Removal of Direct Red 23 Dye Using CeO2/NiO/NiAl2O4 Nanocomposite: Mechanism, Kinetic, Thermodynamic, and Equilibrium Studies

We designed a facial and novel CeO2/NiO/NiAl2O4 nanocomposite prepared by recalcination of the cerium impregnated product of the primary calcined production of NiAl-NO3 layered double hydroxide (LDH) through the structural memory effect. The materialization of as-prepared nanocomposite was confirmed by Fourier-transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetry (TG), dynamic light scattering (DLS) and transmission electron microscopy (TEM). Morphologic studies revealed that the size of the nanocomposite was below 100 nm. The resulting mixed metal oxide nanocomposite was employed as an efficient adsorbent for the removal of Direct Red 23 (DR23) as a model pollutant from textile wastewater. The dye removal study showed >98% efficiency for the removal of dye which revealed the superiority of material for decontamination of waste water, while the maximum adsorption capacity determined from isotherm data was 588.24 mg of dye per g of the adsorbent. In addition, the reusability was also performed up to three cycles with 89, 85 and 88% efficiency for DR23. Also, thermodynamics, isotherm and kinetic studies were investigated. Overall, we offer a facile method for synthesizing CeO2/NiO/NiAl2O4 nanocomposite, efficiently decontaminating DR23 from water with good recyclability.