Showing 01 - 12 of 139 Results

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An efficient utilization of chromium–containing vanadium

Aug 15, 2019· An efficient utilization of chromium–containing vanadium tailings: Extraction of chromium by soda roasting–water leaching and preparation of chromium oxide. Author links open overlay panel Jing Wen a Tao Jiang a b Huiyang Gao a Wanying Zhou a Yingzhe Xu a Xiaole Zheng a Yajing Liu a Xiangxin Xue a b.

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Selective recovery of chromium from ferronickel slag via

Jul 15, 2019· Chromium was selectively recovered from ferronickel slag by roasting the slag with addition of Na 2 O 2, followed by water leaching.The thermodynamic analysis revealed that in the presence of Na 2 O 2 at appropriate temperatures, the Cr 2 O 3 in the ferronickel slag can be converted to NaCrO 2, instead of Na 2 CrO 4, which prevents the formation of highly toxic Cr (VI).

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A literature review on leaching and recovery of vanadium

Stepwise sodium roasting-water leaching technology was applied to recover vanadium and chromium from high-chromium vanadium slag. About 87.9% of the vanadium could leach out at first step of Na 2 CO 3-roasting-water-leaching at roasting temperature of 800 ℃ for 120 min.

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Comparative study of alkali roasting and leaching of

Organic acid leaching Extraction of titanium and chromium oxides may be achieved via roasting the respective minerals with alkali at high temperatures, followed by water and organic acid le aching. In this study, sodium and potassium hydroxides are used as alkali for roasting of chromite ores and ilmenit e mineral concentrates.

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roasting and leaching processess for chromium

Roasting And Leaching Processess For Chromium. roasting and leaching processess for chromium; roasting and leaching processess for chromium Final Report, a chrome ore roasting process for the recovery of the . Rock Phosphate Roasting Mining Machinery. Rock Phosphate Roasting, Since phosphate rock is not a pure material but contains varying

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Comparative study of alkali roasting and leaching of

Comparison of alkali roasting and leaching of chromite ores and titaniferous minerals was carried out • Roasting temperature and time were studied using KOH and NaOH salts for both minerals • 95% of chromium recovery was achieved by roasting with NaOH and KOH at 1000 °C and subsequent water leaching •

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A novel roasting process to extract vanadium and chromium

Nov 05, 2019· To roast high chromium vanadium slag using a microwave heating furnace. • The conversion of vanadium and chromium was significantly affected by roasting temperature and time. • The optimal leaching rates of vanadium and chromium were 94.11% and 90.81%. • The major mineralogical phases of the residue were Fe 2 O 3, Na 2 TiO 3, NaFeSiO 4. •

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A novel roasting process to extract vanadium and chromium

Nov 05, 2019· To roast high chromium vanadium slag using a microwave heating furnace. • The conversion of vanadium and chromium was significantly affected by roasting temperature and time. • The optimal leaching rates of vanadium and chromium were 94.11% and 90.81%. • The major mineralogical phases of the residue were Fe 2 O 3, Na 2 TiO 3, NaFeSiO 4. •

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Roasting and leaching behaviors of vanadium and chromium

Calcification roasting-acid leaching of high-chromium vanadium slag (HCVS) was conducted to elucidate the roasting and leaching behaviors of vanadium and chromium. The effects of the purity of CaO, molar ratio between CaO and V2O5 ( n(CaO)/ n

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Roasting and leaching behaviors of vanadium and chromium

Calcification roasting–acid leaching of high-chromium vanadium slag (HCVS) was conducted to elucidate the roasting and leaching behaviors of vanadium and chromium. The effects of

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Chromium Wikipedia

For the production of pure chromium, the iron must be separated from the chromium in a two step roasting and leaching process. The chromite ore is heated with a mixture of calcium carbonate and sodium carbonate in the presence of air. The chromium is oxidized to the hexavalent form, while the iron forms the stable Fe 2 O 3.

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Mineral processing: leaching process of chromium and

The un reacted chromium oxide remained in the chromite roast with the refractory oxides and ends up in the waste stream for landfills. ICP-OES analysis of the roast reduces after leaching was used to calculate the extraction yield according to the following equation:

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chrome roasting and leaching process ifoza.nl

roasting and leaching processess for chromium. roasting and leaching processess for chromium The Effect of Chromium on the Roasting Process Semantic Scholar Jul 9, 2016 NaCl, Na2SO4, and Na2CO3 as additives [913] The representative vanadium extraction route mainly consists of the following procedures: sodium salt roasting, water leaching, solution purifiion and V precipitation [5].

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(PDF) Mineral processing: leaching process of chromium and

Mineral processing: leaching process of chromium and recovery of platinum group elements from Northwestern Saudi Arabian Ophiolitic chromite. plex minerals using alkali roasting and leaching

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chrome roasting and leaching process

Microwave Roasting and Acid Leaching of Vanadium and While the leaching ratio of chromium is 3.98%. During roasting process, vanadium is oxidized to acid-soluble CaV2O5, Ca2V2O7, and CaMgV2O7. After leaching, chromium mainly exists in form of chromohercynite (FeCr2O4) and chrome-manganese spinel (Mn1.5Cr1.5O4) in leaching residues.

