Optimizing two stage chemical Pretreatment for Enset ventricosum: A Response Surface Methodology Approach to Enhance Bioethanol Production Efficiency

Abstract

Abstract Background: Bioethanol, a promising alternative to fossil fuels, effectively mitigates CO2 emissions, reduces global warming, and helps combat urban pollution while promoting sustainable energy solutions. Therefore, the objective of this study is to optimize a two-stage chemical pretreatment for Enset ventricosum in order to enhance the efficiency of bioethanol production. Results: In the experiment, Enset biomass leaves were subjected to a two-stage treatment using a solution of 1% H2SO4 and 1% NaOH (acid-alkaline treatment). The acid-alkaline pretreatment yielded the highest bioethanol content of 5.2 mg/ml and sugar concentration of 6.2 mg/ml, whereas the untreated sample had a bioethanol concentration of 2.2 mg/ml and sugar concentration of 3.4 mg/ml. The analysis using Response Surface Methodology identified optimal synthesis parameters for the pretreatment. These included a biomass concentration of 19.9775%, a pH of 3.86387, a temperature of 32.5739 °C, and an incubation period of 71.0274 hr. These parameters led to a predicted bioethanol yield of 9.65332 mg/ml with a desirability score of 1.000. Further analysis using SEM revealed significant changes in the surface morphology of the pretreated biomass. Additionally, FTIR spectroscopy confirmed the presence of cellulose and hemicellulose in the feedstock. Conclusion: These findings demonstrate the potential of Enset ventricosum biomass as a sustainable feedstock for bioethanol production. The study also highlights the importance of two stage chemical Pretreatment and parameter optimization in enhancing bioethanol yield.