Processing and effective utilization of lignocellulosic biomass: Nanocellulose, nanolignin, and nanoxylan for wastewater treatment

Abstract Nanotechnology has proven to make the processing of lignocellulosic biomass much easier and efficient by reducing potential complications and harmful side effects. The overall cost of operations, transport, and disposal has also been reduced. Recovery, reusability, and purification of lignocellulosic biomass are found to be efficient when nanotechnological approaches are employed. Lignocellulosic biomass for enhancing the quality of water has attracted increasing interest among many researchers. Nanoforms of lignocellulosic biomass include nanocellulose, nanolignin, and nanoxylan. Heavy metal removal by nanocellulose has been reported to exhibit an efficiency of 99% against copper and iron metals. Membranes consisting of nanocellulose crystals extracted from shrimp shell wastes can eliminate Victoria blue dye by 98%. Escherichia coli has been treated successfully using nanocellulose composites conjugated with silver with 96.9% efficiency. Nano-lignin particles have reported 98% removal of methylene blue, while a composite of the same with palladium and iron oxide has exhibited 99% elimination of the toxic dye. Lignin-based nanomaterials are suggested to be reproducible and regenerated by heat and squeeze treatments, thus releasing the entire adsorbed contaminants to free the substrate for subsequent use. Further carbonation maximizes the absorption by 522 times more than its own weight, with a removal efficiency of 96%. Nanotization of lignocellulosic biomass gives enhanced mechanical, chemical, and biological properties that aid researchers to modify these woody polymers into membranes, flocculants, dye adsorbents, metal adsorbents, and oil separators in wastewater treatment. The present review deals with potential applications of nanoforms of lignocellulosic biomass for wastewater remediation.