Preparation method and application of high-energy-efficiency titanium-based lead dioxide anode

Abstract

The invention belongs to the technical field of electrochemical anode preparation, and particularly relates to a preparation method and application of a high-energy-efficiency titanium-based lead dioxide anode, and the preparation method comprises the following steps: pretreating a titanium plate, preparing a tin-antimony solution, coating and sintering the titanium plate to prepare a tin-antimony oxide intermediate layer, and electrodepositing and plating lead to obtain the high-energy-efficiency titanium-based lead dioxide anode. According to the method, the electrochemical performance and catalytic activity of the titanium-based lead dioxide anode can be improved, and the zinc electrodeposition power consumption of the titanium-based lead dioxide anode is reduced when the method is applied to the field of zinc electrodeposition.

Description

Technical Field

[0001] The invention belongs to the technical field of electrochemical anode preparation, and specifically relates to a preparation method and application of a high-energy-efficiency titanium-based lead dioxide anode. Background Art

[0002] Hydrometallurgy consists of five processes: roasting, leaching, purification, electrolytic deposition, and casting. The power consumption of zinc electrolytic deposition accounts for more than 70% of the total power consumption of hydrometallurgy. The theoretical power consumption of zinc electrolytic deposition is 1500kWh / t, and the actual power consumption is much higher than the theoretical power consumption. For example, the power consumption of domestic zinc electrolytic plants is generally 3000-3500kWh / t, which is higher than the foreign industry level of 2800-3100kWh / t. Therefore, in order to improve energy efficiency, the top priority for zinc electrolytic plants to achieve energy saving and consumption reduction and improve economic benefits is to reduce the power consumption of electrolytic deposition. As one of the core materials of zinc electrolytic deposition, the performance of anode deeply affects the economic benefits of zinc electrolytic deposition.

[0003] As a new type of insoluble anode for hydrometallurgy, titanium-based lead dioxide anode has the advantages of long life, deformation resistance, and corrosion resistance. The purity of the produced cathode zinc can reach 99.995%, but its cell voltage is relatively high, resulting in high DC power consumption for zinc electrolysis. Therefore, how to improve the electrochemical performance and catalytic activity of titanium-based lead dioxide anode to reduce the power consumption of zinc electrolysis is an important development direction of titanium-based lead dioxide anode.

[0004] The existing Chinese invention patent with announcement number CN201610964813 proposes a titanium-based PbO 2 -PANI shape-stable anode preparation method and use, the method in titanium-based PbO 2 Preparation of a layer of PbO on the anode surface 2 -PANI composite surface layer for degradation of organic wastewater.

[0005] The above method has the following disadvantages when used in hydrometallurgy: a layer of PbO must be prepared in advance. 2 , and then prepare a layer of PbO 2 -PANI composite surface layer has complicated preparation steps and high energy consumption. When operating in a hydrometallurgical strong acid system, the oxygen evolution potential is high, resulting in increased energy consumption. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a method for preparing a high-energy-efficiency titanium-based lead dioxide anode and its application, which can improve the electrochemical performance and catalytic activity of the titanium-based lead dioxide anode, and reduce the zinc electrolytic power consumption of the titanium-based lead dioxide anode in the application of zinc electrolytic deposition.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for preparing a high-energy-efficiency titanium-based lead dioxide anode comprises the following steps:

[0009] 1) Titanium plate pretreatment: sandblasting, pickling, rust removal and oil removal;

[0010] 2) preparing a tin-antimony solution: dissolving a tin salt and an antimony salt in a mixed solvent to prepare a tin-antimony solution; the mixed solvent is prepared from ethanol, ethylene glycol, concentrated hydrochloric acid and deionized water;

[0011] 3) brushing and sintering the tin-antimony solution prepared in step 2) on the titanium plate pretreated in step 1) multiple times to prepare a tin-antimony oxide intermediate layer;

[0012] 4) Preparation of electroplating solution: adding quaternary ammonium fluoride, cobalt nitrate and bismuth nitrate to the lead nitrate system electroplating solution, and then adding conductive polyaniline for ultrasonic treatment;

[0013] 5) The titanium plate with the tin-antimony oxide intermediate layer prepared in step 3) is used as the anode, and the titanium mesh is used as the insoluble cathode, and co-deposited in the electroplating solution prepared in step 4) to prepare a multi-component composite active layer to obtain a high-efficiency titanium-based lead dioxide anode.

