Copper Leaching Research Articles

Comparison of Leaching of Copper–Nickel Concentrates and Metallurgical Slag with Biogenic Ferric Iron

Comparison of Leaching of Copper–Nickel Concentrates and Metallurgical Slag with Biogenic Ferric Iron

Metal leaching test of commercially available faucets in the Japanese market in 2016-2020.

In this study, metal leaching was investigated in commercially available faucets in Japan to clarify their compliance to Japanese regulations. We purchased 37 faucets from the market and analyzed the leaching of cadmium, mercury, selenium, lead (Pb), arsenic, hexavalent chromium, boron, zinc (Zn), copper, manganese, and nickel. The leaching tests were performed with and without a conditioning treatment, that simulated approximately 1-month intermittent use of faucets on weekdays, and the results were compared to estimate the changes in metal leaching during the use of faucets. The results revealed that metal leaching from most of the faucets complied with Japanese regulations. However, the levels of Pb leaching from several faucets produced by certain manufacturers exceeded the Japanese standard. The conditioning treatment was generally effective in reducing metal leaching. However, the reductions in Pb and Zn leaching tended to be lower than those of the other metals. Nickel is not legally regulated in Japan; although the number of cases where nickel concentration in leachate exceeded the water quality management target value was greater, such cases were limited to faucets primarily made of copper alloys. We believe that these results will be helpful to improve the public health associated with metal leaching from faucets.

Efficient electrocatalytic nitrate reduction via boosting oxygen vacancies of TiO2 nanotube array by highly dispersed trace Cu doping

Nitrate pollution of water bodies is a serious global-scale environmental problem. The electrocatalytic nitrate reduction reaction (NO3RR) using Cu-based electrodes allows excellent nitrate removal; however, its long-term operation results in copper leaching, leading to health risks. This study proposes a strategy for efficient nitrate removal through the activation of oxygen vacancies on a highly dispersed Cu-doped TiO2 nanotube array (Cu/TNTA) cathode via electrodeposition. The mechanism underlying the activation of oxygen vacancies and enhancement in charge transfer at the cathode–pollutant interface upon trace (0.02 wt%) Cu doping is elucidated by electron paramagnetic resonance analysis, UV–visible diffuse reflection spectroscopy, and Raman spectroscopy. The Cu/TNTA-300 exhibits a nitrate removal rate of 84.3% at 12 h; the electrode activity did not decrease after 10 cycles, and no Cu2+ was detected in the solution. Electrochemical characterization and density functional theory calculations demonstrate that Cu doping promotes efficient charge transfer between nitrate and the electrode and reduces the energy barrier of the nitrate reduction reaction. This work provides a platform for novel design of cathodes for use in efficient and safe electrocatalytic nitrate reduction in environmental water bodies.

Facile preparation of anti-biofouling reverse osmosis membrane embedded with polydopamine-nano copper functionality: Performance and mechanism

In this study, we conducted a facile membrane modification process by mild electroless deposition of copper nanoparticles (CuNPs) integrating polydopamine (PDA) coating to combat biofouling of thin-film composite (TFC) reverse osmosis (RO) membranes. Various experimental tests and characterization techniques have been applied to reveal the anti-biofouling performance and underlying mechanism of prepared membranes (i.e., Cu/PDA/TFC membrane). The successful functionalization with PDA and CuNPs highly enhanced the anti-fouling properties of Cu/PDA/TFC membrane, as evidenced by 45%, 40% and 37% respectively lower adsorption of bovine serum albumin, humic acid, and lipopolysaccharide in static adhesion assays. A significant decreased membrane-foulant adhesion forces by 63% was observed for Cu/PDA/TFC membrane compared to control membrane, which is ascribed to enhanced membrane surface hydrophilicity after PDA coating. Moreover, The Cu/PDA/TFC membranes presented significantly decreased cell viability (E. coli from 90% to 22%, P. aeruginosa from 89% to 26%, and S. aureus from 84% to 18%), and reduced adenosine tri-phosphate (ATP) content after 3 h bacterial exposure (E. coli by 57%, P. aeruginosa by 50%, and S. aureus by 56%). Assessment on cell viability and metabolic activities of bacteria deposited on membrane indicate that contact-mediated toxicity contributed to the antibacterial mechanism of Cu/PDA//TFC membrane. In addition, the reduced viability of the planktonic cells at the membrane surroundings under durable copper leaching (∼17 mg/m2 to ∼9 mg/m2) suggest that release of antibacterial Cu2+ ions also played an important role in membrane antibacterial mechanism. Both contact-mediated and Cu2+ release-based antibacterial mechanisms endow Cu/PDA/TFC membrane with excellent anti-biofouling capacity under long-term dynamic condition, with 45% lower flux decline compared to the control membrane.

