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制备了一系列不同Mn/(Mn+Ce)质量比的MnOx-CeO2/WO3-ZrO2整体式催化剂用于富氧条件下的NH3选择性催化还原NOx(NH3-SCR),并采用N2吸脱附、储氧量、X射线衍射、X光电子能谱、NH3/NO程序升温脱附以及H2程序升温还原等手段对催化剂进行表征.结果表明,当Mn/(Mn+Ce)质量比为0.5时,整体式催化剂具有较好的NH3-SCR性能,在空速10000h-1和173~355oC条件反应下,NOx转化率达90%以上.这是由于该MnOx-CeO2/WO3-ZrO2催化剂具有更高的NO氧化活性、更高的表面Ce和Mn原子浓度以及Ce3+/Ce值较低的NH3和NO脱附温度以及优异的氧化还原性能所致.
A series of MnOx-CeO2 / WO3-ZrO2 monolithic catalysts with different Mn / (Mn + Ce) mass ratios were prepared for NH3 selective catalytic reduction of NOx (NH3-SCR) under oxygen enrichment conditions. , Oxygen storage capacity, X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed desorption of NH3 / NO and temperature-programmed reduction of H2 were used to characterize the catalyst.The results showed that when the mass ratio of Mn / The monolithic catalyst has good NH3-SCR performance, and the NOx conversion rate is more than 90% under the condition of space velocity of 10000h-1 and 173 ~ 355oC. This is because the MnOx-CeO2 / WO3-ZrO2 catalyst has a higher NO oxidation activity, higher surface Ce and Mn atomic concentrations, and lower desorption temperatures of NH3 and NO with lower Ce3 + / Ce values as well as excellent redox properties.