Sphalerite Concentrations Research Articles

Surface Modification of Galena Concentrate, Sphalerite Concentrate, and Silica by the Bacterium Citrobacter sp. and Its Application to Green Flotation of Complex Pb–Zn Ores

Surface Modification of Galena Concentrate, Sphalerite Concentrate, and Silica by the Bacterium Citrobacter sp. and Its Application to Green Flotation of Complex Pb–Zn Ores

Leaching of Indium from Indium-and Iron-Bearing Sphalerite Concentrate in Sulfuric Acid–Ferric Sulfate Solution

Abstract Leaching of indium from an indium-and iron-bearing sphalerite concentrate in sulfuric acid– ferric sulfate solution was examined. The effects of various parameters were studied. Increases in the stirring speed, temperature, ferric ion and sulfuric acid concentrations, and decreases in the particle size, enhanced the indium leaching rate. Scanning electron microscopy/energy-dispersive X-ray spectroscopy and X-ray diffraction analyses of the unreacted and reacted sphalerite concentrate particles showed that elemental sulfur was formed and precipitated at the particle surfaces. The results show that dissolution was controlled by a mixed-control process. In the initial stage, the dissolution kinetics was chemically controlled. When more elemental sulfur was present on the particle surfaces, the dissolution kinetics was controlled by mass transfer though the sulfur layer. The activation energy of the chemically controlled step was 33.9 kJ/mol. The reaction orders with respect to the initial sulfuric acid and ferric ion concentrations were approximately 0.74 and 0.60, respectively.

Adaptation of Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans strains on sphalerite concentrate from mining waste

One of the main characteristics of the microorganisms used in the leaching process is their capacity to adapt to aggressive environments, characterized by a notable presence of heavy metals. In this study the adaptation of the strains Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans was evaluated on a sphalerite concentrate from mining waste. In the adaptation tests, the energy source (ferrous sulphate) was gradually replaced by percentages of mineral pulp, ending with subcultures without the addition of an external energy source. The results show that the strains A. ferrooxidans and A. thiooxidans are more resistant to high concentrations of sphalerite, compared to the strain of L. ferrooxidans, since, in the case of this strain, it was necessary to repeat some tests (8% of pulp), since a deficient development was evident. This was associated with factors such as the decrease of the Fe+2 energy source, the increase of the pulp density, the accumulation of toxic metals and secondary products of the dissolution of minerals and the increase of the pH.

VARIABILITY OF ORE MINERALIZATION IN THE NORTH-WEST-TRENDING EXTENSIONOF THE LUBIN–SIEROSZOWICE DEPOSIT

The Polish Geological Institute – NRI has conducted investigations of the Kupferschiefer series since 1957, when the giant sediment-hosted stratiform Cu-Ag ore deposit was discovered in the central part of the Fore-Sudetic Monocline. Until 1991, a number of drilling programs were completed by PGI-NRI and later research has been focusing mainly on cooperation with oil and gas industry and their core material. Over the last few years, thanks to systematic examination of the drill holes located in the north-western extension, many prospective areas have been recognized and delineated. These prospects are located between Lubin-Sieroszowice deposit and the eastern part of the Zielona Góra oxidized field. In the Kożuchów area, the lower part of Zechstein copper-bearing series contain only relict sulphide mineralization accompanied by iron oxides while reduced rocks with metal sulphides occur in the uppermost part of Zechstein Limestone or at the base of Lower Anhydrite. Grochowice area, where reduced facies prevail in copper-bearing series, is characterized by the predomination of rich Cu-Ag mineralization proximaly to oxidized area. The western part of studied area is dominated by Cu-S type sulphides (chalcocite, digenite, covellite) whereas the eastern part is represented by Cu-Fe-S type minerals (bornite, chalcopyrite) with high galena and sphalerite concentrations. The spatial variability of sulphide mineralization with respect to the oxidized rocks indicates that Bytom Odrzański deposit extends in the north-west direction, continuing in the form of a copper belt along the eastern border of the oxidized area. An extensive deep exploration drilling program is implemented to verify the resource potential within predicted copper belt.

