| 摘要:采用新型一锅法合成一系列硅铝比不同的Cu-SAPO-34催化剂。合成过程中，硅铝比分别设为0.3、0.4、0.5、0.6、0.7、0.8，通入70 ℃含水10%的空气16 h进行低温水热老化。对新鲜和老化后的催化剂的NOx去除活性、N2选择性进行了实验测定；并进行了BET、XRD、H2-TPR以及NH3-TPD表征实验。结果发现:硅铝比为0.4的Cu-SAPO-34，其NOx去除效率和低温水热老化稳定性都达到最佳。从XRD、H2-TPR、NH3-TPD的表征结果也可以发现:硅铝比为0.4的Cu-SAPO-34催化剂在结构、铜离子特性及分布、表面酸性位点等特征都达到了一个相对优化的状态。由此得出结论:提高Cu-SAPO-34的NH3-SCR性能以及低温水热稳定性的关键是，合成过程中保证硅铝比维持在一个比较小的值。 |
| 关键词: Cu-SAPO-34 分子筛催化剂 低温水热老化 硅铝比 |
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| Impact of Different Si/Al on NH3-SCR Performance and Low-TemperatureHydrothermal Aging Stability of Cu-SAPO-34 |
| Wang Hang,Jiang Han,Lin He,Guan Bin,Huang Zhen |
| Shanghai JiaoTong University, Shanghai 200240 |
| Abstract:A series of Cu-SAPO-34 differed in Si/Al were synthesized using the new method called one-pot. Different Si/Al include 0.3,0.4,0.5,0.6,0.7,0.8, and the condition of aging is 70 ℃,10%H2O,16 h. Then the NOx conversion and N2 selectivity of both fresh and aged samples were tested, and these samples were characterized through BET, XRD, H2-TPR and NH3-TPD. The results show that the Cu-SAPO-34 with 0.4 Si/Al has best NH3-SCR performance and low-temperature hydrothermal aging stability. The characterized results of XRD, H2-TPR, NH3-TPD show that the Cu-SAPO-34 with 0.4 Si/Al reaches a great level in structure, characteristics and distribution of Cu ions, as well as acid sites. So the conclusion is that the key of achieving great NH3-SCR performance and low-temperature hydrothermal aging stability of Cu-SAPO-34 is to keep Si/Al relatively low during synthesization. |
| Key words: Cu-SAPO-34 zeolite catalyst low-temperature hydrothermal aging Si/Al |
