Synthesis and Morphological Studies of Nanocellulose Fibers from Lignocellulosic Biomass in Ionic Liquid

Abstract

Lignocellulosic agricultural biomasses and wood are the two most important natural sources of cellulose available on the planet. When chemically treated, cellulose is the world’s most common and widely used biopolymer, with properties such as low price, good toughness, good biocompatibility and good thermal stability. In this study, nanocellulose was extracted from ragi stalk, mango wood and groundnut husk. The cellulose was alkali-treated with NaOH and bleached with sodium chlorite to remove lignin and hemicellulose. Ionic liquid (1-butyl-3-methylimidazolium chloride ([Bmim]Cl) solvent was used to treat the obtained cellulose. FTIR spectra highlight the functional groups and substantial conversion of cellulose to nanocellulose. The crystalline or semi-crystalline nature of synthesized nanocellulose was illustrated by XRD. The TEM images record the size of synthesized nanocellulose between 11.12 and 31.16 nm. The reduction in size is mainly due to ultrasonication and centrifugation. The thermal stability of the obtained nanocellulose was evidenced using TGA/DTA. The thermal studies insight that the synthesized nanocellulose samples possess superior degradation temperature up to 473.8 ºC.