Selective Extraction Of Copper Research Articles

Process optimization and mechanism for the selective extraction of copper(ii) from polymetallic acidic solutions using a polymer inclusion membrane (PIM) with Mextral®5640H as the carrier.

This study introduces a novel approach by integrating solvent extraction and polymer inclusion membrane (PIM) separation technologies to engineer an innovative PIM membrane material for the selective separation and enrichment of strategic metals, particularly copper, from polymetallic acidic solutions. The primary objectives were to streamline the technological process, reduce production costs, and enhance separation coefficients between copper and other metals. The optimal extraction conditions were determined as a mass fraction of Mextral®5640H : PVC : NPOE = 3 : 3 : 4, extraction temperature of 35 °C, and 0.9 mol L-1 H2SO4 in the stripping solution. Under these conditions, we achieved remarkable extraction efficiencies, with copper reaching 100%, and the separation coefficients between Cu2+ and Ni2+, Co2+, and Zn2+ exceeding 106. To elucidate the substantial differences in extraction performance between Cu2+ and the other metals (Ni2+, Co2+, and Zn2+), we employed an integrative analytical approach that combines FT-IR spectroscopy, BET analysis, and theoretical calculations. All extracted complexes demonstrated molecular sizes compatible with PIMs, underscoring the critical role of stability and back-extraction performance in the selective extraction of these metal ions.

Negative-carbon recycling of copper from waste as secondary resources using deep eutectic solvents

Copper plays a crucial role in the low-carbon transformation of global communities with prevalent use of electric vehicles. This study proposed an environmentally friendly approach that utilizes a deep eutectic solvent (DES), choline chloride-ethylene glycol (ChCl-EG), as green solvent for the selective extraction of copper from scrap materials. With hydrogen peroxide as an oxidizing agent, the copper species from the printed circuit boards (PCBs) scraps were efficiently leached by the DES through oxidation-complexation reactions (conditions: 25 min, 20 °C, and 5 wt% H2O2). Molecular dynamics and density functional theory were performed to simulate the intricate cascade of interactions between copper species and hydrogen bond donors/acceptors of DES, providing insights into the mechanistic processes involved. Copper was selectively recovered from the DES leachate containing impurities (e.g., Pb2+, Sn2+, and Al3+) through electrodeposition via a diffusion-controlled reaction under a constant potential mode. A comprehensive life cycle assessment of the process demonstrated that the utilisation of DES in the extraction of copper from waste PCBs could result in significant reduction in carbon dioxide emissions (−93.6 kg CO2 eq of 1000 kg waste PCBs), thus mitigating the carbon footprint of global copper use through the proposed solvometallurgical recycling process of secondary resources.

Eco-friendly recovery of base and precious metals from waste printed circuit boards by step-wise glycine leaching: Process optimization, kinetics modeling, and comparative life cycle assessment

Glycine as a green alternative to cyanide for gold leaching is a promising reagent to put a curb on the environmental footprints of conventional hydrometallurgical processes. This work was designed to investigate the step-wise glycine leaching of the base and precious metals from waste printed circuit boards (WPCBs) as one of the most dominant and problematic e-wastes in today's world. Using response surface methodology, selective copper extraction reached 99.96% recovery at the optimum condition of 0.5 M glycine, 1% v/v H2O2, 20 g/l pulp density, and ambient temperature. Copper sulfide was then recovered from the leach solution via precipitation by sodium hydrosulfide. Gold leaching in the glycine + permanganate system was thoroughly studied with an emphasis on the process's kinetics mechanisms. It was revealed that gold leaching in the glycine and permanganate system starts with a rapid phase followed by a slower chemically controlled phase. At the optimum condition of 4 g/l glycine, 2 g/l potassium permanganate, and room temperature, 96.17% of the gold was selectively extracted. By using 3 g/L activated carbon, about 100% of the gold was separated from the leach solution. Comparative life cycle assessment revealed that in the proposed process, the main contributor to most of the environmental impact categories is glycine. Replacing the first step of glycine copper leaching with nitric acid can substantially reduce the environmental footprints of the process to a lower level than many other proposed recycling routes.

