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ferrochrome slag trivalent and hexavalent chromium

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. The Cr(VI) concentrations of water

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Hexavalent chromium removal by ferrochromium slag ...

2005-11-11  The chromium content in slags is 2–12%, in oxide and metal form. The slag/metal amount ratio in smelting varies from 1.0 to 1.8, depending on raw materials . Slag is discarded as a waste material in enormous quantities during the ferrochrome production. A relatively small percentage of this material finds application, but the vast majority of ...

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Hexavalent chromium removal by ferrochromium slag

Hexavalent chromium removal by ferrochromium slag ... Also, reduction of Cr(VI) to Cr(III) and a subsequent precipitation of Cr(III) by using ferrochrome slag (FS) in a model solution has been aimed. The effects of amount of acid, contact time, FS dosage, initial Cr(VI) concentration and temperature on the Cr(VI) reduction have been studied through the batch runs. The amount of acid has been ...

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Journal of Chemical and Pharmaceutical Research, 2013, 5(5 ...

Ferrochrome slag may contain chromium in +3 and +6 oxidation states along with elemental chromium[5].Earlier studies reported the extraction of chromium (VI) [6-8] as well as microbial activity of different metals[9]. The aim of the present investigation is to separate and estimate the chromium content (as chromium(VI) by oxidation) of the slag samples (Jindal Ferro Alloys Corpn., Kottha ...

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Figure 1 from In situ bioremediation of chromium (vi) in a ...

DOI: 10.3303/CET1761007 Corpus ID: 54586304. In situ bioremediation of chromium (vi) in a simulated ferrochrome slag @article{Bansal2017InSB, title={In situ bioremediation of chromium (vi) in a simulated ferrochrome slag}, author={Nikky Bansal and J. Coetzee and E. Chirwa}, journal={Chemical engineering transactions}, year={2017}, volume={61}, pages={55-60} }

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Determination of Trivalent and Hexavalent Chromium with ...

2011-11-21  trivalent chromium and hexavalent chromium must be measured and verified with mass balance (sum of both species equaling total chromium). This is necessary because dietary supplements report trivalent chromium, an essential trace element, as an ingredient, but hexavalent chromium, a toxic carcinogen, may also be present. Because trivalent chromium is stable in acidic conditions and hexavalent ...

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Case Study: Chromite mining and processing

Hexavalent chromium is the form of chromium most hazardous for human health, and is largely produced by human activities.1,2,6 Chromium (VI) is generally more readily absorbed than chromium (III), but the rates depend on the a An Adequate Intake is determined when there is insufficient evidence to establish a Recommended Dietary Allowance, which is the average daily intake that meets a ...

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Chromium Compounds - US EPA

Hazard Summary Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (Cr VI).   Exposure may occur from natural or industrial sources of chromium. Chromium III is much less toxic than chromium (VI).

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Toxicological Review of Trivalent Chromium (CAS No. 16065 ...

(trivalent chromium), and +6 (hexavelent chromium) valence states. In the +3 valence state, the chemistry of chromium is dominated by the formation of stable complexes with both organic and inorganic ligands (Hartford, 1979). In the +6 valence state, chromium exists as oxo species such as CrO3 and CrO4 2-that are strongly oxidizing (Cotton and Wilkinson, 1980). Chromium in the ambient

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Deadly Hexavalent Chromium in Soil - Waste Advantage Magazine

2014-09-03  Chromium Treatment: Hexavalent Chromium to Trivalent Chromium Test Results. Overview. Samples of Hexavalent Chromium were treated to convert Hexavalent Chromium to Trivalent Chromium. The basis for the treatment is outlined below: The soil and rocks were crushed through a shredder and mixed together to make a homogeneous sample. After doing several

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Hexavalent chromium removal by ferrochromium slag ...

2005-11-11  The ferrochromium slags consist mainly of SiO 2, Al 2 O 3 and MgO in different phases such as spinel, MgOAl 2 O 3, and forsterite, MgOSiO 2, but also smaller amounts of CaO, chromium and iron oxides and metal fragments. The chromium content in slags is 2–12%, in oxide and metal form.

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(PDF) Hexavalent chromium removal by ferrochromium slag

There is an in situ generation of ferrous sulphate by the effect of oxidizing agent and iron content of ferrochrome slag which is capable of reducing Cr(VI) to trivalent chromium. Water samples ...

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Journal of Chemical and Pharmaceutical Research, 2013, 5(5 ...

Ferrochrome slag may contain chromium in +3 and +6 oxidation states along with elemental chromium[5].Earlier studies reported the extraction of chromium (VI) [6-8] as well as microbial activity of different metals[9]. The aim of the present investigation is to separate and estimate the chromium content (as chromium(VI) by oxidation) of the slag samples (Jindal Ferro Alloys Corpn., Kottha ...

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Journal of Cleaner Production - University of Oulu

Hexavalent chrome Cr(VI) Chromite Ferrochrome Ring of Fire Canada abstract During stainless steel production, new chromium units are obtained from ferrochrome, a relatively crude alloy produced from chromite ore. Large chromite reserves have recently been discovered in the so-called Ring of Fire, Canada. Due to the strategic importance of uninterrupted stainless steel production in North ...

