A reactive molecular dynamics study on high-temperature pyrolysis mechanism of n-propylbenzene

N-propylbenzene (NPB) is a key fuel component. Understanding its pyrolysis at high temperatures is vital for aviation kerosene combustion analysis. In this work, the pyrolysis process of NPB at 2300-3500 K, density of 0.05-0.55 g/cm3 and 100 ps is studied. The pyrolysis rates and bond breaking energies of NPB, toluene, ethylbenzene and n-butylbenzene are compared. The kinetic modeling is also used to perform sensitivity analysis on the intermediates and key products during the pyrolysis process, aiming to determine which specific steps would have significant effects on the final product distribution of NPB pyrolysis. The combination studies of the molecular dynamics simulation and kinetic modeling provide a positive direction to comprehensively elucidate the pyrolysis process of n-propylbenzene. The consistency of the simulation results confirms the rationality of the idea. The apparent activation energy of NPB calculated by first-order reaction kinetics is 55.73 kcal/mol, which is consistent with the experimental results.