Pretreatment of phosphating wastewater with different advanced oxidation processes

The effects of three oxidation processes, ozone (O3) oxidation, O3/potassium peroxymonosulfate (PMS) oxidation, and O3/hydrogen peroxide (H2O2) oxidation, on the treatment of phosphating wastewater were compared. Additionally, the quality of effluent was analyzed through measurements of COD, UV254, and three-dimensional fluorescence spectra, highlighting the influence of various advanced oxidation processes on the wastewater effluent quality and the removal pathways. The results showed that increasing the ozone dosage and adding appropriate amounts of PMS and H2O2 could enhance the removal of organic contaminants from phosphating wastewater. With initial COD of (130±20) mg/L, reaction time of 120 minutes, and ozone dosage of 7.65 mg/min, the COD removal rate was only 37% by the ozonation process, the COD removal rate reached 45.65% by the O3/PMS oxidation process with PMS mass concentration of 2 g/L, the COD removal rate reached 58.3% by the O3/H2O2 oxidation process with 0.5 g/L dosage of H2O2 (30% concentra