[0014] Preferably, in step 1), the titanium plate is pickled, rusted and degreased simultaneously; the specific operation is: immerse the titanium plate in an environmentally friendly titanium oxide scale cleaning agent at 25 to 60° C. for 5 to 20 minutes, and then rinse it with pure water after taking it out.

[0015] Preferably, the volume proportion of deionized water in the mixed solvent in step 2) is 5-15%.

[0016] Preferably, the molar ratio of tin antimony ions in the tin antimony solution in step 2) is 15:1.

[0017] Preferably, the conductive polyaniline in step 4) is doped with dodecylbenzene sulfonic acid to be conductive, and has a molecular weight of 20,000 to 60,000; the conductive polyaniline is added to a lead nitrate system electroplating solution and ultrasonically dispersed for 10 to 60 minutes, stirred at 40 to 60° C. for 10 to 30 minutes, and the added amount is 0.1 to 1 g / L.

[0018] Preferably, in step 4), the addition amounts of the quaternary ammonium fluoride salt, cobalt nitrate, and bismuth nitrate are 0.2-0.5 g / L, 0.2-0.8 g / L, and 0.2-0.6 g / L, respectively.

[0019] Preferably, the concentration of lead nitrate in the lead nitrate system electroplating solution in step 4) is 180-240 g / L, and the pH value is 1-2.

[0020] Preferably, the co-deposition conditions for preparing the multi-component composite active layer in step 4) are: the current density is 10-40 mA / cm2 , temperature is 40-70℃, time is 1-3h.

[0021] The invention discloses an application of a high energy efficiency titanium-based lead dioxide anode in the field of zinc electrowinning.

[0022] Preferably, the specific operation process of the electrolytic zinc deposition is: using 125g / L ZnSO 4 and 180 g / L H2SO 4 The solution is the electrolyte, and an electrolytic cell with two cathodes and one anode is used. High-efficiency titanium-based lead dioxide is used as the anode, and the aluminum plate is used as the cathode. The distance between the anode and cathode is 3 cm, and the current density is 52 mA / cm 2 , electrochemical deposition was carried out at 40 °C.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The present invention uses ethanol, ethylene glycol, concentrated hydrochloric acid and a small amount of deionized water as a mixed solvent to prepare a tin-antimony solution. The obtained solution has a high flash point and low cost, and is suitable for industrial application. The tin-antimony oxide prepared from the above tin-antimony solution has fewer cracks in the middle layer, which can effectively prevent the diffusion of new ecological oxygen to the titanium substrate and reduce the oxygen evolution potential.

[0025] (2) The present invention uses quaternary ammonium fluoride, cobalt nitrate and bismuth nitrate to dope and modify PbO 2 Active layer, while using conductive polyaniline as an additive to change the morphology of the active layer, reduce particle size, reduce internal stress, increase specific surface area, and significantly improve the electrochemical performance, catalytic activity and life of the active layer;

[0026] (3) The high-efficiency titanium-based lead dioxide anode provided by the present invention has an electrolytic zinc current efficiency of up to 97%, which is comparable to that of conventional Ti / Sb-SnO 2 / PbO 2 Compared with direct current, the anode power consumption is reduced by 150kWh / t, which improves the energy efficiency of titanium-based lead dioxide anode zinc electroplating. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figures are scanning electron microscope images of the high-efficiency titanium-based lead dioxide anode prepared in Example 1; wherein, (a) is a scanning electron microscope image after 5 minutes of electrodeposition (×1000 times), (b) is a scanning electron microscope image after 5 minutes of electrodeposition (×5000 times), (c) is a scanning electron microscope image after 1 hour of electrodeposition (×1000 times), and (d) is a scanning electron microscope image after 1 hour of electrodeposition (×5000 times).

[0028] Figure 2 This is a linear sweep voltammetry curve of the high energy efficiency titanium-based lead dioxide anode prepared in Example 1.

[0029] Figure 3 This is the electrochemical impedance spectrum of the high-efficiency titanium-based lead dioxide anode prepared in Example 1.

[0030] Figure 4 This is a diagram of the enhanced life of the high-efficiency titanium-based lead dioxide anode prepared in Example 1.

