Ethanol production from high dry matter corncob using fed-batch simultaneous saccharification and fermentation after combined pretreatment.
To obtain high concentration of ethanol from cellulose, corncob was pretreated with acid and alkali to remove non-cellulose components, and then subjected to simultaneous saccharification and fermentation (SSF). An ethanol concentration as high as 69.2 g/L was achieved with 19% dry matter (DM) using batch SSF, resulting in an 81.2% overall ethanol yield. A fed-batch process using a high solid concentration was also investigated. Fresh substrate was pretreated with dilute sulfuric acid-sodium hydroxide, and then added at different amounts during the first 24 h, to yield a final dry matter content of 25% (w/v). SSF conditions with cellulose loading of 22.8 FPU/g glucan, dry yeast (Saccharomyces cerevisiae) loading of 5 g/L and substrate supplementation every 4h yielded the highest ethanol concentration of 84.7 g/L after 96 h. This corresponded to a 79% overall ethanol yield.
Zhang
Mingjia
M
State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Wang
Fang
F
Su
Rongxin
R
Qi
Wei
W
He
Zhimin
Z
D000143:Acids / Q000737:chemistry; D000641:Ammonia / Q000737:chemistry; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D002241:Carbohydrates / Q000737:chemistry*; D004736:Energy-Generating Resources; D000431:Ethanol / Q000737:chemistry*; D005285:Fermentation; D005561:Formates / Q000737:chemistry; D006868:Hydrolysis; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D012972:Sodium Hydroxide / Q000737:chemistry; D013464:Sulfuric Acids / Q000737:chemistry*; D003313:Zea mays
D000143:Acids; D002241:Carbohydrates; D005561:Formates; D013464:Sulfuric Acids; C030544:formic acid; D000431:Ethanol; D012972:Sodium Hydroxide; D000641:Ammonia; C033158:sulfuric acid