Fire extinguishing properties of novel ferrocene/surfynol 465 dispersions

This paper reports a novel fire-extinguishing agent: an aqueous dispersion of fine ferrocene particles. In this study, the ferrocene-water-surfactant dispersions were prepared to optimize the gas-phase concentration of ferrocene, and their ability to extinguish heptane fires was examined. The fire-extinguishing efficiency was characterized by three parameters: the ferrocene concentration in the dispersion (0-175 ppm), the surfactant used, and the ferrocene particle size (d50=10.4, 11.4, 21.5, and 68.8 μm). The results indicated that (1) the ferrocene (d50=10.4 mm)-water-surfynol 465 dispersion is the most stable among the dispersions tested, (2) the ferrocene-water-surfynol 465 dispersions have an optimal value of ferrocene concentration regarding the extinguishing time, and (3) in the ferrocene particle size range of 10.4-21.5 μm, the minimum extinguishing time of the ferrocene-water-surfynol 465 dispersions is remarkably shorter (1.2 s) than those observed when using a conventional wet chemical agent (45 wt% aqueous solution of potassium carbonate, 12.9 s).