This paper, written by researchers from Shandong University of Technology and others, discusses Microwave assisted esterification of acidified oil from waste cooking oil by CERP/PES catalytic membrane for biodiesel production. The paper is published in an important journal < Bioresource Technology >. IF：5.807

In recent years, the research work of microwave chemical instrument used in the synthesis of materials has become a hot direction of scientific research, which has been paid great attention to by many scholars!

The traditional heating and microwave assisted method for biodiesel production using cation ionexchangeresin particles (CERP)/PES catalytic membrane were comparatively studied to achieve economicand effective method for utilization of free fatty acids (FFAs) from waste cooking oil (WCO). Theoptimal esterification conditions of the two methods were investigated and the experimental resultsshowed that microwave irradiation exhibited a remarkable enhanced effect for esterification comparedwith that of traditional heating method. The FFAs conversion of microwave assisted esterification reached97.4% under the optimal conditions of reaction temperature 60 C, methanol/acidified oil mass ratio 2.0:1,catalytic membrane (annealed at 120 C) loading 3 g, microwave power 360Wand reaction time 90 min.The study results showed that it is a fast, easy and green way to produce biodiesel applying microwaveirradiation.

In the present investigation, biodiesel was prepared by esterification of acidified oil with methanol under microwave irradiation condition. Compared with traditional heating method, microwave assisted esterification needs less reaction time, lower reaction temperature, less energy and lower methanol additive. Thus, manufacturing biodiesel using microwave represents a fast, easy and effective route with advantages of a short reaction time, a low methanol/acidified oil mass ratio, an ease of operation, reduced energy consumption and all with lower production cost. Further experiments need to be done in the future to investigate the possibility of scale-up for industrial application.

As shown in Fig. 1, microwave assisted esterification (MAE) was carried out with a microwave accelerated reaction system (Beijing XiangHu Science and Technology Development Co. Ltd., XH-200A). The system is equipped with a reflux condenser, a magnetic stirrer and an infrared temperature measurement which allows continuous stirring and constant temperature control. A three-necked batch reactor (500 ml) was used for the microwave assisted reaction and a flask (250 ml) full of water was settled in the chamber to absorb microwave during each experiment. The basic reaction conditions were: acidified oil 20 g, reaction time 120 min, reaction temperature 65 _C, methanol/acidified oil mass ratio 2.0:1, catalytic membrane loading 3 g and microwave power 360 W.