mechanical activation of chromite

Reactivity of Low-Grade Chromite Concentrates towards ...

The most economically important iron-chromium bearing minerals is chromite. In natural deposits, iron(II) is frequently substituted by magnesium(II) while chromium(III) is replaced by aluminum(III) and/or iron(III) forming a complex chromium bearing material. The majority of mined chromite is intended for the production of ferrochrome which requires a chromite concentrate with high …-【 ...2005-2-16 · Effect of mechanical activation on alkali leaching of chromite ore[J].:,2010,20(5):888-891. :4 5 JOHN M, KUBICEK D L. Sodium chromate and sodium dichromate production capacities [J].

Effect of mechanical activation on carbothermal reduction ...

2018-6-5 · Abstract. The carbothermal reduction of mechanically activated chromite with graphite under an argon atmosphere was investigated at temperatures between 1100 and 1400°C and the effects of the mechanical activation on chromite structure were analysed by X-ray diffraction, scanning electron microscopy and specific surface area measurement composition mechanism of chromite in sulfuric acid ...2017-5-19 · The sulfuric acid leaching process is regarded as a promising, cleaner method to prepare trivalent chromium products from chromite; however, the decomposition mechanism of the ore is poorly understood. In this work, binary spinels of Mg-Al, Mg-Fe, and Mg-Cr in the powdered and lump states were synthesized and used as raw materials to investigate the …

--UCAS

( 113 ) Effect of mechanical activation on alkali leaching of chromite ore, Transactions of Nonferrous Metals Society of China, 2010, 3 ( 114 ) Surface chemistry features in the flotation of KCl, Minerals Engineering, 2010, …--UCAS(12) Effect of mechanical activation on the alkali leaching of chromite ore, Transactions of Nonferrous Metals Society of China, 2010, 1 (13) Phase equilibria in the NaOH-NaNO3-Na2CrO4-H2O system, Journal of Chemical and Engineering Data, 2010, 1

Electrochemical enhanced oxidative decomposition of ...

2021-11-21 · Electrochemical enhanced oxidative decomposition of chromite ore in highly concentrated KOH solution Zhonghang Wanga,b, Hao Dua, Shaona Wanga, Shili Zhenga,⇑, Yi Zhanga, Seyeon Hwangc, Nam Soo Kimc, Tae Eui Jeongd a National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese …Exploring the Processing of Tubular Chromite- and …2019-1-13 · Exploring the Processing of Tubular Chromite- and ... † Current address: Department of Mechanical and Aerospace Engineering, University of Central Florida, 12760 Pegasus Blvd, P.O. Box 162450, Orlando, FL 32816-2450, USA. ... with the membrane and activation layers deposited on a thicker porous support [16]. Supports that are

Effect of mechanical activation on the soda roasting ...

The activation energies for the second step was calculated as 64.7 kJ/mol for non-activated chromite, 43 kJ/mol for 30 min activated chromite and 25.1 kJ/mol for 120 min activated chromite. Mechanical activation reduced the activation energy for the soda roasting of chromiteKinetics and mechanisms of the carbothermic reduction of ...2018-1-11 · Carbothermic reduction of chromite in the presence of nickel as the alloying element was investigated in a wide temperature range up to 1500 °C using thermogravimetric analysis coupled with continuous off-gas analysis (TG-DSC-MS). Both isothermal and non-isothermal linear heating tests were performed for the kinetic study with the calculation of activation …

[PDF] Effects of Mechanical Activation on the Bioleaching ...

Even though mechanical activation is a significant pretreatment technology for the efficient extraction of metals from mineral resources, its effects on the bioleaching of sphalerite and marmatite are rarely discussed. In this study, mechanical activation pretreatment using various grinding media and grinding times was conducted, and particle size distribution, morphology, X …Leaching of chromite ore in concentrated KOH by catalytic ...2017-4-1 · Abstract CuO was used as a catalyst in the concentrated KOH solution to enhance the leaching of chromium from the chromite ore. The impacts of temperature, KOH-to-chromite ore mass ratio, CuO-to-chromite ore mass ratio, and gas flow rate on the chromium leaching rate were investigated. The results indicated that CuO played an important role in improving the …

Sakarya Üniversitesi | Sakarya Üniversitesi | Prof.Dr ...

