Study on the inhibitory effect and mechanism of perfluoro(2-methyl-3-pentanone) on the combustion of gasoline blended with biomass additives

Abstract

Perfluoro(2-methyl-3-pentanone) (C6F12O, Novec 1230) has been considered as an emerging alternative to halon fire extinguishing agents, but its inhibiting characteristics for different concentrations of gasoline blended with biomass ethanol is still unclear. A new kinetic mechanism containing 241 substances and 1346 radical reactions was developed to investigate the combustion characteristics of ethanol gasoline and the inhibition characteristics of C6F12O. Experiments and previous data was used to confirme the mechanism's reliability. The results show that increasing the volume fraction of ethanol increases the laminar burning velocity and decreases the flame temperature of the mixture. A similar inhibitory effect of C6F12O is observed for gasoline at different ethanol blending concentrations. For rich flames, the fluorinated substances produced by C6F12O reduce the intensity of the reaction by trapping free radicals (OH, H, etc.), thereby reducing flame temperature and laminar burning velocity. For lean flames, adding sub-inerting concentrations of C6F12O produces large amounts of CO, which is an essential intermediate in promoting R24: CO + OH <=> CO2 + H, resulting in increased reaction strength. Combustion intensity is significantly reduced as more C6F12O is added, as the trapping of free radicals by the inhibitor becomes dominant.