Skocz do pozycji: 1.

Tytuł:

Effect of pyrite type on the electrochemistry of chalcopyrite/pyrite interactions

Autorzy:

Forbes, E.
Smith, L.
Vepsalainen, M.

Powiązania:

https://bibliotekanauki.pl/articles/110218.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

flotation
arsenic
pyrite
galvanic interaction
Surface oxidation

Opis:

Pyrite is the most common sulphide gangue mineral occurring in base metal sulphide ores around the world. Pyrite is known to galvanically interact with valuable minerals such as chalcopyrite, altering their electrochemical and flotation behaviour. Different types of pyrite are known to vary in texture, chemical composition and electrochemical activity. However, the effect that these differences have on the degree of pyrite interaction with chalcopyrite are not well studied. This work examines two distinct types of pyrite from different deposits that have a similar chemical composition, but vary greatly in texture. It investigates the way in which these pyrites interact with chalcopyrite surfaces, affecting both its electrochemical behaviour and floatability. It was found that the Renison pyrite was characterised by a much higher level of surface activity than the Huanzala pyrite. This was attributed to the elevated levels of arsenic within the mineral’s crystalline matrix.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 4; 1117-1129
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:

Mechanism and kinetics of pyrite transformation at elevated temperatures

Autorzy:

Aracena, Alvaro
Jerez, Oscar

Powiązania:

https://bibliotekanauki.pl/articles/2146885.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
pyrrhotite
roasting
kinetics

Opis:

Pyrite (FeS2) is known as a sulfide that provides energy for various pyrometallurgical processes (fusion and conversion). There are several studies related to the evaluation of pyrite oxidation mechanisms at high temperatures, obtaining discrepancies in the products generated. In our work, the novelty of our research would be to obtain the thermochemical oxidation mechanism of FeS2 by using conventional thermogravimetric methods. The oxidative roasting of pyrite from 550 to 800°C was analyzed for an oxygen concentration of 5.07 to 28.06 kPa of oxygen and particle size between 12.3 to 33.8 microns. The results showed that the pyrite proceeded by sequential roasting: first, it produced an intermediate compound, pyrrhotite (Fe7S8), which was later oxidized to generate hematite (Fe2O3), both stages validated by weight loss of the sample as well as by analysis by DRX. Each stage had a different roasting speed as it was also influenced differently by different parameters. The temperature and particle size favored the rate of pyrrhotite generation, and the oxygen concentration favored the rate of hematite formation. The first-order kinetic equation ln (1-XPy) represented the roasting of the first stage (FeS2 → Fe7S8), with a calculated activation energy of 70.1 kJ/mol. The order of reaction was 0.5 concerning the partial pressure of oxygen and inversely proportional to the initial particle radius.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 6; 127--139
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 3.

Tytuł:

Chlorinated benzenes and benzene degradation in aerobic pyrite suspension

Autorzy:

Pham, Hoa Thi
Chihiro, Inoue

Powiązania:

https://bibliotekanauki.pl/articles/205353.pdf

Data publikacji:

2019

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

benzene
degradation
pyrite
aerobic
chlorinated benzene

Opis:

The focus of this study is to investigate the applicability of natural mineral iron disulfide (pyrite) in degradation of aromatic compounds including benzene and several chlorinated benzenes (from mono-chlorinated benzene (CB), di-chlorinated benzenes (di-CBs) to tri-chlorobenzenes (tri-CBs) in aerobic pyrite suspension by using laboratory batch experiments at 25°C and room pressure. At first, chlorobenzene was studied as a model compound for all considered aromatic compounds. CB was degraded in aerobic pyrite suspension, transformed to several organic acids and finally to CO₂ and Clˉ. Transformations of remaining aromatic compounds were pursued by measuring their degradation rates and CO₂ and Clˉ released with time. Transformation kinetics was fitted to the pseudo-first-order reactions to calculate degradation rate constant of each compound. Degradation rates of the aromatic compounds were different depending on their chemical structures, specifically the number and position of chlorine substituents on the benzene ring in this study. Compounds with the highest number of chlorine substituent at m-positions have highest degradation rate (1,3,5-triCB > 1,3-diCB > others). Three chlorine substituents closed together (1,2,3-triCB) generated steric hindrance effects. Therefore 1,2,3-triCB was the least degraded compound The degradation rates of all compounds were in the following order: 1,3,5-triCB > 1,3-diCB > 1,2,4-triCB ≅1,2-diCB ≅CB ≅benzene > 1,4-diCB > 1,2,3-triCB. The final products of the transformations were CO₂ and Clˉ. Oxygen was the common oxidant for pyrite and aromatic compounds. The presence of aromatic compounds reduced the oxidation rate of pyrite, which reduced the amount of ferrous and sulfate ions release to aqueous solution.

Źródło:

Archives of Environmental Protection; 2019, 45, 1; 115-125
2083-4772
2083-4810

Pojawia się w:

Archives of Environmental Protection

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 4.

Tytuł:

The influence of cyanide salts and ferrous sulphate on pyrite flotation

Autorzy:

Kostovic, M.
Vucinic, D.

Powiązania:

https://bibliotekanauki.pl/articles/110668.pdf

Data publikacji:

2016

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
flotation
ferrous sulphate
cyanide salts
depression

Opis:

The effect of cyanide salts as depressants, i.e. sodium cyanide (NaCN) and complex cyanide salts such as potassium ferricyanide (K3Fe(CN)6) and potassium ferrocyanide (K4Fe(CN)6), as well as combination of sodium cyanide with ferrous sulphate (FeSO4/NaCN) on pyrite flotation was investigated. Tests covered the frothless flotation of pyrite under different concentrations of depressants at various solution pH’s with potassium butyl xanthate (KBX) as collector. Flotation test results have shown that NaCN, and even more the combination of reagents FeSO4/NaCN are more successful in pyrite depression than complex cyanide salts, such as K3Fe(CN)6 and K4Fe(CN)6. Surface characteristics of pyrite were studied using rest potential (Eh) measurements and infrared attenuated total reflection spectroscopy (ATR-IR). In the presence of tested reagents in the flotation system, iron cyanide compounds and hydrated iron oxides were formed on pyrite surface. The composition of formed compounds depends not only on cyanide ions in the solution, but also on the pH of the system and solution species. These compounds, depending on the reagents used, are responsible for the resulting efficiency of the pyrite depression.

Źródło:

Physicochemical Problems of Mineral Processing; 2016, 52, 2; 609-619
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:

Flotation separation influenced by the rheological properties of diaspore-pyrite mixed pulp

Autorzy:

Zhao, Yongqing
Li, Xianhai

Powiązania:

https://bibliotekanauki.pl/articles/27323666.pdf

Data publikacji:

2023

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

bauxite
diaspore
pyrite
flotation
rheological property
viscosity

Opis:

The effects of pyrite and diaspore with different particle sizes on the rheological properties of pulp with butyl xanthate added as a collector were studied, and the mechanism for rheological pyrite separation from diaspore by flotation was probed. The apparent viscosity of the diaspore pulp with different particle sizes was higher than that of pyrite, especially for -30 μm diaspore. Microfine diaspore was an important component affecting the apparent viscosity and yield stress of the diaspore-pyrite mixed pulp, and the pulp became a non-Newtonian fluid when the mass fraction of fine-grained diaspore in the mixed pulp was high. In this study, sodium hexametaphosphate (SHMP) was used to control the rheology of the mixed pulp and improve the pyrite flotation, and the S (sulfur) recovery rate first increased and then decreased with increasing SHMP concentration. The apparent viscosity of the pulp decreased by 3.01% and the S recovery rate increased by 34.83% when the amount of added SHMP was 0.05 mg/kg. The apparent viscosity with 0.50 mg/kg SHMP was 21.76% lower than that seen with the addition of 0.05 mg/kg SHMP, but the S recovery rate was also reduced by 14.94%. Further research showed that the increased SHMP concentration led to increases in the electronegativities of the particle surface and the repulsive force between particles, which prevented agglomeration of the particles, reduced the apparent viscosity and yield stress of the mixed pulp, promoted collisions between the pyrite particles and the bubbles, and reduced the resistance of the air bubbles to flotation.

Źródło:

Physicochemical Problems of Mineral Processing; 2023, 59, 6; art. no. 174305
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 6.

Tytuł:

Comparison of anionic, cationic and amphoteric collectors used in pyrite flotation

Autorzy:

Bulut, Gülay
Sirkeci, A. A.
Arı, Beril

Powiązania:

https://bibliotekanauki.pl/articles/1446764.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

flotation
pyrite
amine
collectors
xanthate

Opis:

In this study, flotation tests were conducted with purified pyrite and ore samples. The collectors employed were anionic and cationic type such as potassium ethlyl-amyl xanthate, Tomamine M73 and Resanol Bal. According to the flotation tests, it was found that pyrite floated at low pH and depressed at high pH values with xanthates. On the other hand, in the case of cationic collectors which are Tomamine M73 (alkyl ether amine, an amphoteric surfactant) and Resanol Bal (N-3-tridecyloxy propyl 1-3 diamine, branched acetate) pyrite floated at high pH values. It was shown that amine type collectors could be efficient to selectively float pyrite from chalcopyrite at alkali pH ranges in the case of ore samples.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 5; 15-22
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 7.

Tytuł:

Pyrite flotation in the presence of galena. Study on galvanic interaction

Autorzy:

Allahkarami, E.
Poor, A. Z.
Rezai, B.

Powiązania:

https://bibliotekanauki.pl/articles/110735.pdf

Data publikacji:

2017

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

flotation
galena
pyrite
galvanic interactions

Opis:

In this investigation, galvanic interaction between galena and pyrite in flotation and its effect on floatability of pyrite were studied. Rest and mixed potential studies in the presence and absence of a collector indicated that pyrite was nobler than galena under all investigated conditions. Therefore, pyrite served as a cathode in galvanic interactions with galena. Floatability of pyrite was performed alone and as a mixture with galena in the ratios of pyrite to galena equal to 1:4, 1:1 and 4:1. The experiments were conducted with air and nitrogen. In any galvanic contact between pyrite and galena, anodic oxidation occurred on the galena surface, and hydrolysed lead species adsorbed on the pyrite surface. The investigation of the various reactions occurring on the sample surface was investigated by ethylene diamine-tetra acetic acid disodium salt (EDTA) extraction and X-ray photoelectron spectroscopy (XPS) measurements. In the presence of nitrogen, floatability of pyrite increased. The recovery of pyrite in the presence of air was 22%, while in the mixture with galena (ratio 1:4) the recovery increased to 43%. The results indicated that the presence of galena improved floatability of pyrite.

Źródło:

Physicochemical Problems of Mineral Processing; 2017, 53, 2; 846-858
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 8.

