Siderite dissolution in the presence of chromate

Tang, Yuanzhi; Martin, Scot T.

doi:10.1016/j.gca.2011.06.024

Cited by 20 publications

(13 citation statements)

References 51 publications

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“…The choice of low pH conditions in the range 1-5 is relevant for several environments such as leakage from oil and gas boreholes or acid mine drainage where arsenic and iron oxyhydroxides are observed (Benner et al, 1999;España et al, 2007) or even more extreme fluids with extremely low pH, as observed in an underground mine in California (Nordstrom et al, 2000). Our results complement previous studies where siderite dissolution was either measured in batch reactors (Golubev et al, 2009) or imaged using atomic force microscopy (Duckworth and Martin, 2004;Tang and Martin, 2011) and where adsorption of arsenic on iron oxyhydroxide was characterized (Dixit and Hering, 2003). These previous studies were limited in observing directly processes and measuring quantitative information on the rates of dissolution and precipitation at the nanoscale.…”

Section: Using Siderite To Remediate Polluted Waterssupporting

confidence: 80%

“…Atomic force microscopy images show that dissolution occurs by the formation and extension of rhombohedral etch pits, sometimes aligned along cleavage or fracture planes, and retreating of step edges (Duckworth and Martin, 2004;Tang and Martin, 2011). This is consistent with other carbonate mineral dissolution (see Ruiz-Agudo and Putnis (2012) for a review of AFM measurements and observations).…”

Section: Dissolution Of Sideritesupporting

confidence: 77%

“…Electron microscope images showed the formation of a 300 nm thick layer of iron oxides at the surface of the siderite grains (Guo et al, 2007a). Using X-ray photoelectron spectroscopy, it was confirmed that an iron hydroxide layer precipitated at the surface of siderite (Tang and Martin, 2011). All these studies show that dissolution of siderite and iron oxyhydroxide precipitation are coupled, and that iron oxyhydroxides can be used to sequester pollutants, such as arsenic.…”

Section: Using Siderite To Remediate Polluted Watersmentioning

confidence: 85%

“…Carbonate minerals dissolve with a rate that decreases from calcite to dolomite, siderite, and magnesite. The dissolution reaction of siderite under conditions relevant for natural environments, such as bottoms of lakes or geological reservoirs, was measured in several studies (Singer and Stumm, 1970;Reiterer et al, 1981;Bruno et al, 1992;Duckworth and Martin, 2004;Tang and Martin, 2011). Siderite dissolves in water according to the reaction FeCO3(s) + 2H + → H2O + CO2(g) + Fe 2+ , with an equilibrium constant K0 equal to 10 -7.59 at 25°C, under neutral pH conditions and in a 1M NaClO4 solution (Bruno et al, 1992).…”

Section: Dissolution Of Sideritementioning

confidence: 99%

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Siderite dissolution coupled to iron oxyhydroxide precipitation in the presence of arsenic revealed by nanoscale imaging

et al. 2017

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Siderite, the iron carbonate mineral, occurs in several geological environments and contributes to both the global iron and CO2 cycles. Under crustal conditions, this mineral may dissolve, releasing iron that becomes oxidized and then precipitates in the form of iron oxides and oxyhydroxides that have a high affinity for pollutants, such as arsenic. The process of siderite dissolution, dissolved iron oxidation, and oxyhydroxide precipitation is coupled in time and space. Here, we study the entire process using time-lapse in-situ atomic force microscopy. Natural siderite crystals were dissolved at room temperature in acidic aqueous solutions in the presence or absence of arsenic. The dissolution process, whose rate could be measured at a nanometer scale, occurred by the nucleation and growth of etch pits, the retreat of step edges, and the deepening of cleavage steps. Precipitation of iron oxyhydroxide phases coupled to siderite dissolution was imaged in-situ. Nucleated particles have an initial height of 1-2 nm after Highlights-Siderite dissolution is coupled to iron oxyhydroxides precipitation in acidic conditions-Siderite dissolution occurs by etch pits propagation, step retreat, and cleavage plane widening-Arsenic is adsorbed by the precipitated iron oxyhydroxides

