Furan is one of the smallest organic compounds with heterocycle ring. With this particular molecular structure, furan is considered as a highly toxic and carcinogenic combustion pollutant, and furan may contribute to the formation of oxygenated soot. In this work, furan formation pathways from 1,3-butadiene, trans-2-butene and cis-2-butene were comprehensively explored. The potential energy surfaces, reaction rate coefficients, and thermodynamics were calculated by quantum chemistry using high level of theories including the CCSD (T) and G3 methods. The proposed reaction pathways were then implemented into the AramcoMech 3.0 model uniformly or independently to examine the model performance with the experimental data. The oxidation experiments of 1,3-butadiene, trans-2-butene and cis-2-butene were performed in a jet stirred reactor (JSR) in the low temperature regime (500–830 K). The JSR is coupled with time-of-flight molecular beam mass spectrometry (ToF-MBMS) using synchrotron radiation as photon ionization source for species identification and quantification. Compared with experiments, both updated models (the independent and uniform model) showed better prediction of furan than the base AramcoMech 3.0 model, which highlighted the contribution of the proposed pathways. Reaction pathway analyses reveal that in the proposed reaction pathway, both reactions C4H6 + OH ⇌ S1–4 (H2C[dbnd]CH-ĊH–CH2OH, but‑1-en-3-yl-4-ol) and C4H6 + HO2 ⇌ C4H61–3OOH4 (H2C[dbnd]CH-ĊH–CH2OOH, but‑1-en-3-yl-4-peroxide) not only contribute to furan formation, but also to fuel consumption. Furthermore, the kinetic uncertainty from activation energy calculated by the CCSD series methods, CBS-ANPO, and G4 methods was evaluated for reaction C4H6 + HO2 ⇌ C4H61–3OOH4. Instead of developing a new kinetic model, this work aims at proposing and validating new reaction pathways to advance the understanding of furan formation chemistry in low temperature oxidation, and provide guidance for future model development.
|Original language||English (US)|
|Journal||Combustion and Flame|
|State||Published - Jun 11 2021|
Bibliographical noteKAUST Repository Item: Exported on 2021-06-22
Acknowledgements: This work was performed as part of the Cluster of Excellence “The Fuel Science Center'', which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy - Exzellenzcluster 2186 “The Fuel Science Center” ID: 390919832. The research reported in this paper was supported by funding from the King Abdullah University of Science and Technology (KAUST) and the Clean Combustion Research Center (CCRC). NH acknowledges support from the U.S. DOE, Office of Science, Office of Basic Energy Sciences. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC. a wholly owned subsidiary of Honeywell International, Inc. for the U.S. DOE National Nuclear Security Administration under contract DE-NA0003525. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. DOE under Contract No. DEAC02-05CH11231. This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the USDOE or the US Government.