Extraction of cellulose nanocrystals from mengkuang leaves (Pandanus tectorius)

Cellulose was extracted from mengkuang leaves (pandanus tectorius) by carrying out alkali and bleaching treatments. Cellulose nanocrystals were isolated from extracted cellulose with concentrated sulphuric acid. The chemical composition of mengkuang leaves was determined at different stages of treatment. Structural analysis was carried out by Fourier transform infrared spectroscopy and X-ray diffraction. Field emission scanning electron microscopy and transmission electron microscopy were used to investigate the morphology of the isolated cellulose and cellulose nanocrystal, respectively. The thermal stability of mengkuang leaves at different stages of treatment was investigated by thermogravimetric analysis. The results indicated that the hemicellulose and lignin were removed extensively from the extracted cellulose. The isolated cellulose and cellulose nanocrystals were found to have diameters in the range 5-80 mu m and 5-25 nm, respectively. The thermal stability of the leaves was found to increase at various purification stages when compared to the raw material. (c) 2012 Elsevier Ltd. All rights reserved.