A Modelling and Simulation Study of Toluene Adsorption in DOC Using AVL Boost

Kinetic modelling of exhaust aftertreatment systems is a topic of extensive research in the automobile sector. This study represents the modelling of catalytic reactions on the surface of platinum dispersed diesel oxidation catalysts. In addition to oxidation reactions in the catalytic converter, a model for hydrocarbon adsorption/desorption on zeolite was adopted and validated with experimental results. The model was further used to simulate the experimental results at two different Pt loadings on the catalyst surface. The simulated results were observed to fit reasonably well with the experimental results at each Pt loading on the catalyst. The adsorption/desorption behaviour on the catalyst surface was found to be affected by Pt loading. The simulation results have shown that Pt atoms might have occupied the active site of zeolite which resulted in the reduction of adsorption/desorption rates. Less Pt loading has caused more storage sites on the zeolite surface and hence, higher adsorption-desorption by the catalyst surface was observed, which was validated by the model. The diffusivity and washcoat thickness have also been verified using simulation and these variables are found within minimum error range when comparing values calculated analytically and from experiments.