A method for separating and extracting lead and zinc from lead-zinc sulfide ore powder

Abstract

The application discloses a method for separating and extracting lead and zinc from lead-zinc sulfide ore powder, and belongs to the technical field of non-ferrous metal extraction. The method comprises the following steps: adding a surfactant and a dilute acid solution into the lead-zinc sulfide ore powder, pouring the mixture into a sealed reaction kettle after uniform mixing, opening stirring after oxygen heating to a constant temperature for oxygen pressure leaching, carrying out liquid-solid separation after reaching a predetermined time, obtaining lead sulfate base leaching residue and zinc-iron containing leaching solution, adding an oxidizing agent into the zinc-iron containing leaching solution, adding a neutralizing agent for neutralization and hydrolysis after reaction, obtaining a zinc solution after impurity removal, adding the lead sulfate base leaching residue into an alkaline desulfurization agent for desulfurization reaction, leaching in an acidic leaching agent to obtain a lead containing leaching solution, carrying out electrodeposition on the lead containing leaching solution to obtain metallic lead, and returning waste electrolyte to the acidic leaching agent to realize recycling of the leaching agent. The method for separating and extracting lead and zinc from lead-zinc sulfide ore powder realizes efficient and deep separation and recovery of zinc and lead in the lead-zinc sulfide ore.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of non-ferrous metal extraction, and particularly relates to a method for separating and extracting lead and zinc from lead-zinc sulfide ore powder. BACKGROUND

[0002] Lead-zinc sulfide ore is an important polymetallic mineral resource, in which galena (PbS) and sphalerite (ZnS) usually exist in the form of close symbiosis. At present, lead-zinc separation is mainly carried out by flotation in industry. According to the differences in the surface properties of minerals, flotation technology can be divided into processes such as preferential flotation, mixed flotation and floatable flotation. However, the existing flotation separation process generally has the following technical bottlenecks: (1) large amount of reagent consumption and strong toxicity; (2) complex process flow; (3) low concentrate yield; (4) high lead-zinc mutual content rate and other problems, which seriously restrict the efficient utilization of resources.

[0003] In terms of lead smelting, it is mainly divided into two categories: pyrometallurgical smelting and hydrometallurgical extraction. The traditional pyrometallurgical lead smelting adopts sintering roasting-air blast furnace reduction process, which has problems such as high energy consumption, low-concentration SO2 emission polluting the environment and the like. Modern lead metallurgical methods have been improved, such as bottom-blown molten bath smelting, flash smelting, top-blown submerged smelting and the like, but the smelting temperature still needs to be maintained at above 1100℃, and problems such as high energy consumption, lead vapor pollution and the like still exist. The hydrometallurgical lead extraction technology mainly includes FeCl3 oxidation method, galena-manganese ore leaching method and silicon-fluoride acid system oxidation leaching method. Among them, the FeCl3 oxidation method has technical difficulties such as easy volatilization of hydrochloric acid, serious equipment corrosion, difficulty in collecting high-temperature chlorine gas and the like; the silicon-fluoride acid system oxidation leaching method is unstable due to fluorides, and toxic hydrogen fluoride gas is easily decomposed, which leads to a poor operating environment and poses a threat to the health of production personnel.

[0004] The existing patent CN202410140673.0 discloses a processing technology of complex sulfide ore and carbonate ore symbiotic lead-zinc ore, which comprises the following steps: after the raw ore is ground, the sulfide ore is mixed and floated, the carbonate ore is floated, and self-oxidation pressure leaching, electrodeposition, ore separation and the like are carried out. The above patent first floats the lead-zinc sulfide ore into concentrate, and then uses self-oxidation pressure leaching treatment without adding acid, but uses the sulfur of the sulfide ore to generate sulfuric acid under the conditions of pressure and oxygen to extract the metal, which has the advantages of low acidity and low impurities in the leaching solution. However, in order to obtain high-grade lead ore required for smelting, the mixed lead-zinc ore needs to separate the sulfide ore and the carbonate ore through the flotation process in the above patent, and a plurality of flotation aids such as a foaming agent and a collector are added in the flotation process, which has the disadvantages of complex and long process flow, large amount of reagent, high reagent cost and the like. Therefore, it is necessary to innovate and upgrade the process, develop green and low-carbon, clean and efficient new technologies for separating and recovering co-associated elements of lead and zinc, and realize the maximization of resource utilization and the minimization of environmental pollution. SUMMARY

[0005] The application aims to provide a method for separating and extracting lead and zinc from lead-zinc sulfide ore powder, and to realize efficient and deep separation and recovery of zinc and lead in the lead-zinc sulfide ore.

