Trade-Off Between Redox Ability And Reactive Behaviors For Acrylonitrile Selective Catalytic Combustion Over The Cu-Ce-Based Uzm-9 Catalysts

In the study, the performance of acrylonitrile selective catalytic combustion over a series of Cu-Ce-based UZM-9 catalysts were evaluated, and the interaction between Ce (Ce) and Cu were systematically characterized by Ar adsorption-desorption, XRD, XPS, UV-vis, EPR and H-TPR. The chemical state of Ce and Cu species were associated strongly with the loading amount of Ce, and there was a critical Ce content (about 15 wt%). For Cu-6.5-Ce-15 %, CeO could promote the shift of partial isolated Cu to the outer surface of the crystals and weaken the interaction between Cu and the zeolite. Then, the reducibility of Cu species could be significantly improved, which were the main active sites of the reaction. Comparing with Cu-6.5, the AN conversion activity and CO selectivity of Cu-6.5-Ce-15% were significantly improved and the excellent N selectivity was still maintained. Finally, in situ DRIFTS revealed that the reaction mainly followed hydrolysis mechanism over Cu-6.5-Ce-15%.