A Comparison Between Aluminum and Iron Electrodes on Removal of Phosphate from Aqueous Solutions by Electrocoagulation Process

Document Type: Original Research Paper

Authors

1 Civil and Environmental Engineering Department, Amirkabir University of Technology (AUT), Hafez St., Tehran, 15875-4413, Iran

2 Textile Engineering Department, Amirkabir University of Technology (AUT), Hafez St., Tehran, 15875-4413, Iran

Abstract

This study presents a comparison between aluminum and iron plate electrodes on phosphate
removal from aqueous solutions by electrocoagulation process. The effectiveness of main operational parameters
such as initial pH, initial phosphate concentration and current density were examined. In addition, treated
solution and sludge characteristics, energy consumption and electrode mass depletion were compared for both
electrodes. All experiments were done in an electrocoagulation cell with effective volume of 2 liters. It was
found that the aluminum electrode has higher removal efficiency compared to the iron electrode in the same
operational conditions. Phosphate removal efficiencies of 100% and 84.7% were observed for aluminum and
iron electrode in a special case with optimum initial pH, maximum current density and maximum initial
phosphate concentration equal to 3, 250A/m2, 400mg/l PO4
3- , respectively. Furthermore, less treated solution
turbidity, higher secondary pollution (remained Al) and less electrode mass depletion was observed for the
aluminum electrode.

Keywords