An integrated production process from copper ore to electrolytic copper foil

Abstract

The application discloses an integrated production process from copper ore to electrolytic copper foil, which uses copper ore as a direct raw material, and realizes continuous manufacturing of copper ore to high-end electrolytic copper foil through crushing, coupling leaching of electrolysis backflow and crystallization mother liquor, iron powder replacement and impurity removal, solvent extraction enrichment, cooling crystallization, multi-stage electrolyte purification, electrolytic foil production and full-liquid flow closed loop circulation. The application omits high-energy-consumption intermediate links in the traditional process, such as cathode copper preparation, casting, upward continuous casting and copper wire copper dissolving, 100% of the crystallization mother liquor is returned to the leaching process, and the electrolytic foil backflow is purified and then circulated, the copper element recovery rate is greater than or equal to 99%, the electrolyte recycling rate is greater than or equal to 98%, the comprehensive production cost is reduced by more than 25%, and no production wastewater is discharged. The process can stably prepare 6-18 mu lithium battery copper foil and high-frequency high-speed copper foil, has the comprehensive advantages of high efficiency, low consumption, greenness, stability and high-end, and is suitable for large-scale industrial production.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metal smelting and electrolytic copper foil production technology, specifically relating to an integrated production process from copper ore to electrolytic copper foil. Background Technology

[0002] Electrolytic copper foil is a core material for strategic industries such as new energy, electronic information, aerospace, and automotive electronics. Lithium-ion battery copper foil directly determines the energy density, cycle life, rate performance, and safety characteristics of lithium-ion batteries, while high-frequency, high-speed copper foil is a key material for ensuring high-speed signal transmission, low loss, and high heat resistance. With the continuous increase in the penetration rate of new energy vehicles, the rapid expansion of the energy storage market, and the widespread adoption of 5G and artificial intelligence terminals, the demand for high-end electrolytic copper foil is maintaining an average annual growth rate of over 15%, placing extremely high demands on production process efficiency, energy consumption, environmental protection, product consistency, and cost control.

[0003] Traditional electrolytic copper foil production employs a long, segmented manufacturing process. The complete route is: copper ore → pyrometallurgical refining → electrolytic refining → cathode copper → smelting and casting → continuous casting → copper wire → air oxidation copper dissolution → electrolyte preparation → electrolytic green foil → post-processing → finished copper foil. This process suffers from systemic defects that are difficult to overcome: First, it is highly dependent on purchased cathode copper plates. The cathode copper requires two energy-intensive and high-emission processes: pyrometallurgical refining and electrolytic refining. Then, it undergoes smelting, casting, and continuous drawing to produce copper wire. The energy consumption of the smelting and casting stage alone accounts for more than 35% of the total energy consumption of the traditional process. Repeated high-temperature heating leads to coarse copper grains and impurity segregation, directly affecting the mechanical properties and surface quality of the copper foil. Second, the copper wire dissolution uses air bubbling oxidation, which has low mass transfer efficiency and a slow copper ion dissolution rate. The capacity of a single copper dissolution tank is limited, and the dissolution process releases a large amount of acidic droplets, requiring a complex waste gas scrubbing system, resulting in high operating costs. Third, the lengthy process leads to frequent material transfers and significant physical losses of copper, resulting in a total copper recovery rate of only 92%–95%. A large amount of copper is lost with leaching residue, filter residue, and neutralization wastewater, resulting in low resource utilization. Fourth, the traditional process has a low electrolyte circulation rate, and the electrolytic wastewater needs to be neutralized, precipitated, and filtered, generating a large amount of copper-containing hazardous waste and high-salt wastewater, leading to high environmental governance costs and pressure. Fifth, each process operates independently with uncoordinated parameters, making it difficult to stably match impurity control, copper ion concentration, acidity, and temperature. This results in large batch fluctuations in high-end copper foil, making it difficult to meet the stringent consistency requirements of lithium batteries and high-frequency, high-speed applications.

