A Comparative Study on the Effect of Surface and Bulk Sulfates on the High-Temperature Selective Catalytic Reduction of NO with NH3 over CeO2
Chong Tan, Zhiwen Gu, Songil Sin, Jiawei Ji, Yan Wang, Baiyun Zhu, Lijun Cheng, Chunkai Huang, Lulu Li, Hongliang Zhang, Changjin Tang- Physical and Theoretical Chemistry
- Catalysis
- General Environmental Science
Herein, two CeO2 samples dominantly decorated with surface and bulk sulfates were constructed and their distinct effects on high-temperature NH3-SCR were investigated by strictly controlling the sulfate content at a comparable level. The obtainment of surface and bulk sulfates was revealed using a designed leaching experiment, and further evidenced by the characterization results from XPS and H2-TPR. In comparison with CeO2 modified with bulk sulfates (B-CeS), sufficient acid sites with strong intensity were generated on CeO2 modified with surface sulfates (S-CeS). In addition, due to electron-withdrawing effect from S=O in sulfate species, NH3 oxidation over S-CeS was greatly suppressed, providing an additional contribution to enhanced performance in high-temperature NH3-SCR.