| 不同金属负载对Cr/Al2O3-TiO2催化剂结构及氧化NO性能的影响 |
| Effect of Different Metal Loading on the Structures and Catalytic Oxidation NO Performance of Cr/Al2O3-TiO2 Catalysts |
| 作者 | 单位 | E-mail | | 魏炜 | 广州大学化学化工学院, 能源与催化研究所, 广州 510006 | | | 牟一蒙 | 广州大学化学化工学院, 能源与催化研究所, 广州 510006 | | | 梁红 | 广州大学化学化工学院, 能源与催化研究所, 广州 510006 | lhong@zghu.edu.cn | | 李树华 | 广州大学化学化工学院, 能源与催化研究所, 广州 510006 | | | 乔智威 | 广州大学化学化工学院, 能源与催化研究所, 广州 510006 | | | 彭峰 | 广州大学化学化工学院, 能源与催化研究所, 广州 510006 | fpeng@zghu.edu.cn |
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| 摘要: 采用溶胶-凝胶法和浸渍法制备Cr/Al2O3-TiO2催化剂，在考察不同Cr负载量的基础上，研究不同金属负载与焙烧温度对Cr/Al2O3-TiO2催化剂结构与性能影响。程序升温氧化（TPO）结果表明，当Cr负载量为10%（w/w）时具有较好的催化活性；不同金属负载Cr/Al2O3-TiO2时，负载Co及在焙烧温度为550℃时催化剂具有较好的活性。通过程序升温还原（H2-TPR）表征发现，Co的负载使催化剂的低温氧化还原能力逐渐提高，表明Co-Cr具有较好的协同催化作用。X射线光电子能谱（XPS）表征表明，Co增加了Cr6+和表面吸附氧（Oβ）含量，随着焙烧温度的升高（450~550℃），晶格氧不断向催化剂表面流动，表面化学吸附氧Oβ比例逐渐增加，导致催化活性不断升高，说明Cr6+和Oβ是催化氧化NO的重要活性物种。 |
| 关键词: 负载 Co-Cr/Al2O3-TiO2 焙烧温度 催化氧化 NO |
| 基金项目: 国家自然科学基金（No.21576058），广东省自然科学基金（No.2018A030313516）和广东省发展专项资金（No.201804010449）资助项目。 |
| Abstract: A series of Cr/Al2O3-TiO2 catalysts were successfully synthesized by the combination of sol-gel method and impregnation method for catalytic oxidation of NO. The effects of Cr load, different metal loading and calcination temperature on the physical-chemical properties of Cr/Al2O3-TiO2 catalysts were exhaustively investigated by using different characterization techniques, such as the temperature programmed oxidation (TPO), X-ray diffraction (XRD), H2-temperature programmed reduction (H2-TPR), N2 adsorption-desorption method and X-ray photoelectron spectroscopy (XPS). The TPO results showed that the 10%(w/w) Cr/Al2O3-TiO2 possessed the highest performance. Compared the doping of different metals, Co-Cr/Al2O3-TiO2 obtained excellent catalytic activity and high specific surface area at 550℃ calcination temperature. H2-TPR show that both the Co loading and calcination temperature can significantly improve the low-temperature redox ability of the catalyst, and be beneficial to form more active species of Cr6+, indicating that Co-Cr has good synergistic catalysis. XPS revealed that the Co doping greatly increased the content of Cr6+, surface adsorbed oxygen (Oβ), and oxygen vacancies. Besides, when the calcination temperature increased (450~550℃), the lattice oxygen continuously moved to the surface of catalyst and increased the ratio of Oβ, leading to the further enhancement of catalytic activity of Co-Cr/Al2O3-TiO2. Based the characterization results and catalytic performance of Cr/Al2O3-TiO2, it is proved that both Cr6+ and Oβ are important active species for the catalytic oxidation of NO. |
| Keywords: loading Co-Cr/Al2O3-TiO2 calcination temperature catalytic oxidation NO |
| 投稿时间：2018-12-17 修订日期：2019-03-14 |
| 摘要点击次数: 1239 |
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| 魏炜,牟一蒙,梁红,李树华,乔智威,彭峰.不同金属负载对Cr/Al2O3-TiO2催化剂结构及氧化NO性能的影响[J].无机化学学报,2019,35(6):978-986. |
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