介孔氧化铝负载钒催化剂上丙烷氧化脱氢制丙烯

 采用浸渍法制备了介孔氧化铝 (m-Al2O3) 负载钒催化剂 (V/m-Al2O3), 并考察了其催化丙烷氧化脱氢制丙烯反应活性. 通过 N2 吸附-脱附、透射电镜、X 射线粉末衍射、紫外-可见漫反射光谱、氢-程序升温还原和氨-程序升温脱附对催化剂进行了表征. 结果表明, 介孔氧化铝具有大比表面积、窄孔径分布和两维六方相结构, 在其上负载适量的 V 可实现 V 活性物种的高分散及催化剂的弱酸性, 从而有利于提高丙烷转化率和丙烯选择性. 与共合成法制备的含 V 介孔氧化铝 V/m-Al2O3(C) 和浸渍法制备的 V/?-Al2O3 相比, V/m-Al2O3 表现出更高的催化活性. 这与载体较弱的酸性和较大的比表面积以及 V 物种的高分散有关.

Oxidative Dehydrogenation of Propane to Propene over Mesoporous Alumina-Supported Vanadium Oxide Catalyst

Mesoporous alumina-supported vanadia catalyst (V/m-Al2O3) samples with different vanadium contents were prepared by the impregnation method and tested in the oxidative dehydrogenation of propane. The catalyst samples were characterized by N2 adsorption-desorption, transmission electron microscopy, X-ray powder diffraction, UV-Vis diffuse reflectance spectroscopy, H2 temperature-programmed reduction, and NH3 temperature-programmed desorption. The results showed that the support possessed 2D hexagonal mesostructure, large surface area, and narrow pore size distribution. Suitable loading of vanadia led to high dispersion of vanadium species and weak acidity of the catalyst, which improved the propane conversion and propene selectivity. V/m-Al2O3 also exhibited better catalytic performance than the vanadia-incorporated mesoporous alumina prepared by a co-synthesis method and ?-Al2O3-supported vanadia by an impregnation method.