Comparative Study of the Photocatalytic Degradation of Crystal Violet Using Ferromagnetic Magnesium Oxide Nanoparticles and MgO-Bentonite Nanocomposite

Abstract

In this work, the exploitation of the synthesized magnesium oxide nanoparticles and MgO-bentonite nanocomposite as an effective photocatalyst has been reported. They were utilized to study their applicability for the photocatalytic degradation of crystal violet in wastewater. Fourier-transform infrared (FTIR) spectra, X-ray powder diffraction (XRPD), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscope (TEM) were used for characterization. The photocatalytic efficiency of the synthesized photocatalysts for CV decomposition has been optimized in terms of several factors such as pH, contact time, the dose of the catalyst, and the dye concentration. The maximum degradation efficiency of CV was found to be 99.19% at the optimum state of pH value of 7, using 0.2 g of MgO NPs, while in the case of MgO-bentonite nanocomposite, the maximum degradation efficiency was decreased to 83.38%. The photocatalytic reaction mechanism was investigated using the scavenging reaction process, revealing that holes were majorly responsible for the degradation of CV. The kinetic data were suitable and best fitted by the pseudo-first-order kinetic model.