Removal of organic dyes from aqueous solution using GO/SrO/MgO materials

In the current study, GO was prepared by modified Hummer’s method followed by the addition of SrO/MgO binary oxide using a precipitation approach. This study aims to eliminate mainly malachite green (MG), Eriochrome black T (EBT), and Congo red (CR) dyes from aqueous media. The GO/SrO/MgO materials have been characterized by using Fourier transfer infrared spectroscopy (FT-IR), X- ray diffraction (XRD), Scanning electron microscope (SEM) and Energy dispersive X- ray spectroscopy (EDX) techniques. The effect of different experimental parameters such as adsorbent dosage, initial dye concentration, contact time, pH of the solution and agitation speed have been investigated. The adsorption mechanism has been well explained by Langmuir adsorption isotherm with a maximum adsorption capacity (q_max) of 45.87 mg/g for MG, 50.15 mg/g for EBT and 45.24 mg/g for CR. The kinetic adsorption data has been best fitted on a pseudo-second-order kinetic model. The thermodynamic study reveals that the adsorption process is spontaneous and endothermic. The adsorption of organic dyes on adsorbent follows Hydrogen bonding, electrostatic interaction, π-π interaction, and surface diffusion. The adsorbent can be recovered and reused for the elimination of dyes.