Pb 2+, Cu 2+and Cd 2+ ions uptake by Brazilian phosphate rocks

Mavropoulos, Elena; Rocha, Nilce C.C. da; Moreira, Josino Costa; Bertolino, Luíz Carlos; Rossi, Alexandre M.

doi:10.1590/s0103-50532005000100010

Cited by 25 publications

(11 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Ma et al (1994) reported that the presence of Cd, Fe and Cu only affect pyromorphite formation when in high concentrations. Mavropoulos et al (2005) show that the presence of Cu and Cd in aqueous solution does not interfere with the Pb-P phases formation, and the uptake of these elements by phosphate rock diminishes in presence of Pb. However, thermodynamic calculations (Porter et al 2004) indicate that Ca can inhibit Pb-P formation and for an efficient immobilization by P, excess of P needs to be available to react with all soluble Ca in soils.…”

Section: Formation Of Lead-phosphate Phasesmentioning

confidence: 89%

Lead Bioaccessibility in Soil and Mine Wastes After Immobilization with Phosphate

Bosso

Enzweiler

Angélica

2008

Water Air Soil Pollut

View full text Add to dashboard Cite

The immobilization of lead by the reaction with phosphate bearing materials is a promising remediation method for contaminated soils. Low soluble neo-formed lead-phosphate phases similar to chloropyromorphite [Pb 5 (PO 4 ) 3 Cl], can control availability and mobility of lead in the environment, and consequently reduce human exposure, if soils are the main contamination pathway. We used three phosphate source materials [NaH 2 (PO 4 ) 3 , commercial superphosphate and phosphate rock] to study lead immobilization in soil and mining waste samples. Products were examined after 1, 3 and 6 months of contact. The samples are from a contaminated area by former Pb mining and smelting activities, in southeastern Brazil, where epidemiological studies showed high lead blood levels in local population. The PBET (physiological based extraction test) bioaccessibility test was used to measure changes in the amount of soluble lead after sample treatment. Results show that the most efficient phosphate source was NaH 2 (PO 4 ) 3 , which reduced lead solubility to 92% in acidic gastric conditions after the first month of contact. Superphosphate and phosphate rock also diminished Pb solubility, but the effect was more time dependent. None specific Pb-phosphate phases could be identified by XRD in whole treated samples, but the PbCa-P elemental associations, observed on SEM images and EDS spectra of portions of the samples, combined with the reduced solubility, indicate that more insoluble lead phases were formed after the treatment. Based in these results, the in site phosphate application on soils to induce lead immobilization should be considered as a possible alternative to reduce human exposure at the area.

show abstract

Section: Formation Of Lead-phosphate Phasesmentioning

confidence: 89%

Lead Bioaccessibility in Soil and Mine Wastes After Immobilization with Phosphate

Bosso

Enzweiler

Angélica

2008

Water Air Soil Pollut

View full text Add to dashboard Cite

show abstract

“…12 Dessa forma, optou-se por utilizar as frações mais finas, cuja composição química é mostrada na Tabela 2.…”

Section: Como Esperado Os Phs Dos Dois Solos Variaram Após Os Tratamunclassified

“…Experimentos de sorção constataram que o Pb +2 em solução é principalmente imobilizado por frações mais finas da rocha. 12 Dessa forma, optouse por trabalhar com as frações mais finas, que possuem uma quantidade maior de apatitas.…”

unclassified

Estudo do comportamento do chumbo em latossolos brasileiros tratados com fosfatos: contribuições para a remediação de sítios contaminados

