Ethanol Production From Hardwood Sawdust via Separate Hydrolysis and Simultaneous Saccharification Fermentation Methods

Abstract

The global demand for ethanol as a renewable fuel source has prompted the exploration of alternative feedstocks to mitigate concerns  related to food shortages, imbalances in the food chain, increased food prices, and indirect land use. This study investigates the feasibility of  producing ethanol from cellulose, specifically utilising hardwood sawdust. Two distinct methods, separate hydrolysis and fermentation (SHF)  and simultaneous saccharification and fermentation (SSF), were evaluated for their efficiency and environmental impact. Factors such  as sugar concentration, ethanol yield, theoretical ethanol yield, yield efficiencies, and sugar conversion were analysed to assess the  performance of each method. Findings show that 11.17 and 7.60 g of ethanol can be realised from 100 g of sawdust, following the SHF  and SSF procedures, respectively. The sugar concentration decreases with time during fermentation with Saccharomyces cerevisiae. The  choice between SHF and SSF methods for ethanol production depends on factors such as yield, cost-effectiveness, and environmental  considerations. Despite its longer time requirement in this study, SSF emerges as a more efficient and environmentally sustainable approach  compared to SHF, albeit at a higher cost.