Selective Copper Extraction from Spent Lithium-Ion Batteries

This paper is dedicated to the investigation of selective copper extraction from the black mass of lithium-ion batteries (LIBs) using ammonium sulfate. Thermodynamic analysis performed with the use of Pourbaix diagrams allowed to compare and predict the area of stable copper and cobalt ammine complexes, determine operating pH range (8.7-9.7) for solutions. Concentrations of sodium hydroxide and ammonium sulfate were defined experimentally allowing to achieve high copper extraction (82-87 %) at low cobalt recovery into solutions (0.25-0.52 %). By variation of main leaching parameters optimal process conditions were determined: (NH4)2SO4 45 g/dm3, NaOH 9 g/dm3, 25 С, l : s = 5 : 1, 120 minutes.

Employing magnesium-lead melt for synergetic and selective extraction of copper from copper-cobalt alloy

This research aims to extract Cu from Cu-Co alloy with high efficiency and selectivity by employing binary Mg-Pb melt. The optimal conditions for the extraction of Cu were determined. The results showed under optimal conditions, 96.5% of Cu in the Cu-Co alloy could be selectively extracted after treatment at 800 °C for 1 h, with the extraction rates of only 0.2% Fe, 0.6% Co, and 1.4% Si. The dissolution mechanism involved the counter diffusion of Mg/Pb and Cu across the diffusion zone of the Cu-Co alloy, and Mg in the binary Mg-Pb melt played a major role in the selective dissolution of Cu, especially at the dissolution forefront. The rate-controlling step of the extraction was dominated by the interfacial reaction.

Extraction of copper from the mining industry recirculation waters

Acidic recirculation water and effluents generated by the mining industry and bearing heavy metals can have a significant environmental impact on this region. Due to high concentrations of non-ferrous metals (5.2–300 mg/dm3 Cu; 50–450 g/dm3 Zn), such waters can be used as a raw material for producing concentrates for further recovery of metals from them. This study looked at the recirculation water of the Soryinsk tailings pod, the underspoil waters of the Novo-Shemursk deposit and the Urupsky GOK mine waters. The aim of the study is to develop a process for selective extraction of copper into a product that can be further processed into a final product. The most common techniques used to remove ions of heavy non-ferrous metals from industrial wastewater include neutralization techniques. In this case, however, a considerable share of non-ferrous metals get wasted. At the same time, reagent techniques (e.g. sulphidation in the acidic pH region) enable to selectively extract such metals into concentrates that can then be used in the conventional non-ferrous metal production technology. A sulphur solution in sodium hydroxide was used as a sulphidizer for selective extraction of copper from polycomponent wastewater. The sulphur solution was produced at the temperature of 115–120 oC, the mass ratio NaOH:S of 1:1 and the sulphur concentration of 350 g/dm3. Use of sulphur dissolved in sodium hydroxide helped extract copper in the form of sulphides from complex solutions. It resulted in a high recovery of copper (94–99.9%) and a high-concentration copper concentrate (8.9–27.5%). It was found that iron (III) interacts with sulphide ions forming elemental sulphur, which can be reused for conditioning of copper concentrate in sodium hydroxide. Thus, the sulphur can be reused and the concentration of copper can be increased to 24%. The physical properties of particles in copper sulphide concentrates determine the high rate of solid phase precipitation from the slurry. Sulphide particles are characterized with a high negative charge (–80…–100 mV) and the size of the 90% of the particles reaching 68.9 μm. The authors developed a process flow diagram for extracting copper from low-grade complex solutions. The process involves regular addition of sulphidizer to the existing water flow, detention of a solid copper phase and, when necessary, conditioning of copper concentrate.

