Pretreatment approaches are highly desirable to improve the commercial viability of nanocellulose production. In this study, we propose a new approach to mass produce nanocellulose using a hydrated choline chloride/oxalic acid dihydrate deep eutectic solvent (DES) combined with an ultrasonic process. The hydrogen bond acidity, polarizability, and solvation effect reflected by the Kamlet–Taft solvatochromic parameters did not decrease even after the addition of large amounts of water. Instead, the water facilitated the ionization of H+ and delocalization of Cl– ions, forming new Cl–H2O ionic hydrogen and oxalate–H2O hydrogen bonds, which are critical for improving the solvent characteristics. One pass of kraft pulp through the hydrated DESs (80 °C, 1 h) was sufficient to dissociate the kraft pulp into cellulose nanofibers or cellulose nanocrystals using an 800 W ultrasonic treatment. The present study represents an alternative route for the kraft pulp pretreatment and the large-scale production of nanocellulose.
Wei Liu,Kun Liu,Yaxuan Wang,Qingyi Lin,Jialin Liu,Haishun Du,Bo Pang,Chuanling Si
Cellulose nanofibers (CNFs) have been shown to assemble at oil/water interface and act as Pickering emulsions stabilizers. Developing a simple approach to fabricate CNFs with tunable surface properties and elucidating the influence of the surface properties of the CNFs on their emulsifying performance are of great significance and highly demanded. Herein, a facile approach, namely FeCl 3 -catalyzed formic acid hydrolysis in combination with high pressure homogenization was reported to produce CNFs using industrial Kraft pulp as raw materials. The surface properties, especially the surface wettability of the CNFs could be easily adjusted by changing the hydrolysis time. Additionally, the emulsifying performance of the CNFs and the stability of CNF-stabilized Pickering emulsions were also evaluated. The obtained CNF-stabilized Pickering emulsions demonstrated great stability under various ionic strengths ranging from 0 to 1 M NaCl and high temperature of 80 °C. This work would greatly improve the possibility of sustainable production of CNFs for practical emulsions.
危险品化学品经营许可证（带存储）