Study of Cu/Mn Catalysts for Coreactions of NH3-SCR and CO Oxidation

To explore the possibility of coreaction of selective catalytic reduction with NH3 (NH3-SCR) and CO oxidation (CO-O), bimetallic doping catalysts of Mn and Cu were synthesized by a coprecipitation method, and XRD results showed coexisting Mn3O4 and CuO phases in this material. The evaluation results showed that Cu1Mn2 exhibits the highest activity among the investigated catalysts, with NO and CO conversions of up to 100% and 96.4% at 125 °C, respectively. The NO and CO conversions are 66.1% and 40.6% higher for the coordinate reaction than for the separate reaction for Cu1Mn2 at 125 °C. Cu1Mn2 has the highest number of acid sites and the strongest acidity, as well as the highest oxidation and reduction activities, among the investigated catalysts. Electronic transfer (Cu2+ + Mn3+ ↔ Mn4+ + Cu+) between copper and manganese cations in the Cu–Mn catalysts was validated. The feasibility of the coreaction of NH3-SCR and CO-O was verified in this study, and Cu doping was shown to be critical for the simultaneous reaction of NH3-SCR and CO-O.