Assessment of Electrocoagulation Treatment of Textile Wastewater using Constant Voltage and Constant Current Modes: A Comparative Study

Abstract

A huge amount of textile wastewater is discharged every year from several industries that must be treated. This work aims to assess the ability of an electrocoagulation removal of Reactive Blue dye (RBD) from synthetic textile wastewater using plane-perforated aluminum electrodes connected in a bipolar connection. The kinetics of reaction and thermodynamic parameters have been studied. The effect of power supplied mode was investigated and compared using two modes; Constant Current Mode (CCM) (at 3 A) and Constant Voltage Mode (CVM) (at 20 volt) along the period of experiments (the electrolysis time: 2-70 min), and the pH was 8. The results obtained show that the removal efficiency of RBD using CCM was higher compared to that obtained in the case of CVM. After 70 min, the former technique provided 98.82% of RBD removal while the latter mode provided 97.74% of removal efficiency at the same condition of initial RBD concentration (100 ppm) and pH 8. Despite the slight difference between the two results obtained, this finding proved that the CCM was relatively more efficient and cost-effective than the CVM. The order of the CCM was a first-order while it was a second-order for the other mode. Moreover, both of these processes are endothermic.