Switchable Ionic Liquids as Delignification Solvents for Lignocellulosic Materials

A1 Journal article (refereed)

Internal Authors/Editors

Publication Details

List of Authors: Ikenna Anugwom, Valerie Eta, Pasi Virtanen, Päivi Mäki-Arvela, Mattias Hedenström, Michael Hummel, Herbert Sixta, Jyri-Pekka Mikkola
Publisher: Wiley
Publication year: 2014
Journal: ChemSusChem
Journal acronym: ChemSusChem
Volume number: 7
Issue number: 4
Start page: 1170
End page: 1176
eISSN: 1864-564X


The transformation of lignocellulosic materials into potentially valuable resources is compromised by their complicated structure. Consequently, new economical and feasible conversion/fractionation techniques that render value-added products are intensely investigated. Herein an unorthodox and feasible fractionation method of birch chips (B.pendula) using a switchable ionic liquid (SIL) derived from an alkanol amine (monoethanol amine, MEA) and an organic super base (1,8-diazabicyclo-[5.4.0]-undec-7-ene, DBU) with two different trigger acid gases (CO2 and SO2) is studied. After SIL treatment, the dissolved fractions were selectively separated by a step-wise method using an antisolvent to induce precipitation. The SIL was recycled after concentration and evaporation of anti-solvent. The composition of undissolved wood after MEA-SO2-SIL treatment resulted in 80wt% cellulose, 10wt% hemicelluloses, and 3wt% lignin, whereas MEA-CO2-SIL treatment resulted in 66wt% cellulose, 12wt% hemicelluloses and 11wt% lignin. Thus, the MEA-SO2-SIL proved more efficient than the MEA-CO2-SIL, and a better solvent for lignin removal. All fractions were analyzed by gas chromatography (GC), Fourier transform infrared spectroscopy (FT-IR), C-13 nuclear magnetic resonance spectroscopy (NMR) and Gel permeation chromatography (GPC).


Alkanol amines, Biomass, Delignification, Ionic liquids, Organic superbases

Last updated on 2020-30-05 at 03:31