Optimization of the lipase-catalyzed irreversible transesterification of Pistacia chinensis Bunge seed oil for biodiesel production

Production of biodiesel, a mixture of alkyl esters of fatty acids, by a lipase-catalyzed irreversible transesterification of Pistacia chinensis Bunge seed oil using dialkyl carbonate as an acyl acceptor is studied. Response surface methodology (RSM) based on central composite design (CCD) was used to optimize five important reaction variables. A quadratic model was established to modify those variables for high biodiesel yield. From the analysis of variance (ANOVA), the most important variables in the experimental design response were the reaction time, temperature, the molar ratio of oil to diethyl carbonate, and the amount of water added. The biodiesel yield predicted by the model was 98.2% under the optimal conditions and the subsequent verification experiments gave the average biodiesel yield of 97.6% thus confirming the validity of the predicted model.