采用浸渍法制备载体负载铜氧化物催化剂。通过XRD、TG-MS、XPS、NO-TPD、NH3-TPD和H2-TPR等手段对催化剂进行表征,考察了有氧条件下载体对催化剂NH3-SCR低温脱硝性能的影响。结果表明,铜物种在载体上以CuO和Cu2O形式共存,载体影响铜物种的分散性和氧化态,影响催化剂酸性、氧化还原性和对反应物的吸脱附能力。Cu/HZSM-5催化剂,铜物种分散度高,氧化还原性能好,具有适宜的酸性和酸量,对反应物有良好的吸附-脱附性能,在NH3-SCR脱硝反应中具有较好的催化活性,反应温度低,T50和T90分别为137和165℃,活性窗口温度宽,NO转化率高于90%的温度为165-358℃。
The catalysts of supported copper oxide were prepared by impregnation method, which were characterized by XRD,TG-MS,XPS,NO-TPD,NH3-TPD and H2-TPR and the effect of carrier on the performance of catalysts for the selective catalytic reduction of NO with NH3 at low-temperature in the presence of oxygen was investigated. The results show that the copper species exist in the form of CuO and Cu2 O on carriers. The dispersion and oxidation state of copper species,the acidity and redox ability of the catalysts and the performance of adsorption/desorption are affected by the carriers. The Cu/HZSM-5 catalyst with highly dispersed copper speicies has excellent redox properties,suitable acidity and acid capacity,and good adsorption/desorption performance for reactants,which show s a good catalytic activity in the NH3-SCR denitrification reaction. The reaction temperature is low er,T50 and T90is 137 and 165 ℃,respectively,and the active window temperature is wide. The temperature range for the NO conversion of over 90% is 165-358 ℃.