Design of bimetallic catalyst with dual-functional Cu-Ce sites for synergistic NOX and toluene abatement

Nitrogen oxides (NOx) and volatile organic compounds (VOCs) coexist in the flue gases from coal-fired power plants and iron/steel smelting industry. In this study, a dual-site catalyst, composed of Cu-Ce-Ti mixed oxide, was screened for the synergistic elimination of NOx and VOCs. The catalyst showed a synergistic removal efficiency above 95% for both C7H8 and NO at 250 °C, and sustain the NOx and VOCs removal efficiencies above 90% even in the presence of 5 vol% H2O and 500 ppm SO2 at 300 °C. Mechanistic studies revealed that the Cu and Ce sites play individual roles in toluene oxidation and NOx reduction, respectively. The primarily occurred SCR reaction facilitated electron exchange through the redox cycling between Ce4+/Ce3+ and Cu2+/Cu+ pairs, resulting in a high abundance of Cu2+ sites being highly active in toluene oxidation. This study could provide new strategy for high-performance catalysts toward synergistic NOx and VOCs abatement.