[0004] In existing technologies, some companies have attempted to use industrial-grade copper sulfate to directly dissolve and prepare electrolytes, reducing the copper dissolution step. However, they still rely on purchasing smelter-grade copper sulfate, failing to break free from dependence on traditional copper smelting products. Furthermore, the purity of copper sulfate fluctuates greatly, and the impurity content is uncontrollable, making it impossible to meet the ultra-high purity requirements of battery-grade and electronic-grade copper foil. The process of preparing copper sulfate by wet leaching of copper ore is limited to the production of chemical raw materials and is not deeply coupled with the electrolytic foil production process. The leaching solution has high acidity, many types of impurities, mismatched copper ion concentration, and lacks a circulation system, making it unsuitable for direct use in the foil production process. A few short-process copper foil production technologies have not achieved full circulation of mother liquor and return liquor, resulting in significant copper loss, high acid consumption, and large wastewater discharge. Moreover, they lack a multi-stage purification system for high-end copper foil, leading to substandard product purity, surface roughness, and conductivity.

[0005] In summary, the industry urgently needs an integrated process that breaks through the constraints of traditional processes, directly starting from copper ore and integrating leaching, impurity removal, enrichment, crystallization, electrolyte purification, electrolytic foil production, and a closed-loop circulation of the entire liquid flow. This would achieve efficient copper recovery, significantly reduced energy consumption, near-zero wastewater discharge, and stable production of electrolytic copper foil to meet high-end applications. This invention addresses these pain points by providing a novel integrated solution for both ore and foil production through a closed-loop material flow, precise parameter coordination, graded impurity removal, and tiered utilization of thermal energy, filling a technological gap in the industry. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of traditional electrolytic copper foil processes, such as long process flow, high energy consumption, low copper recovery rate, high environmental pressure, and poor stability of high-end products. It provides an integrated production process from copper ore to electrolytic copper foil, realizing the direct conversion of copper ore into high-end electrolytic copper foil, eliminating multiple intermediate processes, significantly reducing energy consumption and costs, improving copper recovery rate and product consistency, and meeting the needs of large-scale production of lithium battery copper foil and high-frequency and high-speed copper foil.

[0007] This invention provides an integrated production process from copper ore to electrolytic copper foil, comprising the following steps: (1) Copper ore crushing and leaching: The copper ore is crushed to below 200 mesh and leached with a mixed electrolyte of electrolytic copper foil return liquid and crystallization mother liquor. The sulfuric acid concentration is controlled at 100-110 g / L and the temperature is 75-90℃ to prepare copper ore raw solution with Cu²+ concentration of 90-95 g / L. (2) Impurity removal and enrichment: The copper ore solution is purified by iron powder replacement method, the pH is controlled at 3.0-4.5, the impurity removal rate is ≥95%, and then enriched by solvent extraction to increase the Cu²+ concentration to 70-90 g / L and the organic phase loading rate is ≥85%; (3) Crystallization and mother liquor circulation: The high-concentration copper sulfate solution is cooled to 20-30℃ and cooled at a rate of 1-3℃ / h. Crystallization takes 10-14 hours. Solid-liquid separation yields copper sulfate pentahydrate with a purity of ≥99.5%. The mother liquor is 100% recycled to the leaching process. (4) Electrolyte preparation and purification: Copper sulfate pentahydrate is dissolved in a mixture of sulfuric acid and pure water to form an electrolyte with Cu²+ 90~100g / L and sulfuric acid 100~110g / L, which is then purified through adsorption resin, diatomaceous earth and activated carbon in sequence. (5) Electrolysis of raw foil and recycling of recycled liquid: The clean liquid is electrolyzed at a current density of 45-55 A / dm² and 50-55 °C. After purification, the recycled liquid of the raw foil is partially leached back to achieve a closed loop of copper acid system with a copper recovery rate of ≥99%.

[0008] Furthermore, the copper ore in step (1) is at least one of chalcopyrite and bornite, with a copper content ≥22% and harmful impurities arsenic, mercury and cadmium content ≤0.01%.

[0009] Furthermore, in step (1), the mixed electrolyte is prepared by mixing the recycled foil and the mother liquor of crystallization at a volume ratio of 1:0.8 to 1.2, replacing the new acid solution.

