Optimization of lipase-catalyzed biodiesel by isopropanolysis in a continuous packed-bed reactor using response surface methodology.
Isopropanolysis reactions were performed using triglycerides with immobilized lipase in a solvent-free environment. This study modeled the degree of isopropanolysis of soybean oil in a continuous packed-bed reactor when Novozym 435 was used as the biocatalyst. Response surface methodology (RSM) and three-level-three-factor Box-Behnken design were employed to evaluate the effects of synthesis parameters, reaction temperature ( degrees C), flow rate (mL/min) and substrate molar ratio of isopropanol to soybean oil, on the percentage molar conversion of biodiesel by transesterification. The results show that flow rate and temperature have a significant effect on the percentage of molar conversion. On the basis of ridge max analysis, the optimum conditions for synthesis were as follows: flow rate 0.1 mL/min, temperature 51.5 degrees C and substrate molar ratio 1:4.14. The predicted value was 76.62+/-1.52% and actual experimental value was 75.62+/-0.81% molar conversion. Moreover, continuous enzymatic process for seven days did not show any appreciable decrease in the percent of molar conversion (75%). This work demonstrates the applicability of lipase catalysis to prepare isopropyl esters by transesterification in solvent-free system with a continuous packed-bed reactor for industrial production.
Chang
Cheng
C
Biotechnology Center, National Chung Hsing University, Taichung 40227, Taiwan.
Chen
Jiann-Hwa
JH
Chang
Chieh-Ming J
CM
Wu
Tsung-Ta
TT
Shieh
Chwen-Jen
CJ
D019840:2-Propanol / Q000378:metabolism*; D000704:Analysis of Variance; D055162:Biocatalysis; D056804:Biofuels; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D003247:Conservation of Natural Resources; D004800:Enzymes, Immobilized; D004952:Esters / Q000378:metabolism; D005656:Fungal Proteins; D008049:Lipase / Q000378:metabolism*; D008954:Models, Biological; D015203:Reproducibility of Results; D012212:Rheology; D013696:Temperature
D056804:Biofuels; D004800:Enzymes, Immobilized; D004952:Esters; D005656:Fungal Proteins; C093667:Novozyme 435; D008049:Lipase; D019840:2-Propanol