Comparative study on pyrolysis characteristics, kinetics, volatile products and chemical reactions of novel superhydrophobic and oleophobic ultra-fine and ordinary dry powder extinguishing agent

Abstract

The pyrolysis characteristics, kinetics, volatile products, and chemical reactions of a novel potential alternative for halon extinguishing agent in aircraft namely superhydrophobic and oleophobic ultra-fine dry powder extinguishing agent (SHOU DPEA) and ordinary dry powder extinguishing agent (ODPEA) are studied in the present study. The results illustrate that the thermal degradation process of SHOU DPEA and ODPEA may be divided into two stages (threshold: α = 0.8) and three stages (thresholds: α = 0.1 and α = 0.7). Therein, both of stage 1 of SHOU DPEA and stage 2 of ODPEA can be considered as one-step reaction, which can be well predicted by the calculated kinetic parameters. Besides, the pyrolysis of SHOU DPEA is more favorable than that of ODPEA. The relative concentrations of SHOU DPEA and ODPEA pyrolytic products from most to least are CO>H2O>CH4 >C2H6 >CO2 and CO>CO2 >H2O, respectively. In addition, the chemical reactions occurring in the pyrolysis of SHOU DPEA and ODPEA are revealed.