[0010] Furthermore, step (2) involves iron powder replacement to remove impurities including iron, lead, zinc, nickel, and cobalt, with a total impurity removal rate of ≥96% and a reaction time of 30–45 min.

[0011] Furthermore, in step (2), the volume ratio of extractant to diluent in the organic phase is 1:0.5 to 1, and the back-extractant is a sulfuric acid solution of 180 to 220 g / L.

[0012] Furthermore, in step (3), crystallization is carried out using a continuous cooling crystallizer with a stirring speed of 20-40 r / min, a seed crystal addition amount of 0.5%-1%, and a crystallization particle size of 8-12 mesh.

[0013] Furthermore, in step (4), the adsorption resin treatment capacity is 4-6 m³ / h, and the oil removal rate is ≥99%; the diatomaceous earth filtration accuracy is 1 μm, and the impurity removal rate is ≥98%; the activated carbon filtration TOC removal rate is ≥90%.

[0014] Furthermore, in step (5), the thickness of the electrolytic foil is 6-18 μm, the foil production rate is 1.0-1.5 m / min, and the surface roughness Ra of the cathode roller is ≤0.2 μm.

[0015] Furthermore, in step (5), after the raw foil is recycled and purified, the Cu²+ concentration is maintained at 90-95 g / L, and the proportion recycled to the leaching process is 60%-80%.

[0016] Furthermore, the process is applicable to the production of lithium-ion battery copper foil and high-frequency, high-speed copper foil, reducing overall production costs by more than 25%, achieving an electrolyte recycling rate of ≥98%, and eliminating the discharge of production wastewater.

[0017] The technical effects and advantages of this invention are as follows: (1) Extremely simplified process: Using copper ore directly as raw material, multiple intermediate processes such as cathode copper preparation, smelting and casting, continuous casting, and copper wire melting are omitted, shortening the production process by more than 60%, reducing construction investment by more than 20%, and reducing the land area by 40%.

[0018] (2) High efficiency and low consumption: Copper element recovery rate ≥99%, acid consumption reduced by more than 70%, comprehensive energy consumption reduced by more than 35%, no large amount of new acid added, water resource consumption reduced by 90%, and production cost reduced by more than 25%.

[0019] (3) Green and environmentally friendly: The entire liquid flow is closed-loop, with no production wastewater discharge, waste gas reduction of 80%, solid waste reduction of 60%, hazardous waste production reduction of 90%, and carbon emission reduction of ≥35%, which meets the national "dual carbon" strategy and green manufacturing standards.

[0020] (4) High-end products: The three-level purification system ensures the ultra-high purity of the electrolyte, with impurity content ≤20ppm. It can stably produce 6~18μm lithium battery copper foil and high-frequency high-speed copper foil. The mechanical properties, surface quality and conductivity meet the international first-class standards.

[0021] (5) Stable and controllable: The entire process parameters are automatically and collaboratively controlled, with minimal fluctuations in copper ion concentration, acidity, temperature, and impurity content, resulting in a 50% improvement in batch consistency and making it suitable for large-scale continuous production.

[0022] (6) Strong raw material adaptability: It can be adapted to a variety of raw materials such as chalcopyrite, bornite, low-grade copper ore, copper tailings, and copper-containing solid waste, thus expanding the sources of raw materials and reducing supply chain risks. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1. Flow chart of the integrated production process of the present invention. Detailed Implementation

[0025] The following will refer to the appendices in the embodiments of the present invention. Figure 1The technical solutions in the embodiments of the present invention are clearly and completely described herein. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] The present invention will be further described in detail below with reference to specific embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention. In the embodiments of the present invention, all reagents used are biomedical grade reagents, and all equipment used are conventional biomedical additive manufacturing equipment and conventional laboratory equipment. Experimental methods that do not specify specific conditions are all carried out according to conventional conditions or conditions recommended by the manufacturer.

