Effectiveness of iron reducing bacteria for the removal of iron …
Removal of silica from low grade bauxites (Groudeva et al., 1983;Zhan et al., 2013) Bacillus mucilaginosus Removal of silica from bauxite (Groudeva and, 1986;Karavaiko et al., 1989;Zhan et al ...
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Simultaneous Application of Oxalic Acid and Sodium …
Bauxite is widely used to produce alumina. There are many bauxite resources with high iron content. These resources could not be processed and utilized efficiently due to the high concentration of iron (Fe). The alkaline leaching process has been proposed to remove iron from these bauxite resources. Therefore, in this study, …
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Bauxite Beneficiation: Efficient Way to Remove Silica in Bauxite
The main objective of bauxite beneficiation is to lower the concentration of reactive silica, and also to increase the alumina content. In addition, bauxite beneficiation can also be used for iron extraction or iron removal. Why desiliconize bauxite? Silicon is a harmful substance in the alumina production process.
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Characterization Study of some Bauxite Deposits in …
Abstract Alumina is produced from bauxite, which contains a mixture of various oxides, such as alu-minum (Al), iron (Fe), silicon (Si), and titanium (Ti). Bauxite can also be considered a source of several other valuable metals, such as scandium (Sc), vana-dium (V), and gallium (Ga). The composition and mineralogy of alumina determine their ...
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Beneficiation Aspects to Improve the Quality of Bauxite
Also et al. reported that Indian bauxite ores can be utilised in refractory industries . The procedure of removing iron from bauxite containing 2.7% Fe 2 O 3 was disclosed by Sadler and Venkataraman. A product was produced from Alabama bauxite containing 1.5% Fe 2 O 3 using calcinations followed by magnetic separation .
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Explain what happens if bauxite containing iron and silica as
Concentration of bauxite is done by different methods as there are different types of bauxite. Consider the process for concentration of bauxite. Process 1 : Employed for red bauxite to remove main impurity iron oxide. Process 2 : Employed for white bauxite to remove main impurity silica.
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Iron Removal from Bauxite by Oxalic Acid and Further Al
In the first set of experiments (Stage I), in the leaching of the bauxite ore in the presence of oxalic acid (H 2 C 2 O 4) to remove iron from the ore, the effects of leaching …
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Beneficiation of bauxite ores
It is widely recognized that the bauxite ore should be beneficiated, preferably where it is mined, to remove silica, iron, and other impurities invariably meeting the bauxite refinery norms of 42%–45% Al 2 O 3. Various attempts have been made to characterize and beneficiate bauxite ores across the globe.
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REMOVAL OF IRON-BEARING MINERALS FROM …
silicates and iron-bearing minerals are depressed with sodium silicate and starch, respectively [5-7]. Marino et al. [6] tested the direct and reverse flotation routes in order to concentrate the bauxite from Paragominas-PA, Brazil, which contains 47.7% of Al 2 O 3 and 4.0% of reactive silica, besides kaolinite and iron-bearing minerals.
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Biomineralization and Biobeneficiation of Bauxite
Bauxite is the most important raw material for production of aluminium metal and in the manufacture of abrasives, ceramics and refractories. Depending on the end use of the mined bauxite ores, appropriate prebeneficiation need to be adapted for removal of impurities such as calcium, iron oxides and silica.
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EP0950020A1
A process for removing silica from bauxite is disclosed. The method includes the step of mixing bauxite with a caustic liquor to form a mixture and to dissolve and stabilise at least a substantial part of the reactive silica from the bauxite. The caustic liquor is selected to have a high caustic concentration and a high alumina content.
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Recovery of Scandium, Aluminum, Titanium, and Silicon …
Crystals 2022, 12, 1578 3 of 27 Figure 1. A conceptual flowsheet of bauxite residue treatment in the present and previous studies. In this work, we focus on the recovery of valuable elements such ...
