Inhibiting Acid Formation and Oxidation of Groundnut Oil Biodiesel Using Green Additives

Abstract

The engine performance of biodiesel had become a major concern. Improving the acid and oxidation stability of groundnut oil biodiesel (GOME), with various plant waste extracts, was carried out on in this study. Freshly prepared GOME was blended with onion extract (OE) and ginger extract (JE), at the rate of 100:1 parts per million, and stored at a temperature of 30±50C for 28 days. At the end of the experimental period, the acid content and oxidation value of the biodiesel treated with both natural additives, were lower when compared to the biodiesel with additives. It was observed that untreated GOME acid value increased from 1.37 - 2.23 mgKOH/g, the acid value of the GOME containing OE increased from 1.35 – 1.81 mgKOH/g, and the acid content of the GOME treated with JE increased from 1.34 – 1.94 mgKOH/g. Regarding the oxidation stability, it was observed that the un-amended GOME oxidative stability decreased from 3.14 h to 2.44 h, the GOME amended with OE additive declined from 5.37 to 4.57 h, while the GOME treated with JE additive decreased from 4.99 h to 4.21 h. The findings of this study had revealed that incorporating natural additives into GOME, yield biodiesel with better oxidation stability. It was also noted that the blended GOME met the ASTM approved recommendation for biodiesel; unlike the results recorded for the GOME that was untreated with the natural additives.