Use of Low‐Energy Ultrasonication to Enhance the Purity and Morphology of Cellulose Nanofibers Prepared from Areca Nut Shells.

The isolation of cellulose nanofibers from areca nut shell has been successfully carried out using a simple alkaline treatment, acid hydrolysis, and followed by a morphological modification using low‐energy sonication method. The alkaline treatment consists of dewaxing and bleaching process to remove lignin, while acid hydrolysis process was carried out to remove hemicellulose. Mechanical fibrillation was carried out via ultrasonication and low‐power homogenization with 100 W cleaner and 3 W homogenizer to obtain fine fibers. Following the scanning electron microscope (SEM) result, the ultrasonicated treatment sample showed better lignin and hemicellulose removal processes and increased dispersity, as well as reduce diameter of cellulose fibers from 710.4 to 451.6 nm. The particle size analyzer (PSA) showed that the colloidal cellulose after sonication provide a frequent diameter of 56 nm. Fourier transform infrared (FTIR) spectroscopy result showed that sonication is an effective removal process of noncellulosic components. X‐ray diffraction (XRD) analysis showed that the crystallinity of nanocellulose decrease following the sonication process. Hence, low‐energy ultrasonication is a viable approach to enhance the morphology and mechanical strength of cellulose nanofiber. [ABSTRACT FROM AUTHOR]