[0027] An integrated production process from copper ore to electrolytic copper foil includes the following steps: Copper ore crushing and leaching: The copper ore is crushed to below 200 mesh by jaw crusher, cone crusher and ball mill. A composite electrolyte formed by mixing the recycled copper foil from electrolytic copper foil and the mother liquor from crystallization is used as the leaching agent. The concentration of leaching sulfuric acid is controlled at 100-110 g / L and the temperature is controlled at 75-90℃. The copper ore raw solution with a Cu²+ concentration of 90-95 g / L is prepared by continuous stirring leaching to achieve efficient and selective leaching of copper.

[0028] Impurity removal and enrichment: The copper ore solution is purified by iron powder replacement method, and the pH value is controlled at 3.0-4.5 to remove impurity ions such as iron, lead, zinc, nickel and cobalt, with a purification rate of ≥95%. After purification, the solution is enriched by solvent extraction process to increase the copper ion concentration to 70-90 g / L and the organic phase loading rate is ≥85%, so as to achieve deep separation of copper and impurities.

[0029] Crystallization and Mother Liquor Recycling: A high-concentration copper sulfate solution is fed into a continuous cooling crystallizer and slowly cooled to 20-30°C at a rate of 1-3°C / h. Crystallization takes 10-14 hours, and copper sulfate pentahydrate crystals with a purity of ≥99.5% are obtained after solid-liquid separation. The separated mother liquor is 100% recycled to the copper ore leaching process to recover uncrystallized copper ions and sulfuric acid, achieving zero discharge of mother liquor.

[0030] Electrolyte preparation and multi-stage purification: Copper sulfate pentahydrate, pure water and concentrated sulfuric acid are mixed in proportion to prepare an electrolyte with a Cu²+ concentration of 90-100 g / L and a sulfuric acid concentration of 100-110 g / L. The electrolyte is then purified in three stages: adsorption resin, diatomaceous earth filter and activated carbon filter. The adsorption resin removes oil stains, the diatomaceous earth removes suspended particles and additive by-products, and the activated carbon removes TOC. The total impurities after purification are ≤20 ppm.

[0031] Electrolytic foil production and electrolyte recycling: The purified electrolyte is fed into the foil production machine, where electrolytic copper foil is deposited on the surface of the titanium cathode roller. The current density is controlled at 45-55 A / dm², the electrolyte temperature at 50-55℃, the copper foil thickness at 6-18 μm, and the foil production rate at 1.0-1.5 m / min. The recycled electrolyte generated during the foil production process is deeply purified, and part of it is recycled back to the copper ore leaching process, while part is recycled back to the foil production solution preparation stage. This maintains the stability of copper ions and acidity in the entire system, forming a closed-loop circulation of the copper-acid system, with a copper element recovery rate of ≥99%.

[0032] Example 1 6μm lithium battery copper foil production Raw material: Chalcopyrite, Cu content 22%, crushed to 200 mesh, harmful impurities As, Hg, Cd ≤ 0.01%.

[0033] Leaching: The composite leaching solution is raw foil return solution: crystallization mother liquor = 1:1, sulfuric acid concentration 102g / L, temperature 82℃, continuous leaching, copper ore raw solution Cu²+ concentration 92g / L.

[0034] Impurity removal and enrichment: Iron powder was used to replace pH 3.8, the reaction time was 35 min, and the impurity removal rate was 96.2%; solvent extraction of organic phase extractant: diluent = 1:0.8, back-extraction of sulfuric acid 200 g / L, extraction stage 3, back-extraction stage 2, after enrichment Cu²+ concentration was 82 g / L, and organic phase loading rate was 87%.

[0035] Crystallization: Cool to 25℃, cooling rate 2℃ / h, crystallization time 12h, copper sulfate pentahydrate purity 99.6%, mother liquor 100% reflux.

[0036] Electrolyte purification: Cu²⁺ 92g / L, sulfuric acid 105g / L; adsorption resin processing capacity 5m³ / h, diatomaceous earth filtration accuracy 1μm, activated carbon filtration TOC removal rate 92%, total impurities after purification 16ppm.

[0037] Electrolytic foil production: current density 50A / dm², temperature 52℃, copper foil thickness 6μm, foil production rate 1.2m / min; Cu²⁺ concentration in the reflux solution 90g / L, 70% refluxed to the leaching process, 30% refluxed for solution preparation.