[0006] To achieve the above-mentioned purpose, the application provides a method for separating and extracting lead and zinc from lead-zinc sulfide ore powder, comprising the following steps:

[0007] S1, a certain mass of lead-zinc sulfide ore powder is weighed, a surfactant and a dilute acid solution are added, and after being uniformly mixed, the mixture is poured into a sealed reaction kettle;

[0008] S2, oxygen is passed to heat to a constant temperature, and then stirring is started for pressure leaching, and after a predetermined time, liquid-solid separation is performed to obtain lead sulfate-based leaching residue containing pyrite and elemental sulfur and zinc-iron leaching solution;

[0009] S3, an oxidizing agent is added to the zinc-iron leaching solution, and after reaction, a neutralizing agent is added for neutralization and hydrolysis, and after impurity removal, a zinc solution is obtained;

[0010] S4, the lead sulfate-based leaching residue is added to an alkaline desulfurization agent for desulfurization reaction to generate lead carbonate-based conversion residue, and the lead carbonate-based conversion residue is leached in an acidic leaching agent to obtain a lead-containing leaching solution;

[0011] S5, the lead-containing leaching solution is subjected to electrodeposition to obtain metallic lead, and the waste electrolyte is returned to the acidic leaching agent to realize recycling of the leaching agent;

[0012] S6, the insoluble leaching residue is subjected to flotation treatment to obtain pyrite and elemental sulfur.

[0013] Preferably, in S1, the particle size of the lead-zinc sulfide ore powder is not greater than 75 μm; the surface additive is one or more of lignin, lignin sulfonate, alkyl benzene sulfonate, anthratine, lignite, and o-phenylenediamine, and the amount of the surface additive is 0.2% to 2.0% of the mass of the lead-zinc sulfide ore powder; and the dilute acid is sulfuric acid, nitric acid, or methyl sulfonic acid.

[0014] Preferably, in S2, during the pressure leaching process, H + The concentration is 0.2 mol / L to 4.0 mol / L, the temperature is 80°C to 150°C, the time is 60 min to 300 min, and the oxygen partial pressure is 0.4 MPa to 2.0 MPa.

[0015] Preferably, in S3, the oxidizing agent is hydrogen peroxide, oxygen, or ozone, the neutralizing agent is CaO, ZnO, Ca(OH)2, or Zn(OH)2, and the hydrolysis end point pH is 2.5 to 5.5.

[0016] Preferably, in the S4, the basic desulfurizer is one or more of Na2CO3, NaHCO3, (NH4)2CO3, NaOH, NH4HCO3 and ammonia water, and the liquid-solid ratio of the lead sulfate-based leaching residue to the basic desulfurizer is 3 mL / g-15 mL / g.

[0017] Preferably, in the S4, the desulfurization reaction temperature is 25℃, -95℃, and the desulfurization reaction time is 20 min-120 min.

[0018] Preferably, in the S4, the acid leaching agent is nitric acid, methyl sulfonic acid, HCl-NaCl or HCl-CaCl2 solution, and the liquid-solid ratio of the lead carbonate-based conversion residue to the acid leaching agent is 4 mL:10 g.

[0019] Preferably, in the S4, the acid leaching temperature is 25℃-85℃, and the time is 20 min-60 min, and the H + The molar ratio of Pb to H H+ is n Pb =1.0-3.5.

[0020] Preferably, in the S5, the cathode current density in the electrodeposition is 100 A / m 2 -300 A / m 2 , the electrolyte temperature is 25℃-65℃, and the pole distance is 3 cm-10 cm.

[0021] Preferably, in the S5, the electrodeposition anode plate is a graphite plate or a platinum-titanium anode, and the electrodeposition cathode plate is a lead anode sheet, a titanium plate or a stainless steel plate.

