Efficient binary diol-based deep eutectic solvent pretreatment for enhancing enzymatic saccharification and lignin fractionation from eucalyptus

• Published in: Bioresource technology 2024-11, Vol.412, p.131423, Article 131423
• Main Authors: He, Yulu, Shen, Ruojin, Shao, Lupeng, Wang, Chao, Yang, Guihua, Xu, Feng
• Format: Article
• Language: English
• Subjects: Biomass; Cellulase - chemistry; Cellulase - metabolism; cellulose; Chemical Fractionation - methods; choline; Deep eutectic solvent; Deep Eutectic Solvents - chemistry; delignification; Eucalyptus; Eucalyptus - chemistry; fractionation; glucose; Glucose - chemistry; Hydrolysis; lignin; Lignin - chemistry; Lignin nanoparticles; nanoparticles; Nanoparticles - chemistry; Pretreatment; Saccharification; solvents; Solvents - chemistry; xylan
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2024.131423

[Display omitted] •Novel EaCl-EG DES pretreatment of eucalyptus was developed.•The DES pretreatment removed lignin (85.0%) and preserved cellulose (94.5%).•Enzymatic digestibility after the EaCl-EG DES pretreatment exceeded 92.5%.•The recovered lignins were utilized to assemble lignin nanobottles. An innovative binary biol-based deep eutectic solvent (DES), specifically ethylamine hydrochloride-ethylene glycol (EaCl-EG), was developed for efficient pretreatment of eucalyptus biomass. This DES exhibited superior performance in achieving high delignification (85.0%) and xylan removal (80.0%), while preserving a significant amount of cellulose (94.5%) compared to choline chloride-based DES. Notably, the pretreated eucalyptus residues showed a remarkable glucose yield of over 92.5%, representing a substantial enhancement of up to 15 times compared to untreated eucalyptus. Furthermore, the pretreated liquor yielded high-purity lignin with a yield of 97.8%, characterized by well-preserved β-O-4 structure and nanoscale dimensions. These lignin nanoparticles (LNPs) were subsequently self-assembled into lignin nanobottles (LNBs), adding further value to the pretreatment process. The proposed novel binary EaCl-EG DES presented great potential as an efficient pretreatment solvent for future biomass fractionation processes.