Synthesis of biodiesel from waste recycled oil employing animal bone ash

In this work, physiochemical properties of the waste used oil (WUO) were carried out for its aptness for biodiesel production. Calcined Animal Bone was used as a bio-base catalyst for the biodiesel production. The produced biodiesel was characterized and the optimum biodiesel produced was determined via statistical analysis using regression analysis. This was with a view to adding value to the waste used oil (WUO) and finding environmentally friendly alternative to fossil fuel.

Waste used oil (WUO) was preheated and purified to clean oil via filtration, and the physiochemical and other parameters (cetane number, API, aniline point among others) the cleaned oil were determined using standard methods. The Calcined animal bone was characterized using FTIR, SEM, XRF, BET adsorption, and qualitative analysis. Biodiesel production was done via base catalyst trans- esterification while statistical analysis was done using Microsoft Excel 8.0.  In order to ascertain the quality of the biodiesel, the physicochemical properties were determined and the qualities were compared with ASTM D6751 and EN 14214.

Results showed that the refined WUO properties were in line with property of oil require for biodiesel production. The physicochemical characteristics of the WUO showed physical state of the oil to be liquid/dark brownish at 28oc,  viscosity 6.58 cP at 28 0C, acid value, 0.96 (mg KOH/g oil), FFA (% oleic acid), 0.48, iodine value, 152.00 (g I2/100 g oil), peroxide value, 5.1 milli-equivalent of peroxide/kg of oil among others. The derived catalyst showed high basic strength with Calcium oxide (87.63 wt.%) 0s the dominant element in the catalyst. Optimum biodiesel yield was obtained at run 5 with 98.52 (%wt./wt.) at reaction time of 30 min, catalyst amount of 2.0 (%wt.), reaction temperature of 100 0C, and ethanol-oil molar ratio of 4:1.  The produced biodiesel properties conformed to the recommended standard ASTM D6751 and EN 14214.

The study concluded that WUO could serve as feedstock for biodiesel production that is environmentally friendly and the derived catalyst could be used as a bio-base in catalytic industries.