Tytuł:

Adsorption mechanism of copper xanthate on pyrite surfaces

Autorzy:

Deng, Zhengbin
Cheng, Wanli
Tang, Yun
Tong, Xiong
Liu, Zhihong

Powiązania:

https://bibliotekanauki.pl/articles/1447276.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
cupric xanthate
cuprous xanthate
adsorption
surface

Opis:

The ratio of the hydrophobic to hydrophilic species and their distribution on mineral surfaces significantly influences the floatability of sulfide minerals. Through the flotation test, the influence of different reagents on pyrite flotation was examined. The interaction mechanisms between copper xanthate and pyrite were evaluated using advanced analysis technologies, including contact angle measurements, zeta potential analysis, scanning electron microscopy, energy dispersive spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results show that the butyl xanthate in solution reacts with copper sulfate to form cupric xanthate, increasing the consumption of the collector butyl xanthate and resulting in lower floatability of pyrite. Cupric xanthate can be adsorbed on the pyrite surface through bonding with the sulfur sites. The adsorbed cupric xanthate on the pyrite surface undergoes redox reaction. The cupric xanthate is reduced to cuprous xanthate, and the sulfur on the surface will be oxidized. The adsorption products on the pyrite surface contain both cuprous xanthate and cupric xanthate. As the pH of a solution increases, the absolute value of the zeta potential of pyrite surface increased and the surface contact angle increased. Iron xanthate is also formed on the pyrite surface through a chemical reaction between the xanthate ions and pyrite, oxidation of xanthate ions to dixanthogen also takes place. Cuprous xanthate is the main hydrophobic substance on the pyrite surface, which can change the surface electrical properties and wettability of pyrite, and improve hydrophobicity of pyrite.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 3; 46-60
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:

Adsorption Behavior of Glucuronic Acid on Pyrite Surface: an electrochemical and DFT Study

Autorzy:

Ning, Xu Jia
Ying, Yang Hong
Lin, Tong-Lin

Powiązania:

https://bibliotekanauki.pl/articles/355049.pdf

Data publikacji:

2020

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

glucuronic acid
pyrite
adsorption

Opis:

Bacterial adsorption on mineral surface is one of the key steps in bioleaching process. The bacteria adsorb on the mineral surface via the extracellular polymeric substances (EPS) layer. In this paper, the behavior of glucuronic acid, one of the key substances in EPS layer, adsorbed on the pyrite surface is studied using DFT and electrochemical methods. Adsorption capacity of glucuronic acid is stronger than that of water. Glucuronic acid adsorbs on pyrite surfaces and it follows a mixed type of interactions (physisorption and chemisorption). Adsorption of glucuronic acid on pyrite surface followed Langmuir’s adsorption isotherm with adsorption standard free energy of –27.67kJ mol^-1. The structural and electronic parameters were calculated and discussed.

Źródło:

Archives of Metallurgy and Materials; 2020, 65, 1; 433-440
1733-3490

Pojawia się w:

Archives of Metallurgy and Materials

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 10.

Tytuł:

Mineralogical and morphological studies of gold-bearing arsenopyrite and pyrite minerals of Bakyrchik and Bolshevik gold black shale deposits (Eastern Kazakhstan)

Autorzy:

Junussov, M.
Umarbekova, Z.

Powiązania:

https://bibliotekanauki.pl/articles/100802.pdf

Data publikacji:

2018

Wydawca:

Uniwersytet Śląski. Wydział Nauk o Ziemi

Tematy:

Bakyrchik
gold-bearing arsenopyrite and pyrite
acicular-prismatic arsenopyrite
cubic pyrite
złoże
arsenopiryt
złoto
piryt
skład chemiczny
metoda badań

Opis:

Bakyrchik and Bolshevik both are sediment-hosted disseminated gold deposits. They are located in Eastern Kazakhstan (4 km in distance between deposits) and include in the Western Qalba metallogenic zone. They originated in late Paleozoic age along structured line between palaeocontinents of Kazakhstan and Altai-Mongol. The purpose of this paper is designation of typomorphic features of gold-bearing arsenopyrite and pyrite minerals, determination of chemical composition of these two sulfides minerals. The arsenopyrite and pyrite are the main objects for analytical study of gold-bearing sulfide minerals, their different textures, morphology of the crystals and aggregates. The studies of ore samples and minerals were carried out by methods of optical microscope, X-ray diffraction, X-ray fluorescence and electron microprobe analyses. The analytical study of sulphide minerals has shown that the arsenopyrite is acicular and tabular, pyrite has three varieties - globular, hexahedral and pentahedral forms in three rock samples of the carbonaceous-terrigenous formation in the deposits.

Źródło:

Contemporary Trends in Geoscience; 2018, 7, 2; 153-165
2299-8179

Pojawia się w:

Contemporary Trends in Geoscience

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 11.

Tytuł:

A study on the effect of active pyrite on flotation of porphyry copper ores

Autorzy:

Molaei, N.
Hoseinian, F. S.
Rezai, B.

Powiązania:

https://bibliotekanauki.pl/articles/109515.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

flotation
optimization
collector
chalcopyrite
active pyrite

Opis:

Active pyrite is one of the most undesirable phenomena in the flotation of porphyry copper ores. Misreported pyrite into copper concentrates decreased the grade and recovery of copper. In this study, the effective parameters on the flotation process including grinding condition and chemical parameters were evaluated in order to decrease the active pyrite recovery by flotation. Firstly, optical microscopic and grinding studies were carried out to determine the optimal particle size and grinding time. The results showed that 43 minutes of grinding is necessary to achieve the optimum liberation degree of 53 µm for flotation. Then, the flotation effective parameters such as pH (7.3, 10, 10.5, 11, 11.5 and 12), collector type (Nascol, Aero 407, Aero 3477 and X231), collector concentration (12 and 25 mg/dm3), depressant concentration (0 and 25 mg/dm3) and frother concentration (0 and 25 mg/dm3) were investigated in a Denver-type laboratory flotation cell with a constant capacity of 2.5 dm3. The results showed that the optimal conditions for chalcopyrite flotation were pH of 11.5, Aero 407 as a collector with concentration of 25 mg/dm3, Dowfroth 250 (DF250) as a frother with concentration of 25 mg/dm3 and Na2SO3 as a depressant with concentration of 25 mg/dm3. The type of collector had greater effect on the chalcopyrite flotation than the other parameters. The recovery and grade of chalcopyrite and pyrite were obtained as 79.95%, 49% and 5.3%, 7.98% using the Aero 407, respectively. Under the optimum conditions, the grade of final concentrate increased from 0.94% to 21.3% with three cleaner stages.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 3; 922-933
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 12.

Tytuł:

Pyrite oxidation inhibition by hydrophobic films for acid mine drainage control at the source

Autorzy:

Wang, Shuncai
Zhao, Yue
Li, Shuang

Powiązania:

https://bibliotekanauki.pl/articles/110200.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

hydrophobic film
pyrite
suppression
linoleic acid
acid mine drainage

Opis:

Acid mine drainage (AMD), which is also known as acid rock drainage (ARD), can cause serious environmental pollution, especially for surrounding aquatic and terrestrial ecosystems due toits low pH, high metal and sulfate concentration. Acid mine drainage is an urgent environmental problem for the worldwide ore mining industry. In this paper, we demonstrated that hydrophobic films can inhibit the oxidation of pyrite-bearing tailings to achieve the control of at-source AMD. The results of chemical leaching testing showed that the hydrophobic films formed by linoleic acid can suppress the oxidation of pyrite-bearing tailings and reduce the AMD production. In addition, the presence of hydrophobic films of linoleic acid on the surface of pyrite-bearing tailings was confirmed by the results from Fourier transform infrared (FTIR) analyses and scanning electron microscopy with energy dispersive spectrometry (SEM / EDS).

Źródło:

Physicochemical Problems of Mineral Processing; 2019, 55, 5; 1132-1140
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 13.

Tytuł:

First-principles study on the adsorption structure of water molecules on a pyrite (100) surface

Autorzy:

Liu, Yingchao
Chen, Jianhua
Li, Yuqiong
Zhang, Junjie
Kang, Duan

Powiązania:

https://bibliotekanauki.pl/articles/1447970.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
water molecules
adsorption

Opis:

The hydration structure of water molecule adsorption at different coverages of a monolayer on a pyrite (100) surface were simulated using the density functional theory (DFT) method. The results demonstrate that the Fe-O interaction weakens and the adsorption energy per water molecule decreases with increasing water coverage, except at a monolayer coverage of 12/12 (i.e., full coverage). H-S and H-O hydrogen bonds were formed on the nearest surface layer. When large amounts of water molecules adsorb onto the surface, the adsorbed water molecules can be divided into three layers: the layer nearest to the surface, the second nearest to the surface, and the layer farthest from the surface. The thickness of the former two layers is approximately 5.5 Å. The three layers have water densities of 1.12 g/cm3, 1.08 g/cm3, and 0.95 g/cm3, respectively, suggesting that there is a strong interaction between the pyrite surface and water molecules and the influence of surface structure on water adsorption reaches a distance of more than 10 Å. Dynamics simulations suggest that the water molecules close to the mineral surfaces are in an orderly arrangement while those far from the surface are disordered.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 2; 121-130
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 14.

Tytuł:

Impact of ovalbumin on pyrite flotation in the absence and presence of metal ions

Autorzy:

Guler, T.
Sahbudak, K.
Akdemir, U.
Cetinkaya, S.

Powiązania:

https://bibliotekanauki.pl/articles/110499.pdf

Data publikacji:

2014

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
ovalbumin
metal ion
flotation
redox potential

Opis:

Recovery of gangue pyrite and its accidental activation are vital issues in flotation of complex sulfide ores. This work was performed by cyclic voltammetry (CV) and flotation tests to elucidate applicability of ovalbumin (OVA) as depressant for pyrite. The synergetic effect of metal ions in addition to its possible use in case of accidental activation by metal ions. CV tests stated that OVA adsorbed irreversibly on pyrite, and restricted electron transfer up to moderately oxidizing potentials due to electrostatic interaction together with weak hydrophobic interactions. At highly oxidizing potentials, adsorption occurred through electrochemical mechanisms through formation of metal-OVA chelates. Rate of pyrite depression with OVA was found to be potential dependent reaching its peak point around moderately oxidizing potentials both in absence and presence of metal ions. Electrochemically active metals display synergetic effect with OVA on pyrite depression, whereas noble metals activate pyrite and reduced depressing potency of OVA.

Źródło:

Physicochemical Problems of Mineral Processing; 2014, 50, 1; 31-40
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 15.