Indium mineralisation in SW England: Host parageneses and mineralogical relations

The SW England ore region contains significant amounts of indium (In) in Early Permian granite-related skarn and lode parageneses and, to a lesser extent, Triassic epithermal “crosscourse” veins. Ore parageneses that predate granite emplacement (Devonian and Lower Carboniferous sedimentary exhalative and vein parageneses) are largely devoid of In. Cadmium (Cd) and gallium (Ga) occur widely in all sulphide-bearing parageneses across the region with sphalerite concentrations locally reaching 1.74wt% Cd and 1750ppmGa.Indium displays a strong affinity to sulphide-bearing magmatic-hydrothermal parageneses. It occurs in silicate-sulphide skarns, polymetallic sulphide lodes and sulphide-bearing portions of greisen-bordered sheeted vein systems and quartz-tourmaline lodes across the region. Magnetite-silicate skarns and quartz-tourmaline lodes that are devoid of sulphide, in contrast, were comparatively unfavourable for In precipitation. The highest In concentrations are found in mineral lodes associated with the Carnmenellis and St Agnes granites, which are the districts that had the highest historical production of Sn. Total In concentrations in these areas locally exceed 430ppm, while concentrations elsewhere are systematically below 200ppm.The principal In hosts are chalcopyrite, sphalerite and stannite group minerals with local concentrations within cassiterite and tennantite. Surprisingly, chalcopyrite accounts for the majority of the In budget throughout the region, although concentrations are highest in sphalerite and stannite group minerals. Sphalerite locally contains up to 1.42wt% In, chalcopyrite has up to 2200ppm and stannite group minerals up to 6800ppm. No In was detected in löllingite, arsenopyrite, rutile, haematite, magnetite, tourmaline, biotite, chlorite, galena, bornite, chalcocite or pyrrhotite. Scattered concentrations in pyrite relate to impurities rather than incorporation by solid solution. Roquesite and possibly dzhalindite or native In formed locally where In-bearing chalcopyrite or sphalerite has been replaced by bornite and quartz. The In partitioning between sphalerite and chalcopyrite varies broadly between 1:1 and 10:1.Sporadic In was included in Triassic crosscourse veins as a result of interactions between migrating CaCl2-rich basinal brines and earlier formed granite-related parageneses. The interactions involved at least two distinct components: 1) Incorporation of clasts of magmatic-hydrothermal veins in crosscourse veins during faulting, and 2) Dissolution and re-precipitation of magmatic-hydrothermal vein minerals in crosscourse fluids. Local concentrations reach 140ppm In.The magmatic-hydrothermal parageneses in SW England are comparable to the South China Tin Belt, Mount Pleasant, as well as Erzgebirge/Krušné Hory. Magmatic-hydrothermal fluids associated with peraluminous granites have developed a variety of skarn, greisen, lode and veins parageneses by interactions with their host rocks and contained fluids. Crosscourse epithermal mineralisation occurred as In was transported by CaCl2-rich basinal brines in a similar manner as In-bearing veins in the West Shropshire ore field.

Kinetics and Modeling of Chemical Leaching of Sphalerite Concentrate Using Ferric Iron in a Redox-controlled Reactor

This work presents a study for chemical leaching of sphalerite concentrate under various constant Fe3+ concentrations and redox potential conditions. The effects of Fe3+ concentration and redox potential on chemical leaching of sphalerite were investigated. The shrinking core model was applied to analyze the experimental results. It was found that both the Fe3+ concentration and the redox potential controlled the chemical leaching rate of sphalerite. A new kinetic model was developed, in which the chemical leaching rate of sphalerite was proportional to Fe3+ concentration and Fe3+/Fe2+ ratio. All the model parameters were evaluated from the experimental data. The model predictions fit well with the experimental observed values.

Leaching Behaviour of Metals from a Sphalerite Concentrate in Sulfuric Acid-Oxygen System

Leaching behaviors of zinc, copper, indium and iron from a sphalerite concentrate in sulfuric acid-oxygen system has been investigated in the present paper. Various parameters were studied including particle size, concentration of sulfuric acid, partial pressure of oxygen, leaching temperature, and leaching time. The experimental data indicated that under the typical plant conditions employed up to 99% zinc , 85% copper and 90% indium extraction were achieved. The mineralogical analysis of the residue showed that the main minerals are elemental sulphur, unreacted pyrite and quartz, the amount of sulphide sulphur oxidized to sulfur during leaching is 81%. This process provides an effective way for the extraction of zinc, copper and indium from sphalerite concentrate.

