Anode copper in silver-containing state and preparation method and application thereof

Abstract

The present invention discloses a silver-containing anode copper and its preparation method and application, belonging to the technical field of metallic copper production. The silver-containing anode copper contains 600-2000 ppm of Ag, wherein Ag is distributed in the grain boundaries of copper crystals in the form of a solid compound formed with S and / or Se and / or Te. In the crude copper refining process of conventional copper concentrate or secondary copper resource pyrometallurgy, a silver-fixing agent is added to the crude copper melt to change the occurrence state of silver therein, so that silver is present in a highly stable compound form in the cast copper anode plate. The source of silver in the anode plate is solidified, the dissolution of silver at the anode during the electrolysis process is suppressed, and the total silver (silver ions and floating anode mud) content in the electrolyte is reduced, so that the silver content in the final cathode copper product is less than 2 ppm.

Description

Technical Field

[0001] The invention belongs to the technical field of metallic copper production, and in particular relates to anode copper in a silver-containing state, a preparation method and application thereof. Background Art

[0002] Silver is a valuable byproduct of the copper smelting process. During the electrolytic refining of anode copper to produce cathode copper, the vast majority of the silver in the anode copper is absorbed into the anode mud, but a small amount still finds its way into the cathode copper product, resulting in a silver content as high as 9-13 ppm. Because the price of silver is several dozen times higher than that of copper, and silver is not factored into the cathode copper when it is sold, copper smelters incur hidden economic losses. For example, at a 500,000-ton annual cathode copper production plant, assuming a silver price of 5 yuan per gram, reducing the silver content by 1 ppm can generate an additional 5 million yuan in annual economic benefits. Furthermore, silver is the most difficult metallic impurity to remove during the production of 5N or 6N (5N represents 99.999%) ultrapure copper. Achieving deep pre-removal of silver during the electrolytic refining of 3N or 4N cathode copper can also reduce costs for subsequent ultrapure copper production. In short, reducing the silver content in cathode copper is crucial for improving cathode copper product quality and recovering precious metals.

[0003] During the copper electrolytic refining process, most of the silver in the anode copper exists in the copper matrix in the form of solid solution, and a small amount of silver is included in the complex oxides formed by elements such as Cu-Ag-Pb-As-Se. During the electrolytic refining process of the anode copper, as the anode copper continues to dissolve, the components in the solid solution, including platinum group elements such as silver and gold, dissolve together with the anode copper and enter the anode mud. The silver that enters the electrolyte in the form of ions is discharged and precipitated on the cathode copper surface under the combined action of the electric field and flow field. The other part of the silver exists in the electrolyte in the form of colloidal particles. Most of these colloidal particles are positively charged. Under the action of the electric field, these positively charged colloidal particles gather near the cathode and enter the cathode copper through mechanical inclusion.

[0004] The main methods currently used to reduce the silver content in electrolytic copper cathodes can be divided into two categories:

[0005] 1) This is achieved by controlling the mechanical inclusion of floating anode mud in cathode copper. For example, Chinese patent CN115198309A discloses a method for extracting high-purity copper with low silver content and low sulfur content. This method effectively removes impurities from the electrolyte through electrolysis and purification. Increasing the electrolyte temperature helps reduce the viscosity of the electrolyte, facilitating the sedimentation of floating anode mud and maintaining the copper, acid, and impurity concentrations in the electrolyte within a certain range. Chinese patent CN117210877A also proposes adding transition antimony oxide to the electrolyte to achieve adsorption and sedimentation of floating anode mud, thereby reducing the mechanical inclusion loss of silver particles in cathode copper.

[0006] 2) By deeply removing free silver ions from the electrolyte, the amount of silver ions that enter the cathode copper through electroreduction is reduced. For example, Chinese patent CN116477737A discloses a method for adding an additive to the electrolyte. By deeply removing silver from the electrolyte, the silver ion concentration in the electrolyte is reduced, which helps reduce the reduction and precipitation of silver ions in the cathode copper, thereby reducing the silver content in the cathode copper. Chinese patent CN114150349A discloses a method for reducing the silver content in the cathode copper. Specifically, by circulating and filtering the copper electrolyte, the suspended matter in the electrolyte is separated in time, thereby reducing the silver from entering the cathode copper in the form of discharge precipitation and mechanical adhesion.

