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
Iron–cobalt mixed oxide nanocatalysts: Heterogeneous peroxymonosulfate activation, cobalt leaching, and ferromagnetic properties for environmental applications
TL;DR: In this paper, a novel approach of using Fe-Co mixed oxide nanocatalysts for the heterogeneous activation of peroxymonosulfate (PMS) to generate sulfate radical-based advanced oxidation technologies (SR-AOTs) targeting the decomposition of 2,4-dichlorophenol, and especially focus on some synthesis parameters such as calcination temperature, Fe/Co contents, and TiO 2 support.
Journal ArticleDOI
Activation of Persulfates by Graphitized Nanodiamonds for Removal of Organic Compounds
Hongshin Lee,Hyoung Il Kim,Seunghyun Weon,Wonyong Choi,Yu Sik Hwang,Jiwon Seo,Chang Ha Lee,Jae-Hong Kim +7 more
TL;DR: Results indicate that radical intermediates such as sulfate radical anion and hydroxyl radical are not majorly responsible for this persulfate-driven oxidation of organic compounds, and suggest that G-ND plays a critical role in mediating facile electron transfer from phenol to persulfates.
Journal ArticleDOI
Comparison of sulfate and hydroxyl radical based advanced oxidation of phenol
TL;DR: In this article, the effect of initial oxidant concentration on photo-assisted persulfate (PS), hydrogen peroxide (H 2 O 2 ) and peroxymonosulfates (PMS) oxidation processes were evaluated and compared for aqueous phenol degradation.
Journal ArticleDOI
The mechanism of degradation of bisphenol A using the magnetically separable CuFe2O4/peroxymonosulfate heterogeneous oxidation process.
TL;DR: Surface-bound, rather than free radicals generated by a surface catalyzed-redox cycle involving both Fe(III) and Cu(II), are postulated to be responsible for the mineralization of bisphenol A.
Journal ArticleDOI
Oxidative removal of Bisphenol A by UV-C/peroxymonosulfate (PMS): Kinetics, influence of co-existing chemicals and degradation pathway
TL;DR: In this paper, a sulfate radical-based advanced oxidation process was applied for the degradation of an industrial chemical and suspected endocrine disruptor, Bisphenol A (BPA).
References
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Journal ArticleDOI
Rate Constants for Reactions of Inorganic Radicals in Aqueous Solution
TL;DR: In this article, rate constants have been compiled for reactions of various inorganic radicals produced by radiolysis or photolysis, as well as by other chemical means in aqueous solutions.
Journal ArticleDOI
Radical generation by the interaction of transition metals with common oxidants.
TL;DR: Nine transition metals were tested for the activation of three oxidants and the generation of inorganic radical species such as sulfate, peroxymonosulfate, and hydroxyl radicals to postulate the rate-determining step of the redox reactions taking place when a metal is coupled with an oxidant in aqueous solution.
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Degradation of organic contaminants in water with sulfate radicals generated by the conjunction of peroxymonosulfate with cobalt.
TL;DR: The advantage of Co/PMS compared to the traditional Fenton Reagent is attributed primarily to the oxidizing strength of the radicals formed, since sulfate radicals are stronger oxidants than hydroxyl and the thermodynamics of the transition-metal-oxidant coupling.
Journal ArticleDOI
Rate constants and mechanism of reaction of sulfate radical anion with aromatic compounds
TL;DR: In this paper, the exact rate constants for.SO/sub 4/sup -/ with substituted benzenes and benzoates have been determined by pulse radiolysis.
Journal ArticleDOI
Transition metal/UV-based advanced oxidation technologies for water decontamination
TL;DR: In this paper, the effect of ultraviolet (UV) light radiation and/or transition metals (M) for the activation of common oxidants (Ox) with the objective of treating recalcitrant organic contaminants in water was explored.