Optimization of NaOH-catalyzed steam pretreatment of empty fruit bunch

Biotechnology for Biofuels

Won-Il Choi²  Ji-Yeon Park²  Joon-Pyo Lee²  You-Kwan Oh²  Yong Chul Park³  Jun Seok Kim³  Jang Min Park¹  Chul Ho Kim¹  Jin-Suk Lee² 

[1] Applied Microbiology Research Center, Jeonbuk Branch Institute, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Jeongeup, Jeonbuk 580-185, South Korea

[2] Clean Fuel Department, Korea Institute of Energy Research, Jeongeup, Jeonbuk 580-185, South Korea

[3] Department of Chemical Engineering, Kyonggi University, Jeongeup, Jeonbuk 580-185, South Korea

关键词: Ethanol yields;    Simultaneous saccharification and fermentation;    Optimization;    Delignification;    Response surface methodology;    Steam pretreatment;    NaOH-catalyzed;    Empty fruit bunch;   

Others  :  794541
DOI  :  10.1186/1754-6834-6-170

 received in 2013-05-31, accepted in 2013-10-18,  发布年份 2013

【 摘 要 】

Background

Empty fruit bunch (EFB) has many advantages, including its abundance, the fact that it does not require collection, and its year-round availability as a feedstock for bioethanol production. But before the significant costs incurred in ethanol production from lignocellulosic biomass can be reduced, an efficient sugar fractionation technology has to be developed. To that end, in the present study, an NaOH-catalyzed steam pretreatment process was applied in order to produce ethanol from EFB more efficiently.

Results

The EFB pretreatment conditions were optimized by application of certain pretreatment variables such as, the NaOH concentrations in the soaking step and, in the steam step, the temperature and time. The optimal conditions were determined by response surface methodology (RSM) to be 3% NaOH for soaking and 160°C, 11 min 20 sec for steam pretreatment. Under these conditions, the overall glucan recovery and enzymatic digestibility were both high: the glucan and xylan yields were 93% and 78%, respectively, and the enzymatic digestibility was 88.8% for 72 h using 40 FPU/g glucan. After simultaneous saccharification and fermentation (SSF), the maximum ethanol yield and concentration were 0.88 and 29.4 g/l respectively.

Conclusions

Delignification (>85%) of EFB was an important factor in enzymatic hydrolysis using CTec2. NaOH-catalyzed steam pretreatment, which can remove lignin efficiently and requires only a short reaction time, was proven to be an effective pretreatment technology for EFB. The ethanol yield obtained by SSF, the key parameter determining the economics of ethanol, was 18% (w/w), equivalent to 88% of the theoretical maximum yield, which is a better result than have been reported in the relevant previous studies.

【 授权许可】

   
2013 Choi et al.; licensee BioMed Central Ltd.

【 图 表 】

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