Catalysts as Sensors—A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment

Catalysts as Sensors—A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment

Sensors that detect directly and in situ the status of automotive exhaust gas catalysts by monitoring the electrical properties of the catalyst coating itself are overviewed. Examples included in this review are the in-situ determination of the electrical impedance of three-way catalysts based on ceria-zirconia solutions and of lean NO(x) traps of earth-alkaline based coatings, as well as appro...

Ceria in Automotive Exhaust Catalysts

Oxygen storage capacities of CeOz, Ce02/A1203, and PMiCe0,/A120~, measured by a pulse injection method, are affected by pretreatment temperature, pulsing temperature, partial pressure of CO, presence of precious metals (PM), and the concentration of CeOz on alumina. They are lowered by higher pretreatment temperature but increase with the pulsing temperature in the range of application. At a pu...

Dynamic Behaviour of NOx Storage Catalysts and Combined Exhaust Gas Aftertreatment Systems

Multiscale Modelling for Automotive Exhaust-Gas Aftertreatment – From the Quantum Chemistry to the Engineering Level

In this work the behaviour of a novel automotive catalytic converter is theoretically investigated using a multiscale-modelling approach. Processes ranging from the nano-scale (chemical reactions) to the macro-scale (transient conversions in a single monolithic channel of a catalyst) are addressed by different modelling techniques. These independent techniques are combined in a hierarchical mul...

Automotive Three-Way Exhaust Aftertreatment under Transient Conditions – Measurements, Modeling and Simulation

In this work a mathematical model for the dynamic thermal and the macrokinetic conversion behavior of a commercial automotive three-way exhaust catalytic converter is developed and parameterized with independent measurements. In spite of its relative simplicity the developed model is comprehensive enough to cover the major phenomena relevant for catalyst conversion under light-off conditions an...