Pengekstrakan dan pencirian selulosa daripada bahan buangan pertanian - Pelepah kelapa sawit

Abstract

Cellulose from oil palm fronds (OPF) was extracted using a cost-effective method combining physical treatment (high pressure steaming) and repeated chemical treatments (alkali and bleaching). Alkali and bleaching treatments were performed using low concentrations of sodium hydroxide and sodium chlorite, respectively. High levels of cellulose were successfully extracted, with 4 grams of cellulose for every 10 grams of raw oil palm fronds. The morphology of the cellulose was investigated using variable pressure scanning electron microscope (VPSEM). Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analyser (TGA) were used for structural analysis. The extracted cellulose was found to have smaller diameter (8 – 10 μm) and smoother surface compared to the untreated fibres. The results from FTIR, XRD and TGA indicate that the hemicelluloses and lignin were extensively removed from the isolated cellulose. Alkali treatment helped in removal of hemicelluloses, while bleaching assisted in delignification. The extracted cellulose showed high crystalline index of 68.75% and degradation temperature of 350 C resulted from removal of lignin and hemicelluloses via alkali and bleaching treatments.