Waste fish oil (WFO) esterification catalyzed by sulfonated activated carbon under ultrasound irradiation

Abstract

In the present research work, esterification reaction of waste fish oil (WFO) catalyzed by sulfonated activated carbon under ultrasound irradiation was studied. The application of this catalyst, in addition to the elimination of purification process, leads to the green biodiesel production. The influences of various operating variables such as catalyst loading (1–12 wt%), methanol to oil molar ratio (6–15), and ultrasonic power (100–400 W) on the esterification conversion have been investigated. Response surface methodology (RSM) based on Box–Behnken design (BBD) has been employed. 88% conversion for the esterification reaction has been obtained under the best conditions (i.e., catalyst loading of 11.4 wt%, ultrasonic power of 296.09 W, and methanol to oil molar ratio of 14.85). An accurate mathematical correlation has been developed for the prediction of the esterification conversion. 56% conversion for the esterification reaction has been obtained in the same operating conditions in the absence of ultrasound irradiation.