is decoupled from the operating state of the engine.

Abstract: Catalyst comprising palladium, gold and alkali metal acetate as catalytically active components on a support, which is modified by means of titanium, iron, lanthanum, cerium, yttrium and/or molybdenum or oxides thereof. It can be used for preparing vinyl acetate monomer.

Abstract: The invention relates to a synthesis reactor and to a method for producing vinyl acetate, in which gaseous ethylene and acetic acid, in addition to oxygen or gases containing oxygen, react catalytically. The inventive synthesis reactor is a wall reactor, in which the catalytic synthesis takes place in a plurality of reaction chambers, whose free flow cross sections measure less than 2000 ?m, preferably 1000 ?m and whose indirectly cooled walls are coated with a palladium-gold catalyst.

Abstract: Supports having a catalytic coating comprising at least one porous and cavity-containing catalyst layer are described, cavities being irregular spaces having dimensions greater than 5 ?m in at least two dimensions or having cross-sectional areas of at least 10 ?m2. The catalytic coatings are distinguished by a high adhesive strength and can preferably be used in microreactors.

Abstract: Granules based on pyrogenically prepared silicon dioxide with the following physico-chemical characteristic data: Average particle diameter: ???10 to 120 ?m BET surface area: ???40 to 400 m2/g Pore volume: ??0.5 to 2.5 ml/g Pore distribution: content of pores of pore diameter <5 nm in the total pore volume of less than 5%, remainder meso- and macropores Tamped density: ?220 to 1,000 g/l Numerical content of particles in the <35% particle size range above the D10 value of the particle size distribution weighted according to volume which have tucks or closed off inner hollow spaces: They are prepared by a procedure in which silicon dioxide is dispersed in a liquid, preferably water, together with one or more auxiliaries, the dispersion is spray dried and the granules are optionally heat-treated and/or silanized. The granules are employed as a catalyst support.

Abstract: A continuous process and apparatus for the production of at least approximately spherical, substantially solid particles, in which the particles are granulated in a circulating fluidized bed. This can be achieved by spraying a suspension or a solution of the solid which forms the particles into a chamber. A drying gas is passed through the chamber at a velocity which is sufficient to effect pneumatic conveying of already partially dried or agglomerated particles. The particles conveyed by the drying gas stream are separated from the exhaust gas stream and returned, at least in part, to the chamber. Particles with a size within the desired particle size range are continuously discharged from the chamber, such that the mass present in the chamber remains constant.