Authors: Rafiu Kayode.Olalere, Hongming Xu, Sheriff Lamidi, Y.O Bankole
Abstract: The growing demand for carbon-neutral transportation has intensified research into renewable oxygenated fuels capable of improving engine efficiency while reducing exhaust emissions. Among emerging biofuels, biomass-derived 2-methyltetrahydrofuran (MTHF) has attracted considerable attention because of its favourable physicochemical properties. Nevertheless, comprehensive experimental comparisons of neat MTHF with gasoline, 2-methylfuran (MF), and ethanol under identical direct-injection spark-ignition (DISI) engine operating conditions remain limited. This study experimentally investigates the combustion characteristics, engine performance, gaseous emissions, and particulate emissions of neat MTHF relative to commercial gasoline (ULG95), MF, and ethanol using a single-cylinder DISI engine. Experiments were conducted at a constant engine speed of 1500 rpm, stoichiometric operation (λ = 1), and engine loads ranging from 3.5 to 8.5 bar indicated mean effective pressure (IMEP). Ignition timing for each fuel was optimized using the maximum brake torque (MBT) criterion or knock-limited spark advance (KLSA). At 5.5 bar IMEP, MTHF generated peak in-cylinder pressures of about 10%, 15%, and 25% higher than MF, ethanol, and gasoline, respectively. Compared with MF and ethanol, MTHF reduced indicated specific fuel consumption by approximately 8% and 33%, while maintaining thermal efficiency comparable to gasoline. Furthermore, MTHF produced lower total hydrocarbon and particulate emissions than gasoline and MF, together with lower NOₓ emissions than MF. These findings demonstrate that MTHF is a promising renewable gasoline substitute capable of simultaneously enhancing combustion performance and reducing exhaust emissions in modern DISI engines.
DOI: http://doi.org/10.5281/zenodo.21637881
