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Even though groundwater can be a safe and reliable source of drinking water, it can also be affected by geogenic contaminants, such as arsenic, iron and manganese. Therefore, increased consumption of groundwater in some area has led to long-term exposures to arsenic 4, iron 5 and manganese 6, 7 that are associated with …
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products of the roasting of arsenic-bearing ore minerals or coal. Condensation of combustion vapors makes "white arsenic" powder characteristic of arsenic trioxide (National Research Council 1977). The arsenolite structure is some-what unusual, consisting of [As 4O 6] cages linked by bridg-ing oxygen atoms (FIG. 2). Arsenic trioxides are ...
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The experimental results revealed that the arsenic in arsenopyrite-bearing iron ore can be removed in the form of As2O3 (g) in an air or nitrogen atmosphere by a roasting method. The...
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Inorganic arsenicals have been used in agriculture as pesticides or defoliants for many years and, in localized areas, oxides of arsenic have contaminated soils as a result of fallout from ore-smelting operations and coal-fired power plants. Use of inorganic arsenicals is no longer permitted in most agricultural operations, and recent air pollution controls have markedly …
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Leaching of High-Grade Ore. The effects of NaOH concentration, oxygen pressure, temperature, reaction time, and percent solids on extraction of arsenic from ore A are given in table 4. The ore contains 61 pct arsenopyrite, and the stoichiometric NaOH for complete extraction of arsenic is 1.88 mol of NaOH per 100 g ore according to equation 1.
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ore (15). Alkaline pressure oxidation yields a residue composed primarily of iron oxide, which is environmentally safe and compatible with the cyanidation process. Solu bilized arsenic and sulfur are recovered as relatively pure compounds and can be a source of raw material for insec
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arsenopyrite, an iron sulfoarsenide mineral (FeAsS), the most common ore of arsenic.It is most commonly found in ore veins that were formed at high temperatures, as at Mapimí, Mex.; Butte, Mont.; and Tunaberg, Swed. Arsenopyrite forms monoclinic or triclinic crystals with an orthorhombic shape; the physical appearance of these crystals is seldom an …
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Arsenic-containing iron-ore fines in this area can produce mobile colloids through coagulation and flocculation in natural waters contacting the soils (Pandey et al., 2004). The mobile colloids can be easily transported to other areas and can create secondary arsenic-contamination sites. Thus, a rapid and effective remediation is …
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The study investigates the ability to remove copper, tin and arsenic from iron ore, scrap and liquid steel based on the literature and thermodynamic calculations using the FactSage 7.2 software.
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Arsenic is a gray metal rarely encountered as a free element, but is widely distributed in minerals and ores that contain copper, iron and lead. Arsenic is often found in groundwater as a result of the natural …
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The arsenic-bearing iron ore was sourced from Yunnan Province. Samples for chemical analysis were collected through a process of multi-point sampling and …
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Arsenopyrite is a hard metallic iron arsenic sulfide with steel gray to silver-white color, and the major source of arsenic. The mineral in purest form contains 46.0% As, 34.3% Fe, and 19.7% S, which turns it chemically toxic. The mineral is associated with sulfide orebodies and gold deposits. Arsenopyrite is the major source of arsenic ...
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1.4. Environmental occurrence. Arsenic is the 20 th most common element in the earth's crust, and is emitted to the environment as a result of volcanic activity and industrial activities. Mining, smelting of non-ferrous metals and burning of fossil fuels are the major anthropogenic sources of arsenic contamination of air, water, and soil (primarily in the …
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Since the presence of arsenic in iron ore lumps is related to the presence of iron, it is assumed that the highest concentrations of arsenic is in the brown-coloured …
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e.g. the use of ferric reagents to precipitate and absorb dissolved arsenic species into disposable iron compounds. [14] Aqueous arsenic species can also be filtered from waste and tailings with a variety of adsorbents, including iron oxides, clay liners, and activated charcoal filters, which can be disposed of safely. [14] The use of plants ...
