ferrochrome slag trivalent and hexavalent chromium

2018-01-04T03:01:38+00:00
  • ferrochrome slag trivalent and hexavalent chromium

    Biological Reduction of Hexavalent Chromium: A Field Study. process also generates slag and an offgas dust, which is deposited at a site near the plant. The dust contains chromium, mainly in the trivalent form (Cr3^), but with a minor fraction as hexavalent chromium (Cr6+). Chromium is leached when rainwater percolates. Get Price

  • ferrochrome slag trivalent and hexavalent chromium

    Stability of chromium in the ferrochrome slag dumps and leachate are affected by pH, redox potential and the presence of other metallic species in the slag. It is desirable to keep chromium in slag dumps in the trivalent [Cr(III)] state because trivalent chromium is 1000 times less toxic to living organisms than the hexavalent form [Cr(VI)]. More

  • Hexavalent chromium removal by ferrochromium slag ...

    2005-11-11  The reduction of hexavalent chromium by metallic components of slag in acidic solutions can be expressed by following equation: (1) 2[xFeyCr] + (x + y)Cr 2 O 7 2− + 14(x + y)H + → 2xFe 3+ + 2(x + 2y)Cr 3+ + 7(x + y)H 2 O where x and y are stoichiometric coefficients. It must be denoted that the amount of acid to be used in reduction process is the most important parameter because of the fact that the basic components of slag

  • Cited by: 74
  • Hexavalent chromium removal by ferrochromium slag.

    2005-11-11  Hexavalent chromium removal by ferrochromium slag. Erdem M(1), Altundoğan HS, Turan MD, Tümen F. Author information: (1)Department of Environmental Engineering, Firat University, 23279 Elaziğ, Turkey. The aim of this study is to demonstrate the potential of Cr(VI) generation during jigging operation applied for ferrochrome recovery from slag.

  • Cited by: 74
  • Recovery of Chromium from Ferrochrome Slag

    2019-7-12  in the subsequent experimentation. Ferrochrome slag is treated with lime to conduct slag-lime solid-solid reaction. Chromium present in the slag reacts with lime to form mixed chromates. The reaction is conducted at 973K, soluble chromium ion was extracted with water and is subsequently separated by adsorbing fly ash based zeolite which can be recovered. The recovery of chromium metal in the slag

  • Author: Praphulla Ch, ra. M, HimaBindu. V. N. V., Krishna Chaitanya. M, Rajendra Prasad. P
  • Hexavalent Chromium Air Dispersion Modelling in the

    2010-1-5  terms of total elemental chromium, and no split between trivalent and hexavalent oxidation states was given. Table 1. US EPA emission factors for finishing operations and product handling. Emission Source Total Chromium (g/ton product) Treatment of molten alloy with chlorine or other gas in ladle 3 300 Casting of ferrochrome product 70

  • Potential Toxic Effects of Chromium, Chromite Mining

    2019-10-11  represent the number of bonds an atom is capable of making. Trivalent (Cr-III) and hexavalent (Cr-VI) are the most common chromium species found environmentally. Trivalent is the most stable form and its compounds are often insoluble in water. Hexavalent chromium is the second most stable form, and the most toxic. Many of its compounds are soluble.

  • An Insight into Microbial Remediation of Hexavalent ...

    2020-6-30  Chromium (Cr) is used by different industries like ferrochrome, electroplating, and tanning industries, because of its hardness, coloration, and anti-corrosive properties. Chromium exists in various oxidation states in the environment, out of which trivalent (Cr 3+ ) and hexavalent chromium (Cr 6+ ) are generally found in aqueous medium.

  • Cited by: 1
  • [PDF] Speciation of chromium in soils, plants and

    This study assessed chromium pollution in soils, plants, water and slag from a ferrochrome smelting plant in Gweru, Zimbabwe. Speciation of chromium in plant leaves, soil and slag samples was carried out by selective leaching of Cr (VI) using a sodium carbonate leaching procedure prior to the spectrophotometric determination of Cr (VI). Total Cr and Cr (III) concentration in the samples were ...

