Moringa stenopetala seed oil as a potential feedstock for Biodiesel production in Ethiopia

Abstract

ABSTRACT In this work, Moringa stenopetala seed oil is evaluated for the first time as potential feedstock for Biodiesel. Transesterification of M.stenopetala seeds oil was carried out with methanol, ethanol and mixture of methanol & ethanol (ME) in 3:3 molar ratios and using KOH as a catalyst. The esters were characterized by various methods to evaluate their densities, viscosities, water & ash content, iodine values, acid numbers, cloud & pour points, gross heat of combustion and fatty acid composition to use it in diesel engines. The experimental results show that M.stenopetala seeds contain 45% of oil. The oil was found to contain high level of mono-unsaturated fatty acids (78%), while the saturated fatty acid amount to 22%. The dominant fatty acid is oleic (76%). When methanol and ethanol used in 3:3 molar ratio (ME), the amount of ethyl ester formed was 30% that of methyl ester. The most conspicuous property of biodiesels derived from M. stenopetala oil is the low kinematic viscosity of 3mm2 /s for mixed ester (ME) and 3.2mm2 /s for methyl ester at 40oC, which is among the lowest reported for a biodiesel fuel. The physicochemical properties of mixed ester ME (3:3) was better than that of pure M.stenopetala methyl ester. Therefore, the best choice to use as a fuel would be the mixture of Moringa ester (ME). Their blending with conventional diesel (B20) also studied. All of the determined physicochemical properties of M.stenopetala oil methyl ester and mixture of ester were found to comply with both the American ASTM D6751 and the European standard EN 14214. Biodiesel derived from M.stenopetala oils is an acceptable substitute for petrodiesel when compared to biodiesel fuels from other vegetable oils. Therefore, the major physicochemical properties of M.stenopetala seed oil make it an attractive alternative application to the existing feedstocks for biodiesel production in Ethiopia.