【摘要】 用浸渍法制备了V2 O5/γ Al2 O3 和V2 O5/SiO2 负载型催化剂 ,应用H2 TPR、NH3 TPD、ESR等物理化学技术对其作了表征 ,比较了它们在 5 80℃时对异丁烷脱氢反应的催化性能。结果表明 ,V2 O5/γ Al2 O3 催化剂的脱氢活性较好 ,异丁烷转化率为 35 4 % ,这与γ Al2 O3 表面钒物种易还原 (还原温度为 5 4 2℃ )和分散状态好有关 ;而V2 O5/SiO2 催化剂显示出 96 %的高异丁烯选择性则与SiO2 载体酸性弱相符更多还原

【Abstract】 V 2O 5/γ-Al 2O 3 and V 2O 5/SiO 2 catalysts were prepared by the impregnation method and characte- rized by H 2-TPR, NH 3-TPD and ESR. Their catalytic activities were compared in the dehydrogenation of isobutane to isobutene at 580 ℃. The results show that V 2O 5/γ-Al 2O 3 exhibits higher activity than V 2O 5/SiO 2, resulting in 35.4% conversion rate, which is correlated with that vanadium oxide is better dispersed and more easily reduced on γ-Al 2O 3(reduction temperature 542 ℃) than on SiO 2, whereas V 2O 5/SiO 2 exhibits higher selectivity of isobutene higher than V 2O 5/γ-Al 2O 3 due to weaker acidity of the SiO 2 surface than that of the γ-Al 2O 3 surface.更多还原