The physicochemical properties of the waste used oil (WUO) were carried out for biodiesel production. The heterogenous catalyst (CAO based) used in this work was derived from waste seashell. The produced biodiesel was characterized and the optimum biodiesel produced was determined through statistical analysis. This was with a view to add value to the WUO and finding the solution to reduction of the excess carbon release to the environment. According to the results obtained, it showed that the refined WUO properties were in line with oil property requirement for biodiesel production. The physicochemical characteristics of the WUO showed physical state of the oil to be liquid/dark brownish at 28 oC, viscosity 6.58 cP at 28 oC, acid value, 0.96 (mg KOH/g oil), FFA (% oleic acid), 0.48, iodine value, 152.00 (g I2/100g oil), peroxide value, 5.1 milli-equivalent of peroxide/kg of oil among others. The derived catalyst showed high basic strength with potassium oxide (61.63 wt.%) as the dominant element in the catalyst. Optimum biodiesel yield was obtained at run 5 with 98.52 (%wt./wt.) at reaction time of 65 min, catalyst amount of 4.0 (%wt.), reaction temperature of 70 oC, and ethanol-oil molar ratio of 7:1. The produced biodiesel properties was compared with the recommended standard ASTM D6751 and EN 14214.
Keywords: Biodiesel, Oil Kernel, Renewable Energy, Waste Seashell, characterization of biodiesel, waste used oil