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roasting and leaching processess for chromium

Roasting And Leaching Process For Chromium pallring. A green and efficient process for extracting chromium C followed by water leaching. About 5% of chromium and 85% of leaching residue containing high the pellet during roasting and a. roasting and leaching processess for chromium.

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Leaching of vanadium and chromium from converter vanadium

Technology intensified with surface wettability was introduced to leach vanadium and chromium from converter vanadium slag without roasting. Parameters affecting the leaching efficiency of

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The Effect of Chromium on the Roasting Process of

the influence of chromium on roasting vanadium slag. Samples were characterized by XRD, thermal analysis and SEM at different temperatures: Cr2O3 and Na2CO3 began to react at 500 C. When the sodium salt roasting, water leaching, solution purification and V precipitation [5].

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Preventing Chromium Leaching

The result suggests that the gypsum barrier, if it exists, dissolves in the stronger acid to allow normal chromium leaching. In figures 3 and 4, the chromium leach-ability increases as the CaO:SiO2 ratio is decreased below the range around 1.2 to 1.3, the level of minimum leachability.

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(PDF) The Effect of Chromium on the Roasting Process of

We simulated the roasting process of chromium by mixing Cr2O3 and Na2CO3 to analyze the influence of chromium on roasting vanadium slag. Samples were

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Gold Metallurgy & Leaching in Cyanicides

Cyanidation as applied to ordinary gold and silver ores is a relatively simple process. When cyanicides {cyanide-consuming elements) are encountered in small amounts in the treatment of such ores, the various schemes already discussed, such as use of a lead salt or wasting barren solution, can usually be resorted to and successful operation maintained.

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chrome roasting and leaching process

Microwave Roasting and Acid Leaching of Vanadium and While the leaching ratio of chromium is 3.98%. During roasting process, vanadium is oxidized to acid-soluble CaV2O5, Ca2V2O7, and CaMgV2O7. After leaching, chromium mainly exists in form of chromohercynite (FeCr2O4) and chrome-manganese spinel (Mn1.5Cr1.5O4) in leaching residues.

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roasting and leaching processess for chromium

Roasting And Leaching Process For Chromium pallring. A green and efficient process for extracting chromium C followed by water leaching. About 5% of chromium and 85% of leaching residue containing high the pellet during roasting and a. roasting and leaching processess for chromium.

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The Effect of Chromium on the Roasting Process of

the influence of chromium on roasting vanadium slag. Samples were characterized by XRD, thermal analysis and SEM at different temperatures: Cr2O3 and Na2CO3 began to react at 500 C. When the sodium salt roasting, water leaching, solution purification and V precipitation [5].

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Physical Chemistry of Roasting and Leaching Reactions for

The natural resource of chromium is the chromite ore, which is a spinel (Fe 2+, Mg)[Cr,Al,Fe 3+] 2 O 4, and is often present with gangue minerals such silicates. Traditionally chromium chemical extraction has been carried out with alkali and CaO roasting, which led to major environmental issues due to CaCrO 4 /Na 2 CrO 4 release.

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Indicative Vanadium Deportment in the Processing of

Roast–Leach Experiments The roast–leach testwork conducted at Mintek adopted the soda ash roasting and water leaching approach because this option is reportedly most common in industrial applications (Mefos, 2006). Roasting The roasting conditions were deduced from the best roasting conditions established at Mintek in the

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chrome roasting and leaching process MC Machinery

Roasting And Leaching Process For Chromium. chrome roasting and leaching process . Jun 15, 2015 For the production of pure chromium the iron has to be separated from the chromium in a two stage roasting and leaching process Ferroalloys The Effect of Chromium on the Roasting Process

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(PDF) Comparative study of alkali roasting and leaching of

Extraction of titanium and chromium oxides may be achieved via roasting the respective minerals with alkali at high temperatures, followed by water and organic acid leaching.

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Preventing Chromium Leaching

The result suggests that the gypsum barrier, if it exists, dissolves in the stronger acid to allow normal chromium leaching. In figures 3 and 4, the chromium leach-ability increases as the CaO:SiO2 ratio is decreased below the range around 1.2 to 1.3, the level of minimum leachability.

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(PDF) The Effect of Chromium on the Roasting Process of

We simulated the roasting process of chromium by mixing Cr2O3 and Na2CO3 to analyze the influence of chromium on roasting vanadium slag. Samples were

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Gold Metallurgy & Leaching in Cyanicides

Cyanidation as applied to ordinary gold and silver ores is a relatively simple process. When cyanicides {cyanide-consuming elements) are encountered in small amounts in the treatment of such ores, the various schemes already discussed, such as use of a lead salt or wasting barren solution, can usually be resorted to and successful operation maintained.