[0031] Figure 5 This is a comparison chart of the current efficiency of the high-efficiency titanium-based lead dioxide anode prepared in Example 1 and the simulated zinc electrolysis of the comparative example. DETAILED DESCRIPTION

[0032] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. The reagents used therein should be understood to be conventional commercial reagents or prepared according to the prior art unless otherwise specified; the operating methods used therein should be understood to be conventional operations in the art unless otherwise specified.

[0033] The method for preparing a high energy-efficiency titanium-based lead dioxide anode provided by the present invention comprises the following steps:

[0034] 1) Titanium plate pretreatment: sandblasting, pickling, rust removal and oil removal; pickling, rust removal and oil removal are carried out simultaneously; the specific operation is: immerse the titanium plate in an environmentally friendly titanium oxide scale cleaning agent at 25-60°C for 5-20 minutes, and rinse it with pure water after taking it out.

[0035] 2) preparing a tin-antimony solution: dissolving a tin salt and an antimony salt in a mixed solvent to prepare a tin-antimony solution; in the embodiment of the present invention, the mixed solvent is prepared by mixing ethanol, ethylene glycol, concentrated hydrochloric acid and deionized water in a volume ratio of 6:2:1:1; the volume proportion of deionized water in the mixed solvent is 5-15%; the molar ratio of tin antimony ions in the tin-antimony solution is 15:1.

[0036] 3) The tin-antimony solution prepared in step 2) is repeatedly applied and sintered on the titanium plate pretreated in step 1) to prepare a tin-antimony oxide intermediate layer.

[0037] 4) Preparation of electroplating solution: adding quaternary ammonium fluoride, cobalt nitrate and bismuth nitrate to a lead nitrate system electroplating solution, and then adding conductive polyaniline for ultrasonic treatment; the conductive polyaniline is doped with dodecylbenzene sulfonic acid to be conductive, and has a molecular weight of 20,000 to 60,000; adding the conductive polyaniline to the lead nitrate system electroplating solution for ultrasonic dispersion for 10 to 60 minutes, stirring at 40 to 60° C. for 10 to 30 minutes, and adding an amount of 0.1 to 1 g / L; the addition amounts of quaternary ammonium fluoride, cobalt nitrate and bismuth nitrate are 0.2 to 0.5 g / L, 0.2 to 0.8 g / L and 0.2 to 0.6 g / L, respectively; the concentration of lead nitrate in the lead nitrate system electroplating solution is 180 to 240 g / L, and the pH value is 1 to 2; in the embodiment of the present invention, the quaternary ammonium fluoride is preferably tetrabutylammonium fluoride; the cobalt nitrate and bismuth nitrate in the electroplating solution of the present invention must be jointly doped to achieve the reduction of power consumption.

[0038] 5) The titanium plate with the tin antimony oxide intermediate layer prepared in step 3) is used as the anode and the titanium mesh is used as the insoluble cathode, and co-deposition is performed in the electroplating solution prepared in step 4), the distance between the cathode and cathode is 1.5 cm, the co-deposition time is 1 to 3 hours, the temperature is 40 to 70° C., and the current density is 10 to 40 mA / cm 2 A high energy efficiency titanium-based lead dioxide anode is obtained.

[0039] Application of a high-efficiency titanium-based lead dioxide anode in the field of electrolytic zinc deposition: The specific operation process of electrolytic zinc deposition is: 125g / L ZnSO 4 and 180g / L H 2 SO 4 The solution is the electrolyte, and an electrolytic cell with two cathodes and one anode is used. High-efficiency titanium-based lead dioxide is used as the anode, and the aluminum plate is used as the cathode. The distance between the anode and cathode is 3 cm, and the current density is 52 mA / cm 2 , and electrochemical deposition is performed at 40° C. In the present invention, the electrolytic zinc deposition is preferably electrolytic extraction of extracted zinc.

[0040] The present invention uses ethanol, ethylene glycol, concentrated hydrochloric acid and a small amount of deionized water as a mixed solvent to prepare a tin-antimony solution. The obtained solution has a high flash point and low cost, and is suitable for industrial application. The tin-antimony oxide prepared from the tin-antimony solution has fewer cracks in the middle layer, can effectively prevent new ecological oxygen from diffusing to the titanium substrate, and can also reduce the oxygen evolution potential.

