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leaching process for chromite

A clean and efficient leaching process for chromite ore ...

The leaching process was controlled by inner diffusion, and the activation energy was calculated to be 55.6 kJ/mol in the temperature range of 280–370 °C. Download : Download full-size image; Fig. 10. Arrhenius plot for the leaching process of Philippine chromite ore.

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A clean and efficient leaching process for chromite ore ...

During the leaching process, other accompanying elements such as aluminum and silicon were extracted out from the chromite ore as well. However, their leaching products easily formed a

Acid leaching of chromite - ScienceDirect

Acid leaching of chromite 611 o -3.6 -3.8 -4.0 -4.2 4 -4.4 * -4.6 4, . -4.8 -5.0 -5.2 - -5.4 , , , , , , 2.05 2.10 2.15 2.20 2.25 2.30 2.35 IO00/'I'(K) 2.40 Fig.4 Arrhenius plot for leaching of chromite at a temperature range of 140210, 77 weight percent of sulphuric acid without addition of perchloric acid for a leaching time of 6 hours. Ea = 75.86 kJ/mol The extraction rate of chromium with ...

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Recovery of chromium from residue of sulfuric acid ...

The sulfuric acid leaching process is widely considered to be a cleaner technology to prepare chromium salt from natural chromite as no Cr(VI)-bearing wastes are generated or discharged. However, some insoluble anhydrous chromium sulfate could precipitate causing a serious chromium resource loss and potential pollution problems. For the purpose of recovery of chromium from leaching residue, a ...

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Sulfuric acid leaching of South African chromite. Part 1 ...

10/07/2014  Another cleaner process beyond the proof of concept stage for processing chromite and other refractory ores (Bayca, 2013, Li et al., 2008) is the acid leaching process. It shows that chromite dissolves in concentrated sulfuric acid below 200 °C in the presence of oxidant without generating any chromium (VI)-bearing substance ( Ji, 2012 ).

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Recovery of chromium and magnesium from spent

In this study, recovery of chromium and magnesium from spent magnesia-chrome refractories was developed by acid leaching combined with alkali precipitation and evaporation. The optimized conditions for leaching were found to be particle size of −74 + 38 μm, hydrochloric acid solution of 5.0 mol/L, liquid-solid ratio of 5:1, leaching temperature of 343 K, leaching time of 90 min and ...

Author: Fen Jiao, Wei Li, Kai Xue, Congren Yang, Wenqing Qin

Comparative study of alkali roasting and leaching of ...

Comparative study of alkali roasting and leaching of chromite ores and titaniferous minerals Stephen Parirenyatwa ... the roasting process is discussed in terms of designing the process. Samples of chromite and titaniferous minerals were roasted with NaOH and KOH in a temperature range of 400 °C–1000 °C in an oxidising atmosphere. The roasted chromite and ilmenite samples were further ...

(PDF) Leaching of chromite ore in concentrated KOH by ...

The leaching process of chromite ore is a typical LO reaction, and the oxygen mass transfer in the KOH sub-molten salt solution is a vital factor.

Leaching Mechanisms of Cr(VI) from Chromite Ore

Batch leaching tests, qualitative and quantitative x-ray powder diffraction (XRPD) analyses, and geochemical modeling were used to investigate the leaching mechanisms of Cr(VI) from chromite ore ...

Preventing Chromium Leaching

The effect of lime addition on chromium leachability from waste slag has a counterpart in the well-known process of chemical extraction of chromite (FeOCr2O3) ores. In this case, high chromium leachability is desired and is aided by the addition of lime to a mixture of chromite ore and Na2CO3. The CaO-Na2CO3 ore mixture is roasted at 1,100° to 1,150° C in an oxidizing air atmosphere ...

Leaching Mechanisms of Cr(VI) from Chromite Ore

Batch leaching tests, qualitative and quantitative x-ray powder diffraction (XRPD) analyses, and geochemical modeling were used to investigate the leaching mechanisms of Cr(VI) from chromite ore ...

Preventing Chromium Leaching

The effect of lime addition on chromium leachability from waste slag has a counterpart in the well-known process of chemical extraction of chromite (FeOCr2O3) ores. In this case, high chromium leachability is desired and is aided by the addition of lime to a mixture of chromite ore and Na2CO3. The CaO-Na2CO3 ore mixture is roasted at 1,100° to 1,150° C in an oxidizing air atmosphere ...

Recovery of chromium from residue of sulfuric acid ...

A new leaching process for preparing chromium oxide from chromite was studied for this paper, using Cr(VI) extracted from the remediation treatment of chromite ore processing residue (COPR) as an ...

Extraction of Chromium from Chromite Ore

Chemical-grade chromite ore generally ranged from 40 to 46 pct Cr2O3 with a chromium-to-iron ratio of 1.5:1 to 2:1. Refractory-grade chromite ores contained a minimum of 20 pct Al2O3 and more than 60 pct Al2O3 plus Cr2O3. Primary chromium needs for all uses in the United States by the year 2000 are estimated to be nearly three times its present annual consumption (400,000 short tons), and ...

Mineral processing: leaching process of chromium and ...

