Search

Since the order–disorder phase transition easily occurs during the growth of optoelectronic II–IV–V2 ternary compounds, cation–cation antisites were always considered as the major point defects, while anion-related defects did not attract sufficient attention. In this paper, based on first-principles simulations, the anion–cation antisites are revealed to be comparable to or even dominate over the cation–cation antisites in II–IV–V2 phosphides and arsenides. These antisite defects are predicted to have significant impacts on the optoelectronic properties because they can either act as nonradiative recombination centers or enhance the p-type carrier concentration. Furthermore, based on the calculated defect properties and band alignments, we propose that the alloy ZnGe(P,As)2 can be an efficient p-type solar cell absorber. Its maximal open circuit voltage is effectively enlarged by the low valence band edge; meanwhile, the dominating anion–cation antisites are electrically benign. These results highlight the necessity of considering the anion–cation antisites in the defect engineering of II–IV–V2 phosphides and arsenides. [ABSTRACT FROM AUTHOR]

The research of this paper was carried out on the low-temperature (100 ± 2 °C) pressure (0.2–0.8 MPa) leaching of pyrite, chalcopyrite and their mixture. According to experiments on chalcopyrite dissolution, increasing the oxygen pressure from 0.2 up to 0.8 MPa had a slight effect on chalcopyrite dissolution. Oxygen pressure and initial sulfuric acid concentration in the range of 10–50 g/L had the greatest positive effect on the pyrite oxidation. The SEM and EDX mappings indicate the chalcopyrite and pyrite surfaces to be passivated by elemental sulfur. The oxidation degree of pyrite in its mixture with chalcopyrite increased significantly from 54.5 up to 80.3% in 0–240 min. The reaction time is relative to the dissolution of the individual mineral, while the dissolution of chalcopyrite remained virtually unchanged. The addition of Cu (II) and Fe (III) ions does not influence pyrite dissolution when chalcopyrite is added in a leaching process, which can be explained by the formation of an electrochemical link between the minerals. The positive effect of chalcopyrite addition is associated with a decreased formation of elemental sulfur on the surface of pyrite. The described method can be used for the hydrometallurgical processing of copper raw materials with increased pyrite content, as well as for the pretreatment of copper concentrates with gold-rich pyrite concentrates to increase the recovery of gold and silver. [ABSTRACT FROM AUTHOR]

Experimental investigation of the fractionation behavior of Cu isotopes during the replacement of pyrite by Cu-bearing sulfides (chalcopyrite, bornite, and chalcocite) was conducted under hydrothermal conditions. At the initial stages of the replacement reaction, small mounds of product formed on the pyrite surface; these mounds then grew and coalesced, progressively covering the pyrite grains as the reaction proceeded. Chalcopyrite, bornite, and chalcocite formed sequential monomineralic zones from the pyrite reaction front towards the solution. During the early stage of the reaction, Cu isotope fractionation between the solids and the aqueous solution (Δ65Cu solid-aqueous , Δ65Cu solid-aqueous = δ65Cu solid – δ65Cu aqueous) was approximately –0.6 ‰, similar to the calculated equilibrium Cu isotope fractionation factors between Cu-bearing sulfides (chalcopyrite, bornite, and chalcocite) and CuCl 2 –. However, the Δ65Cu solid-aqueous moved progressively further from equilibrium with prolonged reaction time, with fractionation factors ranging from approximately –0.6 ‰ to –1.2 ‰. We found that significant fractionation of Cu isotopes between the solid products and aqueous solution was mainly controlled by the amount of chalcopyrite that formed in the product layers. We interpret that the Δ65Cu solid-aqueous was controlled by the diffusion of aqueous Cu(I) species among the product layers and the changes in Cu redox state during the precipitation of chalcopyrite. These results imply that the δ65Cu values measured in sulfides from low-temperature hydrothermal deposits may be controlled by the local chemistry of the fluids in product layers that precipitate sulfides. This study highlights the importance of local fluid characteristics, such as redox conditions, metal speciation, and diffusion, in controlling isotope fractionation pathways during non-equilibrium mineral replacement. [ABSTRACT FROM AUTHOR]

The chalcopyrite deposit in Malanjkhand, India, is the largest copper ore producer in the country. However, its flotation performance has room for improvement. This study used standard flotation experiments using a mechanical flotation cell using a conventional collecting reagent and a collector blend consisting of xanthate and ester. A three-factor, three-level Box-Behnken design was used to statistically evaluate the experimental design. The obtained data were analyzed using an ANOVA, cubic plots, and response surface methods. The goal was to evaluate the effects and interactions of three key process parameters in chalcopyrite flotation: the dosages of sodium silicate (depressant), sodium isopropyl xanthate (collector), and acetoacetic acid n-Octyl ester (co-collector/modifier). The results implied that introducing acetoacetic acid n-Octyl ester along with minor tweaks in the dosages of sodium isopropyl xanthate helped increase copper grades by at least 15%, with good recovery percentiles. Among the three parameters tested, the copper's grade and recovery were considerably positively influenced by the AoE dosage in the collector blend. Employing 0.006 kg/t sodium silicate and 0.0065 kg/t sodium isopropyl xanthate with 0.005 kg/t of acetoacetic acid n-Octyl ester, an optimum copper recovery of 88.87% could be achieved. However, with a sodium silicate dosage of 0.0048 kg/t, a SIPX dosage of 0.008 kg/t, and an AoE dosage of 0.005 kg/t, optimized copper grade (1.55%) could be achieved, which is a 78.1% increase from the feed sample grade. To validate the expected results, verification experiments were carried out, and the experimental findings were found to be on at par with the statistical model predictions. Furthermore, the calculated SPI value of 0.0000147cap Kg−1 for a global index per resident lies between 0 and 1. [ABSTRACT FROM AUTHOR]

Tetrahedrite-(Cd), Cu10Cd2Sb4S13, is a member of the tetrahedrite series of the tetrahedrite group with a predominance of Cd at the C position typically occupied by divalent metals. Cadmium end-members from the tetrahedrite group are rare: they have been described in 15 deposits and ore occurrences. This work reports on a new discovery site of Ag-bearing tetrahedrite-(Cd) at the Kon-Dara mineral deposit (Southwestern Pamirs, Tajikistan) and summarizes the known data on rare Cd-bearing fahlores with a Cd content from 1 to 12.31 wt %. Ag-bearing tetrahedrite-(Cd) at the Kon-Dara deposit occurs as xenomorphic segregations 10–35 μm in size in association with tetrahedrite-(Fe), tetrahedrite-(Zn), galena, polybasite, and chalcopyrite, calculated which replace bournonite. According to the EPMA data, its composition averaged over seven analyses (in wt %) is as follow: Ag 16.17, Cu 25.19, Cd 10.09, Fe 0.38, Zn 0.09, Pb 0.13, Sb 25.55, As 0.18, and S 22.34. The empirical formula calculated based on 29 atoms per unit is (Cu7.40Ag2.80)Σ10.20(Cd1.68Fe0.13Zn0.03Pb0.01)Σ1.84(Sb3.92As0.04)Σ3.96S13.00. The composition of the tetrahedrite-(Cd) from Kon-Dara is similar to those from the Tyndrum Pb–Zn mineralization in Scotland, the Clara baryte–fluorite–(Ag,Cu) mine in Germany, and the Xitieshan Pb–Zn deposit in China. The formation temperature of Ag-bearing tetrahedrite-(Cd) at the Kon-Dara deposit is estimated to have been at about (170–140) ± 20°C. [ABSTRACT FROM AUTHOR]

