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用浸渍法制备了组成为Ｖ２Ｏ５∶Ｐ２Ｏ５∶ＳｉＯ２ ＝２０∶ｘ∶１００（ｘ ＝０ ～６０，质量比）的ＶＰＯ／ＳｉＯ２ 催化剂，用ＴＰＲ，ＩＲ和ＴＰＤ法测定了苯和氧在催化剂表面的吸附，在无气相氧和吸附氧存在的条件下用连续ＴＰＤ 方法测定了苯化学吸附与催化剂表面活性端基氧之间的关系． 发现ＶＰＯ／ＳｉＯ２ 催化剂对苯的吸附至少有四种吸附中心，但有两种吸附中心是不具有催化活性的，一种对应于苯的物理吸附，而另一种则被ＣＯ２ 所占据．ＶＰＯ／ＳｉＯ２ 催化剂表面上氧的吸附随催化剂中Ｐ２Ｏ５ 含量的增加而增加，而苯的化学吸附随催化剂表面活性端基氧的增加而增加．
VPO / SiO2 catalysts with the composition of V2O5:P2O5:SiO2 = 20: x: 100 (x = 0 ~ 60, mass ratio) were prepared by impregnation method. The contents of benzene and oxygen The adsorption of benzene on the catalyst surface, in the absence of gas-phase oxygen and adsorbed oxygen in the presence of continuous TPD method was measured benzene chemical adsorption and catalyst surface active terminal oxygen. Found V P O / SiO2 catalyst for benzene adsorption at least four adsorption centers, but two adsorption centers are not catalytically active, one corresponding to the physical adsorption of benzene, while the other was CO2 occupy. The adsorption of oxygen on the surface of VPOSiO2 catalyst increases with the increase of P2O5 content in the catalyst, while the chemisorption of benzene increases with the increase of the surface active oxygen of the catalyst.