[0007] For example, JP2014173116A discloses a method for producing electrolytic copper with low Ag quality by effectively suppressing the Ag concentration of the electrolyte. Solution: The provided method for producing electrolytic copper includes electrolysis in a sulfuric acid-acidic state using a raw copper containing Ag as an anode, while maintaining the anode potential at a level relatively lower than the Ag elution potential.

[0008] For example, JPH01139788A discloses reducing the silver content of electrolytic copper by maintaining dissolved oxygen in the electrolytic solution during copper electrolysis and refining in a sulfate electrolytic cell. The method comprises maintaining dissolved oxygen in the electrolytic solution at ≤3.0 mg / l during re-electrolysis in a sulfate electrolytic cell using electrolytic copper as the anode to produce high-purity electrolytic copper. This method suppresses silver leaching from the anode and prevents silver from entering the electrolytic copper due to electrochemical contamination. High-purity electrolytic copper with a silver content of ≤0.2 ppm, preferably ≤0.1 ppm, can be produced. Lowering the temperature effectively suppresses silver leaching.

[0009] For example, CN117604575A discloses a method for producing cathode copper by microwave-assisted continuous electrorefining of high-gold, silver, and copper plates, which relates to the field of copper electrorefining technology. The method comprises the following steps: using high-gold, silver, and copper plates as anodes for copper electrorefining in an electrolyte, and applying microwaves to the electrolyte during the electrolysis process; circulating and purifying the electrolyte during the electrolysis process, which includes continuous electrolyte discharge, purification, and recirculation. The silver content of the high-gold, silver, and copper plates is 304.57 to 998.91 g / t, and the gold content is 50.72 to 69.36 g / t. By applying microwaves during the electrolysis process to purify the electrolyte and then circulating it, the microwave vibrations suspend a large amount of anode mud in the electrolyte. This is then separated, collected, and purified in real time, improving the purity of the cathode copper and the gold and silver recovery rate. Furthermore, the surface grains of the copper are refined, improving the surface quality of the cathode copper.

[0010] For example, CN110699708A discloses a method for reducing the silver content of electrolytic cathode copper, which comprises the following steps: (1) adding an electrolyte to an electrolytic cell, and then adding hydrochloric acid to adjust the chloride ion concentration of the electrolyte to 0.03-0.07 g / L; the concentration of sulfuric acid in the electrolyte is 170-180 g / L; in the electrolyte, the amount of Avitron added is 10-12 g / t.Cu, the amount of gelatin added is 20-30 g / t.Cu, and the amount of thiourea added is 20-30 g / t.Cu; (2) placing a high-copper and low-impurity anode plate in the electrolytic cell for electrolysis to obtain electrolytic cathode copper, and the current density is 280-320 A / m 2 The electrolysis temperature is 61-63°C, and the circulation rate of the electrolyte in a single electrolytic cell is 25-28 L / min. The method of the present invention can effectively reduce the silver content in cathode copper, improve the silver recovery rate, and reduce the loss of precious metals.

[0011] Although the above methods can reduce the silver content in cathode copper to a certain extent, they all require the addition of additional silver removal and filtration steps outside the electrolyte tank to the existing electrolytic refining process, which is not conducive to equipment modification and process parameter adjustment in the electrolytic production workshop, and is difficult to be applied in actual production. Summary of the Invention

[0012] 1. Problem to be solved

[0013] In response to the technical problem of high silver content in cathode copper, the present invention aims to provide anode copper with silver present in a state to reduce the silver content in electrolytic cathode copper, thereby improving the quality of cathode copper.

[0014] Another object of the present invention is to provide a method for preparing anode copper in a silver-containing state.

[0015] Another object of the present invention is to provide anode copper in a silver-containing state for use in electrolytic refined copper.

[0016] 2. Technical solution

[0017] In order to solve the above problems, the technical solutions adopted by the present invention are as follows:

[0018] A first aspect of the present invention provides a silver-containing anode copper, the main components of which are copper and other impurities, and which contains 600-2000 ppm of Ag, wherein Ag is distributed in the grain boundaries of copper crystals in the form of a solid compound formed with S and / or Se and / or Te.

[0019] According to any embodiment of the first aspect of the present invention, the silver in the solid compound state includes at least one of Ag2S, Ag2Se, Ag2Te, AgCuS, AgCuSe, and AgCuTe.

