Copper Extraction Research Articles

Flotation extraction of copper and zinc ions with N-nonanoyl-N’-methanesulfonylhydrazine

The patterns of concentrating Cu(II) and Zn(II) ions from aqueous solutions with N-nonanoyl-N’-mesylhydrazine by the ion flotation method were studied, depending on the initial concentration of the collagents, the pH value of the solution, conditioning time, and temperature. Based on IR spectroscopy and elemental analysis data, a hypothesis about the composition of the floated compounds was made. It was shown that the extraction of Zn(II) is significantly dependent on the initial concentration of the metal and the conditioning time of the solution. A decrease in the extraction degree of the studied ions with an increase in the solution temperature was established, with this effect being more pronounced for Cu(II). The kinetics of the process were described using the classical first-order model; the obtained flotation rate constants for Zn(II) ions were five times higher than for Cu(II). The conditions for the selective separation of Cu(II) ions in collective flotation conditions were determined.

Assessing the Impact of Surface Blast Design Parameters on the Performance of a Comminution Circuit Processing a Copper-Bearing Ore

Open-pit mining remains the dominant method for copper extraction in current operations, with blasting playing a pivotal role in the efficiency of downstream processes such as loading, hauling, crushing, and milling. This study assesses the impact of surface blast design parameters on the performance of a comminution circuit processing a copper-bearing ore. The analysis focuses on important design parameters such as burden, spacing, stemming, and powder factor, evaluating their influence on the fragment size distribution and downstream comminution circuit performance. Using the Kuz-Ram model, four novel blast designs are compared against a baseline to predict the size distribution of rock fragments (X80). Key performance indicators throughput and specific energy consumption are calculated to evaluate the comminution circuit performance. Results demonstrated that reducing the X80 from 500 mm to 120 mm led up to a 20% increase in throughput and a 29% reduction in total specific energy consumption. Furthermore, achieving finer particle sizes through more intensive blasting contributed to a reduction in total operating costs by up to 12%. These findings provide valuable insights for optimizing blast design to improve comminution circuit performance, contributing to sustainable mining practices by reducing energy consumption, operating costs, and the environmental footprint of mining operations.

Fragment of the phase diagram of the Cu-CrSe2 system at room temperature

The chemical and electrochemical extraction of copper from CuCrSe2 was carried out at room temperature (RT). The compositions corresponding to the boundaries of the homogeneity region of CuyCrSe2 and Cu1-xCrSe2 were determined. X-ray diffraction (XRD) analysis demonstrated that within the composition range of y from 0 to 0.29, the phase with the structure of CrSe2 with space group P3¯m1 is stable. Furthermore, within the composition range of x from 0 to 0.33, the phase with the structure of delafossite CuCrSe2 (space group R3m) is stable.

Bacterial oxidation in the hydrometallurgical process of copper extraction from copper-containing ore

Copper extraction technologies are constantly being improved including chemical oxidants. However, chemical oxidants slightly increase the extraction. Thus, this study aims to increase copper extraction using bacterial oxidation as oxidizing reagent. It also compares extraction results between standard leaching with sulfuric acid and Acidithiobacillus ferrooxidans with amino acids nutrient medium. Ore from Zhezkazgan deposit that contains chrysocolla, malachite and iron hydroxide was used as a sample. The ore was dug from a 6m depth. The initial sample was crushed, grinded, mixed, and reduced before preliminary biooxidation by bacterial culture of Acidithiobacillus ferrooxidans. A mineralogical study of ore was conducted to confirm the copper contains, other compounds and phase composition as well. Acidithiobacillus ferrooxidans were cultured within the nutrient medium of amino acid. This study chooses amino acid serine L, glycine, and asparagine to provide optimum bacterial cell of A. Ferrooxidants. Results showed that preliminary biooxidation by bacterial culture of A.Ferrooxidans increased copper extraction significantly. Further, Acidithiobacillus ferrooxidans that grow in the nutrient medium containing L-Serine have the highest effect on copper extraction.

Innovative synergistic extraction of copper(II) from sulfate solutions using D2EHPA and Tri-n-octylphosphine oxide

Solvent extraction is a critical process in the copper extraction industry, offering an advanced method for separating and purifying copper from its ores. As industries aim for increased efficiency and sustainability, the significance of enhancing copper extraction methods is increasingly evident. The liquid-liquid extraction of copper(II) from sulphate medium with di(2-ethylhexy1) phosphoric acid (D2EHPA, HL) has been investigated in chloroform and 1-octanol at 25°C. The study examined the impact on several factors, including the equilibrium pH, extractant concentration, and the nature of diluent. The extracted copper(II) species were found to be CuL2.2HL in chloroform and CuL2 in 1-octanol and the extraction constants of these species were also estimated. The effect of the presence of tri-n-octyl phosphine oxide (TOPO) on the above extraction systems was also studied. A strong antagonistic effect observed during the extraction of copper(II), in the chloroform system is caused by a D2EHPA–TOPO interaction. In the 1-octanol system, the presence of TOPO may change the reaction stoichiometry of copper(II) and D2EHPA.

