ABSTRACT
Biomass-derived deep eutectic solvents (DESs) have been introduced as
promising pretreatment and fractionation solvents because of their mild
processing conditions, easy synthesis, and green solvent components from
biomass. In recent DES studies, solvent-based third constituents like
water, ethanol, and others improve the processibility of typical binary
DESs. However, the impacts of these components are not well understood.
Here, two solvent-based constitutions, including water and ethylene
glycol, were applied to 3,4-dihydroxybenzoic acid (DHBA)-based DES
system for improving the conversion efficiency of cellulose-rich
fraction and the properties of lignin fraction. Chemical composition,
enzymatic digestibility, degree of polymerization of cellulose and
physicochemical properties of lignin were used to evaluate the impact of
each third constituent on biomass processing. Ternary DHBA-ChCl DESs
exhibited better performances in delignification, fermentable sugar
production, and preservation of β–O–4 ether linkage in lignin compared
to binary ChCl-DHBA DES.