载体结构对锡铁负载型催化剂脱硝性能的影响  

Effect of pore structure on the performance of Sn-Fe supported catalyst in denitration

作　　者：陈凯歌[1,2] 肖峰[2] 蒋晓萍[2] 许琦[2] 

机构地区：[1]常州大学石油化工学院,江苏常州213000 [2]盐城工学院,江苏盐城224000

出　　处：《化工进展》2016年第12期3919-3927,共9页Chemical Industry and Engineering Progress

摘　　要：利用凹凸棒土（ATP）、活性炭（AC）、介孔硅（MCM-41）、二氧化钛（TiO_2）这4种孔结构不同的载体,通过水热法制备了以Fe2O3为催化剂主活性组分、SnO_2为辅活性组分的锡铁负载型催化剂。催化剂的微观结构通过BET和SEM测试,并在催化剂评价装置中模拟烟气组成,考察锡铁负载型催化剂在反应温度为80~280℃、脱硝空速为32000~48000h–1范围内的选择性催化还原（SCR）性能。同时考察了SO_2与H_2O对1/2Sn Fe/ATP催化剂的影响。实验表明,载体可能为催化剂提供大量Br？nsted酸性位点,有利于反应气体吸附。1/2Sn Fe/ATP催化剂表现出最佳的SCR脱硝性能,在200℃时实现最高96.4%的NO转化率,而且由其抗硫性及其抗水性实验表明：SO_2单独作用于催化剂时,脱硝效率降低迟缓,切断二氧化硫后仍能恢复到85%以上。同时加入水和二氧化硫后,将会导致脱硝效率急剧下降。停止加入后,催化剂效率又开始慢慢恢复,效率可以恢复达到70%以上。Four catalyst supports of different pore structures,namely attapulgite（ATP）,activated carbon（AC）,mesoporous silica（MCM-41）and titanium dioxide（TiO_2）,were used to prepare a series of Sn-Fe supported catalysts by the hydrothermal synthesis method with the Fe2O3 as active component,and SnO_2 as auxiliary active component.The materials before and after preparation were characterized by BET and SEM.The denitration performance of the prepared catalysts for artificial flue gas were tested in a catalyst evaluation device in a temperature range of（80—280℃）and space velocity range of（32000—48000h–1）.Meanwhile,the impact of SO_2 and H_2O on the catalyst（1/2Sn Fe/ATP）was investigated.The results showed that carriers might provide a large number of Br？nsted acid sites,which was beneficial for the gas adsorption reaction.Among all the test catalysts,the 1/2Sn Fe/ATP had the best SCR denitration performance.At 200℃,the conversion of NO could reach by 96.4%.It was also found,when there was only SO_2,the NO removal efficiency decreased slowly,and would still be higher than 85% if SO_2 input was cut off.But when H_2O and SO_2 were simultaneously added,the NO removal efficiency fell sharply and would went back to above 70% if H_2O and SO_2 input was cut off.

关 键 词：载体结构 脱硝 负载型催化剂 选择性催化还原 

分 类 号：X511[环境科学与工程—环境工程]