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Section: Using Siderite To Remediate Polluted Waterssupporting

confidence: 80%

Section: Dissolution Of Sideritesupporting

confidence: 77%

Section: Using Siderite To Remediate Polluted Watersmentioning

confidence: 85%

Section: Dissolution Of Sideritementioning

confidence: 99%

See 2 more Smart Citations

Siderite dissolution coupled to iron oxyhydroxide precipitation in the presence of arsenic revealed by nanoscale imaging

et al. 2017

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“…Over the past three decades, several publications were reported to employ AFM method in siderite formation research. Tang et al [29] examined the dissolution behavior of siderite in the presence of oxidant chromate with the aid of AFM. While R.M.…”

Section: Introductionmentioning

confidence: 99%

Density Functional Theory and Atomic Force Microscopy Study of Oleate Functioned on Siderite Surface

Zhang

Yuan

et al. 2018

Minerals

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Abstract:Efficiently discovering the interaction of the collector oleate and siderite is of great significance for understanding the inherent function of siderite weakening hematite reverse flotation. For this purpose, investigation of the adsorption behavior of oleate on siderite surface was performed by density functional theory (DFT) calculations associating with atomic force microscopy (AFM) imaging. The siderite crystal geometry was computationally optimized via convergence tests. Calculated results of the interaction energy and the Mulliken population verified that the collector oleate adsorbed on siderite surface and the covalent bond was established as a result of electrons transferring from O1 atoms (in oleate molecule) to Fe1 atoms (in siderite lattice). Therefore, valence-electrons' configurations of Fe1 and O1 changed into 3d 6.51 4s 0.37 and 2s 1.83 2p 4.73 from 3d 6.21 4s 0.31 and 2s 1.83 p 4.88 correspondingly. Siderite surfaces with or without oleate functioned were examined with the aid of AFM imaging in PeakForce Tapping mode, and the functioned siderite surface was found to be covered by vesicular membrane matters with the average roughness of 16.4 t nm assuring the oleate adsorption. These results contributed to comprehending the interaction of oleate and siderite.

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Hydrothermal synthesis of a magnetic adsorbent from wasted iron mud for effective removal of heavy metals from smelting wastewater

Zhu

Dong

et al. 2018

Environ Sci Pollut Res

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A magnetic adsorbent (MA) was synthesized from wasted iron mud of a groundwater treatment plant using a novel one-step hydrothermal method. The results showed that Fe content of MA was 41.8 wt%, 2.5 times higher than that of iron mud, which was caused by hydrothermal dissolution of non-ferrous impurities under alkaline condition, such as quartz and albite, regardless of addition of ascorbic acid or not. Ferrihydrite was 92.7% in dry iron mud before adding ascorbic acid and gradually decreased to 58.1% by increasing the molar ratio of ascorbic acid to Fe following hydrothermal treatment. The strongest saturation magnetization of 16.29 emu/g was observed in the prepared MA-4 when the ascorbic acid to Fe molar ratio was 1. The highest surface site concentration of 1.31 mmol/g was observed in MA-2 when the ratio was 0.02. The mechanism of hydrothermal conversion of wasted iron mud to MA was reductive dissolution of ferrihydrite to form siderite, which was then reoxidized to maghemite. When 12.5 g/L of MA-2 was applied to treat smelting wastewater, over 99% removal of Cu, Zn, Pb, and Cd was achieved. The major mechanisms of Cu and Zn adsorption by the adsorbent were cationic exchange.

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Siderite dissolution in the presence of chromate

Cited by 20 publications

References 51 publications

Siderite dissolution coupled to iron oxyhydroxide precipitation in the presence of arsenic revealed by nanoscale imaging

Siderite dissolution coupled to iron oxyhydroxide precipitation in the presence of arsenic revealed by nanoscale imaging

Density Functional Theory and Atomic Force Microscopy Study of Oleate Functioned on Siderite Surface

Hydrothermal synthesis of a magnetic adsorbent from wasted iron mud for effective removal of heavy metals from smelting wastewater

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