助剂Ag对Cr/γ-Al_2O_3氧化物催化剂CO氧化性能的影响

EFFECT OF PROMOTER Ag ON PERFORMANCE OF Cr/γ Al 2O 3CATALYST FOR CO OXIDATINM

本文用硝酸盐水溶液等量浸渍法制备了一系列Ｃｒ－Ａｇ／γＡｌ２Ｏ３双金属及单金属氧化物催化剂，测定了ＣＯ氧化转化率。用ＢＥＴ、ＸＲＤ、ＴＰＲ、ＴＰＤＭＳ技术研究了助剂Ａｇ对Ｃｒ／γ－Ａｌ２Ｏ３催化剂ＣＯ氧化反应的作用。结果表明，少量Ａｇ的添加能明显提高Ｃｒ／γＡｌ２Ｏ３催化剂对ＣＯ的氧化活性，且随Ａｇ添加量的增加而增强。ＴＰＲ和ＴＰＤＭＳ实验发现，Ａｇ的添加使催化剂的还原性能和表面氧性质发生明显变化，催化剂表面氧活动性增强。催化剂对ＣＯ的氧化活性与催化剂表面氧的活动性有很好的对应关系。

Aseries of γ Al 2 O 3 supported Cr Ag bimetallic and mono metallic cata lysts were prepared by wet impregnation mehtod The oxidation activity of CO was deter mined in a flow reactor system The effect of promoter Ag was studied by BET,XRD,TPR and TPD MS The result showed that the activity of Cr/γ Al 2 O 3 catalyst for CO oxidationwas evidently enhanced because of the addition of Ag,and increased with the content of Ag The promoter Ag could obviously change the reducibility and surface oxygen property of thecatalyst,and promote the oxygenous activity of catalyst CO oxidation activity of the cata lysts was correlated to their surface oxygen property