| The energy crisis has made the development of biomass energy mainstream.The use of waste renewable SCB to produce ethanol could alleviate the energy crisis.However,due to the natural resistance structure of SCB,it is necessary to employ effective pretreatment to degrade and convert SCB into bioethanol efficiently.In this study,combined sodium percarbonate and glycerol was used to pretreat waste SCB.The best pretreatment conditions and the degradation mechanism of SCB were explored.Finally,ethanol fermentation was performed.The main research results of this study are as follows:(1)The effects of combined sodium percarbonate and glycerol pretreatment were explored on SCB.The orthogonal experiments were used to optimize the pretreatment conditions.Results showed that the best pretreatment conditions were using 12% sodium percarbonate concentration to pretreat SCB at 121? for 40 min.Under these conditions,the glucan and xylan content reached 45.19% and 36.30%,respectively,and the lignin was only 7.48% with the lignin removal rate of 81.14%.Total enzymatic efficiency and total reducing sugar were 91.06% and 16.67 g/L,respectively.(2)Sodium percarbonate alone and glycerol alone pretreatment were conducted to compare with the combined pretreatment.The degradation mechanisms of different pretreated SCBs were also explored.The results showed that the combined pretreatment could significantly degrade lignin and expose more cellulose,which proved that the combined pretreatment was effective.(3)Separate hydrolysis and fermentation(SHF)and simultaneous saccharification and fermentation(SSF)were applied on pretreated SCB to produce ethanol.The yield of ethanol from SHF was 104.98 g/kg while that of SSF was only 78.33 g/kg,which was 74.61% of SHF.So SHF method was more effective in ethanol production.In this study,an effective pretreatment method was established to convert waste SCB to bio-ethanol.It demonstrated good prospect and potential value in bioenergy. |
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