Pyrolysis and Combustion Kinetics of Disposable Surgical Face Mask Produced During Covid-19 Pandemic

In order to prevent the spread of Covid 19, most countries have made face masks compulsory. Millions of face mask are disposed of daily in the community. Therefore, the aim of the present paper is to study the thermo-chemical (pyrolysis and combustion) behavior of the face mask for its safe disposal. The kinetic parameter activation energy was calculated using both the model-based Coats–Redfern method and model-free methods (Flynn-Wall-Ozawa, Kissinger-Akihara-Sunose, and Starink) at four different heating rates (5, 10, 15, and 20 °C/min). Physical morphology with elemental analysis was performed using field-emission scanning electron microscopy and energy-dispersive X-rays. Results have shown that face masks decompose in the temperature range of 320–480 °C during pyrolysis with a maximum derivative weight loss of 2.5 %/°C. Combustion took place between 200 and 370 °C with a maximum derivative weight loss of 1.25 %/°C. The average activation energies calculated using model-free methods for pyrolysis and combustion were ~135 kJ/mol and ~65 kJ/mol, respectively. The leftover residue for both pyrolysis and combustion was in the range of 1.35 to 3.50 wt.%. In conclusion, thermo-chemical processes are a promising method for the safe disposal of face mask waste.