Bioethanol Production Potentials of Corn Cob, Waste Office Paper and Leaf of Thaumatococcus daniellii

Aims: Lignocelluloses-based waste materials are prospective and renewable feedstocks for bioethanol production. Despite their widespread availability, little attention has been paid to their utilization as fermentation feedstocks for bioethanol production especially in developing countries like Nigeria. In this study, three lignocelluloses-based wastes: corn cobs, office paper waste, and Thaumatococcus daniellii leaves, commonly generated in Southwestern Nigeria were evaluated as fermentation feedstocks for bioethanol production.

Study Design: The study was a laboratory based experimental study which involved chemical hydrolysis and microbiological fermentation.

Place and Duration of Study: Department of Environmental Health Sciences, Faculty of Public Health, University of Ibadan, Ibadan, Nigeria, between July 2014 and December 2014.

Methodology: Separate hydrolysis and fermentation method was adopted for the study. Hydrolysis of the feedstocks was carried out at H2SO4 concentration of 6 M, 9 M and 13 M at 100°C for 60 min. Hydrolysates obtained were fermented at 30°C for 72 hours using Saccharomyces cerevisiae.

Results: Reducing sugar yields in the hydrolysates ranged from 51.5 – 27.3%, with highest yields from all the feedstocks obtained at 9M treatment, suggesting that 9M is the optimal concentration of H2SO4 for hydrolysis of the tested feedstocks. Highest ethanol yields of 20.2, 16.8 and 15.9 g/L were obtained at 48-hour fermentation period from waste office paper, corn cob and leaves of Thaumatococcus daniellii, respectively.

Conclusion: The results thus indicate that 48 hours is the optimal fermentation period for the feedstocks using Saccharomyces cerevisiae. The study has demonstrated that ethanol could be produced from the paper, corncobs and leaves of Thaumatococcus daniellii leaves with maximum yield obtained from office paper waste.