Study of NO decomposition and reduction with methane over Co-ZSM-5 catalysts
- Massachusetts Institute of Technology, Cambridge, MA (United States)
Activities of NO decomposition and reduction with methane over Co{sup 2+} ion-exchanged ZSM-5 were evaluated. and the reaction mechanism was investigated. An initial 90% conversion of NO to N{sub 2} was achieved over Co-ZSM-5 at 450{degrees}C in a 2250 ppm NO-He gas stream, which is 100% higher than the current most stable and active Cu-ZSM-5 at comparable reaction conditions. Even at as low as 200{degrees}C, a 30% conversion of NO to N{sub 2} was observed. At least two different types of catalytic active sites were found to be present for NO decomposition in this catalyst: one appealed at ca 200{degrees}C, the other above 400{degrees}C. The catalyst which lost its decomposition activity remained active for NO reduction with methane, indicating a possible reaction mechanism in which Co{sup 2+} decomposes NO molecule, loses its activity, and is regenerated by intermediates of NO{sub 2} and CH{sub 4} reaction. A need for a different active site for NO reduction with methane cannot been eliminated. Studies of adsorbed species with TGA and Photoacoustic FT-IR will be reported.
- OSTI ID:
- 214604
- Report Number(s):
- CONF-950801--
- Country of Publication:
- United States
- Language:
- English
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