Selective room-temperature leaching of copper from mechanically activated copper smelter slag

Herein, the room-temperature sulfuric acid leaching of copper smelter slag powder in the presence of potassium dichromate was investigated, resulting in the selective extraction of copper with its separation from zinc and iron. To enhance the extraction of copper, mechanical activation in the planetary ball mill and attritor was used. The Taguchi method was applied to determine the optimal conditions for both mechanical activation and leaching. For mechanical activation in the attritor, a rotation speed of 1200 rpm, ball-to-powder ratio of 40 and milling time of 75 min were ideal. Under these conditions, the specific surface area (SBET) could be increased from 1.7 m2/g, for the starting slag, to 59.4 m2/g. According to ANOVA, the most important factor is the rotation speed. For comparison, the slag was subjected also to planetary ball milling using the same conditions and a specific surface area of 116 m2/g was obtained. Leaching conditions that maximize copper recovery and, independently, copper selectivity, were also found. The maximum copper recovery was 87.3%, while the maximum copper selectivity was 97.9%. The most influential parameters in leaching were the concentration of K2Cr2O7 and the liquid-to-solid ratio. The copper selectivity is attributed to better solubility of chalcopyrite (CuFeS2) in comparison with zinc ferrite (ZnFe2O4) and fayalite (FeSiO4) containing the other metals. This study provides a statistical approach for planning the experiments of pretreatment and leaching to efficiently recover valuable metals from secondary raw resources in an environmentally interesting fashion by using low concentrations of leaching agents and mechanical pretreatment.

Simple and complete separation of copper from nickel in the ammoniacal leach solutions of metal coated ABS plastic waste by antagonistic extraction using a mixture of LIX 84-I and TBP

A solvent extraction-based method using mixed extractants of LIX 84-I and TBP has been developed for complete separation of copper from nickel in the ammoniacal leach solutions of ABS plastic waste. The selective separation of copper was facilitated by the antagonistic effect of the extractants on depressing nickel extraction. The FTIR spectra indicated the possibility of hydrogen bonding between H-atom of hydroxyl group of LIX 84-I and O-atom of phosphoryl group of TBP while lowering the availability of extraction sites of LIX 84-I and increasing the bulky alkyl groups in the organic phase, causing the antagonism desired for Ni extraction. A McCabe-Thiele diagram of copper exhibited that a four counter-current stage at operational conditions of 0.5 M LIX 84-I + 0.5 M TBP, aqueous/organic (A/O) phase ratio of 1.3/1 and 25 °C was required to achieve the quantitative selective extraction of copper from real solution of ABS plastic waste with Cu2+ and Ni2+ concentration of 8.14 and 2.57 g/L, respectively, without any coextraction of nickel to the organic phase. Complete stripping and enrichment of copper was reached after a three counter-current stage using 2.0 M H2SO4 solution at O/A phase ratio of 2/1; copper in the stripped solution was found to be 21.03 g/L. Recycling of the mixed extractants for reuse in copper and nickel separation was demonstrated, and thereafter, a recommended flowsheet of recycling metals from ABS plastic waste was given. The antagonistic extraction system comprising of oxime-based extractant, LIX 84-I, and organophosporus extractant, TBP, presented in this study shows a potential for sustainable metal separation process.

Technological experiments of joint smelting of lead intermediate products, recycled materials and high-sulfur copper-zinc concentrate

The purpose of this work is to improve the technological indicators of the existing mine contractile smelting technology by joint smelting of intermediate products, recycled materials of lead production with high-sulfur copper-zinc concentrate. It is established that during the smelting of copper-zinc concentrate which is difficult to process, high selective extraction of copper into matte and zinc into slag is achieved in one stage. The method consisted in the joint smelting of lead intermediates and high-sulfur copper-zinc concentrate in an electric furnace at a temperature of 1250 ° C under conditions of sequential blowing of the melt with air, then with natural gas. It is established that when the melt is purged with air and natural gas for 20 minutes, an equilibrium distribution of metals between the melting products is achieved. It is shown that simultaneous use of copper-zinc concentrate as a sulfidizer reduces the content of copper and lead in slag, increases the extraction of arsenic and antimony into the dust. Consumption of coke and quartz flux is reduced in comparison with the existing technology from 6.7 to 2.5% and from 12.5 to 2.8% of the initial feed weight, respectively, which significantly reduces material and energy costs of the process. As a result of extensive laboratory testing, the optimum composition of the new charge has been selected. Metal distribution between smelting products of the new charge with addition of 30% of high-sulfur copper-zinc concentrate was established. High recovery of copper to the matte up to 94.8%, against 83.7% according to the existing technology; lead to the rough lead - up to 93.6%, against 70.8%; zinc to the slag - up to 94.7%, against 83.7%; arsenic to the dust - up to 91%, against 69.5% and antimony to the dust - up to 92.3%, against 60.0% according to the existing technology.

