Study of Parametric Effects and Kinetic Modeling of Trans-esterification Reaction for Biodiesel Synthesis

A kinetic study of KOH-catalyzed trans-esterification of sunflower oil with methanol is carried out. Overall transesterification reaction consists of three consecutive second-order reversible reaction steps. Effects of methanol-to-oil molar ratio (MR), reaction temperature and catalyst loading on fatty acid methyl esters (FAME), triglycerides (TG), diglycerides (DG) and monoglycerides (MG) are evaluated by using statistical approach of Taguchi method with L9 orthogonal array and analysis of variance (ANOVA). Orders of parametric effects on FAME, TG, DG and MG based on the relative contribution of the three parameters are presented. Catalyst loading is found to be a significant control parameter for FAME, TG and DG wherein insignificant parameter for MG. The temperature is insignificant for TG and DG reduction wherein it has an important influence on the minimization of MG. The combination of parameters which yielded ~95% of FAME with reasonable purity is 0.5 wt% catalyst loading, 50°C temperature and 7 MR.