Effect of amino acids on the extraction of copper from sub-conditional raw materials

Effect of amino acids on the extraction of copper from sub-conditional raw materials

Significance of sustainable management practices and policy robustness in achieving carbon neutrality in KSA and UAE

Countries are under significant pressure from climate change due to high levels of carbon emissions, and they are working towards carbon neutrality (CN). This is particularly relevant for Saudi Arabia and the United Arab Emirates, which heavily rely on fossil fuels. Therefore, this study aims to suggest solutions for these countries. Specifically, it examines how sustainable management practices (SMP) impact CN. Additionally, it explores the moderating role of strong policies in the relationship between SMP and CN. To strengthen the study's findings, data were collected from 795 respondents across 244 firms in industries like oil, gas, iron, and copper extraction, selected based on their carbon emissions and potential for adopting sustainable practices. Using ordinary least squares regression, the study found that SMP has a significant positive effect on CN. Moreover, strong policies significantly enhance the relationship between sustainable practices and CN in both countries. Policymakers are encouraged to reinforce environmental regulations and offer incentives for adopting green technologies and practices. Effective policies can ensure the consistent use of SMP, leading to a significant reduction in carbon emissions.

Efficacy of using grape cane extracts against <i>Plasmopara viticola</i> under field conditions and their impact on the composition of berries and musts of <i>Vitis vinifera</i> L. cv. Riesling

Grapevine downy mildew caused by Plasmopara viticola is a deleterious vine disease currently controlled using synthetic and copper-based fungicides. Environmental concerns surrounding such fungicides necessitate sustainable alternatives like grape cane extracts. However, studies into their efficacy and effects on the product remain limited. This study aimed to assess the open-field efficacy of a novel grape cane extract formulation, alone and combined with a copper agent, against downy mildew, and to examine its impact on berry and must composition. The results were compared to standard fungicides frequently used in integrated and organic viticulture. In 2022, the grape cane extract formulation reduced downy mildew severity by 78 % on berry clusters, comparable to the maximum acceptable dose of copper for organic farming in Germany (3 kg/ha/a). Combining the grape cane extract with the copper agent was more effective than the copper agent alone, but not more effective than the grape cane extract alone. In 2023, disease development was marginal, despite artificial inoculation. Compositional differences detectable by FTIR were insignificant between musts derived from all treatments, increased copper levels were observed whenever copper had been applied. The phenolic content in freeze-dried, de-seeded berries of 2022 was significantly lower after copper (14.6 mg/g dry weight DW) and grape cane extract treatments (6.6 mg/g DW) when compared to the control (36.1 mg/g DW), with discrepancies in stilbenoid and flavan-3-ol levels in particular, as analysed by HPLC-DAD. However, these differences were not confirmed in 2023, with results showing no correlations between different treatments and phenolic contents. These findings suggest that applications of the phenolic grape cane extract do not lead to artificially altered levels or relevant residues of the active constituents; i.e., the phenolic compounds in the product. In brief, grape cane extracts might represent a promising natural alternative to controlling grapevine downy mildew, particularly in organic viticulture, which, to date, heavily relies on (eco-)toxic copper-pesticides. Further multi-year studies including wine analyses are warranted to follow the entire flow towards the final product.

Effect of Curing Time and Ferric Chloride on a Copper Concentrate with a High Arsenic Content

As a result of changes in copper mineralogy, various treatment options for copper sulfides have been explored, including pretreatment processes aimed at enhancing material permeability and improving the dissolution of valuable minerals. Despite its significance, this topic has only recently gained attention. In this research, a copper concentrate with a high arsenic content was studied, with enargite (Cu3AsS4) as the main mineral phase. The objective was to evaluate the effect of pretreatment on copper extraction efficiency prior to leaching. Three key variables were investigated: curing time (0, 5, 10, and 15 days), H2SO4 dosage (0, 70, 140, and 210 kg/t), and FeCl3 concentration (0, 0.5, 1, and 1.5 M). The sample was characterized both before and after pretreatment, revealing the formation of new species such as CuSO4·5H2O and Cu2Cl(OH)3 under optimal conditions of 15 days curing time, 70 kg/t of H2SO4, and 1 M FeCl3. Copper extraction solely through curing reached 20.79%. The analysis suggests that curing time is the most influential factor in the process, accounting for 46% of the overall contribution. In comparison, sulfuric acid and ferric chloride contribute less, with 20% and 10% contributions, respectively.

