Pretreatment method for production of bioethanol with lignocellulosic material

【Objective】 With the increasing concerns on energy crisis and environmental problems, the production of bioethanol from renewable and readily available lignocellulosic biomass has received considerable attention around all over the world. The pretreatment methods of lignocelluloses for bioethanol production are reviewed in this paper to provide the new progress and new ideas for the production of value added products from lignocellulosic materials.【Method】 The primary pretreatment methods of lignocelluloses from the literatures are discussed and their advantages and disadvantages are comparatively investigated.【Result and conclusion】 Because of the complex structure, the conversion of lignocelluose into bioethanol is inefficient due to the crystalline structure of cellulose. The degraded hemicelluloses and lignin in the hydrolyzates produced also cause inhibition in the subsequent fermentation stage and lead to a low bioethanol yield. To obtain a high overall bioethanol yield and achieve an economically feasible production process, the destruction of cellulose crystalline structure and the removal of lignin and hemicelluloses prior to fermentation has the potential to provide the effective bioethanol production. Therefore, many pretreatment methods are applied to destroy the crystalline structure of cellulose, improve the accessibility and hydrolysis efficiency of interior cellulosic macromolecules, and remove lignin and hemicelluloses as well as avoid the inhibitory degradation products.