Reserch In Liquid Fuel Production From Biomass Energy Wood

Confronted with the energy shortages and environmental pollution, development of biofuel production from biomass energy wood has become an important strategy. Biomass energy wood is a promising renewable feedstock for biofuel production, and butanol has been viewed as a superior liquid biofuel than ethanol. However, the recalcitrance of the biomass makes it difficult to deconstruct by enzymes and microbials. So the biomass materials mus t be pretreated to deconstruct its complex structure to achieve the high sugar yield for butanol fermentation. This paper has reviewed the introduction of biomass energy wood and the research statue for the technologies of butanol production from biomass e nergy wood. The technical problem present in butanol production and the prospects of biobutanol production from biomass energy wood are also discussed.In this study, eucalyptus was used for the experimental material and the conditions of its pretreatment, enzymatic hydrolysis and butanol fermentation were optimized The results are as follows.The pretreatment of eucalyptus was optimized by the response surface design, and the acid concentration, liquid to solid ratio, time and temperature were investigated according to the xylose recovery, enzymatic hydrolysis of cellulose and total sugars. The results showed that the optimum conditions for the pretreatment were H2SO4 concentration 0.52%(w/w), temperature 168 oC, time 27 min, liquid to solid ratio 1:10. Under these conditions, xylose recovery could be achieved 87.58%. The effects of cellulase loading and time on the enzymatic hydrolysis of cellulose were also investigated, the optimum conditions were cellulase loading of 60 FPU/g biomass and the time for 36 h, then the enzymatic hydrolysis of cellulose was obtained to 90.82%, and the total sugars was as high as 95.16%.Clostridium beijerinckii NCIMB 8052 was taken as the original strain for butanol fermentation glucose, xylose or the mixture of the glucose and xylose were used for substrates. The optimal fermentation conditions were determined by the addition of 1.6% corn steep powder into the detoxified hydrolysate of the eucalyptus. In the batch fermentation, b utanol and the total solvents could reach 11.9 g/L and 15.7 g/L respectively. The fermentable sugars utilization rate was 91.2%, and the utilization rate of glucose and xylose were 95.4% and 87.1%, respectively.