Global Kinetic Model of a Three-Way-Catalyst-Coated Gasoline Particulate Filter: Catalytic Effects of Soot Accumulation

Journal article, 2021

In the present study, a global kinetic model of three-way-catalyst-coated gasoline particulate filters was developed to understand the relevant kinetic mechanisms taking place both in clean and real soot-loaded filters. The model involves reaction rate expressions for CO, C2H4, and C7H8 conversion over a model Pd/CeZr/Al2O3 catalyst, hydrothermally treated at 650 °C. Particularly, a new rate expression was proposed for ethylene based on the distinctive experimental trends observed for this hydrocarbon. The model predicted satisfactorily the conversion of all three reductants under different experimental conditions. The soot inhibition effect was also modeled by the reduction of the number of active sites. Interestingly, ethylene was less affected compared to other reductants by the presence of soot due to the formation of less stable and more reactive species on the catalyst surface.