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采用ＭｏＯ３／ＳｉＯ２和ＮＨ３程序升温反应的方法合成了一系列不同Ｍｏ含量的Ｍｏ２Ｎ／ＳｉＯ２催化剂，并采用ＸＲＤ、ＢＥＴ、ＸＰＳ、ＴＰＲ、Ｈ２ＴＰＤ和ＩＲ等手段，结合中压下吡啶加氢脱氮反应，研究了它们的表面性质和反应性能．发现Ｍｏ２Ｎ／ＳｉＯ２催化剂在反应性能和吸氢性质等方面类似于非负载的氮化钼．氮化前后，低Ｍｏ担载量催化剂的比表面积降低不大，在高Ｍｏ担载量下，由于氮化态的Ｍｏ／ＳｉＯ２催化剂上出现了粒径更小的晶相γＭｏ２Ｎ，而使其比表面积比前身态的增加．在钝化态的Ｍｏ２Ｎ／ＳｉＯ２表面，有Ｍｏ６＋、Ｍｏ４＋和Ｍｏδ＋（０＜δ＜２）三种价态的Ｍｏ存在，其中高价钼以氮氧化物或无定形的ＭｏＯ２的形式存在，它们可在高温被还原．ＮＯ和吡啶吸附的红外结果表明，在Ｍｏ２Ｎ／ＳｉＯ２催化剂上有配位不饱和的Ｍｏ中心和Ｌ酸中心存在，它们是吡啶加氢脱氮的吸氢活性中心和脱氮活性中心．
A series of Mo2N / SiO2 catalysts with different Mo content were synthesized by the temperature-programmed reaction of MoO3 / SiO2 and NH3. The catalysts were characterized by XRD, BET, XPS, TPR, H2TPD and IR, Nitrogen reaction, their surface properties and reactivity were studied. The Mo2N / SiO2 catalyst was found to be similar to unloaded molybdenum nitride in terms of reactivity and hydrogen absorption properties. Before and after nitriding, the specific surface area of the catalysts with low Mo loading did not decrease significantly. Under the high Mo loading, due to the smaller grain size γMo2N on the nitrided Mo / SiO2 catalyst, The specific surface area than the previous state of increase. In the passivated Mo2N / SiO2 surface, Mo is present in three valence states of Mo6 +, Mo4 + and Moδ + (0 <δ <2), of which molybdenum is present in the form of oxynitride or amorphous MoO2, High temperature is reduced. The infrared results of NO and pyridine adsorption show that Mo centers and L acid centers exist on the Mo2N / SiO2 catalysts, which are the sites for hydrogenation of pyridine hydrodenitrogenation and the active sites for denitrification.