Electrochemical removal of rhodamine 6G by using RuO₂ coated Ti DSA

In this study, electrochemical removal of rhodamine 6G containing wastewater using RuO₂-coated Ti mesh as dimensionally stable anode is investigated. The effects of pH, supporting electrolyte, electrolyte concentration, applied current, and distance between electrodes on the removal efficiency were examined in a batch reactor. It is shown that NaCl is the best supporting electrolyte among NaCl, Na₂SO₄, NaClO ₄, and NaNO₃. Lower solution pH and higher concentration of supporting electrolyte facilitate the treatment process. Small distance between electrodes greatly decreases the energy consumption. The decolorization efficiency of above 99.5% and the low energy consumption of 1.58 kWh/m ³ can be achieved under the optimized experimental condition of NaCl concentration of 0.2 M, applied current of 1.0-1.9 A, pH < 6, and distance between electrode of 5 mm. The RuO2-coated Ti mesh anode is shown to have good recyclability and lifespan. A greater dye removal of 99.2% can be obtained by a continuous stirred-tank reactor with a HRT of 4 min. It is anticipated that the developed technology from this study can be further scaled up for full-scale treatment of industrial dye containing wastewater.