[0041] The present invention uses quaternary ammonium fluoride, cobalt nitrate and bismuth nitrate to dope and modify PbO 2 Active layer, while using conductive polyaniline as an additive to change the morphology of the active layer, reduce particle size, reduce internal stress, increase specific surface area, and significantly improve the electrochemical performance, catalytic activity and life of the active layer.

[0042] Example 1

[0043] A method for preparing a high-energy-efficiency titanium-based lead dioxide anode comprises the following steps:

[0044] 1) Sandblast the titanium plate, soak it in an environmentally friendly titanium oxide cleaning agent for 20 minutes at 25°C, and then rinse it with pure water;

[0045] 2) Add SnCl with a molar ratio of 15:1 2 and SbCl 3 Dissolved in a mixed solvent of ethanol, ethylene glycol, concentrated hydrochloric acid and deionized water in a volume ratio of 6:2:1:1 to prepare a tin-antimony solution, and applied and sintered on the titanium plate pretreated in step 1) multiple times to prepare a tin-antimony oxide intermediate layer;

[0046] 3) firstly adding 0.2 g / L tetrabutylammonium fluoride, 0.8 g / L cobalt nitrate and 0.2 g / L bismuth nitrate into a lead nitrate system electroplating solution with a lead nitrate concentration of 180 g / L, with a pH of 1 to 2, then adding 0.1 g / L conductive polyaniline, ultrasonically dispersing for 10 min (50 kHz) and stirring at 40° C. for 10 min to prepare an electroplating solution;

[0047] 4) The titanium plate with the tin-antimony oxide intermediate layer prepared in step 2) is used as the anode and the titanium mesh is used as the insoluble cathode, and is placed in the electroplating solution prepared in step 3), with the distance between the cathode and cathode being 1.5 cm and the current density being 40 mA / cm 2 , the co-deposition temperature was 70℃, the co-deposition time was 1h, and a high-efficiency titanium-based lead dioxide anode was obtained.

[0048] Example 2

[0049] A method for preparing a high-energy-efficiency titanium-based lead dioxide anode comprises the following steps:

[0050] 1) Sandblast the titanium plate, soak it in an environmentally friendly titanium oxide cleaning agent at 40°C for 10 minutes, and then rinse it with pure water;

[0051] 2) Add SnCl with a molar ratio of 15:1 2 and SbCl 3 Dissolve in a mixed solvent of ethanol, ethylene glycol, concentrated hydrochloric acid and deionized water in a volume ratio of 6:2:1:1 to prepare a tin-antimony solution, and apply and sinter the solution multiple times on the titanium plate pretreated in step 1) to prepare a tin-antimony oxide intermediate layer;

[0052] 3) firstly adding 0.4 g / L tetrabutylammonium fluoride, 0.4 g / L cobalt nitrate and 0.4 g / L bismuth nitrate into a lead nitrate system electroplating solution with a lead nitrate concentration of 210 g / L, with a pH of 1 to 2, then adding 0.5 g / L conductive polyaniline, ultrasonically dispersing for 30 min (50 kHz) and stirring at 50° C. for 20 min to prepare an electroplating solution;

[0053] 4) The titanium plate with the tin antimony oxide intermediate layer prepared in step 2) is used as the anode and the titanium mesh is used as the insoluble cathode, and is placed in the electroplating solution prepared in step 3), with the distance between the cathode and cathode being 1.5 cm and the current density being 25 mA / cm 2 , the co-deposition temperature was 50°C, the co-deposition time was 1.5h, and a high-efficiency titanium-based lead dioxide anode was obtained.

[0054] Example 3

[0055] A method for preparing a high-energy-efficiency titanium-based lead dioxide anode comprises the following steps:

[0056] 1) Sandblast the titanium plate, soak it in an environmentally friendly titanium oxide cleaning agent at 60°C for 5 minutes, and then rinse it with pure water;

[0057] 2) Add SnCl with a molar ratio of 15:1 2 and SbCl 3 Dissolve in a mixed solvent of ethanol, ethylene glycol, concentrated hydrochloric acid and deionized water in a volume ratio of 6:2:1:1 to prepare a tin-antimony solution, and apply and sinter the solution multiple times on the titanium plate pretreated in step 1) to prepare a tin-antimony oxide intermediate layer;