[0022] The method for separating and extracting lead and zinc from lead-zinc sulfide ore powder has the following advantages and positive effects:

[0023] 1. The present application can realize the phase conversion of galena into slag and the leaching of sphalerite into liquid by controlling the oxygen pressure leaching conditions, thereby creating good conditions for the subsequent recovery of lead and zinc.

[0024] 2. The present application reduces the intermediate links, avoids the complex multi-stage flotation process in the flotation method, and avoids the environmental pollution caused by flotation reagents such as collecting agents and foaming agents. This not only reduces the equipment investment cost, but also reduces the labor intensity of the operating personnel, improves the production efficiency, and has good comprehensive utilization effect of valuable elements. Not only does the present application realize the separation of lead, zinc and iron, but also prepares metal lead products and zinc-containing solution (zinc can be recovered subsequently). In addition, by controlling the oxygen pressure leaching conditions, part of the elemental sulfur in the sulfide ore is oxidized to elemental sulfur, and part of the elemental sulfur is over-oxidized to SO4 2- , and the elemental sulfur can be separated from the insoluble pyrite by flotation treatment.

[0025] 3、The present application adopts full wet process to recover lead and zinc respectively, which has the following advantages: ① Avoid the pollution of lead-containing flue gas and SO2 generated in the process of pyrometallurgical smelting; ② Good separation effect of lead and zinc, significantly improved metal recovery rate; ③ Reduced energy consumption. Compared with pyrometallurgical smelting which needs to maintain a high temperature of 1100℃ or above, the wet process greatly reduces energy consumption, in line with the development direction of green metallurgy.

[0026] The technical solutions of the present application will be further described in detail below by means of the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The process flow chart of the embodiment of the present application. DETAILED DESCRIPTION

[0028] In the present application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. If there is any inconsistency, the meaning as explained in the specification or derived from the content described in the specification shall prevail. In addition, the terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0029] The embodiments of the present application will be described in detail below with reference to the drawings.

[0030] As shown in the figure. A method for separating and extracting lead and zinc from lead-zinc sulfide ore powder, comprising the following steps: Figure 1

[0031] S1, weigh a certain mass of lead-zinc sulfide ore powder, add a surfactant and a dilute acid solution, mix uniformly, and then pour into a sealed reaction kettle for oxygen pressure leaching.

[0032] The particle size of the lead-zinc sulfide ore powder is not greater than 75μm.

[0033] The surface additive is one or more of lignin, lignin sulfonate, alkyl benzene sulfonate, anthracite, lignite, and o-phenylenediamine. The amount of surface additive is 0.2% to 2.0% of the mass of the lead-zinc sulfide ore powder.

[0034] The dilute acid is sulfuric acid, nitric acid or methyl sulfonic acid.

[0035] S2, after oxygen is passed and the temperature is raised to a constant temperature, stirring is started, and after a predetermined time, liquid-solid separation is performed to obtain lead sulfate-based leaching residue and zinc-iron-containing leaching solution.

[0036] During the oxygen pressure leaching process, the H + concentration is 0.2mol / L-4.0mol / L.

[0037] ​The temperature was 80℃-150℃, the time was 60min-300min, and the oxygen partial pressure was 0.4MPa-2.0MPa.

[0038] S3. Add an oxidizing agent to the zinc-iron leaching solution, and after the reaction, add a neutralizing agent to neutralize and hydrolyze the solution. After removing impurities, a zinc solution is obtained.

[0039] The oxidant is hydrogen peroxide, oxygen, or ozone.

[0040] The neutralizing agent is CaO, ZnO, Ca(OH)2 or Zn(OH)2, and the pH at the hydrolysis endpoint is 2.5-5.5.

[0041] S4. Add lead sulfate-based leaching residue to alkaline desulfurizing agent for desulfurization reaction to generate lead carbonate-based conversion residue. Leach the lead carbonate-based conversion residue in acidic leaching agent to obtain lead-containing leachate.

[0042] The alkaline desulfurizing agent is one or more of Na2CO3, NaHCO3, (NH4)2CO3, NaOH, NH4HCO3, and ammonia water. The liquid-to-solid ratio of the lead sulfate-based leaching residue to the alkaline desulfurizing agent is 3 mL / g-15 mL / g.

