摘要
采用水热法制得具有不同孔径的SBA-15材料;采用浸渍法制备了负载型铬基SBA-15催化剂,其结构和性能经XRD、低温氮气吸附脱附、氢气程序升温还原和X-射线光电子能谱表征。并研究了催化剂的CO_2氧化乙烷催化脱氢性能。结果表明:孔径对活性组分在SBA-15孔道内外的分布有影响,进而影响其催化性能。孔径为8.14 nm时,乙烷转化率25.8%,乙烯选择性81.0%。
A series of SBA-15 with different pore sizes were obtained by hydrothermal method. Several Cr-based SBA-15 catalysts were prepared by conventional impregnation method. The structures and properties were characterized by XRD, N_2 adsorption-desorption, H_2-TPR and XPS. The catalytic performances of Cr-based SBA-15 catalysts for ethane ODH in the presence of CO_(2 )were investigated. The results showed that pore size has an influence on the distribution of active components inside and outside the pores, and then affect the catalytic performances. When the pore size was 8.14 nm, the conversion of C_2H_6 was up to 25.8% and the selectivity of ethylene was 81.0%, respectively.
引文
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