Chalcopyrite selenide single crystals and epitaxial layers (CuIn1−xGaxSe2, x = 0.00, 0.08, 0.19, 1.00) were characterized by temperature‐dependent photoreflectance (PR), photoluminescence (PL), photoluminescence–excitation (PLE), and variable excitation‐energy photoluminescence (VEPL) spectroscopy. The transition energies Ea, Eb, and Ec of both CuInSe2 (CIS) and CuGaSe2 (CGS) layers sensed by PR were higher than the energies of single crystals. CuInSe2 and CuGaSe2 grown on GaAs(001) underlie compressive and tensile stresses, respectively, which lead to band‐gap broadening in CIS and band‐gap narrowing in CGS. The increase of the Ea, Eb, Ec energies of tensely stressed CuGaSe2 layers to energies higher than those of the bulk originates from the stress dependence of the non‐cubic crystal field. Band‐gap scanning of the CuGaSe2 layer with continuous‐wave Ti:sapphire‐laser confirmed the absence of correlation between band‐gap readjustment and intrinsic defects. The energy of the band‐edge exciton EFE, in the PL‐spectra, was lower than the Ea transition energy, in the PR‐spectra, which is assigned to partial quenching of ΔCF with the increase of external tensile stress by gallium‐segregation at the chalcopyrite/GaAs‐interface. The stress dependence of ΔCF is negligible in CuInSe2 and linear, with a rate of 9 meV/100 MPa, in CuGaSe2. It is revealed that the energy band‐gap of photovoltaic chalcopyrite absorbers can be tuned by simultaneous built‐in and external lattice‐tuning. [ABSTRACT FROM AUTHOR]

Aluminum recycling is an important step to achieve high value-added utilization of fly ash to improve the leaching efficiency of Al. In this paper, Na2CO3 was used as the flux and HCl as the leaching solution to extract Al from CFA by using the roasting activation-acid leaching process to investigate the influencing factors of the leaching rate of Al to analyze the mineral composition of the roasting products explore the activation process of CFA roasting. The experimental results showed that compared with NaF, CaO, and NaOH, the highest Al leaching rate was achieved when Na2CO3 was used as a flux, at which time the leaching rate could reach up to 81.62%, and it was about 63% higher than that of extracting Al from the fly ash using direct roasting-acid leaching method. When the roasting time is 90 min, the roasting temperature is 850°C, the CFA/Na2CO3 is 1.5, the hydrochloric acid concentration is 4 mol/L, the acid leaching temperature is 90°C, the S/L is 1:4, and the maximum leaching rate of Al is 81.62%. According to the thermodynamic theory, Na2CO3 and mullite gradually reacted with each other above 800 K to form chalcopyrite, and Na2CO3 reacted with mullite and quartz in CFA to form chalcopyrite more easily. According to the reaction kinetic model, the acid leaching process of CFA is mainly controlled by diffusion, and a semi-empirical equation is proposed to describe the whole leaching process. [ABSTRACT FROM AUTHOR]

Chalcopyrite, the world's primary copper ore mineral, is abundant in Latin America. Copper extraction offers significant economic and social benefits due to its strategic importance across various industries. However, the hydrometallurgical route, considered more environmentally friendly for processing low‐grade chalcopyrite ores, remains challenging, as does its concentration by froth flotation. This limited understanding stems from the poorly understood structure and reactivity of chalcopyrite surfaces. This study reviews recent contributions using density functional theory (DFT) calculations with periodic boundary conditions and slab models to elucidate chalcopyrite surface properties. Our analysis reveals that reconstructed surfaces preferentially expose S atoms at the topmost layer. Furthermore, some studies report the formation of disulfide groups (S22−) on pristine sulfur‐terminated surfaces, accompanied by the reduction of Fe3+ to Fe2+, likely due to surface oxidation. Additionally, Fe sites are consistently identified as favourable adsorption locations for both oxygen (O2) and water (H2O) molecules. Finally, the potential of computer modelling for investigating collector–chalcopyrite surface interactions in the context of selective froth flotation is discussed, highlighting the need for further research in this area. [ABSTRACT FROM AUTHOR]

Chalcopyrite has been extensively utilized for tracing geological processes through its Cu, Fe and S isotopic compositions. However, the matrix-matched reference materials for micro-analysis are lacking. This study focused on assessing the feasibility of a natural chalcopyrite specimen (IGGCcp-1) as a matrix-matched reference material for in situ micro-analysis of Cu, Fe, and S isotopes. Electron probe microanalysis validated the uniform distribution of major elements within chalcopyrite grains, with no evidence of growth zoning. Random spot isotopic measurements using LA-MC-ICP-MS demonstrated remarkable consistency in δ65Cu, δ56Fe and δ34S. These results indicated that the IGGCcp-1 specimen exhibited its suitability as a reference material. Using SN-MC-ICP-MS technique, the δ65Cu value was accurately determined to be 0.43 ± 0.05‰ (2S, N = 30). Furthermore, the δ56FeIRMM-014 and δ57FeIRMM-014 values were recorded as -0.24 ± 0.04‰ (2S, N = 18) and -0.36 ± 0.09‰ (2S, N = 18), respectively. Additionally, the δ34SVCDT measurement, performed with EA-IRMS, yielded a value of -0.28 ± 0.60‰ (2S, N = 10). These precisely measured isotope ratios established the recommended reference values for the IGGCcp-1 sample in future applications of Cu, Fe, and S isotope micro-analysis. [ABSTRACT FROM AUTHOR]

A simple, rapid, economical, and non-enzymatic electrochemical sensor for sensitive determination of hydrogen peroxide (H2O2) was developed based on a physical combination of carbon black (CB) and pure chalcopyrite modified glassy carbon electrode (GCE). Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) were used to evaluated the morphology of the modified electrode. The proposed sensor (CuFeS2-CB/GCE) was investigated electrochemically using cyclic voltammetry (CV), amperometric methods (AP), and electrochemical impedance spectroscopy (EIS). The CuFeS2-CB/GCE sensor exhibited excellent stability and sensitivity with a linear concentration range from 2.5 to 60 mM (R2 = 0.9903) using CV and 0.1 to 100 mM (R2 = 0.9999) using AP. The corresponding limits of detection (LOD) are 1.0 mM and 0.04 mM (S/N = 3) for CV and AP, respectively. Both linear range and sensitivity of the prepared sensor were enhanced through the combination of chalcopyrite and CB. The practicality of the proposed sensor was further tested by measuring H2O2 in real samples. Additionally, the prepared sensor showed good selectivity to H2O2, resisting interference from other potential interferent compounds (e.g., glucose, fructose, urea, catechol, and common metal ions), and the sensor possesses acceptable long-term stability. [ABSTRACT FROM AUTHOR]

This is an article in the field of mineral processing engineering. For the flotation of sulfide ores whose gangue mineral is serpentine, serpentine can deteriorate the flotation of sulfide ores due to its easy mudification. To solve this problem, 2-hydroxyphosphonoacetic acid (HPAA) was used for the first time in this paper to eliminate the negative effect of serpentine on chalcopyrite flotation. In this article, the effect of HPAA on chalcopyrite/serpentine flotation system and the mechanism of action were investigated by microflotation test, turbidity test, zeta potential test, adsorption amount test and XPS test. The tests showed that serpentine is positively charged and chalcopyrite is negatively charged. Due to the electrostatic attraction, serpentine slime will adsorb on the surface of chalcopyrite, thus inhibiting the flotation of chalcopyrite. After adding HPAA, the flotation recovery of chalcopyrite was increased from 47.85% to 92.44%. The mechanism was that HPAA chemisorbed with Mg2+ of serpentine, which significantly reduced the surface potential of serpentine and caused repulsive effect on mineral particles, thus recovering the floatability of chalcopyrite.

