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本文采用肼法测定了金属氧化物催化剂表面过剩氧的浓度，并考察了吡啶的氧化活性。催化剂的氧化活性与表面氧浓度成正比。氧化活性和表面氧浓度的顺序为：Ｃｕ－Ｏ／Ａｌ＿２Ｏ＿３＞Ｍｎ－Ｏ／Ａｌ＿２Ｏ＿３＞Ｃｒ－Ｏ／Ａｌ＿２Ｏ＿３＞Ｆｅ－Ｏ／Ａｌ＿２Ｏ＿３≥Ｃｏ－Ｏ／Ａｌ＿２Ｏ＿３＞Ｎｉ－Ｏ／Ａｌ＿２Ｏ＿３＞Ｃｅ－Ｏ／Ａｌ＿２Ｏ＿３．随着催化剂焙烧温度的提高，催化剂表面氧浓度和氧化活性均下降。Ｃｕ－Ｏ／ＳｉＯ＿２催化剂中添加ＣｅＯ＿２后，催化剂表面氧浓度和氧化活性均有明显提高，同时催化剂的热稳定性也明显增加。
In this paper, the concentration of excess oxygen on the surface of metal oxide catalyst was measured by hydrazine method and the oxidation activity of pyridine was investigated. The oxidation activity of the catalyst is proportional to the surface oxygen concentration. The order of the oxidation activity and surface oxygen concentration is: Cu-O / Al 2 O 3> Mn-O / Al 2 O 3> Cr-O / Al 2 O 3> Fe-O / Al 2 O 3> Co-O / Al 2 O 3> Ni-O / Al 2 O 3> Ce- Al 2 O 3. With the increase of catalyst calcination temperature, both the oxygen concentration and the oxidative activity on the catalyst surface decreased. The addition of CeO 2 to the Cu-O / SiO 2 catalyst significantly increased the oxygen concentration and the oxidation activity of the catalyst surface, while the thermal stability of the catalyst also increased significantly.