| 不同硅铝比Fe-ZSM-5催化剂对氧化亚氮催化分解性能的研究 |
| 摘要点击 1794 全文点击 1301 投稿时间：2013-04-22 修订日期：2013-06-21 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 ZSM-5 铁修饰 硅铝比 氧化亚氮 催化分解 |
| 英文关键词 ZSM-5 iron-modified Si/Al ratio nitrous oxide catalytic decomposition |
|
| 中文摘要 |
| 以不同硅铝比的H-ZSM-5分子筛为载体，采用离子交换法和化学气相沉积法制备Fe-ZSM-5催化剂，并用XRD、BET、TEM、UV-vis和NH3-TPD等表征手段对催化剂进行分析，研究催化剂中铁的存在状态. 结果表明，分子筛的硅铝比影响铁在分子筛中的分布形态，化学气相沉积法和热离子交换法制得硅铝比为25的Fe-ZSM-5-25分子筛催化剂上均匀地分布着粒径为8 nm左右的纳米氧化铁颗粒，并且Fe-ZSM-5-25分子筛催化剂比Fe-ZSM-5-300更容易形成Fex3+Oy团簇. 制得的Fe-ZSM-5分子筛催化剂催化分解氧化亚氮（N2O），结果表明，相同的制备方法，硅铝比小的Fe-ZSM-5-25催化剂对N2O分解活性更好；相同硅铝比的Fe-ZSM-5催化剂，采用化学气相沉积法制得的对N2O分解活性最好. 另外，O2的存在对Fe-ZSM-5上N2O催化分解活性有抑制作用，而NO对N2O催化分解活性展示了一定的正效应. 最后，经过100 h的连续反应，Fe-ZSM-5催化剂依然能够保持催化活性. |
| 英文摘要 |
| The Fe-ZSM-5 catalysts were prepared with H-ZSM-5 of different Si/Al ratios by wet ion exchange and chemical vapor deposition. Then the catalysts were investigated by XRD, BET, TEM, UV-vis and NH3-TPD technologies to analyze the iron states in Fe-ZSM-5 zeolites. The results showed that after H-ZSM-5 zeolites were prepared by chemical vapor deposition and heating wet ion exchange, the nano Fe2O3 particles were uniformly dispersed with the sizes of 8 nm in the Fe-ZSM-5-25 (Si/Al-25). Moreover, there were more oligonuclear Fex3+Oy clusters in the Fe-ZSM-5-25 catalysts than in Fe-ZSM-5-300 (Si/Al-300). The results of catalytic performance on N2O decomposition showed that Fe-ZSM-5-25 catalysts had higher catalytic activities than Fe-ZSM-5-300 catalysts. The Fe-ZSM-5 catalysts prepared by chemical vapor deposition achieved the best catalytic activity in N2O decomposition among the catalysts prepared by the three methods. Moreover, the presence of O2 only slightly reduced N2O conversion, while NO promoted the N2O decomposition. Finally, after reaction for more than 100 h, Fe-ZSM-5 catalyst showed no obvious deactivation under simulated emission conditions. |