  • Transport and fate of hexavalent chromium in

    2019-3-28  The random disposal of Cr(VI) wastes on land-formed chromium-containing slag, and the rainfall subsequently causes their movement through the slag–soil system relentlessly (Zou et al. 2015). The chromium slag leachate results in soil contamination, and the accumulated Cr(VI) in soil can also engender acute and long-term toxic effects on soil ecosystems (Viti et al. 2006 ).

  • Cited by: 2
  • Exploring beneficial uses of ferrochrome slag: A case ...

    2021-2-17  ferrochrome slag: A case study of a South African Ferrochrome industry FF Mugivhi Orcid.org 0000-0003-3289-4056 ... Trivalent Chromium Cr(VI) Hexavalent chromium DEA Department of Environmental Affairs (now DEFF) DEFF Department of Environment, Forestry and Fisheries DWAF Department of Water Affairs and Forestry (now DWS) ...

  • Recovery of Chromium from Ferrochrome Slag

    2021-3-19  Ferrochrome slag may contain chromium in +3 and +6 oxidation states along with elemental chromium[5].Earlier studies reported the extraction of chromium ... An aliquot (10ml) of the (hexavalent chromium so formed) solution has been equilibrated with an equal volume of TOAO (0.01 M) in benzene pre equilibrated with appropriate concentration of ...

  • Hexavalent Chromium in the Recovery of

    2013-7-18  (1997). Hexavalent Chromium in the Recovery of Ferrochromium from Slag. Canadian Metallurgical Quarterly: Vol. 36, No. 4, pp. 261-268.

  • release behaviour of chromium from ferrochrome slag

    Release behaviour of chromium from ferrochrome slag. Huge amount of ferrochrome slag, a solid waste is being generated from submerged electric arc furnace during manufacturing of ferrochrome alloy. The waste slag contains about 6–12% chromium as chromium oxide and it has the potentiality of releasing hazardous chromium compounds.

  • Hexavalent Chromium Air Dispersion Modelling in the

    2010-1-5  result in mainly chromite emissions unlikely to contain significant amounts of hexavalent chromium. Pre-treatment processes such as drying, crushing and screening also produces chromium emissions, but mainly as trivalent chromium. The smelting of chromium is the major source of chromium emissions - open furnaces

  • Chromium Compounds - EPA

    2016-9-21  Chromium is a naturally occurring element in rocks, animals, plants, soil, and volcanic dust and gases. (1) Chromium occurs in the environment predominantly in one of two valence states: trivalent chromium (Cr III), which occurs naturally and is an essential nutrient, and hexavalent chromium (Cr VI), which, along with

  • Case Study: Chromite mining and processing

    hexavalent chromium.8 Sources of chromium emissions to air include coal and oil combustion (primarily trivalent), chrome plating (hexavalent) and industrial cooling towers (hexavalent).8 Chromium is removed from the atmosphere by fallout and precipitation over about 10 days.8 Smoking can contribute to chromium levels in indoor air as tobacco

  • Transport and fate of hexavalent chromium in

    2019-3-28  The transport and fate of hexavalent chromium Cr(VI) in slag–soil system, which remain poorly understood, are of great importance for environmental risk assessment and pollution control of Cr(VI) in soil and groundwater. Based on the migration behavior of Cr(VI) in the chromium-containing slag under the effects of rainfall, the transport and fate of Cr(VI) in soil were investigated.

  • [PDF] Speciation of chromium in soils, plants and

    This study assessed chromium pollution in soils, plants, water and slag from a ferrochrome smelting plant in Gweru, Zimbabwe. Speciation of chromium in plant leaves, soil and slag samples was carried out by selective leaching of Cr (VI) using a sodium carbonate leaching procedure prior to the spectrophotometric determination of Cr (VI). Total Cr and Cr (III) concentration in the samples were ...