Tytuł:

Adsorption of yeast dextran on clinochlore surface and the implications for pyrite/clinochlore separation

Autorzy:

Wang, Zhen
Zou, Dan
Zhao, Kaile
Safarov, Sayfidin
Xu, Ying

Powiązania:

https://bibliotekanauki.pl/articles/2146917.pdf

Data publikacji:

2022

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

clinochlore
pyrite
flotation
yeast dextran
adsorption

Opis:

Silicate minerals with a certain degree of flotability are often easy to mix into sulfide ore concentrate in mineral processing industry. In this paper, the adsorption of yeast dextran on clinochlore and its application in pyrite/clinochlore separation were investigated. The adsorbed amount and micro polarity measurement results displayed that the yeast dextran molecules selectively adsorbed onto clinochlore surface compared with pyrite. The adsorbed yeast dextran resulted in the increase in the surface polarity of clinochlore surface, and inhibited the further adsorption of xanthate, thus keep it hydrophilic and depressed. Quantum chemical computation results indicated that yeast dextran was mainly adsorbed on mineral surface by the chelation with the surface metal active sites, and the chelating strength of yeast dextran with three ions was in the sequence of Fe3+ > Mg2+ > Fe2+. While Mg2+, Fe2+ and Fe3+ are the main metal ions on the surface of clinochlore, and Fe2+ is the unique metal ions on pyrite surface. This is the reason of the selectivity of the yeast dextran depressant for pyrite/clinochlore flotation system. The flotation results demonstrated that yeast dextran was qualified to selectively depress clinochlore in pyrite flotation.

Źródło:

Physicochemical Problems of Mineral Processing; 2022, 58, 4; art. no. 151635
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 16.

Tytuł:

Application of EIS technique to investigate the adsorption of different types of depressants on pyrite

Autorzy:

Ertekin, Zeliha
Pekmez, Kadir
Kappes, Ronel
Ekmekçi, Zafir

Powiązania:

https://bibliotekanauki.pl/articles/1447279.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
depressants
collector
mineral electrodes
electrochemical impedance spectroscopy

Opis:

Batch scale flotation tests are generally performed for testing effects of flotation reagents on flotation performance. This method becomes costly and time-consuming for testing a number of flotation reagents such as collectors, depressants and activators. Therefore, developing alternative lowcost, fast and sensitive methods have recently been the subject of intense research to obtain a better flotation performance. The electrochemical techniques have been used for the surface characterization of sulfide minerals. Electrochemical Impedance Spectroscopy (EIS) is one of these techniques that can provide significant information related to surface characteristics, reagent adsorption on the sulfide minerals. In this study, EIS was used as an alternative technique to the conventional batch scale flotation tests for pre-screening of various flotation reagents using two pyrite samples containing different contents of Au and As. Sodium cyanide (NaCN), sodium metabisulfite (SMBS), and a polymeric depressant Aero 7261A were tested as depressants for two pyrite samples (Sample A from a Carlintrend ore and Sample B from a Sulfidic ore from South America) having different electrochemical characteristics. EIS results showed that the effects of the sequence of addition of collector (Potassium amyl xanthate - KAX) and depressant were also investigated to evaluate the stability of depressant and collector compounds formed at the surface. The sequence of addition of the collector and depressants was significant for Sample A but not for Sample B. The results show that EIS can be used as an effective tool for testing the performance of various flotation reagents and their mixtures on sulfide minerals.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 3; 112-126
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 17.

Tytuł:

Comparison study of crystal and electronic structures for chalcopyrite $(CuFeS_2)$ and pyrite $(FeS_2)$

Autorzy:

Li, Yuqiong
Liu, Yingchao
Chen, Jianhua
Zhao, Cuihua
Cui, Weiyong

Powiązania:

https://bibliotekanauki.pl/articles/1448811.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

chalcopyrite
pyrite
crystal structures
electronic structures

Opis:

Chalcopyrite $(CuFeS_2)$ and pyrite $(FeS_2)$ are commonly associated with each other, and they both belong to semiconductor minerals. The difference in crystal and electronic structures is an important factor for their flotation separation. Using the density functional method (DFT) combined with Hubbard U correction, their crystal and electronic properties are comparatively studied. The calculated results suggest that the use of antiferromagnetic calculations and Hubbard U correction are very important to the accuracy of the chalcopyrite results. Antiferromagnetic calculations combined with a U value of 2.0 eV on chalcopyrite show a band gap of 0.53 eV, which is very consistent with the experimental results of ~0.5 eV. The density of states (DOS) and Mulliken bond population results indicate that stronger hybridization between Fe 3d and S 3p states in chalcopyrite than in pyrite leads to a stronger covalency of Fe-S bonds in chalcopyrite, causing a reduction in the spin magnetic moment (3.5 μB) from the ideal value. In addition, the greater covalency of bonds in chalcopyrite results in greater hydrophobicity of chalcopyrite than pyrite. The DOS results suggest that S has similar electronic properties in pyrite and chalcopyrite. The oxidation states of Fe and Cu ions in chalcopyrite are discussed based on the coordination field theory according to the calculation results, which confirms an oxidation state of $Fe^{3+}Cu^{1+}S_2$.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 1; 100-111
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 18.

Tytuł:

Authigenic pyrite framboids in sedimentary facies of the Mount Wawel Formation (Eocene), King George Island, West Antarctica

Autorzy:

Mozer, Anna

Powiązania:

https://bibliotekanauki.pl/articles/2051592.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

Antarctica
King George Island
Eocene
framboidal pyrite
bacterial sulphate reduction
sulphur isotopes

Źródło:

Polish Polar Research; 2010, 3; 255-272
0138-0338
2081-8262

Pojawia się w:

Polish Polar Research

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 19.

Tytuł:

Response surface methodology (RSM) for optimization of chalcopyrite concentrate leaching with silver-coated pyrite

Autorzy:

Salehi, S.
Noaparast, M.
Shafaei, S. Z.

Powiązania:

https://bibliotekanauki.pl/articles/110894.pdf

Data publikacji:

2016

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

chalcopyrite
copper extraction
silver-coated pyrite
optimization
response surface methodology

Opis:

This study aims to leach copper from chalcopyrite and optimizing the leaching process, using the response surface methodology (RSM). The RSM, a D-optimal design with four factors in three levels was employed to evaluate the effect of particle size, temperature, silver-coated pyrite to chalcopyrite ratio and redox potential parameters on the copper extraction efficiency. A quadratic model was then proposed by the RSM to correlate leaching variables. The tests results indicated that the model was significant with the experimental data at a correlation coefficient (R2) of 0.96. The most important parameters of copper extraction efficiency were particle size and silver-coated pyrite-to-chalcopyrite ratio, and also the squared term of particle size (A2), temperature (B2) and redox potential (D2). In addition, the interaction between redox potential and silver-coated pyrite-to-chalcopyrite ratio (CD) was significant. It was shown that the finer the particle size the faster the leaching rate of copper. It was also indicated that by increasing silver-coated pyrite to chalcopyrite ratio of 6:1 copper recovery increased. The maximum recovery of copper (71%) was obtained for the particle size of -38 μm, 70 °C, 420 mV of redox potential, silver-coated pyrite-to-chalcopyrite ratio of 6 and leaching time of 8 hours.

Źródło:

Physicochemical Problems of Mineral Processing; 2016, 52, 2; 1023-1035
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 20.

Tytuł:

Flotation kinetics and thermodynamic behavior of chalcopyrite and pyrite in high alkaline systems

Autorzy:

Yan, H.
Yuan, Q.
Zhou, L.
Qiu, T.
Ai, G.

Powiązania:

https://bibliotekanauki.pl/articles/110078.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

flotation kinetics
pyrite
chalcopyrite
flotation separation
high alkaline
microcalorimetry

Opis:

The monomineral flotation test and microcalorimetry were used to study the flotation kinetics and thermodynamic behavior of chalcopyrite and pyrite in high alkaline systems of lime and NaOH. The results showed that in these systems there were less hydrophilic substances on the chalcopyrite surface, so that the apparent activation energy of sodium butyl xanthate (SBX) adsorption on chalcopyrite surface was low. This promoted the adsorption of SBX and increased the flotation rate and recovery of chalcopyrite. In contrast, the hydrophilic Fe(OH)3 and SO42- formed by oxidation on the pyrite surface increased the adsorption activation energy of SBX. Thus, the flotation rate and recovery of pyrite were lower. Moreover, in the lime high alkaline system, the hydrophilic calcium film generated on the pyrite surface further hindered the adsorption of SBX, thereby further inhibiting pyrite in this environment. In other words, the lime high alkaline environment increased the apparent activation energy difference of SBX adsorption between chalcopyrite and pyrite compared to the NaOH system, facilitating the flotation separation of chalcopyrite and pyrite. The results can help with the theoretical research of flotation separation of other minerals, and provide guidance for developing low alkaline and lime-free pyrite depressants.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 3; 901-910
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 21.

Tytuł:

Insight into the effect of galvanic interactions between sulfide minerals on the floatability and surface characteristics of pyrite

Autorzy:

Yang, Bo
Tong, Xiong
Xie, Xian
Huang, Lingyun

Powiązania:

https://bibliotekanauki.pl/articles/1448232.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

galvanic interaction
floatability
pyrite
sulfide minerals

Opis:

Complex sulfide ores are usually found as a mixture of various sulfide and gangue minerals, and froth flotation is the predominant method for the selective separation of sulfide minerals. Adherence and contact between sulfide minerals are inevitable during froth flotation, and galvanic interactions between sulfide minerals will occur because of differences in rest potentials. However, the effect of these galvanic interactions on the selective flotation of sulfide minerals have been rarely studied. In this work, the effect of the galvanic interaction between pyrite and sphalerite on the flotation behavior and surface characteristics of pyrite was investigated by micro-flotation tests, collector adsorption tests, electrochemical techniques and XPS (X-ray photoelectron spectroscopy) surface analysis. The micro-flotation tests indicated that the floatability of pyrite decreased in the pH range of 4.0 to 9.5 and increased under strongly alkaline pH conditions (pH > 10) due to the galvanic interaction. The collector adsorption results demonstrated that the adsorption capacity of the collector on the pyrite surface was significantly reduced because of the galvanic interaction between pyrite and sphalerite. The electrochemical measurements revealed that the decrease in the oxidation current of xanthates to dixanthogen was responsible for the decreasing adsorption capacity of the collector on the pyrite surface. The XPS results indicated that the formation of the $S_O_3^{2-}$ oxidation product on the pyrite surface decreased at a strongly alkaline pH due to the galvanic interaction. Therefore, pyrite floatability improved at an alkaline pH. These results consistently showed that the galvanic interaction between pyrite and sphalerite had an important influence on the floatability and surface characteristics of pyrite.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 2; 24-33
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 22.

Tytuł:

Evaluation of pyritic tailings from a copper concentration plant for calcareous sodic soil reclamation

Autorzy:

Tozsin, G.
Arol, A. I.
Cayci, G.