In seawater flotation, some chemical properties of seawater affect the flotation separation of chalcopyrite and sphalerite. Using seawater instead of fresh water to separate copper – zinc can save fresh water resources and reduce lime consumption, which has broad prospects in terms of economic and environmental protection. In this paper, the flotation separation behavior of chalcopyrite and sphalerite in seawater was tested and the mechanism was analyzed. As a contrast, the copper grade of concentrate in seawater flotation declined from 23.7% to 22.6%. Meanwhile, the recovery of chalcopyrite declined from 66.2% to 42.8% and the SI value declined from 2.210 to 1.599. With the addition of sodium hexametaphosphate, sodium silicate and EDTA, the SI value increased from 1.599 to 2.176, 2.238 and 2.096, respectively. Nevertheless, when EDTA was excessive, the SI value was only 1.998. This indicated that excessive EDTA is unfavorable to flotation separation of chalcopyrite from sphalerite. Wettability analysis, zeta potential analysis, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, density functional theory calculation and E-DLVO calculation verified the flotation separation behavior and revealed the mechanism. [ABSTRACT FROM AUTHOR]

A novel small molecule depressant (M-DEP) was used to separate chalcopyrite and molybdenite via flotation. The results showed that M-DEP had an excellent selective depression on molybdenite, while had little effect on the flotation of chalcopyrite. The adsorption capacity of M-DEP on the surface of molybdenite was greater than that on chalcopyrite surface. The adsorption of M-DEP reduced the floatability of molybdenite and had less effect on the floatability of chalcopyrite, which was due to its different adsorption modes on the surface of the two minerals. Furthermore, the interaction between chalcopyrite and M-DEP was mainly chemical interaction, and almost all of the adsorbed M-DEP molecules were removed and replaced by sodium butyl xanthate (SBX). By contrast, hydrophobic interaction was the main way in which M-DEP was adsorbed on the molybdenite surface with little chemical interaction, which was less interfered by SBX addition. Therefore, M-DEP had a super selective depression on molybdenite. The study provided a novel depressant and approach for the deep separation of chalcopyrite and molybdenite via flotation.

Although the flotation separation of sulfides and their electrochemical interactions have been examined in some investigations, study the direct relationship between the flotation kinetics of sulfides and their galvanic interactions during the process yet has not been addressed. To fill this gap, an extensive study was conducted to explore the effect of galvanic interactions for chalcopyrite and pyrite on their flotation kinetics when they are wetting ground by three different grinding media types (steel, chromium, and ceramic). Assessment of the flotation test results indicated that there was no galvanic interaction between the ceramic grinding balls and chalcopyrite. The galvanic interactions were mostly related to the grinding of chalcopyrite by steel balls. EDTA analysis showed that by increasing the amount of iron oxy/hydroxy and their precipitations on the surface of chalcopyrite, the recovery of chalcopyrite was decreased. Furthermore, increasing the pyrite content in the flotation of chalcopyrite increased the flotation rate constant and then decreased it. Flotation tests demonstrated that grinding chalcopyrite by ceramic media type, which has lower electrochemical activity in comparison with the other considered media, can be resulted in a higher flotation rate constant and ultimate recovery. Grinding the mixture of chalcopyrite and pyrite by steel or chromium media can show almost the same effect on the flotation rate constant and ultimate recovery. In general, the experimental results showed that by increasing the galvanic interaction, the flotation recovery and flotation kinetics were decreased.

Chalcopyrite and galena are primary raw materials for producing Cu and Pb metals, respectively. Flotation is still the main method to recover these two minerals. So far, lots of work has been done to recover them from low-grade refractory ores, whereas the efficient separation of these two minerals remains a major challenge. In this review, the crystal, surface, floatability and needed reagents were discussed. Firstly, the crystalline structures were introduced, including physical and chemical properties, and followed by surface properties from a density functional theory simulation perspective. As reviewed, the surface properties were closely related to their floatability, such as the degree of surface oxidization, particle size, galvanic interactions, metal ions, and so on. Moreover, the floatability of minerals could be influenced by flotation reagents, and therefore a range of new collectors and depressants were described. The review aimed to provide a deep understanding on the factors affecting Cu/Pb flotation separation as well as to develop new depressants helping to guide the flotation separation of Cu/Pb/Zn polymetallic sulfide ores for researchers. [ABSTRACT FROM AUTHOR]

Daqingshanite in the Kamthai REE deposit (India) occurs as two paragenetic types: primary granular coarse grained crystals coexisting with primary carbocernaite, baryte and bastnäsite; and as aligned micro-ovoid globules within clasts of Sr-bearing calcite. Carbocernaite forming trellis-type lamellae in some of these calcite clasts do not represent exsolution and are considered as replacement textures as they formed subsequent to daqingshanite. The origins of the textural relations of the microglobules of daqingshanite to their host Sr-calcite cannot be unambiguously determined, although an exsolution origin is not considered feasible. The textures are similar to those of 'chalcopyrite disease' and as such could be interpreted as replacement features formed in a low temperature carbothermal environment which should facilitate replacement. Given that daqingshanite is an early crystallising phase it is also possible that cotectic crystallisation with Sr-calcite occurred, followed by subsolidus re-equilibration with recrystallisation along specific crystallographic planes in the calcite. The Kamthai REE deposit is best described as a low temperature carbothermalite microbreccia consisting of a wide variety of clasts resulting from the autobrecciation of rocks formed during, and after, the magmatic to carbothermal transition of an undetermined parental calcite carbonatite-forming magma. Many clasts have been replaced by late stage La-enriched carbothermal fluids mixed with exogenous water during the final low-temperature stage of evolution of the deposit. [ABSTRACT FROM AUTHOR]

The concentrate grade in chalcopyrite flotation is often compromised by the associated inherently floatable gangue such as graphite. In this study, eco-friendly xanthan gum (XG) was introduced as a graphite depressant in the flotation of chalcopyrite. Single minerals flotation showed that XG strongly reduced the floatability of graphite at pH 7.5 with no significant effect on the flotation of chalcopyrite. Mixed minerals flotation showed that the addition of 20 mg/L XG increased copper grade and selectivity index by 16.83% and 14.23, respectively. This selective depressing behavior of XG was due to the strong affinity between XG and graphite as well as the weak interaction between XG and chalcopyrite, as suggested by electrokinetic and adsorption measurements. FTIR and XPS analyses indicated that the adsorption of XG on the graphite surface could be governed by physical adsorption mechanisms. Furthermore, since the contribution of hydrogen bonding interaction was insignificant, hydrophobic interaction was considered as the dominant driving force in the adsorption process. This investigation demonstrates the promising potential of XG for graphite depression and may contribute to the greening of chalcopyrite flotation process. [ABSTRACT FROM AUTHOR]

