Biodiesel production from mixture of mahua and simarouba oils with high free fatty acids

A suitable process comprising acid pretreatment followed by main base transesterification reaction was developed to produce biodiesel from mixture of Mahua (M) and Simarouba (S) oils with high free fatty acids (FFA). The acid pretreatment reduced the high FFAs of the mixture of oils to around 1% which were then transesterified with methanol and KOH as catalyst at a reaction temperature of 60 °C. A genetic algorithm coupled with artificial neural network (ANN-GA) model to obtain the best pretreatment process parameters for bringing down the FFA level of individual vegetable oils to around 1% was modified to include the wide range of oils and validated for mixtures of M and S oils. The quality of biodiesel produced was analyzed by gas chromatography (GC), which indicated above 90% ester conversion. The fuel properties of biodiesel were found to be comparable to diesel and were conforming to the latest biodiesel standards.