Experimental Study on the Removal of Chromium (III) Ions Using Synthesized Reduced Graphene Oxide (RGO)

Abstract

Tanning industries release chromium-based effluents directly into the environment putting the whole ecosystem at risk. As a result, the wastewater must be properly treated before being released. Reduced Graphene oxide (RGO), a graphene material having adsorption capacity, is prepared, characterized, and applied to Chromium (III) effluent (synthetic effluent-SE) to determine its efficiency and adsorption capacity (AC). RGO was characterized by TGA, SEM images, XDR, and FTIR analysis. It was a well-developed adsorbent because of its high thermal stability, wrinkled topology, the disappearance of broad peak at 2-theta angle 10.049° present in GO, and the presence of oxygen-containing functional group respectively. A batch experiment has been carried out at different adsorbent doses, contact times, and pH on the effluent. About 90.31% removal efficiency was found within 10 minutes when the absorption capacity was 180.61mg/g. Therefore, isotherm and adsorption kinetics of chromium ions on the RGO surfaces were studied to understand the different aspects of adsorption capability. The result showed that the process was favourable for adsorption. RGO suggested monolayer adsorption because it followed the Langmuir Isotherm more closely than the Freundlich isotherm model. Additionally, it was more compatible with the intraparticle diffusion (IPD) and pseudo-second-order (PSO) models. The findings demonstrated that RGO has great potential as an adsorbent for efficiently and swiftly removing chromium ions from wastewater.