Solvent Extraction Of Copper Research Articles

Efficient ammoximation and regeneration of degraded hydroxyoxime CP150 over TS-1 molecular sieve/H2O2 system and reuse for solvent extraction of Cu(II)

The regeneration of failed hydroxyoxime extractants in the copper hydrometallurgy industry is crucial. However, the existing regeneration system has limitations in terms of operability, yield, and environmental friendliness, which restricts its industrial application. This paper presents a clean one-pot ammoximation regeneration system for the in-situ preparation of hydroxylamine for the oximation of aldehydes, catalyzed by TS-1 with NH3 and H2O2. It was tailored based on the characteristics of the degraded organic phase produced by long-term operation at the copper solvent extraction site. The developed system demonstrates an excellent regeneration conversion efficiency (>90%) for the degraded copper-extracted organic phase. Following regeneration, the copper extraction efficiency of the organic phase reaches the same level as the fresh organic phase and maintains good copper extraction stability even after multiple extraction cycles. Moreover, the phase separation performance was improved through optimization. This regeneration system meets the demand for environmentally friendly and resourceful utilization of degraded waste organic phases in copper extraction systems.

Obtention of Suitable Pregnant Leach Solution (PLS) for Copper Solvent Extraction Plants from Copper Concentrate Using Hydrogen Peroxide and Iodine in a Sulfuric Acid–Chloride Medium

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.

Extraction of Copper from Pregnant Leach Solution (PLS) and Reduction of Crud Formation

ABSTRACT Presented universal recommendations for the reduction of crud formation, reviewing various aspects affecting the loss of diluent and extractant due to the formation of a third phase (crud), encountered in many hydrometallurgical plants using copper solvent extraction. In this paper introduce the reasons of the crud formation , description of the stable emulsions containing solid particles and choice of technological scheme. An analysis of operations to be considered in the operation of copper solvent extraction plants is presented, due to the deterioration of copper grade below 0.5% in ore and the increase in aluminum content up to 20–25%. Results of use of extraction properties of modified extractants of ACCORGA series and unmodified extractant Lix984N on pregnant leached solution of the most important deposits (Almaly and Aktogay) are given. It is established that for solutions of Almaly deposit, ACCORGA5640 and unmodified Lix984 extractants have high selectivity to copper. Distribution of iron, silica, and copper ions during extraction was studied, and it was found that high selectivity to copper/iron and copper/silica is possessed by extractant Lix 984N, ACCORGA5640. It was found that for solutions of the Aktogay deposit, the ratio of interphase suspension in both extractants is the same, and phase separation in experiments with the use of extractant Lix 984N was 10 s shorter with the use of extractant ACCORGA5640. It was found that the addition of ACCORGACR60 reagent in the amount of 5-10 ppm also leads to a decrease in the volume of crud by 13%, for a stronger suppression of crud.

Process intensification of metal solvent extraction studies using a miniaturized solvent extraction plant

This study examines the potential of a miniaturized solvent extraction plant (MSXP) to improve the efficiency and reproducibility of laboratory and pilot-scale metallurgical studies that typically require extended testing periods. The MSXP has been designed to replace conventional solvent extraction (SX) apparatus and aims to reduce start-up time, time to reach equilibrium, and overall test time. Two copper solvent extraction (Cu-SX) research campaigns were conducted to test the functionality, ease of operation, modularity, and reproducibility of the MSXP. The first campaign quantified the extraction efficiency and net copper transfer, while the second campaign operated the MSXP in a semicontinuous countercurrent flow configuration with three extraction and two stripping stages. The main variables studied in the first campaign are the number of stages (1-3), volumetric flow rates (O/A, 1-3), and organic phase residence time in the micro-contactor (0.7-2.4 min). The results demonstrate that the MSXP can work with very low stage efficiencies (48%), while achieving high copper recoveries (> 90%). At the stripping circuit level, we show that the MSXP can operate at superior stage efficiencies (> 100%), with low copper recoveries (30%–55%). The reproducibility evaluation also demonstrates high statistical confidence (< 6% CV) in the obtained process values. The MSXP offers great flexibility in net copper transfer and can be used to benchmark and emulate a wide range of Cu-SX systems. Experimental Cu-SX campaigns can be run in about 60 min while investing roughly US$1.4/h on reagents, which is significantly lower compared to typical campaigns that can last from days to weeks to reach reliable research outcomes and require about US$62/h for reagents. The potential of MSXP extends to more elaborate solvent extraction systems, specifically those designed to purify energy-critical elements like lithium, nickel, cobalt, or rare-earth elements. This study demonstrates the promise of process intensification approaches for improving the efficiency of laboratory and pilot-scale SX studies, which can help in reducing time, reagents, and energy consumption while improving the reproducibility of results.

