采用Zr对CeO2/TiO2催化剂进行改性,考察Zr掺杂对CeO2/TiO2催化剂NH3选择性催化还原NO性能的影响,利用静态N2物理吸附、X射线衍射(XRD)、NH3程序升温脱附(NH3-TPD)和X射线光电子能谱(XPS)对其脱硝机制进行分析.结果表明,Zr掺杂能够拓宽CeO2/TiO2催化剂的温度窗口,提高其脱硝活性和抗H2 O/SO2性能.Zr掺杂能够增大CeO2/TiO2催化剂的比表面积和总孔容,抑制载体锐钛矿TiO2发生晶相转变,显著提高催化剂的表面酸性,增加催化剂表面Ce3+和化学吸附氧的原子浓度,使得催化剂表面NH3吸附能力加强,氧化还原能力提高,有助于促进SCR反应的进行.%Zr was used to modify the CeO2/TiO2 catalyst. The effect of Zr doping on the selective catalytic reduction of NO with NH3 over CeO2/TiO2 catalyst was investigated and their deNOx mechanism was analyzed by the static N2 physical adsorp-tion, X-ray diffraction ( XRD) , NH3-temperature programmed desorption ( NH3-TPD) , and X-ray photoelectron spectrosco-py ( XPS) . The results indicate that Zr doping could widen the temperature window of the CeO2/TiO2 catalyst and improve its activity and resistance to H2 O and SO2 . Zr doping could enlarge the BET surface-volume ratio and total pore volume of the catalyst, inhibit the transformation of crystalline phase of anatase TiO2 carrier, markedly enhance the surface acidity and in-crease the concentration of Ce3+ and chemisorbed oxygen on the catalyst surface. It could also enhance the ability to adsorb NH3 and increase the redox ability, thereby promoting the SCR reaction.
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