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Kinetics of the hydrogen abstraction alkane + O2 → alkyl + HO2 reaction class: an application of the reaction class transition state theory. Struct Chem 2019. [DOI: 10.1007/s11224-019-01459-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Pelucchi M, Cavallotti C, Faravelli T, Klippenstein SJ. H-Abstraction reactions by OH, HO 2, O, O 2 and benzyl radical addition to O 2 and their implications for kinetic modelling of toluene oxidation. Phys Chem Chem Phys 2018; 20:10607-10627. [PMID: 29387837 DOI: 10.1039/c7cp07779c] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Alkylated aromatics constitute a significant fraction of the components commonly found in commercial fuels. Toluene is typically considered as a reference fuel. Together with n-heptane and iso-octane, it allows for realistic emulations of the behavior of real fuels by the means of surrogate mixture formulations. Moreover, it is a key precursor for the formation of poly-aromatic hydrocarbons, which are of relevance to understanding soot growth and oxidation mechanisms. In this study the POLIMI kinetic model is first updated based on the literature and on recent kinetic modelling studies of toluene pyrolysis and oxidation. Then, important reaction pathways are investigated by means of high-level theoretical methods, thereby advancing the present knowledge on toluene oxidation. H-Abstraction reactions by OH, HO2, O and O2, and the reactivity on the multi well benzyl-oxygen (C6H5CH2 + O2) potential energy surface (PES) were investigated using electronic structure calculations, transition state theory in its conventional, variational, and variable reaction coordinate forms (VRC-TST), and master equation calculations. Exploration of the effect on POLIMI model performance of literature rate constants and of the present calculations provides valuable guidelines for implementation of the new rate parameters in existing toluene kinetic models.
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Affiliation(s)
- M Pelucchi
- Department of Chemistry, Materials and Chemical Engineering "G. Natta", Politecnico di Milano, Milan, Italy.
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Zhou CW, Simmie JM, Somers KP, Goldsmith CF, Curran HJ. Chemical Kinetics of Hydrogen Atom Abstraction from Allylic Sites by 3O2; Implications for Combustion Modeling and Simulation. J Phys Chem A 2017; 121:1890-1899. [DOI: 10.1021/acs.jpca.6b12144] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chong-Wen Zhou
- Combustion Chemistry Centre & School of Chemistry, National University of Ireland, Galway H91 TK33, Ireland
| | - John M. Simmie
- Combustion Chemistry Centre & School of Chemistry, National University of Ireland, Galway H91 TK33, Ireland
| | - Kieran P. Somers
- Combustion Chemistry Centre & School of Chemistry, National University of Ireland, Galway H91 TK33, Ireland
| | - C. Franklin Goldsmith
- School
of Engineering, Brown University, Providence, Rhode Island 02912, United States
| | - Henry J. Curran
- Combustion Chemistry Centre & School of Chemistry, National University of Ireland, Galway H91 TK33, Ireland
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Li SH, Guo JJ, Li R, Wang F, Li XY. Theoretical Prediction of Rate Constants for Hydrogen Abstraction by OH, H, O, CH3, and HO2 Radicals from Toluene. J Phys Chem A 2016; 120:3424-32. [DOI: 10.1021/acs.jpca.6b03049] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shu-Hao Li
- School
of Aeronautics and Astronautics, Sichuan University, Chengdu 610065, China
| | - Jun-Jiang Guo
- School
of Chemical Engineering, Sichuan University, Chengdu 610065, China
| | - Rui Li
- School
of Aeronautics and Astronautics, Sichuan University, Chengdu 610065, China
| | - Fan Wang
- Institute
