Thermochemical and kinetic analysis on the addition reactions of H, O, OH, and HO2 with 1,3 cyclopentadiene

Abstract

Chemical activation and unimolecular dissociation pathway kinetic analysis is presented on addition of radicals H, O, OH, and HO 2 to one of the two types of unsaturated carbons on cyclopentadiene. Addition of H atom or OH radical at the 1 position forms an allylic radical, which can break the weaker (allylic) bond, opening the 5-carbon9carbon carbon ring and forming a resonance stabilized radical. Addition at the 2 position is less exothermic and forms a secondary radical, which can break a bond to form carbon9carbon a vinylic radical. The vinylic radical, if formed will rapidly react with O2 or decompose, ␤ Scission. Addition at the 2 position usually results in reverse reaction (dissociation back to the reactants) O (3P) addition to the two types of unsaturated carbons on cyclopentadiene will form two diradical isomers which will quickly decompose to H atom plus cyclopentenone-yl radicals, both of these cyclopentenone-yl radicals will undergo ␤ Scission to form stable cyclopentadienone and H atom.HO 2 addition to the unsaturated carbons on cyclopentadiene can form the cyclopentenyl (allylic) radical plus O 2 as products through intramolecular isomerization (H Shift) and then dissociation.Thermochemical property data for intermediate species along with rate constants for these radical addition reactions to cyclopentadiene and the decomposition/isomerization reactions of the adducts are estimated. Rate constants for each channel are calculated using bimolecular quantum Rice Ramsperger Kassel, QRRK, for k(E) with a modified strong collision analysis for fall off. Rate constants are presented over a range of pressure and temperature. Modeling results are compared to the limited literature data available for validation, i.e., to species profiles for appropriate reaction systems, where cyclopentadiene is a key intermediate.Rate constants on abstraction of the resonance stabilized H from the cyclopentadiene ring are also estimated.Major (vida infra) reaction channels and kinetic parametersCorrespondence to:

Experimental and kinetic modeling study of the oxidation of benzene

“…The C 5 hydrocarbon subset is mainly adopted from the recent work of Zhong and Bozzelli [17,18,35], while the C 3 -C 4 hydrocarbon chemistry is based on the work of Miller and co-workers [24,27] and Marinov et al [28]. The C 1 -C 2 /NO subset has been adopted without changes from Glarborg et al [29].…”

“…Thermodynamic data were taken mostly from the Sandia Thermodynamic Database [30], Burcat and McBride [31], and Zhong and Bozzelli [17,18,35]. Appendix B lists thermodynamic properties (⌬H f298 , S f298 , and C p ) for selected species.…”

“…The availability of thermodynamic properties is also enhanced [17,18,23,28,30,31], although significant uncertainties remain.…”

Numerical Simulation of the Acenaphthylene Compound in an Atmospheric Plasma Reactor to Treat Cooking Fumes

“…Cyclopentadienyl further forms A1 by reacting with methyl radicals in the main reaction zone and in the post-flame zone. Zhong and Bozzelli (1997) proposed a submechanism of important cyclopentadienyl (C 5 H 6 ) radical reactions and tested it in an elementary model for benzene combustion.…”

Analysis of an elementary reaction mechanism for benzene oxidation in supercritical water

“…In the SCWO-mechanism, we computed rate coefficients using CHEMDIS for the addition and combination reactions of C 5 H 5 and C 5 H 6 at 246 bar from 300 to 1000 K using the data presented in Zhong and Bozzelli [47,48]. Reactions with the highest rate coefficients at 813 K and 246 bar were included in the benzene SCWO mechanism, according to which C 5 H 5 from reaction R4 reacts primarily by reaction R8: Since the oxidation of benzene proceeds mainly by reaction R6, the reaction delay (or induction time) and the subsequent rate of benzene reaction are determined by the rate of OH radical generation, which, in the present mechanism, is primarily by reaction R8.…”