Powiązania:

https://bibliotekanauki.pl/articles/109593.pdf

Data publikacji:

2014

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

waste pyrite
gypsum
pyrite oxidation
column leaching test
sodic soil
reclamation

Opis:

This study was aimed to investigate the feasibility to use waste pyrite and sulphuric acid produced from waste pyrite for the reclamation of calcareous sodic soils. The final aim is to displace Na from an exchange complex and replace it with Ca, leading to a decrease in pH and exchangeable sodium percentage (ESP) and an improvement of soil structure. A fertility of the soil may also be enhanced by this technique since waste pyrite can be rich in several micronutrients. An additional advantage to this strategy is that waste pyrite is inexpensive and readily available in large quantities, by contrast to gypsum. In this study, column-leaching tests were carried out to evaluate a change in soil properties upon addition of gypsum and pyritic tailing amendments from a copper concentration plant. An availability of essential micronutrients for a plant growth (Fe, Cu, Zn and Mn) and hazardous potential of pyritic tailings in terms of heavy metal contamination were taken into account. Gypsum, powder waste pyrite and sulfuric acid produced from waste pyrite were applied to the soil with reference to the gypsum requirement (GR) of the soils. The results showed that application of waste pyrite with a dose of 44.74 megagrams per ha was superior to gypsum of 55.20 Mg/ha dose in terms of exchangeable sodium percentage (ESP) in 42 weeks. In addition, application of all the concentrations of sulfuric acid produced from waste pyrite also decreased the ESP values. The best values with sulfuric acid were obtained with a dose of 35.31 Mg/ha in 26 weeks. It was observed that the content of all micronutrients in the soil increased significantly (P<0.01) with waste pyrite and sulfuric acid applications. The levels of the micronutrients after treatments can be classified sufficient for the plant growth except for the iron level with the minimum dose of sulfuric acid application 17 Mg/ha. The heavy metal content in the soil after treatment with the pyritic tailings was found to be lower than the legal limit values. Thus, waste pyrite can be effectively used since rapid amelioration of calcareous sodic soils is possible with no deleterious heavy metal contamination.

Źródło:

Physicochemical Problems of Mineral Processing; 2014, 50, 2; 693-704
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 23.

Tytuł:

New insights into pyrite-hydrogen peroxide interactions during froth flotation: experimental and DFT study

Autorzy:

Cao, Qinbo
Yan, Wenchao
Wen, Shuming
Liu, Dianwen
Li, Yanjun

Powiązania:

https://bibliotekanauki.pl/articles/2200334.pdf

Data publikacji:

2023

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

hydrogen peroxide
oxidization
pyrite flotation
adsorption models
DFT

Opis:

Hydrogen peroxide (H2O2) is an efficient depressant for pyrite (FeS2) flotation. However, the depressing mechanism of H2O2 is not fully understood. In this paper, the depressing capacity of H2O2 for pyrite was examined by flotation tests. Results revealed that pyrite flotation could be inhibited by H2O2 at pH 6.4. The pyrite powder in H2O2 solution enhanced the release of O2 from H2O2. However, the O2 concentration in the solution was less than that of H2O2; thus, H2O2 is the major oxidant in the solution. Moreover, density functional theory calculations were performed to study the interactions between H2O2 and hydrated pyrite (100) surface. The H2O2 molecule tended to react with the pyrite surface to generate one S=O bond and an H2O molecule. The possible binding models of O2 molecules on the pyrite (100) surface were also studied for comparison. The O2 dissociation on the pyrite surface was more favorable than the adsorption of O2 as a whole. In addition, the orbital interaction in the S=O bond raised from the reaction of H2O2/O2 with the pyrite surface was also investigated by the density states analysis. These results provide some insights into the oxidizing effect of H2O2 in pyrite flotation.

Źródło:

Physicochemical Problems of Mineral Processing; 2023, 59, 1; art. no. 157409
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 24.

Tytuł:

Efficient sulfidization of lead oxide at high temperature using pyrite as vulcanizing reagent

Autorzy:

Zheng, Y.-X.
Lv, J.-F.
Wang, H.
Wen, S.-M.
Huang, L.

Powiązania:

https://bibliotekanauki.pl/articles/110351.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

lead oxide
sulfidization roasting
pyrite
reaction mechanism
TG

Opis:

A sulfidization roasting-flotation process was usually viewed to be effective in treating the refractory oxide ore. In this paper, pyrite was proposed to be applied as a potential vulcanizing reagent to transform PbO or its surface to PbS based on feasibilities of technology and economy. The evolution process, phase and characteristics of crystal growth were investigated by TG, XRD and SEM-EDS, respectively, to interpret the interaction mechanism of lead oxide and pyrite at high temperature. It was found that the decomposition process of pyrite under argon atmosphere was a slow process of sulfur released from FeS2 to FexS, which made the process easier to be controlled. When PbO was introduced into the system, the initial solid-solid (PbO-FeS2) reaction and prevailing solid-gas (PbO-S2(g)) reaction occurred at about 500 °C and 700 °C, respectively. Combined with the SEM-EDS analyses results, the optimal temperature for the sulfidization of PbO should be in the range of 700-750 °C.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 2; 270-277
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 25.

Tytuł:

Effect of externally adding pyrite and electrical current on galvanic leaching of chalcopyrite concentrate

Autorzy:

Asgari, Kaveh
Hassanzadeh, Ahmad
Nazari, Sabereh
Vakylabad, Ali Behrad
Hosseinzadeh, Mostafa

Powiązania:

https://bibliotekanauki.pl/articles/1447957.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

copper concentrate
galvanic leaching
pyrite
electrical current
leaching kinetics

Opis:

Although the operating properties of GalvanoxTM leaching have been widely studied in the literature, several factors concerning chalcopyrite passivation during the process remain unknown so far. The present work hence aims at investigating the significant effect of externally added pyrite features with a particular focus on its particle size (d80 of 0.52, 20, 45 and 2000 µm) through a series of experiments performed in a 2-L stirred-tank electro-reactor. To this end, the role of pyrite: chalcopyrite ratio (0.49:1, 2:1 and 4:1) and presence of electrical current were examined while the rest of the parameters kept constant (80 °C temperature, 400–500 mV (Ag/AgCl) redox potential, pulp density of 10% (w/v), and stirring rate of 1200 rpm). Plus, kinetic models of the leaching tests were studied based on the diffusion and chemical controlling concepts. It was found that the coarser the pyrite particles, the more favorable the copper extraction from the concentrate due to acceleration of reactions in the cathodic electrode and high mass transfers. However, this was in contradiction with the existing reports in the literature. Moreover, galvanic interactions became intensive in the presence of pyrite meaning extensive chalcopyrite dissolution with significantly reduced passivation. Ultimate copper extraction values of 24.17±1.25%, 55.79±0.91% and 57.26±1.59% were resulted at Py:Cp ratios of 0.49:1 (natural), 2:1 and 4:1, respectively. The results showed that maximum copper recovery of 67.32±2.34% was obtained at an optimum condition of pyrite grain size=2000 µm, Py:Cp=4:1, current application=500 mA, 8 h and 80 °C. Finally, detailed kinetic modeling indicated that the chemical control mechanism was dominant in the early reaction stages (t<3.5 h) concerning the availability of fresh surface for chemical agents; however, the second half of the process (8.0 h>t>3.5 h) was controlled by the diffusion control.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 2; 105-119
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 26.

Tytuł:

Study on surface modification of cerussite by thermochemical processing with pyrite

Autorzy:

Zheng, Yong-Xing
Ning, Ji-Lai
Xie, Haiyun
Lv, Jin-Fang
Hu, Pan-Jin
Pang, Jie

Powiązania:

https://bibliotekanauki.pl/articles/1448573.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

cerussite
pyrite
surface modification
thermochemical processing
flotation

Opis:

In this paper, surface modification of cerussite by thermochemical processing with pyrite was studied based on microflotation tests, X-ray powder diffractometry (XRD), X-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). Microflotation test results showed that the surface modification facilitated flotation of the treated cerussite and improved the flotation recovery to approximately 90%. The results of XRD analyses confirmed that cerussite was transformed into massicot, which then interacted with pyrite to form $PbS$, $PbSO_4$, $PbO•PbSO_4$ and $4PbO•PbSO_4$. XPS analyses results revealed that both $PbS$ and $PbS_2$ were formed on the mineral surface, and the percentage of $PbS$ increased with increasing $FeS_2$/$PbCO_3$ (F/P) mole ratio, which was advantageous for the flotation of the modified cerussite. EPMA analyses showed that particles with layered configurations were obviously formed after thermochemical processing. The thickness of the products at the outer layer of the particles increased when the F/P mole ratio increased. Moreover, the S and O contents in the products increased and decreased, respectively.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 1; 156-167
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 27.

Tytuł:

Structure-activity of chelating depressants for chalcopyrite/pyrite separation: DFT study and flotation experiment

Autorzy:

Li, Mingyang
Lian, De
Zhao, Fugang
Tong, Xiong
Wu, Chaoyang
Gao, Xiangpeng

Powiązania:

https://bibliotekanauki.pl/articles/2146867.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

chelating depressants
activity
pyrite
DFT calculations
frontier orbitals

Opis:

Three types of chelating depressants were studied for chalcopyrite/pyrite separation, including S-S, S-O, and O-O types, via density functional theory calculations and microflotation. The calculation results indicate that the depressant’s chelating atoms have large coefficient and great activity according to the molecular frontier orbital (HOMO and LUMO) and the orbital coefficients. For S-S type of depressant, S atom in both keto or enol forms won’t affect their HOMO and LUMO patterns and the orbital contributions. For S-O type, the presence of N atom in the ring structure of a molecular will increase the reactivity of O-Cu while weak S-Cu. For O-O type, the electron supply capacity of benzene ring is higher than strain chain, and atom N in strain chain increased their electron supply capacity. The microflotation results basically confirmed the prediction based on the calculation. The simulation results demonstrate that the interaction of a depressant with metals and minerals are affected obviously by the spatial structure and electronic structure of an atom in its molecular.

Źródło:

Physicochemical Problems of Mineral Processing; 2021, 57, 6; 102--112
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 28.

Tytuł:

Geomicrobiology of Acid Mine Drainage in the weathering zone of pyrite-bearing schists in the Rudawy Janowickie Mountains (Poland)

Autorzy:

Borkowski, A.
Parafiniuk, J.
Wolicka, D.
Kowalczyk, P.

Powiązania:

https://bibliotekanauki.pl/articles/2060320.pdf

Data publikacji:

2013

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

Acid Mine Drainage
microbial communities
pyrite
weathering zone

Opis:

This paper presents the geomicrobiological analysis of acid water reservoirs and Acid Mine Drainage (AMD) developed in the weathering zone of pyrite-bearing schists near the closed-down pyrite mine in Wieściszowice (south-western Poland). The analysis was focused on two reservoirs characterized by different physical and chemical properties (pH, redox potential, content of sulphates and heavy metals). The study is the first thorough report on the geomicrobiological relationships taking place in the AMD setting in Wieściszowice and enables a description of the microbiological processes that significantly influence biogeochemical cycles of sulfur and iron in the analyzed water reservoirs. The reservoir water also harbors numerous big, organized microbial structures in the form of streamers. Samples of these structures were studied in detail using optical and electron microscopy, as well as microbiological cultivation and molecular methods. According to the obtained results, the slime streamers from the Wieściszowice mine are characterized by the co-occurrence of typical chemolithoautotrophic microorganisms oxidizing sulphur and iron together with sulphate reducing bacteria. The presence of these structures probably depends on the occurrence of iron (II) in the surrounding environment.

