Emissions characteristics of spark ignition engine operating on lower–higher molecular mass alcohol blended gasoline fuels

An experimental investigation of emissions characteristics of lower–higher molecular mass alcohol blended gasoline fuels is presented in this paper. The alcohol component of the blends consisted of methanol, ethanol, propanol, butanol and pentanol. Apparatuses used in the present study were a single cylinder spark ignition engine, a hydraulic dynamometer and an exhaust analyzer. The variables that were continuously measured include engine rotational speed (min−1), CO, CO2, HC and NO emissions. During variable load tests, the results indicate that CO and HC levels in the engine exhaust are reduced with the operation on alcohol gasoline blends. NO emissions with alcohol gasoline blends are higher than with gasoline.

► Characteristics of pure and high alcohol blended gasoline fuels.
► Measured variables are engine rotational speed (rpm), CO, CO2, HC and NO emissions.
► Emissions of CO and HC from the pure-high alcohol/gasoline blends were lower than those from gasoline.
► Emissions of NO from the pure-high alcohol/gasoline fuel blends were higher than those from gasoline.
► The comparative results of emissions indicate that addition of longer-chain alcohols cause higher emissions except CO.