Comparative Analysis of Cellulose Characteristics from Three Agricultural Waste Biomasses

Recently, cellulose from agro-industrial wastes has attracted significant attention due to its high demand across various industries. In Ethiopia, corn husk (CH), corn cob (CC), and lupine husk (LH) are abundant lignocellulosic agricultural waste biomasses that can serve as potential alternative sources of cellulose. Thus, the objective of this study was to extract and characterize native cellulose from CH, CC, and LH. Cellulose fibers were isolated from these sources using alkaline and peroxyformic acid treatments. The isolated celluloses were then characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The cellulose yields obtained were 42% (CH-C), 33% (CC-C), and 36% (LH-C). The degree of polymerization of celluloses was 735.73 for CH-C, 667.29 for CC-C and 576.75 for LH-C. The FTIR spectra of cellulose indicated the removal of non-cellulosic constituents. The crystallinity index (CrI) values of the extracted celluloses were comparable to one another: LH-C (75.39%), CH-C (74.5%), and CC-C (72.86%). The SEM pictures of CH-C, CC-C, and LH-C showed micro-fibrillated structure. All samples of cellulose showed good thermal stability within the temperature range 20–700°C. Therefore, CH, CC, and LH are considered potential alternative source of cellulose for various industrial applications.