Use of Microwave Irradiation in the Noncatalytic Esterification of C18 Fatty Acids

Abstract

The main objective of this work was to investigate the C18 fatty acids esterification under microwave irradiation. The effects of alcohol used (methanol or ethanol), temperature (150−225 °C), molar ratio of alcohol/fatty acid (3.5−20), and total microwave irradiation power on the noncatalytic reaction conversion were evaluated. The results showed conversion up to 60% in 60 min of reaction. The temperature presented a pronounced effect on the conversion, following an exponential dependence. The results for a distinct molar ratio of alcohol/fatty acid indicated that the increase of this parameter lead to a decrease on the reaction conversion. In general, the esterification reaction under microwave irradiation yielded similar results to those obtained with the conventional heating but with very fast heating rates.