Impact of deep eutectic solvent pre-treatment on the extraction of cellulose nanofibers

• Published in: Cellulose (London) 2024-11, Vol.31 (16), p.9645-9660
• Main Authors: Baraka, Farida, Erdocia, Xabier, Velazco-Cabral, Ivan, Hernández-Ramos, Fabio, Dávila-Rodríguez, Izaskun, Maugin, Marine, Labidi, Jalel
• Format: Article
• Language: English
• Subjects: Bioorganic Chemistry; Cellulose fibers; Ceramics; Chemistry; Chemistry and Materials Science; Composites; Glass; Imidazole; Lignocellulose; Nanofibers; Natural Materials; Organic Chemistry; Original Research; Physical Chemistry; Polymer Sciences; Pretreatment; Response surface methodology; Solubility; Solubilization; Solvents; Sustainable Development; Thermal stability
• ISSN: 0969-0239; 1572-882X
• DOI: 10.1007/s10570-024-06185-0

Deep Eutectic Solvents (DESs) have emerged as promising eco-friendly pre-treatment agents for lignocellulosic biomass, offering considerable advantages for the nanofibrillation process. This study investigates the impact of DESs on cellulose fibers morphology, focusing on solubilization phenomena in the amorphous regions that may facilitate cellulose nanofiber production. The pre-treatment process combining a DES (triethylmethylammonium chloride and imidazole, TEMA:IMD) with microwave (MW) energy was optimized to enhance the solubility of cellulosic fibers. A response surface methodology (RSM) was employed to optimize the DES-MW-assisted pre-treatment. Results show that the reaction time and the temperature significantly influence the solubility of cellulosic fibers. The optimized conditions resulted in cellulose fibers with low content of hemicellulose and lignin, high crystallinity index, and improved thermal stability. The effectiveness of DES-MW pre-treatment in producing cellulose nanofibers (CNFs) from native and pre-treated fibers was investigated. Cellulose fibers pre-treated with a DES yielded CNFs with a narrower diameter distribution. Overall, optimized DES-MW pre-treatment offers a promising strategy for the efficient and sustainable extraction of CNFs.