Catalytic Reduction of NO by CO over CuO/SBA-15: Reaction Engineering, Kinetics, and Application to Gasoline Engine Exhaust Treatment

Bhavya Chopra, Rishabh Joshi

Abstract: This study investigates the catalytic reduction of NO by CO over CuO/SBA-15 as a cost-effective alternative to NH3-SCR for gasoline exhaust treatment. A Mars-van Krevelen kinetic model is developed for the Cu2+/Cu0 redox cycle, and literature-derived kinetic parameters are employed to formulate a plug-flow reactor model. Temperature, CO:NO ratio, and gas-hourly-space-velocity effects are analysed for both intrinsic kinetics and effectiveness-factor-corrected behaviour. The catalyst exhibits a light-off temperature near 400-430?C and an optimal CO:NO ratio of approximately 1.5-2. Internal diffusion limitations are shown to be minimal for 50?m particles. The results indicate that CuO/SBA-15 is a promising supplementary NOx abatement technology for CO-rich and oxygen-lean gasoline exhaust streams.

Keywords: CO-SCR, CuO/SBA-15, Mars?van Krevelen kinetics, NOx reduction, plug-flow reactor, gasoline exhaust treatment, internal diffusion, reaction engineering