Extraction of cellulose from rice husk, corn stem, corn tassel and oil palm empty fruit bunch using alkaline pretreatment and bleaching process

This study aims to extract cellulose from various agricultural residues, including rice husk (RH), corn stem (CS), corn tassel (CT), and oil palm empty fruit bunch (OPEFB), using an alkaline extraction method to address the issue of non-biodegradable microbead production. Delignification was done by employing sodium hydroxide for rice husk and a toluene-ethanol mixture for corn stem, corn tassel, and oil palm empty fruit bunch. Bleaching agents included sodium hypochlorite (NaOCl) for rice husk and a mixture of sodium hydroxide and acetic acid for CS, CT, and OPEFB. The functional groups, structural morphology, crystallinity, and thermal stability of the extracted cellulose were characterized using Fourier Transformed Infra-Red Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Thermogravimetric Analysis (TGA), respectively. The results reveal that OPEFB yielded the highest cellulose percentage at 31.40%, followed by RH (29.28%), CS (14.30%), and CT (13.27%). Characterization of the samples demonstrated that the alkaline treatment effectively enhanced the cellulose content by eliminating hemicellulose, lignin, and other impurities. Among the samples, RH subjected to alkaline extraction exhibited the highest crystallinity percentage at 59.42%, with CS (54.17%), CT (44.97%), and OPEFB (42.78%)