Effect of Zr Addition on the Low-Temperature SCR Activity and SO2 Tolerance of Fe–Mn/Ti Catalysts

• Published in: Journal of physical chemistry. C 2014-07, Vol.118 (27), p.14866-14875
• Main Authors: Jiang, Boqiong, Deng, Boyang, Zhang, Zhanquan, Wu, Zuliang, Tang, Xiujuan, Yao, Shuiliang, Lu, Hao
• Format: Article
• Language: eng ; jpn
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp412828p

Zr is added to the Fe–Mn/Ti catalyst to increase NO conversion and improve SO2 tolerance. It is found that 0.03 is the optimal ratio for Zr/(Ti + Zr). With this ratio, the NO conversion below 150 °C increases, and the SO2 poisoning is alleviated, while the further increase of Zr does not have a positive effect on NO conversion and SO2 tolerance. With Zr additive, more manganese oxides are reduced in the form of MnO2 and Mn2O3 at lower temperature in H2-TPR, and the total amount of H2 consumption rises, indicating better redox properties. It leads to the increase of NO complexes on the catalysts. Despite the small decrease of NH3 adsorption, the reaction via the L–H way is promoted and NO conversion increases. Furthermore, more nitrates and NO2 are formed in the reaction with SO2 on Fe–Mn/Ti–Zr(0.03) compared to Fe–Mn/Ti, so the L–H reaction way is less inhibited by SO2 with Zr additive, and the SO2 tolerance of this catalyst is also improved.