Fractionation of cellulose and lignin from sugarcane bagasse via the alkaline and acid chemical process

¹ Department of Environmental Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Florida Campus, South Africa
² Faculty of Science and Agriculture, University of Fort Hare, Alice Campus, South Africa

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 5 February 2026

Abstract

This research aimed to fractionate cellulose and lignin from sugarcane bagasse (SCB) using the alkaline and acid chemical process. Sulphuric acid (H₂SO₄) and Sodium hydroxide (NaOH) were selected as the pretreatment chemical solvents. After pretreatment, the cellulose content and lignin were 98.5% and 79.2%, respectively. Fourier Transform Infrared (FTIR) Spectroscopy, ¹H and ¹³C Nuclear Magnetic Resonance (NMR), and Scanning Electron Microscopy (SEM) were employed to analyse the material. Raw SCB shows the vibration absorption peaks of O-H and C-H stretching at 338.23 and 2897.37 cm^-1, which are correlated with cellulose, hemicellulose, and lignin molecules. The vibration of O-H and C-H functional groups was observed on extracted cellulose and lignin biopolymers. However, the intensity of vibration peaks decreased, especially for lignin biopolymer. The absorption band observed at 1603.74 and 1541 cm^-1 was attributed to the aromatic (C=O, C=C) structure. ¹H and ¹³C NMR spectra detected the presence of both the aromatic regions and the sidechain regions on raw SCB and SCB-lignin. However, only the sidechain regions were detected on SCB-cellulose. SEM analysis reveals that the surfaces of raw SCB, SCB-cellulose, and SCB-lignin exhibit smooth, irregular, and uneven shapes, respectively. The results show that cellulose and lignin were simultaneously recovered from SCB.