[0038] Product performance: tensile strength 367MPa, elongation 12.5%, surface roughness Ra0.21μm, pinhole count 0, meeting GB / T 31367-2015 lithium battery copper foil standard.

[0039] Example 2 Production of 12μm Power Lithium-ion Battery Copper Foil Raw material: Chalcopyrite, Cu content 23.5%, crushed to 220 mesh.

[0040] Leaching: sulfuric acid concentration 108 g / L, temperature 85℃, original solution Cu²+ 94 g / L.

[0041] Impurity removal and enrichment: pH 4.2, impurity removal rate 95.8%; after enrichment Cu²+ 86 g / L, organic phase loading rate 88%.

[0042] Crystallization: Cool to 22℃, crystallize at a rate of 1.5℃ / h for 14h, purity 99.7%.

[0043] Purification: Parameters are the same as in Example 1, with a total impurity content of 14 ppm.

[0044] Raw foil: current density 48A / dm², temperature 53℃, thickness 12μm, rate 1.3m / min; 75% reflux leaching.

[0045] Product performance: tensile strength 352MPa, elongation 14.2%, excellent heat peel strength, suitable for power batteries and energy storage batteries.

[0046] Example 3 18μm high-frequency and high-speed copper foil production Raw material: Bornite, Cu content 25%, crushed to 250 mesh.

[0047] Leaching: sulfuric acid concentration 105 g / L, temperature 88℃, original solution Cu²+ 93 g / L.

[0048] Impurity removal and enrichment: pH 4.0, impurity removal rate 96.5%; after enrichment Cu²+ 88 g / L, organic phase loading rate 89%.

[0049] Crystallization: Cool to 23℃, crystallize at a rate of 2℃ / h for 11h, purity 99.8%.

[0050] Raw foil: current density 52A / dm², temperature 51℃, thickness 18μm, rate 1.4m / min; 80% of the recycled liquid is refluxed for leaching.

[0051] Product performance: Surface roughness Ra0.23μm, conductivity 58.5MS / m, heat resistance and ion migration resistance meet the requirements of IPC-4562 high frequency and high speed copper foil.

[0052] Example 4 Production of 8μm ultrathin high energy density lithium battery copper foil Raw materials: Mixed copper ore (chalcopyrite: bornite = 1:1), Cu content 24%, crushed to 240 mesh.

[0053] Leaching: sulfuric acid concentration 100g / L, temperature 80℃, original solution Cu²+ 91g / L.

[0054] Impurity removal and enrichment: pH 3.5, impurity removal rate 95.5%; after enrichment Cu²+ 80g / L.

[0055] Crystallization: Cool to 20℃, crystallize at a rate of 1℃ / h for 14h, purity 99.5%.

[0056] Raw foil: current density 45A / dm², temperature 50℃, thickness 8μm, speed 1.1m / min; 65% reflux leaching.

[0057] Product performance: tensile strength 375MPa, elongation 11.8%, thickness uniformity ±2%, suitable for high energy density cylindrical batteries.

[0058] Comparative Example 1 Traditional production process The process involves purchasing cathode copper, smelting and casting, continuous casting, air-dissolving copper, and electrolytic foil production. The copper recovery rate is 93.2%, but the overall energy consumption is 38% higher, the production cost is 28% higher, the product batches fluctuate greatly, the impurity content is relatively high, and the wastewater discharge is 15 m³ / ton of copper foil.

[0059] Comparative Example 2 Non-circulation process The mother liquor from crystallization and the recycled liquid from raw foil are not recycled and are directly discharged for treatment. The copper recovery rate is 94.5%, the acid consumption is 2.3 times higher, the wastewater discharge is large, the environmental treatment cost is high, and it does not meet the requirements for near-zero emissions.

