Properties of a new gasoline oxygenate blend component: 3-Hydroxybutyrate methyl ester produced from bacterial poly-3-hydroxybutyrate

3-Hydroxybutyrate methyl ester (HBME) was prepared from hydrolysis of bacterial poly-3-hydroxybutyrate (PHB) using methanol as an esterification agent in the presence of sulfuric acid. Physicochemical and fuel related properties of HBME were studied for the possibility of using HBME as a gasoline additive. When HBME was blended with 97# gasoline in volume ratios of 5%, 8.5%, 10%, 15% and 20%, respectively, it was found that HBME had similar or better properties as a fuel additive compared with ethanol in terms of oxygen content, dynamic viscosity, flash point and boiling point. The blending of HBME and gasoline showed only little difference compared with the 97# gasoline in terms of octane number (RON) and distillation ranges, especially for the HBME 8.5% and 10% blends, which demonstrated an over 93% combustion heat of gasoline with less than 5% reduction in RON.