Synthesis and catalytic performance of Cu1Mn0.5Ti0.5Ox mixed oxide as low-temperature NH3-SCR catalyst with enhanced SO2 resistance

A new type of low-temperature NH3-SCR catalyst with a chemical composition of CuwMnyTi1-yOx was prepared from layered double hydroxides precursors for the first time. The purpose of this novel design is to improve the De-NOx efficiency and SO2 resistance of Mn-based catalysts. The Cu1Mn0.5Ti0.5Ox catalyst achieved a NOx conversion as high as 90% at 200 degrees C, which is much higher than that of the control catalysts Cu-Mn/TiO2 (86.1%) and Mn/TiO2 (80.7%). The properties of catalysts were characterized in detail using a series of physicochemical techniques including XRD, BET, FOR, SEM, TEM, H-2-TPR, NH3-TPD, TGA, and XPS analyses. The excellent catalytic performance of Cu1Mn0.5Ti0.5Ox catalyst can be associated with its higher specific surface area and surface acidity, and more active MnO2 and CuO species. Besides, when copper oxide is introduced, the catalysts showed significant resistance to 100 ppm SO2 and 5% H2O. Finally, the poisoning mechanism and the regenerability of Cu1Mn0.5Ti0.5Ox catalyst was proposed. In short, the newly designed Cu1Mn0.5Ti0.5Ox catalyst was found to have higher catalytic activity and excellent SO2 and H2O resistance compared to the control catalysts of Cu-Mn/TiO2 and Mn/TiO2.