Effects of SiO2/Al2O3 ratio, reaction atmosphere and metal additive on de-NOx performance of HC-SCR over Cu-based ZSM-5

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) Vol. 90; pp. 132 - 144
• Main Authors: Lee, Kyungseok, Choi, Byungchul, Lee, Chunbeom, Oh, Kwangchul
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.10.2020; 한국공업화학회
• Subjects: Additives; Cu/ZSM-5; De-NOx; HC-SCR; SiO2/Al2O3ratio; 화학공학; Cu/ZSM-5; HC-SCR; Additives; De-NOx; SiO2/Al2O3ratio
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2020.07.005

[Display omitted] •2Cu(2 wt.%)-ZSM-5 catalysts with various SiO2/Al2O3 ratio were prepared.•2Cu/ZSM-5 with 90 of SiO2/Al3O3 exhibited broad temperature window for NOx reduction.•CO and H2 induced a negative effect on de-NOx performance over 2Cu/ZSM-5.•2Cu1Sn/ZSM-5 improved low-temperature HC-SCR in H2-CO-C3H6-SCR process. This study aims to investigate the catalytic performance of 2Cu/ZSM-5 with different SiO2/Al2O3 ratios (30, 75, and 90) for selective catalytic reduction (SCR) of NOx by C3H6. The coexistent CO and H2 in the C3H6-SCR process were also evaluated to further improve the de-NOx performance. The SiO2/Al2O3 ratios and coexistent CO and H2 significantly affected the de-NOx performance and its operating temperature window. The addition of 1 wt.% metal additives (Pt, Ce, Sn, and Mn) to 2Cu/ZSM-5 exhibited a distinct improvement in catalytic performance. Among the metal-additive catalysts, 2Cu1Sn/ZSM-5 demonstrated favorable NOx conversion in the H2- or CO-C3H6-SCR process owing to the enhancement of partial oxidation of C3H6 by H2. This resulted in improved low-temperature catalytic performance, without any accompanying side reactions that produce NH3, N2O, and HNCO.