Mineralogical Characterisation of Copper Slag and Phase Transformation after Carbocatalytic Reduction for Hydrometallurgical Extraction of Copper and Cobalt

Copper smelting slag is a significant potential resource for cobalt and copper. The recovery of copper and cobalt from copper slag could significantly augment the supply of these metals, which are essential to facilitating the transition to green energy while simultaneously addressing environmental concerns regarding slag disposal. However, the complex mineral composition of copper slag poses an enormous challenge. This study investigated the mineralogical and chemical characteristics of copper slag, which are vital for devising the most effective processing techniques. XRD and FESEM-EDS were employed to examine the morphologies of copper slag before and after the reduction process. The effects of borax and charcoal (carbocatalytic) reduction on phase transformation were evaluated. The XRD analysis revealed that the primary phases in the copper slag were Fe2SiO4 and Fe3O4. The FESEM-EDS analysis verified the presence of these phases and yielded supplementary details regarding metal embedment in the Fe2SiO4, Fe3O4, and Cu phases. The carbocatalytic reduction process expedited the transformation of copper slag microstructures from crystalline dendritic to amorphous and metallic phases. Finally, leaching experiments demonstrated the potential benefits of carbocatalytic reduction by yielding high extractions of Cu, Co, and Fe.

INNOVATIVE METHODS FOR PROCESSING COPPER ORES IN KAZAKHSTAN: A COMPREHENSIVE APPROACH TO ENHANCING THE EFFICIENCY OF VALUABLE COMPONENT EXTRACTION

This article presents an innovative approach to processing copper ore from one of the deposits in Kazakhstan, aimed at enhancing the efficiency of copper extraction from materials with a complex mineral composition. The described methodology includes several key stages: comprehensive analysis of the ore's material composition, gravity and flotation beneficiation, as well as hydrometallurgical processes. During the study, the ores underwent preliminary preparation, including crushing and grinding to the required fineness. Experiments on gravity and flotation beneficiation demonstrated that optimizing the parameters of these processes significantly increases the yield of copper concentrate. Additionally, sulfuric acid leaching conducted showed high efficiency in extracting copper from the ground ore. The research results confirm that a comprehensive approach to copper ore processing ensures high efficiency in extracting valuable components and opens up prospects for the sustainable and economically viable utilization of complex copper ores

Moderate permeability enhanced microbial community turnover and copper extraction during bioleaching of low-grade copper ores

Heap bioleaching is one of the most promising technologies for extracting valuable metals from low-grade ores. However, the effects of permeability of the heap on microbial community and bioleaching efficiency remain unclear. In this study, heap bioleaching systems with different permeability were constructed. Despite the high content of larger particles had better permeability (0.25 cm/s) and oxygen transfer efficiency (0.14), there was a 25 % decrease in copper extraction compared with the moderate permeability group (81.2 %), while low permeability (0.025 cm/s) could cut the extraction in half (48.5 %). The fine profiles of microbial communities based on relatively and absolutely quantitative technologies suggested that permeability significantly affected microbial diversity, biomass, and composition. Microbial community evenness was crucial to improving extraction than biomass. Additionally, Thermoplasmatales except for Acidiplasma and Ferroplasma played vital roles in bioleaching. This study highlighted the delicate trade-off of particle size-mediated permeability for intensifying bioleaching efficiency of low-grade copper ores.

Development of an Enhanced Method for Copper Extraction from Sulfuric Acid Solutions

Development of an Enhanced Method for Copper Extraction from Sulfuric Acid Solutions

Design and Comparison of Fractional-Order Controllers in Flotation Cell Banks and Flotation Columns Used in Copper Extraction Processes

This work explores efficiency improvements in the copper flotation stage, a complex nonlinear, multivariable process subject to numerous perturbations. The primary objective is to design a fractional-order PID (FOPID) control strategy and a fractional-order model reference adaptive control (FOMRAC) system. The parameters for these controllers are optimized using the particle swarm optimization (PSO) algorithm with an objective function tailored to the control goals. This study employs models of both a bank series of five flotation cells and a flotation column. Their performance results are compared against traditional controllers, such as an integer-order PID and MRAC. The findings reveal that fractional-order controllers offer notable advantages over their integer-order counterparts, showing improved performance metrics with minimal changes to the existing control framework. This research highlights the effectiveness of fractional control in enhancing flotation processes and introduces a novel application of fractional control techniques in this area.

