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 removal of triclosan via peroxymonosulfate activated by a ppb level dosage of Co(II) in water: Reaction kinetics, mechanisms and detoxification.
Jianbiao Peng,Chaonan Zhang,Yaozong Zhang,Shuai Shao,Pingping Wang,Guoguang Liu,Hang Dong,Dexin Liu,Jialu Shi,Zhiguo Cao,Haijin Liu,Shixiang Gao +11 more
TL;DR: This study systematically investigated the removal of TCS in aqueous solution via peroxymonosulfate (PMS) activated by an extremely low-level Co2+ (0.02 μM) and outlooks these findings to advance the feasibility of organic contaminants removal via Co 2+/PMS system with Co2- at extremely low levels.
Journal ArticleDOI
Oxidative degradation of ranitidine by UV and ultrasound: identification of transformation products using LC-Q-ToF-MS
TL;DR: In this paper, the authors analyzed the transformation products (TPs) formed from the degradation of Ranitidine in aqueous solution induced by three AOPs; namely, UV-photolysis, UV/peroxodisulfate (PDS), and sonolysis.
Journal ArticleDOI
Enhanced activation of peroxymonosulfate through exfoliated oxygen-doping graphitic carbon nitride for degradation of organic pollutants
TL;DR: Wang et al. as mentioned in this paper modified graphitic carbon nitride (g-C3N4) with oxygen atoms in the first step, then exfoliated via sequential thermal and ultrasound treatment to produce O-g-c3n4 nanoflakes to increase its catalytic activity to activate peroxymonosulfate.
Journal ArticleDOI
Comparison between Fenton and Fenton-like reactions for l-proline degradation
TL;DR: In this paper, Fe/H2O2 and Co/PMS reactions were compared for l-proline degradation under different initial pH values, various transition metal salt and oxidant agent concentrations, as well with and without irradiation.
Journal ArticleDOI
Influence of calcination temperature on the catalytic performance of Co3O4/GO nanocomposites for Orange II degradation
TL;DR: In this article, the catalysts were calcined at different temperatures of 300, 500, 700, and 900 °C for 2 hours in the N2 atmosphere and the catalytic activity of both uncalcined and calcined catalysts was studied at the same time.
References
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