abstract = "Enriched Fe isotope tracer studies demonstrate that aqueous Fe(II) undergoes electron transfer and atom exchange with goethite. Such processes influence contaminant fate and trace-element mobility, and result in stable Fe isotope fractionation in both biological and abiological processes.
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Different dissolution mechanisms cause diverseIron isotope fractionation effects and likely influence the iron isotope signature of natural soil and weathering environments. Iron isotope fractionation during dissolution of goethite (alpha-FeOOH) was studied in laboratory batch experiments. Proton-promoted (HCl), ligand-controlled …
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Keywords: Abrasion Index, Ferrites, Goethite Ich Iron ore, Reducibility Index, Reduction Degradation Index SFCA, Sinter, Tumbler Index, etc. INTRODUCTION During mining of iron ores, lots of fines (<10 mm) are generated which are not suitable for direct use in the blast furnace for iron making. Agglomeration technique applied for the coarser ...
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The magnetic behaviour during stepwise demagnetization of a set of artificial samples, containing well-defined natural goethite from five localities (chemical …
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The characteristics of microbial goethite reduction in "strain S12-redox mediator" pre-incubation reaction systems. Both the concentrations of dissolved reductively produced ferrous iron(Fe(II ...
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2.3 Paragenesis. Typical weathering product, particularly in secondary supergene concentrations of sulphides (oxidation zone, gossan), laterites and limonites but also as a primary mineral in hydrothermal and sedimentary formations. Goethite is a mineral that continues to form on the earth's surface on a daily basis, due to the poor …
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H 2 O 2-modified iron shavings (HMI) with surface γ-FeOOH film were effective as a catalyst in catalytic ozonation, but the iron leaching and loss of surface component limited its application.In this study, Cr-modified iron shavings (CrMI) was developed by introducing Cr 3+ to promote Cr-substituted goethite (α-Fe(Cr 3+)OOH) …
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The iron oxides hematite, magnetite, and goethite were studied with density functional theory to establish a consistent set of structures for both the bulk mineral and …
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In this study, we investigated local structures of Sb species in synthetic SbV-coprecipitated and -adsorbed ferrihydrite and goethite, which are common iron(III) oxyhydroxides in environment, at various Sb/Fe molar ratios by extended X-ray absorption fine structure (EXAFS) analyses. The EXAFS analyses showed that SbV is adsorbed on ferrihydrite …
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Study of microwave-assisted magnetizing roasting and mineral transformation of low grade goethite iron ores), and; Mineralogical characterisation of goethite (Pownceby, M I, MacRae, C M and Torpy, A, 2017. A comparison of X-ray and electron-based analysis techniques for characterising the mineralogy and associated alumina deportment in iron …
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Additionally, two major peaks at 2θ = 44.8°, 65.2° were identified as iron and appeared when goethite was reduced over 450 °C. As shown in Fig. 1, at 250 °C and 350 °C, the product of the reduced goethite was only magnetite. However, iron was found from XRD of goethite reduced at 450 °C.
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Pentachloronitrobenzene is a fungicide that is degraded in anoxic soils and sediments through unknown processes that are often thought to be biologically mediated. The present research describes the kinetics for the abiotic reduction of this compound in aqueous Fe(II)/goethite systems at near-neutra …
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Iron (Fe) Compounds The XPS Spectra section provides raw and processed survey spectra, chemical state spectra, BE values, FWHM values, and overlays of key spectra. Atom% values from surveys are based on sample, as received, and Scofield cross-sections. Atom% values are corrected for IMFP and PE.
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irridescent goethite (limonite) Mt Morgan mine Qld Australia. Properties: Variable lustre; Crystals often metallic, other forms submetallic to earthy ... Goethite is the main constituent of limonite which is formed by the prolonged weathering of iron-bearing rocks and ores. 4.6.2 irridescent goethite (limonite) Mt Morgan mine Qld Australia . 4. ...
