Alkaline Deacetylation for Cellulosic Ethanol Production Using Potential Energy Crops

다국어 초록 (Multilingual Abstract)

Hemp (Cannabis sativa) and Kenaf (Hibiscus cannabinus) are similar in appearance, but hemp belonging to the genus Cannabis is grass-like, and kenaf belonging to the genus Hibiscus is hard like wood. Meanwhile, cellulosic hydrolysates with lignin structure contain specific and considerable amount of acetic acid. Acetic acid inhibits yeast fermentation, causing cytosolic oxidation and stresses. Therefore, optimizing cellulosic treatment process is necessary for a specific type of biomass considering acetic acid concentration. In present study, ethanol production yield was improved by performing deacetylation pretreatment in which only acetic acid was selectively removed by mild-alkaline before acid pretreatment. In addition, optimal condition was confirmed to minimize the loss of fermentable sugar. Finally, compositional analysis of the biomass and removal amount of acetic acid were comparatively analyzed. These results indicate that ethanol yield and productivity can be improved by removing acetic acid from hydrolysates through deacetylation process and suggest that acetic acid bypass strategy is absolutely necessary to efficiently utilize cellulosic biomass as a bio-based energy source.