Adsorption studies of arsenic on Mn-substituted iron oxyhydroxide

Lakshmipathiraj, P.; Narasimhan, B.R.V.; Prabhakar, S.; Raju, G Bhaskar

doi:10.1016/j.jcis.2006.09.024

Cited by 76 publications

(56 citation statements)

References 18 publications

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“…They have been widely used in the extraction of heavy metals from natural [6] and industrial sources [7], which has generated a great number of studies about mechanisms of surface interactions [8][9][10][11][12]. These minerals are common in environments with high availability of metal sulphides exposed to oxidizing conditions, as in acid sulphate soils, in the oxidation zone of mine tailings, or ore deposits [13,14].…”

Section: Introductionmentioning

confidence: 99%

Liberation of Adsorbed and Co-Precipitated Arsenic from Jarosite, Schwertmannite, Ferrihydrite, and Goethite in Seawater

2014

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Sea level rise is able to change the geochemical conditions in coastal systems. In these environments, transport of contaminants can be controlled by the stability and adsorption capacity of iron oxides. The behavior of adsorbed and co-precipitated arsenic in jarosite, schwertmannite, ferrihydrite, and goethite in sea water (common secondary minerals in coastal tailings) was investigated. The aim of the investigation was to establish As retention and transport under a marine flood scenario, which may occur due to climate change. Natural and synthetic minerals with co-precipitated and adsorbed As were contacted with seawater for 25 days. During this period As, Fe, Cl, SO 4 , and pH levels were constantly measured. The larger retention capability of samples with co-precipitated As, in relation with adsorbed As samples, reflects the different kinetics between diffusion, dissolution, and surface exchange processes. Ferrihydrite and schwertmannite showed good results in retaining arsenic, although schwertmannite holding capacity was enhanced due its buffering capacity, which prevented reductive dissolution throughout the experiment. Arsenic desorption from goethite could be understood in terms of ion exchange between oxides and electrolytes, due to the charge difference generated by a low point-of-zero-charge and the change in stability of surface complexes between synthesis conditions and natural media. OPEN ACCESSMinerals 2014, 4 604

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Section: Introductionmentioning

confidence: 99%

Liberation of Adsorbed and Co-Precipitated Arsenic from Jarosite, Schwertmannite, Ferrihydrite, and Goethite in Seawater

2014

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“…Diversos materiais baseados na presença de ferro têm sido empregados como adsorvente, devido principalmente à necessidade de pouco pré-tratamento químico da solução e por apresentarem vantagens, principalmente devidas à formação do complexo Fe:As muito estável. [4][5][6][7][8][9][10][11] Além dos materiais contendo ferro, uma série de outros materiais também tem sido utilizada na adsorção de arsênio como, por exemplo, zeolitas, 2 pasta de cimento Portland, 12 oxisol, 13 políme-ros contendo zircônio (IV), 14 cinzas, 15 sub-produtos da atividade agrícola. 16 Dentre estes materiais alternativos utilizados na adsorção de arsênio encontram-se a quitina e quitosana 17,18 e quitosana impregnada com íons molibdato.…”

