Journal ArticleDOI
Cobalt-mediated activation of peroxymonosulfate and sulfate radical attack on phenolic compounds. implications of chloride ions.
TLDR
The sulfate radical pathway of the room-temperature degradation of two phenolic compounds in water is reported, and it provides strong evidence on the interaction of chloride ions with sulfate radicals leading to halogenation of organics in water.Abstract:
The sulfate radical pathway of the room-temperature degradation of two phenolic compounds in water is reported in this study. The sulfate radicals were produced by the cobalt-mediated decomposition of peroxymonosulfate (Oxone) in an aqueous homogeneous system. The major intermediates formed from the transformation of 2,4-dichlorophenol were 2,4,6-trichlorophenol, 2,3,5,6-tetrachloro-1,4-benzenediol, 1,1,3,3-tetrachloroacetone, pentachloroacetone, and carbon tetrachloride. Those resulting from the transformation of phenol in the presence of chloride ion were 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol, 1,1,3,3-tetrachloroacetone, and pentachloroacetone. In the absence of chloride ion, phenol transformed into 2,5-cyclohexadiene-1,4-dione (quinone), 1,2-benzenediol (catechol), and 1,4-benzenediol (hydroquinone). Several parameters were varied, and their impact on the transformation of the organic compounds is also discussed. The parameters varied were the initial concentration of the organic substrate, the dose of Oxone used, the cobalt counteranion, and in particular the impact of chloride ions and the quenching agent utilized for terminating the reaction. This is one of the very few studies dealing with intermediates formed via sulfate radical attack on phenolic compounds. It is also the first studythat explores the sulfate radical mechanism of oxidation, when sulfate radicals are generated via the Co/Oxone reagent. Furthermore, it provides strong evidence on the interaction of chloride ions with sulfate radicals leading to halogenation of organics in water.read more
Citations
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Journal ArticleDOI
Efficient decomplexation of heavy metal-EDTA complexes by Co2+/peroxymonosulfate process: The critical role of replacement mechanism
TL;DR: In this article, the decomplexation efficiency of various metal ion-catalyzed oxidation processes (MICOPs) has been investigated for the treatment of wastewater containing heavy metal complexes (HMCs).
Journal ArticleDOI
Degradation of tetrabromobisphenol A in heat activated persulfate oxidation process
TL;DR: Sulfate radicals generated by heat activated persulfate were employed to degrade brominated flame retardant tetrabromobisphenol A (TBBPA) as discussed by the authors.
Journal ArticleDOI
Efficient persulfate non-radical activation of electron-rich copper active sites induced by oxygen on graphitic carbon nitride
TL;DR: This work demonstrates that the formation of metastable intermediates and the initiation of effective non-radical reactions can be achieved by constructing differentiated electron density structures.
Journal ArticleDOI
Degradation of the nonionic surfactant Triton™ X-45 with HO and SO4- – Based advanced oxidation processes
TL;DR: In this article, the nonionic surfactant Triton ™ X-45 (TX-45), an octylphenol polyethoxylate, was treated by persulfate (S 2 O 8 2 - )/UV-C process involving the intermediacy of sulfate radicals and the relatively well-known hydrogen peroxide (H 2 O 2 /UV-c) process.
Journal ArticleDOI
Chlorine incorporation into dye degradation by-product (coumarin) in UV/peroxymonosulfate process: A negative case of end-of-pipe treatment.
Ying Huang,Bo Sheng,Fei Yang,Zhaohui Wang,Zhaohui Wang,Yizhen Tang,Qingze Liu,Xiaoxiao Wang,Jianshe Liu +8 more
TL;DR: A negative case of UV/PMS for the treatment of one of secondary degradation byproducts of dyes (coumarin, COU) is demonstrated, highlighting the imperativeness of minimizing auxiliary salt dosages in dyeing processes and developing new end-of-pipe technologies that can work in a saline environment.
References
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