Use of Ammonia Salts in Selective Copper Extraction from Tailings

Tailings (flotation waste) that is formed during copper production may be considered in the class of valuable wastes due to the amount of copper it contains. Owing to the decreasing grade values in copper ores, utilization of wastes such as tailings that carry certain amounts of copper as secondary sources has become a necessity in both the economic and environmental sense. This study investigated the usage conditions of five different ammonia salts as leaching reactants for the purpose of selective extraction of copper from tailings. For this purpose, the effects of parameters such as leaching temperature and leaching time were examined at different concentrations of ammonium hydroxide, ammonium carbonate, ammonium nitrate, ammonium chloride, and ammonium persulfate. The copper extraction efficiency in the case of using the aforementioned salts by themselves were listed as (NH4)2CO3 (73%) > (NH4)2S2O8 (69%) > NH4OH (64%) > NH4Cl (42%) > NH4NO3 (40%). The highest copper extraction efficiency was obtained in the leaching process that was conducted with the solutions obtained by mixing ammonia salts in the best conditions. Accordingly, as a result of 6 h of leaching at 30 °C in the presence of 22.5% NH4OH and 100 g/L (NH4)2S2O8, 91.47% of the copper was transferred into the solution, while iron was not transferred. The obtained results showed that copper could be selectively recovered from tailings.

Selective Copper Recovery with HCl Leaching from Copper Oxalate Material

In this study, recovery of copper from solid material (obtained by leaching of chalcopyrite with oxalic acid in the presence of hydrogen peroxide) with a copper oxalate structure was carried out selectively using HCl. The chemical composition of the solid was as 29.3%, 9.7%, and 13.3% for Cu, Fe, and S, respectively. Selective recovery of copper by degrading the copper oxalate structure with a low-solubility product (Ksp = 4.43 × 10−10) was performed by conventional leaching in the presence of HCl. The optimum leaching conditions were determined as 5 M of HCl concentration, 318 K of leaching temperature, 120 min of leaching time, 25 ml/g of liquid–solid ratio and 400 rpm of stirring speed. Under these conditions, approximately 77% of copper and 3% of iron were taken into the solution. According to the characterization of the leach residue that was obtained, the oxalate structure was degraded. Moreover, the results of XRD analysis showed that the sulfur (S) and cubanite (CuFe2S3) phases were mostly observed in leaching residues, and this was supported by the SEM-EDX data. Based on the results, it may be stated that selective copper extraction can be obtained from a chalcopyrite concentrate by a two-step leaching method using a conventional hydrometallurgical technique.

A Simplified Extractive Metallurgy Exercise to Demonstrate Selective Extraction of Copper

A laboratory activity is described for senior high school or first year undergraduate level students that illustrates key concepts linked to extractive metallurgy. This experiment demonstrates preferential binding of a methoxyphenolic oxime ligand to Cu2+ in the presence of other transition metal ions in aqueous solution. The students are tasked to investigate the importance of the spatial relationship between the oxime and phenol group of two potential ligands by performing a series of short and simple tests. The objective is achieved by identifying which methoxyphenolic oxime ligand selectively and rapidly forms an isolable precipitate with Cu2+ ions. Only one of the potential ligands exhibits a clear preference for binding to Cu2+, and this can easily be identified visually (and confirmed by UV–visible spectroscopy if desired). The experiment has successfully been employed as part of an extracurricular laboratory course involving groups of 25–30 high school students.

