Enhanced Cellulose Isolation from Sugarcane Bagasse through Sequential Alkali and Oxidative Treatment

Abstract As the world seeks sustainable alternatives to fossil-based materials, agricultural residues like sugarcane bagasse are gaining prominence as valuable bioresources. Sugarcane bagasse, the fibrous waste left after juice extraction, is an agricultural residue that is particularly rich in cellulose, a biopolymer with immense potential for green material innovation. The present work utilised sugarcane bagasse, to obtain cellulose by optimising the Sodium hydroxide (NaOH) and Sodium hypochlorite (NaOCl) concentrations. Characterisation techniques such as Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscope (FE-SEM) and X-ray Diffraction (XRD) were employed for detailed analysis. This article also encloses the effect of NaOH and NaOCl concentration on the cellulose yield and the various possible applications of the obtained cellulose. To evaluate statistical significance, one-way ANOVA was performed, complemented by Tukey’s multiple comparison test. Compositional analysis showed that the cellulose content of raw sugarcane bagasse was 42.6±1.5%. However, after alkali and bleaching treatment, the cellulose content was in the range 42.6±0.6% - 56.5±0.5%. FTIR analysis confirmed the successful cellulose extraction from sugarcane bagasse, as evidenced by the disappearance of lignin and hemicellulose associated peaks and characteristic cellulose absorption bands. XRD analysis revealed an increase in the crystallinity index from 29.8% in SCB to 53.7% in extracted cellulose. Morphological analysis employing FE-SEM highlighted significant surface differences in SCB and extracted cellulose. Statistical analysis unfolded that amendment with NaOH and NaOCl enhanced the cellulose yield significantly (p≤0.05) compared to raw sugarcane bagasse. The study highlights the immense potential of agricultural waste as a renewable and cost-effective source of cellulose. By leveraging these residues, industries can reduce dependence on conventional raw materials while promoting sustainable and environmentally responsible practices.