Electrode performance via electrochemical treatment of textile wastewater: Analysis and characterization

Abstract

This study investigated a novel real-time thermodynamic diagnostic approach via current-interruption during active EC for track of the open circuit potential (OCP) during short current interruptions over the course of the experiment throughout the performance of a batch electrocoagulation reactor (BER) that using aluminum (Al)-iron (Fe) electrodes for the treatment of simulated wastewater containing a mixture of cation and anion dyes. The study considered various factors, including pH (2–10), current (0.6–1.4 A), concentration of dyes mixture (100–500 ppm), and electrolysis time (4–90 min). Surface response design process based on the central composite design (RSM-CCD) has been used to design the experiments and optimize the present operational parameters. The COD reduction, electrode consumption, open circuit potential (OCP), and energy consumption were predicted under the mentioned conditions with the aid of the analysis of variance (ANOVA). The optimization process was conducted to categorize the optimal conditions required to achieve the highest reduction of COD and minimum real consumption of energy and the anode electrode. The highest predicted reduction of COD of 94.57% vs. real removal of 88.9% under minimum consumption of energy and the anode electrode were obtained at the optimal conditions of 0.6 A, pH=7.98, 4 min, and the highest initial COD of 4236.7 ppm. XRD, FESEM, and FTIR tests were used for anode characterization. The main conclusion revealed that the finding of treating of wastewater that contains different types of dyes that could affect the performance of the electrocoagulation process. Also, the use of current-interruption during active EC to insight the thermodynamic oxidation ability of the anode reflects a complex interaction between the studied variables and response of the OCP of the anode during operation of EC.