Section: Introductionunclassified

Adsorção de arsênio(V) pela quitosana ferro - III reticulada

Fagundes¹,

Bachmann²,

Tomaz³

et al. 2008

Quím. Nova

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Recebido em 21/3/07; aceito em 17/12/07; publicado na web em 31/7/08 ADSORPTION OF ARSENIC(V) BY CROSSLINKED IRON-III-CHITOSAN. The removal of As(V) by a crosslinked iron(III)-chitosan adsorbent was evaluated under various conditions. The adsorption capacity of CH-FeCL was around 54 mg/g of As(V). The kinetics of adsorption obeys a pseudo-first-order model with rate constants equal to 0.022, 0.028, and 0.033 min -1 at 15, 25 and 35 o C respectively. Adsorption data were well described by the Langmuir model, although they could be modeled also by the Langmuir-Freundlich equation. The maximum adsorption capacity, calculated with the Langmuir model, was 127 mg g -1 of As(V). The inhibition by competing anions is dependant on their kind and valence.Keywords: crosslinked iron(III)-chitosan; arsenate; adsorption. INTRODUÇÃOAlgumas atividades humanas podem favorecer a disponibilização do arsênio presente no solo. 1 A presença de arsênio em água foi relacionada a dermatites, câncer de pele, problemas neurológicos, hepatomegalia, problemas cardíacos, cânceres internos e intoxicações.2 A Agência de Proteção Ambiental (EPA-US), dos Estados Unidos, baixou o limite regular de arsênio para água potável de 50 para 10 g L -1, sendo que a data limite para atingir tais níveis foi em janeiro de 2006. Como resultado desta nova norma, vários trabalhos estão sendo desenvolvidos com o enfoque em novas tecnologias para a redução dos níveis de arsênio, tais como melhoria do sistema de coagulação, sistemas de membrana e novos adsorventes. 3O processo de adsorção em fase sólida é uma alternativa para a remoção de compostos de arsênio. Diversos materiais baseados na presença de ferro têm sido empregados como adsorvente, devido principalmente à necessidade de pouco pré-tratamento químico da solução e por apresentarem vantagens, principalmente devidas à formação do complexo Fe:As muito estável. Com base no que foi mencionado acima, o complexo de quitosana-ferro reticulado (QTS-FeR) foi utilizado como adsorvente de As(V). Foram avaliados os efeitos de vários parâmetros sobre a capacidade de adsorção de As(V), entre os quais a quantidade de ferro no polímero, o pH e a temperatura das soluções de As(V), efeito salino, concentração e tipo de sal. Também foram estudadas a cinética de adsorção e a capacidade máxima de adsorção através da aplicação de modelos matemáticos de adsorção. PARTE EXPERIMENTAL Preparação e caracterização do polímero QTS-FeROs complexos foram preparados com a quitosana da Purifarma com grau de desacetilação de 83% e massa molecular de 165.000. Todos os outros reagentes foram de procedências Vetec e utilizados sem purificação prévia.Os complexos quitosana ferro(III)-reticulado (QTS-FeR) foram preparados e caracterizados de acordo com o descrito na literatura. Estudo de adsorção do As(V) (Métodos de banho) Estudo das isotermas de adsorçãoA adsorção do As(V) foi estudada através do método de banho, num sistema termostatizado, 25 ± 0,5 ºC. Neste experimento foram utilizados 25 mg dos diferentes QTS-FeR em 20 mL de solução de a...

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“…A low-cost ferruginous manganese ore can remove As(III) from groundwater without any preoxidation [6]. Mn-substituted iron oxyhydroxide was prepared by the oxidation of ferrous carbonate, and exhibited high removal efficiency for As(III) [7]. However, applications of these Fe-Mn-based adsorbents were complicated in large-scale treatments.…”

Section: Introductionmentioning

confidence: 99%

Fe–Mn binary oxide incorporated into diatomite as an adsorbent for arsenite removal: Preparation and evaluation

Chang

Liu

et al. 2009

Journal of Colloid and Interface Science

104

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a b s t r a c tFe-Mn binary oxide incorporated into diatomite (FMBO-diatomite) was prepared by a simple coating method, and exhibited high oxidation and adsorption ability for arsenite [As(III)]. After being incorporated by Fe-Mn binary oxide, the surface area of diatomite increased 36%, and the pore volume increased five times. The pH zpc of FMBO-diatomite was determined to be 8.1. These characteristics are responsible for the increased As(III) adsorption efficiency. The adsorption equilibria of As(III) on FMBO-diatomite were described well by a Langmuir isotherm model due to the homogeneous distribution of Fe-Mn binary oxide on a diatomite surface. As(III) was oxidized into As(V), and then adsorbed by FMBO-diatomite. The oxidation and adsorption efficiencies for As(III) depended deeply on the pH of solution. When the pH was raised to 8.1, the As(III) adsorption efficiency of FMBO-diatomite was almost equal to the As(III) oxidation efficiency. Silicate and phosphate had negative effects on As(III) adsorption. Also the influence of silicate and phosphate with the pH variation was different.

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Adsorption studies of arsenic on Mn-substituted iron oxyhydroxide

Cited by 76 publications

References 18 publications

Liberation of Adsorbed and Co-Precipitated Arsenic from Jarosite, Schwertmannite, Ferrihydrite, and Goethite in Seawater

Liberation of Adsorbed and Co-Precipitated Arsenic from Jarosite, Schwertmannite, Ferrihydrite, and Goethite in Seawater

Adsorção de arsênio(V) pela quitosana ferro - III reticulada

Fe–Mn binary oxide incorporated into diatomite as an adsorbent for arsenite removal: Preparation and evaluation

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