Liquid Fuel Production by Co-pyrolysis of Plastic Waste Mixture: Influence of Temperature

Abstract

The growing accumulation of the plastic waste poses serious challenges to environmental safety. Simultaneously, the rising global demand for fuel has intensified efforts to convert the plastic waste into various valuable products, such as fuel. Plastic is normally sulfur-free; therefore, it produces green fuel. Co-pyrolysis offers an environmentally friendly and effective disposal method for converting plastic waste mixture into valuable liquid fuels with a positive synergistic effect between various types of wastes. This study investigates the co-pyrolysis of polypropylene, polystyrene, and high-density polyethylene in an equal proportion of 1:1:1 by mass, with the temperature ranging from 350 to 470 °C. The results demonstrated a significant impact of temperature on the yield, fractional distribution and physiochemical properties of the liquid fuel product. Liquid fuel was characterized by using American Society for Testing and Materials (ASTM) standard test methods to evaluate its physicochemical properties, including calorific value, American Petroleum Institute (API) gravity, viscosity, and flash point. The characterization of fuel revealed that co-pyrolytic oils exhibited physiochemical properties either within or similar to the ASTM standard range of conventional kerosene fuel. Additionally, the highest liquid fuel yield of 95% was achieved at 470 °C. ASTM D86-23a distillation confirmed the maximum kerosene fraction of 49.5%, in the liquid fuel obtained at 470 °C.