Thermodynamic and Kinetic Study of the Eosin Dye Removal from Aqueous Solution by ZnO Nanoparticles

Abstract

This research refers to the use of nanoparticles Zinc oxide (ZnO) in the removal of Eosin dye from aqueous solution by batch method. ZnO nanoparticles was characterized by using X-ray diffraction (XRD), Scanning electron microscopy (SEM), Atomic force microscope (AFM), Fourier transform infrared (FTIR) and the Brunauer–Emmett–Teller (BET) method. Optimum conditions for adsorption such as contact time, adsorbent dose, dye concentration, PH, and effect of temperature were studied. Contact time for the adsorption process was 2h. Adsorption isotherms been used to test the adsorption data (for Langmuir, Freundlich, Dubinin, Temkin) as it was fit to Freundlich isotherm. Thermodynamic functions data such as (ΔH°, ΔG°, ΔS°) of the adsorption process were calculated, which show the adsorption exothermic process and this process followed physisorption mechanism. Kinetic data were fit to pseudo- second order model.