Copper solvent extraction on the African Copperbelt: From historic origins to world-leading status

Approximately 20% of current world copper cathode output is produced using a hydrometallurgical process route, generally referred to as the leach-solvent extraction-electrowinning flowsheet. Since its commercialization in the late 1960s, steady improvements in the performance and efficiency of the solvent-extraction reagents and equipment, combined with significant developments in leaching and electrowinning, have made an ever-widening range of ore types amenable to this technology. Following successful implementation on all major continents, a large proportion of growth in recent years derives from the re-emergence of copper solvent extraction in the Central African Copperbelt. This review provides a brief history of the development and evolution of copper solvent extractants and mixer-settler contactors, and the significance of the Copperbelt region in achieving commercialization and acceptance of the technology. The opportunities and challenges presented by the abundant high-grade oxide ores of the Copperbelt are contrasted with the processing of solutions derived from the low-grade mixed oxide-sulfide ore bodies that are prevalent in other geological regions. The current status of hydrometallurgical copper production in the African Copperbelt, within a global context, and a medium-term outlook for the technology are discussed.

Effect of synthesis routes on the microstructural properties of nano zero-valent metals of Fe and Cu synthesized from the industrial copper solvent extraction process

Nano zero-valent iron (NZVI) and nano zero-valent copper (NZVC) synthesizing from the present industrial solution could be attractive due to some advantages such as preparing advanced materials through cost-effective methods and solving their disposal problems. Moreover, the present microstructural investigation probed the influence of synthesis routes used on NZVI and NZVC properties. Accordingly, the microstructural properties of nano zero-valent metals (NZVMs) synthesized through the green and chemical methods were calculated by the Rietveld method. The obtained results verified that NZVI was synthesized with titrating NaBH4 and green tea extract by chemical and green techniques from the industrial raffinate solution. NZVC was prepared from the industrial Cu-enriched solution through green and chemical techniques by titrating ascorbic acid and NaBH4, respectively. XRD and Energy Dispersive Spectroscopy (EDS) proved that NZVMs were synthesized and fairly oxidized. Microstructural studies also revealed that the amorphization degree was increased from 62.2% and 2.7% in the green NZVI and NZVC to 89.8% and 86.81% in chemically synthesized NZVI and NZVC, respectively. Considering green NZVMs, the crystallite size and unit cell were reduced in chemically synthesized NZVMs. Also, the microstrain changed from 2.79E-4% and 3.2E-3% in the green NZVI and NZVC to 2.4E-2% and 6.2E-4% in chemically synthesized NZVI and NZVC, respectively. The findings of this study indicated that the chemically synthesized NZVMs had smaller particles, crystallite size, unit cells and a higher amorphization degree, in favor of reactivity promotion and oxidation progress.

Solvent Extraction of Copper and EDTA in Electroless Copper Plating Wastewater Using a Quaternary Ammonium Salt

To separate both copper and 2,2',2'',2'''-(ethane-1,2-diyldinitrilo)tetraacetic acid (EDTA) from the waste electroless copper plating solution by solvent extraction, the liquid–liquid equilibria of the copper-EDTA complex and unbound EDTA ion were experimentally measured. An organic solution of tri-n-octylmethylammonium chloride (TOMACl) was used as solvent. The kerosene solution of TOMACl could extract both copper-EDTA complexes and EDTA ions from the model wastewater. The fractional removal and distribution ratios of both the copper-EDTA complex and EDTA ions decreased as the pH increased. The valence number of the major copper-EDTA complex or EDTA ion in the aqueous phase increased with pH, and the number of TOMA+ cations required to chelate the complexes and ions increased. These complexes and ions had lower reactivity with TOMACl owing to steric hindrance. These effects caused lower removal of both copper and EDTA in a higher pH range, which is a typical condition of waste electroless copper solution.