1.3-SSCI, SCI-EXP, AHCI, ESCI DIŞINDAKİ ALAN ENDEKSLERİNDEKİ DERGİLERDE YAYIMLANAN TAM MAKALE : 1: Yarkadas, G.; Yildiz, K. - Effects of mechanical activation on alumina extraction from alunite ore and its thermal behaviour - Transactions of the Institutions of Mining and Metallurgy, Section C: Mineral Processing and Extractive Metallurgy - Vol.117 - …CHEMICAL COMPOSITION OF NEW ACAPULCOITES AND …2009-2-28 · Mobilisation of chromite, indicated by high Cr in Acapulco and low Cr in MD, requires a high degree of partial melting to allow mechanical separation of chromite crystals. From the different composition of matrix metal and tiny metal inclusions inside olivine and orthopyroxene

Effects of Mechanical Activation on the Soda Roasting of ...

2013-7-18 · The effects of mechanical activation on the soda roasting of chromite were investigated in this study. Structural changes in mechanically activated chromite were examined using X-ray diffraction analysis (XRD), surface area analysis (BET) and scanning electron microscopy (SEM).Effect of mechanical activation on alkali leaching of ...2010-5-1 · Mechanical activation was used to improve the extraction of chromium in molten NaOH. It is observed that the extraction ratio reaches 97% after leaching for 200 min when chromite ore is mechanically activated for 10 min, but only 34% if not activated. Mechanical activation can decrease the particle size, increase the surface area, and enhance ...

Leaching of chromite ore in concentrated KOH by …

2017-5-4 · Leaching of chromite ore in concentrated KOH by catalytic oxidation using CuO as catalyst ... the catalytic oxidation was controlled by surface chemical reaction and the activation energy was calculated to be 15.79 kJ/mol when the temperature was above 230 °C. ... mechanical agitator (D−8401WZ) was used to keep the slurry suspended during ...Leaching of Valuable Elements from the Waste Chromite …2020-8-11 · chromite ore processing residue (COPR) is an inevitable solid emission in chromite salt production. It is an industrial waste produced during the extraction of Cr(VI) from a chromite ore using the high-temperature roasting process.11 In general, the COPR is alkaline (pH > 12),5,7 and because of the presence of partially water-soluble ...

Unveiling the Role and Mechanism of Mechanochemical ...

2018-9-12 · This research presented the impacts of mechanochemical activation (MCA) on the physiochemical properties of lithium cobalt oxide (LiCoO2) powders of cathode materials from spent lithium-ion batteries, and analyzed the relevant effects of these changes on the leaching efficiency of lithium and cobalt and the leaching kinetics of LiCoO2 powders. The results …Compressive creep of basic refractories2020-10-13 · and.adjacent chromite grains with well dispersed large voids.5 The periclase - chromi te direct bond is considered due to the interdiffusion and reaction . of . RO and R2. o. 3 . compounds such as MgO, cr. 2. o. 3, and Fe2. o. 3• Direct bonded basic refractories have good chemical durability, i.e., slag resistance, and mechanical strength at ...

CHROMIUM OBTAINING FROM ARMENIAN CHROMITE …

2017-5-22 · Chromium obtaining from armenian chromite concentrates by SHS in the presence of chlorides 33 CHROMIUM OBTAINING FROM ARMENIAN CHROMITE ... XRD patterns for washed chromite samples after 120 min activation in the presence of NaCl MgO – 7,39%, SiO2 – 4,15%, CaO –2,24%. This ... due to the mechanical effect[10]. ...Messengers from the deep: Fossil wadsleyite-chromite ...2015-11-13 · The sample consists of two zones: Zone 1 contains larger chromite grains (591vm vs 526 μm) with slightly higher median aspect ratios (1.73 vs 1.70) and lower abundance of olivine (1.6 area% vs 2 ...

Effect of mechanical activation on alkali leaching of ...

Effect of mechanical activation on alkali leaching of chromite ore. Author links open overlay panel Yang ZHANG a b Shi-li ZHENG a Hao DU a Hong-bin XU a Yi ZHANG a. Show more lphuric acid leaching of mechanically activated copper ...Yarkadaş and Yildiz (2009) studied the effect of mechanical activation on soda roasting of chromite and could improve the conversion from 18% …

Effect of mechanical activation on alkali leaching of ...

Mechanical activation was used to improve the extraction of chromium in molten NaOH. It is observed that the extraction ratio reaches 97% after leaching for 200 min when chromite ore is ...Effect of mechanical activation on alkali leaching of …2010-5-18 · Effect of mechanical activation on alkali leaching of chromite ore ZHANG Yang( )1, 2, ZHENG Shi-li()1, DU Hao( )1, XU Hong-bin()1, ZHANG Yi( )1 1. National Engineering Laboratory for Hydrometallurgical Cleaner

2015251-《 ...

