Isothermal kinetics approach to investigating the oxidation process of red phosphorus in air

The isothermal oxidation process of red phosphorus (RP) was investigated by thermogravimetric analysis in the temperature range of 320–480 °C. The model-free, model-fitting and reduced-time plot methods were used to research the oxidation kinetics of RP. According to the d α /d t − α and model-free curves in different temperatures, the oxidation temperatures are divided into two ranges: lower temperatures (320–380 °C) and higher temperatures (390–410 °C). The apparent activation energy and oxidation controlling mechanisms in different temperature ranges are obtained. Besides, the trend of the oxidation rate with mass loss or temperature ranges is discussed.