Selective copper extraction by multi-modified mesoporous silica material, SBA-15

Selective copper (Cu) recovery from wastewater mitigates environmental pollution and is economically valuable. Mesoporous silica adsorbents, SBA-15, with amine-grafting (SBA-15-NH2) and manganese loading along with amine-grafting (Mn-SBA-15-NH2) were fabricated using KMnO4 and 3-aminopropyltriethoxysilane. The characteristics of the synthesized adsorbents were evaluated in detail in terms of its crystal structure peaks, surface area and pore size distribution, transmission electron microscope and X-ray photoelectron spectroscopy. The results established the 2.08mmol/g of Cu adsorption capacity on Mn-SBA-15-NH2. Furthermore, in a mixed heavy metal solution, high selective Cu adsorption capacity on Mn-SBA-15-NH2 (2.01mmol/g) was achieved while maintaining 96% adsorption amount as that of a single Cu solution. Comparatively, Cu adsorption on SBA-15-NH2 decreased by half due to high competition with other heavy metals. Optimal Cu adsorption occurred at pH5. This pH condition enabled grafted amine group in Mn-SBA-15-NH2 to form strong chelating bonds with Cu, avoiding protonation of amine group (below pH5) as well as precipitation (above pH5). The adsorption equilibrium well fitted to Langmuir and Freundlich isotherm models, while kinetic results were represented by models of linear driving force approximation (LDFA) and pore diffusion model (PDM). High regeneration and reuse capacity of Mn-SBA-15-NH2 were well established by its capacity to maintain 90% adsorption capacity in a multiple adsorption-desorption cycle. Cu was selectively extracted from Mn-SBA-15-NH2 with an acid solution.

Optimization of selective copper extraction from chalcopyrite concentrate in presence of ammonium persulfate and ammonium hydroxide

The dissolution of copper and iron from chalcopyrite concentrate in the presence of ammonium persulfate (APS) and ammonium hydroxide was investigated under atmospheric leaching conditions. Experiments were designed by central composite design (CCD). Under the optimum leaching conditions ((NH4)2S2O8 concentration = 328 g/L; NH4OH addition = 16vol%; leaching temperature = 321 K (48°C); leaching time = 120 min; liquid-to-solid ratio = 16; stirring speed = 400 r/min), selective leaching was achieved. 98.14% of the copper was leached, whereas iron did not pass into the solution. X-ray diffraction analysis of the leaching residue showed that iron compounds were predominant. Given the leaching results, the fact that the leaching process does not include uneconomical leaching stages such as extended milling/mechanical activation or high pressures/temperatures, and the low copper dissolution conditions, the attained selective leaching yield may be remarkable.

Selective extraction of copper from Cu-Zn sulfate media by new generation extractants

The selective recovery of copper(II) from Cu-Zn sulfate solutions using solvent extraction and N,N-dialkyl-N′-hydroxypyridine-2-carboximidamides as extractants was investigated. Three compounds were synthesized and their extractability toward copper(II) and zinc(II) was studied. The influence of process parameters such as the pH of aqueous phase, shaking time, diluent type and also extractant’s structure and concentration on efficiency of both metals ions extraction was presented. Results indicated that the equilibrium pH and type of the organic diluent had the biggest impact on the copper(II) extraction efficiency, its selectivity over zinc(II), and the stoichiometry of formed copper complex. Obtained experimental data were used to develop a method of copper(II) extraction from Zn-Cu sulfate solution composed of 40.9 g/L Zn(II) and 1.2 g/L Cu(II). A flowsheet was tested in laboratory-scale reactors and the conducted test confirmed the possibility to selective recover of Cu(II) over Zn(II), and the concentration of Cu(II).

