Optimization Study for Efficient and Cleaner Production of Waste-Derived Biodiesel Through Fuel Modification and Its Validation

The objective of this study is to produce Citrus aurantium biodiesel (CAB) from orange peels and determine the optimal quantities of CAB, water, and ethyl-hexyl nitrate (EHN) in diesel fuel for efficient and cleaner combustion. The CAB was subjected to steam refinement, followed by subsequent analysis using Fourier-transform infrared spectroscopy (FTIR) and physicochemical analysis. To improve performance efficiency and minimize environmental impact, response surface methodology was employed to determine the optimal combination of CAB, water, and EHN in diesel fuel. The findings of the fuel characteristics investigation indicate that the recovered CAB exhibits an identical chemical composition to that of conventional diesel fuel and can be posited to serve as a viable substitute fuel. The optimization results indicate that the coefficient of determination has significantly approached unity, while the margin of error remains consistently around 1%. The energy and environmental characteristics demonstrate a strong alignment with the predicted data, and the recommended proportions for CAB, water, and EHN are determined to be 24.17%, 11.85%, and 1.22%, respectively. The fuel mixture under examination demonstrates the potential to decrease fossil fuel usage by approximately 37%, while also lowering levels of hydrocarbons, carbon monoxide, and nitrogen oxides by 8.1%, 20.2%, and 8.3%, respectively, compared to conventional diesel fuel.