Production of Biodiesel from Yellow Oleander (Thevetin peruviana (Pers. K Schum) Seed Oil

Abstract

The production of biodiesel from Thevetia peruviana seed oil using two different catalysts (NaOH and KOH) was evaluated. The Physical and chemical properties after extracting the seed oil were determined and the following results were obtained (density; 0.896g/cm3 , pH; 5.6, oil content; 32.5%, moisture content; 1.5%, specific gravity; 1.33, viscosity; 20mm2 /s, and refractive index; 1.48) and (Acid value; 0.3 mg of KOH/g, free fatty acid; 0.45%, iodine value; 38.5gI/100g, saponification value; was 75mg/KOH) respectively. Different catalysts were prepared by dissolving separately (0.18g. 0.20g and 0.21g) w% of NaOH and another 0.18g, 0.20, 0.21g w% of KOH pellets each in 10ml of methanol to produce concentrations of sodium and potassium methoxide respectively. Furthermore, Yellow Oleander Oil (YOO) was divided into 6 portions (25ml each) and poured into 6 different beakers (100ml) and separately placed on a magnetic stirrer. The amount of biodiesel produced at different concentrations of NaOH catalyst was 20.3ml, 20.1ml, and 22.3ml and the amount of biodiesel produced at different concentration of KOH were 24.2ml, 22.1ml, and 21.0ml. The conversion yield of the biodiesel catalysts was 81.2%, 80.4% and 89% for the NaOH catalyst and 96.8%, 88.4% and 84.0 for the KOH catalyst. The properties of the biodiesel such as flash point were 68℃, pour point was 3℃, cloud point was 7℃, cetane number was 98, the acid value was 0.5mg of KOH/g, density was g/cm3 , Iodine value was 3gI/100g, saponification value was 104, viscosity was 1.5mm2 s, the refractive index was 1.49. The results obtained from the study indicate that the physicochemical properties of the synthesized biodiesel are in agreement with the ASTM standard specifications. Both catalysts gave a considerable yield with KOH having a higher yield than NaOH in almost all the concentrations used. Thevetia peruviana can be considered a highly promising feedstock for biodiesel production.