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论文类型： 期刊论文

发表时间： 2013-01-31

发表刊物： APPLIED CATALYSIS A-GENERAL

收录刊物： SCIE、EI

卷号： 451

页面范围： 176-183

ISSN号： 0926-860X

关键字： Lewis acidity; Hydrotalcite; Temperature-programmed desorption; In situ FTIR

摘要： The selective catalytic reduction (SCR) of NO by C3H6 has been studied over a series of calcined hydrotalcite, which were prepared by four different methods to obtain various Lewis acid sites. The catalysts have been investigated by X-ray powder diffractometer, N-2 adsorption, Temperature-programmed desorption of NH3 (NH3-TPD), pyridine adsorption FTIR (Py-FTIR), Temperature-programmed desorption of NO + O-2 (NO + O-2-TPD) and in situ FIR techniques. The Lewis acid sites could be changed with the transformation of the crystalline structure from the mixed oxides of MgO and Al2O3 to spinel phase. It is demonstrated that Lewis acid sites play an important role in determining the catalytic performance of SCR by C3H6 over calcined hydrotalcite catalysts. Various nitrate species as the key intermediate species for SCR could form at Lewis acid sites during the process of the reaction under lean-burn condition. (C) 2012 Elsevier B.V. All rights reserved.