Electrochemical advanced oxidation process with simultaneous persulfate and hydrogen peroxide on-site generations for high salinity wastewater

Organic contaminant abatement via an upgraded electrochemical process is considered one of the most efficient techniques. Here, an electrochemical advanced oxidation process is developed, combining persulfate in situ electro-generation on the β-PbO2 anode and hydrogen peroxide in situ electro-generation on the carbon cathode using a tank reactor. The abatement ability of organic contaminants is evaluated by real H-acid wastewater. COD and color can be entirely removed at a cell voltage of 2.5 V. The strong oxidant power and mineralization are attributed to the significant amount of the on-site produced reactive species, e.g. 1O2, ·OH, and SO4·−. The β-PbO2 coated Ti anode exhibits excellent electro-activity for SO42− to S2O82−. The commercial carbon powder Vulcan XC-72R treated with H3PO4 solution exhibits good hydrogen peroxide selectivity in an acid medium. The application of the oxygen-depolarized electrode not only can produce hydrogen peroxide but also reduces cell voltage and energy consumption.