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Showing 1 to 20 of 281 for “"pyrite"”.
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The ferric leaching of pyrite
The bioleaching of pyrite has been found to occur via an indirect mechanism. Ferric iron leaches the pyrite, and is reduced to ferrous iron. Bacteria such as Thiobacillus ferrooxidans oxidise the ferrous iron to ferric iron, thus maintaining a high redox potential. In this thesis, the effect of the …
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Electrochemical studies of pyrite and galena
… to investigate the initial oxidation behavior of pyrite in order to better understand how mine wastes containing pyrite generate acid water. It was found that a unique potential exists at which a fresh surface of pyrite undergoes neither oxidation nor reduction. This potential is pH dependent and …
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Quantitative determination of pyrite by Mossbauer spectroscopy
Includes bibliographical references (pages 55-56).
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The flotation of pyrite using xanthate collecters
The flotation properties of pyrite were found to be significantly influenced by variations in the pH. In acidic solutions the pyrite floatability is very high, and recoveries of 95% could be achieved using only a frother. A sharp decrease in floatability was observed in alkaline solutions, possibly …
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Thermodynamic studies of xanthate adsorption on pyrite
… changes, for the adsorption of xanthates on pyrite. The electrochemical technique is based on the measurement of the open-circuit potentials of a pyrite electrode immersed in xanthate solutions at various temperatures. The thermochemical technique involves the determination of the heats of …
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The oxidation of pyrite and its environmental consequences
Summary available: p. [i].
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Differential flotation of low grade gold pyrite ores
Includes bibliographical references.
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Biooxidation of a gold bearing arsenopyrite/pyrite concentrate
… characterise the biooxidation of an auriferous pyrite/arsenopyrite flotation concentrate, and to interpret laboratory batch and continuous pilot plant data in the light of the logistic model. Furthermore, the possibility of predicting continuous biooxidation plant performance from batch data was …
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The effect of electrolytes on the flotation of pyrite
In the flotation of pyrite a minimum concentration of any ions is necessary to stabilize the froth and thus produce a reasonable recovery of pyrite. In the absence of ions a "dry froth" is formed which results in a decreased mass pull and thus a low pyrite recovery. The predominant effect of an …
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A Study of Triboelectrification for Coal , Quartz and Pyrite
… mechanisms of coal, quartz, and pyrite were investigated in an in-line static mixer charger. A new in-situ charge-measuring device has been developed, in which an in-line mixer charger is located in side a Faraday cage. This makes it possible to observe the charging mechanisms of …
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Control of Surface Chemistry of Gold, Pyrite and Pyrrhotite
Removing pyrite from coal and pyrrhotite from pentlandite play a critical role in coal and nickel production, respectively, to meet the stringent restriction on SO2 emission. The present project investigates first the mechanism of xanthate adsorption on gold using Atomic Force Microscope (AFM), …
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Pyrite porphyroblast paragenesis at the Cherokee Mine, Ducktown, Tennessee
Pyrite porphyroblasts up to 300 mm in size are common in the polymetamorphosed, iron-rich, stratabound, massive sulfide ore at the Cherokee Mine, Ducktown, Tennessee. These porphyroblasts contain abundant inclusions of sphalerite, calcite, and micas that are used to determine the paragenesis of the …
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Electrochemical Studies of Copper-Activation of Sphalerite and Pyrite
Carbon matrix composite (CMC) electrode and surface conducting (SC) electrode have been developed to study the copper-activation and the subsequent xanthate adsorption on insulating sphalerite. Fabricating CMC electrode involves embedding sphalerite particles in carbon to form a carbon matrix …
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The kinetics of ferrous iron oxidation by Leptospirillum-like bacteria in absence and in presence of pyrite and pyrite/arsenopyrite mixtures in continous and batch cultures
The leaching process of pyrite and pyrite/arsenopyrite in presence of bacteria is considered a 2-step mechanism, in which i) the mineral sulphide is chemically leached by ferric iron into the metal ion and sulphate and ii) the bacteria regenerate ferric iron. The kinetic parameters of these …
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Pyrite geochemistry across the Betze-Post deposit, northern Carlin Trend, Nevada
… ore stage fluid flow. For example, ore stage pyrites occur within brecciated rocks and small-scale fractures within the Wispy Member of the Popovich Formation. Ore stage pyrites have trace element signatures that suggest that the fluid was evolving both temporally and spatially. The associated …
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Synergistic effects between thiol collectors used in the flotation of pyrite
… of these collectors is used in the flotation of pyrite at pH =4 and, secondly, why synergistic effects are observed, if any. The focus of the investigation was a 90:10 mole ratio mixture of PNBX and cyclohexyl DTC, although other collector ratios were compared in the batch flotation tests. This …
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Bacterial and chemical depression of pyrite in froth flotation of coal
Froth flotation was used to separate the pyrite sulfur and ash from pulverized coal samples of Illinois No. 6, Pittsburgh, and Middle Kittanning seams. In order to depress the coal pyrite in the flotation process, the coal samples were conditioned in "bacterial liquor." Iron oxidizing bacteria …
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Depression of pyrite in polymetallic sulfide flotation using chitosan-grafted-polyacrylamide polymers
… for the first time, as selective depressants of pyrite in the flotation of base metal sulfides. Fundamental studies of the adsorption behavior of Chi-g-PAM on model sulfide minerals indicated that Chi-g-PAM was more selective to pyrite’s surfaces as compared to base metal sulfides. Results …
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