Ionic liquid-mediated technology to produce cellulose nanocrystals directly from wood

Hatem Abushammala; Ingo Krossing; Marie-Pierre Laborie

doi:10.1016/j.carbpol.2015.07.079

Ionic liquid-mediated technology to produce cellulose nanocrystals directly from wood

Carbohydr Polym. 2015 Dec 10:134:609-16. doi: 10.1016/j.carbpol.2015.07.079. Epub 2015 Jul 26.

Authors

Hatem Abushammala¹, Ingo Krossing², Marie-Pierre Laborie³

Affiliations

¹ Chair of Forest Biomaterials, University of Freiburg, Werthmannstr. 6, 79085 Freiburg, Germany; Freiburg Materials Research Center, University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany. Electronic address: hatem.abushammala@biomat.uni-freiburg.de.
² Freiburg Materials Research Center, University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany; Institute of Inorganic and Analytical Chemistry, University of Freiburg, Albertstr. 21, 79104 Freiburg, Germany. Electronic address: krossing@uni-freiburg.de.
³ Chair of Forest Biomaterials, University of Freiburg, Werthmannstr. 6, 79085 Freiburg, Germany; Freiburg Materials Research Center, University of Freiburg, Stefan-Meier-Str. 21, 79104 Freiburg, Germany. Electronic address: marie-pierre.laborie@biomat.uni-freiburg.de.

PMID: 26428164
DOI: 10.1016/j.carbpol.2015.07.079

Abstract

We report for the first time the direct extraction of cellulose nanocrystals (CNCs) from wood by means of a 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]) treatment. A native cellulosic product could be recovered in 44% yield with respect to wood cellulose content. The product was analyzed for morphological (TEM, AFM, XRD), chemical (FTIR, (13)C CP/MAS NMR), thermal (DSC, TGA) and surface properties (Zeta potential, contact angle). These analyses evidenced the presence of partially acetylated (surface DS=0.28) nanocrystals of native cellulose I microstructure, with a crystallinity index of about 75% and aspect ratio of 65. Direct production of CNCs from wood is ascribed to the simultaneous capability of [EMIM][OAc] to (1) dissolve lignin in situ while only swelling cellulose, (2) decrease intermolecular cohesion in wood via acetylation, and (3) to catalyze cellulose hydrolysis.

Keywords: Cellulose nanocrystals; Hydrolysis; Ionic liquids; Wood pulping.

Publication types

Research Support, Non-U.S. Gov't