Process for recovering copper from bismuth matte by total wet method

Abstract

The application discloses a process for recovering copper from bismuth copper matte by a full-wet method. The process provides process conditions for selectively leaching copper in bismuth copper matte in an acidic solution under the condition of an oxidizing agent, so that the copper in the bismuth copper matte enters the acidic solution, and other valuable elements such as gold, silver, lead, bismuth and antimony in the bismuth copper matte are not leached basically. The obtained copper-containing leaching solution can be directly electro-deposited to prepare electrolytic copper products meeting the national standard A grade without purification and impurity removal; and the leaching residue containing valuable metals such as gold, silver, lead, bismuth and antimony can be returned to a lead anode slime pyrometallurgical system for recovery. The process can realize high recovery rate of valuable metals such as gold, silver, lead, bismuth and antimony in the bismuth copper matte, low acid consumption, no generation of three wastes in the process, and green recovery of the valuable metals in the bismuth copper matte.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metal hydrometallurgy, and particularly relates to a process for recovering copper from bismuth matte using a fully hydrometallurgical method. Background Technology

[0002] Bismuth matte is a product of the pyrometallurgical refining process of bismuth, containing large amounts of elements such as copper, lead, antimony, and sulfur. The chemical composition of the bismuth matte used in this experiment is mainly as follows: Cu 20-40%, Fe 0.5-10%, S 5-15%, Pb 8-40%, Sb 0.5-15%, Ag 2-8%, Bi 0.5-7%, and As 0.1-2.0%. Copper mainly exists in the form of sulfides such as Cu₂S, CuS, Cu₂Sb, and Cu₉S₅. A suitable oxidant needs to be added to fully oxidize the copper-containing sulfide ore before the copper can be efficiently leached into the acidic leachate.

[0003] Currently, the main processes for processing copper matte include pyrometallurgical, pyrometallurgical-hydrometallurgical combined, and fully hydrometallurgical processes. For example, patent CN116574920A discloses a pyrometallurgical process for producing crude copper by converter blowing of high-grade copper matte. By adding copper matte and cold material in batches and adding flux in small amounts multiple times, copper matte can be blown into crude copper. However, this process has disadvantages such as long process, low metal recovery rate, and environmental pollution. Moreover, this process is not suitable for bismuth copper matte with low copper grade because the sulfur content is low and the low concentration of SO2 generated cannot be effectively recovered. The pyrometallurgical-hydrometallurgical combined process mainly involves first oxidizing and roasting copper matte, then leaching the roasting residue with sulfuric acid to obtain copper sulfate solution and leaching residue rich in lead sulfate. Finally, the copper in the copper sulfate solution is recovered (paper "Solvent Extraction of Copper from Acid Leaching Solution of Lead Copper Mat Oxidation Roasting Product, Hydrometallurgy, 2017, (5), 388-390"). The roasting stage of this process also has the problem of low concentration SO2 being difficult to recover and utilize, and its process flow is long and energy consumption is high. The wet leaching process mainly includes pressure leaching and atmospheric pressure leaching. For example, the methods disclosed in patents CN114934182A, CN101225476B, and CN104789783B all involve adding an appropriate oxidant to subject the ground copper matte to acidic pressure oxidative leaching. Patents CN102586600B and CN102230083B use an alkaline system for pressure oxidative leaching of copper matte, effectively separating valuable elements from the raw material. However, pressure leaching not only requires sophisticated equipment but also presents operational challenges. There are certain risks involved; Patent CN105543479B uses concentrated sulfuric acid and dilute sulfuric acid to perform two-stage atmospheric pressure oxidation leaching of copper matte. After purification, the leaching solution is subjected to copper electrowinning treatment. Since the first stage uses concentrated sulfuric acid leaching, the leaching solution contains more metallic impurities such as Bi and Fe, which increases the purification process; Patent CN102051478B uses sulfuric acid and sodium chloride to oxidize and leach lead matte, and uses iron filings to reduce the copper-containing leaching solution to obtain sponge copper. This process introduces a large number of Cl ions into the replacement tail liquid, increasing the burden on wastewater treatment. Summary of the Invention

[0004] This invention discloses a fully wet process for recovering copper from bismuth matte, in order to solve any of the above-mentioned and other potential problems in the prior art.

