Modified biodiesel - Impact of CuO additives and EGR on engine performance and emissions

The present research investigates the impact of CuO nanoparticle addition to Waste Plastic Oil (WPO) B20 biodiesel blends on the performance, combustion, and emission characteristics of a diesel engine. Experiments were conducted using diesel, WPO(B20), and WPO(B20) infused with varying CuO nanoparticle concentrations (25, 50, 75, and 100 ppm). The results indicate that the brake thermal efficiency (BTE) improved with CuO addition, reaching a peak at WPO(B20CuO75), which exhibited a 7.7% increase compared to WPO(B20). Correspondingly, brake-specific fuel consumption (BSFC) decreased by 7.4% due to enhanced combustion efficiency facilitated by the catalytic effect of CuO. Emission characteristics showed a significant reduction in CO (33%) and HC (30%) for WPO(B20CuO75), highlighting improved oxidation and flame propagation. Smoke opacity also exhibited a 21% reduction, confirming the role of CuO in promoting complete combustion. However, NOx emissions increased by 26% at WPO(B20CuO100) due to higher combustion temperatures. While WPO(B20CuO100) exhibited some deterioration in efficiency and increased emissions due to nanoparticle agglomeration, the findings demonstrate that CuO nanoparticle inclusion, particularly at 75 ppm, significantly enhances the performance and emission profile of WPO-based biodiesel, making it a promising alternative fuel for diesel engines.