Chalcopyrite ores are processed mostly by pyrometallurgical techniques due to the refractory nature of the mineral to the current hydrometallurgical techniques. In order to overcome such refractoriness, pretreatment steps such as sulfurization may be applied to produce different copper phases and therefore improve the metal dissolution in the leaching step. The current study investigated the reaction products of the reaction between chalcopyrite and elemental sulfur at different chalcopyrite/sulfur ratios (1/1 and 1/2), reaction time (60 min and 90 min), and temperature (350ºC, 400°C and 450ºC). The sulfurization experiments revealed that covellite, nukundamite, bornite, and pyrite-like compounds were produced according to the experimental conditions applied. Then, the sulfurization products were submitted to chemical leaching tests at temperatures ranging from 32ºC to 70ºC, whereas bioleaching tests were also carried out with Acidithiobacillus ferrooxidans, at 32ºC. In the chemical leaching experiments at 70ºC, only 14% copper was recovered from the original chalcopyrite sample while the maximum copper extraction was 78% from bornite produced at 450ºC (90 min and mass ratio of chalcopyrite/sulfur of 1/2). On the other hand, copper extraction achieved 96% from the same sulfurization product containing synthetic bornite within 20 days of bioleaching. Bioleaching of the original chalcopyrite sample implied in a copper recovery of only 25% in the same period. Summarizing, the current work showed that chalcopyrite sulfurization at 450ºC was able to transform chalcopyrite into a bornite-like phase, which was chemically leached and bioleached by At. ferrooxidans. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cathodoluminescence and electron backscatter diffraction have been applied to exactly the same grain boundaries (GBs) in a Cu(In,Ga)S2 solar absorber in order to investigate the influence of microstructure on the radiative recombination behaviour at the GBs. Two different types of GB with different microstructure were analysed in detail: random high angle grain boundaries (RHAGBs) and Σ3 GBs. We found that the radiative recombination at all RHAGBs was inhibited to some extent, whereas at Σ3 GBs three different observations were made: unchanged, hindered, or promoted radiative recombination. These distinct behaviours may be linked to atomic-scale grain boundary structural differences. The majority of GBs also exhibited a small spectral shift of about ±10 meV relative to the local grain interior (GI) and a few of them showed spectral shifts of up to ±40 meV. Red and blue shifts were observed with roughly equal frequency. [ABSTRACT FROM AUTHOR]

The challenges that the mining industry has to face in order to achieve tailings disposal in accordance with the principles of a closed-loop economy include improving rather limited knowledge about mineralogy, impurity concentrations and tailings volume in tailings dumps. It is also necessary to develop technologies to make the process economically feasible. In order to improve the performance of the grinding operation and have a significant impact on the enrichment of valuable components, the effects of ultrathin grinding on the degree of disclosure of copper minerals of dump tailings were studied. Based on optical and mineralogical studies, it was found that the completely uncovered chalcopyrite grains make up no more than 35% of the total number of grains, their size is mainly (by 60% relative) within the class of 10-45 microns. Analysis of the sieve characteristics of the tailings after ultrathin grinding shows that the highest concentration of copper falls on the thinnest class -0.006+0 mm, that indicates a high disclosure of copper minerals due to ultrathin grinding. Flotation tests to determine the effect of the degree of ultrathin grinding showed that with an increase in the fineness of grinding in the size class - 0.045 + 0 mm to 86%, the extraction of copper increases from 66.49 to 73.52%; gold 71.07 to 77.78%; silver 70.29 to 76.71%. [ABSTRACT FROM AUTHOR]

The effect of organic depressant DP115 (modified polyacrylamide) on the flotation of chalcopyrite and sphalerite was investigated using micro-flotation tests, and different added orders of DP115 and Z-200 were also studied. When DP115 is added first, its depression effect on sphalerite is considerable, but on chalcopyrite is weak; but when Z-200 is added first, DP115 has little depression effect on chalcopyrite flotation, whereas still strongly depresses sphalerite. The results of flotation tests on artificially mixed sample of minerals showed that for chalcopyrite-sphalerite (1:1) artificially mixed sample using Z-200 and DP115 as collector and regulator respectively, under the same flotation conditions, the selective separation index was 10.09 higher when the DP115 was added after Z-200, compared with that when the DP115 was added before Z-200. The results of the flotation separation of artificially mixed samples were in good agreement with those of single mineral flotation test, which verified the results of flotation separation of single minerals. The interaction between DP115 and Z-200 on the sulfide surface was studied by adsorption measurement. It is indicated that the Z-200 strongly absorbs on the chalcopyrite surface, and DP115 has little impact on the adsorption of Z-200 on the chalcopyrite surface, while the adsorption of Z-200 on the sphalerite surface is weak, and the competitive adsorption between DP115 and Z-200 adsorbed on the surface of sphalerite results in the desorption of Z-200 on the sphalerite surface. Time of flight secondary ion mass spectrometry (ToF-SIMS) analysis suggests that as compared to the addition first of DP115, less DP115 and more Z-200 are adsorbed on the chalcopyrite surface, while more DP115 and less Z-200 are adsorbed on the sphalerite surface, when Z-200 is added first, and so as to be more useful to realize the flotation separation of Cu-Zn. [ABSTRACT FROM AUTHOR]

In the course of this investigation, we performed ab initio calculations. The investigation systematically explored the physical features of chalcopyrite-phase BeXAs2 (X=Sn and Ge). Total energy calculations incorporated the Wu-Cohen generalized gradient approximation (WC-GGA) [1] to consider the exchange-correlation potential. The analysis of band structures employed the modified Becke Johnson (mBJ) [2] potential approximation, renowned for its effectiveness in addressing concerns related to band gaps. The optical properties of these materials were further elucidated through the determination of the dielectric function and absorption coefficient. The analysis of electronic and optical characteristics underscores the potential applications of BeXAs2 compounds in photonics, optoelectronics, and photovoltaics. Notably, the results exhibit strong agreement with both prior theoretical investigations and experimental data. [ABSTRACT FROM AUTHOR]

Low-temperature bioleaching is relevant to the recovery of metals in alpine mines, but its development has been constrained by low bioleaching rates at high pulp concentrations. To this end, the bioleaching effect of the microbial community after the domestication of pulp concentration at 6 °C was studied. Domestication improved the bioleaching rate of copper. Environmental scanning electron microscopy (ESEM), X-ray diffraction (XRD), and electrochemical measurements revealed that the domestication process aggravated the corrosion of the chalcopyrite surface by accelerating its dissolution reaction. High-throughput sequencing technology indicated that Acidithiobacillus spp., Leptospirillum spp., and Acidiphilium spp. were the major lineages of the domesticated microbial community. The analysis of the microbial community revealed that domestication changed the microbial structure, enhancing the adaptability of the microbial community to pulp concentrations and acidic conditions. This study uncovered the mechanism by which domestication enhanced the bioleaching efficiency of the microbial community at low temperatures. [ABSTRACT FROM AUTHOR]

AgGaTe2 is an attractive material for the light‐absorbing layer in solar cells and has been deposited by close‐spaced sublimation using Ga2Te3 powder source. However, the samples exhibit an excess of Te, as well as undesired Mo–Te compounds, when AgGaTe2 is deposited on Mo/glass substrates. Therefore, the AgGaTe2 light‐absorbing layer is deposited using an Ag2Te and GaTe mixed powder source and examined herein. By replacing the Ga2Te3 source with GaTe, the Te content confirmed by the X‐ray fluorescent has significantly decreased. Cross‐sectional transmission electron microscopy observation indicates that the formation of Mo–Te compounds is suppressed. This is because Ga2Te3 produces additional Te gas in the initial decomposition reaction during deposition, and GaTe does not. In addition, the J–V curves show an improved conversion efficiency for solar cells fabricated using GaTe. [ABSTRACT FROM AUTHOR]