[0005] To achieve the above objectives, the technical solution of the present invention is: a process for the complete wet recovery of copper from bismuth matte, which specifically includes the following steps:

[0006] S1) The blocky bismuth matte is crushed and ground to a certain particle size to obtain bismuth matte powder;

[0007] S2) The bismuth matte powder obtained in S1) is mixed with an acidic solvent in a certain proportion, stirred continuously at a certain rate, heated to a certain temperature, kept at the temperature for a certain time, and after leaching, filtered to obtain leaching residue and copper-containing acidic leachate.

[0008] S3) After adding a certain amount of additive to the copper-containing acidic leaching solution obtained in S2), electrowinning is performed directly at an appropriate current density to obtain electrowinning copper.

[0009] Furthermore, in S1), the particle size is more than 80% smaller than 200 mesh.

[0010] Furthermore, in S2), the solid-liquid ratio of bismuth matte to acidic solvent is 1 kg: 6.0 L to 10 L, the stirring speed is above 100 r / min, oxidant is continuously added during the leaching process, the pressure is atmospheric pressure, the reaction temperature is 70℃ to 95℃, and the holding time is 6 h to 15 h.

[0011] Furthermore, the acidic solvent contains sulfuric acid at a concentration of 1.6 mol / L to 2.3 mol / L; copper ion at a concentration of 5-25 g / L; bismuth ion at a concentration of 0.5-3 g / L; iron ion at a concentration of 0-3 g / L; and antimony ion at a concentration of 0-0.3 g / L.

[0012] Furthermore, the oxidant is H2O2 and oxygen;

[0013] The amount of H2O2 added is 0.1 to 0.5 times the weight of bismuth matte; oxygen is added at a flow rate of 1 to 10 L / min per kilogram of bismuth matte powder.

[0014] Furthermore, the amount of additive added in S3) is 20-400 g / t copper; the current density is controlled at 150 A / m. 2 ~300A / m 2 .

[0015] Furthermore, the additive is one or a combination of several of the following: bone glue, gelatin, guar gum, casein, thiourea, polyethylene glycol, chloride ions, cobalt sulfate, and avermectin.

[0016] Furthermore, in the electrolytic cell of the electrowinning process, the anode is a lead alloy plate and the cathode is a stainless steel plate, and the electrolytic waste liquid can be returned to be mixed with acidic solvent for recycling.

[0017] Furthermore, the copper leaching rate of the process is not less than 94%, the bismuth and antimony leaching rates are close to 0, and the purity of the electrowinning copper obtained after electrowinning of the copper sulfate leaching solution is 99.995%.

[0018] An electroplated copper, which is prepared using the above-described process.

[0019] The present invention has the following advantages:

[0020] 1) Copper has a good separation effect from other valuable metals. No less than 94% of the copper in bismuth matte can be selectively leached and separated, while valuable metals such as gold, silver, lead, bismuth and antimony are basically enriched in the slag.

[0021] 2) The production process is short, and the copper in bismuth matte can be effectively separated by a single step of atmospheric pressure oxidation leaching.

[0022] 3) The sulfuric acid consumption is low, and the lean electrolyte solution can be reused to prepare acidic leaching agents for leaching bismuth matte.

[0023] 4) All reactions are carried out at atmospheric pressure, which reduces the requirements for equipment materials and the investment in equipment is small.

[0024] 5) The reaction raw materials are highly adaptable, energy consumption is low, no waste is generated, and it is environmentally friendly. It can economically and efficiently recover all valuable metals in bismuth matte, and achieve zero discharge of waste residue and wastewater from lead smelting enterprises.

