Removal of Eosin Yellow dye by Magnesium Oxide nanoparticles: isotherm, kinetic and thermodynamic studies

Abstract

Magnesium Oxide (MgO NPs) was synthesized by the oxalate co-precipitation method. The synthesized MgO NPs were characterized by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Fourier Transform Infrared Spectroscopy (FTIR). Then used for adsorption of Eosin Yellow (EY) dye. Many factors such as dosage of adsorbent, concentration, contact time, PH, and temperature were studied and maximum removal efficiency of EY was found to be 97.81074% at PH 4, temperature 50 C^o, contact time 60 min, concentration 30 mg/L and mass of adsorbent 0.03g/L. Langmuir isotherm model was fitted to the experimental data with maximum sorption capacity 11.53004 mg/g and followed the pseudo-second-order kinetic model with correlation coefficient 0.99795. The adsorption process was spontaneous with Gibbs free energy ?G (-2.80238 Kj/mol) and activation energy E_a (10.0522761 Kj/mol) which indicates a chemisorption process. Magnesium Oxide nanoparticles have approved their ability for adsorption of anionic dyes.