[0020] A second aspect of the present invention provides a method for preparing anode copper in a silver-containing state as described in the first aspect, comprising the following steps: in a conventional copper concentrate or secondary copper resource pyrometallurgical crude copper refining process, adding a compound or mixture containing at least one element of selenium, tellurium, and sulfur to the crude copper melt as a silver-fixing agent, and then casting and cooling to obtain anode copper in a silver-containing state.

[0021] According to any embodiment of the second aspect of the present invention, the silver fixing agent is at least one of elemental S, Cu2S, CuS, FeS, matte, Se, Cu2Se, CuSe, Te, CuTe, and Cu2Te, and preferably at least one of Cu2S, Se, Cu2Se, CuSe, Cu2Se, Te, and Cu2Te.

[0022] According to any embodiment of the second aspect of the present invention, the amount of the silver fixing agent added satisfies the molar ratio of the total molar amount of Se, Te, and S to the molar amount of Ag in the anode copper of 0.2-1.5, preferably 0.3-1.2.

[0023] According to any embodiment of the second aspect of the present invention, the silver-present anode copper has an Ag content of 600-2000 ppm, an S content of 35-900 ppm, a Se content of 80-2200 ppm, and a Te content of 140-3600 ppm.

[0024] According to any embodiment of the second aspect of the present invention, in the crude copper refining process, conventional copper concentrate or secondary copper resource pyrometallurgy is used, wherein the copper concentrate is a sulfide copper concentrate containing at least one of chalcopyrite, chalcocite, bornite, and thioarsenic copper; and the secondary copper resource is at least one of waste circuit boards, waste lithium-ion batteries, and waste copper.

[0025] According to any embodiment of the second aspect of the present invention, the pyrometallurgical process comprises at least one of top-blown furnace copper smelting, side-blown furnace copper smelting, bottom-blown furnace copper smelting, and flash copper smelting processes.

[0026] The third aspect of the present invention provides an application of the anode copper described in the first aspect and the anode copper in a silver-containing state obtained by the method described in the second aspect, which is used as an electrolytic anode for electrolytic refining to produce cathode copper, and the silver content of the cathode copper obtained after electrolysis is <2ppm.

[0027] According to any embodiment of the third aspect of the present invention, the electrolytic refining conditions are: the cathode plate is pure copper or stainless steel; the electrolyte composition is Cu 2+ Concentration 15-50g / L, preferably 35-45g / L, H2SO4 concentration 100-200g / L, preferably 150-180g / L; current density 250-400A / m 2, preferably 280-350A / m 2 ; The plate spacing is 10-30mm, preferably 15-25mm; the electrolysis temperature is 40-70℃, preferably 50-65℃.

[0028] In combination with the technical solution of the present invention, the present invention has the following characteristics:

[0029] (1) Easy to operate and well connected with existing processes

[0030] The current copper electrolytic refining process mainly suppresses the precipitation of silver-containing particles and silver ions in the cathode copper by optimizing the electrolytic process parameters, strengthening the precision filtration outside the electrolytic cell to reduce the content of floating anode mud in the electrolyte, and removing silver deep outside the electrolytic cell, thereby reducing the silver content in the cathode copper. However, all of these methods require significant changes to the existing complex copper electrolytic refining equipment and process parameters, and cannot fundamentally solve the problem of high silver content in the cathode copper. The present invention adds a small amount of silver-fixing agent to the crude copper refining process before copper electrolytic refining, so that the silver in the refined anode copper reacts with the silver-fixing agent to form a stable compound, and anode copper in a silver-containing state can be prepared; therefore, compared with the existing method, the present technology does not require the modification of the existing copper electrolytic refining equipment and process parameters, and the prepared anode copper can be directly used in the existing electrolytic refining process.

[0031] (2) Significantly reduce the silver content in cathode copper and improve economic benefits

[0032] In the prior art, most of the silver in anode copper is mainly divided into: the vast majority of silver exists in the copper matrix in the form of solid solution, and a small amount of silver exists in the form of oxide. The silver in the solid solution and the oxidized silver are easily oxidized and dissolved into the electrolyte during the electrolysis process, becoming the main source of silver in the electrolyte. In addition, this part of the silver ions will also react with Cl in the electrolyte. - The formation of extremely fine AgCl insoluble particles increases the content of floating anode mud, which will lead to an increase in the silver content in the cathode copper.