[0025] 6) This method has low requirements for leaching conditions, low requirements for equipment, short process flow, and is easy to operate. The resulting leachate can be directly electrolyzed and deposited to generate electrolytic copper products that meet the national standard Grade A without purification treatment. Attached Figure Description

[0026] Figure 1 This is a process flow diagram of a fully wet process for recovering copper from bismuth matte according to the present invention. Detailed Implementation

[0027] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] like Figure 1 As shown, the present invention discloses a fully wet process for recovering copper from bismuth matte, which specifically includes the following steps:

[0029] S1) The blocky bismuth matte is crushed and ground to a certain particle size to obtain bismuth matte powder;

[0030] S2) The bismuth matte powder obtained in S1) is mixed with an acidic solvent in a certain proportion, stirred continuously at a certain rate, heated to a certain temperature, kept at the temperature for a certain time, and after leaching, filtered to obtain leaching residue and copper-containing acidic leachate.

[0031] S3) After adding a certain amount of additive to the copper-containing acidic leaching solution obtained in S2), electrowinning is performed directly at an appropriate current density to obtain electrowinning copper.

[0032] Furthermore, in S1), the particle size is more than 80% smaller than 200 mesh.

[0033] Furthermore, in S2), the solid-liquid ratio of bismuth matte to acidic solvent is 1 kg: 6.0 L to 10 L, the stirring speed is above 100 r / min, oxidant is continuously added during the leaching process, the pressure is atmospheric pressure, the reaction temperature is 70℃ to 95℃, and the holding time is 6 h to 15 h.

[0034] Furthermore, the acidic solvent contains sulfuric acid at a concentration of 1.6 mol / L to 2.3 mol / L; copper ion at a concentration of 5-25 g / L; bismuth ion at a concentration of 0.5-3 g / L; iron ion at a concentration of 0-3 g / L; and antimony ion at a concentration of 0-0.3 g / L.

[0035] Furthermore, the oxidant is H2O2 and oxygen;

[0036] The amount of H2O2 added is 0.1 to 0.5 times the weight of bismuth matte; oxygen is added at a flow rate of 1 to 10 L / min per kilogram of bismuth matte powder.

[0037] Furthermore, the amount of additive added in S3) is 20-400 g / t copper; the current density is controlled at 150 A / m. 2 ~300A / m 2 .

[0038] Furthermore, the additive is one or a combination of several of the following: bone glue, gelatin, guar gum, casein, thiourea, polyethylene glycol, chloride ions, cobalt sulfate, and avermectin.

[0039] Furthermore, in the electrolytic cell of the electrowinning process, the anode is a lead alloy plate and the cathode is a stainless steel plate, and the electrolytic waste liquid can be returned to be mixed with acidic solvent for recycling.

[0040] Furthermore, the copper leaching rate of the process is not less than 94%, the bismuth and antimony leaching rates are close to 0, and the purity of the electrowinning copper obtained after electrowinning of the copper sulfate leaching solution is 99.995%.

[0041] An electroplated copper, which is prepared using the above-described process.

[0042] Example 1

[0043] This embodiment provides a method for recovering copper by acidic leaching of bismuth matte, the process flow of which is as follows: Figure 1 As shown. The method includes the following steps:

[0044] (1) The bismuth matte (Cu:25%, Fe:1.29%, S:8.92%, Pb:35.6%, Sb:13.1%, Ag:2.36%, Bi:2.7%, As:1.75%) lumps were crushed to a particle size of less than 200 mesh and used as raw material for bismuth matte leaching;

[0045] (2) Place an acidic solvent containing 5 g / L copper ions, 3 g / L bismuth ions, 1.5 g / L iron ions, 0.3 g / L antimony ions and 1.6 mol / L sulfuric acid into a 1 L beaker, add 100 g bismuth matte powder, the reaction temperature is 85 °C, the liquid-solid ratio is 10:1 (mL / g), first add 18 ml of hydrogen peroxide dropwise evenly over about 1 h, then stop adding hydrogen peroxide, and pass pure O2 into the bottom of the leaching solution at a flow rate of 0.3 L / min. The reaction time is 10 h. After leaching, filter and separate to obtain copper sulfate leaching solution and leaching residue. The leaching solution is used as raw material solution for electrowinning copper.