Copper leaching presents an environmentally friendly alternative to traditional sulfide ore processing methods. This study investigates an efficient leaching process for copper concentrate, utilizing a solution of sulfuric acid (H2SO4) and potassium iodide (KI) in a chloride medium (NaCl), enhanced by hydrogen peroxide (H2O2) at room temperature. A significant aspect of this research was optimizing the KI concentration to minimize iodide sublimation into iodine gas (I2). Through the experimental design, the optimal dosages of reagents were determined, leading to maximized copper extraction of approximately 27% in 45 min of testing at room temperature. The results showed that it is possible to obtain a suitable pregnant leach solution (PLS) (i.e., in the range of 3 to 8 g/L of Cu) for treatment in available copper solvent extraction (SX) plants with a cost of less than 4.5 USD/t Cu, according to the economic analysis carried out. The results of this study determine the most effective operational conditions for leaching and ensure a suitable PLS for SX plants in a cost-effective and environmentally friendly manner. This approach could significantly contribute to more sustainable practices in the mining and processing of copper ores. [ABSTRACT FROM AUTHOR]

Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

\nKEY FINDINGSThe demand for copper drives hydrometallurgical innovation amidst high-grade resource depletion. Compared to pyrometallurgy, biohydrometallurgy presents eco-friendly, cost-effective solutions for ore processing. Semiconductor minerals, notably chalcopyrite, which corresponds to the largest source of copper in the earth’s crust, play a critical role. However, chalcopyrite electrochemical behavior in bioleaching remains underexplored. Therefore, this review emphasizes the exploration of irradiation’s influence on biohydrometallurgy, particularly through the utilization of photoreactions or mineral photo corrosion. The focus is on examining the semiconductor properties of chalcopyrite to incorporate it into biohydrometallurgical frameworks and to develop models elucidating the impact of light on the bioleaching of chalcopyrite.Chalcopyrite leaching is governed by semiconductive properties rather than passive layer formation.The transport of charge carriers across the space charge region may be the rate-limiting step in hydrometallurgical processes.High solution potentials lead to charge carrier depletion and reduced reaction kinetics in the dark.Electron injection into Fe3d S3p antibonding orbitals at low solution potentials increases charge carrier concentration, enhancing reduction and intermediate formation.Light irradiation boosts reaction rates by exciting electrons, facilitating their capture by Fe3+ ions, aiding bioleaching, and injecting electrons into the photo-generated holes.Chalcopyrite leaching is governed by semiconductive properties rather than passive layer formation.The transport of charge carriers across the space charge region may be the rate-limiting step in hydrometallurgical processes.High solution potentials lead to charge carrier depletion and reduced reaction kinetics in the dark.Electron injection into Fe3d S3p antibonding orbitals at low solution potentials increases charge carrier concentration, enhancing reduction and intermediate formation.Light irradiation boosts reaction rates by exciting electrons, facilitating their capture by Fe3+ ions, aiding bioleaching, and injecting electrons into the photo-generated holes.Suggestions for future research in the area of biohydrometallurgy: Investigate conditions favoring the accumulation of majority charge carriers on the chalcopyrite surface.Explore light irradiation with sufficient energy to excite electrons from the valence band to the empty orbitals between the valence and conduction bands and the conduction band itself, using different wavelengths.Study the combined effects of light and iron-oxidizing microorganisms on chalcopyrite bioleaching.Therefore, understanding and applying the semiconductor nature of chalcopyrite is crucial for improving hydrometallurgical processes and enhancing copper recovery efficiency through photo-biohydrometallurgy.Investigate conditions favoring the accumulation of majority charge carriers on the chalcopyrite surface.Explore light irradiation with sufficient energy to excite electrons from the valence band to the empty orbitals between the valence and conduction bands and the conduction band itself, using different wavelengths.Study the combined effects of light and iron-oxidizing microorganisms on chalcopyrite bioleaching.Therefore, understanding and applying the semiconductor nature of chalcopyrite is crucial for improving hydrometallurgical processes and enhancing copper recovery efficiency through photo-biohydrometallurgy. [ABSTRACT FROM AUTHOR]

Aluminum‐based chalcopyrite materials have attracted attention because of the wide controllability range of their material properties and potential for use in energy‐conversion devices. Herein, CuAlSe2‐based thin‐film growth and solar cell device properties are discussed. Ternary CuAlSe2 thin films are relatively unstable and decompose weeks after film growth, even when preserved in a dry box. However, alloying with elemental In led to significant improvements in stability. Cu(In,Al)Se2 (CIAS) solar cells yield better photovoltaic performance than CuInSe2 cells, although the effective range of Al concentration that can improve device performance is narrower than that of elemental Ga in Cu(In,Ga)Se2 (CIGS). A decrease in the alkali metal concentration in CIAS films with increasing Al concentration is observed, indicating that the formation energy of alkali‐metal substitutional defects on the Cu site is high, and/or Al‐related complex defects formed are kinetically stable and difficult to replace with alkali metals once they form. Although the direct observation of alkali metals in the bulk (grain interior) of chalcopyrite CuInSe2 and CIGS films has been difficult to date, this result can serve as indirect evidence of the presence of alkali metals in the bulk of CuInSe2 films. [ABSTRACT FROM AUTHOR]

High‐efficiency Cu(In,Ga)Se2 solar cells rely on Ga grading to mitigate back surface recombination. However, the inhomogeneous absorber has drawbacks, including increased non‐radiative loss and inadequate absorption. Therefore, literatures demand a paradigm shift of using a hole‐transport layer to passivate the back surface. Herein, a functional hole‐transport layer is demonstrated as an alternative to Ga grading. The novel hole‐transport layer is prepared as a double‐layer: co‐evaporated CuGaSe2 covered by solution combustion synthesis prepared In2O3. As demonstrated by micrographs, elemental mapping, and photoluminescence spectroscopy, the oxide layer improves thermal stability and prevents Ga diffusion. However, during the absorber deposition, a complete ion exchange of In and Ga converts CuGaSe2/In2O3 into CuInSe2/GaOx. Incorporating this hole‐transport layer in co‐evaporated nongraded CuInSe2 solar cells leads to significantly increased minority carrier lifetime from 5 to 113 ns, yielding an 80 meV improvement in quasi‐Fermi‐level splitting. The devices exhibit improved open‐circuit voltage, as well as a promising fill factor of over 71%, indicating good hole‐transport properties. In these results, the passivation effect and good hole‐transport properties of the hole‐transport layer are experimentally demonstrated. Thus, high‐efficiency solar cells can be achieved by using a functional hole‐transport layer without relying on Ga grading. [ABSTRACT FROM AUTHOR]

The demand for non-ferrous copper metals has increased dramatically with the development of the global economy; accordingly, some refractory copper sulfide ores with low grade and their associated minerals are beginning to be utilized, making the flotation separation of copper concentrates exceptionally difficult, especially the separation of chalcopyrite and pyrite. In this paper, S-allyl-O, O′-dibutyl phosphorodithioate (ADTP) was synthesized by a one-pot method and used as a chalcopyrite collector in the flotation separation of chalcopyrite and pyrite. Flotation experiments results have shown that ADTP exhibits better selectivity and greater collecting power for chalcopyrite under neutral or weak base conditions. The 95% recovery of chalcopyrite can be achieved at pH 8.0 and 8.0 mg/L ADTP. From the analysis results of the contact angle, the SEM-EDS spectrogram, and elemental mapping, it was found that ADTP adsorbed uniformly on a chalcopyrite surface and made a significant contribution to the hydrophobicity of the surface. Confirmed by FTIR and XPS analysis, ADTP was able to form P–S–Cu bonds on a chalcopyrite surface, proving that it was adsorbed on the chalcopyrite surface in the form of chemisorption. [ABSTRACT FROM AUTHOR]