  • Colorful Chromium ChemTalk

    2021-5-17  Trivalent chromium is a vital micronutrient and aids the efficiency of insulin in individuals who struggle with glucose intolerance. Hexavalent chromium or chromium is extremely toxic as it can cause cancer, destroy red blood cells, and give rise to genetic mutations. Electroplating with Chromium

  • Recovery of Chromium from Ferrochrome Slag

    2021-3-19  Ferrochrome slag may contain chromium in +3 and +6 oxidation states along with elemental chromium[5].Earlier studies reported the extraction of chromium ... An aliquot (10ml) of the (hexavalent chromium so formed) solution has been equilibrated with an equal volume of TOAO (0.01 M) in benzene pre equilibrated with appropriate concentration of ...

  • Exploring beneficial uses of ferrochrome slag: A case ...

    2021-2-17  ferrochrome slag: A case study of a South African Ferrochrome industry FF Mugivhi Orcid.org 0000-0003-3289-4056 ... Trivalent Chromium Cr(VI) Hexavalent chromium DEA Department of Environmental Affairs (now DEFF) DEFF Department of Environment, Forestry and Fisheries DWAF Department of Water Affairs and Forestry (now DWS) ...

  • Valuable waste - AT Minerals

    2018-10-19  toxic nature of trivalent and hexavalent chromium makes the flue dust from the ferrochrome industry hazardous. About 400-500 kg residue is generated per tonne of ferrochrome metal produced – this residue includes slag, flue dust and sludge [6]. Flue dust generation is increasing enormously as

  • Hexavalent Chromium in the Recovery of

    2013-7-18  (1997). Hexavalent Chromium in the Recovery of Ferrochromium from Slag. Canadian Metallurgical Quarterly: Vol. 36, No. 4, pp. 261-268.

  • Case Study: Chromite mining and processing

    hexavalent chromium.8 Sources of chromium emissions to air include coal and oil combustion (primarily trivalent), chrome plating (hexavalent) and industrial cooling towers (hexavalent).8 Chromium is removed from the atmosphere by fallout and precipitation over about 10 days.8 Smoking can contribute to chromium levels in indoor air as tobacco

  • A Functional Trivalent Chromium Process to Replace ...

    2019-10-8  thin layer of chromium (typically 0.003 to 2.5 µm, Altmayer, 1995) to provide a bright surface with wear and tarnish resistance when plated over a nickel layer. It is used for plating automotive trim/bumpers, bath fixtures and small appliances. Hexavalent chromium (Cr(VI)) plating has been commercialized for many years. However, a

  • Chromium adsorption and Cr(VI) reduction to trivalent ...

    Chromium as Cr(VI) is a industrially produced pollutant. Hexavalent chromium can be reduced to the trivalent state using various reductive agents or it can be removed from solution by surface-active adsorbents. In this study, both of these methods were evaluated using soya cake. A high efficiency fo

  • [PDF] Speciation of chromium in soils, plants and

    This study assessed chromium pollution in soils, plants, water and slag from a ferrochrome smelting plant in Gweru, Zimbabwe. Speciation of chromium in plant leaves, soil and slag samples was carried out by selective leaching of Cr (VI) using a sodium carbonate leaching procedure prior to the spectrophotometric determination of Cr (VI). Total Cr and Cr (III) concentration in the samples were ...

  • Trivalent Chromium Scientific.Net

    Abstract: The tannery industry generally produces trivalent chromium waste (Cr3 +) and hexavalent chromium (Cr6 +). This waste before being released into the environment must meet quality standards according to KEPMENLH no.51 / MENLH / 10/1995 concerning liquid quality standards for industrial activities which says the maximum total chromium content is 0.6 ppm.

  • Behavior of Hexavalent Chromium in a Polluted

    2019-5-26  This work describes the chemical mechanisms governing transport and reduction of hexavalent chromium in soils of a contaminated industrial waste landfill. Groundwater and soil analyses indicate that the main source of chromium is a slag heap essentially consisting of mill tailings. In the groundwater, downstream migration of Cr(IV) is limited thanks to a redox mechanism involving