Photochemical decomposition of environmentally persistent short-chain perfluorocarboxylic acids in water mediated by iron(II)/(III) redox reactions

Hori, Hisao; Yamamoto, Ari; Koike, Kazuhide; Kutsuna, Shuzo; Osaka, Issey; Arakawa, Ryuichi

doi:10.1016/j.chemosphere.2006.12.038

Cited by 92 publications

(42 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The amount of Fe 2+ after 4 h reaction was about 0.4% of the initial amount of Fe 3+ (50 M), which implied that PFOA also could be photochemically decomposed in a similar way in the presence of ferric ion. Hori et al [28] also reported that about 0.7% of the initial amount of Fe 3+ (5.0 mM) was transformed to Fe 2+ after 24 h reaction under oxygen atmosphere during the photochemical degradation of perfluoropentanoic acid. And they supposed that the complex between Fe 3+ and C 2 F 5 COOH was a prerequisite species for the photochemical degradation of C 2 F 5 COOH under 220-460 nm light according to ESR spectrum of the mixture solution of iron (III) sulfate and C 2 F 5 COOH.…”

Section: Decomposition Mechanism Of Pfoamentioning

confidence: 98%

See 1 more Smart Citation

Ferric ion mediated photochemical decomposition of perfluorooctanoic acid (PFOA) by 254nm UV light

Wang

Zhang

Pan

et al. 2008

Journal of Hazardous Materials

150

View full text Add to dashboard Cite

a b s t r a c tThe great enhancement of ferric ion on the photochemical decomposition of environmentally persistent perfluorooctanoic acid (PFOA) under 254 nm UV light was reported. In the presence of 10 M ferric ion, 47.3% of initial PFOA (48 M) was decomposed and the defluorination ratio reached 15.4% within 4 h reaction time. While the degradation and defluorination ratio greatly increased to 80.2% and 47.8%, respectively, when ferric ion concentration increased to 80 M, and the corresponding half-life was shortened to 103 min. Though the decomposition rate was significantly lowered under nitrogen atmosphere, PFOA was efficiently decomposed too. Other metal ions like Cu 2+ and Zn 2+ also slightly improved the photochemical decomposition of PFOA under irradiation of 254 nm UV light. Besides fluoride ion, other intermediates during PFOA decomposition including formic acid and five shorter-chain perfluorinated carboxylic acids (PFCAs) with C7, C6, C5, C4 and C3, respectively, were identified and quantified by IC or LC/MS. The mixture of PFOA and ferric ion had strong absorption around 280 nm. It is proposed that PFOA coordinates with ferric ion to form a complex, and its excitation by 254 nm UV light leads to the decomposition of PFOA in a stepwise way.

show abstract

Section: Decomposition Mechanism Of Pfoamentioning

confidence: 98%

“…Many studies indicated the existence of ferric ion improved the degradation of organic pollutants. Although Hori et al [28] recently reported that photochemical decomposition of shortchain (C 3 -C 5 ) PFCAs were induced by Fe 3+ with 220-460 nm light under rigorous conditions, i.e. pressure 0.49 MPa and pH 1.5.…”

Section: Introductionmentioning

confidence: 99%

Ferric ion mediated photochemical decomposition of perfluorooctanoic acid (PFOA) by 254nm UV light

Wang

Zhang

Pan

et al. 2008

Journal of Hazardous Materials

150

View full text Add to dashboard Cite

show abstract

“…The indirect photoreactions have been developed to improve the efficiency of photo degradation. Some oxidants, such as ozone (Lin et al, 2012a), persulfate (Hori et al, 2005) and ferric ion (Hori et al, 2007), have been found to enhance the degradation and mineralization of PFOA. However, these methods require chemical compounds that are potential secondary pollutants.…”

Section: Introductionmentioning

confidence: 99%

Temperature effect on photolysis decomposing of perfluorooctanoic acid

Zhang

Pan

Zhou

2016

Journal of Environmental Sciences

View full text Add to dashboard Cite

Perfluorooctanoic acid (PFOA) is recalcitrant to degrade and mineralize. Here, the effect of temperature on the photolytic decomposition of PFOA was investigated. The decomposition of PFOA was enhanced from 34% to 99% in 60 min of exposure when the temperature was increased from 25 to 85°C under UV light (201-600 nm). The limited degree of decomposition at 25°C was due to low quantum yield, which was increased by a factor of 12 at 85°C.Under the imposed conditions, the defluorination ratio increased from 8% at 25°C to 50% at 85°C in 60 min. Production of perfluorinated carboxylic acids (PFCAs, C7-C5), PFCAs (C4-C3) and TFA (trifluoroacetic acid, C2) accelerated and attained a maximum within 30 to 90 min at 85°C. However, these reactions did not occur at 25°C despite extended irradiation to 180 min. PFOA was decomposed in a step-wise process by surrendering one CF 2 unit. In each cyclical process, increased temperature enhanced the quantum yields of irradiation and reactions between water molecules and intermediates radicals. The energy consumption for removing each μmol of PFOA was reduced from 82.5 kJ at 25°C to 10.9 kJ at 85°C using photolysis. Photolysis coupled with heat achieved high rates of PFOA degradation and defluorination.

show abstract

“…It is possible that either PFOS intermediates are not stable in ZVI -H 2 O system or the ionization of the possible formed degradation products in the present aqueous solution is insufficient under negative electrospray ionization. It should be mentioned that in previous studies, where oxidation processes have been used for PFCs destruction, volatile unstable degradation products such as CHF 3 , CF 4 , were identified using GC-MS technique [10,12]. Such neutral polyfluorinated products aren't expected to be ionized and thus to be detectable by electrospray ionization.…”

Section: Mechanism Responsible For Pfos Removal By Mg-aminoclay Coatementioning

confidence: 99%

“…Hori et al [10] reported a removal of PFOA equal to 90 % (72 h irradiation), using direct photolysis under experimental conditions. Other studies have also found that persulfate and Fenton reagent can effectively degrade perfluorocarboxylic acids (PFCAs) to fluoride ions, carbon dioxide and shorter chain PFCAs [11][12][13]. Regarding the use of microsized ZVI, Hori et al [14] reported that PFOS can partially be degraded by elemental iron, Fe(0), in water under subcritical water conditions (> 250 o C) and high pressure (20 MPa).…”

Section: Introductionmentioning

confidence: 99%

Reductive degradation of perfluorinated compounds in water using Mg-aminoclay coated nanoscale zero valent iron

Hwang

Andersen

Stasinakis

et al. 2015

Chemical Engineering Journal

121

View full text Add to dashboard Cite

Photochemical decomposition of environmentally persistent short-chain perfluorocarboxylic acids in water mediated by iron(II)/(III) redox reactions

Cited by 92 publications

References 20 publications

Ferric ion mediated photochemical decomposition of perfluorooctanoic acid (PFOA) by 254nm UV light

Ferric ion mediated photochemical decomposition of perfluorooctanoic acid (PFOA) by 254nm UV light

Temperature effect on photolysis decomposing of perfluorooctanoic acid

Reductive degradation of perfluorinated compounds in water using Mg-aminoclay coated nanoscale zero valent iron

Contact Info

Product

Resources

About