Cellulose nanofibers for sustainable water filtration applications

Water pollution has become a global concern due to the continuous discharge of industrial effluents, agricultural runoff, and pharmaceutical residues into aquatic bodies, causing serious risks to both environmental and human health. Traditional water treatment methods, including chemical precipitation, membrane filtration, and biological processes, have limitations, including high operational costs, incomplete removal of emerging contaminants, and the generation of secondary pollutants. Due to these limitations, the use of bio-based nanomaterials is gaining attention for combining high performance with ecological safety. Cellulose nanofibers (CNFs) have emerged as promising nanomaterials derived from lignocellulosic biomass and agro waste. CNFs have unique physicochemical properties, including high surface area, nanoscale dimensions, high mechanical strength, and reactive hydroxyl groups that facilitate surface modification. These characteristics make CNFs highly suitable for water filtration applications, where they can effectively remove a wide range of pollutants through processes such as adsorption, electrostatic interaction, and chemical complexation. Recent studies further prove that CNF-based composite filters, including those integrated with natural materials such as clay, can efficiently remove antibiotic contaminants from wastewater. But the practical application The use of CNFs in large-scale water treatment remains restricted due to limited scalability, variability in raw material sources, and challenges with long-term stability and regeneration. The objective of this mini-review is to examine recent developments in the preparation, characterization, and application of CNFs for sustainable water filtration, with a focus on their mechanisms of pollutant removal.