An experimental and modeling study on pyrolysis reaction kinetics of oxygenated biofuel blended with aviation kerosene RP-3

Blending the renewable oxygenated biofuels with conventional fossil fuels is one of the feasible approaches to achieve carbon-neutral in the aviation industry, while there is very limited research available on the fundamental reaction characteristics of blended fuels. The primary objective of the present study is to conduct experimental investigations on the pyrolysis and oxidative pyrolysis reaction kinetics of oxygenated biofuels blended with China aviation kerosene RP-3 and establish a kinetic model. Pyrolysis experiments were conducted in a flow reactor at atmospheric pressure and temperature of 1130 K for blended fuels (methyl butanoate blended with RP-3, and n-butanol with RP-3) to examine fuel reactivity and formation of critical intermediates. The introduction of alternative oxygenated biofuel to the conventional hydrocarbon fuel RP-3 leads to the generation of CO during the pyrolysis reactions, as well as the reduced formation of olefin products. Notably, the CO yield from pyrolysis reactions of the blended fuel is increasing almost linearly with the concentrations of added oxygenated biofuels. A Two-Step Reaction Scheme (TSRS) modeling approach was extended for describing the reaction kinetics of oxygenated biofuels. TSRS models for methyl butanoate and n-butanol were constructed and merged with the HyChem model of RP-3 to complete the blended fuel model. Results show that the blended model predicts well the evolution of key intermediates with time, demonstrating the applicability of the model based on the two-stage characteristics of high-temperature reaction kinetics for describing the pyrolysis reactions of oxygenated fuels and hydrocarbon fuels.