摘要
研究了稀燃条件下低温等离子体(NTP)协同丙烯在Ag/Al2O3催化剂上选择性催化还原NOx反应,通过原位漫反射傅里叶变换红外光谱(DRIFTS)对NTP协同前后反应气中NO和C3H6的吸附以及丙烯选择性催化还原反应进行了表征.结果表明,丙烯的活化是Ag/Al2O3上选择性催化还原反应的关键步骤.NTP活化反应气体后,Ag/Al2O3表面-NCO、R-NO2和有机酸根等物种的数量大幅度增加,并且其催化还原NOx的低温(<350℃)活性也显著提高.在NTP协同前后,选择性催化还原过程可能存在两条反应路径,较低温度下主要是-NCO生成N2,而较高温度下则是-CN向N2转化.
The non-thermal plasma （NTP）-assisted selective catalytic reduction （SCR） of NO, by propene over the Ag/Al2O3 catalyst was investigated. In situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） studies were carried out on the NO and C3H6 adsorption and SCR reactions over Ag/Al2O3 with or without NTP pretreatment. The results showed that the low-temperature activity of C3H6-SCR was remarkably enhanced with the assistance of NTP in the presence of excess oxygen. The activation of propene was the key step in C3H6-SCR over Ag/Al2O3. After the application of NTP, the amount of -NCO, R-NO2 and organic acid species over Ag/Al2O3 significantly increased, which caused a high catalytic activity at low temperatures （〈350℃ ）. Two reaction paths were proposed in both SCR and NTP-SCR. At low reaction temperatures, -NCO was the key intermediate to generate N2, while it was -CN at high reaction temperatures.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2005年第11期951-955,共5页
基金
国家高技术研究发展计划(863计划)项目(2004AA649150)
国家自然科学基金重点项目(20437010)资助
关键词
低温等离子体
银
氧化铝
选择性催化还原
稀燃
氮氧化物
原位漫反射傅里叶变换红外光谱
non-thermal plasma, silver, alumina, selective catalytic reduction, lean burn, nitrogen oxide, in situ diffuse reflectance infrared Fourier transform spectroscopy
