Separation of Cellulose and Lignin from Eucalyptus Wood by Liquefaction in Deep Eutectic Solvents

Lignin and cellulose were separated from eucalyptus wood powder by partial liquefaction in deep eutectic solvents (DESs). Approximately 97.4% of the original lignin in the eucalyptus wood was separated and recovered with a choline chloride-PEG 200 mixture. Lignin purity that was as high as 99% could be achieved by this separation method. The DES that was comprised of choline chloride, PEG 200, and glycerin could be used to separate the cellulose. The purity and the crystallinity of the isolated cellulose were as high as 92% and 73%, respectively. Experimental data showed that the examined DES systems could effectively separate the constituents of eucalypt wood powder.