of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Xiang-Yuan Li
- School
of Chemical Engineering, Sichuan University, Chengdu 610065, China
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Bentz T, Szőri M, Viskolcz B, Olzmann M. Pyrolysis of Ethyl Iodide as Hydrogen Atom Source: Kinetics and Mechanism in the Temperature Range 950–1200 K. Z PHYS CHEM 2011. [DOI: 10.1524/zpch.2011.0178] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Ethyl iodide is a well known H atom precursor in shock tube experiments. In the present work, we study peculiarities, when C2H5I is used under conditions, where its decomposition is not longer fast compared to consecutive bimolecular reactions. On the basis of shock tube experiments with detection of H and I atoms by resonance absorption spectrometry, accompanied by quantum chemical (CCSD(T)/6-311G//CCSD/6-311G) and statistical rate theory calculations, we propose a small mechanism (5 reactions, 7 species) and kinetic data, which allow an adequate description of C2H5I pyrolysis as a H atom source down to temperatures between 950 and 1200 K at pressures ranging from 1 to 4 bar: C2H5I→C2H5 + I (1), k
1 = 9.9 × 1012 exp(−23200 K/T) s−1; C2H5 + M→C 2H4 + H + M (2), k
2 = 1.7 × 10−6 exp(−16800 KT) cm3 s−1 [D. L. Baulch et al., J. Phys. Chem. Ref. Data 34 (2005) 757]; C2H5I→C2H4 + HI (3), k
3 = 1.7 × 1013 exp(−26680 KT) s−1; H + HI→H2 + I (4), k
4 = 7.9 × 10−11 exp(−330 KT) cm3 s−1 [D. L. Baulch et al., J. Phys. Chem. Ref. Data 10(Suppl. 1) (1981) 1]; C2H5I + H→C2H5 + HI (5), k
5 = 7.0 × 10−9 exp(−3940 KT) cm3 s−1. The latter bimolecular abstraction step turned out crucial for an adaquate d escription of the hydrogen atom concentration-time profiles in the above mentioned temperature and pressure range for initial concentrations [C2H5I]0 > 2 × 1013 cm−3 corresponding to mole fractions > 1 ppm.
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Affiliation(s)
- Tobias Bentz
- Karlsruher Institut für Technologie (KIT), Institut für Physikalische Chemie, Karlsruhe, Deutschland
| | - Milan Szőri
- University of Szeged, Dept. of Chemical Informatics, Szeged 6725, Ungarn
| | - Béla Viskolcz
- University of Szeged, Dept. of Chemical Informatics, Szeged 6725, Ungarn
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Altarawneh M, Al-Muhtaseb AH, Dlugogorski BZ, Kennedy EM, Mackie JC. Rate constants for hydrogen abstraction reactions by the hydroperoxyl radical from methanol, ethenol, acetaldehyde, toluene, and phenol. J Comput Chem 2011; 32:1725-33. [DOI: 10.1002/jcc.21756] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2010] [Revised: 12/20/2010] [Accepted: 12/23/2010] [Indexed: 11/08/2022]
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Abstract
Abstract
The reactions of hydrogen atoms with phenyl radicals, H + C6H5 → products (1), and with benzene, H + C6H6 → products (2), have been studied behind reflected shock waves in the temperature range 1200–1350 K with argon as the bath gas. H-atom resonance absorption spectrometry at 121.6 nm was used as detection technique. Hydrogen atoms and phenyl radicals were produced by thermal decomposition of C2H5I and C6H5I, respectively. Low initial concentrations (~1012–1015 cm-3) were employed to suppress consecutive bimolecular reactions as far as possible.The rate coefficients were determined from fits of the H atom concentration-time profiles in terms of a small mechanism. For reaction (1), a temperature-independent rate coefficient k
1
= 1.3×10–10 cm3 s–1 was obtained at pressures around 1.3 bar. For the rate coefficient of reaction (2), the temperature dependence can be expressed as k
2(T) = 5.8×10–10 exp(–8107 K/T) cm3 s–1, and a pressure dependence was not observed between 1.3 and 4.3 bar. The uncertainties of k
1 and k
2 were estimated to be ±40%.