[0033] During the production of the anode copper according to the present invention, due to the effect of the additional addition of a silver-fixing agent containing Se, and / or Te, and / or S, during the crude copper refining and copper anode plate casting processes, the solid solution silver and oxidized silver originally present in the copper matrix react with the Se, and / or Te, and / or S in the silver-fixing agent to form extremely stable large-particle compounds such as Ag2Se, Ag2Te, Ag2S, AgCuTe, and AgCuS. These substances are difficult to dissolve during the electrolysis process and are directly precipitated in the anode mud. This can inhibit the dissolution of silver during the electrolytic refining process and the secondary in-situ precipitation to form extremely fine floating anode mud, thereby achieving deep extraction of silver from the source of the electrolyte, thereby reducing the electrochemical reduction and mechanical inclusion content of silver in the cathode copper product. Therefore, the silver content in the cathode copper produced by the electrolytic production of the new anode plate invented by this technology can be as low as below 2ppm, which is at least 60% lower than the current cathode copper silver content of 9-13ppm. Taking a copper smelting enterprise with an annual cathode copper output of 500,000 tons as an example, based on the calculation of silver at 5 yuan / g, the economic value of silver products can be increased by 40 million yuan for the enterprise each year.

[0034] (3) No impurities from outside the system are introduced

[0035] The silver-fixing agent used in the preparation of the novel anode copper according to the present invention is at least one of Se, Te, Cu2Se, CuSe, CuTe, Cu2Te, Cu2S, CuS, FeS, and matte. The raw materials are all commonly used intermediate process products or by-products in the copper smelting system, and no new foreign impurity elements are introduced into the electrolysis process. Therefore, the raw material cost is extremely low, the impact on the electrolytic refining process is small, and the operation effect is stable.

[0036] 3. Beneficial effects

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The anode copper with silver occurrence state of the present invention comprises a process of adding a silver-fixing agent to a blister copper melt during a conventional copper concentrate or secondary copper resource pyrometallurgical blister copper refining process to change the occurrence state of silver therein, so that the silver exists in a cast copper anode in an extremely stable chemical form. By solidifying the silver in the copper anode at the source, the dissolution of silver in the copper anode during the electrolysis process is suppressed, and the total silver content (silver ions and floating anode mud) in the electrolyte is reduced, so that the silver content in the final cathode copper product is less than 2 ppm. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that these drawings are designed for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, unless otherwise specified, these drawings are intended only to conceptually illustrate the structures described herein and are not necessarily drawn to scale.

[0040] Figure 1 The anode copper in the silver-occurring state containing the Ag-S compound according to Example 1 of the present invention;

[0041] Figure 2 The anode copper in the silver-occurring state containing the Ag-Se compound according to Example 2 of the present invention;

[0042] Figure 3 The anode copper in the silver-occurring state containing the Ag-Te compound according to Example 3 of the present invention;

[0043] Figure 4 This is the anode copper in the silver-containing state in the comparative example. DETAILED DESCRIPTION

[0044] Exemplary embodiments of the present invention are described in detail below. Although these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be implemented and that various changes may be made to the invention without departing from the spirit and scope of the invention. The following more detailed description of the embodiments of the invention is not intended to limit the scope of the claimed invention, but is merely for illustrative and non-limiting purposes, to describe the features and characteristics of the invention, to set forth the best mode for carrying out the invention, and to enable those skilled in the art to practice the invention. Therefore, the scope of the invention is limited solely by the appended claims.

[0045]

Anodic copper in silver-containing state

[0046] Existing technologies only consider controlling the silver content in the electrolyte, and fail to strictly control the dissolution of silver from the anode copper. The vast majority of silver in existing anode copper exists in a solid solution state, which is easily oxidized and dissolved into silver ions during the electrolysis process. These silver ions then migrate to the cathode, are reduced, and precipitate into the cathode copper product. This fails to fundamentally address the problem of high silver content in cathode copper. The present invention adds a small amount of a silver-fixing agent to the crude copper refining process prior to copper electrolytic refining, allowing the silver in the refined anode copper to react with the silver-fixing agent to form a stable compound, thereby producing anode copper in a silver-containing state.

[0047] The anode copper in the silver-containing state of the present invention satisfies at least one of the following conditions:

[0048] 1) The main components are copper and other impurities, including 600-2000 ppm of Ag, in which Ag is distributed in the grain boundaries of copper crystals in the form of solid compounds formed with S and / or Se and / or Te;

[0049] 2) The solid compound silver includes at least one of Ag2S, Ag2Se, Ag2Te, AgCuS, AgCuSe, and AgCuTe.

