Study On Lipase-Catalyzed Biodiesel Duction From Waste Cooking Oil

The kinetic model of lipase-catalyzed biodiesel production from waste cooking oil was study in this research paper. Candida sp.99-125lipase was used in this research as catalyst. In order to calculate the kinetic parameters in the kinetic model, Matlab software was used as tool. After the analysis of the reaction mechanism, three different kinetic models were developed based on the Michaelis-Menten model. By fitting the experimental data into the kinetic equations, the rate constants in the kinetic model could be estimated, and the most suitable kinetic model was determined, which showed that the key reaction steps in the reaction system were the esterification of free fatty acids and the hydrolysis of triglycerol. The transesterification steps of glycerides could be ignored.In order to verify the validity of the kinetic model, a series of experiments under different initial reaction conditions were conducted, and the experimental data and the calculated values were compared. The results showed that the kinetic model could stimulate the reaction results properly, and the agreements between the experimental data and the calculated values were high. Moreover, methanol step-wise strategy was investigated. The results showed the model could also successfully stimulate the results using methanol step-wise strategy. Meanwhile, a twelve-step method and a three-step method were compared, and the result showed that the three-step method was the better one.Finally, the kinetic model was used to design a multi-level continuous reactor. After analysis of the methanol concentration and reaction rate, the time of methanol addition was Oh,6h and18h. Based on the methanol addition time, the reaction time of each reactor was determined, and the flow rate was determined. An experiment was conducted to verify the design of reactors, and the results showed that the yield of fatty acid methyl ester could reach the expected value at the exit of each reactor level.