In order to substantiate the possibility of obtaining glass–ceramics from glasses based on slags from the joint smelting of silicate nickel and copper pyrite ores, the crystallization ability of model samples (particle size < 0.1 mm) that are close in composition and structure to real prototypes was evaluated. Using the methods of differential scanning calorimetry (5–20 °C·min−1 heating rate) and X-ray powder diffraction, it was established that in an inert atmosphere, crystallization is accompanied by the formation of products, the crystalline part (46.6–71.6 mass%) of which is represented by associations of pyroxenes and anorthite. The primary crystallizing phase is pyroxene. The transition from iron-free to iron-containing sample leads to a change in the composition of pyroxene from enstatite to pigeonite, a shift in the range of formation of these associations from 826–1018 to 728–874 °C, and additional (966–1068 °C) formation of silica. Kinetic analysis (Ozawa–Flynn–Wall and multi-variate nonlinear regression methods) showed consecutive bulk nucleation of pyroxenes and anorthite with the formation of two- and one-dimensional nuclei by a chain mechanism, passing into diffusion-controlled two- and three-dimensional crystal growth. The activation energy of enstatite nucleation (671 kJ·mol−1) is significantly higher than for pigeonite (418 kJ·mol−1), and for crystal growth (444 and 534 kJ·mol−1, respectively), the reverse relationship is noted. Pyroxenes promote the heterogeneous nucleation of anorthite. The activation threshold for the release of the latter in an iron-free sample (220 kJ·mol−1) is three times higher than in an iron-containing one (76 kJ·mol−1). The formation of two- and one-dimensional silica nuclei in the bulk of glass is synchronized with their two-dimensional growth under conditions of diffusion deceleration. The results obtained can be used in the development of technologies for producing glass–ceramics from various types of technogenic and mineral raw materials. [ABSTRACT FROM AUTHOR]

The adsorption of a conductive mineral toward a collector changes its interface electrochemical property, implying the hydrophobization mechanism of froth flotation. Herein, the interface electrical behavior of chalcopyrite was investigated by in situ scanning electrochemical microscopy (SECM). And the results demonstrated that the treatment of N, N-diethyl-S-[2-amino-2-(hydroxyimino) ethyl] dithiocarbamate ester (DEAHEDTC) significantly reduced the tip feedback current i and heterogenous electron transfer rate constant k of chalcopyrite interface, implying the self-assembly of DEAHEDTC on chalcopyrite surface. The adsorption mechanism investigations further revealed that both DEAHEDTC's C(=NOH)-NH2 and N-C(=S) groups combined with the surface Cu atom(s) of chalcopyrite, leaving its hydrophobic groups outward against chalcopyrite. For the hydrophobic groups that are non-conducting, the electrochemical activity of chalcopyrite interface decreased. While the hydrophobization of DEAHEDTC returned a high flotation recovery of chalcopyrite particles. [ABSTRACT FROM AUTHOR]

The oxidative flotation separation of chalcopyrite from pyrite in weak alkaline seawater solution was investigated using potassium ferrate (K2FeO4) as the oxidizing reagent. The optimal K2FeO4 concentration of 0.25 kg/t was found to strongly depress pyrite (from 88.05% to 7.92%) but insignificantly influence chalcopyrite (remaining at around 93%). K2FeO4 oxidized pyrite to form hydrophilic Fe2O3, Fe(OH)3, FeOOH, and Fe2(SO4)3 that covering on pyrite surface to prevent the adsorption of collector sodium butyl xanthate (SBX), thereby depressing pyrite flotation. Although a small amount of hydrophilic species was formed on chalcopyrite surface after the addition of K2FeO4, some hydrophobic substances such as S22-/Sn2-/S0 were also observed, resulting in an unaffected overall floatability. Further, density functional theory (DFT) calculation proved that the activity of Fe on chalcopyrite surface was much lower than that on pyrite. Therefore, this study provides a green way to separate chalcopyrite from pyrite effectively in a low-alkali seawater system, which is of significance to the separation of sulfide minerals in the fresh water-lack areas. [ABSTRACT FROM AUTHOR]

Ag-Pb-Cu mixed concentrate is a product ofcopper and lead floating and contains a silver grade of 4208.0 g/t, along with 3.3% of copper and 43.28% of lead. And 98.80% of silver is deposited in galena. The surface of the concentrate has been heavily contaminated with the flotation reagents, leading to a little difference in the floatability between galena and chalcopyrite. Consequently, separating chalcopyrite from galena is very difficult. In this experimental study, a combined process of removing the flotation reagents by activated carbon and flotating copper by the suppression of lead was adopted to treat the concentrate. By using a high-efficiency galena inhibitor (GYC) and chalcopyrite collector (SAC), an effective recovery of silver, lead and copper from the mixed concentrates was achieved. After the treatment of the mixed concentrate, the silver grade in obtained silver-lead concentrate was 4839.2 g/t with a recovery rate of 97.36% and the grade of lead was 50.05% with a recovery rate is 97.90%. In obtained copper concentrate, the silver grade was 724.6 g/t with a recovery rate of 2.64% and the copper grade was 20.16% with a recovery rate of 91.23%. [ABSTRACT FROM AUTHOR]

Chalcopyrite ore is one of the most abundant and pertinent oxidized copper minerals. In this research, the dissolution kinetics of chalcopyrite in an ammonia solution was examined. During leaching, the influences of leachant concentration, temperature, and particle diameter on the extent of copper ore dissolution were investigated. However, it was affirmed that the dissolution efficiency of chalcopyrite ore increased with decreasing particle fraction and increasing reaction temperature and ammonia concentration. About 68.6% copper ore dissolution was achieved with 2.0 mol/L NH3, 75 ºC reaction temperature, and 45 μm particle diameter within 120 minutes. The dissolution reaction mechanism was found to be described by diffusion-control with a calculated activation energy of 32.26 kJ/mol. In the XRD spectra of the residual product obtained at established conditions, CuFeS2 peaks were absent, indicating the leachability of the sample. Hence, the leach residue could serve as an important by-product for some local industries. [ABSTRACT FROM AUTHOR]

This paper review presents a comparison between conventional leaching and advanced photochemical leaching processes and their potential for use in chalcopyrite leaching. Likewise, it presents an analysis of the differences between the advanced leaching processes, photoleaching and radical-leaching, indicating that the photochemical mechanisms (photooxidation/photoreduction and generation of radical oxygen species (ROS) and radical sulfur species (RSS)) would improve the oxidative dissolution of chalcopyrite, taking advantage of the high oxidizing power of free radicals. Initial experimental results of solar-assisted radical-leaching on chalcopyrite are presented, demonstrating that sulfate radicals (SO4−) allow copper to be leached at a rate 4.7 times higher than in the absence of radicals and sunlight. With these results, a radical-leaching process is presented for the first time, with a perspective toward the future development of a new hydrometallurgical route: solar-assisted radical-leaching. [ABSTRACT FROM AUTHOR]