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Fernandes RX, Fittschen C, Hippler H. Kinetic investigations of the unimolecular decomposition of dimethylether behind shock waves. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11144-009-5505-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Bentz T, Striebel F, Olzmann M. Shock-tube study of the thermal decomposition of CH3CHO and CH3CHO + H reaction. J Phys Chem A 2008; 112:6120-4. [PMID: 18547039 DOI: 10.1021/jp802030z] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The thermal decomposition of acetaldehyde, CH3CHO + M --> CH3 + HCO + M (eq 1), and the reaction CH3CHO + H --> products (eq 6) have been studied behind reflected shock waves with argon as the bath gas and using H-atom resonance absorption spectrometry as the detection technique. To suppress consecutive bimolecular reactions, the initial concentrations were kept low (approximately 10(13) cm(-3)). Reaction was investigated at temperatures ranging from 1250 to 1650 K at pressures between 1 and 5 bar. The rate coefficients were determined from the initial slope of the hydrogen profile via k1 = [CH3CHO]0(-1) x d[H]/dt, and the temperature dependences observed can be expressed by the following Arrhenius equations: k1(T, 1.4 bar) = 2.9 x 10(14) exp(-38 120 K/T) s(-1), k1(T, 2.9 bar) = 2.8 x 10(14) exp(-37 170 K/T) s(-1), and k1(T, 4.5 bar) = 1.1 x 10(14) exp(-35 150 K/T) s(-1). Reaction was studied with C2H5I as the H-atom precursor under pseudo-first-order conditions with respect to CH3CHO in the temperature range 1040-1240 K at a pressure of 1.4 bar. For the temperature dependence of the rate coefficient the following Arrhenius equation was obtained: k6(T) = 2.6 x 10(-10) exp(-3470 K/T) cm(3) s(-1). Combining our results with low-temperature data published by other authors, we recommend the following expression for the temperature range 300-2000 K: k6(T) = 6.6 x 10(-18) (T/K) (2.15) exp(-800 K/T) cm(3) s(-1). The uncertainties of the rate coefficients k1 and k6 were estimated to be +/-30%.
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Affiliation(s)
- Tobias Bentz
- Institut für Physikalische Chemie, Universität Karlsruhe (TH), Kaiserstrasse 12, 76128 Karlsruhe, Germany
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Friedrichs G, Colberg M, Dammeier J, Bentz T, Olzmann M. HCO formation in the thermal unimolecular decomposition of glyoxal: rotational and weak collision effects. Phys Chem Chem Phys 2008; 10:6520-33. [DOI: 10.1039/b809992h] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bentz T, Giri BR, Hippler H, Olzmann M, Striebel F, Szöri M. Reaction of Hydrogen Atoms with Propyne at High Temperatures: An Experimental and Theoretical Study. J Phys Chem A 2007; 111:3812-8. [PMID: 17388398 DOI: 10.1021/jp070833c] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The kinetics of the reaction of hydrogen atoms with propyne (pC3H4) was experimentally studied in a shock tube at temperatures ranging from 1200 to 1400 K and pressures between 1.3 and 4.0 bar with Ar as the bath gas. The hydrogen atoms (initial mole fraction 0.5-2.0 ppm) were produced by pyrolysis of C2H5I and monitored by atomic resonance absorption spectrometry under pseudo-first-order conditions with respect to propyne (initial mole fraction 5-20 ppm). From the hydrogen atom time profiles, overall rate coefficients k(ov) identical with -([pC3H4][H])(-1) x d[H]/dt for the reaction H + pC3H4 --> products ( not equal H) were deduced; the following temperature dependence was obtained: kov = 1.2 x 10(-10) exp(-2270 K/T) cm(3) s(-1) with an estimated uncertainty of +/-20%. A pressure dependence was not observed. The results are analyzed in terms of statistical rate theory with molecular and transition state data from quantum chemical calculations. Geometries were optimized using density functional theory at the B3LYP/6-31G(d) level, and single-point energies were computed at the QCISD(T)/cc-pVTZ level of theory. It is confirmed that the reaction proceeds via an addition-elimination mechanism to yield C2H2 + CH3 and via a parallel direct abstraction to give C3H3 + H2. Furthermore, it is shown that a hydrogen atom catalyzed isomerization channel to allene (aC3H4), H + pC3H4 --> aC3H4 + H, is also important. Kinetic parameters to describe the channel branching of these reactions are deduced.
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Affiliation(s)
- Tobias Bentz
- Institut für Physikalische Chemie, Universität Karlsruhe (TH), Kaiserstr. 12, 76128 Karlsruhe, Germany
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Yahyaoui M, Djebaïli-Chaumeix N, Dagaut P, Paillard CE, Heyberger B, Pengloan G. Ignition and oxidation of 1-hexene/toluene mixtures in a shock tube and a jet-stirred reactor: Experimental and kinetic modeling study. INT J CHEM KINET 2007. [DOI: 10.1002/kin.20265] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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