Pretreatment of yellow pine in an acidic ionic liquid: Extraction of hemicellulose and lignin to facilitate enzymatic digestion

• Published in: Bioresource technology Vol. 134; pp. 59 - 65
• Main Authors: Cox, Blair J., Ekerdt, John G.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-04-2013; Elsevier
• Subjects: Biological and medical sciences; Biotechnology; Biotechnology - methods; Borates - pharmacology; Cellulase - metabolism; Cellulose; Degradation; Dissolution; Fundamental and applied biological sciences. Psychology; Glucose - analysis; Imidazoles - pharmacology; Ionic liquid; Ionic liquids; Ionic Liquids - pharmacology; Lignin; Lignin - isolation & purification; Lignocellulose; Mannose - analysis; Pine; Pinus - drug effects; Polysaccharides - isolation & purification; Pretreatment; Saccharification; Sulfuric Acids - pharmacology; Trichoderma - enzymology; Walls; Lignin; Pretreatment; Lignocellulose; Ionic liquid; Facilitation; Hemicellulose; Enzymatic digestion; Acidity; Lignocellulosics
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2013.01.081

► Pine wood was treated with 1-H-methylimidazolium chloride. ► Treatment effectively removed lignin and hemicellulose. ► Cellulose rich fractions were hydrolyzed into glucose with cellulase. ► Demonstration of reactive delignification in ionic liquids for pretreatment.
The acidic ionic liquid 1-H-3-methylimidazolium chloride can effectively pretreat yellow pine wood chips under mild conditions for enzymatic saccharification. Wood samples were treated at temperatures between 110 and 150°C for up to 5h in the ionic liquid and three fractions collected; a cellulose rich fraction, lignin, and an aqueous fraction. This treatment caused the hemicellulose and the lignin to be degraded and dissolved from the cell walls of the pine wood. The lignin was depolymerized and subsequently dissolved in the ionic liquid. This process occurred more quickly at higher temperatures, although at the highest temperatures tested, significant cellulose degradation also occurred. The cellulose rich fraction was saccharified using cellulase from Trichoderma viride, with longer pretreatment times at 130°C resulting in higher glucose yields.