Green and eco-friendly scalable synthesis of chitosan-carbon nanocomposite for efficient dye removal

The integration of activated carbon with chitosan (CS) for dye removal offers a multitude of benefits, making this hybrid material a promising and efficient solution for water purification. Activated carbon (C) was synthesized from fruit wastes and then mixed with CS for the preparation of chitosan‑carbon nanocomposite (CSCNC) using ball milling technique. XRD and ATR-FTIR techniques affirmed the preparation of CSCNC. Additionally, the findings obtained from TEM and SEM analyses signifying the deposition of activated carbon onto the surface of CS. The majority of particle size and polydispersity index (PdI) for CSCNC were found to be 162.8 nm and 0.483, respectively as displayed from DLS technique. The current research work was examined the adsorption and desorption behaviors of Methylene Blue (MB) using CSCNC. Adsorption experiments reveal a time-dependent process characterized by an initial rapid phase and gradual approach to equilibrium, with the pseudo-second-order kinetics model providing the best fit. The adsorption capacity exhibited a rising pattern as pH increased, reaching its peak value of 912.4 mg/g. Both Langmuir and Freundlich isotherm models explained the equilibrium relationship between MB and the nanocomposite, offering insights into maximum adsorption capacity and surface characteristics. Desorption studies explored the nanocomposite's regenerative potential under varying conditions. The findings contributed to the sustainable design of water treatment technologies, emphasizing the nanocomposite's efficiency, scalability, and regenerative capabilities.