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We measured the Fe isotope fractionation during the reactions of Fe(II) with goethite in the presence and absence of a strong Fe(III) chelator (desferrioxamine mesylate, DFAM).All experiments were completed in an O 2-free glove box.The concentrations of aqueous Fe(II) ([Fe(II) aq]) decreased below the initial total dissolved …
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As dust-laden iron travels farther from the Sahara, atmospheric reactions make it increasingly accessible to support life. Iron is an essential micronutrient for life, …
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About Goethite. Goethite is a mineral associated with the Root chakra, located at the base of the spine. It is known for its grounding and stabilizing properties. ... It is commonly utilized as an iron ore and …
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1.. IntroductionStainless steel finishing operations involve several cleaning processes, which eliminate dust, scale and metallic oxides [1].Mill scale is a steel making by-product from steel hot rolling processes and is basically composed of iron oxides and metallic iron with variable oil and grease contents [2], [3].Its specific production is about …
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Mineral Associations: Goethite is often found in association with other iron minerals, such as hematite, magnetite, and siderite. It can also occur alongside other minerals like quartz, clay minerals, and …
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Goethite (a-FeOOH) This iron oxide polymorph was prepared using the method of Thiebeau et al. [23] with some modifications. Ferric precursor (20 g) was dissolved in 500 ml of distilled water. To the filtered solution 100 ml of 1 M NaHCO3 solution was added which brought the pH to values between 5 and 7. The solution was held at 100 C for 1 h ...
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Both natural hematite and goethite from Cerro del Hierro (Spain) were used in the experiments, crushed and sieved to a particle size of 0.25 mm. X-ray diffraction analysis (Fig. 1) revealed the presence of the pure iron oxi-hydroxides and traces of quartz.The specific surface area was determined by the BET methodology, the values …
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Phosphate adsorption on the surfaces of the iron oxyhydroxide polymorphs goethite, akaganeite, and lepidocrocite were studied by using 31P static spin-echo mapping NMR experiments to determine how ...
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A list of the iron ore minerals commonly observed in Australian iron ore deposits is provided in Table 1.In the Pilbara region of northwest Western Australia, the high-grade (i.e., >62 wt-% Fe) bedded iron deposits (BID) are characterised by martite-microplaty hematite (M-mpl H) and/or martite-goethite (M-G) ore types (Morris, 1980, …
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A shear-enhanced method based on strong homogenization was proposed and applied in the goethite process for iron removal from the zinc process solution to overcome the low reaction efficiency and the difficulty in residue filtration. A 3D shear-enhanced rector model was designed, and the process was simulated to reveal the …
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FT-IR spectra of the synthesized goethite mineral (Fig. 2) show very broad IR band at 3174.1 cm −1, which can be attributed to the stretching vibration of surface H 2 O molecules.The characteristic sharp bands at 798.0 cm −1 and 892.4 cm −1 can be assigned to the Fe–O–OH bending vibration in α-FeOOH. The 656.7 cm −1 band is …
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Iron is the fourth most abundant element, which can form complexes with elements such as C, N, O, and S, making it an essential element for nearly all living organisms 1,2,3,4,5,6,7.The ...
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Dissolution of redox-active metal oxides plays a key role in a variety of phenomena, including (photo)electrocatalysis, degradation of battery materials, corrosion of metal oxides, and biogeochemical cycling of metals in natural environments. Despite its widespread significance, mechanisms of metal-oxide dissolution remain poorly …
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The results of this study demonstrate that goethite can also provide a readily available iron source or act as a substrate for iron reduction that leads to formation of …
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Goethite is an antiferromagnetic iron-oxy-hydroxide (α-FeOOH) that crystallizes in the orthorhombic system. Goethite crystals are made out of smaller …
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Goethite, which is a common iron mineral found in soil with high iron oxide concentration and extensive surface area, has demonstrated satisfactory results in immobilizing the anionic forms of As ...
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Humic acid (HA) is particularly important in iron-bearing mineral transformations and erosion at the water-mineral boundary zone of the Earth. In this …
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The importance of goethite to Australian iron ore production is steadily increasing as the proportion of goethite-rich, martite-goethite bedded and channel iron deposits increases at the expense of declining production from high-grade microplaty hematite deposits. For this reason, an improved understanding of goethite in iron deposits, its genesis, goethite …
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The interactively interfacial reactions between the iron-reducing bacterium (Shewanella decolorationis, S12) and iron oxide (α-FeOOH) were investigated to determine reductive dechlorination transformation of chlorinated organic compounds (chloroform and pentachlorophenol). The results showed that the interactive system of S12+ α-FeOOH …
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Perfectly crystallized Goethite pseudomorphs after Pyrite come from Pelican Point, Utah Co., Utah; and attractive botryoidal forms were found in the famous Copper Queen Mine, Bisbee, Cochise Co., Arizona. Large deposits of Goethite can be found in Michigan in the Menominee iron range, Iron Co.; and in the Marquette iron range, Marquette Co.
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