308 / 2018-07-31 20:20:37

Effect of Acetic Acid Pretreatment on Enzymatic Hydrolysis of Poplar

全体主题 > 生物质多联产

Poplar, one of the main afforestation tree species in China, possessed the advantages of fast growing, wide distribution and short rotation periodis. Meanwhile, the poplar with high cellulose content, low amounts of ash and extractives, moderate lignin and hemicellulose contents can be used for the production of alternative biofuels and chemicals. Due to the recalcitrance and the complex structure of the poplar, a pretreatment is needed that can break down the poplar structure and enhance the efficiency of enzymatic hydrolysis. Acetic acid pretreatment is a green process for increasing enzymatic hydrolysis efficiency and simultaneously exhibits effective formation of xylo-oligosaccharides. In this study, ball-milled poplar was subjected to acetic acid at various reaction temperatures and acid concentrations. Hydrolyzabilities of pretreated poplar by cellulases and xylanase were compared and the effect of surfactant on enzymatic hydrolysis was investigated. In addition, structural features of un-treated and pretreated poplar were characterized with modern analytic equipment including scanning electron microscopy(SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FT-IR). The lignin fractions of poplar were isolated and characterized for elucidating the effects of acetic acid pretreatment on lignin inhibiton in enzymatic hydrolysis. This work provides a theoretical basis for the effective conversion of poplar into fermentable sugars and xylo-oligosaccharides.