Fatty acid methyl ester production from rainbow trout waste oil using microwave-assisted transesterification

The desirable oil content of Rainbow Trout waste makes it a valuable resource for the industrial -scale production of biodiesel. Limited research has been conducted regarding the utilization of microwave -assisted transesterification (MAT) as a cost-effective method for biodiesel production from this accessible resource. In this study, MAT was optimized in terms of reaction time (1-5 min), microwave power level (100-500 W), methanol/ oil molar ratio (3-15), and catalyst concentration (0.3-1.5%). The optimal condition was reaction time of 4 min, microwave power 300 W, molar ratio of 12, and catalyst concentration of 1.2%, ensuring utmost efficiency and purity. In addition, MAT was compared to ohmic-, ultrasonic probe-, ultrasonic bath-, and magnetic stirrerassisted transesterification techniques, assessing physicochemical properties, energy consumption, and thermal properties of produced methyl esters. The microwave, ohmic, and ultrasonic probe showed superior efficiency, briefest reaction time, and minimal pouring and cloudy values, respectively. Additionally, these techniques consumed only 5.3, 5.7, and 6.7 Wh/g, respectively, signifying the lowest energy usage. Conversely, magnetic stirrer and ultrasonic bath showed less desirable performance. Overall, MAT can be suggested as a novel and effective technique for enhancing efficiency, reducing reaction time, and decreasing energy consumption in the production of marine waste oil methyl esters.