Catalytic ozonation of emerging pollutant and reduction of toxic by-products in secondary effluent matrix and effluent organic matter reaction activity. (1st December 2019)

• Record Type: Journal Article
• Authors: Zhang, Yuting; An, Yechen; Liu, Chao; Wang, Yiping; Song, Zilong; Li, Yanning; Meng, Weidong; Qi, Fei; Xu, Bingbing; Croue, Jean-Philippe; Yuan, Donghai; Ikhlaq, Amir
• Is Part Of: Water research. Volume 166(2019)
• Publication Date: 2019-12-01
• Subjects: Benzotriazole -- Catalytic ozonation -- Disinfection by-products -- Effluent organic matter -- Two-dimensional correlation spectroscopy; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2019.115026
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: In this study, the performance of LaCoO3 (LCO) catalytic ozonation was evaluated comprehensively, including the degradation efficiency of benzotriazole (BZA) as a typical emerging pollutant, toxic bromate reduction and the disinfection by-products (DBPs) precursors removal ability in effluent organic matter (EfOM), as well as EfOM reactive activity in catalytic ozonation. Additionally, the reduction of toxic halogenated by-products in (catalytic) ozonation was reported, which was not focused on previous researches before. Results showed that LCO catalytic ozonation improved the removal efficiency of BZA, UV254 and SUVA via enhanced HO· formation. Interestingly, LCO catalytic ozonation showed the ability on the reduction of aldehydes and toxic halogenated organic by-products. Moreover, the formed [trichloromethane (TCM)], [bromochloroacetonitrile (BCAN)] and [dichloroacetamide (DCAcAm)] decreased significantly in catalytic ozonation. Catalytic ozonation was also able to remove DBPs precursors to decline the formation of DBPs, such as TCM, bromodichloromethane (BDCM), trichloroacetonitrile (TCAN) and trichloronitromethane (TCNM). This process was involved in the transformation of EfOM in catalytic ozonation, which was confirmed by multi-spectrum methods, two-dimensional correlation spectroscopy (2D-COS) and hetero-spectral 2D-COS. In summary, LCO was shown to be an effective catalyst to improve the performance of the sole ozonation on the removal of emerging contaminants and DBPs precursors, as well as toxic by-products reduction. Additionally, the strategy of toxic by-products reduction in catalytic ozonation was proposed. Results indicated this technology was an important contribution on removal of refractory organics and formation of toxic by-products in water supply and wastewater treatment industry. Graphical abstract: Image 1 Highlights: LaCoO3 enhanced the ozonation of emerging pollutant and DBPs precursor. LaCoO3 showed the ability on the reduction of toxicity by-products in ozonation. The 2D-COS and hetero-spectral one proved the transformation pathway of EfOM. DBP precursor degradation was due to the structure variation of EfOM in ozonation.