De-colorization of Reactive Brilliant Orange X-GN by a novel rotating electrochemical disc process.

A novel electrochemical setup for wastewater treatment-rotating electrochemical disc process (RECDP) was developed in this article. The anode and cathode are distributed alternatively and evenly on a flat round disc, which was designed to improve mass transfer of organics from bulk solution to electrode surface, while at the same time increasing oxygen transfer from air to the liquid to benefit the organics oxidization. The color removal of dye Reactive Brilliant Orange X-GN (RBO) was experimentally investigated using the setup. The results show that the RECDP could efficiently remove the color by 99.5% after 60-min electrolysis. The influence of factors such as the disc rotating speed, current intensity, pH, and treating time was also explored, and the de-colorization mechanism was studied with electron paramagnetic resonance (EPR), UV-Vis, and IR. It has been confirmed that the free radicals oxidization leads to the dye de-coloration.