Sustainable Cellulose-Bentonite Composites for Wastewater Treatment

Clean water and uncontaminated soil are fundamental for sustaining life on Earth and are essential for assuring human health, and the use of sustainable adsorption materials has emerged as an effective strategy to reduce the volume of effluents released into the environment. Cellulose-bentonite composites have shown significant promise in water purification due to their high adsorption capacity, structural stability, and eco-friendly nature, making them an effective material for the removal of a wide range of pollutants from contaminated water. The most commonly employed methods of fabrication of cellulose-bentonite composites include solution casting, in situ polymerization, and electrospinning. Wastewater typically contains a variety of toxic contaminants, including synthetic dyes such as Congo red and methylene blue, heavy metals such as Cu, Pb, Hg, Ni, pesticides, and oils. Cellulose-bentonite composites offer an economical and efficient solution for the removal of these pollutants, owing to their synergistic properties-especially when compared to other adsorbents such as activated carbon, nanographene oxide, and metal-organic frameworks (MOFs). However, a systematic evaluation of their fabrication strategies, adsorption mechanisms, and application-related studies remains lacking. Also, there is an urgent need for a comprehensive review that consolidates recent findings on the removal of environmental contaminants and highlights both individual and combined adsorption efficiencies. Therefore, this work focuses on cellulose-bentonite composites as highly promising materials for developing sustainable, high-performance adsorbents tailored for advanced water treatment technologies.