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Extracting Chromium from Stainless Steel Slags by NaOH

In the second roasting stage, sodium salt, which combines with chromium easily, was added to the first leaching residue to extract chromium and 95.16 pct chromium was extracted under the optimal

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Microwave Roasting and Acid Leaching of Vanadium and

While the leaching ratio of chromium is 3.98%. During roasting process, vanadium is oxidized to acid-soluble CaV2O5, Ca2V2O7, and CaMgV2O7. After leaching, chromium mainly exists in form of chromohercynite (FeCr2O4) and chrome-manganese spinel (Mn1.5Cr1.5O4) in leaching residues.

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Leaching and recovery of platinum group metals from UG

Leaching and recovery of platinum group metals from UG-2 concentrates yields were not good (less than 40 per cent). Platinum leaching was particularly poor with cyanide (ambient temperature). A HCl/chlorine leach on untreated material had the same effect as a cyanide leach with a nitric acid pre-leach,

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What is CHROMIUM? YouTube

Nov 15, 2018· Ferrochromium alloy is commercially produced from chromite by silicothermic or aluminothermic reactions and chromium metal by roasting and leaching processes followed by reduction with carbon and

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(PDF) Comparative study of alkali roasting and leaching of

Extraction of titanium and chromium oxides may be achieved via roasting the respective minerals with alkali at high temperatures, followed by water and organic acid leaching.

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Extracting Chromium from Stainless Steel Slags by NaOH

In the second roasting stage, sodium salt, which combines with chromium easily, was added to the first leaching residue to extract chromium and 95.16 pct chromium was extracted under the optimal

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Microwave Roasting and Acid Leaching of Vanadium and

While the leaching ratio of chromium is 3.98%. During roasting process, vanadium is oxidized to acid-soluble CaV2O5, Ca2V2O7, and CaMgV2O7. After leaching, chromium mainly exists in form of chromohercynite (FeCr2O4) and chrome-manganese spinel (Mn1.5Cr1.5O4) in leaching residues.

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What is CHROMIUM? YouTube

Nov 15, 2018· Ferrochromium alloy is commercially produced from chromite by silicothermic or aluminothermic reactions and chromium metal by roasting and leaching processes followed by reduction with carbon and

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Efficient Separation and Extraction of Vanadium and

In the second roasting stage, sodium salt, which combines with chromium easily, was added to the first leaching residue to extract chromium and 95.16 pct chromium was extracted under the optimal conditions. The total vanadium and chromium leaching rates were above 95 pct, achieving the efficient separation and extraction of vanadium and chromium.

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Study on the Roasting Mechanism of Vanadium–Chromium Slag

Wen J, Jiang T, Xu Y et al (2018) Efficient separation and extraction of vanadium and chromium in high chromium vanadium slag by selective two-stage roasting-leaching. Metall Mater Trans B 49(3):1471–1481 CrossRef Google Scholar

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How to Recover Chrome Metal from Scrap Alloy

This alternative procedure is based on the observation that dissolution of chromium sulfide can be suppressed by limiting the redox potential during leaching. The chromium-rich residue of such a direct leach process would be treated to produce chromium metal using fluidized-bed roasting and aluminothermic reduction.

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CN103614566A Method for extracting vanadium and chromium

The invention discloses a method for extracting vanadium and chromium from converter vanadium chromium slag. The method comprises the following steps: 1) adding Na2CO3 into the vanadium chromium slag, mixing uniformly and carrying out oxidizing roast on the mixture, wherein the addition of Na2CO3 is controlled according to a molar ratio of V2O3/Na2CO3 in the vanadium chromium slag

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chrome roasting and leaching process

leaching processleaching process for chromite houtenclara.be. leaching with caustic of the chromite plant, Mining Processing Plant for Stone Chrome High caustic of the chromite plant chrome roasting and leaching process; Live Chat Caustic Leaching of Hanford Tank T-110 Sludge

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Leaching and recovery of platinum group metals from UG

Leaching and recovery of platinum group metals from UG-2 concentrates yields were not good (less than 40 per cent). Platinum leaching was particularly poor with cyanide (ambient temperature). A HCl/chlorine leach on untreated material had the same effect as a cyanide leach with a nitric acid pre-leach,

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Stainless Steel Leaches Nickel and Chromium into Foods

Oct 02, 2013· Additional dietary sources, such as leaching from stainless steel cookware during food preparation, are not well characterized. This study examined stainless steel grades, cooking time, repetitive cooking cycles, and multiple types of tomato sauces for their effects on nickel and chromium leaching.

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Chromium Video Learning WizScience YouTube

Sep 08, 2015· Chromium metal and ferrochromium alloy are commercially produced from chromite by silicothermic or aluminothermic reactions, or by roasting and leaching processes. Chromium

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chrome roasting and leaching process south africa and

A flowsheet has been developed for the production of rich concentrates of precious and non-ferrous metals by a complex treatment of the flotation products from South African platinum-containing chrome or The procedure involves: autoclave leaching, roasting, hydrochlorination and precious metal recovery by sorption Autoclave oxidative leaching

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An alkaline roast-leach process for treatment of

Aluminum was recovered by precipitation.The present paper describes the roast-leach bench-scale and pilot-plant work leading to the development of the optimum conditions for the integrated process.A plant flowsheet was developed for the treatment of 5 x 106 tons of magnetic concentrate per annum.