title: Catalytic ozonation of organic pollutants from bio-treated dyeing and finishing wastewater using recycled waste iron shavings as a catalyst: Removal and pathways.
abstract: Catalytic ozonation of organic pollutants from actual bio-treated dyeing and finishing wastewater (BDFW) with iron shavings was investigated. Catalytic ozonation effectively removed organic pollutants at initial pH values of 7.18-7.52, and the chemical oxygen demand (COD) level decreased from 142 to 70 mg·L(-1) with a discharge limitation of 80 mg·L(-1). A total of 100% and 42% of the proteins and polysaccharides, respectively, were removed with a decrease in their contribution to the soluble COD from 76% to 41%. Among the 218 organic species detected by liquid chromatography-mass spectrometry, 58, 77, 79 and 4 species were completely removed, partially removed, increased and newly generated, respectively. Species including textile auxiliaries and dye intermediates were detected by gas chromatography-mass spectrometry. The inhibitory effect decreased from 51% to 33%, suggesting a reduction in the acute toxicity. The enhanced effect was due to hydroxyl radical (OH) oxidation, co-precipitation and oxidation by other oxidants. The proteins were removed by OH oxidation (6%), by direct ozonation, co-precipitation and oxidation by other oxidants (94%). The corresponding values for polysaccharides were 21% and 21%, respectively. In addition, the iron shavings behaved well in successive runs. These results indicated that the process was favorable for engineering applications for removal of organic pollutants from BDFW.
authors: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.
authors: Jin
authors: J
authors: Wu
authors: College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors: Luming
authors: L
authors: Ma
authors: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.
authors: Yunlu
authors: Y
authors: Chen
authors: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.
authors: Yunqin
authors: Y
authors: Cheng
authors: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. Electronic address: liuyan@fudan.edu.cn.
authors: Yan
authors: Y
authors: Liu
authors: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.
authors: Xiaosong
authors: X
authors: Zha
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D002384:Catalysis; D011232:Chemical Precipitation; D002851:Chromatography, High Pressure Liquid; D004396:Coloring Agents / Q000737:chemistry*; D003343:Corrosion; D004578:Electron Spin Resonance Spectroscopy; D008401:Gas Chromatography-Mass Spectrometry; D007220:Industrial Waste / Q000032:analysis*; D007501:Iron / Q000737:chemistry*; D008970:Molecular Weight; D009930:Organic Chemicals / Q000302:isolation & purification*; D010126:Ozone / Q000737:chemistry*; D059027:Recycling; D013050:Spectrometry, Fluorescence; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; D007220:Industrial Waste; D007501:Iron; D009930:Organic Chemicals; D010126:Ozone; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Bio-treated dyeing and finishing wastewater; Catalytic ozonation; Effluent organic matter; Iron shaving; Removal pathway