Characterization, Compositional and Thermogravimetric Analyses of Lignocellulosic Fibers of Syzygium Cumini (L.) Leaf Litter: Investigating the Potential for Biofuel Production

The quest for greener and more sustainable energy sources has led to the consideration of lignocellulosic materials as possible candidates for this purpose. The present study investigated the potential of Syzygium cumini leaf litter as a lignocellulose source for biofuel production. The study involved comprehensive characterization (compositional, proximate, thermogravimetric, and Fourier Transform Infrared analyses) of raw Syzygium cumini (RSC) fibers and lignocellulose extracted from the plant, termed lignocellulose Syzygium cumini (LSC). RSC fibers were composed of lignocellulosic, cellulose, hemicellulose, and lignin contents of 60%, 50.52%, 31.53%, and 17.95%, respectively, indicating their potential for biofuel production. Nitrogen and fatty acid contents were significantly depleted after alkaline hydrolysis of RSC fibers from 0.532% to 0.196% and 2.5% to 1.0%, respectively. Thermogravimetric and differential thermal analyses at 10 °C/min recorded a steady mass for LSC between 0 to 20 mins until it reached 250 °C indicating thermal stability. However, a 28% mass reduction was reported for RSC between the temperature range of 50 °C – 200 °C, suggesting the presence of volatile compounds, including amino acids, and oxides of nitrogen and sulfur. The FTIR spectra of RSC and LSC fibers confirmed the presence of several organic functional groups. The peaks at 1023.2 for RSC and 1026.9 for LSC indicate the presence of an alkyl amine group, cyclic alkene or OH group while the peak at 1606.5 indicates unsaturated C=C bond. The compositional variations in LSC fibers distinctively showed the presence of C=O and C–O which were not depicted in the RSC spectra. Overall, the high lignocellulose content, low nitrogen values and high decomposition of 79.25% at 466.71 °C, renders LSC fiber a viable raw material for biofuel production.