Electrooxidation of Alcohols on Mixed Copper–Cobalt Hydroxycarbonates in Alkaline Solution

AbstractMixed Cu‐Co hydroxycarbonates of the type (Cu1–xCox)2CO3(OH)2 have been synthesized over the whole range of Cu‐Co substitution (0≤x≤1) by co‐precipitation and their electrocatalytic activity in the oxidation reactions of ethanol (EOR), ethylene glycol (EGOR) and glycerol (GOR) in alkaline environment was evaluated to retrieve composition–activity correlations. Generally, cobalt incorporation led to higher activities for the alcohol oxidation (AOR) compared to the Cu‐only material and the results are compared with the competing oxygen evolution reaction (OER). On the Cu‐Co hydroxycarbonates, the electrooxidation of vicinal alcohols such as glycerol and ethylene glycol requires lower overpotentials than EOR and OER. Cu leaching from the hydroxycarbonate structure was observed in the presence of vicinal alcohols. The impact of chemical and electrochemical leaching of copper from the catalysts has been studied. The chemically leached catalyst was found to show increased AOR activity compared to other hydroxycarbonates, enabling the formation of larger amounts of formic acid during GOR measured in a circular flow cell electrolyzer. The results highlight that Cu‐Co hydroxycarbonates can be used as precursors to generate electrocatalytically active materials from Cu‐Co hydroxycarbonates for the AOR in alkaline solution.

Heterogeneous Fenton degradation of persistent organic pollutants using natural chalcopyrite: effect of water matrix and catalytic mechanism.

Natural chalcopyrite was evaluated as heterogeneous Fenton catalyst. Catalytic performance was evaluated considering different systems, catalyst dosage, H2O2 concentration, and reaction temperature, and increasing the parameters favors rhodamine B degradation. Effect of aqueous matrix was systematically examined, involving solution pH, anions, cations, dissolved organic matter, and initial pollutant concentration. The degradation performance is slightly influenced by these parameters. Rhodamine B removal is 96.5% within 120min, the rate constant ranges from 0.0086min-1 to 0.0415min-1 depending on temperature, and the activation energy is 79kJ/mol. Effective degradation of different persistent organic pollutants including methylene blue, malachite green, sodium butyl xanthate, tetracycline, and p-nitrophenol is verified by UV-vis spectra. Natural chalcopyrite was characterized by advanced techniques including scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Reactions between chalcopyrite and H2O2 cause copper leaching and iron oxidation. Quenching experiments and electron paramagnetic resonance reveal the dominant role of hydroxyl radical in catalytic process. The catalytic mechanism induced by surface iron and leached copper derived from chalcopyrite is proposed.

Perspectives of Using DES-Based Systems for Solid–Liquid and Liquid–Liquid Extraction of Metals from E-Waste

In recent years, the linear economic model and global warming have shown that it is necessary to move toward a circular economic model. In this scenario, the recycling of waste electrical and electronic equipment (WEEE) with green processes is one of the pending tasks; thus, in the present review, advances in the solid–liquid and liquid–liquid extraction processes, processes among the most important for the recovery of metals from ores or WEEE, with green solvents such as deep eutectic solvents (DES) are presented and analyzed, identifying the present and future challenges. To date, most articles focused on one of the processes, be it solid–liquid or liquid–liquid extraction, while few reports included the entire hydrometallurgical process, which could be due to heterogeneity of the WEEE, a characteristic that influences determining the leaching kinetic and the leaching mechanisms. A deeper understanding of the phenomenon would help improve this process and the next stage of liquid–liquid extraction. This also leads to the fact that, at the liquid–liquid extraction stage, most articles considered synthetic pregnant leach solutions to evaluate each of the variables, whereas the stripping of the ions and the recycling of the DESs in continuous processes is a challenge that should be addressed in future work. From the analysis, for WEEE leaching, it was identified that acid DESs are those achieving the best extraction percentages in the leaching of copper, lithium, and cobalt, among others, where the most studied hydrogen bond acceptor (HBA) is choline chloride with an acid (e.g., citric or lactic acid) as the hydrogen bond donor (HBD). For the liquid–liquid extraction of ions is a greater variety of HBAs (e.g., lidocaine, trioctylphosphine oxide and triphenyl phosphate) and HBDs (e.g., decanoic acid, thenoyltrifluoroacetone, and benzoyltrifluoroacetone) used; however, studies on the extraction of cobalt, lithium, copper, and nickel stand out, where the pH and temperature parameters have great influence.

