Chromite is a dark gray to black oxide mineral composed of chromium, iron, and oxygen. It is the only economic ore of chromium, an essential element for many metal, chemical, and manufactured products. Learn about its …
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Elemental chromium (Cr) does not occur in nature but is present in ores, primarily as chromite (FeOCr 2 O 3). Around 90% of the mined chromite ore is converted into different grades of ferrochrome, while about 80% ferrochrome produced of mainly high-carbon or charged chrome grade are consumed by stainless steel industry. Chromium …
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Bauxite ore (Al 2 O 3.xH 2 O) is the major source of aluminium till date which is a mixture of hydrated aluminium oxide. Aluminium can also be recovered from cryolite (Na 3 AlF 6) and alunite. ... It is used in the extraction of manganese and chromium from its oxides.
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Modifications of EPA 3060A toward understanding the transformation of COPR minerals in the alkaline extraction and improving extraction of Cr( VI) from NIST SRM 2701, a standard COPR-contaminated soil resulted in a maximum release of 1274 ± 7 mg kg-1 Cr(VI). It has been shown that EPA Method 3060A does not adequately extract …
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Finally, iron, titanium, vanadium, chromium could be preliminarily separated via the solvent extraction by employing D2EHPA as the extraction agent. View Published by Elsevier B.V.
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The current strategy reports the recovery of precious group metals (PGMs) from Na2CO3 roast of Saudi Arabian ophiolitic chromite ore at 1160 °C under atmospheric O2. The influence of roasting temperature (960–1200 °C) and leaching agents (H2O, HCl, H2SO4) and their concentrations on the recovery of PGMs was studied. Chromite roast …
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EXTRACTION OF CHROMIUM FROM DOMESTIC CHROMITES BY ALKALI FUSION By Gary L. Hundley, 1 D. N. Nilsen, I and R. E. Siemens 2 ABSTRACT The Bureau of Mines has devised a procedure to recover chromium chemi ... cial ore of chromium, chromite, and must rely on imports to meet national needs. The chemical industry uses …
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Chromium is not mined in the United States. The chromium consumed by United States industry comes from: A) other countries in the form of chromite ore, ferrochromium or chromium metal; or, B) chromium recovered from recycled metals. Over half of the chromium used in the United States today is from recycling.
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Chromite deposits are mined by both underground and surface techniques. Much of the ore is rich enough to be used directly: for production of ferrochromium, a rich, lumpy ore containing more than 46 percent Cr2O3 and …
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Chrome ore is a mineral composed of chromium, iron and oxygen that is used to extract chromium for various applications. Learn about the different types of chrome ore deposits, the main sources in South Africa and …
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Chromite is an oxide mineral that an iron chromium oxide with formula: FeCr2O4. It is belonging to the spinel group. Chromite is the most important ore of chromium. Crystals are uncommon, but when found they are octahedral. Chromite is usually massive or in the form of lenses and tabular bodies, or it may be disseminated …
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To this end, the test and selection of the specific chemical reagent for efficient chromium extraction from phosphate ore were studied. The effects of some parameters were taken into consideration and optimized. The results show that the chromium content was reduced to approximately 30% in natural phosphate using citric …
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Chromium ore processing residue (COPR) is a hazardous waste generated during the production of chromate. Currently, approximately 10% of Cr 2 O 3 cannot be extracted after chromite sodium roasting and remains in COPR, wasting valuable Cr resources. In this study, Mg was selectively removed by using (NH 4) 2 SO 4 roasting in …
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(NH 4) 2 SO 4 roasting followed by water leaching to process nickel- chromium mixed metal oxidized (MO) ore was investigated. The optimal operating parameters were obtained after determining the influences of the molar ratio of (NH 4) 2 SO 4 to mixed oxidized ore, roasting temperature and roasting time on metal extractions. …
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Unfortunately, the formation of a molten state between the chromate ore particles at 1200 °C roasting temperature reduces the mass transfer rate of the oxygen (Yan et al., 2021), resulting in the low chromium extraction efficiency (approximate 85%) of this process for chromium and the larger energy consumption (Matern et al., 2020). …
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DOI: 10.1016/j.mineng.2020.106737 Corpus ID: 230586985; Extraction, phase transformation and kinetics of valuable metals from nickel-chromium mixed metal oxidized ore @article{Shen2020ExtractionPT, title={Extraction, phase transformation and kinetics of valuable metals from nickel-chromium mixed metal oxidized ore}, author={Xiao-yi Shen …
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The main raw material which is used for the extraction of chromium in China is chromite ore (Moon et al., 2009, Xu, 2011, Yu et al., 2015). The process involves conversion of insoluble Cr (III) in chromite ore to water soluble Cr(VI), thus separating chromium from other impurities (Qi, 2011).