[0046] (3) Electrowinning was performed directly on the copper sulfate leaching solution at a current density of 300 A / m. 2 After 6 hours of electrolysis, the cathode copper was removed for analysis.

[0047] (4) The test results show that after leaching bismuth matte with acidic solvent, the copper leaching rate is 94%, the leaching rate of bismuth and antimony is close to 0, and the purity of the electrolytic copper obtained after electrowinning of copper sulfate leaching solution is 99.995%, which meets the national standard A grade electrolytic copper standard, and the current efficiency is 94.7%.

[0048] Example 2

[0049] This embodiment provides a method for recovering copper by acidic leaching of bismuth matte, the process flow of which is as follows: Figure 1 As shown. The method includes the following steps:

[0050] (1) The bismuth matte (Cu: 45.3%, Fe: 0.34%, S: 11.3%, Pb: 30.9%, Sb: 0.72%, Ag: 4.58%, Bi: 1.62%, As: 0.093%) lumps were crushed to a particle size of less than 200 mesh and used as raw material for bismuth matte leaching;

[0051] (2) Place an acidic solvent containing 25 g / L copper ions, 3 g / L bismuth ions, 1.5 g / L iron ions, 0.3 g / L antimony ions and 2.3 mol / L sulfuric acid into a 1 L beaker, add 100 g bismuth matte powder, the reaction temperature is 80℃, the liquid-solid ratio is 8:1 (mL / g), first add 45 ml hydrogen peroxide evenly dropwise over about 1 h, then stop adding hydrogen peroxide, and pass pure O2 into the bottom of the leaching solution at a flow rate of 0.5 L / min, the reaction time is 12 h, after leaching is completed, filter and separate to obtain copper sulfate leaching solution and leaching residue, the copper sulfate leaching solution is used as raw material solution for electrowinning copper;

[0052] (3) Electrowinning was performed directly on the copper sulfate leaching solution at a current density of 250 A / m. 2 After 7 hours of electrolysis, the cathode copper was removed for analysis.

[0053] (4) The test results show that after leaching bismuth matte with acidic solvent, the copper leaching rate is 94.5%, the leaching rate of bismuth and antimony is close to 0, and the purity of the electrolytic copper obtained after electrowinning of copper sulfate leaching solution is 99.993%, which meets the national standard A grade electrolytic copper standard, and the current efficiency is 94.2%.

[0054] Example 3

[0055] This embodiment provides a method for recovering copper by acidic leaching of bismuth matte, the process flow of which is as follows: Figure 1 As shown. The method includes the following steps:

[0056] (1) The bismuth matte (Cu: 49.3%, Fe: 2.67%, S: 12.2%, Pb: 12.7%, Sb: 4.0%, Ag: 2.83%, Bi: 1.82%, As: 1.3%) lumps were crushed to a particle size of less than 200 mesh and used as raw material for bismuth matte leaching;

[0057] (2) Place an acidic solvent containing 25 g / L copper ions, 3 g / L bismuth ions, 1.5 g / L iron ions, 0.3 g / L antimony ions and 2.3 mol / L sulfuric acid into a 1 L beaker, add 100 g bismuth matte powder, the reaction temperature is 80 °C, the liquid-solid ratio is 6:1 (mL / g), first add 45 ml hydrogen peroxide dropwise evenly over about 1 h, then stop adding hydrogen peroxide, and pass pure O2 into the bottom of the leaching solution at a flow rate of 1 L / min. The reaction time is 15 h. After leaching, filter and separate to obtain copper sulfate leaching solution and leaching residue. The copper sulfate leaching solution is used as a raw material solution for electrowinning copper.

