Simulation of the Kinetics of Oxidation of Saturated Hydrocarbons on Pt

The steady-state kinetics of C3H8 oxidation on Pt are calculated assuming the process to be limited by concerted dissociative adsorption of C3H8 on vacant sites near adsorbed oxygen atoms (with breaking of a C–H bond and formation of OH). The results, obtained by using (1) the ideal model implying Langmuir adsorption, (2) a model based on the assumption that the saturation oxygen coverage is lower than one monolayer, and (3) a model taking into account adsorbate–adsorbate lateral interactions, indicate that the latter two models can reproduce the apparent reaction orders with respect to C3H8 and O2, observed experimentally under the lean-burn conditions. Model 3 is preferable because its basis is physically more sound.