H_2O和SO_2对V_2O_5/TiO_2催化剂选择性催化还原烟气脱硝性能的影响  

Effects of H_2O and SO_2on the Performance of V_2O_5/TiO_2 Catalysts for Selective Catalytic Reduction of NO in Flue Gas

作　　者：姜烨[1] 高翔[2] 吴卫红[2] 

机构地区：[1]中国石油大学(华东)储运与建筑工程学院,山东省青岛市266580 [2]能源清洁利用国家重点实验室(浙江大学),浙江省杭州市310027

出　　处：《中国电机工程学报》2013年第20期28-33,7,共6页Proceedings of the CSEE

基　　金：浙江省重大科技专项项目(2011C13020);山东省自然科学基金项目(ZR2011EEQ004);中央高校基本科研业务费专项项目(12CX06076A)~~

摘　　要：通过浸渍法制备了V2O5/TiO2催化剂,考察了H2O和SO2对该催化剂NH3选择性催化剂还原NO性能的影响。结果表明,H2O对V2O5/TiO2催化剂上的选择性催化还原反应具有一定抑制作用,但是同时能够抑制N2O的生成。SO2在干烟气条件和湿烟气条件((H2O)10%)下对V2O5/TiO2催化剂上NO还原活性影响不大。H2O的存在增加了催化剂表面的Br nsted酸性位,提高了NH3在催化剂表面上的吸附。催化剂的脱硝活性随着反应气氛中H2O体积分数的增加而降低,可能是因为大量水蒸气的出现抑制了吸附于Br nsted酸性位上的NH4+离子与NO的反应。SO2在V2O5/TiO2催化剂表面形成SO42,SO42可能增加了表面酸性,有助于提高选择性催化还原反应速率。V2O5/TiO2 catalysts were prepared by an impregnation method.Effects of H2O and SO2 on the performance of the catalysts were investigated in the selective catalytic reduction of NO with NH3.The results show that H2O exhibits an inhibiting effect on the selective catalytic reduction（SCR）,but it reduces the formation of N2O.SO2has no large impact on the activity of NO reduction over the catalysts in dry or wet simulated flue gas（（H2O） 10%）.The presence of H2O increases the amount of the Br nsted acid sites on the catalysts’ surface,thereby increasing the amount of adsorbed NH3.The deNOx activity decreases with the increase of the volume fraction of H2O in flue gas.The reason is that a large amount of H2O depressed the reaction of NO with NH4＋ adsorbed on Br nsted acid sites.SO2 is transformed to SO42 over the catalysts’ surface.SO42 can enhance the acidity of the catalysts’ surface,thereby increasing the speed of SCR reaction.

关 键 词：烟气脱硝 选择性催化还原 V2O5 TIO2催化剂 H2O SO2 活性 

分 类 号：X511[环境科学与工程—环境工程]