摘要
采用浸渍法将铜(Cu)负载在ZSM-5分子筛上,制备了一系列不同Cu含量的Cu/ZSM-5分子筛催化剂。对ZSM-5及Cu/ZSM-5分子筛催化剂的氨选择性催化还原一氧化氮(NO)性能进行评价,并对Cu/ZSM-5分子筛催化剂进行表征分析。结果表明,Cu含量变化对Cu/ZSM-5分子筛催化剂的氨选择性催化还原反应(NH3-SCR)活性影响较大,Cu含量为0.75%(wt,质量分数)制得的Cu/ZSM-5具有最佳的中低温活性,在190℃条件下对NO的转化率为91%。
Cu/ZSM-5 catalysts with different copper loadings were prepared by impregnation method.The performances of ZSM-5 and Cu/ZSM-5 catalysts in selective catalytic reduction of nitric oxide(NO)with ammonia(NH3)were investigated and the physicochemical properties of samples were characterized by XRD,XPS,BET,H2-TPR and NH3-TPD.The change of copper content was important to the activity of Cu/ZSM-5 catalysts for selective catalytic reduction with ammonia(NH3-SCR).The sample with copper content of 0.75 wt% obtained the best activity at medium and low temperatures,its conversion of NO reached 91% at 190℃.
引文
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