采用等体积浸渍法制备了Mn-Fe/CeO2-TiO2催化剂,考察了不同焙烧温度对其NH3选择性催化还原(SCR) NO活性及催化剂性能的影响.并用N2吸附-脱附,X射线衍射(XRD)和X射线光电子能谱(XPS)等手段对催化剂进行了表征.活性结果表明,随着焙烧温度的升高,Mn-Fe./CeO2-TiO2催化剂的催化活性先升高后降低.其中焙烧温度为500℃时Mn/CeO2-TiO2的NH3-SCR活性最佳,该催化剂在113 ～ 250℃之间表现出了良好NO去除效率.表征结果表明,500℃焙烧时,催化剂中Fe和Mn物种在CeO2-TiO2表面的分散效果最好.500℃焙烧时Mn-Fe/CeO2-TiO2表面Mn以+4价存在,Fe以+3、+2价存在,而Ce以+4、+3存在.%The Mn-Fe/CeO2-TiO2 catalyst was prepared by the incipient wetness method,the influence of calcination temperature on the property and catalytic activity of Mn-Fe/CeO2 -TiO2 was studied for selective catalytic reduction( SCR) of NO by NH3. The catalysts were characterized by N2-adsorption-desorption, X-ray diffraction and X-ray photoelectron spectroscopy. The performance results showed that the catalytic activities were fust increased and subsequently decreased with the increase of calcination temperature. The catalyst calcined at 500℃ showed the best activity for NO reduction by NH3, and this catalyst exhibited high NO conversion in a wide temperature range of 113-250℃. The characterization results revealed that the Mn-Fe/CeO2-TiO2 catalyst calcined at 500℃ promoted the dispersion of Mn and Fe species on CeO2-TiO2. The XPS results indicated that the Mn species was existed in a valence of +4. Fe species was existed as a mixed valence of +3 and+2 and Ce species was a mixed valence of existed as +4 and +3.
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