考察了银负载量及反应气预处理对银催化剂上CO选择氧化反应的影响. 结果表明,O2转化率、CO的转化率及选择性都随着银负载量的增加而升高,CO氧化的选择性随着温度的降低而升高,低温下的选择性可达70%～80%. CO-TPR谱显示,产物CO2脱附量及脱附温度的次序与CO选择氧化活性有一致的对应关系. 当反应气处理温度为300 ℃时,催化剂上CO氧化活性最高; 随着反应气处理温度的继续升高,CO氧化活性及选择性反而降低. 金属银的粒子尺寸随着银负载量的增加而增大; 高温下反应气处理后,金属银粒子的尺寸明显减小. 催化剂上CO氧化活性及选择性与银粒子的大小及催化剂的表面结构有关.
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