Electrocoagulation process with Fe/Al electrodes to eliminate pollutants from real and synthetic wastewater

Abstract

This work investigated the effect of a victorious parameter of electrocoagulation (EC) on the removal of turbidity through batch reactor using Fe and Al electrodes. Synthetic (Sol 1, Sol 2) and natural wastewater (Sol 3) with different sodium chloride content were examined under different current densities (CD) and operating time. For the examined solutions conductivity, pH, total suspended solids (TSS) dissolved oxygen (DO) and energy consumption were measured. A novel approach examined the effect of solutions with selected operating parameters on Fe and Al corrosion using chemical and electrochemical tests. Using experimental data collected during the various parameters, a mathematical model of the electrocoagulation process was generated and assessed. FE-SEM images and EDX analyses for Fe and Al electrodes and XRD of coagulant particles, floc, generated by EC were also investigated. According to the findings, the ideal circumstances for the turbidity elimination from the examined solution were found to be as CD = 11 mA/cm2, pH ⁓ 7, and operating time = 20 min. Under these optimal circumstances, Al electrodes showed superior efficacy in removing than Fe electrodes for all examined solutions. The turbidity removal efficiency and the energy consumption were also found to be affected by NaCl content. The turbidity removal efficiencies reached their maximum value of 99 % for sol 3 where NaCl content was 3.45 × 10−1 M and energy consumption was 1.667 kWh/m3 by using Al anode.

Keywords

• Wastewater
• Electrocoagulation
• Sacrificial anodes
• Power consumption
• Experimental correlations
• Characterization