| Ce、Mn助剂对V2O5/TiO2催化剂催化氨选择性氧化的影响 |
| Effects of Ce and Mn promoters on the selective oxidation of ammonia over V2O5/TiO2 catalyst |
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| 摘要: 以V2O5/TiO2催化剂为基体，制备了一系列Ce、Mn改性催化剂，并结合氮气吸附-脱附、X射线衍射、X射线光电子能谱、扫描电子显微镜分析了催化剂的结构及活性组成，探究了其反应活性。结果表明，制备的改性V2O5/TiO2催化剂分散性好，Ce-Mn双金属改性提高了催化剂的NH3转化率和N2选择性。Ce、Mn负载量(Ce或Mn与TiO2的质量比)分别为8%、6%时，310℃下改性材料的NH3转化率为100%，N2选择性为78%。原位漫反射傅里叶变换红外光谱表征显示催化剂表面羟基吸附的NH3会优先参与反应，温度升高后催化剂表面的Brønsted和Lewis酸位点上吸附的NH3开始参与反应，较高温度下Lewis酸位点是主要的NH3转化位点。 |
| 关键词: 氨选择性氧化 V2O5/TiO2 催化剂 氧化 载体 金属助剂 反应机理 |
| 基金项目: 国家重点研发计划(No.2021YFC2902603)资助。 |
| Abstract: A series of Ce, Mn-modified catalysts were prepared based on the V2O5/TiO2 catalyst matrix, and the structure and active components of the catalysts were analyzed using nitrogen adsorption-desorption, X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscope. The reaction activity was also explored. The results indicated that the prepared modified V2O5/TiO2 catalysts had good dispersion, and the Ce-Mn bimetalmodification improved the NH3 conversion rate and N2 selectivity of catalysts. When the loading amounts of Ce and Mn (the mass ratio of Ce or Mn to TiO2) were 8% and 6%, respectively, the NH3 conversion rate of the modified material reached 100% at 310 ℃, with an N2 selectivity of 78%. In-situ diffuse reflectance Fourier transform infrared spectroscopy characterization showed that NH3 adsorbed on the surface hydroxyl groups of the catalyst would preferentially participate in the reaction. As the temperature increased, NH3 adsorbed on the Brønsted and Lewis acid sites on the catalyst surface began to participate in the reaction, and at higher temperatures, the Lewis acid sites were the main sites for NH3 conversion. |
| Keywords: selective oxidation of ammonia V2O5/TiO2 catalyst oxidation support metal promoter reaction mechanism |
| 投稿时间：2024-06-04 修订日期：2024-11-15 |
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| 岳鹏,石丽瑶,崔静磊,张慧荣,郭彦霞.Ce、Mn助剂对V2O5/TiO2催化剂催化氨选择性氧化的影响[J].无机化学学报,2025,41(2):293-307. |
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