Performance enhancement of electrochemical degradation of H-acid wastewater via novel membrane electrode assembly electrolyser

A membrane electrode assembly (MEA) based electrolyser is designed and fabricated for H-acid wastewater treatment and harmful chemical degradation. The electrochemical O₃ and H₂O₂ generation performance has been greatly enhanced owing to the nano PbO₂ catalyst on the anode and the PTFE/C catalyst on the cathode. Since the anode oxidation (AO) combined with oxygen reduction reaction (ORR) enhances ·OH radical generation, the in situ AO-ORR coupling system shows better mineralization efficiency and lower electrochemical energy consumption for organic degradation. Additionally, the nano PbO₂ anode exhibited excellent stability and maintained high degradation efficiencies after 15 times of successive reuse of the in situ AO-ORR coupling system. Based on 16 identified intermediates categorized as primary, secondary, and downstream intermediates, a possible degradation pathway of the H-acid electrochemical oxidation was proposed and the toxicity was drastically reduced after the degradation.