Biodegradable Hydrogel Pellets for Efficient Dye Adsorption: A Sustainable Approach to Industrial Effluent Treatment

Hydrogels are a special network of polymer chains capable of absorbing and retaining large volumes of water that are composed of naturally occurring polymers, synthetic polymers, or a combination of both. They are currently regarded as an appealing tool across various fields, including biomedicine, industry, and research, owing to their remarkable structural versatility. We report the preparation of biodegradable and nontoxic hydrogel pellets with carrageenan-k (4%), sodium alginate (1%) (CS, hydrogel pellet), and carrageenan-k (2%), xanthan gum (2%) (CX, hydrogel pellet). The precursors and prepared hydrogel pellets were characterized by TGA, DSC, and FT-IR. The pollutant removal properties of the hydrogel pellet were studied with Azure A (AA) and Azure B (AB) dye solutions monitored with a UV-Visible spectrophotometer, which revealed that the CS and CX of hydrogels showed efficient dye adsorption and were stable throughout the adsorption period. The hydrogel CS demonstrated greater dye adsorption efficiency in AA and AB dye solutions compared to hydrogel CX. This research, therefore, focuses on the preparation of hydrogels as adsorbents for the removal of dye molecules from the solution and sets hydrogels as a candidate to be considered for industrial dye effluent treatment.