Performance evaluation of egunsi melon (Citrullus Colocynthis L.) seeds oil biodiesel

Abstract

Oil was extracted from egunsi melon seeds by solhtex extraction method and transesterified to methyl ester using sodium hydroxide as catalyst and methanol to oil molar ratio of 6:1 to give high biodiesel yield. The egunsi melon oil, methyl ester and a blend of 20% biodiesel and 80% diesel were characterized using the ASTM protocols and the properties measured are within the ASTM D6751 limits for biodiesel. Of particular importance is the flash point which makes it a safe fuel for handling and storage. Chromatographic analysis gave 62.36% linoleic, 12.23% oleic, 12.88% palmitic acids as the major constituents. By blending with 80% diesel fuel, the oleic and linoleic acids reduced by 6.46% and 34.72% respectively which will improve oxidation stability of the fuel since both are unsaturated. The fuel was tested in a single cylinder diesel engine and gave torque and power close to those of diesel fuel but the specific fuel consumption was 8% higher and consistent with the difference in their heating values.