HC-SCR reaction pathways on ion exchanged ZSM-5 catalysts
HC-SCR reaction pathways on ion exchanged ZSM-5 catalysts
复制标题
DOI：
10.1016/j.micromeso.2008.07.021
复制
发表时间：
2009
影响因子：
5.2
通讯作者：
Landong Li;N. Guan
中科院分区：
文献类型：
--
作者：
Landong Li;N. Guan
金属阳离子（金属=Cu、In和La）离子交换的ZSM-5沸石作为催化剂用于在过量氧下丙烷和丙烯选择性还原NO。采用原位DRIFTS方法研究了HC-SCR催化剂上的表面反应。对于C3 H8-SCR，吸附的硝酸盐物种（-NO3）被观察到作为主要的反应中间体，它们可以与气态丙烷反应生成N2，H2O和CO2。而C3 H6-SCR反应中，主要的反应中间产物为吸附态的胺（-NH 2），它们可以与NO或NO2反应生成最终产物。基于DRIFTS结果，提出了C3 H8-SCR和C3 H6-SCR在催化剂上的不同反应途径，并详细讨论了控制催化剂活性的主要因素。HC-SCR中NO-O2和HC-O2在催化剂上的竞争吸附是导致不同反应路径的主要原因。
Metal cation (metal=Cu, In and La) ion exchanged ZSM-5 zeolites as catalysts for the NO selective reduction by propane and propene in excess oxygen. The surface reactions of HC-SCR over catalysts were investigated through in situ DRIFTS method. For C3H8-SCR, adsorbed nitrate species (–NO3) were observed as main reaction intermediates and they could react with gaseous propane to produce N2, H2O and CO2. While for C3H6-SCR, adsorbed amine species (–NH2) were observed as main reaction intermediates and they could react with NO or NO2to produce the final products. The different reaction pathways for C3H8-SCR and C3H6-SCR over catalysts were proposed based on the DRIFTS results and the main factors controlling the activities of catalysts were discussed in details. The competing adsorption between NO–O2and HC–O2on the Brønsted acid sites of catalysts was responsible for the different reaction pathways in HC-SCR.