Abstract
The reactivity of double bond type lattice oxygen Mo6+O in supported molybdena catalyst has been investigated by means of ESR and ir spectroscopy. It has been shown that the double bond oxygen is similar to a free radical oxygen in nature, in contrast to σ-bond oxygen MoOMo. This character increases as a result of electron transfer from an adsorbed olefin species to a nonbonding atomic orbital of Mo6+ with some decrease in the strength of MoO bond during vapor-phase oxidation of lower olefins. The reactivity of the double bond oxygen as a radical increases inversely with the electronegativity of the molybdenum ion as modified with an oxide of a VA group element or of an alkali metal. This was supported by studies of the catalysis of the oxidation of propylene to acrolein, of butadiene to maleic anhydride and the oxidative dehydrogenation of trans-2-butene to butadiene. On the other hand, the activity for these reactions of catalyst modified with a high concentration of alkali metal oxide increases with the electronegativity of the alkali metal. This different effect due to the concentration of the alkali metal oxide is also discussed.
Sign-in/Register to access full text options 
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.
