Umicore Ag & Co Kg

Umicore Galvanotechnik Gmbh

Dmc2 Degussa Metal Catalysts Cerdec Ag

Dmc2 Degussa Metals Catalysts Cerdac Ag

Martin Votsmeier

Thomas Kreuzer

Egbert Lox

Lothar Mussmann

Dieter Lindner

Jürgen Gieshoff

Martin Roesch

Mamoun Muhammed

Ulrich Goebel

Wilfried Mueller

Ralf Moos

Tassilo Bog

Marcus Pfeifer

Joerg-Michael Richter

Franz Dornhaus

Stephan Eckhoff

Stephan Malmberg

Christopher Harald Onder

Anke Woerz

Lino Guzzella

Matthias Feger

Stefan Franoschek

Dirk Born

Juliane Kluge

Gunter Hagen

Frank-Walter Schütze

Juergen Gieshoff

Juliane Theis

Gregor Beulertz

Othan Adamopoulos

Jorg-Michael Richter

Joerg Michael Richter

Dieter Prasch

Artur Wiser

Gerhard Fischerauer

Sebastian Reiss

Frank Schütze

Othon Adamopoulos

Roman Moeller

Wilfried Dipl-Ing Müller

Martin Rösch

Anke Wörz

The invention is directed to a method for determining the state of aging of a catalytic converter (). The disclosed method functions in a non-contacting manner as resonances formed when the catalytic converter () located in a housing is excited with high-frequency electromagnetic waves are analyzed.

Method for detecting the degree of aging of catalytic converters

The present invention relates to a process for determining the state of an exhaust-gas purification device. The exhaust-gas purification device is one which can store gas and/or particles. By means of the proposed process, it is for example possible for the loading state of the exhaust-gas aftertreatment system, for example the oxygen storage state of a catalytic converter which is provided with an oxygen-storing material, such as for example a three-way catalytic converter, to be analyzed. The present process operates contactlessly through the analysis of resonances which arise upon the excitation of the catalytic converter using the purification device as microwave cavity resonator.

Method for condition determination of an exhaust-gas purification system

The present invention relates to an exhaust-gas aftertreatment system which comprises a preferably catalytically active particle filter (wall-flow filter) which is followed in turn by a throughflow monolith (flow-through monolith) which is preferably provided with a catalytically active function. Both components have the same storage functions for gaseous substances present in the exhaust gas of internal combustion engines. The system is suitable in particular for the simultaneous removal of particles and pollutants from the exhaust gas of both predominantly lean-operated internal combustion engines and also of internal combustion engines operated predominantly with a stoichiometric air/fuel mixture. Likewise described is a process for the production and the use of such a system for exhaust-gas aftertreatment.

Exhaust-gas aftertreatment system with catalytically active wall-flow filter with storage function upstream of catalytic converter with identical storage function

Described is a method for cleaning the exhaust gases of internal combustion engines, which method is suitable for reducing harmful gases and particle emissions. Here, the exhaust gas to be cleaned is conducted, under operating conditions, with a discontinuous profile of the air ratio &#x3bb; across a wall-flow filter substrate which comprises a catalytically active coating containing one storage material. The storage material is suitable for temporarily storing one or more exhaust-gas components under certain operating conditions and releasing said exhaust-gas components again in a targeted fashion in the event of a suitable change in the operating conditions. The coating is configured such that the component has a gradient of the storage material concentration and/or of the total coating amount, with the highest concentration of the storage material in the longitudinal direction of the component being present on the inflow side. At least 60% by weight of the storage material in relation to its total amount is present in the walls between inflow and outflow ducts, and at least 50% by weight of the storage material in relation to its total amount is present in a first, inflow-side zone in the wall-flow filter substrate.

Method for cleaning internal combustion engine exhaust gases

When a nitrogen oxide storage catalyst is being regenerated, the regeneration may be terminated for example as a result of a premature load change in the engine, which can lead to incomplete emptying of the storage catalyst. The residual filling level which remains in the catalyst following an incomplete regeneration of this nature is used as the starting value for calculation of the filling level during the next storage phase. After incomplete regeneration, the nitrogen oxide conversion rate is initially greater than would be expected, on account of the residual filling level. By taking this increased conversion rate into account when calculating the filling level during the storage phase, it is possible to further improve the accuracy of the calculation.

Method for determining the instant at which a nitrogen oxide storage catalyst is switched from the storage phase to the regeneration phase and for diagnosing the storage properties of this catalyst

The invention describes a method for determining the light-off temperature of a catalytic converter on board a vehicle. The aging condition of the catalytic converter is determined by means of the method. To test the catalytic converter, the latter is loaded for example with a CO/HC test pulse. During the combustion of the additional CO and HC on the catalytic converter, an axial temperature profile is generated. The position of the maximum of said temperature profile along the catalytic converter is dependent on the current light-off temperature. The temperature profile travels through the catalytic converter and can be measured at the outlet of the catalytic converter as a time-dependent profile. The original axial temperature profile can be inferred from the time-dependent profile. Using a calculation program, the current light-off temperature of the catalytic converter on the vehicle can be determined. The method has the advantage that the test can take place at exhaust-gas temperatures considerably higher than the light-off temperature. In this way, it is ensured that the test pulse does not lead to increased pollutant emissions.

