, Volume 19, Issue 1, pp 307–312 | Cite as

The undesirable acetylation of cellulose by the acetate ion of 1-ethyl-3-methylimidazolium acetate

  • Sergios Kimon Karatzos
  • Leslie Alan Edye
  • Robert Mark Wellard


The ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([C2mim]OAc) is considered to be an inert solvent of cellulose and lignocellulosic biomass. Acetylation (1.7% mol, or DS 0.017) of cellulose after dissolution in technical grade [C2mim]OAc (150 °C for 20 min), is demonstrated by compositional analysis, FTIR analysis and 13C NMR spectroscopy (in [C2mim]OAc with 13C enriched acetate). This acetylation, in the absence of added acylating agents, has not been reported before and may limit [C2mim]OAc utility in industrial scale biomass processing, even at this low extent. For example, cellulose acetylation may contribute to IL loss in processes where the IL is recovered and reused and inhibit enzyme saccharification of cellulose in lignocellulosic biofuel production processes based on saccharification and fermentation.

Graphical abstract


Acetylation Cellulose Ionic liquids NMR 



Funding was generously provided by the Greek State Scholarship Foundation (IKY), the Queensland Government, and Queensland University of Technology.


  1. Aggarwal VK, Emme I, Mereu A (2002) Unexpected side reactions of imidazolium-based ionic liquids in the base-catalysed Baylis-Hillman reaction. Chem Commun 15:1612–1613CrossRefGoogle Scholar
  2. Bochek ZM, Kalyuzhnaya LM (2002) Interaction of water with cellulose and cellulose acetates as influenced by the hydrogen bond system and hydrophilic-hydrophobic balance of the macromolecules. Macromol Chem Polym Mater 75(6):989–993Google Scholar
  3. Dadi AP, Varanasi S, Schall CA (2006) Enhancement of cellulose saccharification kinetics using an ionic liquid pretreatment step. Biotechnol Bioeng 95(5):904–910CrossRefGoogle Scholar
  4. Ebner G, Schiehser S, Potthast A, Rosenau T (2008) Side reaction of cellulose with common 1-alkyl-3-methylimidazolium-based ionic liquids. Tetrahedron Lett 49:7322–7324CrossRefGoogle Scholar
  5. Heinze T, Dorn S, Schöbitz M, Liebert T, Köhler S, Meister F (2008) Interactions of ionic liquids with polysaccharides-2: cellulose. Macromol Symp 262(1):8–22CrossRefGoogle Scholar
  6. Köhler S, Liebert T, Schöbitz M, Schaller J, Meister F, Günther W, Heinze T (2007) Interactions of ionic liquids with polysaccharides 1. Unexpected acetylation of cellulose with 1-ethyl-3-methylimidazolium acetate. Macromol Rapid Commun 28 (24):2311–2317Google Scholar
  7. Lee SH, Doherty TV, Linhardt RJ, Dordick JS (2009) Ionic liquid-mediated selective extraction of lignin from wood leading to enhanced enzymatic cellulose hydrolysis. Biotechnol Bioeng 102(5):1368–1376CrossRefGoogle Scholar
  8. Liebert T (2008) Innovative concepts for the shaping and modification of cellulose. Macromol Symp 262:28–38CrossRefGoogle Scholar
  9. Mäki-Arvela P, Anugworm I, Virtanen P, Sjöholm R, Mikkola JP (2010) Dissolution of lignocellulosic materials and its constituents using ionic liquids—a review. Ind Crops Prod 32(3):175–201CrossRefGoogle Scholar
  10. Široký J, Blackburn R, Bechtold T, Taylor J, White P (2010) Attenuated total reflectance Fourier-transform infrared spectroscopy analysis of crystallinity changes in lyocell following continuous treatment with sodium hydroxide. Cellulose 17(1):103–115CrossRefGoogle Scholar
  11. Sluiter A, Hames B, Ruiz R, Scarlata C, Sluiter J, Templeton D, Crocker D (2008) Determination of structural carbohydrates and lignin in biomass. Laboratory analytical procedures. National Renewable Energy Laboratory, GoldenGoogle Scholar
  12. Sun N, Mustafizur R, Qin Y, Maxim ML, Rodrìquez H, Rogers RD (2009) Complete dissolution and partial delignification of wood in the ionic liquid 1-ethyl-3-methylimidazolium acetate. Green Chem 11(5):646–655CrossRefGoogle Scholar
  13. Taylor JK (1987) Quality assurance of chemical measurements. Lewis Publishers Inc, ChelseaGoogle Scholar
  14. Varanasi S, Schall CA, Dadi AP, Anderson J, Rao K (2008) Biomass pretreatment. US Patent 2008/0227162 A1Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Sergios Kimon Karatzos
    • 1
    • 2
  • Leslie Alan Edye
    • 1
  • Robert Mark Wellard
    • 1
  1. 1.School of ChemistryQueensland University of TechnologyBrisbaneAustralia
  2. 2.Faculty of Forestry, Department of Wood ScienceUniversity of British ColumbiaVancouverCanada

Personalised recommendations