Źródło:

Geological Quarterly; 2013, 57, 4; 601--612
1641-7291

Pojawia się w:

Geological Quarterly

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 29.

Tytuł:

Effect of microwave system location on floatability of chalcopyrite and pyrite in a copper ore processing circuit

Autorzy:

Gholami, Hamed
Rezai, Bahram
Mehdilo, Akbar
Hassanzadeh, Ahmad
Yarahmadi, Mohammadreza

Powiązania:

https://bibliotekanauki.pl/articles/109728.pdf

Data publikacji:

2020

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

microwave technology
chalcopyrite
pyrite
comminution circuits
separation efficiency

Opis:

The present work aims at investigating the effect of microwave local positions (i.e. before crushing (BC), after crushing (AC) and after milling (AM)) on microwave-assisted flotation of chalcopyrite and pyrite in a porphyry copper complex deposit. Individual given samples for each state were pre-treated with a variable power microwave at a power level of 90 to 900W for 15, 30, and 60s. Furthermore, froth floatation experiments were carried out using a laboratory mechanical Denver flotation cell on both microwave-treated and untreated samples. Particle surface properties were characterized by a scanning electron microscopy (SEM) and an energy-dispersive X-ray spectroscopy (EDX) analysis. The results showed that the chalcopyrite and pyrite floatabilities increased monotonically by rising the exposure time and power level for the uncrushed preconditioned samples (BC) due to the enhancement of mineral liberation degrees together with the formation of sulphide species and polysulphides on the mineral surfaces. However, flotation results of treated samples for the crushed one (AC) revealed an optimum range. Formation of intensive oxide layers on the mineral surfaces of milled samples (AM) led to a substantial reduction in their recoveries by increasing the microwave’s power level and the sample’s exposure time. The results obtained from mineral’s floatabilities in recleaner stage showed that the microwave-assisted sample at 900W for 30s at BC state favourably provided 5% higher S.E.’s than that of the untreated sample. Finally, it was concluded that the microwave pretreatment of samples induced the best floatability responses if it located before the crusher.

Źródło:

Physicochemical Problems of Mineral Processing; 2020, 56, 3; 432-448
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 30.

Tytuł:

A nanoparticle cationic polystyrene-co-poly(n-butylacrylate) collector to eliminate the negative effect of lizardite slimes in pyrite flotation

Autorzy:

Ai, Guanghua
Liu, Cheng
Zhu, Guangli
Yang, Siyuan

Powiązania:

https://bibliotekanauki.pl/articles/24085927.pdf

Data publikacji:

2023

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

nanoparticle collector
pyrite
lizardite slimes
flotation separation

Opis:

Lizardite slime coating is one of significant factors in the deterioration of the floatability of sulphide minerals. In this study, a nanoparticle cationic polystyrene-co-poly(n-butylacrylate)(PS-PBNH) collector was introduced to eliminate the negative impact of lizardite slimes in pyrite flotation. Microflotation results demonstrated that lizardite slims did not affect the recovery of pyrite in the presence of PS-PBNH. Good flotation separation of pyrite from lizardite was achieved when the nanoparticle PS-PBNH collector was used. The results from adsorption study indicated that PS-PBNH exhibited a significant adsorption on the pyrite surface in the presence of lizardite slimes. Sedimentation tests showed that hetero-aggregation occurred between lizardite slimes and pyrite, whereas the introduction of PS-PBNH collector resulted in a heterogeneous dispersion between them. Zeta potential measurements suggested that PS-PBNH collector interacted with pyrite surface, and the PS-PBNH adsorption changed the surface charge of pyrite from negative to be positive. As a result, the interaction of pyrite with lizardite shifted from electrostatic attraction to electrostatic repulsion, as supported by the DLVO calculations. These results indicated PS-PBNH can be used as a potential collector for pyrite flotation in pyrite/lizardite slimes system without the need for a depressant.

Źródło:

Physicochemical Problems of Mineral Processing; 2023, 59, 3; art. no. 170899
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 31.

Tytuł:

Galvanic contacting effect of pyrite on xanthate adsorption on galena surface: DFT simulation and cyclic voltammetric measurements

Autorzy:

Ke, B.
Chen, J.
Li, Y.
Chen, Y.

Powiązania:

https://bibliotekanauki.pl/articles/110904.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

adsorption
DFT
galvanic interaction
pyrite surface
galena surface
cyclic voltammetric measurements

Opis:

The effect of galvanic interaction between pyrite and galena on xanthate adsorbing on the galena surface has been investigated by means of density functional theory (DFT) and cyclic voltammetric measurements. The calculated results show that differences in the contact site and contact distance between galena and pyrite can affect the intensity of the galvanic interaction, and the relationship between the intensity of galvanic interaction and the adsorption ability of xanthate on galena surface has been studied in detail. In general, the galvanic interaction between pyrite and galena surface can enhance the adsorption of xanthate on the galena surface. The adsorption energies of xanthate on the galena surface decrease with the decrease of contact distance, and when the contact distance is lower than 4 Å, the adsorption energies decrease significantly at Pb-Pb, Pb-S and S-S sites. In particular, at the contact distance of 3 Å, a sharp decrease of adsorption energy is observed at the Pb-Pb contact site; in this case, the negative shift of the Pb-S bonding range and DOS non-locality at Pb-Pb contact site are significantly greater than that of the S-S or Pb-S contact sites. The cyclic voltammetric measurements reveal that the galvanic interaction between galena and pyrite improves the adsorption of xanthate on galena surface, which is in good agreement with the DFT results.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 3; 826-836
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 32.

Tytuł:

Investigating the selectivity of calcium hypochlorite for flotation separation of chalcopyrite and pyrite pre-adsorbed collector

Autorzy:

Yang, Wenhui
Qiu, Xianhui
Yan, Huashan
Wu, Hao
Yang, Liu
Lai, Ruisen
Qiu, Tingsheng

Powiązania:

https://bibliotekanauki.pl/articles/2146919.pdf

Data publikacji:

2022

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
chalcopyrite
calcium hypochlorite
flotation separation

Opis:

Bulk flotation is usually used in the flotation of Cu-Fe sulfide ore, and the subsequent concentrate is difficult to be separated because the minerals have adsorbed the collector. In this paper, flotation tests showed that calcium hypochlorite (Ca(ClO)2) had a stronger depression effect on pyrite pre-adsorbed sodium butyl xanthate (SBX), while having a negligible depressive effect on chalcopyrite. A copper concentrate with Cu grade of 33.32% and Cu recovery of 94.47% could be obtained from flotation tests of mixed minerals. The depression performance and mechanism of Ca(ClO)2 were studied by contact angle measurements, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses, the results suggested that Ca(ClO)2 can decomposes SBX on the pyrite surface and oxidizes the mineral surface to form hydrophilic substances, which enhances the hydrophilicity of the pyrite surface. In contrast, Ca(ClO)2 has little effect on chalcopyrite pre-adsorbed SBX, the possible depression model is discussed.

Źródło:

Physicochemical Problems of Mineral Processing; 2022, 58, 4; art. no. 150703
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 33.

Tytuł:

Ordovician Jeleniów Claystone Formation of the Holy Cross Mountains, Poland - Reconstruction of redox conditions using pyrite framboid study

Autorzy:

Smolarek, J.
Marynowski, L.
Trela, W.

Powiązania:

https://bibliotekanauki.pl/articles/100786.pdf

Data publikacji:

2014

Wydawca:

Uniwersytet Śląski. Wydział Nauk o Ziemi

Tematy:

ordowik
piryt
Jeleniów
Góry Świętokrzyskie
ordovician
pyrite framboids
redox conditions
Jeleniów Formation

Opis:

The aim of this research is to reconstruct palaeoredox conditions during sedimentation of the Jeleniów Claystone Formation deposits, using framboid pyrite diameter measurements. Analysis of pyrite framboids diameter distribution is an effective method in the palaeoenvironmental interpretation which allow for a more detailed insight into the redox conditions, and thus the distinction between euxinic, dysoxic and anoxic conditions. Most of the samples is characterized by framboid indicators typical for anoxic/euxinic conditions in the water column, with average (mean) values ranging from 5.29 to 6.02 µm and quite low standard deviation (SD) values ranging from 1.49 to 3.0. The remaining samples have shown slightly higher values of framboid diameter typical for upper dysoxic conditions, with average values (6.37 to 7.20 µm) and low standard deviation (SD) values (1.88 to 2.88). From the depth of 75.5 m till the shallowest part of the Jeleniów Claystone Formation, two samples have been examined and no framboids has been detected. Because secondary weathering should be excluded, the lack of framboids possibly indicates oxic conditions in the water column. Oxic conditions continue within the Wólka Formation based on the lack of framboids in the ZB 51.6 sample.

Źródło:

Contemporary Trends in Geoscience; 2014, 3, 1; 59-67
2299-8179

Pojawia się w:

Contemporary Trends in Geoscience

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 34.

Tytuł:

Surface chemistry and flotation properties of galena and pyrite particles in the presence of xanthate- monothiophosphate- thiocarbamate collectors

Autorzy:

Ercelik, Gokhan
Terzi, Mert
Kursun, Ilgin
Ozdemir, Orhan

Powiązania:

https://bibliotekanauki.pl/articles/24148622.pdf

Data publikacji:

2023

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
galena
zeta potential
bubble-particle attachment time
micro-flotation

Opis:

In this study, surface chemistry and flotation properties of the gold-bearing galena and pyrite minerals of Menderes region, Izmir, Turkey were investigated with the use of xanthate-thiocarbamate-monothiophosphate collectors. In this context, the micro-flotation experiments, the zeta potential, and bubble-particle attachment time measurements were conducted in the presence of Thiophosphate (Aero S-8045), Xanthate (SIBX), and Thiocarbamate (Aero float MX-505) collectors. In the case of micro-flotation experiments, the MX-505 exhibited higher flotation efficiency for both minerals compared to SIBX and S-8045 collectors. In the micro-flotation tests conducted on galena and pyrite, while the flotation recovery of 99.82% and 81.96% were obtained with MX-505, the flotation recovery of 89.64% and 62.50% were reached in the case of using SIBX. Furthermore, the S-8045 resulted in the flotation recovery s of 75.09% and 25.45% for galena and pyrite, respectively. In the case of zeta potential experiments as a function of pH, the galena mineral showed a negative charge between -17.22 to -41.42 mV at pH 5 – 11, no point of zero charge (pzc) was determined, and the pzc of pyrite was determined as pH≈8. The bubble-particle attachment time experiments performed in the presence of S-8045, SIBX, and MX-505 collectors indicated that the attachment efficiency was 100% in the presence of MX-505 at 12.5-75 g/Mg dosages and 1-1000 ms contact times. These results revealed that there was an extraordinarily strong interaction between the galena/pyrite and the air bubbles in the presence of MX-505. The results obtained within this study indicated that galena and pyrite minerals showed inherently less than 25% natural floatability which can only be enhanced under specific conditions. The results obtained within this study indicated that galena and pyrite minerals showed inherently low natural floatability which can only be enhanced under specific conditions. In the tests conducted on these minerals, galena mineral showed higher than %20 natural floatability compared to pyrite mineral, and collectors produced from thiocarbamates have shown greater effectiveness compared to xanthate and thiophosphate.

