Removal of Safranin Dye Using Graphene Oxide, Activated Carbon Nanocomposites, Aluminum Hydroxide and Oxide Graphene Nanoparticles, Activated Carbon and Cerium Oxide Nanoparticles

In this research, the following three adsorbents were synthesized and characterized to investigate the role of nanoparticles in the removal of the cationic dye safranin: a nanocomposite of graphene oxide-activated carbon (GO-AC) as a blank sample, graphene oxide-activated carbon-aluminum hydroxide nanoparticle (GO-AC-Al(OH)3 NPS) and graphene oxide-activated carbon-cerium oxide nanoparticles (GO-AC-CeO2 NPS). The synthesized nanomaterials were identified and characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS), and energy-dispersive X-ray spectroscopy (EDX). The effect of various parameters such as pH, initial dye concentration, adsorbent amount, contact time, and temperature in the safranin dye adsorption process was investigated. The used nanoparticles have a high surface area, good mechanical strength, and different functional groups. Graphene oxide, activated carbon, nanoparticles of cerium oxide, and aluminum hydroxide can be effective in the adsorption of safranin dye by forming various electrostatic interactions, π-π, and hydrogen bonds due to their different cavities and functional groups. Mechanisms affecting the removal of contaminants were studied with the Freundlich and Langmuir isotherm models. The results showed that the removal of safranin dye followed the Freundlich isotherm, and the value of the R2 correlation coefficient for oxide graphene /activated carbon, oxide graphene/activated carbon/cerium oxide, and oxide graphene /activated carbon/aluminum hydroxide were obtained 0.973, 0.986 and 0.9994, respectively. The synthesized nanocomposites from cerium oxide and aluminum hydroxide nanoparticles showed good performance in removing safranin dye as compared to the blank sample (GO-AC).