Inverse gas chromatography has great potential in allowing an enhanced understanding of mineral surfaces, and the interactions between particles and air and water in mineral processing separations, ...such as flotation.
Two minerals of different degrees of natural hydrophobicity were investigated, namely galena and quartz. The surface energy was determined as a function of surface area, with the quartz sample displaying a higher work of adhesion, implying a higher degree of hydrophilicity. This was then compared to microflotation experiments. The higher work of adhesion to water for the quartz than galena (114.54mJm−2 compared to 101.71mJm−2 @ 5% coverage; 86.78mJm−2 compared to 71.69mJm−2 @ 38% coverage) was related to a lower recovery of quartz (6.94%) than galena (27.63%) through collectorless flotation.
This work shows the potential for using inverse gas chromatography in understanding mineral flotation. As can be seen from the figure, quartz has a higher work of adhesion to water than galena does, and this is borne out in microflotation tests. Display omitted
•Surface energy of galena and quartz was determined as a function of surface area.•Dispersive and specific components are used to calculate work of adhesion to water.•Work of adhesion to water was calculated and compared to a microflotation experiment.•iGC shows to be a useful tool to measure flotation-related properties of minerals.
A new hydrometallurgical leaching process, which dissolves lead concentrates with acidic ferric methanesulfonate solution, was proposed and investigated. The leaching kinetics of galena-containing ...concentrate from Red Dog Mine (Teck) was studied with respect to variables such as stirring speed, temperature, concentrations of free acid and ferric ions as well as particle size. It was found that stirring speed and acid concentration had no influence on the leaching rate, while increasing temperature moderately increased the rate. The leaching data best fitted the product-layer diffusion control mechanism based on the shrinking core model with an apparent activation energy value 36.15kJ/mol. The apparent reaction constant for the mean value of particle size and the reaction order for initial ferric concentration were very close to the theoretical values of 2 and 1, respectively.
•Ferric methane sulfonate is very suitable to treat galena concentrates.•Temperature has a pronounced effect on the dissolution rate of galena.•The dissolution can be very fast and completed in high temperature range.•The proton and ferric concentrations have very weak effects on the kinetics.•The kinetic process is controlled by product-layer diffusion.
Increased human health risk associated with groundwater contamination from potential carbon dioxide (CO2) leakage into a potable aquifer is predicted by conducting a joint uncertainty and variability ...(JUV) risk assessment. The approach presented here explicitly incorporates heterogeneous flow and geochemical reactive transport in an efficient manner and is used to evaluate how differences in representation of subsurface physical heterogeneity and geochemical reactions change the calculated risk for the same hypothetical aquifer scenario where a CO2 leak induces increased lead (Pb2+) concentrations through dissolution of galena (PbS). A nested Monte Carlo approach was used to take Pb2+ concentrations at a well from an ensemble of numerical reactive transport simulations (uncertainty) and sample within a population of potentially exposed individuals (variability) to calculate risk as a function of both uncertainty and variability. Pb2+ concentrations at the well were determined with numerical reactive transport simulation ensembles using a streamline technique in a heterogeneous 3D aquifer. Three ensembles with variances of log hydraulic conductivity (σ2 lnK) of 1, 3.61, and 16 were simulated. Under the conditions simulated, calculated risk is shown to be a function of the strength of subsurface heterogeneity, σ2 lnK and the choice between calculating Pb2+ concentrations in groundwater using equilibrium with galena and kinetic mineral reaction rates. Calculated risk increased with an increase in σ2 lnK of 1 to 3.61, but decreased when σ2 lnK was increased from 3.61 to 16 for all but the highest percentiles of uncertainty. Using a Pb2+ concentration in equilibrium with galena under CO2 leakage conditions (PCO2 = 30 bar) resulted in lower estimated risk than the simulations where Pb2+ concentrations were calculated using kinetic mass transfer reaction rates for galena dissolution and precipitation. This study highlights the importance of understanding both hydrologic and geochemical conditions when numerical simulations are used to perform quantitative risk calculations.
