Enhancing diesel engine efficiency with waste cooking oil biodiesel and nano additives for sustainable fuel applications

This study investigates the effect of incorporating nano-additives Cerium oxide (CeO₂), Zinc oxide (ZnO), and Titanium oxide (TiO₂) at 25 ppm concentration into biodiesel derived from waste cooking oil, with the objective of improving diesel engine performance and reducing exhaust emissions. Experiments were carried out on a single-cylinder four-stroke diesel engine under varying load conditions. Among the tested blends, the B20 + TiO₂ (25 ppm) mixture exhibited a modest reduction in brake thermal efficiency (2.53%) and a slight increase in brake specific energy consumption (3.80%) compared to diesel fuel. However, significant emission improvements were achieved, with a reduction in CO (23.42%) and HC (24.78%) emissions, accompanied by a decrease in smoke opacity (12.37%). The findings highlight that TiO₂ nano-additive biodiesel blends offer a sustainable and environmentally viable alternative to conventional diesel. The study is constrained by its emphasis on a particular mixture of biodiesel and nano additives, perhaps limiting the generalisability to different combinations or concentrations. The study largely assesses engine performance and emissions under a singular operating condition, potentially neglecting differences in performance across varied loads or speeds.