V_2O_5/NiO catalysts were prepared by a solid phase ball milling method using NiO and V_2O_5 calcined at different temperatures as precursors.The influence of precursor calcination temperature on the catalytic performance of the V_2O_5/NiO catalysts for oxidative dehydro-genation of propane to propene was investigated. The catalysts were characterized by X-ray diffraction, nitrogen physisorption, inductively-coupled plasma atomic emission spectroscopy, transmission electron microscopy, hydrogen temperature-programmed reduction, and X-ray photoelectron spectroscopy. The results showed that the prerared V_2O_5/NiO catalysts exhibited better catalytic performance and the catalyst obtained from the precursor calcined at 400℃ exhibited high selectivity for propene, which is due to their more noncomplete reduction oxygen species Od-existed on the surface of V_2O_5/NiO. At 475℃, 20.1% of C_3H_6 conversion and 71.2% of C_3H_6 selectivity were observed over V_2O_5/NiO catalyst when the precursors were calcined at 400℃.%以不同温度焙烧制备的NiO和V_2O_5为前驱物,采用固相球磨法制备了V_2O_5/NiO催化剂,考察了前驱物的焙烧温度对该催化剂丙烷氧化脱氢制丙烯反应性能的影响,并采用x射线衍射、N_2物理吸附、电感耦合等离子体原子发射光谱、透射电子显微镜、H_2程序升温还原和x射线光电子能谱等对催化剂进行了表征.结果表明,固相球磨法制备的V_2O_5/NiO催化剂表现出较好的丙烷氧化脱氢制丙烯催化性能,当以400℃焙烧的氧化物为前驱体时,V_2O_5/NiO催化剂表面含有较多的未完全还原氧物种O~(δ-),因而表现出了较高的丙烯选择性.在475℃反应时,丙烷转化率可达20.1%,丙烯选择性达到71.2%.
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