Dark and photoassisted iron(3+)-catalyzed degradation of chlorophenoxy herbicides by hydrogen peroxide

Pignatello, Joseph J.

doi:10.1021/es00029a012

Cited by 1,144 publications

(667 citation statements)

References 31 publications

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“…The technique consist in the use of iron-based catalysts which, in contact with hydrogen peroxide, and in the presence of light irradiation, produce highly oxidative radicals (HO • ) in aqueous solution 3 , leading to degradation of organic molecules. The iron-based catalysts can be directly used in the chemical reaction in the form of finely divided powders or immobilized on solid supports 4 .…”

Section: Introductionmentioning

confidence: 99%

Preparation of Mesoporous Fe2O3-Supported ZSM-5 Zeolites by Carbon-Templating and their Evaluation as Photo-Fenton Catalysts to Degrade Organic Pollutant

et al. 2016

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Mesoporous Fe 2 O 3 -supported ZSM-5 zeolites were prepared by carbon-templating and subsequently evaluated as photo-Fenton catalysts to degrade a dye used as a model heavy organic pollutant. The synthesis procedure of the mesoporous ZSM-5 zeolites was performed employing a nucleating gel and carbon particles as mesopores template. Thereafter, the precursor salt of the iron oxide (Fe 2 O 3 ) was impregnated and then calcined to obtain the final catalyst. For comparison purposes, a conventional Fe 2 O 3 -supported ZSM-5 zeolite was also prepared. The results showed that the amount of intracrystalline mesopores formed in the ZSM-5 crystals was influenced by the amount of carbon added into the synthesis mixture. In comparison to the conventional prepared catalyst, the mesoporous Fe 2 O 3 /ZSM-5 ones showed an improved performance in the degradation of the target organic pollutant by the photo-Fenton reaction, which was attributed to the improvement of their textural properties as consequence of the mesopores generation.

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Section: Introductionmentioning

confidence: 99%

Preparation of Mesoporous Fe2O3-Supported ZSM-5 Zeolites by Carbon-Templating and their Evaluation as Photo-Fenton Catalysts to Degrade Organic Pollutant

et al. 2016

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“…Chlorophenols are then oxidized by the combined action of OH· produced at the anode by means of reaction [4] and catalytic activity of PtO/PtO 2 (formation of polymers) and in homogeneous medium by means of Fenton reaction. Photo-electro-Fenton is a distinct method where contaminated solution is irradiated with UV light of λ=300-400nm that causes the photo-Fenton reaction of Fe(OH) +2 the predominant species of Fe +3 in acid medium, as is shown by equation [3] ( 22,23).…”

Section: Resultsmentioning

confidence: 99%

Micro Reactor For Chlorophenols Electrocathalytic Oxidation

Radovici¹,

Banu²

2009

ECS Trans.

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Chlorophenols are universal priority pollutants listed by all Environmental Agencies. The removal of chlorophenols from contaminated waters is carried out by microbiological and chemical methods. In this work is presented a combination of three methods that are electrochemical oxidation, electrochemical reduction and photo-Fenton-oxidation. Results performed in a micropilot reactor showed that it is feasible to degrade chlorophenols by these combined methods, with a removal rate of 82%, at a current density of 6.66 Adm -2 . The current efficiency was calculated and the results indicated that this combined method is more efficient that separated ones (electrochemical oxidation or reduction).

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“…Assim, a combinação do processo Fenton com irradiação, chamado processo foto-Fenton, aumenta a eficiência de oxidação, uma vez que regenera Fe(II) para a reação com H 2 O 2 , além de produzir radicais hidroxila adicionais. 55,68,69 (27) O pH do meio tem papel muito importante na eficiência dos processos Fenton e foto-Fenton. Valores acima de 3,0 fazem com que Fe(III) precipite na forma de hidróxido insolúvel, por outro lado, abaixo de 2,5 altas concentrações de H + podem seqüestrar radicais hidroxila (Equação 28), 69,70 além do predomínio de espécies menos hidroxiladas que apresentam menor absortividade, 55 sendo a necessidade de controle de pH a maior limitação destes processos.…”

Section: Fenton E Foto-fentonunclassified

“…55,68,69 (27) O pH do meio tem papel muito importante na eficiência dos processos Fenton e foto-Fenton. Valores acima de 3,0 fazem com que Fe(III) precipite na forma de hidróxido insolúvel, por outro lado, abaixo de 2,5 altas concentrações de H + podem seqüestrar radicais hidroxila (Equação 28), 69,70 além do predomínio de espécies menos hidroxiladas que apresentam menor absortividade, 55 sendo a necessidade de controle de pH a maior limitação destes processos. (28) A utilização de complexos policarboxilatos de Fe(III) tem se mostrado bastante interessante, considerando a estabilização do ferro em uma faixa mais ampla de pH.…”

Section: Fenton E Foto-fentonunclassified

“…71 O ferrioxalato de potássio apresenta absortividade máxima da ordem de 10 3 -10 4 L mol -1 L -1 no intervalo entre 200 e 480 nm, e alto rendimento quântico na formação de íons Fe 2+ , atingindo 1,24 em 300 nm, enquanto que a irradiação de hidroxo complexos tem rendimento de 0,14 em 313 nm. 54,69,72 Além disso, os radicais formados na fotólise do FeOx (Equações 29 a 31) podem colaborar para a oxidação de substâncias orgânicas.…”

Section: Fenton E Foto-fentonunclassified

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Degradação de fármacos residuais por processos oxidativos avançados

Melo¹,

Trovó²,

Bautitz³

et al. 2009

Quím. Nova

186

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DegraDação De fármacos resiDuais por processos oxiDativos avançaDos silene alessandra santos melo, alam gustavo trovó, ivonete rossi Bautitz e raquel fernandes pupo nogueira* Departamento de Química Analítica, Instituto de Química de Araraquara, Universidade Estadual Paulista, CP 355, 14801-970 Araraquara -SP, BrasilRecebido em 19/12/07; aceito em 17/7/08; publicado na web em 5/12/08 DEGRADATION OF RESIDUAL PHARMACEUTICALS BY ADVANCED OXIDATION PROCESSES. The concern about aquatic ecosystems and the potential risk of drinking water contamination by pharmaceuticals have stimulated the study of processes for the efficient degradation of these contaminants, since the conventional treatment have been inefficient on that purpose. The advanced oxidation processes (AOPs) appear as viable alternatives due to their efficiency on the degradation of different classes of organic contaminants. This review presents an overview of the main AOP (O 3 , H 2 O 2 /UV, TiO 2 /UV, Fenton and photo-Fenton) which have been applied to the degradation of different pharmaceuticals. The main results obtained, intermediates identified and toxicity data are presented.

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Dark and photoassisted iron(3+)-catalyzed degradation of chlorophenoxy herbicides by hydrogen peroxide

Cited by 1,144 publications

References 31 publications

Preparation of Mesoporous Fe2O3-Supported ZSM-5 Zeolites by Carbon-Templating and their Evaluation as Photo-Fenton Catalysts to Degrade Organic Pollutant

Preparation of Mesoporous Fe2O3-Supported ZSM-5 Zeolites by Carbon-Templating and their Evaluation as Photo-Fenton Catalysts to Degrade Organic Pollutant

Micro Reactor For Chlorophenols Electrocathalytic Oxidation

Degradação de fármacos residuais por processos oxidativos avançados

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