Oxidative Dehydrogenation of Ethane over V₂O₅(001):  A Periodic Density Functional Theory Study

Abstract

Oxidative dehydrogenation (ODH) of ethane over the V 2 O 5 (001) surface has been carried out using periodic density functional theory (DFT) calculations. We show that the first C-H bond activation leading to an ethoxide intermediate is the rate-limiting step of the reaction. The most feasible pathway for the C-H bond activation is predicted to take place at the O(1) (VdO) site, with activation energy of 35.1 kcal/mol. The O(2) (V-O-V) site is less active for C-H bond activation, with an energy barrier of 37.6 kcal/mol. However, the O(1) site exhibits much lower selectivity to ethene formation than O(2) because the side reaction leading to acetaldehyde occurs more easily than ethene production on O(1), whereas O(2) is inert for acetaldehyde formation. On the basis of our results, the ODH reactions of ethane and propane are systematically compared and discussed.

Process Development and DFT‐Assisted Mechanism of the Vapour Phase Ammoxidation of 2,6‐Dichlorotoluene to 2,6‐Dichlorobenzonitrile over the V2O5/γ‐Al2O3 Catalyst

“…Figure B it is seen that catalyst model includes three types of oxygen atoms but does not contain support molecule. The optimized bond distances V=O 1.57 Å and V−O 1.77 Å, are in good agreement with the experimental values of V=O 1.58 Å and V−O 1.78 Å obtained for the bulk V 2 O 5 …”

The effect of a silica support: a density functional theory study of the C-H bond activation of ethane on a nickel oxide cluster

“…A reaction mechanism containing the first pathway is denoted as mechanism A, and a reaction mechanism containing the second pathway is denoted as mechanism B in this paper. Similar mechanisms for the C-H bond activation of C 2 H 6 in particular and of small alkanes in general on V-based [31][32][33] and Mo-based [34] catalysts, on Ni(011) surface with and without Nb dopant, [16] and on zeolite-supported Ga catalyst [20] have also been reported.…”

Ethylbenzene dehydrogenation to styrene with CO 2 over V 2 O 5 (001): A periodic density functional theory study

“…The exchange and correlation interaction are modeled using the Perdew -Burke -Ernzerh of functional (PBE) within the generalized gradient approximation (GGA) (Dai et al, 2008). A plane-wave energy cut-off of 500 eV has been used in all cases.…”