C_3H_6和NO在Cu-Al-MCM-41催化剂上的反应和吸附行为

Adsorption and Reaction of Propylene and Nitrogen Oxide on Cu\|Al\|MCM\|41

利用 XRD、NMR、N2 吸附等温线、TPD、原位红外 ( in situ FTIR)和程序升温反应技术等手段考察了 Cu- Al- MCM- 41的结构特征、化学吸附性能和催化 NO选择性还原的反应活性。经 Cu离子交换的 Al- MCM- 41并未改变载体的结构特征 ,仍保持长程有序的中孔结构。C3H6和 NO在Cu- Al- MCM- 41上发生竞争吸附。C3H6在反应中起双重作用 :一方面 ,提供 NO选择性还原的还原物种 ;另一方面 ,由于其在催化剂上的强吸附而阻抑了

Al MCM 41 and Cu Al MCM 41 were prepared by a modified hydrothermal method. The characterization using XRD, NMR and N 2 isothermal adsorption revealed that the structure of Al MCM 41 remained unchanged after the exchange of copper ion. The chemisorptive properties of Cu Al MCM 41 as well as its catalytic activity for the reaction of NO by C 3H 6 were investigated by TPD, in situ FTIR and temperature program reaction techniques. It was found that both propylene and NO could adsorb on the copper sites but the adsorption of propylene was more competitive. Thus, C 3H 6 not only played the role as reductant but also caused the inhibition of the adsorption of NO, which affected the conversion efficiency in turn.