Applied Biochemistry and Biotechnology

, Volume 161, Issue 1, pp 22–33

Optimizing Dilute-Acid Pretreatment of Rapeseed Straw for Extraction of Hemicellulose

Authors

  • Tae-Su Jeong
    • Department of Applied Chemical EngineeringDankook University
  • Byung-Hwan Um
    • Forest Bioproducts Research Initiative, Department of Chemical and Biological EngineeringUniversity of Maine
  • Jun-Seok Kim
    • Department of Applied Chemical EngineeringKyonggi University
    • Department of Applied Chemical EngineeringDankook University
Article

DOI: 10.1007/s12010-009-8898-z

Cite this article as:
Jeong, T., Um, B., Kim, J. et al. Appl Biochem Biotechnol (2010) 161: 22. doi:10.1007/s12010-009-8898-z

Abstract

Biological conversion of biomass into fuels and chemicals requires hydrolysis of the polysaccharide fraction into monomeric sugars prior to fermentation. Hydrolysis can be performed enzymatically or with mineral acids. In this study, dilute sulfuric acid was used as a catalyst for the pretreatment of rapeseed straw. The purpose of this study is to optimize the pretreatment process in a 15-mL bomb tube reactor and investigate the effects of the acid concentration, temperature, and reaction time. These parameters influence hemicellulose removal and production of sugars (xylose, glucose, and arabinose) in the hydrolyzate as well as the formation of by-products (furfural, 5-hydroxymethylfurfural, and acetic acid). Statistical analysis was based on a model composition corresponding to a 33 orthogonal factorial design and employed the response surface methodology to optimize the pretreatment conditions, aiming to attain maximum xylan, mannan, and galactan (XMG) extraction from hemicellulose of rapeseed straw. The obtained optimum conditions were: H2SO4 concentration of 1.76% and temperature of 152.6 °C with a reaction time of 21 min. Under these optimal conditions, 85.5% of the total sugar was recovered after acid hydrolysis (78.9% XMG and 6.6% glucan). The hydrolyzate contained 1.60 g/L glucose, 0.61 g/L arabinose, 10.49 g/L xylose, mannose, and galactose, 0.39 g/L cellobiose, 0.94 g/L fructose, 0.02 g/L 1,6-anhydro-glucose, 1.17 g/L formic acid, 2.94 g/L acetic acid, 0.04 g/L levulinic acid, 0.04 g/L 5-hydroxymethylfurfural, and 0.98 g/L furfural.

Keywords

Rapeseed strawResponse surface methodology (RSM)Sulfuric acidPretreatment

Copyright information

© Springer Science+Business Media, LLC 2010