Sequential reduction–oxidation for photocatalytic degradation of tetrabromobisphenol A: Kinetics and intermediates

Guo, Yaoguang; Lou, Xiaoyi; Xiao, Dongxue; Xu, Lei; Wang, Zhaohui; Liu, Jianshe

doi:10.1016/j.jhazmat.2012.09.044

Cited by 55 publications

(20 citation statements)

References 24 publications

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“…Figure 3B shows that the reaction rate increased significantly with increasing pH at pH values higher than the compound pKa, whereas it did not greatly increase at pH values lower than the compound pKa. These results show that at pH values below its pKa, the quantum yield of TBBPA photodecomposition decreases with decreasing pH, whereas at pH values above its pKa, photodecomposition is independent of pH (Eriksson at al., 2004); they also show that the TBBPA degradation and debromination rates increase sharply with increasing pH at pH values higher than the compound pKa, as previously suggested by several researchers (Guo et al, 2012;Zhang et al, 2009;Miyamoto et al, 2014). Figure 4 shows the effect of the irradiation intensity on the rate of 2,6-DBSQ  generation under ambient-(2.8 W m −2 ) and visible-light (950 W m −2 ) conditions.…”

Section: Effect Of Ph On 26-dbsq  Formationsupporting

confidence: 71%

Photodecomposition of tetrabromobisphenol A in aqueous humic acid suspension by irradiation with light of various wavelengths

2016

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The reactive species generated in aqueous 3,3',5,5'-tetrabromobisphenol A (TBBPA)/humic acid (HA) suspensions above the TBBPA pKa (∼7.4), under various light-irradiation conditions, namely ambient and ultraviolet light, were investigated using electron paramagnetic resonance (EPR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS). We confirmed that singlet oxygen and OH radicals are the key reactive oxygen species generated at wavelengths greater than 400 and 300 nm, respectively. The amount of 2,6-dibromo-p-benzosemiquinone anion radicals (2,6-DBSQ(•-)) formed under irradiation at 400 nm increased linearly with respect to irradiation time; the initial reaction rate was 7.03 × 10(-9) mol g(-1) HA s(-1). The rate increased with increasing pH and light intensity. LC-MS and EPR spectroscopy showed that tribromohydroxybisphenol A was formed under irradiation at 300 nm via reaction of OH radicals with TBBPA. This study, for the first time, shows that the main byproducts formed during irradiation at wavelengths above 300 nm are 2,6-DBSQ(•-) and tribromohydroxybisphenol A, generated from singlet oxygen ((1)O2) and OH radicals, respectively. Photodecomposition of TBBPA in the environment may occur by formation of (1)O2 and OH radicals.

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Section: Effect Of Ph On 26-dbsq  Formationsupporting

confidence: 71%

Photodecomposition of tetrabromobisphenol A in aqueous humic acid suspension by irradiation with light of various wavelengths

2016

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“…In other photodecomposition experiments, direct UV photolysis of 0.10 mM TBBPA under alkaline conditions led to 90 decomposition after 240 min 20 . In contrast, in the case of photocatalytic TiO 2 oxidation, TBBPA 10 mg L 1 ; alkaline media; 100 mL was decomposed by approximately 50 after 60 min of UV irradiation 21 . In the catalytic method, an aqueous solution of 0.072 mM TBBPA was 100 decomposed within about 50 min in the presence of the Pd 1.9 wt.…”

Section: Degradation Of Tetrabromobisphenol-amentioning

confidence: 93%

Enhanced Degradation of Organic Pollutants with Microwave-induced Plasma-in-liquid (MPL): Case of Flame Retardant Tetrabromobisphenol-A in Alkaline Aqueous Media

et al. 2020

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Introduction One of the first applications of advanced oxidation processes AOPs was reported in 1987 by Glaze 1 , who proposed that such processes involve the generation of OH in sufficient quantity to affect water purification. Several AOPs have been described since, many of which involve use of the powerful oxidizing hydroxyl radical OH that can oxidize and degrade organic pollutants from contaminated air and polluted aqueous ecosystems. These AOPs are termed advanced, because the chemical reactions are essentially the same except that they occur considerably faster billions of times vis-à-vis reactions that occur if the pollutants were exposed solely to a natural environment 2. Other AOPs include UV/O 3 , UV/H 2 O 2 , Fenton, photo-Fenton, non-thermal plasmas, sonolysis, photocatalysis, radiolysis, and supercritical water oxidation processes 3 7. However, newer approaches to achieve advanced oxidation

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“…The absorption of a photon with energy larger than the band gap of TiO 2 can excite an electron from the valence band to the conduction band thus producing reductive conduction band electrons and oxidative valence band holes [18]. The holes can react with adsorbed water to produce OH radicals or directly oxidize adsorbed organic pollutants to their radicals.…”

Section: Effects Of Oxygen On Photodegradationmentioning

confidence: 99%

In Situ ATR-FTIR Investigation of Photodegradation of 3,4-Dihydroxybenzoic Acid on TiO2

Bürgi

2016

Catal Lett

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Sequential reduction–oxidation for photocatalytic degradation of tetrabromobisphenol A: Kinetics and intermediates

Cited by 55 publications

References 24 publications

Photodecomposition of tetrabromobisphenol A in aqueous humic acid suspension by irradiation with light of various wavelengths

Photodecomposition of tetrabromobisphenol A in aqueous humic acid suspension by irradiation with light of various wavelengths

Enhanced Degradation of Organic Pollutants with Microwave-induced Plasma-in-liquid (MPL): Case of Flame Retardant Tetrabromobisphenol-A in Alkaline Aqueous Media

In Situ ATR-FTIR Investigation of Photodegradation of 3,4-Dihydroxybenzoic Acid on TiO2

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