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A mathematical model is developed to describe the process of thermal regeneration in diesel-particulate monolithic filters. The model shows that a typical regeneration cycle consists of four stages: preheating, ignition, transportcontrolled combustion, and cooling. The total regeneration time and the peak temperature are the important regeneration characteristics and can be controlled by initial particulate loading, total filtration area, and channel wall thickness.

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Global oxidation kinetics for propylene (C 3 H 6 ), CO, H 2 , and NO were determined over a platinum (Pt) catalyst with simulated diesel exhaust between 200 and 415°C over wide concentration ranges. An integral reactor with high space velocity capability (up to 2 million h -1 ) was used to generate low and moderate conversion data for the rate-generation process. First-order concentration dependency for all the reactants involved in the C 3 H 6 , CO, and H 2 oxidation reactions captured the experimental behavior very well. For the NO-NO 2 reaction, the rate was found to be first order with respect to NO and 0.5 order with respect to O 2 . An overall inhibition term including only the effects of CO and NO for all the reactions was found to be adequate over the range of conditions examined in this study. A simplified 1D reactor code was used to interpret the data and predict exit concentrations. An objective function was defined for the optimization process, which is sensitive to model predictions at all conversion levels. An optimization strategy was also developed to systematically simplify the form of rate expressions and to generate proper initial guesses for each of the intermediate steps.The final rate forms were compared with light-off curves generated on a full-scale reactor mounted on a 1.7 L Isuzu engine at University of Michigan.