[0043] The desulfurization reaction temperature is 25℃ and -95℃, and the desulfurization reaction time is 20min-120min.

[0044] The acidic leaching agent is nitric acid, methanesulfonic acid, HCl-NaCl or HCl-CaCl2 solution, and the liquid-to-solid ratio of lead carbonate-based conversion residue to acidic leaching agent is 4 mL: 10 g.

[0045] The acid leaching temperature is 25℃-85℃, and the time is 20min-60min. During the acid leaching process, the H₂O content is controlled. + The molar ratio of Pb to n H+ :n Pb =1.0-3.5.

[0046] S5. Electrodeposition is performed on the lead-containing leaching solution to obtain metallic lead. The waste electrolyte is returned to the acidic leaching agent to achieve the recycling of the leaching agent.

[0047] The cathode current density in electrodeposition is 100 A / m 2 -300 A / m 2 The electrolyte temperature is 25℃-65℃, and the electrode distance is 3cm-10cm.

[0048] The electrodeposition anode plate uses a graphite plate or a platinum-titanium anode, while the electrodeposition cathode plate uses a lead starting sheet, a titanium plate, or a stainless steel plate.

[0049] In the pressurized oxygen leaching process, by controlling the oxygen pressure leaching conditions, ZnS is converted into ZnSO4 into the leaching solution, and part of the pyrite is dissolved into the leaching solution, and then the impurities can be removed by oxidation, neutralization and hydrolysis, and then recovered simply, and PbS phase is converted into PbSO4 form and remains in the leaching residue, so that the separation of lead and zinc is realized. Elemental sulfur in the sulfide ore is oxidized into elemental sulfur, and part of the elemental sulfur is over-oxidized into SO4 2- , combined with Pb 2+ in the solution into PbSO4. The lead sulfate (Ksp[PbSO4] = 1.6 x 10 -8 ) base leaching residue containing pyrite and elemental sulfur obtained in the oxygen pressure leaching stage can convert PbSO4 into easily acid-soluble lead carbonate (Ksp[PbCO3] = 3.3 x 10 -14 ) in the alkaline desulfurization liquid, and then can be dissolved in the acid leaching agent, and the metal lead can be precipitated by the electrodeposition method. The insoluble pyrite and elemental sulfur can be separated by flotation to obtain pyrite and elemental sulfur.

[0050] The main chemical reactions occurring in the present application are as follows:

[0051] Oxygen pressure leaching process:

[0052] 2FeS2+O2+4H + =2Fe 2+ +4S 0 +2H2O

[0053] PbS+8Fe 3+ +4H2O=PbSO4+8Fe 2+ +8H +

[0054] ZnS+2Fe 3+ =Zn 2+ +S 0 +2Fe 2+

[0055] 2S 0 +3O2+2H2O=2SO4 2- +4H +

[0056] Desulfurization conversion process:

[0057] PbSO4+Na2CO3=PbCO3+Na2SO4

[0058] The technical solutions of the present application are further described below by examples.

[0059] Example 1

[0060] A method for separating and extracting lead and zinc from a lead-zinc sulfide ore powder, comprising the following steps:

[0061] S1, taking lead-zinc sulfide powder as raw material, grinding it to less than 75 μm. A certain mass of lead-zinc sulfide powder is weighed, mixed with calcium lignosulfonate (mass ratio 0.7%) and 1 mol / L dilute sulfuric acid to form a slurry, and then poured into a sealed reaction kettle.

[0062] S2, adjust the oxygen partial pressure in the sealed reaction kettle to 0.4 MPa, heat to 150°C, then open the stirring and react for 180 min, and then separate the liquid and solid while hot to obtain lead sulfate-based leaching residue and zinc-iron-containing leaching solution.

[0063] S3, hydrogen peroxide is added to the zinc-iron-containing leaching solution, fully reacted, then calcium oxide emulsion is added to neutralize to pH=3.5 to remove impurities, and then filtered to obtain a zinc solution.

[0064] S4, the lead sulfate-based leaching residue is subjected to desulfurization reaction in NaHCO3 solution to form lead carbonate-based conversion residue, and then n H+ :n Pb =3.2 methyl sulfonic acid leaching agent is added, and the reaction is carried out at a temperature of 50°C and a liquid-solid ratio of 8 mL / g for 60 min.