English Testing of the optimum extragent for solvent-extraction of Almaly deposit copper

For the solvent extraction of copper from pregnant leach solutions, (PLS) a wide range of modern extractants is currently offered on the market, and its choice is a very important issue in the production of copper using the SX-EW (Solvent Extraction and Electrowinning) technology. The purpose of this work was to determine the optimal copper extractant for processing productive solutions of the Almaly deposit using the SX-EW. The studies were carried out with a productive solution obtained by leaching copper ores from the Almaly deposit of composition, g/dm3: 1) Cu– 0.262, Fe–17.97, SiO2–0.36. The results of copper extraction from model solutions showed that the maximum extraction of copper (94%) is observed when using the extractant 5% Acorga 5640, while the other extractants did not provide a high degree of extraction of 10% Lix984 - 93%; 10% Acorga 5640 - 91%; 10% Acorga 5910 and 10% Acorga 5747 - 85% each. According to the results of the retraction process, a high degree of copper extraction from the organic phase (90.2 and more) was ensured when using extractants of 5% Acorga 5640, 10% Lix984, and 10% Acorga 5640, the minimum - at 10% Acorga 5910 (88.2%). For the extraction of copper from the productive solution of the Almaly deposit 5% Acorga 5640 was chosen as the optimal extractant.

Incorporation of chloride ion in a copper solvent extraction process: A thermodynamic view

In this study, the impact of chloride content of the seawater on the solvent extraction equilibrium of copper using LIX 984 N was investigated. This effect was studied considering the nonideality of aqueous and organic phases. The presence of chloride ion was shown to increase the extraction tendency toward copper extraction, considering the changes that occur in the ratio of the activity of the dominant copper species to the hydrogen ion (H+). This phenomenon was further confirmed by calculating the equilibrium constant of the copper solvent extraction reaction in presence and absence of the chloride ion. The occurrence of the chloride ion resulted in involvement and dimerization of more organic molecules in the transfer of copper to the organic phase. As a result, a heterogeneous model incorporating the nonideality of the organic and aqueous phases for the solvent extraction of copper was developed and validated by experimental data.

Endothermic solvent extraction of copper (II) with furfuryl thioalcohol from sulfate medium

A simple solvent extraction method was developed to extract copper (II) from sulfate solution. The extraction of copper (II) with furfuryl thioalcohol was investigated. The effect of variables such as aqueous phase pH, furfuryl thioalcohol concentration, temperature, stripping reagents, and diluents was investigated. The extraction data revealed that using 15% (v/v) furfuryl thioalcohol with aqueous solution containing 0.5 mol L-1 Na2SO4, equilibrium pH 5.5, and phase ratio organic phase: aqueous phase (O:A) of 1:1 resulted in 98.20 percent extraction of copper (II) without nickel coextraction (II). Extraction isotherm results show that the extraction procedure is endothermic, with ΔH = 28.542 kJ mol-1 and ΔS = 41.740 J K-1 mol-1. Using 2.0 M H2SO4, copper loaded in organic phase was stripped at a rate greater than 99 percent.

Solvent Extraction of Metal Ions from Synthetic Copper Leaching Solution Using R4NCy

Recent works suggest that the use of ionic liquids in the copper solvent extraction industry is feasible. However, the reports did not use real solutions (or synthetic solutions with various elements). This fact remains poorly established, and the interaction efficiencies are still under study. The objective of this research is to explore the extraction and stripping of the four major elements present in a copper industrial pregnant leach solution (Cu(II), Fe(III), Mn(II), and Zn(II)) using the methyltrioctyl/decylammonium bis(2,4,4-trimethylpentyl)phosphinate (R4NCy) ionic liquid as an extractant. The work conditions studied in extraction were ionic liquid concentration, initial pH, and O/A ratio, and in stripping were H2SO4 concentration and O/A ratio. The test was carried out at room temperature and ambient pressure. High efficiency and selectivity (99.82% and 113,755 over Cu(II), respectively) were observed for Fe(III) extraction over the other elements. Moreover, after the extraction test, significant difficulty in stripping Fe(III) loaded in the ionic liquid was observed (28.7% at 0.5 M of H2SO4). Finally, the present study demonstrates that the R4NCy ionic liquid is not suitable for copper extraction because it has a higher selectivity for Fe(III) and Zn(II).