Źródło:

Physicochemical Problems of Mineral Processing; 2023, 59, 5; art. no. 167947
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 35.

Tytuł:

Ammonium chloride’s weakening effect on the copper activation of pyrite in flotation and the surface regulation mechanism behind it

Autorzy:

Zhang, Shengdong
Chen, Yumeng
Tong, Xiong
Xie, Xian
Lu, Yalin

Powiązania:

https://bibliotekanauki.pl/articles/110323.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
depression
cuprammonium solution
pH buffering property
flotation

Opis:

The traditional separation process of pyrite and marmatite is carried out under highly alkaline conditions. Therefore, a large amount of lime is demanded and the zinc recovery cannot be guaranteed. However, under weakly alkaline conditions, copper-activated pyrite has good floatability, which is difficult to separate from marmatite. In this paper, ammonium chloride (NH₄Cl) is used for depressing the flotation of copper-activated pyrite to achieve the separation of these two minerals under weakly alkaline environment. The flotation tests show that NH₄Cl can significantly reduce the floatability of pyrite in weakly alkaline conditions. The results of adsorption tests and X-ray photoelectron spectroscopy (XPS) analyses indicate that NH₄Cl can obviously change the composition of pyrite surface by increasing the content of iron/copper hydroxide and reducing the content of copper sulfides. Calculation of the solution composition demonstrates that the addition of NH₄Cl results in the occurrence of Cu(NH₃)n²⁺ and the pH buffering property. Based on these results, it can be concluded that the depression of NH₄Cl on copper activated pyrite is mainly derived from two aspects: 1) the pH buffering property of the conjugated acid-base pair (NH₄₊/NH₃) can impede the decline of OH- concentration, which results in more hydroxide adsorbed on pyrite; 2) NH₃ (aq) competes with the pyrite surface to consume Cu²⁺through complexation, which causes a reduction in the amount of copper sulfides formed on the pyrite surface.

Źródło:

Physicochemical Problems of Mineral Processing; 2019, 55, 5; 1070-1081
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 36.

Tytuł:

Improving recovery efficiency for pyrite from high sulfur gangue by collaborating vibration energy in fluidized bed

Autorzy:

Zhou, Chenyang
Fan, Xuchen
Dong, Liang
Duan, Chenlong
Zhao, Yuemin

Powiązania:

https://bibliotekanauki.pl/articles/110615.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

vibrated fluidized bed
pyrite recovery
density segregation
high sulfur gangue
dry beneficiation

Opis:

It is of great significance for economic development and environment protection to recover pyrite from high sulfur gangue in China. Due to problem of global water shortage, it is urgent to explore more efficient separation methods without consuming water in mineral processing field. This study has proposed an innovative method for pyrite recovery using vibration fluidized bed based on particle density difference. Detailed separation results depicted that sulfur content of -6+3 mm, -3+1 mm and -1+0.5 mm samples increased to ca. 37%, 33% and 27%. The highest comprehensive recovery rate reached ca. 72%. Compared with recent wet methods, separation results indicated that it was satisfied for pyrite recovery using vibrated fluidized bed. Thus, it is a feasible way for pyrite recovery from high sulfur gangue through the dry method of fluidized bed by collaborating vibration energy.

Źródło:

Physicochemical Problems of Mineral Processing; 2019, 55, 1; 70-81
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 37.

Tytuł:

Framboidy pirytowe jako wskaźniki paleośrodowiska
Pyrite framboids as paleoenvironmental indicators

Autorzy:

Zatoń, M.
Rakociński, M.
Marynowski, L.

Powiązania:

https://bibliotekanauki.pl/articles/2074589.pdf

Data publikacji:

2008

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

framboidy pirytowe
redoks
warunki środowiskowe oksyczne
warunki środowiskowe dysoksyczne
warunki środowiskowe euksyniczne
jura
dewon
Polska
pyrite framboids
redox
euxinia
anoxia
dysoxia
Jurassic
Devonian
Polska

Opis:

The problemof application of pyrite framboids in reconstructions of the redox conditions is presented. The characteristics of pyrite framboids, their origin and principles of application in paleoenvironmental interpretations are given. The pyrite framboid diameter distribution as indicators of redox conditions was presented on the examples of the Middle Jurassic (Upper Bajocian-Lower Bathonian) ore-bearing clays of the Polish Jura, and Upper Devonian (Middle and Upper Famennian) dark grey and black shales from Kowala (Holy Cross Mountains). It has been shown, that during the sedimentation of the ore-bearing clays, the pyrite framboids formed in the sediment, below the oxic water column; however, some episodic oscillation around the dysoxic conditions cannot be entirely excluded. During the sedimentation of the Middle Famennian dark grey shales, the redox conditions at the sea-floor oscillated around dysoxia. In both examples, the framboids are characterized by wide range of their diameters and the presence of large, >10 "my"m, framboids. On the contrary, the Upper Famennian black shales, representing the Hangenberg event, were deposited below the euxinic conditions in the water column. It is indicated by a high frequency of small-size framboids, far below 6 "my"m in diameter, and the lack of the large ones. The overlying shales, on the other hand, show the transition to more oxic conditions. The redox conditions interpreted above are in agreement with the independent biomarker analyses and paleontological observations.

Źródło:

Przegląd Geologiczny; 2008, 56, 2; 158-164
0033-2151

Pojawia się w:

Przegląd Geologiczny

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 38.

Tytuł:

The depression mechanism on pyrite in a low-alkaline system with combined depressants : Experiment, HSC, DFT and ToF–SIMS studies

Autorzy:

Li, Suqi
Yuan, Jiaqiao
Ding, Zhan
Li, Jie
Yu, Anmei
Wen, Shuming
Bai, Shaojun

Powiązania:

https://bibliotekanauki.pl/articles/24085821.pdf

Data publikacji:

2023

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
calcium hypochlorite
lime
depression
low alkaline system

Opis:

Depression of pyrite in a low-alkaline system has sparked soaring interests for the multi-metal sulfide minerals flotation recently. This study investigates effects of combined depressants (Ca(ClO)2 and CaO) on pyrite flotation with butyl xanthate (KBX). Micro-flotation experiments indicate that the addition of 200 mg/L combined depressants (a mass ratios of CaO to Ca(ClO) 2 of 2:3) and 1.0×10−3 mol/L KBX at pH 9.5 can effectively depresses the flotation of pyrite, and a minimum pyrite recovery rate of 12.5% is obtained. Basic thermodynamic evaluation results confirm the participation of Ca(ClO) 2 significantly decrease the negative Gibbs free energies of pyrite oxidation reaction. Besides, the calcium species (Ca(OH) 2, Ca2+ and Ca(Cl) 2) will spontaneously transform into CaCO3,and it is the ultimate dominant calcium species in the CO32- system. Density functional theory (DFT) results indicate that CaCO3 can chemically adsorb onto the pyrite surface with an adsorption energy of –671.13 kJ/mol. The O1 and Ca atoms mainly contribute to the bonding process and are responsible for the stable adsorption of CaCO3. ToF-SIMS results provide strong evidence that the combined depressants increase the amount of hydrophilic species and decrease dixanthogen adsorption onto the pyrite surface. The thickness of the whole formed hydrophilic species is approximately 50 nm. Semiquantitative amounts of hydrophilic species follow the order of hydroxy calcium>iron carbonyl>calcium carbonate. Overall, hydrophilic species repulse adsorption of dixanthogen and significantly reduce the flotation performance of pyrite.

Źródło:

Physicochemical Problems of Mineral Processing; 2023, 59, 3; art. no. 168454
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 39.

Tytuł:

An innovative flotation technology for the lime-depressed pyrite recovery from copper sulphide ore via acid mine drainage (AMD) activation

Autorzy:

Yuan, Jiaqiao
Ding, Zhan
Bi, Yunxiao
Li, Jie
Wen, Shuming
Bai, Shaojun

Powiązania:

https://bibliotekanauki.pl/articles/2175438.pdf

Data publikacji:

2022

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

copper sulfide ore
acid mine drainage (AMD)
lime-depressed-pyrite
activator
hydrophilic species

Opis:

In this study, an innovative flotation technology consisted of Cu differential flotation with high alkali lime and pyrite recovery with acid mine drainage (AMD) activation was investigated for the cleaner beneficiation of the copper sulfide ore. Flotation test results showed that H2SO4 -CuSO4 and AMD could effectively activate the pyrite flotation with SBX collector. Moreover, the recovery of S concentrate is increased by 5.33% in the AMD system. Adsorption amount results of SBX collector indicated that the hydrophilic species (Ca2+, CaOH+ and FeOOH) were formed on the pyrite surfaces in the high alkali lime craft (pH=11.3) and degraded the interaction between SBX and pyrite surfaces. AMD can effectively clear off the hydrophilic calcium species and the copper ions originated from the AMD absorb onto the pyrite surfaces, facilitating the SBX collector adsorption. Composition analysis results of tailings water confirmed that the tailing water obtained by the AMD flotation system was more desirable to be recycled in the Cu differential flotation due to its higher pH value (8.7). The present study provides a novel approach for the treatment of AMD, and has the vital practical significance for the emission reduction of AMD and the increase of beneficiation profits.

Źródło:

Physicochemical Problems of Mineral Processing; 2022, 58, 6; art. no. 152609
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 40.

Tytuł:

Skład chemiczny pirytu w mieszance wsadowej do pirometalurgicznego procesu otrzymywania cynku i ołowiu
Chemical composition of pyrite in the feed mixture into zinc and lead pirometallurgical process

Autorzy:

Adamczyk, Z.
Nowińska, K.

Powiązania:

https://bibliotekanauki.pl/articles/113403.pdf

Data publikacji:

2016

Wydawca:

STE GROUP

Tematy:

pirometalurgia
cynk
ołów
piryt
mieszanka wsadowa
środowisko hipergeniczne
pyrometallurgy
zinc
lead
pyrite
feed mixture
hypergenic environment

Opis:

Piryt jest jednym z głównych składników mineralnych mieszanki wsadowej stanowiącej surowiec do procesu ISP pirometalurgicznego otrzymywania cynku i ołowiu w Hucie Cynku „Miasteczko Śląskie” S.A. W pirycie zidentyfikowano, obok wrostków sfalerytu i galeny, pierwiastki towarzyszące (Ca, Mn, Se, As, Ag, Cu). Pierwiastki te mogą kumulować się w materiałach z poszczególnych węzłów technologicznych m.in. w pyłach. Emitowane wraz z pyłami składniki mineralne, ulegając rozkładowi w środowisku hipergenicznym, mogą uwalniać do tego środowiska, znajdujące się w nich pierwiastki towarzyszące.
Pyrite is one of the major mineral composition in feed mixture of ISP pyrometallurgical process of Zinc Plant “Miasteczko Śląskie” S.A. In piryte sphalerite and galena inclusions and accompanying elements were identified (Ca, Mn, Se, As, Ag, Cu). The accompanying elements may accumulate in the materials of ISP process, for example dust. The mineral components emitted with dust into environment, may decompose and release the accompanying elements into the hypergenic environment.

