Journal
COMBUSTION AND FLAME
Volume 159, Issue 11, Pages 3423-3436Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.combustflame.2012.06.004
Keywords
PAH; Soot; Oxidation; Kinetic mechanism; Density functional theory; Transition state theory
Categories
Funding
- Saudi Aramco, KSA through KAUST CCRC
Ask authors/readers for more resources
The reaction pathways for the oxidation by O-2 of polycyclic aromatic hydrocarbons present in soot particles are investigated using density functional theory at B3LYP/6-311++G(d,p) level of theory. For this, pyrene radical (4-pyrenyl) is chosen as the model molecule, as most soot models present in the literature employ the reactions involving the conversion of 4-pyrenyl to 4-phenanthryl by O-2 and OH to account for soot oxidation. Several routes for the formation of CO and CO2 are proposed. The addition of O-2 on a radical site to form a peroxyl radical is found to be barrierless and exothermic with reaction energy of 188 kJ/mol. For the oxidation reaction to proceed further, three pathways are suggested, each of which involve the activation energies of 104,167 and 115 kJ/mol relative to the peroxyl radical. The effect of the presence of H atom on a carbon atom neighboring the radical site on the energetics of carbon oxidation is assessed. Those intermediate species formed during oxidation with seven-membered rings or with a phenolic group are found to be highly stable. The rate constants evaluated using transition state theory in the temperature range of 300-3000 K for the reactions involved in the mechanism are provided (C) 2012 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available