Enhanced electro-oxidation/peroxone (in situ) process with a Ti-based nickel-antimony doped tin oxide anode for phenol degradation

Recently, a novel proof-of-concept oxygen reduction reaction (ORR) based electro-oxidation (EO) process has been developed, which was accomplished by integrating anodic electrochemical oxidation coupled with an in situ electro-peroxone process, by harnessing the anodic by-product O₃ reacted with ORR cathode generated H₂O₂. To further enhance EO coupled in situ electro-peroxone, a nickel and antimony doped tin oxide anodic catalyst layer, namely NATO, was fabricated on Ti mesh to improve anodic oxidation and reinforce the generation of O₃, thus promoting in situ Electro-peroxone. As a result, O₃ generation rate was enhanced by 12.6%. Complete phenol, as a model organic compound, and 95% of TOC removal were achieved, respectively, during ORR-EO. Through kinetics and instrument analysis, results show that the amount of intermediates accumulated during phenol degradation was much less in this Ti/NATO based ORR-EO system than in a traditional EO system. Moreover, 35.7% of the energy consumption was saved for ORR-EO, owing to its reduced applied voltage and the enhanced in situ electro-peroxone process.