Tangential-flow ultrafiltration: a versatile methodology for determination of complexation parameters in refractory organic matter from Brazilian water and soil samples

Romão, Luciane Pimenta Cruz; Castro, Gustavo Rocha de; Rosa, André Henrique; Rocha, Júlio César; Padilha, Pedro M.; Silva, H. C.

doi:10.1007/s00216-002-1728-6

Cited by 29 publications

(14 citation statements)

References 17 publications

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“…This step is necessary once metal species, in river water samples, may be found associated with organic substances existing in natural environment [33]. To do so, aliquots of 50 mL of water samples were first filtered in 45 m pore size membrane and then transferred to a beaker.…”

Section: Preparation Of the Natural Water Samplementioning

confidence: 99%

Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

Jorgetto

Silva

Saeki

et al. 2014

Applied Surface Science

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Section: Preparation Of the Natural Water Samplementioning

confidence: 99%

Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

Jorgetto

Silva

Saeki

et al. 2014

Applied Surface Science

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“…35,41,47 A possível sorção de metais na membrana, a separação por cargas, a necessidade de múltiplas coletas para capturar variações temporais das espécies e a alta demanda de tempo e constituem alguns dos pontos negativos da UF. 34,47,48 Além disso, a necessidade de armazenamento de água implica em mudanças (oxidação e/ou agregação) nas espécies originalmente presentes. 34 Entretanto, tem-se desenvolvido métodos para ultrafiltração e estudos de especiação on site, o que minimiza esses problemas.…”

Section: Particuladaunclassified

Metal and Metalloid Speciation in Aquatic Environments: Concepts, Techniques and Applications

Gontijo¹,

Monteiro²,

Rosa³

2017

Rev. Virtual Quim.

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Aquatic environments are dynamic systems, where metals and metalloids are continuously transformed and mobilised through different chemical forms among organic and inorganic substances and particulate material. These different forms of an element have different behaviours in a way that its total concentration provides just incomplete information related to mobility, bioavailability and toxicity. This work aimed to show the main features of the behaviour of metals and metalloids in aquatic environments and present the main techniques used in the investigation of chemical species and/or interactions with colloids and particulate material. Some of these techniques include filtration, ultrafiltration (UF), diffusive gradients in thin films (DGT), scanned deposition potential (SCP) and absence of gradients and nernstian equilibrium stripping (AGNES). Speciation and fractioning studies of water samples can indicate the potential bioavailability and mobility of metals and metalloids, especially when different techniques are used together.Keywords: Ultrafiltration; DGT; electrochemical techniques; trace metals; organic ligands. ResumoAmbientes aquáticos são sistemas dinâmicos, onde metais e metaloides transformam-se constantemente e são mobilizados em diferentes formas químicas na presença de substâncias orgânicas, inorgânicas e material particulado. Essas diferentes formas de um dado elemento possuem diversos comportamentos no ambiente, de modo que apenas a análise da sua concentração total fornece informações incompletas relativas a mobilidade, biodisponibilidade e toxicidade. Este trabalho teve como objetivos mostrar os principais aspectos do comportamento de metais e metaloides no meio aquático e apresentar algumas das principais técnicas utilizadas para estudo das suas espécies químicas e/ou interações com coloides e material particulado. Algumas dessas técnicas incluem filtração, ultrafiltração, difusão em filmes finos por gradientes de concentração (DGT), cronopotenciometria de redissolução anódica (SCP) e redissolução nernstiana na ausência de gradientes (AGNES). Estudos de especiação e fracionamento de amostras de água podem indicar a potencial biodisponibilidade e mobilidade de metais e metaloides, especialmente quando diferentes técnicas são aplicadas em conjunto.Palavras-chave: Ultrafiltração; DGT; técnicas eletroquímicas; metais-traço; ligantes orgânicos.

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“…The Scatchard model, which has been used in several previous studies [29][30], considers the complexation process described by Eq. (1) and the stability constant of the HS-N complex can be obtained using Eq.…”

Section: Complexation Capacity (Cc)mentioning

confidence: 99%

Investigations on the Thermodynamic Stability and Availability of Nutrients for Plants by Humic Substances Extracted from Peat Samples

Melo¹,

Oliveira²,

Cunha³

et al. 2015

JESE-A

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This work evaluated the complexation capacity, exchange constants and availability of micronutrients for plants and humic substances extracted from peat samples. Samples of humic substances extracted from two tropical peats (HS-P1 and HS-P2) were enriched with the micronutrients Cu(II), Co(II), Fe(II), Mn(II), Ni(II) and Zn(II) and the parameters for formation of the complexes (HS-N) were evaluated at different pH. The Scatchard model was used to calculate the maximum complexation capacity and the nutrient availability was studied using exchange capacity experiments based on ultrafiltration procedure. The optimum pH for complexation was 4.5 and the order of affinity was: Fe(II) > Cu(II) > Co(II) > Mn(II) = Ni(II) > Zn(II). The maximum complexation capacity reached 56.8 mg·g -1 Fe of HS-P1 (the highest) and 1.7 mg·g -1 Zn of HS-P2 (the slightest). The exchange experimentsshowed that HS-P-Fe complexes were formed preferentially. The least stable complex was formed with Zn, which was therefore, more easily available. The results contribute to understand the behavior and availability of some nutrients in soils.

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Tangential-flow ultrafiltration: a versatile methodology for determination of complexation parameters in refractory organic matter from Brazilian water and soil samples

Cited by 29 publications

References 17 publications

Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

Metal and Metalloid Speciation in Aquatic Environments: Concepts, Techniques and Applications

Investigations on the Thermodynamic Stability and Availability of Nutrients for Plants by Humic Substances Extracted from Peat Samples

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