Comparative performance of anodic oxidation and electrocoagulation as clean processes for electrocatalytic degradation of diazo dye Acid Brown 14 in aqueous medium

In this study, a laboratory scale for the treatment of a recalcitrant and toxic synthetic wastewater containing diazo dye, acid brown 14 (AB-14) has been comparatively performed by two electro-catalytic treatment processes, namely anodic oxidation (AO) and electrocoagulation (EC) using a new batch electrochemical cell. Additionally, the influence of several operating parameters such as; current density (j), initial dye concentration (C-O), NaCI concentration (C-N), and pH on the color removal efficiency and chemical oxygen demand (COD) are evaluated. The powerful capability of the AO and'EC of AB-14 which related to the mechanistic reaction pathway is shown. The poor degradation is ascribed to higher Co and pH, while the enhancement of j and C-N is responsible for better degradation of AB-14 dye. The results indicate that the EC is more effective than AO under the same operational condition. A kinetic model is developed for evaluation of the pseudo-first-order-rate constant (k(app)) as a function of various operational parameters. The results emphasize the high efficiency of AO and EC and the clean processes which are hopeful alternative for the treatment of the large volume wastewater of the textile industry. (C) 2017 Elsevier B.V. All rights reserved.