Isolation of Cellulose Nanocrystals from Typha domingensis Named Southern Cattail Using a Batch Reactor

Cellulose nanocrystals (CNC) were obtained from Typha domingensis (an invasive macrophyte) collected from lagoons and wetlands in Altamira, Mexico. Cellulose extraction was carried out by a treatment with aqueous NaOH in a batch reactor followed by NaClO-bleaching and subsequent hydrolysis with sulfuric acid. The fibers were characterized by Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The crystallinity of the cellulose fibers isolated from Typha domingensis increased from 29 % (not treated fibers) to 73 % and the beginning of thermal degradation increased from 246 °C to 312 °C before and after the bleaching. The CNCs isolated from this plant show average values of 20 nm in diameter and 190 nm in length. Micrographs of the Typha domingensis fibers and the cellulose isolated therefrom as well as bleached cellulose indicate the removal of hemicellulose, lignin, and waxes from the fibers, which corroborates the XRD and FTIR results.