Available online 8 February 2023

Deep eutectic solvents (DESs) have gained increasing attention as alternative solvents of environmental unfriendly solvents for biomass pretreatment.

In this study, bioethanol production from DESs-pretreated corn straw was investigated. The results revealed effective lignin removal from corn straw after pretreatment with choline chloride/oxalic acid (C:O), choline chloride/glycerol (C:G), or choline chloride/urea (C:U) DESs. After pretreatment with DESs, cellulose conversion significantly increased to 96.51% from 44.35% in the case of untreated corn straw. The best performance was obtained after the pretreatment of corn straw with C:O with a mass ratio of 1:15 at 120°C for 6 h, and this was mainly attributed to high lignin removal (60.60%). Another experiment showed that corn straw pretreated with C:G had a cellulose conversion of 86.82%, a glucose yield of 63.57%, and an ethanol yield of 54.86%.

Overall, this study demonstrated that the pretreatment of corn straw by a suitable DES can lead to efficient bioethanol production.

Alternative solvents

Bioethanol production

Cellulose conversion

Corn straw

Deep eutectic solvents

Enzymatic hydrolysis

Lignin removal

Pretreatment

© 2023 Published by Elsevier Ltd. on behalf of Pontificia Universidad Católica de Valparaíso.