Hydrodynamic cavitation as a promising pretreatment technology to enhance the efficiency of cellulose nanocrystal production via enzymatic hydrolysis

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2023-09, Vol.472, p.144821, Article 144821
• Main Authors: Yupanqui-Mendoza, Sergio Luis, Prado, Carina Aline, Santos, Júlio Cesar dos, Arantes, Valdeir
• Format: Article
• Language: English
• Subjects: Cellulase; Cellulose nanocrystals; Enzymatic hydrolysis; Nanocellulose; Pretreatment
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2023.144821

[Display omitted] •Hydrodynamic cavitation induces structural deconstructions in cellulose fibers.•The application of cavitation reduces total process energy consumption by 41%.•Yield in the production of cellulose nanocrystals increased by up to 60%.•High-purity cellulose nanocrystals with tunable properties were successfully produced. Enzymatic hydrolysis to produce cellulose nanocrystals (CNCs) offers economical and sustainability advantages. However, since this is still an emerging technology, further improvements are needed to make the process feasible for scale-up. In our study, we propose a novel approach using hydrodynamic cavitation (HC) as a pretreatment technology to enhance the efficiency and yield of CNC production. HC treatments conducted under various scenarios induced structural modifications of the cellulose fibers that facilitated their defibrillation and subsequent enzymatic hydrolysis. Isolation through hydrolysis involved the synergistic action of specific enzymes, including xylanase and endoglucanase. Xylanase acted on the hemicellulosic fraction, breaking down the xylan structure and exposing the cellulose fibers. Subsequently, endoglucanase targeted the amorphous regions of cellulose, releasing CNCs. By integrating the HC pretreatment with enzymatic hydrolysis, we achieved remarkable results. High-yield CNCs, reaching approximately 60%, were obtained with a crystallinity index ranging from 81% to 85%. Moreover, this process demonstrated a significant reduction in total energy consumption of approximately 56%, contributing to its economic viability. Furthermore, CNCs with diverse morphologies, aspect ratios, and viscosity profiles were produced, enabling the tailoring of their properties for specific and new applications.