Alkali Treatment and Cellulose Nanowhiskers Extracted from Maize Stalk Residues

Abstract

The aim of this study was to investigate the use of effect of pulveriser and extraction of cellulosenanowhiskers (CNWs) on Maize stalks. Maize stalk residues were first subjected to a cutting mill for size reduction purified using mechanical, chemical extraction and bleaching. After chemical extraction, high quality cellulose resulted and cellulose nanowhiskers (CNW) were then extracted using chemical acid hydrolysis. The chemical compositions and mechanical properties of the maize stalk residues were examined before and after purification by using standard methods, Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and thermo gravimetric analysis (TGA). The morphology and dimensions of the isolated cellulose nanowhiskers were characterized using atomic force microscope (AFM). The crystallinity index increased upon mechanical and chemical extraction. Thermal stability of cellulose derived from maize stalk improved with chemical treatment due to new functional groups introduced on the surface and enhancement in crystallinity. Highly dispersed cellulose nanowhiskers (CNWs) were successfully extracted from maize stalk residues with diameters ranging between 3 and 7 nm, length ranges between 150 -450 nm, respectively.

Thermoplastic Processing of PLA/Cellulose Nanomaterials Composites

“…CNMs can be extracted from different natural sources (wood, non-woody and animal materials), by mechanical treatment and acid hydrolysis or combination of the two. They can broadly be grouped into five categories, viz., cellulose nanofibers (CNF), cellulose nanocrystals (CNCs), bacterial cellulose (BC), algal cellulose (AC), and tunicate cellulose depending on the source and extraction method, as discussed below [3,7,18,19,20,21,22,23].…”

Characterization of Nanofibrillated Cellulose Produced by Different Methods from Cabbage Outer Leaves

“…Naturally, cellulose nanofibers are embedded in such matrix substances as hemicelluloses and lignin. Alkaline hydrolysis helped dissolve hemicelluloses (Motaung & Mtibe, ) and separate structural linkages between lignin and carbohydrates (Islam et al., ). Bleaching, which was applied after alkali hydrolysis, also helped eliminate phenolic groups in lignin, leading to the disruption of the lignin structure (Abraham et al., ; Motaung & Mtibe, ).…”

“…Alkaline hydrolysis helped dissolve hemicelluloses (Motaung & Mtibe, ) and separate structural linkages between lignin and carbohydrates (Islam et al., ). Bleaching, which was applied after alkali hydrolysis, also helped eliminate phenolic groups in lignin, leading to the disruption of the lignin structure (Abraham et al., ; Motaung & Mtibe, ). Previous works indeed reported similar decrease in the lignin content after alkaline treatment with NaOH and NaClO 2 (Rambabu, Panthapulakkal, Sain, & Dalai, ).…”

Variation in the Inter-Node Length During Plant Growth Influences the Tensile Strength of Maize Stem Fibres.

“…However, this can be a good source of cellulosic bres. Furthermore, the few experimental-based research studies [3][4][5][6][7][8][9] on maize bres done till date have all shown that maize bre has proved to be interesting by reason of its appreciable mechanical and chemical properties. From literature, it has been noted that extraction of maize bres has been done by using either chemicals accompanied by boiling or milling equipment [3-5, 7, 9].…”