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Hexavalent Chromium Is Carcinogenic to F344/N Rats and ...

2009-05-01  Hexavalent chromium [Cr ... (VI) in drinking water or in soil or slag fill concluded that these studies did not provide definitive evidence of an increase in cancer incidence or mortality rates (Proctor et al. 2002). However, a retrospective mortality study in China found higher incidences of lung and stomach neoplasms in people living near a chromium smelting plant compared with the general ...

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Toxicological Review of Trivalent Chromium (CAS No. 16065 ...

(trivalent chromium), and +6 (hexavelent chromium) valence states. In the +3 valence state, the chemistry of chromium is dominated by the formation of stable complexes with both organic and inorganic ligands (Hartford, 1979). In the +6 valence state, chromium exists as oxo species such as CrO3 and CrO4 2-that are strongly oxidizing (Cotton and Wilkinson, 1980). Chromium in the ambient

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The Letter The Sault Star Didn’t Want To Publish ...

Sault Ste Marie desperately needs the jobs that the proposed Noront Resources ferrochrome production facility would bring but we need to be vigilant that this does not come at the expense of the health of our people and our environment. Hexavalent chromium (chromium-6) is the inevitable byproduct of chromium manufacturing. It is a known genotoxic carcinogen, potentially causing cancers of the ...

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Chromite critics warn element 'very toxic' Sudbury Star

2018-03-04  "Breathing in (trivalent and hexavalent) chromium can irritate the nose, throat and lungs and produce inflammation. Cr-VI inhalation during chromium industrial work is known to cause nosebleeds, ulcers and holes in the septum (structure between your nostrils), asthma, lung cancer, sinonasal cancer and possibly other cancers. Breathing Cr-VI seems to be the most dangerous route

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Not everyone in Sudbury is enamoured with smelters ...

2018-02-08  Mayor Bigger had talked about the slag and using it for roads if that slag is crushed it releases the chromium hexavalent." According to the Occupational Safety and Health Administration, breathing small amounts of hexavalent chromium, even for long time periods, does not cause respiratory tract irritation in most people.

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Smelter won't go where it's not wanted: Noront - Northern ...

2017-12-06  Groups like MiningWatch and Public Health Ontario have raised concerns about the toxic impact on human and animal health exposure from exposure to chromium mining and processing. The Hollywood film Erin Brockovich portrayed the health problems associated with the dumping of hexavalent chromium (chromium-6) into the groundwater of a small California town.

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(PDF) Hexavalent chromium removal by ferrochromium slag

There is an in situ generation of ferrous sulphate by the effect of oxidizing agent and iron content of ferrochrome slag which is capable of reducing Cr(VI) to trivalent chromium. Water samples ...

More

Journal of Cleaner Production - University of Oulu

Hexavalent chrome Cr(VI) Chromite Ferrochrome Ring of Fire Canada abstract During stainless steel production, new chromium units are obtained from ferrochrome, a relatively crude alloy produced from chromite ore. Large chromite reserves have recently been discovered in the so-called Ring of Fire, Canada. Due to the strategic importance of uninterrupted stainless steel production in North ...

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Chromite - Wikipedia

When chromium is in the trivalent (Cr(III)) form, it is a crucial part of a balanced animal and human diet. However, its defect will cause a disruption to the lipids and glucose metabolism in animals and humans. On the other hand, when chromium is in its hexavalent (Cr(VI)) form, it is a highly toxic carcinogen and if ingested by an animal or human it may cause death. Health effects. When ...

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Conversion of Chromium Ore Processing Residue to Chrome Steel

Trivalent chromium in chromite ore was oxidized to hexavalent chromium. The highly soluble hexavalent chromium was then removed from the COPR (left over Chromium Ore Processing Residue) leaving un-oxidized trivalent chromium and slow-dissolving hexavalent chromium compounds [Burke et al., 1991]. In the absence of information on the toxicity of hexavalent chromium, COPR was

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Chromite critics warn element 'very toxic' Sudbury Star

2018-03-04  "Breathing in (trivalent and hexavalent) chromium can irritate the nose, throat and lungs and produce inflammation. Cr-VI inhalation during chromium industrial work is known to cause nosebleeds, ulcers and holes in the septum (structure between your nostrils), asthma, lung cancer, sinonasal cancer and possibly other cancers. Breathing Cr-VI seems to be the most dangerous route

More

Hexavalent Chromium Is Carcinogenic to F344/N Rats and ...

2009-05-01  Hexavalent chromium [Cr ... (VI) in drinking water or in soil or slag fill concluded that these studies did not provide definitive evidence of an increase in cancer incidence or mortality rates (Proctor et al. 2002). However, a retrospective mortality study in China found higher incidences of lung and stomach neoplasms in people living near a chromium smelting plant compared with the general ...

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3 ELECTROLYTIC CHROMIUM-METAL PRODUCTION High-Purity ...