Preparation and Characterization of Surface Modification of Sphalerite Concentrate with Sodium Lignosulfonate

In order to prevent sphalerite particles from coming together in leaching solution, and to reduce the loss of organic solvent, the surface modification of sphalerite concentrate with sodium lignosulfonate was investigated. The modified sphalerite concentrate particles were characterized by dispersion experiments, determination of adsorption rate of oil, determination of contact angle, FT-IR spectra and X-ray photoelectron spectra. The results showed that the modified sphalerite concentrate particles exhibited good dispersibility in water. The sedimentation volume reduced from 0.85 ml•g-1 to 0.61 ml•g-1. The adsorption rate of oil reduced from 0.15 ml•g-1 to 0.06 ml•g-1. The contact angle between sphalerite concentrate particles and water changed from 86.9˚ before modification to 32.7˚ after modification with sodium lignosulfonate. The checking results of FT-IR and XPS spectra indicated that some modification regents were coated on the particle surface. The modifier combined to sphalerite concentrate particle surface through the chemical bond, resulting in the comprehensive stability action of static and steric effect.

Reactive flow models of the Anarraaq Zn–Pb–Ag deposit, Red Dog district, Alaska

The Red Dog ore deposit district in the Brooks Range of northern Alaska is host to several high-grade, shale-hosted Zn + Pb deposits. Due to the complex history and deformation of these ore deposits, the geological and hydrological conditions at the time of formation are poorly understood. Using geological observations and fluid inclusion data as constraints, numerical heat and fluid flow simulations of the Anarraaq ore deposit environment and coupled reactive flow simulations of a section of the ore body were conducted to gain more insight into the conditions of ore body formation. Results suggest that the ore body and associated base metal zonation may have formed by the mixing of oxidized, saline, metal-bearing hydrothermal fluids (<200°C) with reducing, HS-rich pore fluids within radiolarite-rich host rocks. Sphalerite and galena concentrations and base metal sulfide distribution are primarily controlled by the nature of the pore fluids, i.e., the extent and duration of the HS− source. Forward modeling results also predict the distribution of pyrite and quartz in agreement with field observations and indicate a reaction front moving from the initial mixing interface into the radiolarite rocks. Heuristic mass calculations suggest that ore grades and base metal accumulation comparable to those found in the field (18% Zn, 5% Pb) are predicted to be reached after about 0.3 My for initial conditions (30 ppm Zn, 3 ppm Pb; 20% deposition efficiency).

Leaching of zinc sulfide concentrate from the ganesh-himal deposit of nepal

The leaching of zinc concentrate obtained from the zinc ore located in the Ganesh-Himal region of Nepal has been carried out in the presence of ammonium persulfate (APS) as an oxidant. Leaching variables such as time, temperature, acid, and oxidant concentration, E h , and particle size of sphalerite concentrate were studied to optimize the condition and to understand the mechanism of the reaction. The zinc extraction increased up to a temperature of 333 K and a further rise in the temperature to 343 K resulted in lowering of metal extraction. A decrease in particle size and increase in oxidant concentration enhanced the dissolution rate of zinc. The leaching data best fitted to the mixed controlled kinetic model. An activation energy of 43 kJ/mol was obtained for the dissolution of zinc in the temperature range 303 to 333 K with APS. The leaching mechanism was further established by characterizing the original concentrate and the leach residue by X-ray diffraction (XRD) phase identification and scanning electron microscopy (SEM) studies.

