Potential Effect of Lemon Peel Oil with Novel Eco-Friendly and Biodegradable Emulsion in Un-Modified Diesel Engine

[Image: see text] The current research work is based on exploring a novel biological fuel source and renewable fuel offered by waste lemon fruit skin. Furthermore, bio-based multi-wall carbon nanotubes (BMWCNTs), emulsion, fossil diesel, and raw lemon peel oil were procured. The single-cylinder diesel engine was evaluated using these potential ingredients in terms of performance, combustion, and emission. Test engine results reveal that the presence of BMWCNT emulsion in the bio-fuel + blend + emulsion blend produced a lower (4.7%) brake thermal efficiency (BTE) and a higher (13.6%) brake-specific energy consumption (BSEC) at peak engine load conditions with diesel. The same test fuel blend possesses an equivalent heat release rate (HRR) and cylinder pressure trends to the diesel fuel blend due to an optimized air/fuel mixture and oxygen supply. Bio-fuel + blend + emulsion achieved step-down reductions of 7.83% carbon monoxide (CO) and 20.68% hydrocarbon (HC) emissions, as well as reductions of 27.7% nitrogen oxide (NO(x)) and 37.3% smoke emissions at peak engine load with diesel.