The chemistry of the hydrogen sulfide and iron sulfide systems in natural waters

Morse, John W.; Millero, Frank J.; Cornwell, Jeffrey C.; Rickard, David

doi:10.1016/0012-8252(87)90046-8

Cited by 620 publications

(384 citation statements)

References 176 publications

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“…There are two methods most widely applied for AVS and SEM extraction called the purge-and-trap method (Morse et al, 1987) and the diffusion method (van Griethuysen et al, 2002), respectively. Compared with the diffusion method, it is very laborious to use the purge-and-trap method to handle a large number of samples simultaneously: a lot of glassware, gas and space are required (Brouwer and Murphy, 1994).…”

Section: Methodsmentioning

confidence: 99%

Acid-volatile sulfide and simultaneously extracted metals in surface sediments of the southwestern coastal Laizhou Bay, Bohai Sea: Concentrations, spatial distributions and the indication of heavy metal pollution status

Zhuang

Gao

2013

Marine Pollution Bulletin

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a b s t r a c tSurface sediments were collected from the coastal waters of southwestern Laizhou Bay and the rivers it connects with during summer and autumn 2012. The acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) were measured to assess the sediment quality. The results showed that not all sediments with [SEM]-[AVS] > 0 were capable of causing toxicity because the organic carbon is also an important metal-binding phase in sediments. Suppose the sediments had not been disturbed and the criteria of US Environmental Protection Agency had been followed, heavy metals in this area had no adverse biological effects in both seasons except for few riverine samples. The major ingredient of SEM was Zn, whereas the contribution of Cd -the most toxic metal studied -to SEM was <1%. The distributions of AVS and SEM in riverine sediments were more easily affected by anthropogenic activity compared with those in marine sediments.

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Section: Methodsmentioning

confidence: 99%

Acid-volatile sulfide and simultaneously extracted metals in surface sediments of the southwestern coastal Laizhou Bay, Bohai Sea: Concentrations, spatial distributions and the indication of heavy metal pollution status

Zhuang

Gao

2013

Marine Pollution Bulletin

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“…A resposta apresentada pelo eletrodo de platina é, na realidade, dada pelo par S n 2-/S 0 , termodinamicamente reversível. Isto explica a correlação verificada somente no trecho mais contaminado, entre os reservatórios de Pirapora e Barra Bonita, devido à presença de S 0 e, conseqüentemente, de polissulfetos, cuja formação é sugerida a partir das seguintes reações: 28 Fe …”

Section: Estudo Biogeoquímico Dos Sedimentos: Sulfetos Matéria Orgânunclassified

Extração seletiva de metais pesados em sedimentos de fundo do Rio Tietê, São Paulo

Bevilacqua

Silva²,

Lichtig³

et al. 2009

Quím. Nova

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Recebido em 24/10/07; aceito em 13/8/08; publicado na web em 20/1/09 SELECTIVE EXTRACTION OF HEAVY METALS IN BOTTOM SEDIMENTS FROM TIETÊ RIVER, SÃO PAULO. Sediment samples from Tietê river were submitted to chemical and sequential extractions of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn). It was followed a single extraction by using 0.1 mol L -1 hydrochloric acid and a sequential procedure to evaluate possible chemical associations described as exchangeable, carbonate, reducible oxides, sulfide, organic matter and residual fractions. High concentrations of heavy metals were determined at Pirapora reservoir, which is closer to the Metropolitan Area of São Paulo while for Barra Bonita reservoir, the results showed low concentrations for such elements. Acid volatile sulfides, grain size distribution and carbon contents were also determined.Keywords: heavy metals; sediment; chemical and sequential extractions. introduçãoHá pelo menos 3 décadas, os sedimentos já não têm sido considerados somente ambientes de deposição de espécies químicas, mas um compartimento aquático ativo que desempenha um papel fundamental na redistribuição dessas espécies à biota aquática. 1 Os processos naturais de formação de sedimentos vêm sendo intensamente alterados pela ação do homem. A erosão do solo causada pela construção de prédios e rodovias, bem como o lançamento direto de efluentes industriais e municipais têm propiciado um perfil significativamente diferente daqueles verificados em ambientes naturais não impactados. 2 Nesse contexto, uma atenção especial deve ser dada aos metais pesados, que não são naturalmente degradados, nem mesmo permanentemente fixados pelos sedimentos, podendo assim retornar à coluna d'água através de alterações de suas propriedades físico-químicas, tais como pH e potencial redox. 3 Sob condições operacionais definidas, os métodos analíticos de extração seqüencial têm sido aplicados com a proposta de se avaliar a distribuição dos metais nas diferentes formas que compõem o sedimento, tendo em vista o comportamento, a reatividade e o destino dessas espécies nos ambientes aquáticos. 3 Os métodos de extração seqüencial consistem em submeter uma determinada amostra de sedimento sob condições de extração em etapas cada vez mais enérgicas (tipos de reagentes, concentração, tempo e temperatura). As frações obtidas dizem respeito à proporção do metal que está associada a uma referida fase geoquímica. .Kersten e Förstner 4,5 desenvolveram um método de extração seqüencial que foi aplicado num estudo dos sedimentos do Rio Elba, altamente impactados, cujas frações foram definidas como trocáveis, metais ligados a carbonatos, metais associados aos óxidos facilmente redutíveis, metais associados aos óxidos moderadamente redutíveis e residual.Alguns problemas têm sido apontados aos métodos de extração seqüencial, tais como possíveis redistribuições do metal entre fases, seletividade dos reagentes, além da falta de concordância entre os resultados, principalmente para sedimentos anóxidos. 5,6 Embora os métodos de extração aprese...

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“…Primary magnetization carried by pyrrhotite has been reported in sediments [14] although sedimentologists usually found that the stable authigenic sulfides are restricted to pyrite (FeS2), mackinawite (FeSl_x) and greigite (Fe3S4) [15] among which only greigite is ferrimagnetic [1]. Indeed pyrrhotite is more typical of later evolution, such as the decay of the less stable authigenic sulfide into pyrite and pyrrhotite.…”

Section: Occurrence Of Pyrrhotite In Rocksmentioning

confidence: 99%

Magnetic transition at 30–34 Kelvin in pyrrhotite: insight into a widespread occurrence of this mineral in rocks

Rochette

Fillion

Mattéi

et al. 1990

Earth and Planetary Science Letters

273

175

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A characteristic magnetic transition at 30-34 K is shown to provide a powerful tool for the identification of pyrrhotite with concentration down to 10 ppm through the same low-temperature techniques as applied to magnetite and hematite, extended down to liquid helium temperature. A review of rock magnetic and petrological data on pyrrhotite suggests that this mineral should be considered as a major carrier of paleomagnetic signals. Unblocking temperature up to 350 °C and extreme resistance against AF may be encountered in fine grained pyrrhotite.

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The chemistry of the hydrogen sulfide and iron sulfide systems in natural waters

Cited by 620 publications

References 176 publications

Acid-volatile sulfide and simultaneously extracted metals in surface sediments of the southwestern coastal Laizhou Bay, Bohai Sea: Concentrations, spatial distributions and the indication of heavy metal pollution status

Acid-volatile sulfide and simultaneously extracted metals in surface sediments of the southwestern coastal Laizhou Bay, Bohai Sea: Concentrations, spatial distributions and the indication of heavy metal pollution status

Extração seletiva de metais pesados em sedimentos de fundo do Rio Tietê, São Paulo

Magnetic transition at 30–34 Kelvin in pyrrhotite: insight into a widespread occurrence of this mineral in rocks

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