[0060] In-depth explanation of process principles and innovations This invention pioneers an integrated mining and foil technology concept, breaking the long-standing industry separation between copper smelting and copper foil manufacturing. It seamlessly couples five major unit operations—wet leaching, extraction metallurgy, crystallization purification, electrolyte purification, and electrolytic foil production—to construct a self-circulating, self-balancing, and self-purifying fully enclosed system. The core innovation lies in waste-to-waste treatment and internal recycling. The recycled liquid from the electrolysis process and the mother liquor from the crystallization process are directly used as leaching agents, saving the cost of purchasing new acid and achieving a closed-loop cycle of copper and acid, eliminating wastewater discharge at the source.

[0061] The leaching process precisely controls acidity and temperature to achieve selective copper leaching, suppressing the dissolution of large amounts of impurities and reducing the load on subsequent impurity removal. Impurity removal employs a combination of chemical displacement and physical extraction: iron powder displacement rapidly removes heavy metal impurities, while solvent extraction selectively enriches copper ions, balancing impurity removal efficiency and copper retention rate. Crystallization controls supersaturation and cooling rate to prepare high-purity, large-particle crystals, avoiding impurity encapsulation and ensuring the purity of the electrolyte raw materials. Purification uses a three-stage gradient removal process, targeting oil stains, inorganic particles, and organic impurities respectively, to achieve ultra-purification of the electrolyte. Electrolytic foil production parameters are linked with front-end circulation parameters to ensure long-term stability of copper ion concentration, acidity, temperature, and impurity content, supporting continuous and stable production of high-end copper foil.

[0062] Key equipment and automation control requirements Crushing system: a combination of three-stage crushing and ball milling, equipped with online particle size monitoring to ensure that more than 98% of the material reaches below 200 mesh, preventing large particles from clogging the pipeline.

[0063] Leaching reactor: Glass-lined continuous stirred tank, acid corrosion resistant, steam heating + automatic temperature control, temperature fluctuation ±1℃, variable frequency stirring.

[0064] Impurity removal extraction system: The displacement reactor is equipped with an online pH meter, and the extraction system uses a mixing and clarification tank. The optimized number of stages ensures the separation effect.

[0065] Crystallization system: OSLO / DTB continuous crystallizer, seed crystal addition interface, supersaturation control ≤0.5g / 100g water to ensure uniform crystals.

[0066] Purification system: macroporous adsorption resin (regenerable), candle diatomaceous earth filter (1μm precision), columnar activated carbon filter (periodic regeneration).

[0067] Foil forming machine: titanium alloy cathode roller, surface polishing Ra≤0.2μm, current density uniformity, spray system, online thickness measurement, thickness uniformity ±3%.

[0068] Automated control system: DCS centralized control, online monitoring of Cu²+, acidity, temperature, flow rate, and impurity content, automatic parameter adjustment, unattended operation.

[0069] Quality control and testing standards Raw material control: Copper ore Cu≥22%, harmful impurities≤0.01%; auxiliary materials meet electronic grade standards.

[0070] Process control: Leachate is tested hourly; after impurity removal, it is tested daily; crystal purity is tested daily; electrolyte impurities are monitored online.

[0071] Product testing: Lithium battery copper foil is tested for tensile strength, elongation, roughness, pinholes, and peel strength; high-frequency and high-speed copper foil is tested for conductivity, heat resistance, and ion migration resistance, all of which meet national and industry standards.

[0072] Environmental and safety features Environmental characteristics: No production wastewater is discharged throughout the entire process, and liquids are 100% recycled; acid mist is discharged in compliance with standards after being sprayed with alkaline solution; leaching residue is comprehensively utilized after stabilization; energy consumption is reduced by 35%, and carbon emissions are reduced by ≥35%.

[0073] Safety features: The system is fully enclosed, explosion-proof, has an emergency discharge pool, over-temperature alarm, and automatic interlock protection to ensure production safety.

[0074] Economic analysis Taking a production capacity of 10,000 tons of high-end electrolytic copper foil per year as an example: Raw material costs: By eliminating the price difference of cathode copper, the cost is reduced by 3,500 yuan per ton; Energy cost: Saves 1200 kWh / ton of electricity, reducing costs by 720 yuan; Chemical costs: Reduced acid consumption and additive losses result in a reduction of 1,800 yuan per ton; Environmental costs: No wastewater treatment fees, reducing costs by 500 yuan per ton; Overall cost: RMB 6,520 per ton, a decrease of over 25%, with an investment payback period of 2.5 years.

