Ni-Mn bi-metal oxide catalysts for the low temperature SCR removal of NO with NH₃

详细信息    查看全文

• 作者：Yaping Wan ; Wenru Zhao ; Yu Tang ; Liang Li ; Huijun Wang ; Yunlong Cui ; Jinlou Gu ; Yongsheng Li ; Jianlin Shi
• 关键词：Low temperature NO-SCR ; Nickel and manganese mixed oxides ; Surface Mn4+ active species ; Lewis acid sites
• 刊名：Applied Catalysis B: Environmental
• 出版年：27 April, 2014
• 年：2014
• 卷：148-149
• 期：Complete
• 页码：114-122
• 全文大小：1158 K

文摘

A series of nickel-manganese bi-metal oxide catalysts of different Ni/Mn ratios were prepared by a co-precipitation method for the low temperature selective catalytic reduction (SCR) of NO with NH₃ in the presence of excess O₂. The NO conversion over different catalysts decreased in the following sequence of Ni(0.4)-MnO_x > MnO_x >> Ni(1)-MnO_x > Ni(2.5)-MnO_x > NiO_x. The Ni(0.4)-MnO_x catalyst showed the highest catalytic activity, 85% of NO conversion at 95 掳C and 100% from 120 to 240 掳C, among the catalysts investigated. The TPR, XPS, NH₃-TPD and in situ FTIR results revealed that Mn⁴⁺ was the main active species for SCR reaction and the addition of nickel species enhanced the surface concentration and acidity of Lewis acid sites. A possible synergetic catalytic effect was proposed for the low temperature SCR reaction through the electron transfer between Mn and Ni ions.