Spectroscopic and thermoanalytical characterization of standard substances for the identification of reaction products on iron electrodes

Nauer, Gerhard; Strecha, Peter; Brinda-Konopik, N.; Liptay, G.

doi:10.1007/bf01913309

Cited by 92 publications

(54 citation statements)

References 18 publications

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“…Raman spectra on various goethite-rich areas are shown in Figures 2a to 2d. The spectra show broad bands at 298 and 395 cm -1 suggesting poorly or microcrystalline goethite, and sharp peaks, indicative of more crystalline goethite, at 240,298,395,478,549,687,1001,1116 and 1302 cm -1 (Nauer et al 1985, Dünnwald & Otto 1989. The width and the slight shift of some of the Raman peaks may also be attributed to sulfur.…”

Section: Morphological and Mineralogical Characteristics Of The Two Smentioning

confidence: 93%

The Weathering of a Sulfide Orebody: Speciation and Fate of Some Potential Contaminants

Courtin-Nomade¹,

Grosbois²,

Marcus³

et al. 2009

The Canadian Mineralogist

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Various potentially toxic trace elements such as As, Cu, Pb and Zn have been remobilized by the weathering of a sulfide orebody that was only partially mined at Leona Heights, California. As a result, this body has both natural and anthropogenically modified weathering profiles only 500 m apart. The orebody is located in a heavily urbanized area in suburban Oakland, and directly affects water quality in at least one stream by producing acidic conditions and relatively high concentrations of dissolved elements (e.g., ~500 mg/L Cu, ~3700 mg/L Zn). Micrometric-scale mineralogical investigations were performed on the authigenic metal-bearing phases (less than 10 mm in size) using electron-probe micro-analysis (EPMA), micro-Raman, micro X-ray absorption spectroscopy (mXAS), scanning X-ray diffraction (mSXRD) and scanning X-ray fluorescence (mSXRF) mapping techniques. Those measurements were coupled with classical mineralogical laboratory techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Authigenic metal-bearing phases identified are mainly sulfates (jarosite, epsomite, schwertmannite), Fe (oxy-)hydroxides (goethite, hematite and poorly crystalline Fe products) and poorly crystalline Mn (hydr-)oxides. Sulfates and Fe (oxy-)hydroxides are the two main secondary products at both sites, whereas Mn (hydr-) oxides were only observed in the samples from the non-mining site. In these samples, the various trace elements show different affinities for Fe or Mn compounds. Lead is preferentially associated with Mn (hydr-)oxides and As with Fe (oxy-)hydroxides or sulfates. Copper association with Mn and Fe phases is questionable, and the results obtained rather indicate that Cu is present as individual Cu-rich grains (Cu hydroxides). Some ochreous precipitates were found at both sites and correspond to a mixture of schwertmannite, goethite and jarosite containing some potentially toxic trace elements such as Cu, Pb and Zn. According to the trace element distribution and relative abundance of the unweathered sulfides, this orebody still represents a significant reservoir of potential contaminants for the watershed, especially in the non-mining site, as a much greater proportion of sulfides is left to react and because of the lower porosity in this site.

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Section: Morphological and Mineralogical Characteristics Of The Two Smentioning

confidence: 93%

The Weathering of a Sulfide Orebody: Speciation and Fate of Some Potential Contaminants

Courtin-Nomade¹,

Grosbois²,

Marcus³

et al. 2009

The Canadian Mineralogist

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“…This spectrum is very similar to the maghemite spectra shown by De Faria et al 21 and Boucherit et al 17 The broad band at around 700 cm 1 can also be observed on other iron components. In this region, it can be assigned to υ-FeOOH 19,21,27,28 or to ferrihydrite. 11,29 These phases were synthesised following the procedure of Schwertmann and Cornell 26 and analysed by Raman spectroscopy (Fig.…”

