Abstract
With increasing population, modernization, and industrialization, plastics usage is growing daily and results in vast plastic waste. Recycling these plastic wastes to hydrocarbon fuels is challenging due to their different chemical structures, long-chain polymeric compositions, and decomposition/thermal behavior. In the present manuscript, the pyrolysis of domestic plastic waste was carried out at 473 - 973 K in a fixed bed tubular reactor and compared with individual virgin plastics, i.e. HDPE (High-density polyethylene), LDPE (Low-density polyethylene), PP (Polypropylene), and their mixture of (virgin mixed plastic). The experiments were also performed using a low-cost catalyst (mineral clay) to maximize hydrocarbon fuels. At identified optimum operating conditions, the domestic plastic waste and mixed virgin plastics yielded 73.1 wt% and 81.6 wt% liquid hydrocarbons along with 16.9 wt% and 25.5 wt.% pyrolysis gas, respectively. The composition of liquid fuels was analyzed using FTIR and GC-MS in detail, revealing a wide variety of hydrocarbons disbursement in the range of C8–C20. In addition, fuel properties of liquid fuels such as viscosity, density, fire and flash point, pour point, and calorific value was analyzed according to ASTM methods and found to be satisfactory. Based on chemical composition and fuel properties, liquid fuels derived from domestic plastic wastes showed 78.05%, and 61.86 % similarity with diesel, and jet fuels respectively. Non-condensable gases, which mainly consist of ethane and propene with minor amounts of hydrogen and methane, have been identified to be ideal for spark-ignition engine (SI) engines. This study offers a unique technique for converting waste plastics into transportation jet fuel using an affordable catalyst.
Catalytic pyrolysis of plastic waste for the production of liquid fuels for engines
