Optimization of microwave-assisted biodiesel production from waste catfish using response surface methodology

In the present study, response surface methodology involving central composite design was applied to optimize reaction parameters of biodiesel production from Tra (Pangasius hypophthalmus) and Basa (Pangasius bocourti) catfish oil during the microwave-assisted single-step transesterification process. Second-order polynomial models of the microwave-assisted method with acetone (MW-A) and isopropanol (MW-I) co-solvent were used to predict the biodiesel yield and the coefficient of determination (R-2) was found to be at 0.9926, and 0.9891, respectively. Research results demonstrated that isopropanol had similar effects to acetone on transesterification yields. The optimum biodiesel yield was calculated as 99.05% (MW-A) and 98.96% (MW-I) from the models with the following reaction conditions: methanol-to-oil molar ratio of 5.60 (MW-A) and 5.66 (MW-I), KOH concentration of 1.04 wt% (MW-A) and 1.00 wt% (MW-I), the reaction temperature of 53.20 degrees C (MW-A) and 53.59 degrees C (MW-I), the reaction time of 94.43 s (MW-A) and 93.27 s (MW-I), and co-solvent of 24.20 wt% (MW-A) and 22.73 wt% (MW-I). The results of biodiesel yield under optimal conditions have proved that the regression models agreed with the experimental data. Furthermore, the properties of catfish oil biodiesel produced under the optimum conditions were characterized and found to agree with the EN 14214 standard specifications. (c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

In this study, response surface methodology and central composite design were used to optimize the production of biodiesel from catfish oil through a microwave-assisted single-step transesterification process. The models predicted the biodiesel yield using acetone and isopropanol as co-solvents, and the results showed that isopropanol had similar effects to acetone. The optimal conditions for biodiesel production were determined, and the experimental results confirmed the accuracy of the regression models. The properties of catfish oil biodiesel produced under the optimum conditions met the EN 14214 standard specifications.