An aqueous emulsion of 2-BTP: Remarkable fire suppression synergy with superior resistance to reignition

An aqueous emulsion of 2-bromo-3,3,3-trifluoropropene (2-BTP), referred to as 2-BTP/W, was developed for fire extinguishing applications. It had overcome the immiscibility between 2-BTP and water by using an anionic surfactant. The results showed that a surfactant concentration of 4 % was preferred for achieving a stable, uniformly dispersed emulsion over an extended period. The emulsion displayed a narrow droplet size distribution, with 79 % of the population below 10 μm. Fire suppression performance of the emulsion was then evaluated. The shortest fire extinguishing time for the wood crib and n-heptane pool fires were 3.9 s and 0.8 s, respectively. These were achieved with minimum emulsion consumption of 193.5 mL and 21.3 mL, in conjunction with peak cooling rates of 210 °C/s and 325 °C/s. The synergistic factor ranged from 0.05 to 0.4, significantly lower than that of other reported synergistic agents. By combining rapid chemical inhibition with efficient physical cooling, the emulsion agent offers an enhanced fire suppression performance with reduced agent consumption.