Chemical and physical properties of plastic fuel from high and low-density polyethylene waste produced by pyrolysis method

In this research, the pyrolysis of high and low-density polyethylene (HDPE and LDPE) plastic waste has been carried out at a temperature of 450-550 ℃ with a heating flow rate of 15 °C/min. The application of different temperatures is intended to determine the quality of the resulting fuel oil fraction so that the physical and chemical characteristics of the resulting liquid can be known. Parameters of the fuel oil quality were observed including density, viscosity, calorific value, and the amount of hydrocarbon compounds that is characterized using Gas Chromatography-Mass Spectrometry (GC-MS). As the results, this research showed the process of pyrolysis process at a temperature of 450 ℃ could not produce fuel oil, while at 550 ℃ it produced wax, so the analysis of the quality of the fuel oil was not carried out. LDPE fuel oil has a viscosity of 0.75-0.84 cP, a density of 0.750-0.764 g/ml, and a calorific value of 11,338-11,421 kcal/kg, while fuel oil from HDPE has a viscosity value of 0.631-0.765 cP, density 0.777-0.784 g/ml and calorific value 11,188-11,224 kcal/kg. The results of the GC-MS analysis show that the content of the gasoline fraction (C8-C12) for LDPE plastic waste is 60.6-81.3% and for HDPE plastic waste is 24.87 - 41.64%, while for the kerosene and diesel fraction (C13-C20) is 1.36-23.13% for LDPE plastic waste and 28.48 - 37.43% for HDPE plastic waste. The gasoline fraction (C5-C12) of LDPE and HDPE plastic waste showed more dominant results than the kerosene and diesel fraction. Therefore, LDPE and HDPE types of plastic waste can be produced into alternative fuel types of gasoline.