Sedimentology, Metallographic Characteristics and Geodynamic Evolution of the Merija Copper Deposit (Marginal Folds Basin, Eastern High Atlas, Morocco)

The Merija copper deposit is located in the Marginal Folds of the Moroccan Eastern High Atlas. It is a stratiform deposit hosted in sandstone-conglomerate formations of the Infra-Cenomanian, consisting of copper carbonate and sulphide mineralization (malachite, azurite, traces of chalcopyrite, chalcocite, and covellite). This mineralization exhibits different forms: dissemination in the sandstone-conglomerate host rocks and fillings of centimetric veins, sometimes with calcite. Moreover, microscopic examination shows that the mineralization is disseminated in the carbonate matrix, filling of the inter-granular spaces of the sandstone-conglomeratic material. The mineralogical association is composed of: a primary paragenesis with chalcopyrite ، a secondary cementation paragenesis with chalcocite and covellite and a secondary oxidation paragenesis with malachite. This latter is the most dominant mineral presenting a micro-fibrous texture surrounding the sulphides of the primary and secondary paragenesis, composed of chalcopyrite, chalcocite and covelite. It is associated with a quartz-calcite gangue. The copper mineralization at Merija is heterogeneously distributed within the surrounding sandstone-conglomerate formation due to the diversity of paleocurrents carrying the leached copper. The rich paleocurrents trends S, SW, and SE, whereas the poor ones present an N and NW directions. These paleocurrents are derived from a fluvio-deltaic channel system that controlled sedimentary deposition in the area during the Infra-Cenomanian. This sedimentary type mineralization is probably related to a process of alteration and deposition of detrital materials loaded with copper minerals and derived from a protore copper-bearing. This alteration process gave rise to the malachite and azurite mineralization resulting from the replacement phenomenon of chalcopyrite, chalcocite and covellite.

Synthesis design of Cu/Al2O3 catalysts to decrease copper leaching in the catalytic wet peroxide oxidation of phenol

This work aims to study the catalytic performance of Cu/Al2O3 catalysts in the catalytic reaction of oxidation of phenol. The addition of La and Mn to Al2O3 support and the calcination temperature influence on the catalytic performance and Cu leaching were studied. The addition of either La or Mn to the support triggered less Cu leaching compared to the unmodified support. The catalysts modified with Mn and calcined at 650ºC and 900 °C yielded low Cu leaching values and high phenol conversions at 120 min of reaction, achieving total consumption of H2O2. The catalysts prepared in the same way but modified with La and calcined at 900 °C, achieved 100% phenol conversion and higher TOC conversion. Copper leaching was higher when the support was modified with La, but improved when compared to the unmodified support, suggesting that the presence of Mn allowed a better anchoring of Cu on the support. However, this was not beneficial for the reaction since a certain amount of Cu in the homogeneous phase was required for the reaction to start. Cu-La-Al2O3 showed stability after consecutive reaction cycles with the corresponding calcinations in each cycle.

Ultrafiltration Membranes Functionalized with Copper Oxide and Zwitterions for Fouling Resistance.

Polymeric membrane fouling is a long-standing challenge for water filtration. Metal/metal oxide nanoparticle functionalization of the membrane surface can impart anti-fouling properties through the reactivity of the metal species and the generation of radical species. Copper oxide nanoparticles (CuO NPs) are effective at reducing organic fouling when used in conjunction with hydrogen peroxide, but leaching of copper ions from the membrane has been observed, which can hinder the longevity of the CuO NP activity at the membrane surface. Zwitterions can reduce organic fouling and stabilize NP attachment, suggesting a potential opportunity to combine the two functionalizations. Here, we coated polyethersulfone (PES) ultrafiltration membranes with polydopamine (PDA) and attached the zwitterionic compound, thiolated 2-methacryloyloxyethyl phosphorylcholine (MPC-SH), and CuO NPs. Functionalized membranes resulted in a higher flux recovery ratio (0.694) than the unfunctionalized PES control (0.599). Copper retention was high (>96%) for functionalized membranes. The results indicate that CuO NPs and MPC-SH can reduce organic fouling with only limited copper leaching.