[0050] The solid solution silver and oxidized silver present in the copper matrix will form extremely stable large-particle compounds such as Ag2Se, Ag2Te, Ag2S, AgCuTe, and AgCuS with Se, Te, and S in the silver-fixing agent. These substances are difficult to dissolve during the electrolysis process and directly precipitate in the anode mud, which can inhibit the dissolution of silver and secondary in-situ precipitation in the electrolytic refining process from the source to form extremely fine floating anode mud, thereby reducing the electrochemical reduction and mechanical inclusion of silver in the cathode copper product, and realizing the deep removal of electrolyte silver from the source.

[0051] Preparation method of anode copper in silver-containing state

[0052] The method comprises the following steps: in a conventional copper concentrate or secondary copper resource pyrometallurgical crude copper refining process, adding a compound or mixture containing at least one element among selenium, tellurium and sulfur as a silver-fixing agent to the crude copper melt, and then obtaining anode copper in a silver-containing state after casting and cooling.

[0053] At least one of the following conditions must be met:

[0054] 1) The silver fixing agent is at least one of elemental S, Cu2S, CuS, FeS, matte, Se, Cu2Se, CuSe, Te, CuTe, and Cu2Te, preferably at least one of Cu2S, Se, Cu2Se, CuSe, Cu2Se, Te, and Cu2Te.

[0055] 2) The amount of the silver-fixing agent added satisfies the molar ratio of the total molar amount of Se, Te, and S to the molar amount of Ag in the anode copper of 0.2-1.3, preferably, preferably 0.3-0.8.

[0056] 3) The silver-containing anode copper has an Ag content of 600-2000 ppm, a S content of 35-900 ppm, a Se content of 80-2200 ppm, and a Te content of 140-3600 ppm.

[0057] 4) In the crude copper refining process, conventional copper concentrate or secondary copper resource pyrometallurgy is used, wherein the copper concentrate is a sulfide copper concentrate containing at least one of chalcopyrite, chalcocite, bornite, and thioarsenite; and the secondary copper resource is at least one of waste circuit boards, waste lithium-ion batteries, and waste copper.

[0058] 5) The pyrometallurgical process includes at least one of top-blown furnace copper smelting, side-blown furnace copper smelting, bottom-blown furnace copper smelting, and flash copper smelting processes.

[0059]

Application of anode copper with silver presence

[0060] The anode copper of the present invention is used as an electrolytic anode plate for electrolytic refining to produce cathode copper. The silver content of the cathode copper obtained after electrolysis is less than 2ppm, which is at least 60% lower than the silver content of 9-13ppm in the cathode copper of the prior art.

[0061] The specific electrolytic refining conditions are: the cathode plate is pure copper or stainless steel; the electrolyte composition is Cu 2+ Concentration 15-50g / L, preferably 35-45g / L, H2SO4 concentration 100-200g / L, preferably 150-180g / L; current density 250-400A / m 2 , preferably 280-350A / m 2 ; The plate spacing is 10-30mm, preferably 15-25mm; the electrolysis temperature is 40-70℃, preferably 50-65℃.

[0062] A detailed description and exemplary embodiments of the present invention are described below.

[0063] Example 1

[0064] The method for preparing anode copper in a silver-containing state of this embodiment comprises the following steps:

[0065] In the refining process of blister copper obtained by flash smelting furnace pyrometallurgy of chalcopyrite concentrate, Cu2S is added to the blister copper melt as a silver-fixing agent. The amount of Cu2S added satisfies the molar ratio of Cu2S to Ag in the anode copper of 1.2. After casting and cooling, the anode copper in the silver-containing state is obtained.

[0066] The anode copper prepared above is used for electrolytic refining to produce cathode copper. The cathode copper obtained after electrolysis is as follows:

[0067] Electrolytic refining conditions are: cathode plate is pure copper or stainless steel; electrolyte composition is Cu 2+ Concentration 45g / L, H2SO4 concentration 180g / L, current density 330A / m 2 , the plate spacing is 20 mm, and the electrolysis temperature is 60°C.

[0068] The detection method of S, Se and Te in anode copper is in accordance with GB / T 5121 Chemical Analysis Method for Copper and Copper Alloys. The occurrence state of silver in anode copper is determined by electron scanning microscopy. Figure 1 As shown, it contains Ag2S.