Źródło:

Systemy Wspomagania w Inżynierii Produkcji; 2016, 5 (17); 38-47
2391-9361

Pojawia się w:

Systemy Wspomagania w Inżynierii Produkcji

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 41.

Tytuł:

Pressure oxidation of pyrite-arsenopyrite refractory gold concentrate

Autorzy:

Rusanen, L.
Aromaa, J.
Forsen, O.

Powiązania:

https://bibliotekanauki.pl/articles/110051.pdf

Data publikacji:

2013

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

gold ore
hydrometallurgy
leaching
factorial design

Opis:

Refractory gold ores have poor gold recoveries with direct cyanide leaching. Typically the refractoriness is due to encapsulation of the gold particles inside the host mineral. To liberate gold for leaching the host mineral must be broken by mechanical or chemical means. The aim of this study was to study the effect of temperature, oxygen partial pressure and slurry density on pressure oxidation of pyrite-arsenopyrite gold concentrate. Batch oxidation tests in an autoclave were done using a factorial design. Different responses were measured and analysed to study effect of the three factors and oxidation kinet-ics. Generally, high slurry density required high temperature and oxygen partial pressure to reach com-plete oxidation. Oxidation kinetics at 225°C temperature, with 1050 kPa oxygen partial pressure and 15% slurry density was found to be fastest resulting in complete conversion of sulfides in 30 minutes. At 195°C, 700 kPa oxygen partial pressure and 10% slurry density, the oxidation kinetics for complete sul-fide conversion was about 60 minutes. Slurry densities above 10% had an adverse effect on the oxidation rate, when the temperature was below 225°C and oxygen partial pressure below 1050 kPa.

Źródło:

Physicochemical Problems of Mineral Processing; 2013, 49, 1; 101-109
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 42.

Tytuł:

Studies on magnetite and pyrite mineralization, and on their early Palaeozoic ocean-floor host-rocks from the Leszczyniec Unit (West Sudetes, Poland)

Autorzy:

Oberc-Dziedzic, T.
Mochnacka, K.
Mayer, W.
Pieczka, A.
Creaser, R. A.
Góralski, M.

Powiązania:

https://bibliotekanauki.pl/articles/191471.pdf

Data publikacji:

2011

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

magnetite and pyrite mineralization
metabasites
ocean-floor metamorphism
paragonite
Leszczyniec Unit
Sudetes
Polska

Opis:

The Leszczyniec Unit extends along the eastern margin of the Karkonosze-Izera Massif. It comprises the Early Palaeozoic, MORB-like Leszczyniec complex composed of metabasites, metagranites and metasedi- ments. The metabasites host magnetite mineralization encountered in Jarkowice, whereas near Wieściszowice village the pyrite deposit occurs in metasediments and metabasites. The common feature of both sites is the almost complete absence of the accompanying ore minerals. Basing on petrographic, mineralogical, geochemical and microstructural studies, it was found that the metabasic rocks, which host magnetite mineralization, were lava flows, whereas the protoliths of pyrite-bearing schists were basic and acid tuffites accompanied by ocean-floor basalts. The igneous rocks from the Leszczyniec Unit were subjected to the ocean-floor metamorphism, whereas the accompanying sediments were altered by hydrothermal fluids enriched in sulphur ions, which reacted with iron derived from the sediment and promoted crystallization of pyrite. The sources of hydrothermal fluids were adjacent magmatic centres. The estimated age ~480 Ma for pyrite (Re-Os method) is similar to the previously known ~500 Ma age of metabasites (U-Pb, zircon method) from the Leszczyniec Unit, which establishes a temporal link between pyrite accumulation and the ocean-floor environment. The rocks of the Leszczyniec Unit, first altered by the ocean-floor metamorphism and the hydrothermal fluids, were subsequently subjected to the regional metamorphism at 360–340 Ma and the two-stage deformations of various intensities, followed by the third stage of deformations which caused the reorientation of the regional foliation. The zones of ductile and brittle deformations connected with the second deformation event host the accumulations of magnetite formed at the expense of Fe-bearing rock-forming minerals or from iron supplied from adjacent sources. In the pyrite-bearing schists, mineral assemblages formed during the hydrothermal alteration have been subjected to recrystallization and were included into domains defining foliation and lineation, which formed during the first stage of deformation. Pyrite crystals were affected by both deformation stages. At the end of the second stage, the invasion of fluids led to the dissolution of pyrite crystals and to the filling of cracks in pyrite crystals with chalcopyrite and tennantite. This process was followed by the formation of quartz veins with minor amounts of ore minerals.

Źródło:

Annales Societatis Geologorum Poloniae; 2011, 81, No 2; 133-160
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 43.

Tytuł:

Research on Pyrite Occurrence and Properties in Talc Ore with the Aim of Its Removal
Badania występowania i właściwości pirytu w rudzie talku w celu jego usunięcia

Autorzy:

Hredzak, S.
Matik, M.
Lovas, M.
Briancin, J.
Stefusova, K.
Zubrik, A.

Powiązania:

https://bibliotekanauki.pl/articles/318677.pdf

Data publikacji:

2014

Wydawca:

Polskie Towarzystwo Przeróbki Kopalin

Tematy:

talc ore
pyrite
gravity concentration
XRD
ruda talku
piryt
wzbogacanie grawitacyjne

Opis:

The contribution deals with piryte occurrence in talc ore from the Geremska Paloma deposit (Eastern Slovakia). Firstly, an applicability of talc in various industrial branches such as paper and rubber is introduced. Major producers of talc in the world e.g. China, India and USA as well as the development of talc exploitation in Slovakia are also described. According to data about reserves of talc ore the Gemerska Poloma deposit can be considered as the most significant in the Europe. Pyrite is main harmful mineral and it occurs above all in talc nearby its contact zone with magnesite bodies. The sample of talc ore polluted by pyrite was assayed with the aim to pyrite liberation and characterization. A lumpy ore (5–20 mm) was crushed to a grain size below 5 mm and classified. The individual grain sizes were subjected to float-sink analyses in bromoforme. Obtained products were weighted and analysed. Selected products were studied using XRD. An optical observation of lumpy ore showed, that pyrite grains attain a size of 0.5–6 mm. As to crushed ore iron and sulphur concentrate in the grain size classes of 0.5–3 mm, above all in 1–2 mm. The highest mass yield of pyrite concentrate into heavy product was attained in a class of 1–2 mm, namely 15 %. This product contains 44.62 % S and 37.06 % Fe followed by 3.14 % Mg, 2.45 % SiO2 and 0.76 % Ca. The highest grade of pyrite concentrate using float-sink analysis was achieved in the case of grain size 0.5–1 mm at a mass yield of 8.35 %. It contains 45.52 % S and 38.18 Fe. Moreover, chemical analysis of pyrite concentrate prepared by hand-picking (50.90 % S, 43.10 % Fe) proved an abundance of cobalt (1218 ppm), manganese (340 ppm), nickel (175 ppm) and arsenic (119 ppm).
Praca ta opisuje występowanie pirytu w rudzie talku ze złoża Gemerska Poloma (wschodnia Słowacja). Po pierwsze, przedstawiono stosowanie talku w różnych gałęziach przemysłu, takich jak przemysł papierniczy i gumowy. Opisane zostały również: główni producenci talku na świecie tj. Chiny, Indie i USA, jak również rozwój eksploatacji talku na Słowacji. Według danych dotyczących zasobów rudy talku złoże Gemerska Poloma można uznać za najbardziej znaczące w Europie. Piryt jest głównym szkodliwym minerałem i występuje przede wszystkim w pobliżu talku w jego strefie kontaktu z organami magnezytowymi. Próbki rudy talku zanieczyszczonej pirytem badano w celu wyzwolenia i charakteryzacji pirytu. Grudkowata ruda (5-20mm) została zgnieciona do wielkości ziarna poniżej 5mm i sklasyfikowana. Poszczególne rozmiary ziarna poddano analizie unoszenia-tonięcia w bromoforme. Otrzymane produkty zważono i poddano analizie. Wybrane produkty badano stosując metodę XRD. Optyczna obserwacja grudkowatej rudy wykazała, że ziarna pirytu osiągają wielkość 0,5-6mm. W przypadku pokruszonej rudy żelazo i siarka koncentruje się w ziarnach o klasach wielkości 0,5-3mm, przede wszystkim w 1-2mm. Najwyższa wydajność masy koncentratu pirytu w ciężkim produkcie uzyskana została w klasie 1-2mm, to znaczy 15%. Produkt zawiera 44.62% 37.06% S i Fe, następnie 3,14% Mg, 2,45% SiO2 i 0,76% Ca. Najwyższy stopień czystości koncentratu pirytu, stosując analizę typu unoszenia-tonięcia został osiągnięty w przypadku wielkości ziarna 0,5-1mm, przy masowej wydajnością 8,35%. Zawiera 45,52% S i 38,18% Fe. Co więcej, analiza chemiczna koncentratu pirytu przygotowany przez zbiór ręczny (50,90% S, 43,10% Fe) wykazała obfitość kobaltu (1218ppm), manganu (340ppm), niklu (175ppm) i arsenu (119ppm).

Źródło:

Inżynieria Mineralna; 2014, R. 15, nr 2, 2; 23-28
1640-4920

Pojawia się w:

Inżynieria Mineralna

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 44.

