Transesterification Reaction Kinetics of Jatropha Oil for Biodiesel Production

ABSTRACT

Biodiesel, defined as the monoalkyl esters of vegetable oils and animal fats, is becoming

prominent among alternatives to conventional petro-diesel due to economic, environmental

and social factors. Transesterification is the most preferred method of biodiesel production.

Knowledge of transesterification reaction kinetic enables prediction of the extent of the

chemical reaction (or the conversion) at any time under particular conditions. It is also

essential in the optimization of operating conditions in industrial applications and in the

design of reactors for biodiesel production. In this study, transesterification of jatropha oil

with methanol was carried out in a well mixed reactor at different agitation speeds (600-900

rpm) and temperatures (35-65 oC) using sodium hydroxide as a catalyst. The methanol to oil

molar ratio of 6:1 was used and catalyst loading was 0.5% weight of oil. Mass transfer

controlled state was assumed to be minimal using the above agitation speeds. A second order

kinetic model was used to determine the reaction rate constants. The goodness of fit

predicting the moles of methyl ester in the reaction products was determined by correlation

coefficient (R2) and least square curve fit. The forward reactions were the most important as

revealed by the rate constants.

Keywords: Transesterification; Kinetics; Jatropha Oil; Rate Constants; Biodiesel