【摘要】 为控制稀燃汽油机NOx排放,在汽油机稀燃排气条件下,试验考察NiCu-ZSM5、CuCo-ZSM5等双金属分子筛催化剂的活性规律。结果表明:双金属交换分子筛催化剂的高活性温度窗口较宽,NOx最高转化率明显提高,并出现了几个不同的NOx转化率的峰值;空燃比为19时,NiCu-ZSM5催化剂在255℃条件下NOx的最大转化率为43.9%,空燃比为17时,CuCo-ZSM5在255℃条件下NOx的最大转化率达到41.6%;在催化反应过程中出现了CO浓度增加的阶段,表明此时HC是NOx的主要选择还原气体。更多还原

【Abstract】 Bimetallic zeolite catalysts such as NiCu-ZSM5 and CuCo-ZSM5 were investigated experimentally at practical exhaust of lean burn gasoline engine to remove NOx emission.The results show that the high activity temperature range is broad for bimetallic zeolite catalysts.The maximum conversion efficiency for NOx increases significantly and there are several peak values for NOx conversion efficiency.The maximal NOx conversion efficiency for NiCu-ZSM5 can get to 43.9% at 255 ℃ for air fuel ratio of 19.The maximal NOx conversion efficiency for CuCo-ZSM5 can get to 41.6% at 255 ℃ while the air fuel ratio is 17.The CO concentration may increase during the reaction process,which indicates that HC is the main selective reductive gas for NOx at the point.更多还原