Pretreatment Of Sugarcane Bagasse By Sodium Glyceroxide And Bioethanol Fermentation

As the major coproducts of the sugar industry,sugarcane bagasse(SCB)is an important renewable biomass resource to produce bioethanol.In order to convert the lignocellulose which is rich in SCB into fermentable reducing sugar efficiently,this study used self-made sodium glyceroxide as pretreatment reagent.The pretreament process can break down the natural recalcitrance of SCB and improve enzymatic efficiency and ethanol yield.In this study,firstly,SCB was pretreated by sodium glyceroxide,sodium methoxide and sodium ethoxide respectively.Analyses of the chemical compositions and enzymatic saccharification indicated that 5%(w/v)sodium glyceroxide pretreatment showed cellulose composition of 55% and xylan composition of 30.21%,while 72.80% of lignin was removed and the total reducing sugar yeild was 0.54 g/g.In this study,the characteristics of cellulase and its synergistic effect were explored by orthogonal test for the purpose of improving the utilization ratio of enzyme and enzymatic efficiency.The orthogonal experiment of the sodium glyceroxide pretreatment showed that,under the optimal conditions C1(6% of sodium glyceroxide,120 °C,50 min),which was based on the total reducing sugar concentration,contents of cellulose reached 56.48%,the total reducing sugar yield was 0.56 g/g,and the total reducing sugar concentration was 19.81 g/L.Under the optimal conditions C2(5% of sodium glyceroxide,120 °C,50 min),which was based on the total reducing sugar yield,the contents of cellulose reached 58.57%,the total reducing sugar yield was 0.59 g/g,and the total reducing sugar concentration was19.92 g/L.Besides,this study explained the physical and chemical feature of the pretreated SCB by scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD).The performance of fermentation of pretreated SCB was assessed by simultaneous saccharification and fermentation(SSF)and separate hydrolysis and fermentation(SHF)respectively.As the results shown,compared with the unpretreated SCB,the bioethanol yield of the SCB which were pretreated by the two optimal conditions C1 and C2 were increased by 84.01%.