[0069] Method for determining the silver content in the cathode copper obtained by electrolysis: The silver content is determined according to GB / T 5121 chemical analysis method for high-purity cathode copper - mercapto cotton separation - flame atomic absorption spectrometry, and the total silver content in the cathode copper is finally obtained. The final silver content in the cathode copper obtained by electrolysis is 1.4 ppm.

[0070] Example 2

[0071] The method for preparing anode copper in a silver-containing state of this embodiment comprises the following steps:

[0072] In the refining process of blister copper obtained by flash smelting furnace pyrometallurgy of chalcopyrite concentrate, Cu2Se is added to the blister copper melt as a silver-fixing agent. The amount of Cu2Se added satisfies the molar ratio of Cu2Se to Ag in the anode copper of 1.2. After casting and cooling, the anode copper in a silver-containing state is obtained.

[0073] Electrolytic refining conditions are: cathode plate is pure copper or stainless steel; electrolyte composition is Cu 2+ Concentration 45g / L, H2SO4 concentration 180g / L, current density 330A / m 2 , the plate spacing is 20 mm, and the electrolysis temperature is 60°C.

[0074] The Se content in the obtained anode copper was detected according to GB / T 5121 Chemical Analysis Methods for Copper and Copper Alloys. The silver content in the anode copper was determined by electron scanning microscopy. Figure 2 As shown, it contains Ag2Se.

[0075] Method for determining the silver content in the cathode copper obtained by electrolysis: The silver content is determined according to GB / T 5121 chemical analysis method for high-purity cathode copper - mercapto cotton separation - flame atomic absorption spectrometry, and the total silver content in the cathode copper is finally obtained. The final silver content in the cathode copper obtained by electrolysis is 1.3 ppm.

[0076] Example 3

[0077] The method for preparing anode copper in a silver-containing state of this embodiment comprises the following steps:

[0078] In the refining process of blister copper obtained by flash smelting furnace pyrometallurgy of chalcopyrite concentrate, Cu2Te is added to the blister copper melt as a silver-fixing agent. The amount of Cu2Te added satisfies the molar ratio of Cu2Te to Ag in the anode copper of 1.2. After casting and cooling, the anode copper in the silver-containing state is obtained.

[0079] Electrolytic refining conditions are: cathode plate is pure copper or stainless steel; electrolyte composition is Cu 2+ Concentration 45g / L, H2SO4 concentration 180g / L, current density 330A / m 2 , the plate spacing is 20 mm, and the electrolysis temperature is 60°C.

[0080] The Te content in the obtained anode copper was determined according to GB / T 5121 Chemical Analysis Methods for Copper and Copper Alloys. The silver content in the anode copper was determined by electron scanning microscopy. Figure 3 As shown, it contains Ag2Te.

[0081] Method for determining the silver content in the cathode copper obtained by electrolysis: The silver content was determined according to GB / T 5121 chemical analysis method for high-purity cathode copper - mercapto cotton separation - flame atomic absorption spectrometry, and the total silver content in the cathode copper was finally obtained. The final silver content in the cathode copper obtained by electrolysis was 0.9 ppm.

[0082] Example 4

[0083] The method for preparing anode copper in a silver-containing state of this embodiment comprises the following steps:

[0084] In the refining process of blister copper obtained by flash smelting furnace pyrometallurgy of chalcopyrite concentrate, CuSe is added to the blister copper melt as a silver-fixing agent. The amount of CuSe added satisfies the molar ratio of CuSe to Ag in the anode copper of 1.2. After casting and cooling, the anode copper in a silver-containing state is obtained.

[0085] Electrolytic refining conditions are: cathode plate is pure copper or stainless steel; electrolyte composition is Cu 2+ Concentration 45g / L, H2SO4 concentration 180g / L, current density 330A / m 2 , the plate spacing is 20 mm, and the electrolysis temperature is 60°C.

[0086] The detection method for S, Se and Te in anode copper shall be in accordance with GB / T 5121 Chemical analysis method for copper and copper alloys.

[0087] Method for determining the silver content in the cathode copper obtained by electrolysis: The silver content is determined according to GB / T 5121 chemical analysis method for high-purity cathode copper - mercapto cotton separation - flame atomic absorption spectrometry, and the total silver content in the cathode copper is finally obtained. The final silver content in the cathode copper obtained by electrolysis is 1.5 ppm.