Cu- and Fe-substituted ZSM-5 zeolite as an effective catalyst for wet peroxide oxidation of Rhodamine 6 G dye

Several Cu-exchanged and Fe-exchanged ZSM-5 catalysts were prepared and studied for the decoloration, degradation and mineralization of Rhodamine 6 G in catalytic wet peroxide oxidation (CWPO). The Cu-ZSM-5 catalysts were shown to be more effective than the parent H-ZSM-5 zeolites (containing Fe-ions as impurity) and Fe-exchanged ZSM-5 to Rhodamine 6 G oxidation by hydrogen peroxide. Effects of copper loadings, Si/Al ratio, structure of copper species, and initial pH were ascertained on catalytic behavior of Cu-ZSM-5 and copper leaching under CWPO conditions. At acid pH, the highest decoloration of Rhodamine 6 G was typical of Cu-ZSM-5 with Si/Al equal to 30 and Cu content of ca. 0.5 – 0.65 wt% having isolated Cu2+ ions, whereas the maximal conversions of total organic carbon (TOC) were exhibited by catalysts with 1.5 – 2.8 wt% Cu and CuO-like clusters on the external zeolite surface. At alkali pH, the over-exchanged 2.8% Cu-ZSM-5 with CuO-like clusters was more active than under-exchanged 0.5% Cu-ZSM-5 to decoloration of Rhodimine 6 G, while both catalysts provided identical TOC conversions. Catalyst with 0.5 wt% copper loading showed reproducible activity up to 7th cycle. According to UV-Vis DR and EPR studies, the high efficiency of Cu-ZSM-5 to Rhodamine 6 G oxidation in acid solution is provided by the isolated Cu2+ ions, while the nanostructured square-planar CuO-like clusters (on the zeolite surface) ensure activity at alkali pH. Two mechanisms of organic substrate oxidation, i.e. radical (Fenton-like) mechanism activated by isolated Cu2+ ions and nucleophilic substitution via copper-hydroperoxide complex generation, were discussed.

Prediction of lead leaching from galvanic corrosion of lead-containing components in copper pipe drinking water supply systems

Galvanic corrosion is one of the main reasons for pipe degradation and lead contamination in drinking water systems. The electrical connection of dissimilar metals in corrosive tap water accelerates the dissolution rate of lead from leaded materials. This paper reports an electrochemistry based model to predict lead leaching from a copper pipe fitted with leaded connections. The corrosion of lead at the metal-electrolyte interface depends on the charge transfer and the electric field across the interface. The electric potential field and the mass transport process are dynamically coupled for corrosion propagation in stagnant water; they are respectively governed by the conservation of charge and reactant mass. Using polarization parameters for the electrodes as a function of concentration of oxidizing agents, a dynamic electrochemical model is developed to predict lead leaching from galvanic corrosion. The predicted lead and copper leaching curves are in good agreement with the experimental data for a lead-soldered coupled copper pipe, a brass valve coupled copper pipe, and a pure copper pipe. The findings offer a quantitative understanding on galvanic corrosion in drinking water supply systems and a practical modeling framework for prediction of lead leaching in tap water as a function of stagnation time.

Biomass-derived activated carbon as catalyst in the leaching of metals from a copper sulfide concentrate

Chalcopyrite is the resource with the highest amount of Cu content representing around 70–80% of the known reserves in the world. However, chalcopyrite like other copper sulfides, is usually found in deposits with grades around 0.4–0.5% copper. The exploitation of these reserves using traditional flotation methods followed by pyrometallurgical treatment of copper concentrate is at the limit of economic viability. Hydrometallurgical route would be more suitable for treating of these low-graded sulfide ores. However, chalcopyrite is refractory in ferric/sulfuric acid media and shows slow dissolution rates. For this a number of researches were carried out to accelerate the kinetics of leaching by adding pyrite, iron powder, nanosized silica, coal and activated carbon. The main objective of the present work was to study the use of one biomass-derived activated carbon as catalysts in the leaching of copper from chalcopyrite. Sulfuric acid solution of pH 1 with 5 g L−1 of Fe3+ was used as leaching agent. Experiments were performed at 90 °C and 250 rpm, during 48 and 96 h. Concentration of Cu, Zn, As, Sb and Co in the liquid phase was determined in order to evaluate their extraction degree, whereas solid residues were characterized by SEM-EDS and XRD. The presence of biomass-derived activated carbon significantly increased the extraction of copper, decreasing the leaching of arsenic. Furthermore, the use of biomass-derived activated carbon led to lower amounts of crystalline sulfur in the final residue.

