Effect of dewaxing on saccharification and ethanol production from different lignocellulosic biomass

Dewaxing effects on the pretreatment, saccharification and fermentation are rarely reported due to the low abundance of wax in lignocellulose. This study aimed to investigate the effect of wax removal on saccharification and ethanol yield from lignocellulose by using Rice straw (RS), Napier grass (NG), and sugarcane bagasse (SB). The wax contents of 0.56%, 1.7%, and 0.6% were obtained from RS, NG and SB after the wax extraction, respectively. The alkaline pretreatment was applied in combination with dewaxing to decipher the synergistic effect of these treatments. Dewaxing and alkaline pretreatment of lignocellulosic biomass showed changes in the plant compositions. Removal of wax from RS, NG and SB showed significant changes in the surface morphology and functional groups. A higher yield of sugars and ethanol was observed in dewaxed and alkaline pretreated samples. The ethanol yields of 75.4%, 89.85%, and 74% from RS, NG, and SB were obtained after fermentation, respectively.