[0088] Comparative Example

[0089] The method for preparing the anode copper of this embodiment comprises the following steps:

[0090] In the refining process of blister copper obtained by flash smelting pyrometallurgy of chalcopyrite concentrate, no silver-fixing agent is added to the blister copper melt, and then anode copper is obtained after casting and cooling.

[0091] Electrolytic refining conditions are: cathode plate is pure copper or stainless steel; electrolyte composition is Cu 2+Concentration 45g / L, H2SO4 concentration 180g / L, current density 330A / m 2 , the plate spacing is 20 mm, and the electrolysis temperature is 60°C.

[0092] The detection method of S, Se and Te in anode copper is in accordance with GB / T 5121 Chemical Analysis Method for Copper and Copper Alloys. The occurrence state of silver in anode copper is determined by electron scanning microscopy. Figure 4 shown.

[0093] Method for determining the silver content in cathode copper obtained by electrolysis: The silver content is determined by using GB / T 5121 chemical analysis method for high-purity cathode copper - mercapto cotton separation - flame atomic absorption spectrometry to obtain the total silver content in the cathode copper. The silver in the cathode copper exists in the form of dispersed fine elemental silver or copper-silver oxide particles. The final silver content in the cathode copper obtained by electrolysis is 12.5 ppm.

[0094] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, they can make several improvements and modifications without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A copper anode in a silver-containing state, characterized in that: Contains 600-2000 ppm of Ag, wherein Ag is distributed in the grain boundaries of copper crystals in the form of solid compounds formed with S and / or Se and / or Te.

2. The anode copper in a silver-containing state according to claim 1, characterized in that: The silver in the solid compound state includes at least one of Ag2S, Ag2Se, Ag2Te, AgCuS, AgCuSe, and AgCuTe.

3. A method for preparing anode copper in a silver-occurring state according to claim 1 or 2, characterized in that: The following steps are involved: During the crude copper refining process, a compound or mixture containing at least one element among Se, Te and S is added to the crude copper melt as a silver-fixing agent, and then the anode copper in a silver-containing state is obtained after casting and cooling.

4. The method for preparing anode copper according to claim 3, wherein: The silver fixing agent is at least one of elemental S, Cu2S, CuS, FeS, matte, Se, Cu2Se, CuSe, Te, CuTe, and Cu2Te.

5. The method for preparing anode copper according to claim 4, wherein: The amount of the silver-fixing agent added satisfies the molar ratio of the total molar amount of Se, Te, and S to the molar amount of Ag in the anode copper of 0.2-1.

3.

6. The method for preparing anode copper according to claim 5, characterized in that: The amount of the silver-fixing agent added satisfies the molar ratio of the total molar amount of Se, Te, and S to the molar amount of Ag in the anode copper of 0.3-0.

8.

7. The method for preparing anode copper according to claim 6, wherein: The anode copper in the silver-containing state has an Ag content of 600-2000 ppm, an S content of 35-900 ppm, a Se content of 80-2200 ppm, and a Te content of 140-3600 ppm.

8. The method for preparing anode copper according to claim 7, wherein: In the crude copper refining process, conventional copper concentrate or secondary copper resource pyrometallurgy is used, wherein the copper concentrate is a sulfide copper concentrate containing at least one of chalcopyrite, chalcocite, bornite, and thioarsenic copper; and the secondary copper resource is at least one of waste circuit boards, waste lithium-ion batteries, and waste copper.

9. The method for preparing anode copper according to claim 8, characterized in that: The pyrometallurgical process includes at least one of top-blown furnace copper smelting, side-blown furnace copper smelting, bottom-blown furnace copper smelting, and flash copper smelting processes.

10. Use of the anode copper according to any one of claims 1 to 2, and the anode copper obtained by any one of the methods 3 to 9, as an electrolytic anode for electrolytic refining to produce cathode copper, wherein the silver content of the cathode copper obtained after electrolysis is less than 2 ppm.

11. The use according to claim 10, characterized in that Electrolytic refining conditions are: cathode plate is pure copper or stainless steel, electrolyte composition is Cu 2+ Concentration 15-50g / L, H2SO4 concentration 100-200g / L, current density 250-400A / m 2 , the plate spacing is 10-30mm, and the electrolysis temperature is 40-70℃.

12. The use according to claim 11, characterized in that The electrolyte composition is Cu 2+ Concentration 35-45g / L, H2SO4 concentration 150-180 g / L, current density 280-350 A / m 2 , the plate spacing is 15-25mm, and the electrolysis temperature is 50-65℃.

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