Anode passivation inhibitor and electrolysis method for low-arsenic copper anode electrolytic refining

Abstract

The present invention belongs to the field of copper electrolytic refining, and relates to a kind of anode passivation inhibitor and method for low-arsenic copper anode electrolytic refining. The method first loads the anode plate and stainless steel cathode plate after soaking and washing into an electrolytic cell, and then adds an electrolyte containing copper ions; and the temperature and circulation amount of the electrolyte containing copper ions are adjusted; Then the anode passivation inhibitor of the low-arsenic copper anode electrolytic refining is added uniformly and continuously into a circulation tank, a rectifier is started, the anode passivation inhibitor is introduced into the electrolyte containing copper ions, current density is controlled, and low-arsenic copper anode electrolytic refining is completed. The method of the present invention utilizes an inhibitor to generate hydrogen ions in situ after the dissolution of the electrolyte, dissolves the passivation layer, significantly improves the anode passivation phenomenon in the copper electrolysis process, makes the anode passivated from the original only 4 6 days, becomes not passivated in the whole electrolysis cycle (20 22 days), with simple operation, low cost, improves production efficiency, and enhances the characteristics of raw material adaptability.

Description

Technical Field

[0001] The invention belongs to the field of copper electrolytic refining and relates to an anode passivation inhibitor for low-arsenic copper anode electrolytic refining and an electrolysis method. Background Art

[0002] During copper electrorefining, to improve production efficiency, the current density must be continuously increased. As the current density increases, the polarization potential of the anode increases. When this increases to a certain level, the electrochemical dissolution rate of the copper anode plate suddenly decreases, or even ceases to dissolve. This phenomenon, in which the copper anode ceases to electrochemically dissolve during the electrorefining process, is known as anode passivation. With the increasing complexity of material sources, low-arsenic copper anodes are being used in copper electrorefining. However, these anodes are highly susceptible to anode passivation under existing electrorefining process conditions.

[0003] Anode passivation is a serious threat to copper electrorefining. It causes a sharp increase in the cell voltage during production, significantly increasing DC power consumption and raising production costs. A decrease in copper ion concentration near the cathode causes impurities to precipitate along with copper on the cathode surface, degrading cathode quality. Severe anode passivation can even prevent normal electrorefining operations. Summary of the Invention

[0004] The present invention discloses an anode passivation inhibitor and an electrolysis method for low-arsenic copper anode electrolytic refining, so as to solve any of the above and other potential problems in the prior art.

[0005] To achieve the above object, the technical solution of the present invention is: an anode passivation inhibitor for low-arsenic copper anode electrolytic refining, the anode passivation inhibitor comprises gelatin, thiourea, hydrochloric acid and a hydroxyl-containing compound, and the mass ratio of each component is: 3-15:5-12:20-40:3-60.

[0006] Furthermore, the hydroxyl-containing compound is one or more of polyethylene glycol, polyvinyl alcohol, polyacrylic acid, methanol, ethanol, glycerol, glucose, salicylic acid, and ascorbic acid.

[0007] Another object of the present invention is to provide an electrolysis method for the above-mentioned anode passivation inhibitor for low-arsenic copper anode electrorefining, which method specifically comprises the following steps:

[0008] S1) firstly put the washed anode plate and the stainless steel cathode plate into an electrolytic cell, and then add an electrolyte containing copper ions;

[0009] S2) and adjusting the temperature and circulation amount of the electrolyte containing copper ions;

[0010] S3) adding the anode passivation inhibitor uniformly and continuously into the circulation tank, starting the rectifier, introducing the anode passivation inhibitor into the electrolyte containing copper ions, controlling the current density, and completing the low-arsenic copper anode electrolytic refining.

[0011] Furthermore, the electrolyte circulation rate in said S1) is 25-40 L / min, and the temperature is controlled at 55-70°C.

[0012] Furthermore, the copper ion concentration in the copper ion-containing electrolyte in S1) is 35-55 g / L, and the sulfuric acid concentration is 155-200 g / L.

[0013] Further, the current density in S2) is 270-330A / m 2 .

[0014] Furthermore, the cathode in S1) is 316L stainless steel.

[0015] Furthermore, the service life of the anode in the method is extended by at least 4 times.