Solvent extraction of copper(II) from sulfate media using neutral extractants, Cyanex-921 and Cyanex-923

Solvent extraction of copper(H) from sulfate media using neutral phosphine oxide extractants Cyanex-921 and Cyanex-923 in toluene has been performed. The extraction of Cu I I is quantitative in 0.8 and 0.1 M CH 3 COONa with 0.025 M Cyanex-921 and 0.25 M Cyanex-923 in toluene, respectively. The extracted Cu I I from the organic phases of both the extractants is stripped out with 4.0 M CH 3 COOH and determined spectrophotometrically. Effects of various parameters, such as sodium acetate concentration, reagent concentration, effect of various diluents and diverse ions on the extraction of copper are also studied. The extraction reactions proceed by solvation and their probable extracted species are [Cu(Ac) 2 .2(Cyanex-921)] and [Cu(Ac) 2 .2(Cyanex-921)].

Effect of Synthesis Routes on Microstructural Properties of Nano Zero-Valent Metals of Fe and Cu Synthesized from the Industrial Copper Solvent Extraction Process

Effect of Synthesis Routes on Microstructural Properties of Nano Zero-Valent Metals of Fe and Cu Synthesized from the Industrial Copper Solvent Extraction Process

An improved control strategy for an industrial copper solvent extraction process

ABSTRACT In this paper, to solve the constraints and upgrade the control systems of industrial copper solvent extraction processes, an improved two-layer (optimization and stabilization) control strategy was proposed. The proposed control strategy is equipped with an advanced–step multistage nonlinear model predictive controller. It was successfully tested against simulated disturbances, noise and set point changes. Moreover, the proposed strategy was applied for an industrial process and the obtained results were compared to the plant control strategy and the latest proposed control strategy for industrial copper solvent extraction in the literature. With the proposed control strategy and the latest proposed control strategy in the literature, the production of the copper solvent extraction process was increased by almost 6% and 3%, respectively, compared to the plant control strategy, and the process variation was decreased by 90–92% and 80–85%, respectively.

Extraction of Cu(II), Fe(III), Zn(II), and Mn(II) from Aqueous Solutions with Ionic Liquid R4NCy

The leaching of copper ores produces a rich solution with metal interferences. In this context, Fe(III), Zn(II), and Mn(II) are three metals contained in industrial copper-rich solutions in high quantities and eventually can be co-extracted with the copper. The purpose of the current study was to determine the feasibly of solvent extraction with the use of ionic liquid methyltrioctyl/decylammonium bis (2,4,4-trimethylpentyl)phosphinate (R4NCy) as an extractant of Cu(II) in the presence of Fe(III), Zn(II), and Mn(II). In general terms, the results showed a high single extraction efficiency of all the metals under study. In the case of Fe(III) and Zn(II), the extraction was close to 100%. On the contrary, the stripping efficiency was poor to Fe(III) and discrete to Zn(II), but very high to Cu(II) and Mn(II). Finally, the findings of this study suggest that the ionic liquid R4NCy is feasible for the pre-treatment of the copper solvent extraction process to remove metal impurities such as Fe(III) and Zn(II).

Influence of Electrolyte Impurities from E-Waste Electrorefining on Copper Extraction Recovery

In order to reflect possible issues in future sole e-waste processing, an electrolyte of complex chemical composition reflecting system of sole e-waste processing was obtained by following a specially designed pyro-electrometallurgical method. The obtained non-standard electrolyte was further used for the purpose of comprehensive metal interference evaluation on the copper solvent extraction (SX) process. Optimization of the process included a variation of several process parameters, allowing determination of the effect of the most abundant and potentially the most influential impurities (Ni, Sn, Fe, and Zn) and 14 other trace elements. Moreover, comparing three commercial extractants of different active chelating groups, it was determined that branched aldoxime reagent is favorable for Cu extraction from the chemically complex system, as can be expected in future e-waste recycling. The results of this study showed that, under optimal conditions of 20 vol.% extractant concentration, feed pH 1.5, O/A ratio 3, and 10-min phase contact time, 88.1% of one stage Cu extraction was achieved. Co-extraction of the Fe, Zn, Ni, and Sn was under 8%, while Pb and trace elements were negligible. Optimal conditions (H2SO4 180 g/L, O/A = 2, and contact time 5 min) enabled 95.3% Cu stripping and under 6% of the most influential impurities. In addition, an impurity monitoring and distribution methodology enabled a better understanding and design of the process for the more efficient valorization of metals from e-waste.

