Electrochemical treatment of highly coloured textile wastewater: Optimization through experimental design

Abstract

The main goal of this study was to treat highly coloured textile wastewater (HCTW) by electrocoagulation (EC) due to its environmental hazard. The experiments were carried out in batch mode using an electrolytic cell in which the electrodes are arranged in a parallel monopolar configuration. The results of HCTW's characterization showed that these wastewaters are poorly biodegradable (BOD5/ COD = 0.07) and have a relatively high organic load (COD = 1024.6 mg/L). Modelling of the treatment using a full factorial design (FFD) showed firstly that the three selected factors electrolysis time ( 1 ), current intensity ( 2 ) and electrode type ( 3 ) are statically significant. The increase in electrolysis time ( 1 ) and current intensity ( 2 ) has a positive effect on the removal of absorbance and COD. Moreover, iron electrodes have a better efficiency compared to aluminium electrodes. In addition, they promote increased mass loss. Secondly, the optimal conditions were determined from a composite central design (CCD). The criteria for multi-objective optimization of mathematical models were to maximize the removal of absorbance and COD while minimizing mass loss. The application of the predicted optimal Electrochemical … Sié Alain Hien et al.