Performance and Emission Behavior of a Spark-Ignition Engine Fueled with Gasoline Blended with N-((5-chloropyridin-2-yl)carbamothioyl)furan-2-carboxamide

This study provides the first experimental evaluation of a benzoylthiourea derivative, CPFC: N-((5-chloropyridin-2-yl) carbamothioyl)furan-2-carboxamide, as a combustion-enhancing additive in terms of engine performance and emission characteristics in gasoline engines. The research investigates how CPFC affects the performance and emissions of a single-cylinder, four-stroke gasoline engine under incremental loads of 0%, 25%, 50%, 75%, and 100%. Test fuels comprised pure gasoline, a dichloromethane−ethanol (DCM–EtOH) blend, and CPFC-enhanced blends at 50 ppm, 100 ppm, and 200 ppm concentrations. Among the tested fuels, the 100 ppm CPFC blend exhibited the most balanced combustion, with λ values hovering near stoichiometric levels (1.04 at 0% load to 1.056 at 50% load). Compared with neat gasoline, the CPFC formulations achieved up to an 87.3% reduction in CO emissions (5.02% to 0.636%) and a 70.4% reduction in HC emissions (from 159 ppm to 47 ppm) at 50% load. Although CO 2 emissions increased slightly peaking at 13.308% for the 100 ppm blend at full load, this trend reflects enhanced combustion efficiency; however, NO x emissions reached 2000 ppm at higher loads. While the 50 ppm and 200 ppm variants showed promising outcomes under certain conditions, they were less effective at maintaining a stoichiometric balance at lower loads. Overall, these findings highlight that CPFC enhances combustion stability and reduces incomplete-combustion by-products more effectively than conventional additives, offering a new pathway for efficient and cleaner gasoline combustion.