Image analysis based mass transfer measurement in droplet breakage phenomenon

The effect of droplet breakage on mass transfer in copper solvent extraction was studied by measuring concentrations directly inside a droplet. Single organic phase droplet was rising through the aqueous copper sulphate solution. Organic phase consisted of hydroxyoxime type copper extractant dissolved into hydrocarbon diluent. The droplet collided with steel blade and was cut as it elongates and eventually breaks up. Droplet breakage was recorded on the video. Droplet sizes, velocities and concentrations were determined using image analysis of video frames. Results indicate that droplet breakup enhances mass transfer. Breakage and mass transfer times are short and mass transfer due to pure diffusion alone does not explain excess mass transfer. This is proposed to be due to extractant absorption on newly forming interface, which leads to increased extraction. Although measured droplet sizes are much larger than those formed in mixed tanks, the results provide insights for industrial copper extraction intensification.

Solvent extraction and kinetic studies of copper from a heap leach liquor using CuPRO MEX-3302

ABSTRACT The present study aims at assessing the potential application of CuPRO MEX-3302 in copper extraction from a heap leaching liquor. The role of influential significant parameters, including the leachate pH (0.1–2.7), CuPRO MEX-3302 concentration (5–15% (v/v)), temperature (25–70 °C), copper initial concentration (0.5 to 2.3 g/L) and extraction time (0–5 min), were investigated. The extraction efficiency at ambient temperature, 1:1 organic/aqueous phase ratio, 5% (v/v) extractant concentration, pH of about 2 and contact time of 30 min was found to be 95% with a value of Fe and Mn of less than 2%. Meanwhile, a two-step extraction process was dedicated on the basis of the McCabe-Thiele diagram to obtain an organic phase containing 2.9 g/L copper at pH of 2.1. Equilibrium analyses confirmed the association of 4 mol of CuPRO MEX-3302 per mole of extracted copper. The thermodynamic outcomes revealed a high affinity of the extractant together with an endothermic and spontaneous nature of copper extraction in the system studied. Moreover, the reaction kinetics showed that the reaction order of H+ and CuPRO MEX-3302 concentration was −0.54 and 0.50, respectively. Finally, a two-stage counter-current stripping simulation at Vo/Va = 1:1 with 180 g/L H2SO4 resulted in a copper stripping efficiency of 99.54%.

Solvent Extraction of Copper Enhanced by Mixing Cavities in Micromixer

Solvent Extraction of Copper Enhanced by Mixing Cavities in Micromixer

Biorremoción de iones de hierro de la solución de refinado de cobre utilizando “semilla” de jarosita biosintética promovida por Acidithiobacillus ferrooxidans

La disminución de la concentración de iones de hierro de una solución de refinado procedente de la extracción con solvente de cobre es importante para mantener una buena eficiencia de corriente en el proceso de electrolisis. En este estudio, se investigaron los efectos combinados de la “semilla” de jarosita biosintética y Acidithiobacillus ferrooxidans sobre la eliminación de hierro de la solución de refinado de cobre y el efecto del pH. La biosíntesis de “semillas” de jarosita de amonio se realizó de manera eficiente a pH 2 y una concentración de Fe2 + de 50 g·l-1. El porcentaje de eliminación de hierro de la solución de refinado a un pH de 1,5; 2,5 y 5% de dosis de semillas fue de 0,81%, 47,38% y 71,26%, respectivamente. La concentración de hierro en la solución de refinado disminuyó notablemente hasta alcanzar un valor del 71,17% con la incorporación de un 10% en peso de “semilla” de jarosita junto con un 10% V/V de A. ferrooxidans. Esto se debió al aumento en la superficie específica de los sólidos en la solución y a las características magnéticas de A. ferrooxidans que promueven la eliminación de hierro. Se seleccionó un pH 2 y una carga de “semillas” de jarosita del 10% como las condiciones óptimas para la eliminación del hierro de la solución de refinado. Se concluyó que se podría incrementar la recuperación de cobre del refinado biológicamente refinado.