Abstract
Plastic waste accumulation is a significant threat to the environment and humans. Pyrolysis is a promising method for recycling plastic waste since all of the yields are useful, reducing the associated environmental risks of plastic waste. Energy recovery from used plastic waste can help restore ecosystems by utilizing waste as fuel while addressing the environmental problem of plastic disposal. This study experimentally investigates the application of oil obtained by the pyrolysis of waste high-density polyethylene (HDPE) as a viable energy source for diesel engines, offering a unique solution to the issues of plastic waste and energy sustainability. The catalytic pyrolysis method was employed to convert used HDPE plastics into a fuel called used polymer pyrolysis oil (UPO). The UPO was blended at 20% and 40% on a volume basis with mineral diesel. The graphite nanoadditives of 50 and 100 ppm were doped to enhance the properties of the UPO20 blend. The results showed that UPO20n100 blends exhibited a 2.79% increase in brake thermal efficiency and an 11.6% reduction in specific fuel consumption compared to diesel. Utilizing the UPO20n100 blend as a diesel engine fuel resulted in reductions of hydrocarbon, carbon monoxide, and smoke emissions by 8.9%, 9.9%, and 8.9%, respectively, compared with diesel operation. These findings provide a pathway for reducing plastic pollution and reliance on fossil fuels, with significant implications for the development of sustainable energy solutions. Additionally, this study presents a novel application of graphite nanoadditives in fuel blends prepared from used plastics, highlighting their significant impact on enhancing engine efficiency and reducing emissions.