Emissions catalysts- Integrating the reaction chemistry

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Current predictions indicate that the use of diesel and lean-burn gasoline engines in passenger vehicles willincrease relative to today's gasoline engines due to their better fuel economy and reduced CO2 emissions.Coincidentally, upcoming environmental policy throughout most of the world is imposing requirements forsignificant decreases in tailpipe NOx, hydrocarbon, CO and particulate emissions from engines. Newtechnologies are therefore being developed for diesel and lean-burn gasoline applications, with specificemphasis on NOx. As hydrocarbon, NOx and particulate must be controlled, technologies for each will bepresent in the exhaust manifold.Micro-kinetic modeling of these systems is typically the ultimate goal for those studying and implementingnew technologies. This avoids the cost prohibitive experiment-based testing method that would necessarilyinclude all engine platforms under many and diverse operating conditions to gurantee performance.Unfortunately, catalyst testing methodology typically consists only of gas in and gas out species measurements.A missing component is the measurement of the chemistry, reaction process and temperature changes in theaxial direction relative to flow. Incorporation of such information into system models enables physicalvalidation and improvements on any micro-kinetic model, or can form the basis for a new micro-kinetic modelof catalytic systems.The University of Waterloo and General Motors of Canada (GM) propose a collaboration, where the uniquereactor abilities at UW will be used to develop system models at GM. This effort will optimize emissionscontrol catalyst efficiency thereby decreasing vehicle emissions and increasing vehicle fuel economy.