Laminar flame speed of lignocellulosic biomass-derived oxygenates and blends of gasoline/oxygenates

Oxygenates present in partially hydro processed lignocellulosic-biomass pyrolysis oil to be component of second generation bio-fuels have been examined for their compact on the laminar flame speed of gasoline. Experiments were performed in an elevated pressure combustion vessel designed around a concept of a premixed Bunsen flame. Laminar flame speed measurements were firstly conducted for neat oxygenate fuel (anisole, 4-methylanisole and ethylvalerate)/N₂/O₂ mixtures at conditions T = 423 K, P = 0.1 MPa and φ = 0.6–1.3. It has been observed that anisole has a higher flame speed compared to 4-methylanisole and ethylvalerate. Meanwhile, very similar values of flame speeds have been obtained for 4-mythlanisole and ethylvalerate fuels. To learn the potential effect of these oxygenates present in biofuels acting as drop-in additives on the petroleum-based gasoline fuel, a five components surrogate gasoline fuel (hexane, 2,3-dimethyl-2-butene, cyclohexane, isooctane, and toluene) was then proposed and validated by comparing its laminar flame speed with commercial gasoline. Laminar flame speeds measurements were finally performed for the blends mixed by the proposed surrogate gasoline and different percentage of oxygenates over a large working condition range including T = 400–473 K, φ = 0.6–1.3 and P = 0.1–0.8 MPa. The influence of studied oxygenates as additives on gasoline has been found to be negligible for values up to 10% (wt) which is insensitive to the variation of pressure and temperature.