Nitric oxides and unburned hydrocarbons from automotive engines are major atmospheric pollutants. A strategy based on the simultaneous reduction of NO and oxidation of hydrocarbon can be very effective in aftertreatment. In this study, the various regimes of operation of this selective catalytic reduction process using propene as a representative hydrocarbon, with and without the presence of oxygen, are delineated. Detailed kinetic modeling using quantitative microkinetics for Pt and Rh catalysts is performed. Interesting catalytic features including coking and oxygen poisoning are clearly identified. An optimal operating regime in which the complete conversion of NO and C3H6 occurs in the presence of small amounts of oxygen is highlighted. © 2016 American Chemical Society.