Simulation of Simultaneous Leaching of Copper and Cobalt Minerals in Acid-Reductive Media: Sensitivity Analysis and Optimization

Simulation of Simultaneous Leaching of Copper and Cobalt Minerals in Acid-Reductive Media: Sensitivity Analysis and Optimization

Effect of copper/nickel ratio on the efficiency of biobeneficiation of bulk copper-nickel sulfide concentrates

The dependence of the efficiency of biobeneficiation (via bioleaching) of bulk copper-nickel sulfide concentrates on the ratio of copper to nickel sulfide minerals was studied. The copper content in the concentrates ranged from 10.8 to 19.1% (copper occurred in chalcopyrite), while the content of nickel was within 4.6–9.5% (nickel occurred in pentlandite and violarite). Although the copper content was higher than the content of nickel in all concentrates, the rate of nickel leaching significantly exceeded that of copper leaching. For the concentrates characterized by copper/nickel ratio (k) equal to 1.15 and 1.5, the average nickel leaching rate was ˃8 times higher than the copper leaching rate. Bioleaching of all studied concentrates allowed the obtainment of copper concentrates in solids (copper content of 15.6–18.7%) in which nickel content was low (0.27–1.49%). The high level of nickel dissolution and the maximum increase in the copper content in the solids were shown for the concentrate with the initial copper and nickel content of 10.9 and 7.2%, respectively (k of 1.5). In this bioleach residue, the copper content increased by 4.7%, while the nickel content decreased by 6.86% compared to the original concentrate. Thus, bioleaching of copper-nickel concentrates can be considered biobeneficiation, and the highest efficacy of the process may be achieved at a copper/nickel ratio of ∼1.5.

Recovery of metallic copper from waste printed circuit boards via H3NO3S-NaCl-H2O2 leaching system

In this study, sulfamic acid (H3NO3S) was used to leach Cu from waste printed circuit boards (WPCBs) by using hydrogen peroxide as strong oxidant and NaCl as additive. The effects of NaCl concentration, sulfamic acid concentration, hydrogen peroxide concentration, temperature and reaction time on copper leaching were investigated. Under the optimum operated conditions, the leaching rate of copper was 91.24%. The thermodynamic analysis predicted that the dissolution of copper was promoted by adding NaCl to the mixed leaching solution of H3NO3S and H2O2. Kinetic analysis shows that the leaching process was controlled by solid film diffusion with an apparent activation energy of 7.78 kJ/mol. Through the analysis of zoom stereo microscope and X-ray diffraction (XRD), copper failed to completely leach because it was wrapped by insoluble substances, which prevented further leaching of copper. The leaching of copper from WPCBs with H3NO3S-NaCl-H2O2 system was an efficient and environmentally friendly method. Based on this study, a new process for recovering WPCBs is proposed.

A study to understand the role of ethylene glycol in the oxidative acid dissolution of chalcopyrite

Recent investigations suggest that ethylene glycol (EG) performs two important functions in the oxidative dissolution of chalcopyrite with hydrogen peroxide: it prevents H2O2 dismutation on the chalcopyrite surface and, secondly, it hinders H2O2 decomposition due to the presence of dissolved copper and iron in the leach liquor. Of these two, retarding the H2O2 breakdown probably contributes most to the observed improvement in copper leaching; however, the nature of the role that EG plays in the solution is unclear. For that reason, a systematic study was undertaken, at different concentrations of sulfuric acid and EG, to reveal the role of EG in the leaching process. The results of this investigation show that EG hinders H2O2 degradation by decreasing the copper and iron activities in the solution through Cu (II)-EG and Fe (II, III)-EG complex formation. Likewise, the slowing effect strongly depends on the H2SO4 concentration because the Fenton reaction, which is responsible for the decomposition, increases its efficiency with lower acid concentrations (<0.1 M). Thus, successful leaching could be attained with concentrations above 0.7 M and 0.1 M of sulfuric acid and EG, respectively; otherwise, rapid H2O2 degradation and simultaneous EG mineralization (complete oxidation, in other words, oxidation to CO2 and H2O) are favored as a consequence of the reactions between H2O2 and the leached metals and the OH* radicals produced in the leach liquor, respectively. In view of these results, a brief discussion is presented on the implications of chalcopyrite leaching with H2O2, showing alternatives to increase its performance.

