溶胶凝胶法和浸渍法制备的Cu/SiO_2催化剂的表征与性能

Characterization and catalytic behavior of Cu/SiO_2 prepared by sol-gel and impregnation methods

以CuCl2为铜源,采用溶胶凝胶法和浸渍法制备了SG-Cu/SiO2和IM-Cu/SiO2催化剂,用XRD、BET、IR、TPR等手段对催化剂进行了表征,考察了2种催化剂对NO+CO反应的催化性能.结果表明,不同方法制备的催化剂在孔容、比表面积和表面OH的分布上有很大差异,金属粒子在催化剂中的分散程度和存在状态也有所不同.在NO+CO反应中,SG-Cu/SiO2的催化性能高于IM-Cu/SiO2,在SG-Cu/SiO2催化剂中形成的难还原的铜物种对NO+CO的催化性能较好.

Using CuCl2 as precursor,we synthesized SG-Cu/SiO2 and IM-Cu/SiO2 through sol-gel method and impregnation method. They were tested by XRD, BET, IR, H2-TPR and their activity evaluation for NO＋CO action was also tested. The results showed that, because of the different preparing methods, the pore volume, surface area and surface OH distribution of the catalysts were very different, at the same time the dispersion of metal particle and the presence state are also different. In the NO ＋ CO reaction, SG-Cu/SiO2 catalyst had better catalytic activity than IM-Cu/SiO2 catalyst. Based on TPR result, the formation of copper species ,which are difficult reducted, was in favor of NO＋CO reaction in SG-Cu/SiO2 catalyst.