关键词: FeCrAl, 整体式催化剂, 甲苯催化燃烧, X射线粉末衍射, X光电子能谱

Abstract:

A series of Cu_xCo_1-x/Al₂O₃/FeCrAl (x=0-1) catalysts were prepared using an FeCrAl alloy as support, a boehmite primer sol as the first washcoat layer and copper as well as cobalt oxides as the active washcoat layer. The structure of the catalysts was characterized using X-ray powder diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and temperatureprogrammed reduction (TPR). Toluene was chosen as the model compound to evaluate the catalytic activity in a conventional fixed-bed quartz reactor. Results indicate that a Cu-Co-O solid solution phase was present when the content of Cu in the catalysts was low and a CuO phase was present when the content of Cu was high. Both Co²⁺ and Co³⁺ were present on the surface of the obtained monolithic catalysts while Cu²⁺ was the main Cu species. The addition of a proper amount of copper oxide improved the reducibility of the cobalt oxide, which enhanced the catalytic activity of the catalysts. All the obtained catalysts showed good activity for the catalytic combustion of toluene. The Cu_0.5Co_0.5/Al₂O₃/FeCrAl catalyst had the best catalytic activity, and toluene was totally oxidized at 374 °C over it.

Key words: FeCrAl, Monolithic catalyst, Toluene catalytic combustion, X-ray powder diffraction, X-ray photoelectron spectroscopy