Efficacy of Novel NaX/MgO–TiO2 Zeolite Nanocomposite for the Adsorption of Methyl Orange (MO) Dye: Isotherm, Kinetic and Thermodynamic Studies

Abstract

The current study focuses on using the NaX/MgO–TiO2 zeolite nanocomposite for the adsorption of methyl orange (MO) organic dye from aqueous solution. For this purpose, MgO–TiO2 nanoparticles were firstly supported on the NaX zeolite using the ultrasound-assisted dispersion method at 450 °C. The obtained nanocomposite was well characterized by Field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray dot-mapping, Transmission electron microscopy (TEM), Atomic force microscopy (AFM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR). The UV–Vis results proved that MO was adsorbed on the nanocomposite after 35 min at 45 °C with a yield more than 95%. The different factors such as pH, adsorbent dose, contact time, adsorbent type, and initial concentration was applied to investigate the adsorption efficiency of NaX/MgO–TiO2 nanocomposite for the adsorption of MO dye. Also, Langmuir, Freundlich, and Temkin isotherm models were examined. The experimental adsorption isotherm was successfully verified by the Langmuir model with a maximum adsorption capacity 53.76 mg g−1 of MO on the NaX/MgO–TiO2 nanocomposite. The reaction kinetic was evaluated by employing the pseudo-first and second-orders models. The adsorption kinetic fit pseudo-second-order model. In addition, the investigation of the thermodynamic parameters including $$\Delta G^{O}$$,$$\Delta H^{O}$$, and $$\Delta S^{O}$$ indicated that adsorption reaction of MO was spontaneous, revealing physicochemical adsorption properties and endothermic process.