A neoteric approach for the complete valorization of Typha angustifolia leaf biomass: A drive towards environmental sustainability.

Abstract

Exploring new biomass resources and developing a sustainable process for holistic utilization has become crucial due to the high demand for bio-based chemicals as alternatives to petrochemicals. Herein, we describe a novel approach to valorize the Typha angustifolia leaves, underutilized biomass into cellulose, hemicellulose and lignin nanoparticles. The process was framed in a sequence to isolate hemicellulose in the first step due to its highly reactive nature and then separate cellulose and lignin. Among the various natural deep eutectic solvents used in screening experiments, LA/ChCl (2:1) was chosen for hemicellulose solubilization and a dissolution yield of 95.97±1.8% was obtained in 30min at 240W microwave power. Then the residual solid was delignified using NaOCl2 at 180W microwave power and a yield of 97±0.75% was obtained in 15min. Dissolved hemicellulose and lignin were precipitated using anti-solvents. The proposed approach achieved a recovery yield of 95.5±1.2% cellulose, 91.9±2.6% hemicellulose and 89.5±1.6% lignin. Subsequently, the isolated particles were converted into nanoparticles by intense ultrasonication. Spherical shaped nanocellulose, nanohemicellulose and nanolignin were obtained with an average size of 76±7nm, 86±9nm, and 64±5nm, respectively. The produced nanocellulose had a crystallinity of 77.36% with the thermal stability of 265°C. Nanohemicellulose and nanolignin were found to be semicrystalline with thermal stability up to 245°C and 275°C, respectively. The characterization results of the nanoparticles isolated from Typha angustifolia leaves are indicative of their wide range of biomedical and material science applications. This research could open a window for complete utilization of biomass in biorefinery and sustainable management of an invasive plant Typha angustifolia.