In general, chromium-containing solutions that exit the process stream are mixed with the main process stream at the ferrochrome leaching stage, a practice driven largely by the cost of chromium units. These solutions include mother liquors from ferrous ammonium sulfate recrystallization and anolyte containing chromium (VI) from the electrolytic process, reduced to the chromium (III) state ...

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Not everyone in Sudbury is enamoured with smelters ...

2018-02-08  Mayor Bigger had talked about the slag and using it for roads if that slag is crushed it releases the chromium hexavalent." According to the Occupational Safety and Health Administration, breathing small amounts of hexavalent chromium, even for long time periods, does not cause respiratory tract irritation in most people.

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'Them plants are killing us': inside a cross-border battle ...

2020-04-07  Hexavalent chromium, or chromium-6, is a chemical made infamous by the film Erin Brockovich, which tells the true story of how Pacific Gas Electric contaminated drinking water with chromium-6 in the town of Hinkley, Calif., causing people to develop cancer. The International Agency for Research on Cancer has classified it as carcinogenic to humans, and studies have shown that

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Smelter won't go where it's not wanted: Noront - Northern ...

2017-12-06  Groups like MiningWatch and Public Health Ontario have raised concerns about the toxic impact on human and animal health exposure from exposure to chromium mining and processing. The Hollywood film Erin Brockovich portrayed the health problems associated with the dumping of hexavalent chromium (chromium-6) into the groundwater of a small California town.

More

(PDF) Hexavalent chromium removal by ferrochromium slag

There is an in situ generation of ferrous sulphate by the effect of oxidizing agent and iron content of ferrochrome slag which is capable of reducing Cr(VI) to trivalent chromium. Water samples ...

More

Ferrochrome Smelting Test Work on Ring of Fire Chromite ...

The outcomes of this test work will (1) provide dust, ferrochrome and slag samples for use in advanced characterization studies aiming to determine the sources and conditions promoting the formation of hexavalent chromium, and to optimize furnace and operational conditions improving the quality of slag to make it inert, and (2) serve the broader needs of NRCan’s Chromite Project in ...

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Journal of Cleaner Production - University of Oulu

Hexavalent chrome Cr(VI) Chromite Ferrochrome Ring of Fire Canada abstract During stainless steel production, new chromium units are obtained from ferrochrome, a relatively crude alloy produced from chromite ore. Large chromite reserves have recently been discovered in the so-called Ring of Fire, Canada. Due to the strategic importance of uninterrupted stainless steel production in North ...

More

Hexavalent Chromium Is Carcinogenic to F344/N Rats and ...

2009-05-01  Hexavalent chromium [Cr ... (VI) in drinking water or in soil or slag fill concluded that these studies did not provide definitive evidence of an increase in cancer incidence or mortality rates (Proctor et al. 2002). However, a retrospective mortality study in China found higher incidences of lung and stomach neoplasms in people living near a chromium smelting plant compared with the general ...

More

1988 OSHA PEL Project - Chromium Metal NIOSH CDC

The Agency finds that the metallic form of chromium, ... which may be associated with exposure to metallic chromium is the frequent co-existence of the metallic form with both trivalent and hexavalent salts (Tr. p. 11-136). The Princi et al. study (1962, as cited in ACGIH 1986/Ex. 1-3, p. 139) reflects the problem of confounding exposures to which the AISI alludes. In this study, ferrochrome ...

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Not everyone in Sudbury is enamoured with smelters ...

2018-02-08  Mayor Bigger had talked about the slag and using it for roads if that slag is crushed it releases the chromium hexavalent." According to the Occupational Safety and Health Administration, breathing small amounts of hexavalent chromium, even for long time periods, does not cause respiratory tract irritation in most people.

More

Hexavalent Chromium - Overview Occupational Safety and ...

Hexavalent chromium [Cr(VI)] is one of the valence states (+6) of the element chromium. It is usually produced by an industrial process. Cr(VI) is known to cause cancer. In addition, it targets the respiratory system, kidneys, liver, skin and eyes. Chromium metal is added to alloy steel to increase hardenability and corrosion resistance. A major source of worker exposure to Cr(VI) occurs ...

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Chromite (Cr2FeO4) CrFeO4 - PubChem

Chromite ore processing residue (COPR) containing measurable levels of hexavalent and trivalent chromium. [Cr(VI) and Cr(III), respectively] has been used to fill in low-lying areas in Hudson County, N.J. While it has been demonstrated that direct dermal contact with solutions containing Cr(VI) may elicit allergic contact dermatitis (ACD) in previously sensitized individuals, it is unknown to ...

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Open Letter From Doctors On Ferrochrome Smelter ...

Much of chromium VI waste is contained in slag ponds (4); there are no data on how safe such ponds would be in Sault Ste. Marie’s unique climate. Many of the health risks of chromium VI show links to airborne contamination (4, 7, 8, 9). 7. Noront has released details of the proposed smelter for Sault Ste. Marie stating that the basis for the design will be the ferrochrome smelter in Tornio ...

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