Optimization of Some Fermentation Conditions for Bioethanol Production from Yam Peels (Dioscorea rotundata) Using Box-Behnken Design (BBD)

Abstract

Aim: The aim of this research was to optimize the production of bioethanol from a select second generation feedstock (yam peels). Methodology: Bioethanol was produced from yam peels using Box Behnken Design (BBD). The independent variables selected for optimization of bioethanol yield were; fermentation temperature (˚C), fermentation time (hours) and yeast concentration (%w/v). A set of 17 experiments were considered by design expert software. All experiments were run in triplicates. Test for bioethanol was carried out using acidified potassium dichromate method and absorbance was taken using a spectrophotometer at 600nm. Results: From the experiments carried out above, the optimum conditions under which the highest bioethanol (yield%) was produced were a fermentation temperature of 30̊C, yeast concentration of 5.50%w/v and fermentation time of 96hours under which a bioethanol yield of 45.79% was produced. Conclusion: Yam peels may therefore have the potentials to serve as substrates for bioethanol production rather than using food crops such as sugarcane juice and cassava flesh which may lead to food shortages and crisis especially is developing countries such as Nigeria.