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

Abstract

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 (R2) 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 °C (MW-A) and 53.59 °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.

Keywords

• Transesterification
• Catfish oil
• Biodiesel
• Response surface methodology
• Microwave