[0058] (3) Electrowinning was performed directly on the copper sulfate leaching solution at a current density of 300 A / m. 2 After electrolysis for 5 hours, the cathode copper was removed for analysis.

[0059] (4) The test results show that after leaching bismuth matte with acidic solvent, the copper leaching rate is 93.5%, the leaching rate of bismuth and antimony is close to 0, and the purity of the electrolytic copper obtained after electrowinning of copper sulfate leaching solution is 99.993%, which meets the national standard A grade electrolytic copper standard, and the current efficiency is 93.8%.

[0060] This invention can efficiently leach and separate copper from bismuth matte and further enrich and recover elements such as gold, silver, lead, bismuth, and antimony, which has significant advantages in terms of environmental protection and resource recycling.

[0061] The above provides a detailed description of a fully wet process for recovering copper from bismuth matte according to embodiments of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of this application; furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

[0062] Certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The terms "comprising" and "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising / including but not limited to". "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error. The following descriptions in the specification are preferred embodiments for carrying out this application; however, these descriptions are for the purpose of illustrating the general principles of this application and are not intended to limit the scope of this application. The scope of protection of this application shall be determined by the appended claims.

[0063] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes said element.

[0064] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0065] The foregoing description illustrates and describes several preferred embodiments of this application. However, as previously stated, it should be understood that this application is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the application concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this application should be within the protection scope of the appended claims.

Claims

1. A process for the recovery of copper from bismuth copper matte by full wet process, characterized by, The process specifically comprises the following steps: S1) crushing and grinding bulk bismuth matte to a certain particle size to obtain bismuth matte powder; The particle size is more than 80% less than 200 mesh; S2) mixing the bismuth matte powder obtained in S1) with an acidic solvent in a certain proportion, continuously stirring at a certain rate, heating to a certain temperature, maintaining for a certain time, after leaching is completed, filtering to obtain leaching residue and copper-containing acidic leaching solution; The solid-liquid ratio of the bismuth matte and the acidic solvent is 1 kg: 6.0 L-10 L, the stirring speed is more than 100 r / min, an oxidizing agent is continuously added during the leaching process, the pressure is normal pressure, the reaction temperature is 70-95℃, and the holding time is 6-15 h; The sulfuric acid concentration in the acidic solvent is 1.6-2.3 mol / L, the copper ion concentration is 5-25 g / L, the bismuth ion concentration is 0.5-3 g / L, the iron ion concentration is 0-3 g / L, and the antimony ion concentration is 0-0.3 g / L; The oxidizing agent is H2O2 and oxygen; The amount of H2O2 added is 0.1-0.5 times the weight of the bismuth matte; oxygen is added at a flow rate of 1-10 L / min per kg of bismuth matte powder; S3) adding a certain amount of additive to the copper-containing acidic leaching solution obtained in S2) and directly electrodepositing under a suitable current density to obtain electrodeposited copper.

2. The process according to claim 1, characterized in that, The amount of additive added in S3) is 20-400 g / t of copper; the current density is controlled at 150 A / m 2 ~ 300 A / m 2 .

3. The process of claim 2, wherein, The additive is one or a combination of several of bone glue, gelatin, guar gum, casein, thiourea, polyethylene glycol, chloride ion, cobalt sulfate, and avicel.

4. The process of claim 1, wherein, The anode of the electrolytic cell in the electrodeposition process of S3) is a lead alloy plate, and the cathode is a stainless steel plate. The electrolytic waste liquid can be returned to the acidic solvent for recycling.

5. The process of claim 1, wherein, The copper leaching rate of the process is not less than 94%, the bismuth and antimony leaching rates are close to 0, and the purity of the electrodeposited copper obtained after electrodeposition of the copper sulfate leaching solution is 99.995%.

6. Electrowon copper characterized in that, The electrodeposited copper is prepared by the process of any one of claims 1-5.

Images