Influence of esterification and neutralization in the production of biodiesel: a comparison study

The challenges of emission of greenhouse gases (GhG) have triggered researchers all over the world to come up with alternative fuel sources that reduce greenhouse gas emissions. One of such alternatives is Biodiesel production from Neem and Jatropha seed oils. However, the presence of Free Fatty Acids (FFA) in the oil obtained from these seeds reduces the yield of produced biodiesel. Two common methods proposed in previous literature to reduce the free fatty acids value are the Esterification and Neutralization methods. This study focused on comparing the esterification and neutralization method as a preliminary stage of biodiesel production from Neem seed and Jatropha seed oils, in an effort to advance biodiesel production in terms of yield from its process. The Neem and Jatropha seed oils were esterified with concentrated sulphuric acid and were tested for free fatty acids. Both seed oils were then refined via the degumming process, after which they were neutralized with sodium hydroxide. The study shows the neutralization method with a yield of 96% and 94% for Neem seed oil and Jatropha seed oil respectively to be more efficient than the Esterification method which produced a yield of 93.2% for Neem seed oil and 91.4% for Jatropha seed oil.