Section: Identification Of Iron Corrosion Products By Raman Micro-spementioning

confidence: 99%

“…Keiser et al 27 present a spectrum with the main peak at 678 cm 1 , Nauer et al 28 at 663 cm 1 and Boucherit et al 19 at 655 cm 1 . Our spectrum is very similar to the one given by De Faria et al, 21 which gives two peaks, the one at 680 cm 1 being the most intense and that at 400 cm 1 being the second.…”

Section: Identification Of Iron Corrosion Products By Raman Micro-spementioning

confidence: 99%

Raman imaging of ancient rust scales on archaeological iron artefacts for long‐term atmospheric corrosion mechanisms study

Neff¹,

Bellot‐Gurlet²,

Dillmann³

et al. 2006

J Raman Spectroscopy

212

127

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Iron archaeological artefacts were studied to understand long-term corrosion by the atmosphere. Indeed, these samples collected on the construction elements of ancient monuments present ancient rust layers formed during their exposure over centuries to the indoor atmosphere. Thanks to Raman spectroscopy and the acquisition of hyperspectral images of the corrosion scales, several zones of the samples observed on cross sections could be characterised. It has been shown on six dated samples that the main phase is goethite (a-FeOOH). Lepidocrocite and akaganeite (g-FeOOH and b-FeOOH) occur locally in the corroded products, often correlated with cracks. A less crystallised phase, a hydrated oxy-hydroxide, has been identified abundantly in more or less extended zones inside the layer. This phase could play an important role in atmospheric corrosion mechanisms.

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“…The positions of the important absorption bands for the various iron containing phases are summarized in Table 1 [9]- [15]. This table is modeled after the work by Nauer et al [9] that tabulated the peak positions of goethite (δ-FeOOH), akaganéite (δ-FeOOH), lepidocrocite (δ-FeOOH), feroxyhite (δ-FeOOH), and bernalite (Fe(OH) 3 ). These authors also used the following assignments for IR absorbances: 1) 3600 to ca.…”

Section: Product Characterizationmentioning

confidence: 99%

Thermodynamic Study for Arsenic Removal from Freshwater by Using Electrocoagulation Process

Parga¹,

Valenzuela²,

Munive³

et al. 2014

ACES

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Insert Industrial treatment of mineral-processing and non-ferrous metal-smelting acid wastewater effluents is becoming an enormous worldwide problem. In Mexico, heavy metalscontaminated natural waters, including freshwater, surface water and ground water, are a significant problem as some of these compounds are known as toxic, mutagenic, and carcinogenic. A very promising electrochemical treatment technique that does not require chemical additions to remove arsenic is electrocoagulation (EC) with air injection. The proposed electrochemical process is efficient because used low cost iron electrodes and promising in industrial application. Theoretical the purpose of this research was to investigate the thermodynamic of arsenic adsorption on iron species using the Langmuir's Isotherm. Also, thermodynamic parameters such as ∆H  , ∆S  and ∆G  were calculated and the adsorption process was found to be exothermic and spontaneous. X-ray Diffraction and Scanning Electron Microscopy, were used to characterize the solid products formed during EC. The results of this study suggest that magnetite particles and amorphous iron oxyhydroxides are present in the examined EC products and this study indicate that arsenic can be successfully adsorbed on iron species by electrocoagulation process. Field pilot-scale study demonstrated the removal of As(III)/As(V) with an efficiency of more than 99% from both wastewater and wells.

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Spectroscopic and thermoanalytical characterization of standard substances for the identification of reaction products on iron electrodes

Cited by 92 publications

References 18 publications

The Weathering of a Sulfide Orebody: Speciation and Fate of Some Potential Contaminants

The Weathering of a Sulfide Orebody: Speciation and Fate of Some Potential Contaminants

Raman imaging of ancient rust scales on archaeological iron artefacts for long‐term atmospheric corrosion mechanisms study

Thermodynamic Study for Arsenic Removal from Freshwater by Using Electrocoagulation Process

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