TY - JOUR
T1 - Theoretical study of important phenylacetylene reactions in polycyclic aromatic hydrocarbon growth
AU - Mao, Qian
AU - Pratali Maffei, Luna
AU - Pitsch, Heinz
AU - Faravelli, Tiziano
N1 - Publisher Copyright:
© 2024
PY - 2024/3
Y1 - 2024/3
N2 - Phenylacetylene is of significance in polycyclic aromatic hydrocarbon (PAH) growth in combustion systems, especially as the key intermediate species in the hydrogen abstraction carbon addition sequence. The consumption of phenylacetylene via H-atom abstraction reactions forming ortho-C6H4C2H (o-C6H4C2H) radical and its subsequent reaction with carbon addition are important steps in PAH growth. Nevertheless, rate constants for H-atom abstraction reactions from phenylacetylene have not been explored theoretically in the literature. As regards carbon addition, besides acetylene, ethylene is also presented in large concentrations in e.g., ethylene and propene flames. However, its role in PAH growth has not been well addressed yet. In this study, the H-atom abstraction reactions from phenylacetylene aromatic ring sites (ortho-, meta-, para-) by both H atoms and OH radicals, and the subsequent C2H4 addition to o-C6H4C2H radical are accurately determined with electronic structure calculations. The main bimolecular product from the potential energy surface of the C2H4 addition to o-C6H4C2H is 2-ethynylstyrene + H, while naphthalene + H and 1-methyleneindene + H are preferred to form at high temperatures and low pressures. Rate constants are lumped with an automated master equation-based lumping approach and integrated into a recently developed chemical kinetic model. Updates of the phenylacetylene-related reactions are tested by ethylene and benzene copyrolysis in shock tube, and ethylene oxidation in laminar premixed and counterflow diffusion flames. Reaction flux analysis are additionally performed regarding the phenylacetylene consumption and naphthalene formation.
AB - Phenylacetylene is of significance in polycyclic aromatic hydrocarbon (PAH) growth in combustion systems, especially as the key intermediate species in the hydrogen abstraction carbon addition sequence. The consumption of phenylacetylene via H-atom abstraction reactions forming ortho-C6H4C2H (o-C6H4C2H) radical and its subsequent reaction with carbon addition are important steps in PAH growth. Nevertheless, rate constants for H-atom abstraction reactions from phenylacetylene have not been explored theoretically in the literature. As regards carbon addition, besides acetylene, ethylene is also presented in large concentrations in e.g., ethylene and propene flames. However, its role in PAH growth has not been well addressed yet. In this study, the H-atom abstraction reactions from phenylacetylene aromatic ring sites (ortho-, meta-, para-) by both H atoms and OH radicals, and the subsequent C2H4 addition to o-C6H4C2H radical are accurately determined with electronic structure calculations. The main bimolecular product from the potential energy surface of the C2H4 addition to o-C6H4C2H is 2-ethynylstyrene + H, while naphthalene + H and 1-methyleneindene + H are preferred to form at high temperatures and low pressures. Rate constants are lumped with an automated master equation-based lumping approach and integrated into a recently developed chemical kinetic model. Updates of the phenylacetylene-related reactions are tested by ethylene and benzene copyrolysis in shock tube, and ethylene oxidation in laminar premixed and counterflow diffusion flames. Reaction flux analysis are additionally performed regarding the phenylacetylene consumption and naphthalene formation.
KW - Chemical kinetics
KW - Ethylene
KW - H-atom abstraction
KW - Naphthalene
KW - Phenylacetylene
UR - http://www.scopus.com/inward/record.url?scp=85184205923&partnerID=8YFLogxK
U2 - 10.1016/j.combustflame.2024.113300
DO - 10.1016/j.combustflame.2024.113300
M3 - Article
AN - SCOPUS:85184205923
SN - 0010-2180
VL - 261
JO - Combustion and Flame
JF - Combustion and Flame
M1 - 113300
ER -