Impact of temperature and reaction time on the conversion of polystyrene waste to pyrolytic oil and its diesel engine performance, emission, and lubricity characteristics

The focus of this research is to see how temperature and reaction time affect the yield and quality of liquid oil obtained by pyrolysis. In a small batch pyrolysis reactor, polystyrene waste was employed as a feedstock. This study also studied the performance and emission characteristics of liquid oil produced at optimal condition (PS100), and its tribological characteristics in diesel engine. The ideal temperature and reaction time were discovered to be 400 °C and 30 min, where the liquid oil yield was 92.94% by mass. PS100 had similar properties to commercial diesel. PS100 comprises 34.6% aromatics, 25.2% alkanes, and 4.3% alkenes. PS100 delivered superior performance than B10 diesel. The brake thermal efficiency, brake power, and brake torque were up by 15.5, 5.6, and 2.38%, respectively, while the brake-specific fuel consumption was down by 8.00%. PS100 emitted 97.06 and 17.3% more hydrocarbon and carbon dioxide than B10, respectively. Its poor exhaust gas emissions have proven a key stumbling block in its application in diesel engine. PS100 demonstrated 27.6% increase in coefficient of friction and 29.8% increase in lubricant contamination as compared to B10. Despite its low lubricity and emissions, PS100 has a lot of potential as a diesel engine alternative fuel.