Efficient preparation of cellulose nanocrystals with a high yield through simultaneous acidolysis with a heat–moisture treatment

This study developed a novel method for the facile and efficient preparation of the cellulose nanocrystals (CNCs) by using a simultaneous collaborative process combining sulfuric acid hydrolysis and heat–moisture treatment. In this work, we significantly reduced acid dosage compared to conventional acid solution hydrolysis methods to prepare CNCs. The weight of diluted sulfuric acid is no more than 25% on dry basis weight of microcrystalline cellulose. In a relatively short time (2 h), the yield could reach 93.68%, which is higher than the existing methods. The obtained CNCs displayed a normal rod-like shape (100 nm) and unusual spherical shape (10 nm) and showed high relative crystallinity ranged from 70.92% to 81.13%. The combination of acidolysis and heat-moisture treatment may be an economical and effective method for large–scale production of CNCs and provides a new method for preparing short CNCs, which can be used in membrane strengthening and food packages