CO Oxidation On Mesoporous SBA-15 Supported CuO-CeO₂ Catalyst Prepared By Surfactant-assisted Impregnation Method

A series of mesoporous SB A-15 supported CuO-CeO2 catalysts were prepared by the surfactant-assisted impregnation method. The prepared CuO-CeO2/SBA-15 catalysts were studied by XRD, adsorption-desorption of N2 at -196 ?, SEM, TEM, Raman spectroscopy,XPS, H2-TPR, CO-TPD techniques, and low-temperature CO oxidation testing, Moreover, the relationship between catalytic activity and physicochemical properties was investigated. In this article, the four experiments involved are as follows:(1) Mesoporous SBA-15 supported CuO-CeO2 catalysts were prepared by the surfactant-assisted impregnation method with PEG 200 as the surfactant, and the effect of the amount of PEG 200 were studied. The results indicate that the catalyst prepared with the PEG 200 content of VPEG:VH2O=1 has the best catalytic performance. The enhanced catalytic performance can be ascribed to the more finely dispersed Cu species on ceria and larger amount of active sites.(2) Mesoporous SBA-15 supported CuO-CeO2 catalysts were prepared by the surfactant-assisted impregnation method with PEG 200 as the surfactant, and the effects of calcination temperature (400, 500, 600, 700 ?) of catalysts were investigated. The result shows that the catalytic activity of catalysts is best with the calcination temperature of 500 ?.It is found that low calcination temperature is not conducive to the dispersion of copper species, while high calcination temperature leads to the agglomerate of the particles of the catalyst, which can weaken the interaction between copper and cerium and consequently reduce the activity of the catalyst.(3) CuO-CeO2/SBA-15 catalysts were prepared by the surfactant-assisted impregnation method with PEG of different molecular weight (PEG 200, 400, 600) as the surfactant, and the influence of the molecular weight of PEG on catalytic activity was studied. The results show that the molecular weight of PEG has a distinct effect on the particle size of active component of the catalysts. The catalysts prepared with PEG 200 have smaller particles,which led to the better catalytic activity.(4) CuO-CeO2/SBA-15 catalysts were prepared surfactant-assisted impregnation method using different types of surfactant, and the effect of the types of the surfactant on catalyst activity was investigated. The results show that all the surfactants used here can improve the catalytic activity of the catalyst, but the catalyst prepared with anionic surfactant (sodium citrate) has better activity. Furthermore, it is found that the anionic surfactant can improve the dispersion of catalyst, and enhance the interaction between copper and cerium, which can improve the activity of catalyst.