负载型铜催化剂的三效催化性能及应用

采用等体积浸渍法制备了以CeO2、Al2O3以及CeO2/Al2O3为载体的负载型CuO催化剂及其老化样品,采用XRD和H2-TPR等技术对老化前后催化剂的结构和氧化还原性能进行了表征。结果显示,对于老化前后的CuO/CeO2/Al2O3催化剂,CuO均能够很好地分散在载体上,即CeO2/Al2O3具有较好的抗烧结能力。考察了不同载体、CeO2和CuO负载质量分数对CuO/CeO2/Al2O3样品三效催化性能的影响,并将制得的CuO/CeO2/Al2O3催化剂与贵金属三效催化剂Pd/CeO2/Al2O3相比较,考察了高温焙烧之后的CuO/CeO2/Al2O3老化样品对CO、C3H6和NO的三效催化性能。结果表明,以10%CeO2/Al2O3为载体,CuO负载质量分数为7%的CuO/CeO2/Al2O3催化剂对汽车尾气脱除催化反应具有较高的催化活性;与Pd/CeO2/Al2O3比较,CuO/CeO2/Al2O3具有更好的低温活性,CO、HC和NOx的起燃温度分别为130℃、250℃和250℃,在350℃三种原料气的转化率均达到90%;老化实验表明,CuO/CeO2/Al2O3具有较好的抗老化性能。

Three-way catalytic behaviors and application of supported copper catalysts

A series of supported CuO catalysts and its aged samples, using CeO2, Al2O3 and CeO2/ Al2O3 with different loading of CeO2 as the supports, were prepared by impregnation method. Characterization of their structure and redox properties by XRD and H：TPR showed that CuO were well dispersed over CeO2/Al2O3 support both in fresh and aged CuO/CeO2/Al2O3 catalysts, indicating that the catalysts had good resistance to sintering. Effects of different supports and loadings of CeO2 and CuO were investigated and comparison was made between CuO/CeO2/Al2O3 and Pd/CeO2/Al2O3. The three-way catalytic activity of aged CuO/CeO2/Al2O3 catalyst calcined at high temperature was tested. The results showed that CuO/CeO2/Al2O3 catalyst with CuO loadings of 7% and supported on 10% CeO2/Al2O3 exhibited superior three-way catalytic activity, with superior activity to that of Pd/CeO2/Al2O3 especially at lower temperature and light-off temperature for CO, HC and NOx of 130 ℃ ,250 ℃ and 250 ℃, respectively, and conversion of 90% for the three pollutants at 350 ℃. CuO/CeO/Al2O3 also exhibited good resistance to aging.