[0058] 3) firstly adding 0.5 g / L tetrabutylammonium fluoride, 0.2 g / L cobalt nitrate and 0.6 g / L bismuth nitrate into a lead nitrate system electroplating solution with a lead nitrate concentration of 240 g / L, with a pH of 1 to 2, then adding 1 g / L conductive polyaniline, ultrasonically dispersing for 60 min (50 kHz) and stirring at 60° C. for 30 min to prepare an electroplating solution;

[0059] 4) The titanium plate with the tin antimony oxide intermediate layer prepared in step 2) is used as the anode and the titanium mesh is used as the insoluble cathode, and is placed in the electroplating solution prepared in step 3), with the distance between the cathode and cathode being 1.5 cm and the current density being 10 mA / cm 2 , the co-deposition temperature is 40℃, the co-deposition time is 3h, and a high-efficiency titanium-based lead dioxide anode is obtained.

[0060] Comparative Example

[0061] A Ti / Sb-SnO 2 / PbO 2 The method for preparing an anode comprises the following steps:

[0062] 1) The titanium plate is roughened by sandblasting, and then the titanium plate is pickled in an oxalic acid solution (wt 10%) at 98° C. and then rinsed clean;

[0063] 2) Add SnCl with a molar ratio of 15:1 2 and SbCl 3Dissolved in a mixed solvent of ethanol, n-butanol and concentrated hydrochloric acid in a volume ratio of 6:2:2 to prepare a tin-antimony solution, and applied and sintered multiple times on the titanium plate pretreated in step 1) to prepare a tin-antimony oxide intermediate layer;

[0064] 3) The titanium plate with the tin antimony oxide intermediate layer prepared in step 2) is used as the anode and the titanium mesh is used as the insoluble cathode, and is placed in a lead nitrate system electroplating solution with a lead nitrate concentration of 200 g / L, a pH of 1-2, a cathode-cathode distance of 1.5 cm, and a current density of 30 mA / cm 2 , the co-deposition temperature was 60℃, the co-deposition time was 1h, and the traditional Ti / Sb-SnO 2 / PbO 2 anode.

[0065] The performance parameters of the high-efficiency titanium-based lead dioxide anodes prepared in Examples 1 to 3 were tested. Since the performance parameters of the high-efficiency titanium-based lead dioxide anodes in Examples 1 to 3 are relatively similar, only the performance parameters of the high-efficiency titanium-based lead dioxide anode in Example 1 are used for illustration.

[0066] See also Figure 1 (a) and (b) show that the particles are relatively large at the beginning of electrodeposition. Figure 1 (c) and (d) show that as the electrodeposition proceeds, the surface particle morphology changes, the grooves become obvious, and the surface area increases.

[0067] like Figure 2 , Figure 3 As shown, the electrode prepared by the present invention is used as a working electrode, a platinum electrode is used as a counter electrode, and a saturated calomel electrode is used as a reference electrode to form a three-electrode system, and a linear sweep voltammetry curve and an electrochemical impedance spectrum are tested in 25g / L zinc sulfate and 15% sulfuric acid solution by mass fraction; and compared with the linear sweep voltammetry curve and electrochemical impedance spectrum tested by the comparative electrode under the same conditions; from Figure 2 , Figure 3 It can be seen that the oxygen evolution potential and electrochemical impedance of the electrode prepared in Example 1 of the present invention are reduced, and the electrochemical performance is significantly better than that of the comparative example electrode.

[0068] The electrode prepared in Example 1 was used as the anode for the enhanced life test, the titanium electrode was used as the cathode, the electrolyte was a 15% sulfuric acid solution, and the current density was 1A / cm 2 , the cell voltage exceeds 10V and deactivates; compared with the enhanced life of the comparative electrode tested under the same conditions; Figure 4 It can be seen that the enhanced life of the electrode prepared in Example 1 of the present invention can reach 1152 hours, which is 60% longer than that of the electrode in the comparative example.

