Alkali Pretreatment for Bioethanol Fuel Production from Lignocellulosic Biomass

Bloethanol production from lignocellulosics using alkali pretreatment and enzymatic saccharification was proposed by our group. In this study, suitable alkali pretreatment conditions for bioethanol production from sugi, eucalyptus and bamboo were evaluated. As enzymatic digestibility increases with decreasing Mason lignin content, delignification occurs upon alkali pretreatment. However, it was suggested that complete removal of lignin in lignocellulosics is not necessary. Alkali pretreatment under severe conditions was required for lignin-rich softwood, such as sugi. On the other hand, low-lignin hardwood, such as eucalyptus, could be treated under mild conditions. Delignification of bamboo was higher than that of sugi but lower than that of eucalyptus. The glucose yield after saccharification of bamboo pulp was lower than that of sugi and eucalyptus. From the results of this study, eucalyptus was determined to be the best material among these lignocellulosics for bloethanol production using alkali pretreatment and enzymatic saccharification.