Tytuł:

Mineralogy characteristics, stability conditions, and formation pathways of synthetic pyrrhotite formed by heating pyrite at 700℃
Charakterystyka mineralogiczna, warunki stabilności i ścieżki powstawania syntetycznego pirotynu utworzonego przez ogrzewanie pirytu w temperaturze 700℃

Autorzy:

Wang, Zhehao
Wang, Ling
He, Yuting
Duan, Jiongran
Fan, Bowen

Powiązania:

https://bibliotekanauki.pl/articles/2203296.pdf

Data publikacji:

2023

Wydawca:

Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN

Tematy:

synthetic pyrrhotite
pyrrhotite
pyrite
hematite
pirotyn syntetyczny
pirotyn
piryt
hematyt

Opis:

Pyrite is a sulfide mineral and is widely distributed in nature. Pyrite may transform into pyrrhotite when heated at high temperatures. In order to support processing engineering techniques and industrial applications of pyrite and pyrrhotite, it is necessary to investigate synthetic pyrrhotite, which is formed by heating pyrite in air, based on existing research. In this work, the mineralogical characteristics and stability conditions of synthetic pyrrhotite formed by heating pyrite at elevated temperatures were studied. The possible formation pathway was verified using a solid-phase reaction. X-ray-diffraction results revealed that synthetic pyrrhotite differs from natural pyrrhotite in the paragenetic association of minerals. Natural pyrrhotite and magnetite coexist in the natural pyrrhotite sample. Synthetic pyrrhotite formed by heating pyrite at 700℃ for 1 h has the paragenetic association with hematite and a small amount of pyrite and magnetite. All pyrrhotite samples were monoclinic pyrrhotite-4C (Fe7S8) and exhibit minimal differences in terms of lattice parameters. Synthetic pyrrhotite-4C was stable under 0.5–2 h of heating at 700℃ in air. It had the highest relative content by heating for 1 h. It was eventually transformed into hematite with heating periods exceeding 3 h, as was the case for pyrite and magnetite. In air, synthetic pyrrhotite-4C is mainly formed via two pathways: (1) pyrite → pyrrhotite-4C and (2) pyrite → magnetite → pyrrhotite-4C. Pathway (1) is more favorable than pathway (2). This transformation cannot be achieved by the reaction between hematite and sulfur.
Piryt jest minerałem siarczkowym szeroko rozpowszechnionym w przyrodzie. Piryt może przekształcić się w pirotyn podczas ogrzewania w wysokich temperaturach. W celu wsparcia technik inżynierii mineralnej i przemysłowego zastosowania pirytu i pirotynu, konieczne jest zbadanie syntetycznego pirotynu w oparciu o istniejące badania, który powstaje w wyniku ogrzewania pirytu w powietrzu. W pracy zbadano właściwości mineralogiczne i warunki trwałości syntetycznego pirotynu powstałego w wyniku ogrzewania pirytu w podwyższonej temperaturze. Możliwą ścieżkę powstawania zweryfikowano za pomocą reakcji w fazie stałej. Wyniki dyfrakcji rentgenowskiej ujawniły, że syntetyczny pirotyn różni się od naturalnego pirotynu w paragenetycznych asocjacjach minerałów. Naturalny pirotyn i magnetyt współistnieją w próbce naturalnego pirotynu. Syntetyczny pirotyn powstały w wyniku ogrzewania pirytu w temperaturze 700℃ przez 1 godz. wykazuje asocjację paragenetyczną z hematytem oraz niewielką ilością pirytu i magnetytu. Wszystkie próbki pirotynu były jednoskośnym pirotynem-4C (Fe7S8) i wykazują minimalne różnice pod względem parametrów sieci. Syntetyczny pirotyn-4C był stabilny w czasie 0,5–2 godzin ogrzewania w powietrzu w temperaturze 700℃. Najwyższą względną zawartość miał po ogrzewaniu przez 1 godzinę. Ostatecznie został przekształcony w hematyt z okresami ogrzewania przekraczającymi 3 godziny, podobnie jak w przypadku pirytu i magnetytu. W powietrzu syntetyczny pirotyn-4C powstaje głównie dwoma metodami: (1) piryt → pirotyn-4C i (2) piryt → magnetyt → pirotyn-4C. Ścieżka (1) jest korzystniejsza niż ścieżka (2). Tej przemiany nie można osiągnąć w reakcji hematytu z siarką.

Źródło:

Gospodarka Surowcami Mineralnymi; 2023, 39, 1; 23--34
0860-0953

Pojawia się w:

Gospodarka Surowcami Mineralnymi

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 45.

Tytuł:

Identyfikacja i możliwość przystosowania łupków powęglowych z pirytem do stosowania w budownictwie drogowy
Identification and adaptation of coaly shales with pyrite for use in road construction

Autorzy:

Duszyński, Andrzej
Jasiński, Wiktor
Jórdeczka, Łukasz
Pryga-Szulc, Aneta

Powiązania:

https://bibliotekanauki.pl/articles/2076068.pdf

Data publikacji:

2020

Wydawca:

Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy

Tematy:

łupki węglowe
piryt
agregat
adaptacja materiału
wał przeciwpowodziowy
wybudowana droga
coaly shale
pyrite
aggregate
material adaptation
embankment
built-way

Opis:

Coaly shale is a full-fledged aggregate for road construction, which can be obtained through proper control and processing, meeting the performance characteristics for the application in the construction of embankments. In Poland, from current pro¬duction and resources at landfills, coaly shale with a pyrite content above 1% is a great potential for road construction. It requires adaptation, including on eliminating the possibility of bacteria decomposing this pyrite or its neutralization using limestone materials. At the same time, taking into account the weaknesses of coaly shale landfills (in terms of self-ignition and decomposition), the type of coaly shale and pyrite raw material can be identified as ways of using aggregates from these raw materials for the construction of embankments in the appropriate construction technology.

Źródło:

Przegląd Geologiczny; 2020, 68, 9; 716--721
0033-2151

Pojawia się w:

Przegląd Geologiczny

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 46.

Tytuł:

Physico-chemical factors in flotation of Cu-Mo-Fe ores with seawater: a critical review

Autorzy:

Castro, S.

Powiązania:

https://bibliotekanauki.pl/articles/109447.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

pyrite
chalcopyrite
molybdenite
Seawater flotation
Metabisulfite

Opis:

This paper aims to provide a comprehensive review on the physico-chemical factors governing the flotation of Cu-Mo-Fe sulfide ores in seawater, which is different from NaCl or KCl solutions because it contains hydrolysable ions such as Mg²⁺, Ca²⁺, HCO3-, CO3^2-, etc., which can precipitate with lime as hydroxides, Ca, and Mg insoluble salts. Under pH 9.0 Mg²⁺ ions do not depress molybdenite. However, over the critical pH of precipitation of Mg(OH)2 (pH>10.0), molybdenite is strongly depressed in seawater. This detrimental effect on molybdenite discards the use of lime to depress pyrite in Cu-Mo-Fe ores floated in seawater. In plant practice, the use of sodium metabisulfite (MBS) has replaced lime as a pyrite depressant. It works at pH 6.5-7.0 where the natural floatability of molybdenite is enhanced. Consequently, pH control in rougher and cleaning circuits, and the use of MBS to depress pyrite, have allowed the successful use of non-desalinated seawater in flotation of Cu-Mo-Fe sulfide ores at industrial scale.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 4; 1223-1236
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 47.

Tytuł:

Relationships between development of organic− rich shallow shelf facies and variation in isotopic composition of pyrite (Middle Triassic, Spitsbergen)

Autorzy:

Karcz, Przemysław

Powiązania:

https://bibliotekanauki.pl/articles/2051601.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

Arctic
Svalbard
Bravaisberget Formation
sulphur isotopes
organic carbon

Źródło:

Polish Polar Research; 2010, 3; 239-254
0138-0338
2081-8262

Pojawia się w:

Polish Polar Research

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 48.

Tytuł:

Pyrite framboids in pyritized Radiolarian skeletons (Mid-Cretaceous of the Pieniny Klippen Belt, Western Carpathians, Poland)

Autorzy:

Szczepanik, P.
Sawłowicz, Z.
Bąk, M.

Powiązania:

https://bibliotekanauki.pl/articles/191646.pdf

Data publikacji:

2004

Wydawca:

Polskie Towarzystwo Geologiczne

Tematy:

radiolaria
pyritization
framboids
Cretaceous
Pieniny Klippen Belt

Opis:

Well preserved pyritized radiolarian skeletons have been found within the grey-green Mid-Cretaceous (Upper Cenomanian) shales in the Pieniny Klippen Belt (Carpathians, Poland). The skeletons contain numerous pyrite framboids in different positions, in channels and inside the abdomen of cryptothoracic forms, but their genetic context is not known. They were formed as a result of the reaction between dissolved iron and sulphide originated from the bacterial sulphate reduction. Two sources of organic matter, "post mortem" in situ decaying organic matter of radiolaria and disseminated organic matter from the surrounding sediment could be available for this process. Pyrite found in the radiolarians probably originates from different processes. It is suggested that pyritization of the radiolarian skeletons took place in the water column whereas pyrite framboids in the skeleton's free spaces could have been formed later during the diagenesis of the sediment. However, their simultaneous formation in the water column or in the sediment cannot be excluded.

Źródło:

Annales Societatis Geologorum Poloniae; 2004, 74, No 1; 35-41
0208-9068

Pojawia się w:

Annales Societatis Geologorum Poloniae

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 49.

Tytuł:

Interaction between sphalerite and pyrite and its effect on surface oxidation of sphalerite

Autorzy:

Yang, B.
Xie, X.
Tong, X.
Lan, Z.
Cui, Y.

Powiązania:

https://bibliotekanauki.pl/articles/109553.pdf

Data publikacji:

2018

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

sphalerite
surface oxidation
minerals interaction
DFT

Opis:

The interaction between sphalerite and pyrite was investigated by dissolution test, X-ray photoelectron spectroscopy (XPS), zeta potential measurement and density functional theory (DFT) calculation. Dissolution tests indicated that sphalerite dissolution was promoted due to the galvanic interaction between sphalerite and pyrite. The Zn2+ ion concentration increased with increasing pyrite content and dissolved time. XPS analysis results demonstrated that a new oxidation product was formed on the sphalerite surface in the presence of pyrite in a pulp. Zeta potential measurements showed that the isoelectric point of sphalerite increased from 3.3 to 5.4 due to galvanic interaction. DFT calculation results suggested that electron transfer from sphalerite to pyrite occurred when they contacted. The Zn 4s and S 3p states of sphalerite lost electrons. The Fe 4p and 4s of pyrite states obtained electrons, and Fe 3d and S 3s states lost a small number of electrons. The surface oxidation of sphalerite was promoted due to the interaction with pyrite, and the collectorless floatability of sphalerite decreased.

Źródło:

Physicochemical Problems of Mineral Processing; 2018, 54, 2; 311-320
1643-1049
2084-4735

Pojawia się w:

Physicochemical Problems of Mineral Processing

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 50.

Tytuł:

Influence of the presence of carbon dioxide on chemical composition of water in contact with mining waste

Autorzy:

Cempa-Balewicz, M.

Powiązania:

https://bibliotekanauki.pl/articles/91956.pdf

Data publikacji:

2015

Wydawca:

Główny Instytut Górnictwa

Tematy:

odpady pogórnicze
piryt
ditlenek węgla
mining waste
pyrite
carbon dioxide

Opis:

Nowadays post mining areas are often reclaimed and used housing areas, sports areas and recreational areas. Mining waste weathering is a significant factor influencing the condition of the surrounding water and soil environment. It is necessary then to evaluate susceptibility of the waste to weathering in given conditions and predict the rate of the processes. The paper presents initial results of an experimental study evaluating the influence of the presence of CO2 on the composition of leachate obtained when mining waste is exposed to water. The results of the experiments confirm the importance of the oxidation of pyrite and dissolution of carbonate minerals in changing the pH of water interacting with the waste.

Źródło:

Journal of Sustainable Mining; 2015, 14, 1; 38-45
2300-1364
2300-3960

Pojawia się w:

Journal of Sustainable Mining

Dostawca treści:

Biblioteka Nauki

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