Optimization of process conditions using response surface methodology for the microwave-assisted transesterification of Jatropha oil with KOH impregnated CaO as catalyst

A transesterification reaction of Jatropha curcas oil with methanol in the presence of KOH impregnated CaO catalyst was performed in a simple continuous process. The process variables such as methanol/oil molar ratio (X-1), amount of catalyst (X-2) and total reaction time (X-3) were optimized through response surface methodology, using the Box-Behnken model. Within the range of the selected operating conditions, the optimal ratio of methanol to oil, amount of catalyst and total reaction time were found to be 8.42,3.17% and 67.9 min, respectively. The results showed that the amount of catalyst and total reaction time have significant effects on the transesterification reaction. For the product to be accepted as a biodiesel fuel, its purity must be above 96.5% of alkyl esters. Based on the optimum condition, the predicted biodiesel conversion was 97.6% while the actual experimental value was 97.1%. The above mentioned results demonstrated that the response surface methodology (RSM) based on Box-Behnken model can well predict the optimum condition for the biodiesel production. (C) 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.