Balcılar (Çanakkale) barit-galenit cevherleşmesi, Biga yarımadasındaki damar tipi kurşun-çinko-barit yataklarının tipik örneklerinden birisidir. İnceleme alanındaki litolojik birimler; Eosen Akçaalan ...andeziti, Oligosen Adadağı piroklastikleri, Miyosen Dededağ dasiti, Pliyo-kuvaterner Karaömerler bazaltı ve Kuvaterner aluvyonlar olarak ayırtlanmıştır. Barit-galenit damarları andezitler içerisindeki faylar boyunca oluşmuşlardır. Barit, kuvars ve galenit ana mineraller olup, bu minerallere az miktarda sfalerit, pirit, kalkopirit, kovellin ve markazit eşlik etmektedir. Baritler erken evrede iri-taneli yarı özşekilli-özşekilli kristaller (barit I) ve geç evrede kaba kristallerle girift küçük çubuksu kristaller (barit II) biçiminde iki-evreli mineralizasyonla gelişmiştir. Kuvars küçük barit kristalleriyle birlikte geç evrede oluşmuştur. Galenit, sfalerit, kalkopirit, pirit, markazit ve kovellin geç evre ürünleri olup, önceki oluşan barit kristalleri içerisindeki boşluk zonları boyunca oluşmuşlardır. Sülfür izotop bulguları galenitteki sülfürün bakteriyel veya inorganik sülfattan (SO4=) indirgenmiş veya izotopik olarak hafif S-kökenle etkileşimi göstermektedir. Barit-H2S ve galenit-H2S ayrımlaşma faktörlerinden itibaren hesaplanan δ34SH2S değerleri, sıcaklık koşullarının 200-300 °C arasında olduğunu göstermiştir. Baritlerin güncel okyanus veya Eosen deniz suyu bileşiminden daha düşük δ34S değerleri, hidrotermal sıvıların magmatik yan kayaçlarla etkileşiminden kaynaklandığı biçiminde değerlendirilmiştir.
Balcılar (Çanakkale) barit-galenit cevherleşmesi, Biga yarımadasındaki damar tipi kurşun-çinko-barit yataklarının tipik örneklerinden birisidir. İnceleme alanındaki litolojik birimler; Eosen Akçaalan ...andeziti, Oligosen Adadağı piroklastikleri, Miyosen Dededağ dasiti, Pliyo-kuvaterner Karaömerler bazaltı ve Kuvaterner aluvyonlar olarak ayırtlanmıştır. Barit-galenit damarları andezitler içerisindeki faylar boyunca oluşmuşlardır. Barit, kuvars ve galenit ana mineraller olup, bu minerallere az miktarda sfalerit, pirit, kalkopirit, kovellin ve markazit eşlik etmektedir. Baritler erken evrede iri-taneli yarı özşekilli-özşekilli kristaller (barit I) ve geç evrede kaba kristallerle girift küçük çubuksu kristaller (barit II) biçiminde iki-evreli mineralizasyonla gelişmiştir. Kuvars küçük barit kristalleriyle birlikte geç evrede oluşmuştur. Galenit, sfalerit, kalkopirit, pirit, markazit ve kovellin geç evre ürünleri olup, önceki oluşan barit kristalleri içerisindeki boşluk zonları boyunca oluşmuşlardır. Sülfür izotop bulguları galenitteki sülfürün bakteriyel veya inorganik sülfattan (SO4=) indirgenmiş veya izotopik olarak hafif S-kökenle etkileşimi göstermektedir. Barit-H2S ve galenit-H2S ayrımlaşma faktörlerinden itibaren hesaplanan δ34SH2S değerleri, sıcaklık koşullarının 200-300 °C arasında olduğunu göstermiştir. Baritlerin güncel okyanus veya Eosen deniz suyu bileşiminden daha düşük δ34S değerleri, hidrotermal sıvıların magmatik yan kayaçlarla etkileşiminden kaynaklandığı biçiminde değerlendirilmiştir.
