Enhancing low-temperature ethanol-selective catalytic reduction over Ag/TiO2-cordierite catalysts via cerium addition

Abstract

The purpose of this study is to investigate the NOx reduction activity of Ag/TiO2-Cordierite catalysts enhanced with cerium (Ce) under varying operational temperatures and engine loads. The aim is to improve the low-temperature activity of the catalyst in an ethanol-selective catalytic reduction system using real exhaust gases. During the catalyst production process, Ag and Ce were used as active components, TiO2 as the secondary support material, and cordierite as the primary carrier structure material. Catalysts with 1 wt%, 3 wt%, and 5 wt% Ce-doped Ag/TiO2/Cordierite were synthesized using the washcoating method and characterized through X-Ray Diffraction, Brunauer–Emmett–Teller analysis, and Scanning Electron Microscopy (SEM). Performance test results demonstrated that the NOx conversion rates of the Ce-doped catalysts exceeded 90% at 300 °C and a space velocity of 40,000 h⁻1. Notably, the highest NOx conversion rate of 92.48% was achieved with the 5% Ce-Ag/TiO2/Cordierite catalyst. These findings indicate that the incorporation of Ce into Ag/TiO2/Cordierite catalysts significantly enhances NOx conversion activity at low temperatures in the ethanol-SCR system.