Thermo-Chemical conversion of polyolefin-based facemask using bench-scale pyrolysis system

ABSTRACT

The generation of personal protective equipment (PPE) waste due to the impact of COVID has increased multi-fold globally. In this study, pyrolysis of polyolefin-based PPEs was carried out using a bench-scale reactor of 2 kg per batch capacity. Thermogravimetric (TGA) analysis of face masks was carried out to identify the optimal parameters for the pyrolysis process. Different combinations of catalysts (ZSM-5 and montmorillonite), catalyst to feed ratio (2.5% and 5%), experiment duration (2 h and 3 h), and process temperature (450°C and 510°C) were tested to determine the maximum yield of the pyrolysis oil. The oil and char obtained from the pyrolysis of PPEs were analyzed for its gross calorific value (GCV), elemental analysis (CHNS), and chemical composition. Based on the experiments conducted, the optimum pyrolysis temperature, catalyst, catalyst to feed ratio, and batch time for maximum oil yield (55.9% w/w) were determined to be 510°C, ZSM-5, 5%, and 2 hours, respectively. Oil was free of sulfur and had a calorific value of 43.7 MJ/kg, which is comparable to commercial diesel fuel and makes it a suitable alternative fuel for ships, boilers, and furnaces.

KEYWORDS:

• Pyrolysis
• ZSM-5
• face masks
• bench-scale
• oil
• char

Acknowledgement

The project was funded by Samudhyoga Waste Chakra Pvt. Ltd. and IIT Madras. We thank them for their financial support. The authors acknowledge thanks to the Srushti fertility hospital, Chennai, and IIT Madras hospital for providing the PPE wastes.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work was supported by the Samudhyoga Waste Chakra [INID:072021].