goethite, a widespread iron oxide mineral [ α -FeO (OH)] and the most common ingredient of iron rust. It was named in 1806 for J.W. von Goethe, a German poet and philosopher with a keen interest in minerals. The name was originally applied to lepidocrocite [ γ -FeO (OH)], a less common mineral with the same chemical composition as goethite ...
However, goethite landfilling can pose several economic and environmental disadvantages, due to the high cost of its impounding and the risk of heavy metal leaching. Although goethite contains a substantial amount of valuable metals, the currently available technology does not permit an economically convenient extraction of these metals.
Low-temperature roasting can improve the conversion of Al-goethite in gibbsitic bauxite to porous Al-hematite, and favor increasing the alumina extraction during Bayer digestion and enrichment of iron minerals in red mud. The conversion of Al-substituted goethite (Al-goethite) to hematite in gibbsitic bauxite is conducive to alumina extraction during the …
Abstract. Diphenylarsinic acid (DPAA) is an organoarsenic compound derived from abandoned chemical weapons. DPAA sorption by iron (hydr)oxides is of considerable importance but remains largely unexplored. The current study aimed at investigating the sorption mechanisms of DPAA on ferrihydrite, goethite and hematite …
The extraction of goethite (soft/hydrated and hard/compact) and calcite did not cause breakage or fractures on the experimental tools, which did not change their morphology. ... MNF, Ortiz LP, Fernández FSR (2007) La más antigua minería metálica en tierras de León. In El hallazgo leonés de Valdevimbre y los depósitos del Bronce Final ...
From goethite to hematite: thermoanalytical aspects. The DTA curves in Fig. 1 display, as more intense endothermic peaks, those pertaining to the phase transition from goethite to hematite, occurring during the first heating run of the two goethite materials (SA and GS). This irreversible transformation occurs, as expected [3, 6, 7, …
Abstract. Jamaican bauxite deposits can broadly be classified into two types, catchment and hillside, depending on their form and topographic setting. The major iron phase in catchment deposits is hematite, while in hillside deposits this is aluminous goethite. The difference in topographical setting between the catchment and hillside deposits ...
The bio-extraction of phosphorus from goethite ore by naturally existed alkaline-tolerant microorganisms was investigated in current studies. In which, the microbial growth, medium pH, and phosphorus extraction were monitored. It was found that alkali addition did not possess any positive effect on either microbial growth or phosphorus …
Sequential extraction procedure applied to sorbed DPAA on ferrihydrite (A), goethite (B) and hematite (C) (initial DPAA concentrations: 4–100 mg L −1). All results are expressed as means of duplicate samples and presented as percentage (%) of the total extracted DPAA concentration present in the spiked iron (hydr)oxides.
The microbiologic reduction of a 0.2 to 2.0 μm size fraction of an Atlantic coastal plain sediment (Eatontown) was investigated using a dissimilatory Fe (III)-reducing bacterium ( Shewanella putrefaciens, strain CN32) to evaluate mineralogic controls on the rate and extent of Fe (III) reduction and the resulting distribution of biogenic Fe (II).
Sorption mechanisms of diphenylarsinic acid on ferrihydrite, goethite and hematite using sequential extraction, FTIR measurement and XAFS spectroscopy Zhu, Meng Hu, Xuefeng
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 …
Beneficiation Strategies for Removal of Silica and Alumina from Low-Grade Hematite-Goethite Iron Ores. V. Nunna., S. P. Suthers., M. I. Pownceby. & G. J. …
Fig. 2 illustrates Pb extraction at equilibrium by chelating agents as a function of solution pH. At pH higher than 8, obvious decreases in Pb extraction efficiency were found for both EDDS and EDTA. Goethite possessed negative surface charge at pH higher than 7.8 and chelating agents also had greater negative charge at higher pH …
Goethite (α-FeOOH) is a common oxy-hydroxide in natural environment and is formed as a weathering product of iron-bearing minerals. This mineral is the most …
Goethite. Locality: Mesabi district, Minnesota, USA. Name Origin: Named after the German poet, J. W. Goethe (1749-1832).Goethite (FeO (OH)), named after the German polymath and poet Johann Wolfgang von Goethe (1749–1832), an iron bearing hydroxide mineral of the diaspore group, is found in soil and other low-temperature …
Diphenylarsinic acid (DPAA) is an organoarsenic compound derived from abandoned chemical weapons. DPAA sorption by iron (hydr)oxides is of considerable importance but remains largely unexplored. The current study aimed at investigating the sorption mechanisms of DPAA on ferrihydrite, goethite and hematite using both …
Materials and experimental infrared spectroscopy. The goethite sample analyzed here is the non-aluminous synthetic sample 3/0 from the series studied by Murad and Schwertmann (), prepared according to the synthesis procedure of Goodman and from the Fe(II) path at T = 25 °C.Infrared experiments were performed using a Fourier …
Goethite is a common iron oxide mineral that has a chemical formula of FeO(OH). It is often referred to as "limonite" although that term is used more broadly to describe a mixture of various iron oxides and hydroxides.
