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Dithionite as a Dissolving Reagent for Goethite in the Presence of Edta and Citrate. Application to Soil Analysis - Volume 40 Issue 5 ... Departamento de Química e Ingeniería Química, Universidad Nacional del Sur, Avenida Alem 1253, (8000) Bahía Blanca, Argentina ... 1991 Extraction of iron oxides from sediments using reductive dissolution ...
Activated plywood sawdust impregnated Fe/Al oxyhydroxide as a new composite. • Acacia auriculiformis leaf extract was used as a new green capping agent.. Outstanding Cr(VI) uptake capacity 193.913 mg.g −1 was found.. Fixed bed column adsorption capacity recorded 218.500 mg.g −1 at 7 mg. L –1, and pH 7.. Exhausted material was pyrolyzed …
The objectives of this study were (1) to evaluate the metal extraction from Pb-goethite by EDDS and EDTA at different pH and reaction times in batch study; (2) to provide insight into the behavior of EDDS and EDTA at the solid–liquid interface during Pb extraction using ATR/FT-IR; and (3) to quantify the extent of PbEDDS and PbEDTA adsorption ...
The development of a sequential extraction procedure for iron in modern and ancient sediments is presented. The scheme recognizes seven operationally derived iron pools: (1) carbonate associated Fe (Fe carb), including siderite and ankerite; (2) easily reducible oxides (Fe ox1), including ferrihydrite and lepidocrocite; (3) reducible oxides (Fe ox2), …
The current study aimed at investigating the sorption mechanisms of DPAA on ferrihydrite, goethite and hematite using both macroscopic sorption kinetics and sequential extraction procedure (SEP) as well as microscopic Fourier transformed infrared (FTIR) and extended X-ray absorption fine structure (EXAFS) spectroscopic techniques.
Dithionite-citrate-bicarbonate (DCB) treatment is a classical method for removing iron oxides from soil. The DCB-induced dissolution effects on iron oxides are controversial. In this paper ...
a 24-h extraction with 1 N HCl at room tem- perature and extraction with dithionite leach comparable amounts of Fe, even though lep- idocrocite, goethite, and hematite are dis- solved with dithionite and are not attacked by 1 N HCl (Table 1). Acknowledgments
The aim of this study was to precipitate goethite from high-iron(II)-bearing atmospheric and heap leach solutions of lateritic nickel ore generated either by reductive leaching of the …
Request PDF | Selective extraction of amorphous iron oxide by EDTA from a mixture of amorphous iron oxide, goethite, and hematite | Iron (III) was extracted by EDTA and ammonium oxalate from a ...
Goethite (FeO2H) can also occur in iron ore formations due to the hydration of other ironbearing species. In flotation and pelletization, goethite behaves well if accounted for as it has good ...
Sometimes, goethite contains a high content of phosphorus (P) and the existing phosphorus removal techniques is to thermally roasted the ore with or without alkaline additives followed by chemical ...
Therefore, it is concluded that it may be possible by means of EDTA to carry out a selective extraction of X-ray amorphous iron oxides mixed with goethite and hematite. REFERENCES Aguilera, N. H., and Jackson, M. L. 1953 .
Request PDF | On Mar 1, 2019, Meng Zhu and others published Sorption mechanisms of diphenylarsinic acid on ferrihydrite, goethite and hematite using sequential extraction, FTIR measurement and ...
Goethite has weak saturation magnetization and very high coercivity (Hedley, 1971; Rochette and Fillion, 1989). It dehydrates to hematite at about 300°C. Goethite is an important product in low-temperature oxidation, particularly of iron sulfides, and is a constituent of manganese nodules and of the Pacific red clay facies, where it may ...
Iron ore with significant goethite content can be processed to extract iron and used in the production of steel and other iron-based products. Catalysis: Goethite nanoparticles have shown promise as catalysts in various chemical reactions. Their high surface area and reactivity make them useful for catalyzing oxidation and reduction reactions ...
The conversion of Al-substituted goethite (Al-goethite) to hematite in gibbsitic bauxite is conducive to alumina extraction during the Bayer process and the enrichment of iron …
Goethite coated with aluminium on its surfaces is known to reduce adsorption ... González F. Mercury extraction from cinnabar ores using hydrobromic acid: previous studies. …
The conversion of Al-substituted goethite (Al-goethite) to hematite in gibbsitic bauxite is conducive to alumina extraction during the Bayer process and the enrichment of iron minerals in red mud. In this work, mineralogical characteristics of gibbsitic bauxite were identified by AMICS analysis, and …
Goethite exhibits grey color and forms as an alteration product after magnetite and pyrite (Fig. 12 E). Goethite showing typically under oxidizing condition as a weathering product of iron bearing minerals, such as: magnetite, pyrite. Goethite most typical habits are as porous bands with radiating fibrous or as porous pseudomorphs after pyrite.