Selective Solid Phase Extraction of Copper from Different Samples using Copper Ion-Imprinted Polymer

Ion imprinted polymer (IIP) for copper was synthesized for selective extraction of copper from different samples for analysis using flame atomic absorption spectrophotometry. In the synthesis of ion-imprinted polymer Cu(II) ion (template), 2,2'-bibyridine (ligand) and 4-vinylpyridine (functional monomer) which formed a complex through coordination with Cu(II) ion, ethylene glycol dimethacrylate (cross-linker) and 2,2'-azobisisobutyronitrile (initiator) were used. The ion-imprinted polymer and non-imprinted polymer (NIP) were synthesized via precipitation polymerization process. The synthesized polymers were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. Variables affecting the solid phase extraction of Cu(II) such as pH, initial Cu(II) concentration and time were studied in batch experiments. Quantitative retention of Cu(II) on IIP was achieved at pH 7. The IIP selectivity for copper ion extraction was higher as compared to NIP in the presence of other competing metal ions. The method was successfully applied to the determination of copper in multivitamin tablet, various natural water samples and industrial effluent.

Extraction of Copper from Sulfate Solutions with Hydrazides of Versatic Higher Acids in the Presence of Accompanying Metals

Fundamental aspects of the extractive recovery of copper(II) in the presence of accompanying metals from sulfuric acid solutions with hydrazides of Versatic (GVIK 509) α-branched tertiary carboxylic acids in kerosene or its mixture with modifying agents: 2-ethylhexanol or alkylphenol. The selective extraction of copper(II) in the presence of nickel(II), cobalt(II), zinc(II), and iron(III) with hydrazides in kerosene is possible at pH 0.1–0.6. The separation coefficients of element pairs were calculated. It was found that the modifiers have no effect on the quantitative extraction of copper(II), but strongly change the extraction pattern of the metals under study. It was shown that the re-extraction of copper(II) with sulfuric acid solutions is in principle possible.

Selective copper extraction from sulfate media with N,N-dihexyl-N′-hydroxypyridine-carboximidamides as extractants

Abstract Solvent extraction studies of copper(II) from sulfate media have been carried out using a selected non-commercial extractant N,N-dihexyl-N′-hydroxypyridine-2-carboximidamide (DH2PIA) diluted with toluene and heptane. The presented results indicated that the extraction of copper(II) was very sensitive to the pHeq, extractant concentration and the type of diluent. Also the pH0.5 values depended on the type of diluent and varied from 2 for heptane to 2.8 for toluene. The isotherms of the extraction and the McCabe-Thiele diagram revealed that using the single stage extraction at O/A = 2 Cu(II) can be removed almost completely from the leach solution. Stripping of the loaded copper(II) to the sulfuric acid solution (10%, A/O = 10) yielded rich electrolyte with 37.7 g/L Cu(II), while the stripping test with the spent electrolyte allowed for enrichment of the solution to 67.6 g/L Cu(II). Moreover, the extraction of Cu(II) with DH2PIA from a leach solution containing also Fe(II) is selective and allows to enrich the organic phase in Cu(II).

Selective precipitation of Cu in manganese-copper chloride leaching liquor

Recovery of valuable metal from industrial waste is critically important for wastewater treatment and recycling. In the present work, we developed a new method for selective copper extraction from the actual industrial manganese-copper chloride leaching liquor, which was produced in wet extraction of cobalt. The theoretical pH value for selective copper precipitation was calculated, which was in the range of 2.80–4.71. Manganese carbonate was used for selective copper deposition, and the factors that could affect the precipitation performance were investigated. The procedure for selective precipitation of copper was optimized as follows: the amount of manganese carbonate was twice the theoretical amount of neutralization acid; the reaction temperature and time were 60°C and 4.0h, respectively. Under the optimal conditions, the copper deposition rate was higher than 90%, while the deposition rates of other ions were lower than 10%. The XRD and SEM results showed that the copper-rich precipitate was granular and its main component was Cu2(OH)3Cl.

Development of an Electrolytic Process for Selective Extraction of Copper from Chemical and Biological Leachates from Electronic Waste

Development of an Electrolytic Process for Selective Extraction of Copper from Chemical and Biological Leachates from Electronic Waste