| Recently, exhaust pollution of motor vehicle which has been incriminated as one of the causes of air pollution in cities has become a social problem, causing wide public concern. A conventional three-way catalyst, whose active component is Pt, Pd and Rh, has shown good catalytic performance in practical use. But there are many problems, such as expensive price and high cost, producing secondary pollution, and so on. So many reaearchers are studying on new three-way catalyst with non-noble metal as the active component.Under this background, a series of supported CuO catalysts and its aged samples using CeO2,Ce0.6Zr0.4O2 and CeO2/γ-Al2O3 as the supports were prepared by impregnation method, and their catalytic activity for simultaneous removal of CO,C3H6 and NO were investigated. The structure and redox property of the catalysts were characterized by XRD and H2-TPR, the results are as follows:1. Copper-based catalysts had good TWC performance, especially when it was supported on CeO2/γ-Al2O3.2. The comparison of catalytic behaviors of CuO/CeO2/γ-Al2O3 and Pd/CeO2/γ-Al2O3 catalysts suggested that CuO/CeO2/γ-Al2O3 has similar catalytic performance with that of noble catalyst, and even has better activity at lower temperature.The light-off temperature of CO, HC and NOx were 130℃,250℃and 250℃over CuO/CeO2/γ-Al2O3 catalyst, and the three pollutents were completely converted at 350℃.3. Compared with the fresh sample,the aged sample showed enhanced light-off temperatures. The light-off temperature of CO, HC and NOx were increased from 130℃,250℃and 250℃to 200℃,270℃and 270℃,respectively. The results showed that CuO/CeO2/γ-Al2O3 catalyst still has good catalytic performance, even after calcination at 900℃for 4h.4. The results of XRD and H2-TPR suggested that CuO can be well dispersed over both fresh and aged CuO/CeO2/γ-Al2O3 catalyst, reflecting in little change in redox property of the fresh and aged sample, which might be the possible reasons for its higher catalytic activity.
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