Continuous alkaline pretreatment of Miscanthus sacchariflorus using a bench-scale single screw reactor

• Published in: Bioresource technology Vol. 181; pp. 338 - 344
• Main Authors: Cha, Young-Lok, Yang, Jungwoo, Park, Yuri, An, Gi Hong, Ahn, Jong-Woong, Moon, Youn-Ho, Yoon, Young-Mi, Yu, Gyeong-Dan, Choi, In-Hu
• Format: Journal Article
• Language: English
• Published: England 01.04.2015
• Subjects: Biomass; Bioreactors; Biotechnology - instrumentation; Biotechnology - methods; Carbohydrate Metabolism - drug effects; Cellulase - metabolism; Fermentation - drug effects; Hydrolysis; Poaceae - drug effects; Sodium Hydroxide - pharmacology; Miscanthus; Bioethanol; Continuous pretreatment; Alkaline pretreatment; Lignocellulosic biomass
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2015.01.079

Miscanthus sacchariflorus 'Goedae-Uksae 1' (GU) was developed as an energy crop of high productivity in Korea. For the practical use of GU for bioethanol production, a bench-scale continuous pretreatment system was developed. The reactor performed screw extrusion, soaking and thermochemical pretreatment at the following operating conditions: 3 mm particle size, 22% moisture content, 140 °C reaction temperature, 8 min residence time, 15 g/min biomass feeding and 120 mL/min NaOH input. As a result of minimizing NaOH concentration and enzyme dosage, 90.8±0.49% glucose yield was obtained from 0.5 M NaOH-pretreated GU containing 3% glucan with 10 FPU cellulase/g cellulose at 50 °C for 72 h. The separate hydrolysis and fermentation of 0.5 M NaOH-pretreated GU containing 10% glucan with 10-30 FPU for 102 h produced 43.0-49.6 g/L bioethanol (theoretical yield, 75.8-87.6%). Thus, this study demonstrated that continuous pretreatment using a single screw reactor is effective for bioethanol production from Miscanthus biomass.