Optimization of process parameters and kinetic modelling for leaching of copper from oxidized copper ore in nitric acid solutions

The leaching behavior of Tunceli malachite mineral was investigated in nitric acid solutions by two steps to evaluate the effect of various experimental parameters. In the first step, the optimal conditions for the leaching process were determined, while in the second step, a kinetic evaluation for the process was performed. In the optimization experiments, the concentration of nitric acid, temperature, stirring speed, and solid-to-liquid ratio were selected as the independent variables, and the central composite design method (CCD) was applied to the experimental data. At the end of the experiments, the optimal values for the concentration of nitric acid, temperature, solid-to-liquid ratio and stirring speed were determined to be 0.5 mol/L, 50 °C, 0.004 g/mL and 500 r/min, respectively. Under the optimal conditions, the leaching rate was found to be 99% for 120 min of reaction time. In the kinetic evaluation tests, the effects of the concentration of nitric acid, temperature, stirring speed, solid-to-liquid ratio and particle size on the leaching rate of copper from malachite were investigated. In these tests, it was determined that the leaching rate increased with the increase in the temperature, acid concentration and stirring speed, and with the decrease in the particle size and solid-to-liquid ratio. In consequence of the kinetic analysis, it was observed that the leaching kinetics followed the mixed kinetic model, and a mathematical model for the leaching process was introduced. The activation energy for this process was calculated to be 36.23 kJ/mol.

Leaching of Copper Contained in Waste Printed Circuit Boards, Using the Thiosulfate-Oxygen System: A Kinetic Approach.

The present work is related to the treatment of crushed waste of printed circuit boards (WPCBs) from electrical and electronic devices (WEEE), carrying out the recovery of copper in solution. In the first stage, the studied material was characterized by AAS, SEM-EDS, and XRD. The results revealed significantly high amounts of copper (744.42 mg/g), compared with the rest of the metals present in the sample, mainly iron and zinc. In the second stage of the work, alkali dynamic leaching experiments were carried out in the medium, evaluating important kinetic variables in order to verify the controlling step of the system and adjust the data to a kinetic model. According to the results obtained from the various experimental tests executed, it was found that in the studied system of , the leaching of copper was preferably adjusted to the model of spherical particles with a shrinking core finding a mixed chemical–diffusive control, with values of Ea = 25.78 kJ/mol and n = 0.22 (for the leaching reagent), indicating that the reaction was controlled by the oxygen transport to the solid–liquid interface and also by the chemical reaction in the surface of particles, obtaining up to 99.82% copper in solution.

Catalysing electrowinning of copper from E-waste: A critical review

Smart technologies and digitalisation have increased the consumption of scarce metals that threaten the sustainability of intricated industries. Additionally, the growing streams of waste electrical and electronic equipment (e-waste) are significant hazards to public health and the environment. Thus, there is an escalating need to recover metals from e-waste for sustainable management of metal resources. Hydrometallurgical processing of e-waste, involving copper (Cu) leaching and its subsequent recovery from pregnant leach solution (PLS) via electrowinning, has emerged as an efficient strategy to close the recycling loop. Electrowinning from PLS demonstrated higher Cu recovery efficiency and operational feasibility with a lower reagent use and lesser waste generation. Nevertheless, multiple issues challenged its practical implementation, including selective recovery of Cu from PLS containing mixed metals and high energy consumption. This review (1) identifies the factors affecting Cu electrowinning from PLS; (2) evaluates the composition of lixiviants influencing Cu electrowinning; (3) appraises various catalysts developed for enhancing Cu electrodeposition; and (4) reviews coupled systems that minimised process energy consumption. From the literature review, electrocatalysts are prospective candidates for improving Cu electrowinning as they reduced the cathodic reduction overpotentials, enhanced surface reaction kinetics and increased current efficiency. Other catalysts, including bioelectrocatalysts and photoelectrocatalysts, are applicable for dilute electrolytes with further investigations required to validate their feasibility. The coupled systems, including slurry electrolysis, bioelectrochemical systems and coupled redox fuel cells, minimise process energy requirements by systematically coupling the cathodic reduction reaction with suitable anodic oxidation reactions having thermodynamically low overpotentials. Among these systems, slurry electrolysis utilising a single-step processing of e-waste is feasible for commericalisation though operational challenges must be addressed to improve its sustainability. The other systems require further studies to improve their scalability. It provides an important direction for energy-efficient Cu electrowinning from PLS, ultimately promoting a circular economy for the scarce metal resources.