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Arsenic is widespread in the environment where it occurs combined with metals and sulfur and as secondary minerals in combination with oxygen. Its atomic structure allows it to be trivalent or pentavalent, and its properties lead to its classification as a metalloid in the periodic classification of the elements. Arsenic trioxide is a by-product …
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The mechanism of arsenic removal during a sintering process was investigated through experiments with a sintering pot and arsenic-bearing iron ore containing arsenopyrite; the corresponding chemical properties of the sinter were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES), X …
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This study investigated groundwater pollution and potential human health risks from arsenic, iron, and manganese in the rural area of Jashore, Bangladesh. Study results show that the mean value of groundwater pH is 7.25 ± 0.31, with a mean conductivity of 633.94 ± 327.41 μs/cm, while about 73, 97, and 91% of groundwater samples exceeded …
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As part of our ongoing research on the application of elemental geochemistry methods to Early Precambrian ferrous quartzite formations and in order to elucidate the nature of their ore material, we investigated the distribution of As, Sb, and Bi in exogenic oxide-hydroxide iron ores, sedimentary carbonate rocks and iron ores, and ferro …
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Keywords: iron–arsenic alloys; solidification; microstructure; segregation; eutectic 1. Introduction Arsenic is one of the common residual elements in steel and mainly comes from iron ore, scrap steel, ferroalloy, and other furnace charge [1]. With the recycling of scrap steel and the utilization of iron ore containing arsenic, the detri-
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Galena is the principle ore of lead, and forms glistening silver cubes with almost unnaturally perfect shapes. ... Arsenopyrite is arsenic iron sulfide, which is the same type of mineral as pyrite (fool's gold, iron sulfide), but with a heavy addition of arsenic. If one attempts to heat or in any way alter the mineral, a strong garlic odor of ...
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Arsenic content in iron ore can be as high as 0.5 wt% [ 4 ]. If ores with As are directly charged into the blast furnace, As readily dissolves into the molten iron. …
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Although the distribution of naturally occurring arsenic contamination around ore bodies is generally localized, anthropogenic materials associated with the mining of ore bodies, such as tailings and sludge, expand the area of contamination into the hydrosphere and pedosphere of the surrounding area. ... Instead, arsenic-bearing iron hydroxides ...
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Iron is the heaviest element formed in the cores of stars, according to JPL. Elements heavier than iron can only be created when high mass stars explode (supernovae). The Latin name for iron is ...
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After column bio-oxidation for 90 days, the weight loss amount of the gold ore was 24 ± 2%. The contents of various elements and the oxidation extent of arsenic, iron and sulfur are shown in Table 2. The data showed that oxidation extent of arsenic, iron and sulfur are 57 ± 1%, 38 ± 1% and 44 ± 1%, respectively.
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The addition of 0.2 g ZVI clearly decreased arsenic release, and the addition of 4.0 g ZVI led to the lowest arsenic release among all tests. The decrease of arsenic released from the tailings was due to the adsorption and uptake of arsenic by secondary iron-containing minerals and Fe–As(V) secondary mineralisation.
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The optimum procedure results in a high-grade iron concentrate with an iron assay of 65.65%, an Fe recovery rate of 80.07%, and an arsenic content of 0.085%, while achieving a 93.29% As removal ...
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1. Introduction. Arsenic is a toxic and ubiquitous element found in all compartments of the environment and can be responsible for severe health problems (Smith et al., 2006).Epidemiological studies conducted in Chile and South-East Asia have demonstrated its chronic toxicity via long-term ingestion of contaminated water (Meharg …
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Extracting iron while minimizing the health and environmental risks associated with arsenic contamination necessitates the removal of arsenic from arsenic-bearing iron ores to ensure a safe and sustainable supply of this metal for industries. The beneficiation ...
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The arsenic content in the iron ore concentrate and scrap steel used by the steelworks was 30 mg/kg and 220 mg/kg, respectively, which were considered low levels of arsenic content for raw materials. The arsenic content in higher-quality iron ore ranged from 25 mg/kg to 30 mg/kg (Fang and Liu, 2015).
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