SO2对Ag/Al2O3催化剂上CH3OH还原NO性能的影响

用溶胶-凝胶混合法制备了Ag负载量为5%的Ag/A1₂O₃催化剂.研究了富氧条件下,SO₂对CH₃OH在催化剂上还原NO性能的影响.结果表明,反应气不含SO₂和H₂O时,NO还原活性温度较低,有显著量N₂O生成,这被归因为反应过程中,部分氧化态Ag被还原为金属Ag.添加SO₂或同时添加SO₂和H₂

Effects of SO2 on NO Reduction with Methanol over Ag/Al2O3 Catalyst

Ag/Al₂O₃ catalyst with 5% Ag loading was prepared by the single step sol gel mixture method and the effects of adding SO₂ to reaction feed on NO reduction by CH₃OH over the catalyst was investigated in the presence of oxygen. The results showed that in the absence of SO₂ and H₂O the catalyst displayed lower activity temperature and higher N₂O selectivity, which was attributed to the partial reduction of oxidized Ag into metallic Ag under reaction conditions. Selective catalytic reduction activity was not decreased but significantly increased,N₂O formation was suppressed and most effective NO reduction temperature shifted to higher temperature by pre sulfated Ag/Al₂O₃ or addition of SO₂ to reaction mixture. XPS analysis showed that the sulfate like species were formed by the effect of SO₂.