富氧条件下SnO2/Al2O3催化剂上丙烯选择性还原NOx的研究

考察了分别用浸渍法、共沉淀法和溶胶-凝胶法制备的SnO₂/Al₂O₃催化剂上丙烯选择性还原NO_x的催化活性,发现制备方法与Sn的负载量对其活性有重要影响.溶胶-凝胶法制备的SnO₂/Al₂O₃催化剂活性最高,Sn的最佳负载量为5%.与浸渍法和共沉淀法制备的5%SnO₂/Al₂O₃催化剂相比,溶胶-凝胶法制备的5%SnO₂/Al₂O₃催化剂受水蒸汽的抑制作用较弱,并且在水和SO₂共存的条件下活性最高.此外,反应气中丙烯及氧气浓度的增加有利于NO_x转化率的提高.

Selective Reduction of NOx with Propene over SnO2/Al2O3 Catalyst

In the study, a series of SnO₂/Al₂O₃ catalysts with various Sn loading were prepared by three different methods (impregnation, co precipitation and single step sol gel) and their catalytic activities for the selective reduction of NO_x with propene were investigated. It was found that the catalyst preparation method as well as the Sn loading exerted a significant influence on the catalyst activity. Catalysts prepared by sol gel method exhibited the highest activity toward NO x reduction and the optimal Sn loading is 5%. 5%SnO₂/Al₂O₃ catalyst prepared by sol gel method was found to be less inhibited by the presence of H₂O than those prepared by other methods. Even in the co presence of H₂O and SO₂, it still showed the highest activity. The increase of oxygen and propene concentration promotes the NO_x reduction, respectively.