Performance and Emission Analysis of Diesel Engine Fueled with Waste Polypropylene-Derived Biodiesel Blended with Diethyl Ether

To solve the dual environmental issues of plastic pollution and reliance on fossil fuels, this study investigates the pyrolysis of waste polypropylene (PP) plastic into alternative diesel fuel. To improve fuel performance, the refined pyrolytic oil from PP was combined with regular diesel and 5% diethyl ether (DEE). The following three blend ratios were developed and assessed for important fuel characteristics: viscosity, density, flash point, cetane number, and calorific value: B10-DEE5-D85, B20-DEE5-D75, and B30-DEE5-D65. In order to enhance cold-start performance and ignition quality, DEE was used as an oxygenated additive. A four-stroke, single-cylinder diesel engine was used to test these mixes in order to evaluate their emissions and brake thermal efficiency. According to the results, the B10-DEE5-D85 mix had the most balanced performance, reducing CO and CO₂ emissions significantly when compared to pure diesel, especially while operating at full load. However, as the amount of biodiesel grew, so did NOx and HC emissions, indicating that the blend ratios need to be further optimised. The usual disadvantages of biodiesel, including its decreased energy content and increased viscosity, were mitigated by the use of DEE. Overall, the study demonstrates the technological feasibility of utilising bio-diesel blends made from plastic in diesel engines, supporting circular waste management techniques and sustainable fuel development.