Utilization of local corn (Zea Mays) wastes for bioethanol production by separate hydrolysis and fermentation

Abstract

Maize is the second most-common crop globally. Thus, enormous maize cobs are generated annually from maize processing activities which could serve as a potential and non-edible source for biofuel production. The primary aim of this research was to assess the practicality of producing bioethanol from discarded maize cob through a distinct two-step process referred to as separate hydrolysis and co-fermentation. After a 72-hour fermentation period, the greatest ethanol yield of 66.23 ± 8.35 mL/kg was obtained. This was followed by 54.33 ± 7.27 35 mL/kg after 48 h, and 21.68 ± 2.97 35 mL/kg after 24 h. Importantly, all ethanol yields at different time points exhibited statistical significance at p < 0.05. Moreover, the study revealed a robust positive correlation (r = 0.99, p < 0.01) between glucose and Total reducing Sugars (TRS) yields, and negative correlations were observed between ethanol yield and glucose (r = -0.97, p < 0.05) as well as ethanol and TRS (r = -0.98, p < 0.05). The results indicate the potential of maize cob waste as a valuable resource for bioethanol production. Significant enhancements in operational processes are necessary to enhance the economic feasibility of producing ethanol from maize cobs. Nigeria's utilization of waste for biofuel production is bolstered by substantial policy and financial backing for renewable fuels. The economic viability of ethanol production from maize cobs relies heavily on its competitiveness relative to other waste treatment methods and the effectiveness of policy measures.