Methanol plasma-catalytic degradation over CeO2 catalysts: effect of ceria morphology and reaction mechanism
作者单位：School of Environment and EnergySouth China University of Technology
会议名称：《第十一届全国环境催化与环境材料学术会议》
会议日期：2018年
学科分类：081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术]
关 键 词：Plasma-catalytic CeO2 Methanol Morphology Reaction pathways
摘 要：The effect of CeO morphology and reaction mechanism have been investigated in details on the plasma-catalytic oxidation of methanol. CeO with different morphologies(rod, particle, and cube) were prepared by a hydrothermal method and characterized by XRD, SEM, BET, Raman and XPS. The smallest particle size, the largest specific surface area and the most amount of oxygen vacancies could be achieved with CeO rod catalyst. Then all the catalysts were tested for methanol oxidation in plasma, and the results showed that CeO rod catalyst exhibited the highest removal efficiency, CO selectivity and ozone suppression. In-situ Raman spectroscopy experiments proved that the decomposition of ozone was related to the oxygen vacancy on the CeO [1]. CeO rod had the most surface oxygen vacancies, indicating that there were more active sites for ozone decomposition, and thus producing more reactive oxygen species could effectively oxidize methanol and increase CO selectivity. Compared with the oxidation of CO, the deep oxidation of methanol was the main reason why ozone improved CO selectivity in the plasma-catalytic system. Finally, the evolution of adsorbed intermediate species and some key steps of methanol oxidation were discussed based on the in-situ FTIR experiments. This work provided theoretical basis and guiding significance for improving the degradation of pollutants by optimizing the morphology of the catalyst in the plasma-catalyst system.