Removal of congo red dye from aqueous solution using nano ZnO/chitosan composite

Nano ZnO/chitosan composite was synthesized using precipitation method. The material was characterized by physicochemical analysis methods including XRD and TEM. The results showed that the spherical and rod-shaped particles were well-dispersed with the average size of 30-40 nm. The ZnO/chitosan composite was applied as an adsorbent to remove congo red from aqueous solution. Equilibrium data fitted well with the Langmuir model. It is assumed that the adsorption process follows the pseudo-second-order kinetics equation. The maximum adsorption capacity was of 281.69 mg/g. This suggested that the material could be a promising adsorbent for colorants removal in aqueous solutions.