CoH-FBZ催化剂表征及选择催化CH_4还原NO  

Characterization of CoH-FBZ and selective catalytic reduction of NO by CH_4

作　　者：张金桥[1] 刘于英[1] 樊卫斌[1] 李瑞丰[1] 

机构地区：[1]教育部煤科学与技术重点实验室太原理工大学精细化工研究所,山西太原030024

出　　处：《化工学报》2006年第9期2105-2110,共6页CIESC Journal

基　　金：国家自然科学基金项目(20206020).~~

摘　　要：一种具有FAU和BEA双微孔拓扑结构的分子筛催化剂CoH-FBZ用于富氧条件下CH4催化还原NO(CH4-SCR),应用XRD、FT-IR、DRS-UV-Vis、SEM、AAS、H2-TPR和NH3-TPD等技术对催化剂进行表征.结果表明,CoH-FBZ为均匀单一物相,XRD和FT-IR谱图中,FAU和BEA拓扑结构特征峰明显,NH3-TPD结果表明,双拓扑结构H-FBZ和CoH-FBZ中产生了新的强酸位.CoH-FBZ较CoH-Beta与CoH-Y机械混合样品的催化活性高;CoH-FBZ中FAU与BEA拓扑结构的相对含量FAU/BEA为(0·4∶0·6)^(0·1∶0·9)时,催化剂具有高的CH4-SCR催化活性.强酸位与Co协同作用有利于提高催化剂的CH4-SCR催化活性.Selective catalytic reduction of NO by CH4 （CH4-SCR） in the presences of excess oxygen was studied over CoH-FBZ catalysts with FAU and BEA double micro-porous topology structure. The catalysts were characterized with XRD, FT-IR, SEM, DRS-UV-Vis, NH3-TPD and H2-TPR techniques. The results showed that uniform morphology was observed over the SEM images of CoH- FBZ. Characteristic peaks attributed to FAU and BEA topology structure were observed over the XRD patterns and the FT-IR spectra of the CoH-FBZ catalysts. New strong acidic sites were formed over H-FBZ and CoH-FBZ based on the NH3-TPD results. CoH-FBZ exhibited higher CH4-SCR activity than the physical mixture of CoH-Y and Coil-Beta with comparable relative content of BEA topology structure. Over the physical mixture catalysts of CoH-Y and Coil-Beta, the CH4-SCR activity decreased with increasing relative content of CoH-Y. In contrast, CoH-FBZ in which the relative content of the FAU to BEA topology structure was （0.4 ： 0. 6） - （0. 1 ： 0. 9） exhibited better CH4-SCR catalytic properties. The synergistic effect of the new strong acidic sites promoted the reduction of NO by CH4.

关 键 词：选择催化还原 甲烷 一氧化氮 CoH-FBZ 双微孔 

分 类 号：TQ032.41[化学工程]