研究了不同载体(γ - Al2O3 HZSM -5、TiO2、SiO2和MgO)负载Fe催化剂上CO还原NO反应及CO同时还原NO和SO2反应.结果表明,Fe/γ - Al2O3催化剂对CO与NO反应具有良好的催化活性,但随着反应时间的延长,催化剂很快失活；在CO和NO反应中加入SO2,可以明显改善Fe/γ-Al2O3催化剂对CO还原NO反应的活性稳定性；O2和H2O对催化剂活性的影响较大,CO2对催化剂的影响较小.XRD结果表明,FeS2是催化剂的活性中心,在CO与NO反应后,FeS2转变为催化惰性的Fe7S8而导致催化剂活性下降；在CO与NO及SO2反应体系中引入O2后,Fe/γ - Al2O3催化剂上的活性组分FeS2被氧化为Fe2O3,导致催化剂失活.%The catalysts supported with iron on different carriers (γ-Al2O3, HZSM-5 , TiO2, SiO2, MgO) were investigated for the catalytic reduction of NO and simultaneous catalytic reduction of NO and SO2 by CO. The results showed that Fe/γ-Al2O3 catalyst had better initial activity for reduction of NO by CO,but its activity decreased rapidly with prolonging the reaction time. The stability of Fe/γ-Al2O3 catalyst for NO reduction by CO was improved significantly by adding SO2. O2 and H2O had negative effect on the catalytic activity of Fe/γ-Al2O3 while CO2 had little influence. The results of XRD characteration showed that FeS2 was the active site of Fe/γ-Al2O3 catalyst;after the conversion reaction of NO and CO,FeS2 was transformed into Fe7S8,which resulted in the decrease of the catalytic activity of Fe/γ-Al2O3. When O2 was added in the reaction system, active component FeS2 was oxidized to Fe2 O3, which caused the deacti-vation of Fe/γ-Al2O3 catalyst.
展开▼
