Emissions catalysts- Integrating the reaction chemistry

目前的预测表明，柴油和稀燃汽油发动机在乘用车中的使用将相对于今天的汽油发动机增加，因为它们具有更好的燃油经济性和减少的CO2排放。巧合的是，世界上大多数国家即将出台的环境政策都要求显著减少发动机的尾气NOx、碳氢化合物、CO和颗粒物排放。因此，正在开发用于柴油和稀燃汽油应用的新技术，特别强调NOx。由于碳氢化合物、氮氧化物和颗粒物必须得到控制，因此排气歧管中将存在针对每种技术的技术。这些系统的微观动力学建模通常是研究和实施新技术的最终目标。这就避免了成本高昂的基于实验的测试方法，该方法必须包括许多不同操作条件下的所有发动机平台以保证性能。不幸的是，催化剂测试方法通常仅包括气体进入和气体排出物质测量。缺少的组件是相对于流动的轴向方向上的化学、反应过程和温度变化的测量。将这些信息纳入系统模型，使physicalvalidation和任何微观动力学模型的改进，或可以形成一个新的催化系统的微观动力学模型的基础。滑铁卢大学和加拿大通用汽车公司（GM）提出了一项合作，在UW的uniquerecreactor能力将用于开发系统模型在GM。这一努力将优化排放控制催化剂的效率，从而减少车辆排放，提高车辆燃油经济性。

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.