Isolation and characterization of cellulose nanofibers from the aquatic weed water hyacinth: Eichhornia crassipes

Abstract

The water hyacinth is one of the fast growing perennial aquatic weeds with a height of 1 m and doubles their population in 2 weeks and is rich in fiber content. The cellulose nanofibers from the water blocking aquatic weed - water hyacinth - were successfully prepared. The crude and pure cellulose microfibers were initially obtained from the weed plant using the chemical treatments such as bleaching and alkaline and sodium chlorite reactions. The micron-sized fibers obtained from the stems were cryocrushed with liquid nitrogen to release the bundles of nanofibers and followed the sonication for individualization of fibers. The treated fibers were screened through Fourier transform infrared spectroscopy (FTIR) to confirm the removal of impurities from the fibers. The surface morphology of the aqueous suspension before cryocrushing and after the sonication process was investigated using scanning electron micros-copy (SEM) and transmission electron microscopy (TEM) techniques. Thermal stability of the fiber was increased after chemical treatment; this was confirmed by thermogravimetric analysis (TGA). The synthesized nanofibers were in a diameter range of 20-100 nm from the SEM and 25 nm from the TEM analysis. The extracted cellulose nanofibers from the noxious weeds were used for processing of biodegradable nanocomposites in drug delivery, ligament substitute, filtration, and water purification and also used as flexible optical display in electronics.