含硫钾盐对V2O5-WO3/TiO2催化剂上SO3生成特性的影响

Effects of Sulfur-containing Potassium Salts on Formation Characteristics of SO3 over V2O5-WO3/TiO2 Catalyst

采用湿式浸渍法制备含硫钾盐催化剂,研究含硫钾盐对SCR催化剂上SO3生成特性的影响,并采用不同分析技术对SCR催化剂特性进行表征。结果表明:K2S2O7和K2SO4能明显提高SO3生成率;随着含硫钾盐质量分数的增加,SO3生成率提高;在410℃下3.6%K2S2O7-SCR催化剂的SO3生成率达到最大;SO2质量浓度为3000 mg/m^3时,3.6%K2S2O7-SCR催化剂的SO3质量浓度最大;含硫钾盐存在时,SCR催化剂的还原性能下降,比表面积减小;含硫钾盐存在时,SCR催化剂表面化学吸附氧质量分数和V^5+质量分数均增大,V^5+=O键的振动峰强度明显增强,SCR催化剂的氧化能力增强。

V-based catalysts with sulfur-containing potassium salts(K2S2O7 and K2SO4)were prepared using wet impregnation method,so as to study the effects of the sulfur-containing potassium salts on the formation characteristics of SO3 over V2O5-WO3/TiO2 catalyst,and to characterize the catalysts by various analytic techniques.Results show that the presence of K2S2O7 and K2SO4 would significantly increase the SO3 formation rate,which achieves the maximumm at 410℃for the SCR catalyst with 3.6%K2S2O7.At the SO2 concentration of 3000 mg/m^3,the SCR catalyst with 3.6%K2S2O7 would generate the largest concentration of SO3.For catalysts with sulfur-containing potassium salts,the reduction property and surface area reduce,while the content of surface chemical adsorption oxygen,the V^5+and the vibration peak strength of V^5+=O bonds increase obviously,resulting in enhanced oxidation ability of the catalysts.