An Updated Kinetic Mechanism for the Combustion Inhibition of 2-Bromo-3,3,3-trifluoropropene (2-BTP)

2-Bromo-3,3,3-trifluoropropene (2-BTP, CF3CBr=CH2) is a promising halogenated flame suppressant, but its effects on flame propagation depend strongly on the coupled bromine and hydrocarbon chemistry. In this study, an updated kinetic mechanism was developed to describe the effects of 2-BTP on CH4–air and C3H8–air flames. The revised mechanism contains 200 species and 1680 reactions, including the re-evaluation of 48 Br-related rate expressions, the addition of 70 reactions, and the supplementation of thermochemical data for selected 2-BTP decomposition products. The mechanism was evaluated against available laminar burning-velocity measurements over ranges of equivalence ratio and 2-BTP concentration at 298 K and 0.101 MPa. Under stoichiometric conditions with 1 vol.% 2-BTP, the predicted burning velocities were approximately 17.4 cm/s for CH4–air and 22.15 cm/s for C3H8–air, compared with experimental values of approximately 17.4 and 22.53 cm/s, respectively. The revised mechanism generally reproduced the measured burning-velocity trends and improved the agreement under several conditions relative to the previous mechanism. Equilibrium calculations showed that low 2-BTP concentrations could increase the adiabatic flame temperature under lean conditions, whereas higher concentrations generally decreased the temperature. Reaction-path and sensitivity analyses identified the competing inhibition and combustion-promoting pathways, and highlighted reactions requiring further kinetic evaluation. Overall, the revised mechanism provides an improved description of the effects of 2-BTP on light-hydrocarbon flames under the tested conditions.