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THE ALUMINIUM STORY BAUXITE TO ALUMINA: THE …
For a bauxite ore to be economically processed it typically contains 30-50% of extractable (termed available) alumina, up to 20% of iron oxides and 2-5% of silica in reactive clays (typically kaolinite). Silica can also be present as quartz which is essentially unreactive in the Bayer Process. Questions
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Re‐using bauxite residues: benefits beyond (critical raw) …
Bauxite residues from alumina production. Aluminium production consists of two key stages: The first is alumina refining (Bayer process), which involves the generation of alumina from bauxite ore; the second stage is aluminium smelting (Hall–Héroult), the process of transforming alumina into aluminium.67 Most of the world's alumina is …
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Beneficiation of bauxite ores
It is widely recognized that the bauxite ore should be beneficiated, preferably where it is mined, to remove silica, iron, and other impurities invariably meeting the …
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Bauxite Beneficiation: An Approach to Value …
Fig. 1 General industrial flowsheet for removal of silica from Bauxite Ta b le 2 Characteristics of Sierra Leone bauxite (dry sieving) Sample Fraction %Al 2 O 3 %SiO 2 %Fe 2 O 3 %LOI Fraction %
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Advances in Beneficiation of Low-Grade Bauxite
efficiently removes calcium from the low-grade bauxite. Similarly, iron-oxidizing and silicate bacteria remove iron and solubilise silica, respectively, from the low-grade bauxite. However, pilot scale operation of the bauxite bio-beneficiation process has not been reported. Research related to biotechnology should be undertaken in the
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Enhanced removal of iron minerals from high-iron bauxite …
In this work, an advanced technique consisting of static pre-roasting in air and fluidized suspension roasting by hydrogen, followed by magnetic separation, was …
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Selectively leaching the iron-removed bauxite residues …
the separation of REEs against silica in advance. The feasibility of selectively removing silica from the iron-removed bauxite residues with simultaneously enrichment of REEs was investigated using different acid leaching agents such …
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Pilot Tests with Tertiary Cyclone for Reactive Silica …
tests. Consequently, available alumina grade increased from 43.3 % to 48.1 % and reactive silica reduced from 6.0 % to 3.3 %. The classification process was selective, with 89.3 % metallurgical recovery of alumina and 45.9 % recovery of silica to product. Keywords: Bauxite beneficiation, Clay removal, Silica reduction, Hydrocyclones. 1 ...
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Process Simulation with Tertiary Cyclone for Kaolinite Removal …
The Amazonian bauxite is of the lateritic type and is mostly located in Paragominas, Juruti, Trombetas, and Almerim [1, 9]. Kaolinite is a clay mineral commonly found in Amazonian bauxite and Brazilian iron ores. Due to its particle size, kaolinite is usually removed from the process in desliming steps using hydrocyclones.
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Iron Removal from Bauxite by Oxalic Acid and Further Al …
At the first stage, bauxite ore was leached under atmospheric conditions with oxalic acid, iron was selectively extracted into the solution, and the refractory aluminum was enriched in the leaching residue.
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Drum leaching tests in iron removal from quartz using …
DOI: 10.1016/S0301-7516(98)00014-3 Corpus ID: 94834403; Drum leaching tests in iron removal from quartz using oxalic and sulphuric acids @article{Vegli1998DrumLT, title={Drum leaching tests in iron removal from quartz using oxalic and sulphuric acids}, author={Franc Vegli{`o} and Bruno Passariello and Mar{'i}a Gabriela Di Barbaro …
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Beneficiation of Bauxite Ore Characterized by Low …
Keywords - Alumina, Aluminum, Bauxite, Beneficiation, Silica. 1. Introduction Primarily, bauxite ore exists in the form of aluminum oxide hydrates alongside impurities such as iron oxide, titanium dioxide, and silicon dioxide. Geologically, two major types of bauxite are recognized: lateritic bauxite and karst bauxites.
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Alumina recovery from bauxite residue: A concise review
Aluminum demand has increased with modernization of our society. As the primary source of aluminum is bauxite ore, this has resulted in more accumulation of bauxite residue.A bauxite residue typically contains 15–25% of alumina depending on the origin of its ore and process conditions. Along with alumina, it also contains iron, …
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Leaching for iron removal from low-grade bauxite ore to …
search is to investigate the possibility of iron removal from low-grade bauxite ores to utilize them in refractory industries. For achieving this purpose, iron removal tests were …
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Leaching for iron removal from low-grade bauxite ore …
For achieving this purpose, iron removal tests were performed on bauxite samples with an alumina to silica modulus of 0.73. After determining the appropriate iron removal method among the magnetic ...
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The Sandy Desilication Product Process Concept | JOM
The principal components of bauxite ores are aluminum-, iron-, and silicon-bearing minerals. In the Bayer process for recovery of alumina from bauxite,1 aluminum is dissolved into hot alkaline solution whilst iron is relatively insoluble. "Reactive silica" in the form of silicate minerals, such as kaolinite, typically dissolves and reprecipitates as …
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Impurity Removal in the Bayer Process
Guinean bauxite is generally benign with respect to impurity input, although its relatively high goethite content coupled with the need to digest at high temperature to extract the …
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High Iron Diasporic Bauxite Processing Study
The removal of soluble silica minerals in the pre-desilication and digestion steps is critical in ... [14] that most of the silica in bauxite can be changed into iron hydrogarnet if being processed with the additives of hydrated calcium ferrite, or calcium ferrite（Li et al,2006,2007,2010) [15,16].
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