Eco‐Friendly PVA / CS / CNF Hydrogels as Adsorbents for Aqueous Dye Removal

ABSTRACT This study successfully prepared and evaluated polyvinyl alcohol (PVA)/chitosan (CS)/cellulose nanofiber (CNF) composite hydrogels for aqueous dye removal, with methylene blue (MB) used as a model pollutant. The hydrogels were fabricated using a freeze–thaw cycling method to form a three‐dimensional cross‐linked network. Their microstructure, mechanical properties, adhesion behavior, and MB adsorption performance were systematically investigated. The results showed that the hydrogel exhibited a high adsorption capacity for MB, with a maximum equilibrium adsorption of 79.5 mg/g. The adsorption process followed the pseudo‐second‐order kinetic model, suggesting that chemisorption was the dominant mechanism. In addition, the hydrogel demonstrated excellent mechanical properties, environmental stability, and biodegradability, indicating its potential as a sustainable material for eco‐friendly dye adsorption applications. This study provides new insights into the development of efficient and environmentally friendly adsorbents for dye removal from aqueous systems.