Abstract
The structural and catalytic properties of supported MoO 3/Al 2O 3 catalysts with Mo surface densities, n s , in the range 1.1–12.5 Mo/nm 2 were studied for the oxidative dehydrogenation of ethane by in situ Raman spectroscopy with simultaneous catalytic measurements at temperatures of 400–550 °C. Isolated mono-molybdates (MoO 4) and polymolybdates are formed at various proportions (depending on the loading) on the catalyst surface under dehydrated conditions; bulk Al 2(MoO 4) 3 crystals are formed at n s exceeding the monolayer. Under reactive environment (C 2H 6/O 2), the Raman features attributed to Mo O and Mo O Mo modes appear to be perturbed, indicating that surface MoO x species are reduced to lower valence states. The combined information on catalyst structure under reaction conditions and catalytic data shows a concurrence between the trends for activity per Mo (turnover frequency [TOF]) and for the number of Mo O Al bonds per Mo as a function of n s . The catalytic activity is related to the anchoring Mo O support bonds. Structure–activity/selectivity relations are derived and discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