Sphalerite concentrations in Mid-Continent Pennsylvanian black shales of Missouri and Kansas

Sphalerite concentrations in Mid-Continent Pennsylvanian black shales of Missouri and Kansas

Prospection mini�re dans la r�gion Friuli-Venezia Giulia (Alpes Orientales)

Mineralogical alluvial prospecting search for base metals have been carried out from 1968 to 1970 in the Friuli — Venezia Giulia region. The Carnia, a part of this region, was well known from ancient times as an important mining district. Numerous anomalies of the content of some elements and minerals in river sands have been recognized by means of the above mentioned searches. This indicates that important and till now unknown ore concentrations are possible in this region. In fact three new sphalerite and/or galena concentrations and one fluorite concentration in association with As-sulphides have already been discovered during a partial development of these surveys. In the present work the advantages of alluvial prospecting in mining searches are remarked. Moreover method and application of mineralogical alluvial prospecting are described. In the last paragraph the steps which allowed the discovering of the new metal concentrations are reported in detail. The discovered concentrations are shortly analyzed. Strict aim of this note is to indicate the value and scientific importance of the described method.

Les breches sedimentaires zinciferes du Sinemurien du Lot [with discussion

Abstract Near Figeac in Lot, France, sphalerite concentrations are associated with sedimentary breccias occurring locally in lower Sinemurian (Jurassic) deposits. The breccias are considered penecontemporaneous deposits formed as a result of slumping of submarine talus slopes. The plateau facies on the east is replaced westward by a basinal facies, indicating sliding of the slump material from east to west. The degree of mineralization is directly proportional to the extent of slumping.

Investigation of the solubility of low volatility substance in high pressure steam by radio isotopes

The SW England ore region contains significant amounts of indium (In) in Early Permian granite-related skarn and lode parageneses and, to a lesser extent, Triassic epithermal “crosscourse” veins. Ore parageneses that predate granite emplacement (Devonian and Lower Carboniferous sedimentary exhalative and vein parageneses) are largely devoid of In. Cadmium (Cd) and gallium (Ga) occur widely in all sulphide-bearing parageneses across the region with sphalerite concentrations locally reaching 1.74 wt% Cd and 1750 ppm Ga.Indium displays a strong affinity to sulphide-bearing magmatic-hydrothermal parageneses. It occurs in silicate-sulphide skarns, polymetallic sulphide lodes and sulphide-bearing portions of greisen-bordered sheeted vein systems and quartz-tourmaline lodes across the region. Magnetite-silicate skarns and quartz-tourmaline lodes that are devoid of sulphide, in contrast, were comparatively unfavourable for In precipitation. The highest In concentrations are found in mineral lodes associated with the Carnmenellis and St Agnes granites, which are the districts that had the highest historical production of Sn. Total In concentrations in these areas locally exceed 430 ppm, while concentrations elsewhere are systematically below 200 ppm.The principal In hosts are chalcopyrite, sphalerite and stannite group minerals with local concentrations within cassiterite and tennantite. Surprisingly, chalcopyrite accounts for the majority of the In budget throughout the region, although concentrations are highest in sphalerite and stannite group minerals. Sphalerite locally contains up to 1.42 wt% In, chalcopyrite has up to 2200 ppm and stannite group minerals up to 6800 ppm. No In was detected in löllingite, arsenopyrite, rutile, haematite, magnetite, tourmaline, biotite, chlorite, galena, bornite, chalcocite or pyrrhotite. Scattered concentrations in pyrite relate to impurities rather than incorporation by solid solution. Roquesite and possibly dzhalindite or native In formed locally where In-bearing chalcopyrite or sphalerite has been replaced by bornite and quartz. The In partitioning between sphalerite and chalcopyrite varies broadly between 1:1 and 10:1.Sporadic In was included in Triassic crosscourse veins as a result of interactions between migrating CaCl2-rich basinal brines and earlier formed granite-related parageneses. The interactions involved at least two distinct components: 1) Incorporation of clasts of magmatic-hydrothermal veins in crosscourse veins during faulting, and 2) Dissolution and re-precipitation of magmatic-hydrothermal vein minerals in crosscourse fluids. Local concentrations reach 140 ppm In.The magmatic-hydrothermal parageneses in SW England are comparable to the South China Tin Belt, Mount Pleasant, as well as Erzgebirge/Krušné Hory. Magmatic-hydrothermal fluids associated with peraluminous granites have developed a variety of skarn, greisen, lode and veins parageneses by interactions with their host rocks and contained fluids. Crosscourse epithermal mineralisation occurred as In was transported by CaCl2-rich basinal brines in a similar manner as In-bearing veins in the West Shropshire ore field.