摘要
采用浸渍法制备了一系列不同Cu含量的Cu-ZSM-5催化剂,并用于NH3选择性催化还原(SCR)NO反应.结果表明,当Cu含量为8%时,Cu-ZSM-5催化剂的活性最高;当空速为30000h-1,在198～440oC反应时NO转化率均高于80%,最高可达97%,且空速的影响较小.经快速水热老化后,该催化剂活性明显优于商用V基催化剂.H2O和SO2对Cu-ZSM-5催化剂的SCR活性有所影响,但可明显恢复.X射线衍射和NH3程序升温脱附结果表明,当Cu-ZSM-5中Cu含量为8%时,进入ZSM-5中阳离子位的Cu较多,催化剂的活性较高,且其表面具有较多的酸中心和酸量,从而有利于SCR反应.
A series of Cu-ZSM-5 catalyst samples with different Cu contents were prepared by an incipient wetness impregnation method and were used for selective catalytic reduction（SCR） of NO with NH3.The results showed that the Cu-ZSM-5 with 8% Cu loading had the highest catalytic activity.The conversion of NO was above 80% at 198–440℃,and the highest conversion was 97% at a space velocity of 30000 h–1.The space velocity had less influence on the catalytic activity,and the catalytic activity temperature window was still wide at a space velocity of 60000 h–1.After hydrothermal aging,the catalytic activity of the Cu-ZSM-5 was significantly higher than that of the commercial V-based catalyst.The addition of H2O and SO2 lead to the reduced activity;however,the catalytic activity was still good.X-ray diffraction and NH3 temperature-programmed desorption results indicated that more Cu immigrated into the cation sites of ZSM-5 and the active sites of the catalyst increased when the Cu content reached 8%.Moreover,the Cu-ZSM-5 had more surface acidity centers and surface acidity,which were beneficial to SCR reaction.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
2010年第11期1411-1416,共6页
基金
国家自然科学基金(20333030
20273043)