The effect of adding orders of inorganic regulators such as zinc sulfate, copper sulfate, sodium sulfite and sodium sulfide on the flotation of chalcopyrite, galena, and sphalerite was studied under the Z-200 collector system. The results of microflotation tests showed that compared with adding inorganic regulator before the Z-200, when the inorganic regulator was added after the Z-200, there were differences in the effect on the flotation of the three kinds of sulfide minerals: the depressing effect of zinc sulfate on chalcopyrite, especially galena, was significantly weakened, and the depressing effect of zinc sulfate on sphalerite was weakened at lower dosage, but stronger at higher dosage. Copper sulfate slightly enhanced the depressing effect on chalcopyrite, had a strong activation effect on galena, especially at lower dosage, the activation effect of copper sulfate on sphalerite was significantly enhanced at lower dosage, and was weakened at higher dosage. Sodium sulfite weakened its depressing effect on chalcopyrite, especially galena, and enhanced the depressing effect on sphalerite. Sodium sulfide weakened its depressing effect on chalcopyrite, had a similar activation effect on galena at lower dosage, while its depressing effect was enhanced at higher dosage, and enhanced its depressing effect on sphalerite at low dosage. The research results can provide reference for the selection and the adding sequence of inorganic regulators in the flotation separation of sulfide ores under the Z-200 collector system. [ABSTRACT FROM AUTHOR]

In nature, arsenopyrite commonly acts as a companion mineral of chalcopyrite. As the arsenic in arsenopyrite easily exudes during the smelting process, arsenic will not only pollute the environment but also seriously affect human health once it flows into the nature, so it is important to realize the separation of arsenopyrite and chalcopyrite. Flotation is the most efficient and commonly used means to separate these two minerals. As the floatability of arsenopyrite is similar to that of chalcopyrite, the two are usually separated using depressants to suppress arsenic and float copper. The commonly used inorganic depressants in the separation process of copper and arsenic have drawbacks such as poor selectivity, strong toxicity, and environmental pollution. Therefore, the development of a clean, efficient and non-toxic inhibitor is the key to the separation of copper and arsenic. Ethylenediamine tetramethylene phosphoric acid (EDTMP) was developed as a novel depressant of arsenopyrite to achieve the separation of arsenopyrite and chalcopyrite. Micro-flotation experiments and artificial mixture flotation tests verified the flotation performance of EDTMP, and the mechanisms of EDTMP adsorbed on arsenopyrite and chalcopyrite surface were revealed by Zeta potential, FTIR spectrum, and XPS measurements. The flotation experiments revealed that EDTMP could effectively depress the flotation of arsenopyrite without affecting chalcopyrite at pH = 10 and SIBX concentration of 200 mg/L, and the results of zeta potential and FTIR spectrum indicated that EDTMP is preferred to adsorb on arsenopyrite, which hindered the adsorption between SIBX and arsenopyrite. XPS results showed that EDTMP chemisorbed on arsenopyrite surface in the form of P-O-Fe bonds, while EDTMP weakly physisorbed on chalcopyrite surface. EDTMP was a novel arsenopyrite depressant, which was highly efficient, clean, and environmentally friendly compared to traditional depressants. [ABSTRACT FROM AUTHOR]

In order to fully understand the properties of a certain copper ore and develop a reasonable beneficiation process, a comprehensive analysis was conducted using chemical multi-element analysis, optical microscopy, MLA, and other methods to analyze the chemical composition, mineral types, structural characteristics, embedded features of the main minerals, and occurrence status of the main useful elements in the ore. It was found that the main useful elements in the ore were Cu and S, with grades of 1.73% and 20.81% respectively, as well as associated precious metal elements Au and Ag, with grades of 0.63 g/t and 5.46 g/t respectively. The main copper minerals were chalcopyrite, followed by tennatite and tetrahedrite, and the grain sizes of the copper minerals were above 0.020 mm and below 0.147 mm, mainly embedded in sulfide and vein minerals. The metal sulfides were mainly pyrite, with particle sizes mainly above 0.043 mm and below 0.417 mm, requiring fine grinding for individual dissociation during beneficiation. The gold minerals were mainly native gold and electrum, mainly in the form of fine particles, embedded in sulfide and vein minerals with a complex intergrown relationship and a relatively high difficulty in recovery. The distribution of silver elements was relatively scattered, most distributed in pyrite and copper minerals. Based on these results, it is recommended to use the "copper -- sulfur bulk flotation -- copper--sulfur separation flotation process" to process the copper ore, and to separate the bulk copper -- sulfur concentrate after re-grinding. Gold and silver can be recovered respectively in copper concentrate, sulfur concentrate, and tailings. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This is an article in the field of mineral processing engineering. The comprehensive recovery test of silver, gold and copper bearing sulfide concentrate was carried out. With isobutyl xanthate and sodium diethyl dithiocarbamate as a combined collector, calcium oxide as the depressant, 2# oil as a frother, which produced a concentrate approaching 16.66% Cu grade at 86.96% recovery, Au content of 278.95 g/t at 75.56% Au recovery and Ag content of 1848.74 g/t at 78.55% Ag recovery by a flotation process consisting of one stage of roughing，three stages of cleaning and two stages of scavenging was used to collect lead minerals. The comprehensive recovery of copper from sulfur concentrate has been effectively realized. At the same time, gold and silver are well enriched in copper concentrate, which is convenient for recovery and utilization, and the mineral processing index is ideal.

Sodium dithionite (Na2S2O4) is a widely used reducing agent to control pulp potential (Eh) and pyrite depressant in sulfide ore flotation. In this study, the pyrite depressant effect of sodium dithionite on gold ore flotation was investigated at pH 8 and pH 10.5 comparatively in terms of gold, chalcopyrite, and pyrite recoveries and grades. The presence of sodium dithionite resulted in a drop of approximately 50–70 mV in the Eh values, regardless of the studied pH values, confirming the reducing effect of sodium dithionite. The effects of sodium dithionite on gold and chalcopyrite grades and recoveries were quite limited, especially at pH 10.5. At pH 8, the utilization of sodium dithionite slightly decreased gold and chalcopyrite recovery and grades, while the decrease in pyrite recovery and grades was remarkable. Both pyrite recovery and grade were reduced from 79.5% to 54.7% and 15.3% to 10.7% by the utilization of sodium dithionite at pH 8. In conclusion, it is considered that the selective flotation of gold and chalcopyrite from pyrite can be achieved at a lower pH accompanied by a slightly reduced Eh by the utilization of sodium dithionite.

A comprehensive study of the Kyzyk-Chadr porphyry copper deposit included determination of the composition and spatial distribution of trace elements in ore-forming sulfide minerals over the ore-hosting rock volume. The study was carried out using the mass spectrometric analysis with laser ablation of the analyzed material. Steady qualitative and quantitative elements of a “hidden” mineralogical and geochemical zonality have been identified, that are expressed in variations in the concentration of trace elements and their ratios in pyrites and chalcopyrites over the volume of the ore-bearing porphyry copper stockwork. The identified regularities correlate with the established centrifugal vector and concentric pattern of the mineralogical ore-metasomatic zonality of the ore deposit.