[0065] S5, the lead-containing leaching solution obtained by filtering in the above process is subjected to electrodeposition at a cathode current density of 220 A / m 2 and 40°C to obtain metallic lead, and the waste electrolyte is returned to the leaching process to realize the recycling of the leaching agent.

[0066] In this embodiment, the zinc leaching rate is 94.76%, the lead direct recovery rate is 96.54%, and the purity of metallic lead is 99.99%.

[0067] Example 2

[0068] A method for separating and extracting lead and zinc from lead-zinc sulfide powder, comprising the following steps:

[0069] S1, taking lead-zinc sulfide powder as raw material, grinding it to less than 75 μm. A certain mass of lead-zinc sulfide powder is weighed, mixed with sodium lignosulfonate (mass ratio 0.5%) and 1.5 mol / L methyl sulfonic acid to form a slurry, and then poured into a sealed reaction kettle.

[0070] S2, adjust the oxygen partial pressure in the sealed reaction kettle to 0.8 MPa, heat to 150°C, then open the stirring and react for 180 min, and then separate the liquid and solid while hot to obtain lead sulfate-based leaching residue and zinc-iron-containing leaching solution.

[0071] S3, hydrogen peroxide is added to the zinc-iron-containing leaching solution, fully reacted, then calcium oxide emulsion is added to neutralize to pH=3 to remove impurities, and then filtered to obtain a zinc solution.

[0072] S4, the lead sulfate-based leaching residue is subjected to desulfurization reaction in Na2CO3 solution to generate lead carbonate-based conversion residue, and then n H+ :n Pb = 3.0, a methyl sulfonic acid leaching agent is added, and reaction is carried out at a temperature of 60°C and a liquid-solid ratio of 10 mL / g for 60 min.

[0073] S5, the lead-containing leaching solution obtained through filtration in the above process is subjected to electrodeposition at a cathode current density of 200 A / m 2 and 50°C to obtain metal lead, and the waste electrolyte is returned to the leaching process to realize recycling of the leaching agent.

[0074] In this embodiment, the zinc leaching rate is 93.28%, the lead direct recovery rate is 96.78%, and the purity of the metal lead is 99.99%.

[0075] Example 3

[0076] A method for separating and extracting lead and zinc from lead-zinc sulfide ore powder, comprising the following steps:

[0077] S1, taking lead-zinc sulfide ore powder as raw material, grinding it to less than 75 μm. A certain amount of lead-zinc sulfide ore powder is weighed, mixed with calcium lignin sulfonate (mass ratio 0.6%) and 0.8 mol / L dilute sulfuric acid to form a slurry, and then poured into a sealed reaction kettle.

[0078] S2, adjust the oxygen partial pressure in the sealed reaction kettle to 1.0 MPa, and after heating to 180°C, start stirring and react for 120 min. After hot liquid-solid separation, lead sulfate-based leaching residue and zinc-iron-containing leaching solution are obtained.

[0079] S3, zinc-iron-containing leaching solution is added with hydrogen peroxide, fully reacted, and then calcium oxide emulsion is added for neutralization to pH = 4 to remove impurities, and then filtered to obtain zinc solution.

[0080] S4, the lead sulfate-based leaching residue is subjected to desulfurization reaction in (NH4)2CO3 solution to generate lead carbonate-based conversion residue, and then n H+ :n Pb = 2.8, a methyl sulfonic acid leaching agent is added, and reaction is carried out at a temperature of 80°C and a liquid-solid ratio of 9 mL / g for 60 min.

[0081] S5, the lead-containing leaching solution obtained through filtration in the above process is subjected to electrodeposition at a cathode current density of 200 A / m 2 and 50°C to obtain metal lead, and the waste electrolyte is returned to the leaching process to realize recycling of the leaching agent.

[0082] In this embodiment, the zinc leaching rate is 93%, the lead direct recovery rate is 96%, and the purity of the metal lead is 99.99%.

[0083] Therefore, the method for separating and extracting lead and zinc from lead-zinc sulfide ore powder achieves efficient and deep separation and recovery of zinc and lead in the lead-zinc sulfide ore.