Balcılar (Çanakkale) barit-galenit cevherleşmesi, Biga yarımadasındaki damar tipi kurşun-çinko-barit yataklarının tipik örneklerinden birisidir. İnceleme alanındaki litolojik birimler; Eosen Akçaalan ...andeziti, Oligosen Adadağı piroklastikleri, Miyosen Dededağ dasiti, Pliyo-kuvaterner Karaömerler bazaltı ve Kuvaterner aluvyonlar olarak ayırtlanmıştır. Barit-galenit damarları andezitler içerisindeki faylar boyunca oluşmuşlardır. Barit, kuvars ve galenit ana mineraller olup, bu minerallere az miktarda sfalerit, pirit, kalkopirit, kovellin ve markazit eşlik etmektedir. Baritler erken evrede iri-taneli yarı özşekilli-özşekilli kristaller (barit I) ve geç evrede kaba kristallerle girift küçük çubuksu kristaller (barit II) biçiminde iki-evreli mineralizasyonla gelişmiştir. Kuvars küçük barit kristalleriyle birlikte geç evrede oluşmuştur. Galenit, sfalerit, kalkopirit, pirit, markazit ve kovellin geç evre ürünleri olup, önceki oluşan barit kristalleri içerisindeki boşluk zonları boyunca oluşmuşlardır. Sülfür izotop bulguları galenitteki sülfürün bakteriyel veya inorganik sülfattan (SO4=) indirgenmiş veya izotopik olarak hafif S-kökenle etkileşimi göstermektedir. Barit-H2S ve galenit-H2S ayrımlaşma faktörlerinden itibaren hesaplanan δ34SH2S değerleri, sıcaklık koşullarının 200-300 °C arasında olduğunu göstermiştir. Baritlerin güncel okyanus veya Eosen deniz suyu bileşiminden daha düşük δ34S değerleri, hidrotermal sıvıların magmatik yan kayaçlarla etkileşiminden kaynaklandığı biçiminde değerlendirilmiştir.
The Balcılar (Çanakkale) barite-galena mineralization is a typical example of the vein type barite-lead-zinc deposits in the Biga Peninsula. The lithologic units in the study area are Akçaalan ...andesite, Eocene, Adadağı pyroclastics, Oligocene, Dededağ dacite, Miocene, Karaömerler basalt, Plio-Quaternary and alluvium Quaternary. Barite-galena veins occurred along the faults developed within the andesites. Barite, quartz and galena are main minerals and are accompanied by minor amounts of sphalerite, pyrite, chalcopyrite, covellite and marcasite. The earliest barite (barite I) occurs as coarse-grained subhedral-euhedral crystals and the later (barite II) as small tabular crystals in between the earlier coarse crystals. Quartz occurs as fine-grained crystals with the later small barite crystals. Galena, sphalerite, chalcopyrite, pyrite, marcasite and covellite occur open spaces within the earlier barite (barite I) crystals. Sulfur isotopes indicate that in galena the reduced sulfur from bacterially or inorganically reduced sulphate, or from an isotopically light reduced S-source. The δ34SH2S values calculated from the barite-H2S and galena-H2S fractionation factors, in the same samples, indicate a temperature of between 200 and 300 °C. Relatively lower δ34S values of barites than dissolved sulphate in modern oceans or Eocene sea waters have been evaluated as the ore forming hydrothermal fluids were derived from interacting throughout the magmatic host-rocks.
The presented investigations aimed at development of inexpensive method for synthesized materials suitable for utilization of solar energy. This important issue was addressed by focusing, mainly, on ...electronic local structure studies with supporting x-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis of colloidal galena nano-particles (NPs) and quantum dots (QDs) synthesized using wet chemistry under microwave irradiation. Performed x-ray absorption near edge structure (XANES) analysis revealed an evidence of quantum confinement for the sample with QDs, where the bottom of the conduction band was shifted to higher energy. The QDs were found to be passivated with oxides at the surface. Existence of sulfate/sulfite and thiosulfate species in pure PbS and QDs, respectively, was identified.
Batch flotation tests of a lead–zinc sulphide composite ore from the Rosh Pinah Mine have been carried out at pH 8.5 in the presence of copper cyanide complexes. These copper cyanide complexes are ...often found in the recycled water that is used in the milling and the lead flotation circuits. Flotation results have shown that cuprous cyanide complexes can activate sphalerite. In addition, the activation and subsequent flotation of sphalerite was greater when the composite was dry milled as compared to wet milling. Surface analysis of copper(I)-activated sphalerite samples was studied by X-ray photoelectron spectroscopy (XPS). XPS results showed the presence of copper species on the surface of sphalerite after activation with cuprous cyanide complexes. The copper species could be removed from the surface of sphalerite after treatment with sodium cyanide. This explains, amongst others reasons, the high cyanide requirement at Rosh Pinah Mine for the efficient depression of sphalerite in the lead flotation circuit.
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