以XRD、H2-TPR等方法表征Mo掺杂V/TiO2新型催化剂，并详细考察了催化剂组成、反应温度、空速等对Mo掺杂V/TiO2催化2-甲基吡啶氧化合成2-吡啶甲醛的影响。实验研究结果表明，Mo的掺杂提高了催化剂的还原能力和催化活性。低反应温度和高空速可以提高对2-吡啶甲醛的选择性。钒和钼的最佳比率为2.9：1，催化剂的最佳负载量为7%。最佳反应条件下(催化剂焙烧温度600℃，反应温度290℃，10%2-甲基吡啶水溶液的流速为0.2 mL×min-1，氧气的流速为0.1 L×min-1，空速为3083 h-1)，2-甲基吡啶的转化率为70.2%，2-吡啶甲醛的选择性为88.3%，与文献报道的未使用Mo 掺杂的催化剂所得的结果(转化率14%，选择性93%)相比，在选择性相差不大的情况下，转化率大幅度提高。%The gas-phase oxidation of 2-picoline to 2-pyridylaldehyde over Mo-modified V/TiO2 catalysts was studied. The newly prepared V-Mo/TiO2 catalysts were characterized by XRD and H2-TPR. The effects of experimental parameters, such as the catalyst composition, reaction temperature and space velocity, on the reaction were investigated in detail. The results show that the addition of Mo to V/TiO2 greatly increases the reducibility and thus the catalytic activity of the catalysts. Low reaction temperature and high space velocity lead to high selectivity to 2-pyridylaldehyde. The optimal V/Mo molar ratio and loading amount of the catalyst are 2.9:1 and 7%respectively. Under optimal conditions (calcination temperature 600℃, reaction temperature 290℃, flow rate 0.2 mL×min-1 of 10%2-picoline solution, oxygen flow rate 0.1 L×min-1, contact time 1.16 s), the V-Mo/TiO2 catalysts give 70.2% conversion of 2-picoline which is much higher than that of the V/TiO2 catalysts reported in the literature (which is 14%with 93%selectivity to 2-pyridylaldehyde).
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