Efficiency evaluation of the redox reaction using Fe(II)-g-C3N4 for the removal of hexavalent chromium from water

Fathi, Milad; Babapoor, Aziz; Rahimi-Ahar, Zohreh; Basharnavaz, Hadi

doi:10.24200/sci.2025.65934.9745

Efficiency evaluation of the redox reaction using Fe(II)-g-C3N4 for the removal of hexavalent chromium from water

Articles in Press

Document Type : Research Article

Authors

Milad Fathi ¹

Aziz Babapoor ¹

Zohreh Rahimi-Ahar ²

Hadi Basharnavaz ³

¹ Department of Chemical Engineering, University of Mohaghegh Ardabili, Ardabil, Iran

² Department of Chemical Engineering, Engineering Faculty, Velayat University, Iranshahr, Iran

³ Department of chemistry, University of Mohaghegh Ardabili, Ardabil, Iran Iran

10.24200/sci.2025.65934.9745

Abstract

Chromium (Cr) exists in various forms in surface water and groundwater. The high solubility and mobility of Cr(VI) make it a very hazardous material that pollutes water and soil ecosystems. In this study, Fe(II)-g-C₃N₄ was synthesized using melamine and FeCl₃.6H₂O via the thermal calcination method. Fe(II)-g-C₃N₄ was analyzed by XRD, FTIR, SEM, and DLS. It was shown that the g-C₃N₄ structure is a suitable distributor and stabilizer for iron particles. g-C₃N₄ reduced the accumulation of iron particles, increasing the efficiency of the redox reaction between Fe(II) and Cr(VI). The removal efficiency of Cr(VI) was influenced by pH, temperature, and the concentrations of Fe(II)-g-C₃N₄ and Cr(VI). Lower pH values, higher Fe(II)-g-C₃N₄ concentrations, and elevated temperature improved the k_obs and Cr(VI) elimination from water. Cr(VI) adsorption efficiency in the 30, 50, and 70 ppm solutions by Fe(II)-g-C₃N₄ nanoparticles was 99%, 93.9%, and 80.7%, respectively. Furthermore, the highest k_obs (0.0835 min^-1) was observed at a 30 ppm Cr(VI) concentration.

Keywords

Divalent iron

Graphitic carbon nitride

Redox

Hexavalent chromium

Separation

Subjects