Re-oxidation mechanism of chromite roasting in late stages CHEN Yong-an WANG Wu-yu, LI Ping, ZHENG Shi-li, ZHANG Xiang-dong, CHE Xiao-kui, ZHANG Yi 203 Effect of mechanical activation on hydrochloric acid leaching ilmenite at atomospheric pressureEFFECT OF MECHANICAL ACTIVATION ON THE …2016-10-17 · tation, mechanical activation and the aerosol method.1 Mechanical activation is a method, which can induce changes tothe solid-state properties, such as the distor-tion of the structure, accompanied by the accumulation of energy and the formation of active centers on the newly formed surfaces.5 Different processes can remark-

Effect of mechanical activation on carbothermal reduction ...

2018-6-5 · Abstract. The carbothermal reduction of mechanically activated chromite with graphite under an argon atmosphere was investigated at temperatures between 1100 and 1400°C and the effects of the mechanical activation on chromite structure were analysed by X-ray diffraction, scanning electron microscopy and specific surface area measurement.1,2, 1,2 3 - res.mdpi 2020-5-19 · grams of chromite powder (<74 m) was added to the vessel when the solution heated to the set point (160, 180, and 200 °C, respectively). After 60 min mechanical agitation, the leachate was removed from the heater and a filtration was carried out. Th e concentrations of metallic ions were determined

--UCAS

( 113 ) Effect of mechanical activation on alkali leaching of chromite ore, Transactions of Nonferrous Metals Society of China, 2010, 3 ( 114 ) Surface chemistry features in the flotation of KCl, Minerals Engineering, 2010, 2 --UCAS2019-11-22 · (143) Effect of mechanical activation on the alkali leaching of chromite ore, Transactions of Nonferrous Metals Society of China, 2010, (144) Phase equilibria in the NaOH-NaNO3-Na2CrO4-H2O system, J. Chem. Eng. Data, 2010,

Influence of mechanical activation of basic refractories ...

Mechanical activation leads to partial breakdown of the crystalline structures of refractory materials, conferring a higher reaction state on them. This is manifest as a reduction in the temperature range in which the magnesite and dolomite undergo conversions during heating, and also in the greater degree of exposure of the periclase and chrome concentrate.The porosity …Decomposition mechanism of chromite in sulfuric acid ...2017-5-19 · The sulfuric acid leaching process is regarded as a promising, cleaner method to prepare trivalent chromium products from chromite; however, the decomposition mechanism of the ore is poorly understood. In this work, binary spinels of Mg-Al, Mg-Fe, and Mg-Cr in the powdered and lump states were synthesized and used as raw materials to investigate the …

Effects of Mechanical Activation on the Bioleaching ...

2021-1-23 · Even though mechanical activation is a significant pretreatment technology for the efficient extraction of metals from mineral resources, its effects on the bioleaching of sphalerite and marmatite are rarely discussed. In this study, mechanical activation pretreatment using various grinding media and grinding times was conducted, and particle size distribution, …EFFECT OF MECHANICAL ACTIVATION ON THE …2016-10-17 · tation, mechanical activation and the aerosol method.1 Mechanical activation is a method, which can induce changes tothe solid-state properties, such as the distor-tion of the structure, accompanied by the accumulation of energy and the formation of active centers on the newly formed surfaces.5 Different processes can remark-

Performance evaluation of commercial copper chromites …

2011-7-23 · identify chromite anion bands and also the bands of the raw materials (reagents) used to synthesize the copper chromite by the ceramic or co-precipitation method. The bands at 614 and 524 cm-1, attributed to the Cr 2 O 4 = anion, are related to the copper chromite prepared by ceramic method. The bands related to the copper chromiteSintering of Cobalt and Strontium Doped Lanthanum …Lanthanum chromite (LaCrO3) is one of the most adequate materials for use as interconnector in solid oxide fuel cell (SOFC) applications, due to its intrinsic properties, namely its good electrical conductivity and resistance to environment conditions in fuel cell operations. Due to difficulties in sintering, additives are usually added to help in the densification process.

Decomposition mechanism of chromite in sulfuric acid ...

2017-12-13 · The sulfuric acid leaching process is regarded as a promising, cleaner method to prepare trivalent chromium products from chromite; however, the decomposition mechanism of the ore is poorly understood. In this work, binary …Decomposition mechanism of chromite in sulfuric acid ...2017-5-19 · The sulfuric acid leaching process is regarded as a promising, cleaner method to prepare trivalent chromium products from chromite; however, the decomposition mechanism of the ore is poorly understood. In this work, binary spinels of Mg-Al, Mg-Fe, and Mg-Cr in the powdered and lump states were synthesized and used as raw materials to investigate the …