ISSN:
1572-879X
Keywords:
in situ FTIR
;
oxygen species
;
LaOF
;
BaF2/LaOF
;
methane oxidative coupling
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract In situ FTIR spectroscopy was used to characterize the oxygen adspecies and its reactivity with CH4 over LaOF and 15 mol% BaF2/LaOF catalysts at OCM temperature (750-800°C). It was found that gas-phase oxygen was activated on the surface of LaOF and 15 mol% BaF2/LaOF, which had been pretreated under vacuum at 750 or 800°C, forming O 2 - species at high temperature (750-800°C). At 750°C, the adsorbed O 2 - species can react with pure CH4 accompanied by formation of gas-phase C2H4 and CO2, and there is a good correlation between the rate of disappearance of surface O2and the rate of formation of gas-phase C2H4. The O 2 - species was also observed over the catalysts under working condition, and it reacted with CH4 in a manner that was consistent with its role in a catalytic cycle. These results suggest that O 2 - may be the active oxygen species for OCM reaction over these catalysts.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1019037301983
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