Direct gas-phase epoxidation of propylene to propylene oxide through radical reactions: A theoretical study

Kizilkaya, Ali Can
Fellah, Mehmet Ferdi
Önal, Işık
The gas-phase radical chain reactions which utilize O-2 as the oxidant to produce propylene oxide (PO) are investigated through theoretical calculations. The transition states and energy profiles were obtained for each path. The rate constants were also calculated. The energetics for the competing pathways indicate that PO can be formed selectively due to its relatively low activation barrier (9.3 kcal/mol) which is in a good agreement with the experimental value (11 kcal/mol) of gas-phase propylene epoxidation. The formation of the acrolein and combustion products have relatively high activation barriers and are not favored. These results also support the recent experimental findings.


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In this work, direct growth of graphene is carried out on TiO2 (110) substrates by chemical vapor deposition. For few device applications, it is convenient to grow graphene directly on the dielectric substrates rather than metal foil to minimize transfer and surface interface defects. Raman spectrum support graphene growth on TiO2 substrate by exhibiting D and G peaks. Graphene covered the whole TiO2 substrate with few areas where higher growth of carbon atoms occurs. The contrast of SEM images clearly show...
Citation Formats
A. C. Kizilkaya, M. F. Fellah, and I. Önal, “Direct gas-phase epoxidation of propylene to propylene oxide through radical reactions: A theoretical study,” CHEMICAL PHYSICS LETTERS, pp. 183–189, 2010, Accessed: 00, 2020. [Online]. Available: