Author(s)

Ravindra Pogaku, Jegannathan Kenthorai Raman, Gujjula Ravikumar

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In this study, the activation energy and thermodynamic properties of immobilized enzyme catalysed transesterification reactions were evaluated based on the enzyme substrate transition theory. The activation energy for a enzyme catalysed biodiesel production system were found to be 4.25 (kcal/mole) for monoglyceride formation, 5.58(kcal/mole) for diglyceride formation and 5.50 (kcal/mole) for methyl ester formation respectively. The rate constants were found to be 3.2 × 10¹⁰(L/mol.sec) monoglyceride, 3.47 × 10⁹ (L/mol.sec) for diglyceride and 3.93 × 10⁹ (L/mol.sec) for methyl ester. Based on the present work and published literatures, the activation energy of enzyme-catalysed transesterification reactions were found to be lower than the chemical-catalysed and non-catalyzed transesterification reactions. The thermodynamic properties of immobilized enzyme-catalysed transesterification reaction were found to be Gibbs free energy (ΔG = –1.02 kcal/mol), enthalpy (ΔH = 544 cal/mol) and entropy (ΔS = 5.19 cal/Kmol).

Activation Energy; Thermodynamic Properties

R. Pogaku, J. Raman and G. Ravikumar, "Evaluation of Activation Energy and Thermodynamic Properties of Enzyme-Catalysed Transesterification Reactions," Advances in Chemical Engineering and Science, Vol. 2 No. 1, 2012, pp. 150-154. doi: 10.4236/aces.2012.21018.