Xu Wensheng, Tian Ruixue, Gao Chunlin, Wang Chenghao, Chen Yuxin, Wang Ruifen, Peng Jun, An Shengli, Li Peizhong
School of Rare Earth Industry, Inner Mongolia University of Science and Technology, Baotou, 014010, China.
Key Laboratory of Green Extraction and Efficient Utilization of Light Rare-Earth Resources, Ministry of Education, Baotou, 014010, China.
Sci Rep. 2024 Oct 9;14(1):23604. doi: 10.1038/s41598-024-71933-y.
The catalyst is based on CeO cannot be widely used in SCR reaction because of its poor NH adsorption performance. In this study, Cu-doped CeTi catalyst was designed. The results show that the CeTiCu0.3 has a wide active temperature window of 200-450 °C in NH-SCR reaction, and NO conversion is > 80%. This is mainly due to the fact that Cu doping provides more acidic sites on the surface of CeTi catalyst, especially the increase of Lewis acid sites is more obvious. NH-TPD showed that CeTiCu0.3 had a large NH adsorption capacity and was mainly adsorbed at Lewis acid sites. In situ DRIFTs results show that NH first adsorbs on the Lewis acid site of catalyst in coordination state and reacts with gaseous NO, while NO adsorbed on catalyst surface has low reactivity. Therefore, the CeTiCu0.3 catalyst is mainly controlled by the Eley-Rideal mechanism. More Lewis acid sites, and abunda nt Cu/Cu and Ce/Ce formed Cu, Ce and surface reactive oxygen species are the main reasons for the excellent catalytic performance of CeTiCu.
基于CeO的催化剂由于其较差的NH吸附性能而不能广泛应用于SCR反应。本研究设计了Cu掺杂的CeTi催化剂。结果表明，CeTiCu0.3在NH-SCR反应中具有200-450℃的宽活性温度窗口，NO转化率>80%。这主要是因为Cu掺杂在CeTi催化剂表面提供了更多的酸性位点，尤其是Lewis酸位点的增加更为明显。NH-TPD表明CeTiCu0.3具有较大的NH吸附容量，且主要吸附在Lewis酸位点上。原位DRIFTs结果表明，NH首先以配位态吸附在催化剂的Lewis酸位点上并与气态NO反应，而吸附在催化剂表面的NO反应活性较低。因此，CeTiCu0.3催化剂主要受Eley-Rideal机理控制。更多的Lewis酸位点，以及形成的丰富的Cu/Cu和Ce/Ce、Cu、Ce和表面活性氧物种是CeTiCu优异催化性能的主要原因。