[0069] The electrode prepared in Example 1 was used as the anode and 125 g / L ZnSO4 and 180 g / L H2SO 4 The solution is the electrolyte, the aluminum plate is the cathode, the distance between the anode and cathode is 3 cm, and the current density is 52 mA / cm 2 , electrolytic zinc deposition was carried out at 40°C; the results of electrolytic zinc deposition were compared with those of comparative electrodes tested under the same conditions; Figure 5 It can be seen that the current efficiency of the electrode prepared in Example 1 of the present invention can reach 97%, which is higher than the current efficiency of the comparative electrode, and the DC power consumption is reduced by 150 kWh / t compared with the comparative electrode, thereby improving the energy efficiency of zinc electrowinning.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a high energy efficiency titanium-based lead dioxide anode, characterized in that: The following steps are involved: 1) Titanium plate pretreatment: sandblasting, pickling, rust removal and oil removal; 2) preparing a tin-antimony solution: dissolving a tin salt and an antimony salt in a mixed solvent to prepare a tin-antimony solution; the mixed solvent is prepared from ethanol, ethylene glycol, concentrated hydrochloric acid and deionized water; 3) brushing and sintering the tin-antimony solution prepared in step 2) on the titanium plate pretreated in step 1) multiple times to prepare a tin-antimony oxide intermediate layer; 4) Preparation of electroplating solution: adding quaternary ammonium fluoride, cobalt nitrate and bismuth nitrate to the lead nitrate system electroplating solution, and then adding conductive polyaniline for ultrasonic treatment; 5) The titanium plate with the tin-antimony oxide intermediate layer prepared in step 3) is used as the anode, and the titanium mesh is used as the insoluble cathode, and co-deposited in the electroplating solution prepared in step 4) to prepare a multi-component composite active layer to obtain a high-efficiency titanium-based lead dioxide anode.

2. The method for preparing a high energy efficiency titanium-based lead dioxide anode according to claim 1, characterized in that: In the step 1), the titanium plate is pickled, rusted and degreased simultaneously; the specific operation is: immerse the titanium plate in an environmentally friendly titanium oxide scale cleaning agent at 25 to 60° C. for 5 to 20 minutes, and then rinse it with pure water after taking it out.

3. The method for preparing a high energy efficiency titanium-based lead dioxide anode according to claim 1, characterized in that: The volume proportion of deionized water in the mixed solvent of step 2) is 5-15%.

4. The method for preparing a high energy efficiency titanium-based lead dioxide anode according to claim 1, characterized in that: Step 2) The molar ratio of tin antimony ions in the tin antimony solution is 15:

1.

5. The method for preparing a high energy efficiency titanium-based lead dioxide anode according to claim 1, characterized in that: The conductive polyaniline in step 4) is doped with dodecylbenzene sulfonic acid to be conductive, and has a molecular weight of 20,000 to 60,000; the conductive polyaniline is added to a lead nitrate system electroplating solution and ultrasonically dispersed for 10 to 60 minutes, stirred at 40 to 60° C. for 10 to 30 minutes, and the added amount is 0.1 to 1 g / L.

6. The method for preparing a high energy efficiency titanium-based lead dioxide anode according to claim 1, characterized in that: In step 4), the addition amounts of the quaternary ammonium fluoride salt, cobalt nitrate and bismuth nitrate are 0.2-0.5 g / L, 0.2-0.8 g / L and 0.2-0.6 g / L respectively.

7. The method for preparing a high energy efficiency titanium-based lead dioxide anode according to claim 1, characterized in that: The concentration of lead nitrate in the lead nitrate system electroplating solution in step 4) is 180-240 g / L, and the pH value is 1-2.

8. The method for preparing a high energy efficiency titanium-based lead dioxide anode according to claim 1, characterized in that: The conditions for preparing the multi-component composite active layer by co-deposition in step 4) are: the current density is 10-40 mA / cm 2 , temperature is 40-70℃, time is 1-3h.

9. Use of the high energy efficiency titanium-based lead dioxide anode according to any one of claims 1 to 8 in the field of zinc electrowinning.

10. The use according to claim 9, characterized in that: The specific operation process of electrolytic zinc deposition is as follows: using a solution of 125 g / L ZnSO4 and 180 g / L H2SO4 as the electrolyte, using an electrolytic cell with two cathodes and one anode, using high-efficiency titanium-based lead dioxide as the anode, an aluminum plate as the cathode, a cathode-cathode distance of 3 cm, and a current density of 52 mA / cm 2 , electrochemical deposition was carried out at 40 °C.

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