Influential parameters affecting transesterification reaction in biodiesel synthesis : a review

Abstract EN

Herein, attention was focused on the effect of the most influential parameters affecting the transesterification reaction.

It has been reported that in order to avoid the harmful saponification reaction and declination of yield, amount of water in the feedstock/alcohol used should be kept at minimum.

In addition, to avoid such obstacles and also poisoning of catalyst used and formation of foams and gels, amount of free fatty acids present in the feedstock oil should be trivial.

Due to the reversibility of transesterification reaction, the molar ratio of alcohol to oil is usually held reasonably high to ensure excess alcohol is used.

In this regard, different arrangements are required for edible oils and non-edible oils.

In opting the right amount of the used base catalyst, it might be accepted as a rule of thump that as the content of the feedstock oil of free fatty acids increases, the amount should be increased.

Beyond a certain catalyst amount; however, that amount cannot be right anymore.

Conversely, while using an acidic catalyst, a high amount might give rise to the formation of an ether instead of the desirable ester.

In terms of the duration of transesterification reaction, the longer the duration is, the better the yield would be, although such a trend might result in the development of some detrimental reactions.

As the temperature of a transesterification reaction is boosted, the degree of phase separation is lowered while reaction rate constants and miscibility are increased.

This results in a shortened reaction duration.