FUNCTIONAL CELLULOSE-BASED GELS USED IN WASTEWATER REMEDIATION, WITH A FOCUS ON HEAVY METALS AND DYE REMOVAL: A CRITICAL REVIEW

Water pollution remains a critical global challenge, exacerbated by increasing pressure on freshwater resources and the lack of access to clean drinking water for millions of people. This review investigates the potential of nanocellulose-based materials in water purification, with a specific focus on their application as an adsorbent, photocatalyst, and catalyst/support for adsorbents. To overcome the limitations of conventional treatment methods, various strategies for fabricating cellulose-based aerogels are examined. The review outlines the processes involved in biomass-derived cellulose extraction, nanocellulose preparation, and the development of hybrid aerogels. A major source of water contamination is the presence of heavy metals and synthetic dye pollutants. This comprehensive review highlights the use of cellulose-based gel materials for the effective removal of heavy metals and dyes from wastewater. In addition, it explores the underlying mechanisms involved in mitigating the toxicity of these pollutants using cellulose-based aerogels, ion-exchange systems, flocculants, and other biosorbents incorporating nanocellulose.