Chapter 17 - Interesterification reaction of vegetable oil and alkyl acetate as an alternative route for glycerol-free biodiesel synthesis

Abstract

Commonly, biodiesel is produced via transesterification reaction using alcohol, which yields glycerol as a by-product. The existence of glycerol can reduce the economic value of biodiesel due to the expensive separation cost. Thus an alternative route of biodiesel synthesis using alkyl acetate as the acyl acceptor which is called interesterification reaction has been investigated in this work. The reaction produces triacetin as a by-product rather than glycerol. Triacetin is a good antiknocking additive in fuels. The common alkyl acetate used in the interesterification reaction are methyl and ethyl acetate. The reaction can be conducted in mild or in supercritical condition. This chapter revealed a case study of the interesterification reaction of Jatropha oil (Jatropha curcas L.) with methyl acetate employing sodium methoxide catalyst to produce biodiesel in mild condition. The interesterification reaction was conducted at 40°C–60°C for 8h. The effect of catalyst concentration (0.25% to 1% w/w oil) was studied. A kinetic study has also been accomplished. It was found that the interesterification reaction fitted a second-order reaction kinetic model. The values of the preexponential factor and energy activation were (A) of 7.23×10−15L/mol.min and 86,116.41J/mol, respectively.