[0075] The scope of protection of this invention is not limited to the specific embodiments described above. For those skilled in the art, this invention can have various modifications and improvements. Any modifications, equivalent substitutions, improvements, etc., made within the concept and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An integrated production process from copper ore to electrolytic copper foil, characterized in that, Includes the following steps: (1) Copper ore crushing and leaching: The copper ore is crushed to below 200 mesh and leached with a mixed electrolyte of electrolytic copper foil return liquid and crystallization mother liquor. The sulfuric acid concentration is controlled at 100-110 g / L and the temperature is 75-90℃ to prepare copper ore raw solution with Cu²+ concentration of 90-95 g / L. (2) Impurity removal and enrichment: The copper ore solution is purified by iron powder replacement method, the pH is controlled at 3.0-4.5, the impurity removal rate is ≥95%, and then enriched by solvent extraction to increase the Cu²+ concentration to 70-90 g / L and the organic phase loading rate is ≥85%; (3) Crystallization and mother liquor circulation: The high-concentration copper sulfate solution is cooled to 20-30℃ and cooled at a rate of 1-3℃ / h. Crystallization takes 10-14 hours. Solid-liquid separation yields copper sulfate pentahydrate with a purity of ≥99.5%. The mother liquor is 100% recycled to the leaching process. (4) Electrolyte preparation and purification: Copper sulfate pentahydrate is dissolved in a mixture of sulfuric acid and pure water to form an electrolyte with Cu²+ 90~100g / L and sulfuric acid 100~110g / L, which is then purified through adsorption resin, diatomaceous earth and activated carbon in sequence. (5) Electrolysis of raw foil and recycling of recycled liquid: The clean liquid is electrolyzed at a current density of 45-55 A / dm² and 50-55 °C. After purification, the recycled liquid of the raw foil is partially leached back to achieve a closed loop of copper acid system with a copper recovery rate of ≥99%.

2. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: The copper ore in step (1) is at least one of chalcopyrite and bornite, with a copper content ≥22% and harmful impurities arsenic, mercury and cadmium content ≤0.01%.

3. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: The mixed electrolyte in step (1) is prepared by mixing the recycled foil and the mother liquor of crystallization at a volume ratio of 1:0.8 to 1.2, replacing the new acid solution.

4. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: The step (2) of iron powder replacement to remove impurities and ions includes iron, lead, zinc, nickel and cobalt, with a total impurity removal rate of ≥96% and a reaction time of 30 to 45 minutes.

5. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: In step (2), the volume ratio of extractant to diluent in the organic phase is 1:0.5-1, and the back-extractant is a sulfuric acid solution of 180-220 g / L.

6. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: The crystallization in step (3) is carried out using a continuous cooling crystallizer with a stirring speed of 20-40 r / min, a seed crystal addition of 0.5%-1%, and a crystallization particle size of 8-12 mesh.

7. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: In step (4), the adsorption resin has a processing capacity of 4-6 m³ / h and an oil removal rate of ≥99%; the diatomaceous earth filter has a filtration accuracy of 1 μm and an impurity removal rate of ≥98%; and the activated carbon filter has a TOC removal rate of ≥90%.

8. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: In step (5), the thickness of the electrolytic foil is 6-18 μm, the foil production rate is 1.0-1.5 m / min, and the surface roughness Ra of the cathode roller is ≤0.2 μm.

9. The integrated production process from copper ore to electrolytic copper foil according to claim 1, characterized in that: After purification of the raw foil in step (5), the Cu²+ concentration is maintained at 90-95 g / L, and the proportion of the recycled solution is 60%-80%.

10. An integrated production process from copper ore to electrolytic copper foil according to any one of claims 1 to 9, characterized in that: The process is applicable to the production of lithium-ion battery copper foil and high-frequency, high-speed copper foil, reducing overall production costs by more than 25%, achieving an electrolyte recycling rate of ≥98%, and eliminating the discharge of production wastewater.

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