Combustion and emission characteristics of aviation biofuel derived from coconut oil using the co-solvent method: toward eco-friendly micro jet engines

The growing demand for Sustainable Aviation Fuel (SAF) as a means to reduce CO 2 emissions has led to the exploration of various production methods, including biofuel synthesis from plant oils. This study examines the combustion characteristics and exhaust gas emissions of SAF produced from coconut oil using a co-solvent method. The co-solvent method enables efficient production of high-purity biofuels by combining acetone and alcohol with coconut oil, reducing the energy required for production and subsequently minimizing CO 2 emissions. Combustion tests were conducted using a micro jet engine with fuels comprising kerosene blended with fatty acid methyl ester (FAME) or fatty acid ethyl ester (FAEE). The tests evaluated various blending ratios (10–50%) and engine speeds, focusing on the analysis of specific fuel consumption (SFC), thermal efficiency, and exhaust gas emissions. Results indicated that, while FAME and FAEE blends exhibited higher SFC than kerosene due to lower heating values, they achieved comparable thermal efficiency, demonstrating potential as an alternative aviation fuel. Analysis of exhaust gas emissions revealed reduced hydrocarbon (HC) levels at higher biofuel blending ratios, though slight increases in carbon monoxide (CO) were observed. Nitric oxide (NO) emissions remained within acceptable ranges, with minimal environmental impact on carbon dioxide ( CO 2 ) emissions. These findings suggest that coconut oil-derived biofuels can serve as a feasible SAF option, though further research is needed to optimize engine performance and assess long-term environmental benefits.