Equilibrium and Kinetic studies on adsorption of methyl orange from aqueous solution on chitosan/kaolin/γ-Fe2O3 nanocomposite

Adsorption of anionic azo dye methyl orange (MO) on chitosan/kaolin/γ-Fe₂O₃ nanocomposite from aqueous solutions was investigated in a batch system with respect to adsorbent dosage and initial pH. The pseudo-first-order, pseudo-second-order kinetic models and intra-particle diffusion model were used to evaluate the kinetic data and the rate diffusion model constants were calculated. Results of the kinetic studies showed that MO dye onto chitosan/kaolin/γ-Fe₂O₃ nanocomposite was better described by the pseudo-second-order kinetic model. The Langmuir isotherm provided the better correlation for MO adsorption onto chitosan/kaolin/γ-Fe₂O₃ nanocomposite. The maximum adsorption capacities were 36.67 and 35.27 mg g^-1 for MO adsorption at 310 and 320 K.