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Commercial Extraction Technology and Process Waste Disposal in the Manufacture of Chromium chemicals From Ore. Published: September 2001; ... G. Commercial Extraction Technology and Process Waste Disposal in the Manufacture of Chromium chemicals From Ore. Environmental Geochemistry and Health 23, 187–193 (2001). …
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Post-extraction, the chromium ore undergoes various processing methods to eliminate impurities and isolate chromium from other elements. The extracted chromium serves …
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Overview of chromite ore processing. Chromite ore FeO·Cr 2 O 3 is a major ore for Chromium. India accounts for about 10% of world share of shipping grade Chromium ore reserves, having 45% Cr 2 O 3 content. South Africa and Zimbabwe and India are the Top five countries of Chrome ore processing industries in the Word (Indian …
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It has been shown that EPA Method 3060A does not adequately extract Cr(VI) from chromium ore processing residue (COPR). We modified various parameters of EPA 3060A toward understanding the transformation of COPR minerals in the alkaline extraction and improving extraction of Cr(VI) from NIST SRM 2701, a standard COPR …
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processed ore, with an average Cr 2 O 3 grade of less than 8%. At the Marula Mine, ore from the UG2 Reef is milled and processed to retrieve the PGMs at the PGM recovery plant of the mine. The Makgomo chrome recovery plant subsequently reprocesses the UG2 tailings generated by the PGM recovery plant to extract the chromitite. The plant has …
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Chromium ore processing residue (COPR) is a hazardous waste generated during the production of chromate. Currently, approximately 10% of Cr2O3 cannot be extracted after chromite sodium roasting ...
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1. Introduction. The international market for chromite ore (synthetic formula – FeO.Cr 2 O 3), the only commercially viable source of new chromium (Cr) units, is predominantly driven by the global demand for ferrochrome (FeCr).Secondary FeCr markets comprise of the Cr chemicals-, abrasives-, refractories-, and foundry sand …
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Chromium ore processing residue (COPR) is a hazardous waste generated during the production of chromate. Currently, approximately 10% of Cr 2 O 3 cannot be extracted after chromite sodium roasting and remains in COPR, wasting valuable Cr resources. In this study, Mg was selectively removed by using (NH 4) 2 SO 4 roasting in combination with …
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Chromium analysis of the solid residue showed that the extraction of chromium from the ore was 70.6%. Claims (9) I claim: 1. A process for extracting chromium in the form of a chromate from ore or concentrate by the suspension oxidation thereof to the chromate state which comprises suspending finely crushed ore or concentrate containing the ...
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Platinum (Pt) is a rare and valuable metal that is widely used in various industrial applications due to its unique properties. Platinum ore refers to the naturally occurring rocks or minerals that contain significant …
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other various products. Generally, the source of the chromium units is fer-rochromium or ferrochrome, which is primarily obtained from chromite ore. This ore represents a significant proportion of the known chromium reserves and also accounts for a large percentage of the current output [1, 2]. Metallurgical grade ore
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It has been shown that EPA Method 3060A does not adequately extract Cr(VI) from chromium ore processing residue (COPR). We modified various parameters of EPA 3060A toward understanding the transformation of COPR minerals in the alkaline extraction and improving extraction of Cr(VI) from NIST SRM 2701, a standard COPR …
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Chromium has a wide range of applications, including as an alloy addition in various steels and also as a corrosion resistance coating. Carbothermal reduction of chromite ore (FeCr 2 O 4) in a submerged arc furnace is an important industrial process for extracting chromium, but the energy consumption is excessive.It is suggested that one …
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Unfortunately, the formation of a molten state between the chromate ore particles at 1200 °C roasting temperature reduces the mass transfer rate of the oxygen (Yan et al., 2021), resulting in the low chromium extraction efficiency (approximate 85%) of this process for chromium and the larger energy consumption (Matern et al., 2020).
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Chromium is extracted from its ores by two processes. In the alkaline process, the finely ground ore is roasted with Na 2 CO 3 under oxidizing conditions at 1100 °C. The sodium …
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A novel reductive alkali roasting of chromite ores for carcinogen-free Cr 6+-ion extraction of chromium oxide (Cr 2 O 3) - A clean route to chromium product ... The novel extraction route may be able to displace the current oxidative process for chromite ore processing by retrofitting. Keywords: Chromite ore; Chromite ...
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Chromite ((ce{FeCr2O4})) is the most commercially useful ore, and is extensively used for extraction of chromium. Chromium is produced in two forms: Ferrochrome by the reduction of chromite with coke in an electric …
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Request PDF | Extraction, phase transformation and kinetics of valuable metals from nickel-chromium mixed metal oxidized ore | (NH4)2SO4 roasting followed by water leaching to process nickel ...
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