The Testing Results of ACORGA, LIX Extractants and CR60 Crud Mitigation Reagent Influence during SX-EW Copper Extraction

Research analysis reveals factors influencing third-phase crud formation and composition during metal extraction, including solution composition, solid suspensions, organic compounds, colloidal compounds (e.g., silicic acid), and extractant purity. Compositional analysis of copper-containing sulfuric acid solutions (1.25 g/dm3 copper) identifies principal sulfate-forming components. Copper extraction was studied using extractants LIX 984N, ACORGA M5774, and M5640 at different ratios of the organic phase to the aqueous O:A (from 1:2 to 1:10). Suppressive impact of 10 vol.% CR60 additive on third-phase crud formation during copper extraction with LIX 984N, ACORGA M5774, and M5640 is analyzed, with ACORGA M5774 being the most effective. Physicochemical analysis characterizes CR60’s active substance as poly(sodium 4-styrenesulfonate) with steel-suppression properties, and its structural formula is determined. Optimal copper extraction conditions establish ACORGA M5640’s 24% efficiency, followed by ACORGA M5774 at 15%. CR60 reduces crud formation, with 5 cm3 of ACORGA CR60 added to sulfuric acid solution reducing interfacial crud formation by 2–3 times. Optimal extraction parameters include 1:2 O:A ratio, 20 ± 5 °C temperature, 5 cm3 CR60 additive, 5 min process duration, and 1-day settling time. ACORGA M5774 (10 vol.% in kerosene) is recommended as an extractant, with 2–3 stages of countercurrent extraction.

Copper and Lithium Industrialization by Major Producing Countries for Mining Sustainability

This research objective is to analyze the prospects of copper and lithium industrialization for the mining sustainability of the world's major producing countries. An expo-facto design was used based on a documentary analysis, considering the world ranking of the top copper-producing countries, where Chile, Peru, China, and the Democratic Republic of Congo stand out, and regarding lithium production, Australia, Chile, China, and Argentina stand out. On a global level, the presence of South American countries with mining resources in exploration and extraction is relevant; in contrast, China, a mining country, not only extracts natural resources but has advanced in the value chain with competitive advantages and consequent economic development; for its part, the DR of Congo (Africa), has ascended in the copper extraction ranking. The motors and electrical systems of electromobility vehicles are manufactured with copper and the batteries with lithium, which contributes to the mitigation of greenhouse gas emissions and thereby to environmental sustainability. Furthermore, the correlation between copper and lithium demand for electric vehicles in a 2050 zero-emission scenario is strong. There are social conflicts, mainly over the use of water; therefore, it is necessary to implement mining policies that lead to sustainable development.

Application of soil amendments to reduce the transfer of trace metal elements from contaminated soils of Lubumbashi (Democratic Republic of the Congo) to vegetables

The extraction of copper and cobalt from mines has led to the contamination of agricultural soils by trace metal elements (TMEs) (e.g. Cu: 204 to 1355 mg/kg). The mining industry is one of the sources of metal discharges into the environment, contributing to water, soil, and air contamination and causing metabolic disorders in the inhabitants of the city of Lubumbashi (R.D. Congo). This study assessed the effectiveness of organocalcareous soil improvers applied to TME-contaminated soils to reduce their transfer to plants. Following a factorial design, increasing doses of organic soil improvers (chicken droppings and sawdust) and agricultural lime were applied to the soils of three market gardens (high, medium, and low Cu contamination). The experiment was monitored for 60 days. Soil physicochemical properties (pH, TOC, and total and available copper, cobalt, lead, cadmium, and zinc (mg/kg)) were determined for the three gardens and in the vegetable biomass. The daily consumption index of the vegetables was determined based on total TME content. The results show that organocalcareous soil improvers did not promote plant growth and survival on soils with high and medium levels of copper contamination. However, on soils with low copper content, organocalcareous soil improvers improved germination and plant survival and reduced the transfer of metals from the soil to the plants. The best germination and plant survival rates were obtained with the lightly contaminated market garden. In addition, the organo-limestone amendments applied to the soils slightly increased the soil pH from acidic to slightly acidic, with pH values ranging from (5.43 ± 0.07 to 7.26 ± 0.33). The daily vegetable consumption index obtained for cobalt in the low-contaminated garden ranged from (0.029 to 0.465 mg/60 kg/day), i.e. from 0.5 to 8.45 times higher than the FAO/WHO limit, unlike the other trace metals (Cd, Cu and Pb) for which the daily consumption index found was lower than the FAO/WHO limit. Organocalcareous soil improvers can only be applied to soils with low levels of TME contamination, but for soils with medium to high levels of metal contamination, new soilless production techniques such as hydroponics or bioponics are needed.

