Alkaline potassium aluminum carbonate: A novel high-efficiency dry powder extinguishing agent with high heat-resistant

Alkaline potassium aluminum carbonate (KAl(OH)2CO3) has potential application as an active medium for dry powder fire extinguishing due to its special molecular structure. In this paper, the application of KAl(OH)2CO3 as a high-temperature resistant dry powder extinguishing agent is first discussed. Firstly, the pyrolysis kinetics of KAl(OH)2CO3 was explored using thermal analysis techniques, including model-free and model-fitting methods. The pyrolysis of KAl(OH)2CO3 can be divided into three stages, with E values of 357.7 and 244.8 kJ/mol for stage 1 and stage 3, respectively. Higher activation energy of KAl(OH)2CO3 (T5 wt%=550 K, Tmax=648 K) means that it will not be deactivated prematurely in the high-temperature region. Moreover, the fire-extinguishing performance of KAl(OH)2CO3 is much better than that of BC dry powder fire extinguishing agent, which can suppress n-heptane and aviation kerosene pool fires within 6.00 s and 7.21 s. The possible fire-extinguishing mechanism of KAl(OH)2CO3 is also proposed. Therefore, KAl(OH)2CO3 is expected to be a high-temperature resistant dry powder extinguishing agent, which solves the application of existing dry powder fire extinguishing agents in high-temperature areas such as aircraft engine compartments.