Investigation on combustion of fire retardant board under different N2–O2 mixture gas atmospheres by using thermogravimetric analysis

By thermogravimetric analysis (TGA) and kinetic study, the thermal decomposition and combustion processes of a fire retardant board were investigated under different N2–O2 mixture gas atmospheres, with 20%, 15%, 10% and 5% oxygen, respectively. The samples were heated from 373 K to 1223 K with a constant heating rate of 30 K/min. The trend of the thermogravimetry (TG) curves and derivative thermogravimetry (DTG) curves were interpreted regarding the conversion yields and the reactivity of samples. There are nine reaction stages which are discernible easily from DTG curves for samples under different gas atmospheres. Each sample’s top value among maximum mass loss rates of all reaction stages appears during reaction 4 stage. The reaction orders and apparent activation energies of all samples during all reaction stages vary between 1.4 and 4.0 and between 7.358 kJ/mol and 535.555 kJ/mol.

Research highlights
► Fire-retardant wood residue product as samples.
► Thermogravimetric and kinetics analysis for four oxygen concentration.
► Thermogravimetry curves and derivative thermogravimetry curves for samples.
► Kinetics parameters for fire-retardant wood products in a fire disaster.