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Pyrolysis of acetone was investigated in a jet-stirred reactor coupled with on-line GC and GC–MS in the temperature range 700–1136 K at atmospheric pressure. Six species, namely 1-C4H8, iC4H8, nC4H10, iC4H10, C5H6 and C6H6, were newly identified and quantified. A kinetic mechanism involving 296 species and 1836 reactions, including subsets of acetone and 2-butanone, was developed with reasonable predictions against the experimental data. C–C bond cleavage releasing CH3CO and CH3 radicals is the chain-initiation and the most intensively promoting reaction for the consumption of acetone. Its high-pressure limit rate constant was recalculated as k1 = 1.12 × 106·T3.84·exp(−78.6 kcal mol−1/RT) at the CBS-QB3 level. Besides this step, H- and CH3-abstractions of acetone by CH3 radical, with the calculated high-pressure limit rate constant as k4 = 1.38·T3.49·exp(−8.58 kcal mol−1/RT) and k7 = 5.70·T3.96·exp(−41.7 kcal mol−1/RT), respectively, govern the major consumption routes of acetone. CH3 radicals contribute as the key species to the production of the major hydrocarbons such as CH4, C2H4 and C2H6, and minor branches to benzene and C2H5COCH3. Moreover, the present kinetic mechanism could predict fairly the mole fractions of the gas species in the high-temperature pyrolysis of acetone and the ignition delay times of acetone at different temperature and pressure region, which indicates the applicability of this model in a wide-range condition.

The major components of a real Chinese RP-3 aviation kerosene were measured as 64.15% alkanes, 18.48% cycloalkanes, 15.88% aromatics. The oxidation of real Chinese RP-3 aviation kerosene was investigated in a jet-stirred reactor (JSR) at atmospheric pressure, φ = 2.0, and temperatures ranging from 575 to 1100 K. Mole fraction profiles of 25 species were detected with online GC and GC/MS. Three components (3C) surrogate fuel was validated against the measured results, as well as a detailed kinetic reaction model involving 453 species and 2991 reactions, was validated against the oxidation data A negative temperature coefficient (NTC) behavior of intermediates except for methane (CH4) was observed, due to the low-temperature activity of alkanes. The bimodal curves were observed for light hydrocarbons (C2-C4) and aromatic species and oxygenate, in which the second one is generally larger than the first one for light hydrocarbons (C2-C4) and aromatic species, while oxygenates exhibit adverse tendencies. Rate-of-production (ROP) analysis reveals that 1,3,5-trimethyl cyclohexane (T135MCH) mostly generates XCH2D35MCH radicals by dehydrogenation reaction, isomerizes to CH3SXD35MCH radicals, and further convert to C3H6. N-propylbenzene (NPB) is mainly dehydrogenated to form A1CHCH2CH3 and A1CH2CHCH3 radicals, which further transform to styrene (C6H5C2H3). Sensitivity analysis demonstrates that the consumption of both T135MCH and NPB are promoted by H/OH/HO2 radicals at low temperatures. At a temperature higher than 900 K, an insufficient supply of H/OH/HO2 radicals may lead to a competing reaction between the three components. Within the temperature range of 600 to 800 K, n-dodecane is the most active component to produce H/OH/HO2 radicals to initiate the oxidation of NPB and T135MCH. These results could improve the understanding of the specific combustion process of RP-3 aviation kerosene, and help the establishment of RP-3 aviation kerosene surrogate fuel as well.

A detailed chemical reaction kinetic mechanism involving 1181 species and 6964 reactions was developed for the combustion of two-components (surrogate A) and three-components (surrogate B) surrogate fuels for JP-8 and RP-3. The low temperature oxidation characteristics of the two surrogate fuels were compared regarding the aspects of components difference, negative temperature coefficient (NTC), intermediates and products formation. The surrogate A consists of 77.0% n-decane (NC10H22) and 23.0% 1,3,5-trimethylbenzene (T135MB) by mole fraction. The composition of surrogate B is 66.2% n-dodecane (NC12H26), 15.8% n-propylbenzene (NPB or A1C3H7) and 18.0% 1,3,5-trimethylcyclohexane (T135MCH) by mole fraction. The initial reaction temperature, NTC temperature range and fuel depletion temperature of surrogate A are significantly lower than those of surrogate B. Surrogate A tends to produce more aromatics and oxygenates than surrogate B in terms of quantity and type. Acetaldehyde was observed in the oxidation of the two surrogate fuels, while methanol, ethanol, acrylaldehyde, 1-propanol, 2-propanol and acetone were only detected in surrogate A oxidation. According to ROP analysis, T135MB is consumed mainly by methyl abstraction reactions. However, consumption of NPB is dominated by decompositions on the propyl group. Sensitivity analysis indicates that the reactions H2O2(+M) OH + OH(+M) and HO2 + HO2 H2O2 + O2 are the most promoting and inhibiting reactions on T135MB and NPB consumption. Moreover, the present mechanism could reproduce the ignition delay times of JP-8 and RP-3 surrogates. As the merged mechanism could simulate the macro and micro characteristics of fuel and surrogate fuel reasonably, it will be helpful to deepen the understanding of combustion process of aviation fuels.