• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.326-332
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• 2012

Among the samples prepared by various pre-treatment methods, the one pretreated by dilute sulfuric acid showed the highest glucose yield in the enzymatic hydrolysis. Statistical analysis of enzymatic hydrolysis revealed that the glucose yield was in proportion to the enzyme dosage, the ratio of the pre-treated sample to the buffer solution, and the reaction time and that the effect of enzyme dosage was predominant in the experiment range. In addition, the glucose yield was estimated to be 76.1% at an optimal enzymatic hydrolysis condition. In a separate hydrolysis and fermentation (SHF), Saccharomyces cerevisiae converted over 80% of glucose from the enzymatic hydrolysis of pre-treated wasted corn stalk by dilute sulfuric acid to bioethanol with 37% of ethanol yield and 0.42 $g/L{\cdot}hr$ of productivity. In the simultaneous saccharification and fermentation (SSF), 59.5% of conversion from glucan to ethanol and 0.20 $g/L{\cdot}hr$ of productivity were achieved. In both SHF and SSF, approximately 88 g of bioethanol could be obtained from 1 kg of wasted corn stalk. The possible amount of bioethanol in Gangwon province were estimated to be 1.9 kiloton with the assumption of the 50% of collection ratio.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.3
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• pp.79-89
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• 2011

The wasted corn stalk from Gangwon province is composed of 44.6 % glucan, 19.0 % xylan, 23.8 % lignin, 4.5 % ash and 8.1 % others. Statistical analysis, full factorial design, revealed that temperature was the most influential factor in the dilute sulfuric acid pretreatment and that the influence of temperature on xylose yield was 3.5 and 3.2 times higher than those of treatment time and acid concentration, respectively. Temperature was also the most influential factor for glucose yield in the pretreatment but it was less than 5 % throughout the pretreatment. Although minor sugar yield was observed when microwave or ultrasonication was solely introduced as a pretreatment method, the complex method incorporating microwave or ultrasonication into dilute sulfuric acid pretreatment enhanced sugar yield significantly. In particular, xylose yield was doubled when microwave and dilute sulfuric acid treatment was sequentially applied. The optimization of pretreatment and enzymatic hydrolysis as well as the investigation on the complex pretreatment in detail are left for further study.