Adsorption of the eosin yellow dye by nickel oxide nanoparticles catalyzes via oxalate co-precipitation method: isotherm, kinetic and thermodynamic studies

Abstract

The Batch technique was used in the adsorption of eosin yellow (EY) dye from an aqueous solution by Nickel Oxide (NiO) nanoparticles (NPs). The Nickel Oxide nano-powder was synthesized by co-precipitation oxalate method and studied by x-ray diffraction (XRD), Scanning electron microscope (SEM) and Fourier transforms infrared spectroscopy (FTIR). The adsorbent Dosage, pH, contact time, and concentration of an aqueous solution were studied. Maximum eosin yellow dye removal efficiency was found to be 98.6% at pH 4, temperature 20 °C, initial dye concentration 10 mg l−1 (ppm), and the adsorbent dosage 0.05g at time 25 min. The adsorption process followed the Langmuir isotherm model with a maximum sorption capacity of 5.2167 and fitted to the pseudo-second-order kinetic model with a high correlation coefficient of 0.9941. Thermodynamic factors were determined and the obtained values refer that the adsorption of EY on NiO NPs is endothermic, non-spontaneous, and chemisorption processes.