The current strategy reports the recovery of precious group metals (PGMs) from Na 2 CO 3 roast of Saudi Arabian ophiolitic chromite ore at 1160 °C under atmospheric O 2.The influence of roasting temperature (960–1200 °C) and leaching agents (H 2 O, HCl, H 2 SO 4) and their concentrations on the recovery of PGMs was studied.Chromite roast concentrates a reasonable percentage of ...

Leaching Process For Chromite - gobeyondmba.nl

Leaching Process For Chromite - greenrevolution. leaching process for chromite,leaching procedure for chromite Chromite . Chromite is an iron chromium oxide: FeCr 2 O 4. It is an oxide mineral belonging to the spinel group. Magnesium can substitute for iron in variable amounts .

Chromite Beneficiation Process

Chromite Process Summary. This flowsheet is very effective due to the ability to remove the high grade chrome with very little grinding on each pass through the mill. In this way, grinding takes place with a large number of small reductions followed by immediate

(PDF) Sulfuric acid leaching of Turkish chromite

A new leaching process for preparing chromium oxide from chromite was studied for this paper, using Cr(VI) extracted from the remediation treatment of chromite ore processing residue (COPR) as an ...

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.

Leaching of hexavalent chromium from young chromite

3.2 Chromite ore processing residue leaching behavior Figures 1 and 2 show the results of the COPR leaching as a function of the number of PV exchanged (dimensionless time). Aqueous concentrations of Al, Cr(III), Fe, Mg, and Si are not shown, since their concentrations were very low (Fe, Mg, and Si were below the limit of determination by ICP–OES; 10 μg L −1 ).

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.

Leaching of hexavalent chromium from young chromite

3.2 Chromite ore processing residue leaching behavior Figures 1 and 2 show the results of the COPR leaching as a function of the number of PV exchanged (dimensionless time). Aqueous concentrations of Al, Cr(III), Fe, Mg, and Si are not shown, since their concentrations were very low (Fe, Mg, and Si were below the limit of determination by ICP–OES; 10 μg L −1 ).

leaching process for chromite - z.miningbmw

Home > Process > leaching process for chromite. leaching process for chromite. Chromite - Wikipedia, the free encyclopedia. Chromite is an iron chromium oxide: FeCr2O4. It is an oxide mineral belonging to the spinel group. Magnesium can substitute for iron in variable amounts as it forms a ... Leaching and recovery of platinum group metals from UG Leaching and recovery of platinum

Advances towards a Clean Hydrometallurgical Process

The sulfuric acid leaching behavior of the chromite in Zhao et al. ’s study can be illustrated as shown in Figure 3, where four types of spinel, denoted as I, II, III, and IV, represent different states at specific stages of the leaching process. Spinel I shows that the particle becomes smaller with the duration of the leaching. Three corrosion depths marked as

Sulfuric acid leaching kinetics of South African chromite ...

The sulfuric acid leaching kinetics of South African chromite was investigated. The negative influence of a solid product layer constituted of a silicon-rich phase and chromium-rich sulfate was eliminated by crushing the chromite and by selecting proper leaching conditions. The dimensionless change in specific surface area and the conversion rate of the chromite were observed to exhibit a ...

Chomite ore processing plants, CDE Global

The process of chromite ore mining can be divided into 2 areas: 1. Feed preparation . 2. Concentration. The feed preparation stage involves the introduction of various physical separation equipment including crushers, screens and grinding mills. The principal function of this stage is size reduction in preparation for the concentration phase. The concentration phase introduces hydrocyclone ...

Experimental Study on Sulfuric Acid Leaching Behavior

Utilizing Pakistan chromite as raw material, the rapid leaching of chromium and iron could be realized by the sulfuric acid leaching process on the condition of atmospheric pressure and the addition of oxidant A. And the leaching rate of chromium and iron would be 98.5% and 71.9%, respectively. The sulfuric acid leaching processes with different temperature were systematically studied by ...

leaching process for chromite - Popular Education

Key words: Leaching, Chromite, Hexavalent chromium, Sulfuric acid, Perchloric acid. Introduction .... Experimental set-up of the leaching process. Results and... Read More. Chromite ore processing equipment from CDE Mining . our chromite ore processing equipment can be used to effectively remove unwanted ... ore prior to material being stacked before the heap leaching process. Read More. A ...

leaching process for chromite saudi arabia - OCMD

leaching process for chromite saudi arabia. Bauxite Grinding Process Process Crusher, Mining Equipment ... Bauxite Grinding Process ... Egypt, Liberia, Sri Lanka, Zambia, Chile, Spain, France, Peru, Vietnam, Angola, Saudi Arabia ... Chromite mining process,Chromite ... aluminothermic reaction process for chromium ore - Coal ... If you need more information about aluminothermic reaction ...

LEACHABILITY OF CHROME FROM MNESIA-CHROMITE

LEACHABILITY OF CHROME FROM MNESIA-CHROMITE REFRACTORY BRICKS CORRODED BY Cu/CuO-Na 2 O2SiO 2 SLS #DÁVID MEDVEĎ, PAVOL VADÁSZ, BEATRICE PLEŠINGEROVÁ, MAREK VOJTKO, EVA GRAMBÁLOVÁ Faculty of Metallurgy, Technical University of Košice, Letná 9, SK – 042 00, Slovakia #E-mail: [email protected] Submitted February 25, 2015; accepted June