Abstract: The impacts of different pretreatment conditions on enzymolysis and fermentation performance of sugarcane bagasse(SCB) pretreated by NaOH were investigated by single factor analysis and orthogonal experimental design.The effects of specific surface area and lignin content on enzymolysis of SCB were further studied.The results showed that the pretreatment temperature,time and mass fraction of NaOH significantly affected the enzymolysis and fermentation efficiency of the pretreated SCB.The optimal conditions for NaOH pretreatment were mass fraction of NaOH 4.5%,11 h and 85℃.Under these conditions,the cellulose content of the pretreated SCB reached 56.46% and increased by 46.16% compared with the raw SCB. And the xylan and Klason lignin contents reached 20.30% and 5.79%,which decreased by 15.77% and 72.87%,respectively.The reducing sugar yield reached 0.69 g/g substrate after 36 h enzymolysis.The specific surface area of pretreated SCB significantly increased (the maximum value of 1.07 m²/g from 0.07 m²/g of the raw was obtained),while the lignin content decreased significantly.Both of them were beneficial for the enhancement of the enzymolysis and fermentation efficiency.It was found that when the specific surface area surpassed 0.30 m²/g,the initial enzymolysis rate and final efficiency could reach a balance.Besides,when the the lignin content was lower than 11%,the enzymolysis efficiency reached a balance.

Key words: NaOH pretreatment, sugarcane bagasse, enzymolysis and fermentation