Cu(Ⅱ)-EDTA degradation and copper recovery from wastewater in wide pH ranges by an electrooxidation-capacitive deionization system

The treatment and recovery of metal resources from complex industrial wastewater has posed significant challenges due to the presence of multiple heavy metal ions, heavy metal complexes, and acidic conditions. In this study, a novel electrooxidation-capacitive deionization (EO-CDI) system was proposed, which ingeniously harnessed the unheeded Faraday side reaction in capacitive deionization for simultaneous degradation and recovery of copper complexes from wastewater through two electrode integration. Specially, the cathode CuS0.78Se0.22 synthesized through the anionic Se-substitution strategy exhibited a remarkable adsorption capacity up to 672.02 mg/g for Cu ions, outstanding selectivity and stability, particularly in acidic environments. The water oxidation process occurring at the activated carbon anode played a crucial role by generating active species that contribute to the degradation of Cu(Ⅱ)-EDTA, which leaded to the release of copper ions, facilitating their subsequent recovery. Cyclic experiments further confirmed the excellent cyclic stability of the hybrid EO-CDI system, along with its impressive performance in copper extraction when applied to real industrial wastewater. This innovative approach offered promising prospects for addressing the challenges associated with the treatment of complex industrial wastewater and the recovery of valuable metal resources.

Recovery of copper from ammonia–ammonium chloride leach liquor using sterically hindered beta-diketone

In this study, the recovery of copper from ammonia–ammonium chloride (NH3–NH4Cl) leach liquor using sterically hindered beta-diketone (β-diketones), a well-known extractant, was investigated. The experimental approach entails studying how various factors, including extraction time, concentration of the extractant, pH, phase ratio, and temperature, impact the effectiveness of copper extraction. The most favourable conditions for extracting copper from ammoniacal solutions containing 871.27 mg/L Cu2+, 1.75 mol/L NH3, and 0.5 mol/L NH4Cl were determined. Optimal copper extraction was achieved through a one-stage solvent extraction process at a phase ratio of 1 : 1, utilising sulphonated kerosene containing 0.25 mol/L of β-diketones. This extraction process lasted for 10 min and yielded a copper extraction efficiency of 75.10%. Additionally, a stripping ratio of 98.52% was achieved from the loaded organic phase through a one-stage stripping procedure at a phase ratio of 1 : 1, conducted at a temperature of 298 ± 0.5 K.

Impact of mechanical activation and mechanochemical activation on microstructural changes, leaching rate and leachability of natural chalcopyrite

The influence of mechanical activation (MA) and mechanochemical activation (MCA) with Fe and Fe2O3 on the microstructural changes, leachability and leaching rate of natural chalcopyrite was investigated and compared. MCA pretreatments were carried out by chalcopyrite co-milling with Fe and Fe2O3 for 20 and 50 min. The XRD analysis indicated that even after 50 min MA and MCA, constituent phases of chalcopyrite, Fe and Fe2O3 could be detectable beside the newly formed bornite. Regarding the peak broadening and peak intensity reduction, MCA generally intensified the microstructural changes of chalcopyrite in comparison with MA. The microstructural study performed by the Rietveld method also proved that all microstructural parameters changed in favor of reactivity, such that the amorphization degree and microstrain were increased to 96 % and 0.164 (%), respectively, while crystallite size was reduced to 14.6 nm after 50 min MCA of chalcopyrite with Fe2O3. It could be concluded from the leaching tests that MCA along with Fe and Fe2O3 addition could promote the leachability and leaching rate of chalcopyrite, as compared to MA and nonactivated chalcopyrite. Although both the MCA of chalcopyrite with Fe and Fe2O3 could enhance copper extractions in the 1 M sulfuric acid leaching tests at 80 °C, Fe addition was slightly more effective than Fe2O3. The results obtained from the kinetic study also revealed that the leaching mechanism of nonactivated chalcopyrite, mechanically activated chalcopyrite and mechanochemically activated chalcopyrite with Fe2O3 changed from diffusion control to chemical control due to MCA with Fe. Finally, the combination of kinetic and microstructural studies proved that all microstructural parameters, except for the microstrain parameters of chalcopyrite MCA with Fe2O3, could be effective in chalcopyrite reactivity promotion.