[0016] The beneficial effects of the present invention are as follows: the method of the present invention utilizes an inhibitor to generate hydrogen ions in situ after dissolution of the electrolyte, dissolves the passivation layer, and significantly improves the anode passivation phenomenon during the copper electrolysis process, so that the anode is passivated in only 4 to 6 days instead of being passivated in the entire electrolysis cycle (20 to 22 days). The method has the characteristics of simple operation, low cost, improved production efficiency, and enhanced raw material adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a flow chart of an electrolytic method using an anode passivation inhibitor for electrolytic refining of low-arsenic copper anodes.

[0018] Figure 2 This is a photograph of the anode and cathode surfaces of an embodiment of the method of the present invention. DETAILED DESCRIPTION

[0019] The technical solution of the present invention is further described below with reference to specific embodiments.

[0020] The invention discloses an anode passivation inhibitor for low-arsenic copper anode electrolytic refining. The anode passivation inhibitor comprises gelatin, thiourea, hydrochloric acid and a hydroxyl-containing compound, and the mass ratio of the components is 3-15:5-12:20-40:3-60.

[0021] The hydroxyl-containing compound is one or more of polyethylene glycol, polyvinyl alcohol, polyacrylic acid, methanol, ethanol, glycerol, glucose, salicylic acid, and ascorbic acid.

[0022] like Figure 1As shown, the present invention provides an electrolysis method for an anode passivation inhibitor for low-arsenic copper anode electrolytic refining, the method specifically comprising the following steps:

[0023] S1) firstly put the washed anode plate and the stainless steel cathode plate into an electrolytic cell, and then add an electrolyte containing copper ions;

[0024] S2) and adjusting the temperature and circulation amount of the electrolyte containing copper ions;

[0025] S3) adding the anode passivation inhibitor uniformly and continuously into the circulation tank, starting the rectifier, introducing the anode passivation inhibitor into the electrolyte containing copper ions, controlling the current density, and completing the low-arsenic copper anode electrolytic refining.

[0026] The electrolyte circulation rate in said S1) is 25-40 L / min, and the temperature is controlled at 55-70°C.

[0027] The copper ion concentration in the copper ion-containing electrolyte in S1) is 35-55 g / L, and the sulfuric acid concentration is 155-200 g / L.

[0028] The amount of inhibitor added in S2) is as follows: maintaining the concentration of bone glue in the electrolyte at 30-150 g / t·Cu, the concentration of thiourea at 50-120 g / t·Cu, the concentration of hydrochloric acid at 200-400 g / t·Cu, and the concentration of the hydroxyl compound additive at 30-600 g / t·Cu.

[0029] The current density in S2) is 270-330A / m 2 .

[0030] The cathode in S1) is 316L stainless steel.

[0031] The service life of the anode in the method is extended by at least 4 times.

[0032] Example 1: The washed anode plate (anode composition is shown in Table 1) and a 316L permanent stainless steel cathode plate were placed in an electrolytic cell, and an electrolyte with a copper ion concentration of 45 g / L and a sulfuric acid concentration of 170 g / L was introduced. The electrolyte circulation rate was controlled at 30 L / min and the temperature was controlled at 65°C.

[0033] The anode passivation inhibitor was added uniformly and continuously into the circulation tank according to the electrolyte containing 100g / t·Cu of bone glue, 80g / t·Cu of thiourea, 27g / t·Cu of hydrochloric acid, glycerol and 290g / t·Cu of polyethylene glycol. After the temperature and circulation were stable, the rectifier was started and the current density was maintained at 300A / m 2 .

[0034] After 20 days of electrolysis, the cathode and anode plates were lifted and cleaned, and their surface quality was observed. Figure 2 As shown, from Figure 2 It can be seen that under the electrolysis conditions, no obvious passivation occurs at the anode.

[0035] Table 1: Anode composition

[0036]

[0037] Example 2: The washed anode plate (anode composition is shown in Table 1) and a 316L permanent stainless steel cathode plate were placed in an electrolytic cell, and an electrolyte with a copper ion concentration of 35 g / L and a sulfuric acid concentration of 155 g / L was introduced. The electrolyte circulation rate was controlled at 30 L / min and the temperature was controlled at 65°C.

[0038] The anode passivation inhibitor was added uniformly and continuously into the circulation tank according to the electrolyte containing 100g / t·Cu of bone glue, 80g / t·Cu of thiourea, 27g / t·Cu of hydrochloric acid, and 120g / t·Cu of ascorbic acid. After the temperature and circulation were stable, the rectifier was started and the current density was maintained at 330A / m 2 .

