Effects of Synergy of Copper Oxide and Cerium Oxide on DeNO_x Activity of CuCeMgAl(O) Catalyst

Ce-Cu-containing catalyst (CeCuMgAl(O)) was prepared by coprecipitation whose catalytic activity for NO + CO in the presence of oxygen was examined and compared with the catalyst free of cerium. The effect of H₂O on the catalytic activity was also investigated. The results show that for NO + CO reaction in the presence of oxygen, the activity-temperature-window of CeCuMgAl(O) shifts to lower temperature than that of CuMgAl(O). The presence of H₂O gives rise to the significant changes of catalytic activity of these two catalysts in low temperature region: great reducing for CuMgAl (O) and intensive increase for CuCeMgAl(O) whereas no obvious effect in high temperature region. The synergy between Cu-Ce oxides and thus much more Cu⁺ exist in the CeCuMgAl(O) than CuMgAl(O) are responsible for these differences.