基于量子化学计算的正己烷热解反应动力学模拟OA北大核心CSTPCD

To study the atmospheric pressure pyrolysis properties of n-hexane(n-C6H14),an n-hexane pyrolysis(NHP)model was proposed,which used the error propagation-based direct relation graph(DRGEP)simplification method and the B2PLYP/def2-tzvp method employing dispersion-corrected density-functional theory to obtain a model with 33 components and 134 primitive reactions in a simplified mechanism.The model was utilized to calculate the relative mole fractions of the major pyrolysis products of n-C6H14,ethylene(C2H4),propylene(C3H6)and butyne(C4H6),at different temperatures,and the reaction pathways were analyzed for the pyrolysis process of n-C6H14.The pyrolysis of n-C6H14 was tested using synchrotron radiation vacuum ultraviolet photoionization mass spectrometry(SVUV-PIMS)coupled with a jet-stirred reactor(JSR)at temperatures ranging from 673K to 1103K and pressures up to 1atm,and was analyzed in comparison with the NHP model.The results showed that the finger-forward factors for the two reactions,which were more important for promoting the generation of C2H4,were 6.01×1013s-1 and 2.18×1013s-1,respectively.n-C6H14 was mainly analyzed by the NHP model combined with the NHP model obtained from quantum chemical calculations in the temperature range of 673-1023K.The relative molar fractions of the main n-C6H14 pyrolysis products were predicted in terms of their relative molar fractions.Compared with the JetSurF 2.0 model,the maximum errors for C2H4 and C4H6 were reduced by 27.9%and 47.9%,respectively.The reaction path analysis indicated that the most dominant product during the pyrolysis of n-C6H14 was C2H4,which mainly originated from a series of β-breaks of the hexyl group.