Pyrolysis kinetic behavior of composite polypropylene-biomass solid fuels derived via co-hydrothermal carbonization process

A treatment method producing solid fuel from surgical face masks was developed to address the high cost of medical waste management and the environmental concerns of large-scale, hazardous waste dumping during the coronavirus 19 (COVID-19) pandemic. The fuel properties were investigated of solid fuel produced from surgical face masks (polypropylene material (PP)) and from PP mixed with biomass (composite PP-biomass) using a hydrothermal carbonization process (HTC), followed by pyrolysis using thermogravimetric analysis (TGA). The Coats-Redfern (CR) method was used to analyze the pyrolysis kinetics and thermodynamic parameters. The results demonstrated that the thermal decomposition of raw PP material was less stable than for its hydrochar and the fuel properties of hydrochar obtained from the PP material were substantially improved using an increased HTC temperature. The activation energy value of the raw composite PP-biomass material was higher than for its hydrochar. This research identified an option for a potentially environmental-friendly treatment method for PP-material and its utilization as solid fuel.