Thesis Abstract

Increasing scarcity of fossil resources, increasing demand for petroleum fuels as well as increasing detrimental effects of extracting and using fossil fuels suggests alternatives. Biodiesel is a renewable, environmentally friendly, socially acceptable, technologically feasible and economically viable alternative fuel for diesel engines.

This study investigates the comparative characterization of biodiesels produced by transesterification from Jatrpha curcas and Thevetia nerifolia seed oil using ratio 15, 16, and 17 of methanol and oil and base catalyst (NaOH), at temperature of 60oC.
The percentage oil and biodiesel yield and the physco-chemical properties (PH, specific gravity, viscosity and flash point) of the methyl ester biodiesels were determined. The values of the biodiesel properties obtained were compared with America (ASTM) and European (EN) biodiesel standard. The data was analyzed using Randomized Complete Block Design (RCBD).

The result of this study shows that reaction ratio 15 has the highest biodiesel yield of 91%, 82% and 70% from Jatropha, Thevetia and the mixture respectively. There is a significant difference in the biodiesel yield among the three oil sources. The flash point increases with increase in the specific gravity of the biodiesels. The highest and lowest viscosity value (mm2/s) of 6.44 and 1.2 was recorded for mixture (17) and Jatropha (17) respectively. The biodiesel with the highest and lowest viscosity value and the biodiesels from thevetia (16 and 17) do not meet the ASTM and EN specifications which ranges between 1.9-6.0 and 3.5-5.0 respectively. Others meet the ASTM Specification (Table 4 and 5). Finally, the result of this study shows that Jatropha curcas and Thevetia nerifolia are good potential sources of oil for biodiesel production

Thesis Overview