[Advanced Treatment of Effluent from Industrial Park Wastewater Treatment Plant by Ferrous Ion Activated Sodium Persulfate].

Fe(II) activated sodium persulfate (PS) technology was used for advanced treatment of effluent from industrial park wastewater treatment plant. Separate and combined effects of PS/COD, Fe(II)/PS and pH on COD and TOC removal were analyzed by the response surface methodology. Variations of organic substances before and after Fe(II)-PS oxidation were characterized by UV-Vis spectrometry, gel chromatography and three-dimensional fluorescence. PS/COD and Fe(II)/PS had significant effect on COD removal, while all the three factors had significant effect on TOC removal. The combined effect of PS/COD and pH had significant effect on COD removal. COD and TOC removal efficiencies reached 50.7% and 60.6% under optimized conditions of PS/COD 3.47, Fe(II)/PS 3.32 and pH 6.5. Fe(II)-PS oxidation converted macromolecular organic substances to small ones, and reduced contents of protein-, humic- and fulvic-like substances.