Fluorosilane-Modified Antireflash Sodium Bicarbonate Fire Extinguishing Agent with Advanced Hydrophobic and Oleophobic Properties

Abstract

The poor antireflash performance of NaHCO3 dry powder fire extinguishing agent in class B fire is the key problem that restricts its application in large oil fires. In this work, the NaHCO3 was surface modified by sol–gel method to introduce functional fluorosilane structure (named FSi-NaHCO3) and enhance the hydrophobic and oleophobic properties. The water contact angle (WCA) and oil contact angle (OCA) of FSi-NaHCO35 are 147.0° and 144.2°, respectively, which means that FSi-NaHCO35 has advanced hydrophobic and oleophobic properties. The hydrophobic and oleophobic ratio of FSi-NaHCO35 are 92.35% and 91.59%, respectively. Furthermore, FSi-NaHCO35 dry powder fire extinguishing agent can extinguish aviation kerosene and n-heptane oil pool fires in 0.15 and 0.18 s, respectively, which is shorter than that of NaHCO3 dry powder fire extinguishing agent. After the secondary ignition, using FSi-NaHCO35 as dry powder fire extinguishing agent, the fire temperature of the aviation kerosene oil is significantly lower, and the full reburning time of the aviation kerosene oil fire is significantly longer than that of NaHCO3 dry powder fire extinguishing agent, which means FSi-NaHCO35 obviously has antireflash performance in an aviation kerosene oil pool fire.