In contrast, 0.2 M ammonium oxalate at pH 3.0 is able to dissolve all the iron compounds if the extraction time is sufficient. Nevertheless, the amount of EDTA-extractable iron is equal to the amount of iron extracted after 4–5 hours with ammonium oxalateat pH 3.0.
Goethite is one of the important ferruginous mineral in lateritic rock, lateritic iron ore and important part of the iron ore slimes. It occurs as vitreous …
The dithionite extraction robustly removes the targeted mineralogy as magnetic data show it to solubilize nearly all of the goethite. However, magnetic quantification of magnetite was orders of magnitude less than the iron measured in the oxalate extraction; X-ray diffraction data suggest that dissolution of iron-bearing clays, …
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 …
Goethite is the source for the pigment known as yellow ochre; it is also the primary mineral in some important iron ores, such as those in the …
Iron ore for steelmaking. Goethite is the main mineral in iron ore, which is used to make steel. Australia is the world's largest iron ore exporter and demand is expected to grow. Our red center ...
Goethite is the most common of the iron oxyhydroxides and is antiferromagnetic with a disordering (Néel) temperature of about 120°C (Hedley, 1971 ). Goethite has weak saturation magnetization and very high coercivity ( Hedley, 1971; Rochette and Fillion, 1989 ). It dehydrates to hematite at about 300°C.
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. …
The Yuanjiang nickel laterite ore containing mainly maghemite, goethite and lizardite was leached by sulphuric acid at atmospheric pressure and the residues were characterized using X-ray diffraction and scanning electron microscopy/X-ray energy dispersive spectroscopy. The relationship was discussed between the extraction of …
Apostolidis and Distin (1978) found that the extraction of iron from the pregnant leaching solution of the pre-reduced laterite nickel had partial selectivity over magnesium from laterites contain- ore. ing serpentine by reduction roasting followed by sulphuric acid Removal of iron via goethite precipitation process can be effected leaching.
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.
Goethite in the Orissa banded iron formation has six morphotypes: botryoidal, nodular, spheroidal, platy, stalactitic and fl aky. Excepting the fl aky and. Fig. 4 Optical micrograph of goethite (Go) fi lling a cavity. The higher refl ective patches of hematite (Ht) present over goethite are formed due to dehydration.
Goethite precipitates on the surface of the external magnetic seeds to form core-shell structured particles, which are efficiently separated by magnetic separation, and at the same time solve the two …
ABSTRACT. As higher-grade ores become depleted, there will be a greater focus on developing suitable beneficiation strategies to treat low-grade hematite-goethite ores containing higher levels of impurities such as silica and alumina.
Goethite is the most abundant thermodynamically stable iron oxide phase that is widely distributed in rocks, and soils (Llavona et al., 2013). It is a yellow antiferromagnetic iron oxide phase ...
Dissolved Ni readily sorbs onto pure goethite and is mostly recovered through an acid extraction but in the presence of Fe(II)aq, a significant fraction of Ni incorporates into the mineral and is ...
The enthalpy of formation of goethite can vary by 15–20 kJ/mol as a function of surface area. The plot of calorimetric data vs. surface area gives a surface enthalpy of 0.60±0.10 J/m 2 and enthalpy of formation of goethite (with nominal composition FeOOH and surface area = 0) of −561.5±1.5 kJ/mol.