Method for verifying the aging condition of a catalytic converter on board a vehicle

The present invention describes an exhaust-gas purification system for an internal combustion engine made of an oxidation catalyst arranged close to the engine, a subsequent hydrocarbon adsorber and a particulate filter arranged downstream thereof and provided with another oxidation catalyst. The oxidation catalyst ensures that emission limits with respect to carbon monoxide and hydrocarbons are satisfied in normal driving mode. During operating states with exhaust-gas temperatures below about 200&#xb0; C., the oxidation catalyst can no longer oxidize carbon monoxide and hydrocarbons. Instead, the hydrocarbons are adsorbed by the hydrocarbon adsorber during these operating phases. In order to initiate the periodical regeneration of the particulate filter, the exhaustgas temperature of the internal combustion engine is raised by engine modifications. The increased exhaust-gas temperature leads to desorption of the previously stored hydrocarbons, which are then burned at the oxidation catalyst of the particulate filter, thereby supporting the regeneration of the particulate filter.

Exhaust-gas purification system with particulate filter and method of operation thereof with improved regeneration of the particulate filter

This invention relates to a method of operating a catalyst for treating the exhaust gas of an internal combustion engine, the catalyst comprising, in addition to catalytically active noble metals, also storage components for storing hydrocarbons. During engine operating phases at low exhaust-gas temperatures, such a catalyst stores the hydrocarbons contained in the exhaust gas without burning them. When the exhaust-gas temperature rises, these hydrocarbons are desorbed again and then oxidized at the catalytically active noble metals. This process can lead to uncontrolled, vigorous combustion of the hydrocarbons stored on the catalyst and, therefore, damage to the catalyst. According to the invention, this damage is avoided by continuously calculating the respective loading of the storage components with hydrocarbons and repeatedly regenerating the storage components depending on the loading by temporarily raising the exhaust-gas temperature before damage to the catalyst can occur.

Method of operating a catalyst which includes components for storing hydrocarbons

An oxygen storage material comprising cerium oxide and at least one second oxide of a metal Mis disclosed as well as a process for manufacturing the material and the use of this material in an exhaust gas cleaning catalyst. In a preferred embodiment the oxygen storage material comprises particles from a Ce/Mmixed oxide solid solution coated with an oxide of another metal M. Metal Me.g. can be calcium or zirconium while metal Mmost preferably is aluminum.

Oxygen storage material, process for its preparation and its application in a catalyst

An oxygen storage material based on cerium oxide with at least one other oxide of the metals silicon and zirconium, wherein the cerium oxide and the other oxides are present in the form of a mixed oxide. The material is obtainable in that hydroxidic precursors of the mixed oxide are first prepared in a manner known per se using a wet-chemical route, these precursors are optionally dried at temperatures between 80 and 300&#xb0; C. and the dried precursors are then treated under a hydrogen-containing atmosphere at a temperature between 600 and 900&#xb0; C. for a period of 1 to 10 hours. The reductive thermal treatment endows the material with a greatly improved dynamic behavior as compared with conventional calcination in air.

Oxygen storage material based on cerium oxide, a process for its preparation and its use

A starter catalyst for the purification of the exhaust gases from internal combustion engines, which include palladium on aluminum oxide and of barium oxide, as well as a process for its production. The barium oxide and palladium are together deposited in a finely divided state on the supporting material aluminum oxide and the average particle size of the palladium crystallites is between 3 and 7 nm. The small crystallite size of palladium and the barium oxide likewise deposited in finely divided state on the supporting material impart to the catalyst a high activity and long-term stability to high temperature stresses.

Exhaust-gas purification catalyst to be used close to the engine and process for its production

A process is provided for operating a three-way catalyst that contains an oxygen storage component, that has a minimum and a maximum filling degree for oxygen and that is located in the exhaust gas line of an internal combustion engine. The air/fuel mixture supplied to the engine is varied in such a way that the filling degree of the oxygen storage component in the catalyst is held within a set-point interval between the minimum and maximum filling degree. According to this process, in order to regulate the air/fuel mixture, migration of the filling degree out of the set-point interval is checked in a test phase in such a way that the filling degree is increased or lowered relative to the instantaneous value (initial value) by short-term enrichment or reduction in richness of the air/fuel mixture supplied to the engine by a certain amount and immediately returned to the initial value by a short-term opposing change in the air/fuel mixture (lean/rich pulse sequence or rich/lean pulse sequence). In the case of a breakthrough of lean or rich exhaust gas through the catalyst during the test phase, the air/fuel mixture is enriched or reduced in richness in order to correct the filling degree, wherein the amount by which the filling degree during the test phase is increased or decreased is such that no breakthrough of lean or rich exhaust gas takes place through the catalyst when the filling degree of the oxygen storage component is within the set-point interval.

Process for operating a three-way catalyst that contains an oxygen-storage component

A process for operating an exhaust gas treatment device in a gasoline engine which is operated mainly with a stoichiometric air/fuel ratio and is operated with a rich-mix air/fuel ratio when accelerating or under full load. The exhaust gas treatment device contains a three-way converter catalyst and a first lambda probe upstream of the catalyst and a second lambda probe downstream of the catalyst. The air/fuel ratio is controlled by using the signal from the first lambda probe, whereas the signal from the second lambda probe is used to check the first lambda probe (trim control) and to diagnose the function of the catalyst. Trim control with the second lambda probe is enabled only when, in the event of rich exhaust gas, the voltage difference between the probe voltage for the second lambda probe and a set point voltage is not larger than a predetermined value.

Process for operating an exhaust gas treatment device for a gasoline engine

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Maintal, Germany

Martin Votsmeier