In this study, batch experiments were performed to quantify the Pb extraction from goethite by EDTA and EDDS, respectively, and attenuated total reflectance-Fourier transform infrared (ATR/FT-IR ...
Scandium (Sc) is the lightest of REE. It has atomic number 21, thus being the neighbor of calcium (Ca). Unlike calcium, which is the fifth most abundant element in the Earth's crust, Scandium is scarce, but still more abundant than lead, tin, silver etc. Scandium has the electron configuration [Ar]3s 2 3d 1.This immediately indicates that the sole oxidation …
The study of the extraction of Re% As(Ill) 100" 80" 60" 40 20 G---~ D Goethlto (oIL)r 0 I 3 5 9 11 13 pH Fig. 4. Sorption of As(III) on goethite (contact time 30 min), at two different sorbent concentrations. pollutants using novel inorganic ion exchangers (of synthetic or natural origin), is considered to be an innovative research field.
Thermodynamic simulations using the software HSC 8 (HSC Chemistry, 2015) is shown in Fig. 2, where lanthanum sulfate represents the REE family.The initial molar composition of the system was set at 12.5% La 2 O 3, 12.5% Fe 2 O 3 and 75% H 2 SO 4.The simulation confirms that the selective pyrolysis of iron over the rare earths can be achieved in a …
The effect of mineralogy and texture on the beneficiation of goethitic ores from two different origins is highlighted. Sample A having 54.47% Fe with 8.57% loss of ignition (LOI) …
Table 1 Relative abundances of Sc measured by ICP-AES and EDX/TEM.. Figure 1 X-ray diffractograms for goethite, ScOOH and Sc-doped goethite samples.. Figure 2 Top: Changes in cell parameters and in cell volume as a function of rate of substitution of Fe by Sc (numerical data for cell parameters and errors can be found in SI). Dashed lines …
1 Introduction. The dissolution of (nano)materials is of great interest to investigate to a wide range of research fields, including climate and atmospheric CO 2 storage associated with rock erosion, [1-3] agricultural nutrient release strategies, [] bioweathering in ecology, [] energy storage in batteries, [] and corrosion science [] involving biomaterials, [] but also …
Table 1 Relative abundances of Sc measured by ICP-AES and EDX/TEM.. Figure 1 X-ray diffractograms for goethite, ScOOH and Sc-doped goethite samples.. Figure 2 Top: …
Extraction of arsenic (As) from adsorbed (ad) and coprecipitated (cpt) As-Fe(OH) 3, As-Fe 3 O 4 using phosphate buffer, sodium hydroxide (NaOH), hydrochloric acid (HCl), and oxalate buffer was studied. In addition, the effects of the solution concentrations, sample drying, aging time, and goethite and fresh As-Fe(OH) 3 (cpt) mixture on the extraction …
Preparation and evaluation of functionalized goethite nanorods coated by molecularly imprinted polymer for selective extraction of bisphenol A in aqueous medium. ... Goethite is one of the most common and thermodynamically stable iron oxide in sediments and natural systems. This mineral due to their rode-like morphology provide high surface-to ...
Abstract. The sorption kinetics of antimony(V) on synthetic goethite is very fast compared to the sorption of other metals on goethite (e.g. arsenic and selenium) and depends on temperature, with an activation energy of 49±9 kJ · mol −1 in the temperature range 15–35°C. Sorption isotherms have been developed at different temperatures and ionic …
The acetate extraction dissolved most of this high-coercivity phase as well as some pyrrhotite and goethite. The dithionite extraction effectively solubilized the remainder of these two phases although a small amount of pyrrhotite remained and was slightly dissolved during the oxalate extraction. See Figure 2 caption for abbreviations.
Goethite is a hydrous iron oxide mineral and presents as an acicular, fine- to medium-grained, anhedral to subhedral crystals with irregular outlines. It exhibits grey color with …
Cela nous a permis de proposer trois hypothèses probables de transformation topotactique : GR→l e ́ pidocrocite; WR→goethite et l e ́ pidocrocite→goethite Ces hypothèses de transformation sont en bon accord avec les résultats expérimentaux concernant la préparation des oxy-hydroxydes de fer.
The objectives of this study were (1) to evaluate the metal extraction from Pb-goethite by EDDS and EDTA at different pH and reaction times in batch study; (2) to provide insight into the behavior of EDDS and EDTA at the solid–liquid interface during Pb extraction using ATR/FT-IR; and (3) to quantify the extent of PbEDDS and PbEDTA adsorption ...
The aim of this study was to precipitate goethite from high-iron(II)-bearing atmospheric and heap leach solutions of lateritic nickel ore generated either by reductive leaching of the ore or by reducing Fe(III) of the leach solution to Fe(II) using a suitable reducing agent and to understand the Ni and Co losses during the iron precipitation. Removal of Fe was …