Kede¹,

Moreira²,

Mavropoulos³

et al. 2008

Quím. Nova

Self Cite

View full text Add to dashboard Cite

Recebido em 14/5/07; aceito em 17/8/07; publicado na web em 26/2/08 STUDY OF LEAD BEHAVIOUR IN BRAZILLIAN LATOSOILS TREATED WITH PHOSPHATES: CONTRIBUTIONS TO THE REMEDIATION OF CONTAMINATED SITES.Phosphates have been used for lead immobilization in soils but the influence of soil type is not fully understood. In this work, lead chemical behaviour in two Brazilian latosoils (LA and LV) was studied via treatment with phosphates. The Pb concentration in Toxicity Characteristic Leaching Procedure (TCLP) solutions was decreased in all treatments. After treatment with H 3 PO 4 the Pb concentration in the LA remained within the regulatory limit established by EPA. The ecotoxicological results with Daphnia pulex showed that this treatment reduced the lead bioavailability. Sequential extraction analyses showed that the lead was transferred from the most available to the residual fraction. Relevant decrease of soluble lead was observed in all phosphate treatments.Keywords: remediation; lead; phosphates. INTRODUÇÃOMetais tóxicos são encontrados naturalmente no solo, em baixas concentrações, como resultado do intemperismo e de outros processos pedogenéticos. Entretanto, as concentrações naturais podem ser modificadas por processos biogeoquímicos e, principalmente, pela ação antrópica. Dentre esses metais, o chumbo merece destaque devido a suas características toxicológicas e a seu tempo de permanência nos solos.1 Este elemento pode permanecer nos solos sob forma relativamente estável devido à baixa solubilidade de suas formas químicas, por adsorção em componentes naturais, 2 tais como a argila ou a matéria orgânica.No Brasil existem várias áreas contaminadas com chumbo com reflexos sobre a saúde da população local. No Vale do Ribeira, localizado no norte do Paraná e sul de São Paulo, foi constatada a contaminação por chumbo em crianças residentes nas vizinhanças da empresa Plumblum que beneficiava e refinava minérios de chumbo. Enquanto o limite máximo de chumbo no sangue de crianças recomendado pela Organização Mundial da Saúde (OMS) é de 10 µg dL No município de Santo Amaro da Purificação-BA, onde se encontram antigas instalações de outra filial da empresa Plumblum, foi constatada alta contaminação por chumbo em boa parte da população, no solo e nos sedimentos do rio Subaé. O uso de escória para aterros e para a construção de casas contribuiu para elevar a extensão da contaminação. Devido as suas propriedades bioquímico-fisiológicas sobre os organismos vivos, o chumbo quando incorporado ao ambiente ou aos organismos constitui ameaça à saúde do homem e dos ecossistemas. A maior parte dos casos de envenenamento por chumbo ocorre por ingestão oral e a absorção acontece no intestino. Uma vez absorvido, o chumbo é distribuído através do sangue para os diversos órgãos e sistemas e cerca de 90% se deposita nos ossos, onde substitui o cálcio. Esta absorção é maior em crianças que em adultos. 6As crianças são expostas ao chumbo por uma variedade de fontes ambientais, mas, fundamentalmente pelo hábito de levar a mão à boca. Os feto...

show abstract

“…All the standard solutions were prepared using deionized and twicedistilled water with specific conductance equal to (1.8 ± 0.1) μΩ -1 cm -1 . Ionic strength was adjusted to 0.1 mol dm -3 by addition of NaClO 4 .…”

Section: Chemicalsmentioning

confidence: 99%

“…3 The increasing rate of the environment pollution has stimulated worldwide research concerning new materials capable to remove heavy metal of cadmium(II) from contaminated soils and wastes. 4 Also, thallium has been recognized as a toxic element for many years. It produces a variety of adverse effects in human being.…”

Section: Introductionmentioning

confidence: 99%

Complexes of thallium(I) and cadmium(II) with dipeptides of L-phenylalanylglycine and Glycyl-L-phenylalanine

Sharifi¹,

Nori‐Shargh²,

Bahadory³

2007

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

As constantes de estabilidade dos complexos de íons tálio(I) e cádmio(II) com dipeptídeos de glicil-L-fenilalanina e L-fenilalanilglicina foram determinadas em solução aquosa a 25 °C e meio iônico 0,1 mol dm -3 usando uma combinação de técnicas potenciométricas e espectrofotométricas. Perclorato de sódio foi usado para manter a força iônica. A composição dos complexos formados foi determinada e observou-se que tálio (I) The stability constants of the complexes of thallium(I) and cadmium(II) ions with dipeptides of glycyl-L-phenylalanine and L-phenylalanylglycine were determined in aqueous solution at 25 °C and 0.1 mol dm -3 ionic medium using a combination of potentiometric and spectrophotometric techniques. Sodium perchlorate was used to maintain the ionic strength. The composition of the formed complexes was determined and it was shown that thallium(I) and cadmium (

show abstract

Pb 2+, Cu 2+and Cd 2+ ions uptake by Brazilian phosphate rocks

Cited by 25 publications

References 13 publications

Lead Bioaccessibility in Soil and Mine Wastes After Immobilization with Phosphate

Lead Bioaccessibility in Soil and Mine Wastes After Immobilization with Phosphate

Estudo do comportamento do chumbo em latossolos brasileiros tratados com fosfatos: contribuições para a remediação de sítios contaminados

Complexes of thallium(I) and cadmium(II) with dipeptides of L-phenylalanylglycine and Glycyl-L-phenylalanine

Contact Info

Product

Resources

About