Third-Component-Regulated Choline Chloride-Monoethanolamine-Based Solvent Systems for Enhanced Valorization of Bamboo...

Efficient pretreatment is essential for improving the conversion of lignocellulose into fermentable sugars and bioethanol. In this study, choline chloride-monoethanolamine (ChCl-MEA)-based solvent systems containing H₂O₂, NaHCO₃, Na₂S, or ethylene glycol were prepared and applied for the pretreatment of Dendrocalamus brandisii. Among the tested systems, ChCl-MEA-Na₂S showed the best overall pretreatment performance, achieving 92.8 ± 2.3% delignification and 86.1 ± 1.7% cellulose retention. It also effectively disrupted lignin-carbohydrate associations, reduced lignin shielding and generated a more accessible cellulose-rich substrate for bioconversion. In the following separation enzymatic hydrolysis and fermentation, 92.2 ± 2.2% cellulose in substrate was converted to glucose, and 17.49 ± 0.7 g/L ethanol was obtained via the fermentation of enzymatic hydrolysate. Taking the bioconversion of substrate into consideration, the ChCl-MEA-H₂O₂ and ChCl-MEA-Na₂S were recovered for full component utilization. Especially, the carbon dots produced from the degradation compounds in ChCl-MEA-H₂O₂ DESs had favorable antioxidation and antibacterial performance due to the oxygen-containing group caused by oxidation of H₂O₂.