Characterization and Optimization Study of Transesterification of Non-Edible Oil Using Response Surface Methodology

In this study, calcium oxide (CaO) derived from waste bone was utilized as a catalyst for the transesterification of Neem seed oil (NSO) with methanol. The catalyst was characterized by scanning electron microscope (SEM), Fourier transforms infrared spectroscopy(FTIR), X-ray diffractometer(XRD) and Thermogravometric/differential thermal analysis. The process was optimized using response surface methodology (RSM) in combination with central composite design (CCD) was carried out to ascertain the best performing states and to improve the methyl ester output. The response changes being improved were: catalyst, concentration, methanol to oil molar ratio, reaction temperature, reaction time and agitation speed. The transesterification process was optimized by response surface methodology (RSM) in combination with the central composite design approach. From the analysis of variance (ANOVA), it was observed that the most significant criterion on methyl ester produced from methanolysis of neem oil was methanol to oil molar ratio and agitation speed. The predicted=91.2% output was established in good agreement with the analytical value of 92.0%, with R-squared value: 0.9966, Adj.R-squared value: 0.9904 and predicted R-squared value: 0.9846. The best methyl ester yield of 92.0% was achieved at 4h reaction time, with 4wt. % of catalyst weight and methanol to oil molar ratio of 8:1