TY - JOUR
T1 - Theoretical study on the thermodynamic properties and self-decomposition of methylbenzenediol isomers
AU - Altarawneh, Mohammednoor
AU - Al-Muhtaseb, Ala'A H.
AU - Dlugogorski, Bogdan Z.
AU - Kennedy, Eric M.
AU - MacKie, John C.
PY - 2010/11/4
Y1 - 2010/11/4
N2 - Alkylated hydroxylated aromatics are major constituents of various types of fuels, including biomass and low-rank coal. In this study, thermochemical parameters are obtained for the various isomeric forms of methylbenzenediol isomers in terms of their enthalpies of formation, entropies, and heat capacities. Isodesmic work reactions are used in quantum chemical computations of the reaction enthalpies for O-H and H2C-H bond fissions and the formation of phenoxy- and benzyl-type radicals. A reaction potential energy on the singlet-state surface surface is mapped out for the unimolecular decomposition of the 3-methylbenzene-1,2-diol isomer. According to the calculated high pressure-limit reaction rate constants, concerted hydrogen molecule elimination from the methyl group and the hydroxyl group, in addition to intermolecular H migration from the hydroxyl group, dominates the unimolecular decomposition at low to intermediate temperatures (T ≤ 1200 K). At higher temperatures, O-H bond fission and concerted water elimination are expected to become the sole decomposition pathways.
AB - Alkylated hydroxylated aromatics are major constituents of various types of fuels, including biomass and low-rank coal. In this study, thermochemical parameters are obtained for the various isomeric forms of methylbenzenediol isomers in terms of their enthalpies of formation, entropies, and heat capacities. Isodesmic work reactions are used in quantum chemical computations of the reaction enthalpies for O-H and H2C-H bond fissions and the formation of phenoxy- and benzyl-type radicals. A reaction potential energy on the singlet-state surface surface is mapped out for the unimolecular decomposition of the 3-methylbenzene-1,2-diol isomer. According to the calculated high pressure-limit reaction rate constants, concerted hydrogen molecule elimination from the methyl group and the hydroxyl group, in addition to intermolecular H migration from the hydroxyl group, dominates the unimolecular decomposition at low to intermediate temperatures (T ≤ 1200 K). At higher temperatures, O-H bond fission and concerted water elimination are expected to become the sole decomposition pathways.
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U2 - 10.1021/jp1054765
DO - 10.1021/jp1054765
M3 - Article
C2 - 20931952
AN - SCOPUS:78049524609
SN - 1089-5639
VL - 114
SP - 11751
EP - 11760
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 43
ER -