[0084] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit them. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can still be modified or replaced by equivalents, and these modifications or replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. A method for separating and extracting lead and zinc from a lead sulfide zinc ore powder, characterized by, The method comprises the following steps: S1, a certain mass of lead-zinc sulfide ore powder is weighed, a surfactant and a dilute acid solution are added, and the mixture is uniformly mixed and then poured into a sealed reaction kettle; S2, oxygen is passed to heat to a constant temperature, stirring is started, and then oxygen pressure leaching is carried out; after a predetermined time, liquid-solid separation is carried out, and a lead sulfate-based leaching residue containing pyrite and elemental sulfur and a zinc-iron-containing leaching solution are obtained; S3, an oxidizing agent is added to the zinc-iron-containing leaching solution, a neutralizing agent is added after reaction for neutralization and hydrolysis, and a zinc solution is obtained after impurity removal; S4, the lead sulfate-based leaching residue is added to an alkaline desulfurization agent for desulfurization reaction to generate a lead carbonate-based conversion residue, and the lead carbonate-based conversion residue is leached in an acidic leaching agent to obtain a lead-containing leaching solution; S5, the lead-containing leaching solution is subjected to electrodeposition to obtain metallic lead, and the waste electrolyte is returned to the acidic leaching agent to realize recycling of the leaching agent; S6, the insoluble leaching residue is subjected to flotation treatment to obtain pyrite and elemental sulfur. In S1, the particle size of the lead-zinc sulfide ore powder is not greater than 75 μm; the surface additive is one or more of lignin, lignin sulfonate, alkyl benzene sulfonate, anthracite, lignite, and o-phenylenediamine, and the amount of the surface additive is 0.2% to 2.0% of the mass of the lead-zinc sulfide ore powder; The dilute acid is methyl sulfonic acid; In the S2, the H + The concentration was 1.5 mol / L, the temperature was 150°C, the time was 180 min, and the oxygen partial pressure was 0.8 MPa.

2. A process for the separation and extraction of lead and zinc from lead zinc sulphide ore fines as claimed in claim 1 wherein: In S3, the oxidizing agent is hydrogen peroxide, oxygen, or ozone, the neutralizing agent is CaO, ZnO, Ca(OH)2, or Zn(OH)2, and the hydrolysis end point pH is 2.5-5.

5.

3. A process for the separation and extraction of lead and zinc from lead zinc sulphide ore fines as claimed in claim 1 wherein: In S4, the alkaline desulfurization agent is one or more of Na2CO3, NaHCO3, (NH4)2CO3, NaOH, NH4HCO3, and ammonia water, and the liquid-solid ratio of the lead sulfate-based leaching residue to the alkaline desulfurization agent is 3 mL / g-15 mL / g.

4. A process for separation and extraction of lead and zinc from lead zinc sulphide ore powder as claimed in claim 1, wherein: In S4, the desulfurization reaction temperature is 25 °C-95 °C, and the desulfurization reaction time is 20 min-120 min.

5. The method for separating and extracting lead and zinc from lead-zinc sulfide ore powder according to claim 1, characterized in that: In S4, the acidic leaching agent is nitric acid, methyl sulfonic acid, an HCl-NaCl or HCl-CaCl2 solution, and the liquid-solid ratio of the lead carbonate-based conversion residue to the acidic leaching agent is 4 mL / g-10 mL / g.

6. The method for separating and extracting lead and zinc from lead-zinc sulfide ore powder according to claim 1, characterized in that: In the S4, the temperature of the acid leaching is 25 °C-85 °C, the time is 20 min-60 min, and the H + The molar ratio to Pb is n H+ : n Pb =1.0-3.

5.

7. The method for separating and extracting lead and zinc from lead-zinc sulfide ore powder according to claim 1, characterized in that: In the S5, the cathode current density in the electrodeposition is 100 A / m 2 -300 A / m 2 , the electrolyte temperature is 25 °C-65 °C, and the pole distance is 3 cm-10 cm.

8. The method for separating and extracting lead and zinc from lead-zinc sulfide ore powder according to claim 1, characterized in that: In S5, the electrodeposition anode plate is a graphite plate or a platinum-titanium anode, and the electrodeposition cathode plate is a lead anode plate, a titanium plate, or a stainless steel plate.

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