We present an investigation into the magnetism exhibited by AMY2 compounds characterized by a chalcopyrite structure, where A can be Cu or Ag, M can be Sc, Ti, V, Cr, Mn, or Fe, and Y can be either S or Se. By substituting M atoms at the Ga position of AGaY2 compounds, the magnetic properties were calculated using the full potential linearized augmented plane wave method under the generalized gradient approximation and local spin density approximation with the WIEN2K code. The obtained spin-polarized results confirmed the presence of ferromagnetic and half-metallic (HM) properties in AMY2 compounds (A = Cu, Ag; M = Ti, V, Cr, Mn; Y = S, Se), wherein the HM property is preserved through p-d hybridization of p states of Y (S, Se) atoms with d (t2g) states of M (M = Ti, V, Cr, Mn) atoms, and minimal contribution of −s states of A (A = Cu, Ag) atoms. The total magnetic moments for AMY2 compounds were calculated as 1.00, 2.00, 3.00, and 4.00 µB/f.u. for M = Ti, V, Cr, Mn, respectively. For AFeY2 compounds (A = Cu, Ag; Y = S, Se), electronic band structures for both up spin and down spin states were identical, suggesting antiferromagnetic behavior at equilibrium, while AScY2 compounds (A = Cu, Ag; Y = S, Se) exhibited nonmagnetic properties at equilibrium. Overall, the accurate HM properties of AMY2 materials suggest promising prospects for their utilization in spintronics and magnetic storage device applications. [ABSTRACT FROM AUTHOR]

The article presents the synthesis and application of a novel collector, 5-methyl butylxanthate-1,2,4-triazole-3-thione (MBuXTT), for chalcopyrite flotation separation from pyrite. Various interfaces and surface characterization analysis methods were employed to study the flotation separation mechanism. The micro-flotation and contact angle experiments demonstrated a significant enhancement in the surface hydrophobicity of chalcopyrite following treatment with MBuXTT. Within the pH range investigated, MBuXTT effectively enriched chalcopyrite while separating it from pyrite. Compared to the traditional collector sodium butyl xanthate, MBuXTT exhibited superior selectivity and collecting ability towards chalcopyrite. Adsorption of MBuXTT on the chalcopyrite surface was found to be an endothermic-spontaneous chemisorption process. ζ-Potential analyses and UV spectra confirmed specific adsorption of MBuXTT on chalcopyrite rather than pyrite surfaces. Additionally, FTIR, XPS, and DFT calculations were conducted to explore the adsorption mechanism on the chalcopyrite surface, and the results indicated that MBuXTT-Cu complexes can be covered on the chalcopyrite surface with formation of Cu(I)-S and Cu(I)-N bonds along with release of H+ and oxidation product formation involving S–S bonds. [ABSTRACT FROM AUTHOR]

The Shuangjianzishan silver polymetallic deposit is located in the copper–tin–lead–zinc–silver polymetallic metallogenic belt in the Southern Great Xing'an Range, with silver resources of more than 18,000 t, which is the largest silver polymetallic deposit in Asia. Early studies concluded that the Shuangjianzishan deposit is typically an epithermal Ag-Pb-Zn deposit that lacks a high-temperature mineralization stage. In recent years, with the deepening of research, a large amount of Cu-Sn mineralization has been found in the deep part of the Shuangjianzishan deposit, but it is less studied. The laser-ablation inductively coupled mass spectroscopy (LA-ICP-MS) technique is used to investigate the distribution and substitution of trace elements in chalcopyrite and cassiterite. In this paper, the trace element study of chalcopyrite and cassiterite from the Shuangjianzishan deposit reveals that Sn, In, As, Se, Sb, and Tl mainly exist in chalcopyrite in isomorphic form, while Pb, Bi, and Ni mainly exist in chalcopyrite in the form of mineral inclusions. The enrichment of the high-temperature elements Sn and Se in chalcopyrite, and the deficit of the middle- and low-temperature elements Ga, Sb, etc., reflect that the chalcopyrite in the Shuangjianzishan deposit was formed in a middle- and high-temperature environment, and it also indicates that the early ore-forming hydrothermal solution may be rich in Sn. Fe, In, Co, and Ni mainly exist in cassiterite in isomorphic form, and the content of W in cassiterite is high. There are two main forms, one is isomorphic and the other is wolframite inclusion. Cassiterite has Fe-rich and W-U-poor characteristics, indicating that cassiterite from the Shuangjianzishan deposit was formed under relatively oxidized conditions, and the relative enrichment of elements such as Fe, W, Zr, and Hf indicates that the temperature of cassiterite formation was high. The elemental content and inter-ionic coupling relationships suggest that the cassiterite from the Shuangjianzishan deposit may have an elemental replacement mechanism of W6+ + Fe2+ ↔ 2Sn4+ or Fe3+ + OH− ↔ Sn4+ + O2−. The trace elements in cassiterite of the Shuangjianzishan deposit are rich in Fe and Mn and depleted in Nb and Ta, according to the Fe-W diagram, and the tin mineralization of the Shuangjianzishan deposit belongs to cassiterite–sulfide-type tin mineralization. Chalcopyrite Co/Ni ratios >1 are consistent with the characteristics of chalcopyrite genesis in hydrothermal deposits. [ABSTRACT FROM AUTHOR]

Designing effective strategies for mitigating energy crisis highlights a research gap in current solar cell technologies. This study explores the inherent physicochemical properties of thin films composed of copper gallium sulfide telluride (CuGa1−xCrx(S,Te)2) with chromium substitution, prepared through the chemical spray pyrolysis technique. The investigation showcases how the concept of intermediate band structuring contributes to enhancing solar cell efficiency. This enhancement can be attributed to the remarkable mobility (from 1.80 to 5.48 cm2 V−1 s−1) and conductivity (from 1.00 to 6.06 S cm−1) exhibited by pure and 0.1 chromium thin films, respectively. Notably, the Cr‐0.1‐substituted CGST film displays maximum photoresponsivity of 0.624 AW−1, an external quantum efficiency of 145%, and a detectivity of 2.37E10. The fabricated solar cell is subjected to theoretical simulation using solar cell capacitance simulator‐1D software, revealing an upward trend in efficiency from 7.13% to 11.23% with increasing Cr substitution from 0.025 to 0.1. This efficiency improvement can be ascribed to the reduction in bandgap (from 2.40 to 1.72 eV) and the creation of a sub‐band in CGST due to Cr incorporation, as substantiated by UV–vis and NIR spectroscopy. These outcomes suggest that Cr‐0.1‐substituted CGST holds promise as a potential thin film absorber material in solar photovoltaics. [ABSTRACT FROM AUTHOR]

This work focuses on the synthesis and properties of quaternary ZnSnP2-yAsy chalcopyrite solid solutions. Full miscibility of the solid solution is achieved using ball milling followed by hot press sintering. The measured electrical conductivity increases substantially with As substitution from 0.03 S cm−1 for ZnSnP2 to 10.3 S cm−1 for ZnSnAs2 at 715 K. Band gaps calculated from the activation energies show a steady decrease with increasing As concentration from 1.4 eV for ZnSnP2 to 0.7 eV for ZnSnAs2. The Seebeck coefficient decreases significantly with As substitution from nearly 1000 μV K−1 for ZnSnP2 to −100 μV K−1 for ZnSnAs2 at 650 K. Thermal conductivity is decreased for the solid solutions due to alloy phonon scattering, compared to the end members with y = 0 and y = 2, with the y = 0.5 and y = 1.0 samples exhibiting the lowest values of 1.4 W m−1 K−1 at 825 K. Figure of merit values are increased for the undoped solid solutions at lower temperatures when compared to the end members due to the decreased thermal conductivity, with the y = 0.5 sample reaching zT = 1.6 × 10−3 and y = 1 reaching 2.1 × 10−3 at 700 K. The largest values of the figure of merit zT for the undoped series was found for y = 2 with zT = 2.8 × 10−3 at 700 K due to the increasing n-type Seebeck coefficient. Boltztrap calculations reveal that p-doping could yield zT values above unity at 800 K in case of ZnSnAs2, comparable with ZnSnP2. [ABSTRACT FROM AUTHOR]