Electrochemical oxidation of Basic Blue 3 dye using a diamond anode: evaluation of colour, COD and toxicity removal

Abstract

BACKGROUND: Textile industries generate considerable amounts of waste-water, which may contain strong colour, suspended particles, salts, high pH and high chemical oxygen demand (COD) concentration. The disposal of these coloured wastewaters poses a major problem for the industry as well as a threat to the environment. In this study, electrochemical oxidation of Basic Blue 3 (BB3) dye was studied in a bipolar trickle tower (BTT) reactor using Raschig ring shaped boron-doped diamond (BDD) electrodes in recirculated batch mode. The effects of current density, temperature, flow rate, sodium sulfate concentration (Na 2 SO 4 ) as supporting electrolyte, and initial dye concentration were investigated.

Simultaneous removal of COD and NH3‐N in secondary effluent of high‐salinity industrial waste‐water by electrochemical oxidation

“…The efficiency of NH 3 -N and COD Cr removal is higher at higher applied current density. This result corroborates the findings of other studies, 22,25,27 and can be attributed to the increase in active chlorine generated by the increase in current density, which in turn enhances pollutant degradation.…”

Treatment of dairy industry wastewater by EC and EF processes using hybrid FeAl plate electrodes

“…It is well known that current density is one of the most important parameters affecting the performance of an electrochemical system 27, 28. The current supplied to the EC system determines the amount of Al 3+ or Fe 2+ ions released from the respective electrodes and the amount of resulting coagulants.…”

“…On the other hand, the current density applied to the electrochemical reactor is also directly proportional to the electrical energy consumption 27. An increase in the current density will also result in an increase in energy consumed per m 3 of treated wastewater.…”

Effect of the sp3/sp2 Ratio in Boron‐Doped Diamond Electrodes on the Degradation Pathway of Aniline by Anodic Oxidation

“…The interaction of the .OH radical with the BDD electrode is weak, and this is one of the reasons why Comninellis considers these electrodes as a non‐active anode. The main way to obtain this activity is by means of chemical vapor deposition (CVD), where different types of BDD electrodes have been obtained using different substrates materials such as titanium, niobium and silicon with different boron concentrations used to dope the surface, and recently, with different sp 3 /sp 2 carbon ratios . All these parameters could affect some properties of BDD such as the microstructure of the electrode .…”

“…OHÞ þ e À þ H þ (1) where BDD( * OH) indicates that the hydroxyl radical is weakly adsorbed onto the anode surface (BDD), allowing * OH to strongly react with all organic substances present in the electrolytic medium. The unselective (CVD), [33][34] where different types of BDD electrodes have been obtained using different substrates materials such as titanium, [35] niobium [36] and silicon [37] with different boron concentrations [38] used to dope the surface, and recently, with different sp 3 /sp 2 carbon ratios. [39] All these parameters could affect some properties of BDD such as the microstructure of the electrode.…”