[0039] After 20 days of electrolysis, the cathode and anode plates were lifted and cleaned, and their surface quality was observed. Figure 2 As shown, from Figure 2 It can be seen that under the electrolysis conditions, no obvious passivation occurs at the anode.

[0040] Example 3: The washed anode plate (anode composition is shown in Table 1) and a 316L permanent stainless steel cathode plate were placed in an electrolytic cell, and an electrolyte with a copper ion concentration of 55 g / L and a sulfuric acid concentration of 200 g / L was introduced. The electrolyte circulation rate was controlled at 30 L / min and the temperature was controlled at 65°C.

[0041] The anode passivation inhibitor was added to the circulation tank evenly and continuously according to the electrolyte containing 100g / t·Cu of bone glue, 80g / t·Cu of thiourea, 27g / t·Cu of hydrochloric acid, and 400g / t·Cu of methanol. After the temperature and circulation were stable, the rectifier was started and the current density was maintained at 270A / m 2 .

[0042] After 20 days of electrolysis, the cathode and anode plates were lifted and cleaned, and their surface quality was observed. Figure 2 As shown, from Figure 2 It can be seen that under the electrolysis conditions, no obvious passivation occurs at the anode.

[0043] The above describes in detail the anode passivation inhibitor and electrolysis method for low-arsenic copper anode electrolytic refining provided in the embodiments of the present application. The above embodiments are intended only to facilitate understanding of the method and core concept of the present application. Furthermore, those skilled in the art will appreciate that variations in the specific implementation and scope of application are possible based on the concepts of the present application. Therefore, the contents of this specification should not be construed as limiting the present application.

[0044] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different nouns to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" and "comprising" mentioned throughout the specification and claims are open-ended terms, so they should be interpreted as "including / including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problems within a certain error range and basically achieve the technical effects. The subsequent description in the specification is a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application, and is not used to limit the scope of the present application. The scope of protection of the present application shall be as defined in the attached claims.

[0045] It should also be noted that the terms "include," "comprises," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such product or system. In the absence of further limitations, an element defined by the phrase "comprises a..." does not exclude the presence of other identical elements in the product or system comprising the element.

[0046] It should be understood that the term "and / or" as used herein is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0047] The above description shows and describes several preferred embodiments of the present application. However, as previously mentioned, it should be understood that the present application is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Instead, the present application can be used in various other combinations, modifications, and environments and can be modified within the scope of the application concept described herein through the above teachings or technology or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present application should be protected by the claims appended hereto.

Claims

1. An electrolytic method for low-arsenic copper anodic electrorefining using an anodic passivation inhibitor, characterized in that: The method specifically comprises the following steps: S1) First, the washed anode plate and the stainless steel cathode plate are placed in the electrolytic cell, and then the electrolyte containing copper ions is added; The Cu content in the anode plate is 99.4%, and the As content is 50 ppm; The copper ion concentration in the copper ion-containing electrolyte is 35-55 g / L, and the sulfuric acid concentration is 155-200 g / L; S2) and adjusting the temperature and circulation amount of the electrolyte containing copper ions; The electrolyte circulation rate is 25-40 L / min and the temperature is controlled at 55-70℃; S3) adding the anode passivation inhibitor uniformly and continuously into the circulation tank, starting the rectifier, introducing the anode passivation inhibitor into the electrolyte containing copper ions, controlling the current density, and completing the low-arsenic copper anode electrolytic refining; The anode passivation inhibitor comprises bone glue, thiourea, hydrochloric acid and a hydroxyl-containing compound, and the mass ratio of each component is: 3-15: 5-12: 20-40: 3-60; Current density is 270-330 A / m 2 ; The amount of inhibitor added is: maintaining the concentration of bone glue in the electrolyte at 100 g / t•Cu, the concentration of thiourea at 80 g / t•Cu, the concentration of hydrochloric acid at 27 g / t•Cu, and the concentration of glycerol and polyethylene glycol at 290 g / t•Cu. The electrolyte contains 100g / t·Cu of bone glue, 80g / t·Cu of thiourea, 27g / t·Cu of hydrochloric acid, 120g / t·Cu of ascorbic acid or Bone glue 100g / t·Cu, thiourea 80g / t·Cu, hydrochloric acid 27g / t·Cu, methanol 400g / t·Cu.

2. The electrolysis method according to claim 1, characterized in that The stainless steel cathode plate in S1) is a 316L stainless steel cathode.

3. The electrolysis method according to claim 1, wherein The service life of the anode in the method is extended by at least 4 times.

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