Effects of Hydrothermal Aging on NH3-SCR reaction over Cu/zeolites

Journal Article · Mon Feb 06 04:00:00 EST 2012 · Journal of Catalysis

DOI:https://doi.org/10.1016/j.jcat.2011.12.025· OSTI ID:1034968

Kwak, Ja Hun; Tran, Diana N; Burton, Sarah D; Szanyi, Janos; Lee, Jong H; Peden, Charles HF

The effects of hydrothermal treatment on model Cu/zeolite catalysts were investigated to better understand the nature of Cu species for the selective catalytic reduction of NO{sub x} by NH{sub 3}. After hydrothermal aging at 800 C for 16 h, the NO{sub x} reduction performance of Cu-ZSM-5 and Cu-beta were significantly reduced at low temperatures, while that of Cu-SSZ-13 was not affected. When the zeolite framework aluminum species were probed using solid state {sup 27}Al-NMR, significant reduction in the intensities of the tetrahedral aluminum peak was observed for Cu-ZSM-5 and Cu-beta, although no increase in the intensities of the octahedral aluminum peak was observed. When the redox behavior of Cu species was examined using H{sub 2}-TPR, it was found that Cu{sup 2+} could be reduced to Cu{sup +} and to Cu{sup 0} fir Cu-ZSM-5 and Cu-beta catalysts, while Cu{sup 2+} could be reduced to Cu{sup +} only for Cu-SSZ-13. After hydrothermal aging, CuO and Cu-aluminate species were found to form in Cu-ZSM-5 and Cu-beta, while little changes were observed for Cu-SSZ-13.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1034968
• Report Number(s): PNNL-SA-81754; 35404; VT0401000
• Journal Information: Journal of Catalysis, Journal Name: Journal of Catalysis Journal Issue: 1 Vol. 287; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AGING
ALUMINIUM
CATALYSTS
COPPER
Environmental Molecular Sciences Laboratory
PERFORMANCE
SELECTIVE CATALYTIC REDUCTION
TEMPERATURE DEPENDENCE
ZEOLITES