CN115287737B - Titanium-based gradient composite manganese dioxide anode plate and preparation method thereof - Google Patents

Abstract

The present invention relates to a titanium-based gradient composite manganese dioxide anode plate and a preparation method thereof, and belongs to the technical field of non-ferrous metal electrowinning. The titanium-based gradient composite manganese dioxide anode plate of the present invention comprises a titanium-clad aluminum conductive beam and a titanium-based oxide anode plate, and the titanium-based oxide anode plate comprises a titanium plate, a titanium-clad aluminum composite rod, a double-layer titanium mesh and a titanium rod, the top of the titanium plate is fixedly connected to the bottom of the titanium-clad aluminum conductive beam, the titanium-clad aluminum composite rod is vertically arranged at the bottom of the titanium plate, the double-layer titanium mesh is arranged between adjacent titanium-clad aluminum composite rods, the titanium rod is arranged at the bottom of the titanium-clad aluminum composite rod, the top of the double-layer titanium mesh is fixedly connected to the titanium plate, and the bottom of the double-layer titanium mesh is fixedly connected to the titanium rod; the titanium surfaces on the titanium plate, the titanium-clad aluminum composite rod, the double-layer titanium mesh and the titanium rod are sequentially coated with a metal oxide intermediate layer and a composite manganese dioxide active layer. The present invention is applied to non-ferrous metal electrowinning, and compared with traditional lead alloy anodes, the cell voltage is reduced, the service life is extended, the current efficiency is improved, and the cathode product quality is high.

Description

A titanium-based gradient composite manganese dioxide anode plate and a preparation method thereof

Technical Field

The invention relates to a titanium-based gradient composite manganese dioxide anode plate and a preparation method thereof, belonging to the technical field of nonferrous metal electrodeposition.

Background technique

In the process of non-ferrous metal smelting, more than 90% of zinc and about 30% of copper are extracted by hydrometallurgical technology. Especially in the process of hydrometallurgical zinc smelting, the electrolytic process consumes 2/3 of the energy consumption of the entire zinc extraction process. The production energy consumption of hydrometallurgical zinc smelting is 3200-4200kwh/t.Zn. The oxygen evolution potential of industrial lead alloy anode is as high as about 1V, which will increase the useless power consumption by about 1000kWh, accounting for about 30% of the total energy consumption of zinc electrolytic deposition.

At present, there are four main types of anode materials used at home and abroad:

The first type of lead alloy anode: due to its poor corrosion resistance, toxicity and harm to the human body, solution pollution, easy deformation during electrolysis, and precipitation at the cathode, the production of lead-based alloy anodes is highly polluting and does not comply with national policies, and is gradually being eliminated from the market;

The second type of titanium-based platinum group oxide coated anode: The precious metal coated titanium anode has good performance, is not consumed during the electrolysis process, has good stability, low oxygen evolution overpotential, and high catalytic activity, but its high price limits its large-scale application;

The third type of titanium-based lead dioxide coated anode: The titanium-based lead dioxide anode inherits the advantages of the coated titanium anode and the lead anode. It fully combines the good appearance stability of the titanium anode and the price advantage of the lead anode, and fully overcomes the disadvantages of the lead anode, such as easy corrosion, easy bending, and high price of the coated titanium anode. However, the following problems may occur during use: (1) The _PbO2 deposit layer is not tightly bonded to the electrode surface or the deposit layer is uneven; (2) The _PbO2 deposit layer has ceramic brittleness, and the denser the PbO2 deposit layer, the greater the internal stress; (3) The conductive and corrosion-resistant β- _PbO2 deposit layer is not strongly bonded to the titanium matrix and is easy to fall off during use; (4) The cell voltage of the _PbO2 electrode is high in electrolytic applications.

The fourth type is titanium-based manganese dioxide coated anode: The advantages of manganese dioxide coated anode are: low oxygen evolution overpotential, good corrosion resistance, and high purity of cathode product; the disadvantages are: complex preparation process and high cost; in addition, most manganese dioxide coated anodes will have obvious cracks on their surface. During the long electrolysis process, the substrate is easily exposed, increasing the corrosion rate of the metal substrate. If the substrate is titanium-based, it will oxidize on the exposed substrate surface to generate non-conductive titanium dioxide, resulting in increased voltage and increased energy consumption.

In addition, the titanium-based anodes currently produced industrially are prone to deformation in actual use, which can easily cause a short circuit between the anode and the cathode. In severe cases, the anode may be seriously damaged, resulting in increased power consumption and reduced quality of the cathode product.

Therefore, there is an urgent need to develop anodes with high current efficiency, low energy consumption, low price, simple process and high cathode product quality (low lead content).

Summary of the invention

Aiming at the problem that titanium-based anodes are prone to deformation in actual use in industrial production, which can easily cause a short circuit between the cathode and the anode, and can seriously damage the anode, resulting in increased power consumption and reduced quality of cathode products, the present invention provides a titanium-based gradient composite manganese dioxide anode plate and a preparation method thereof. The present invention embeds Ag-doped carbon fiber-β- _PbO2 composite particles into a tungsten-containing γ- _MnO2 coating, which greatly improves the conductivity of γ- _MnO2 and reduces the internal stress of the coating, thereby increasing the service life of the composite manganese dioxide electrode and reducing the cell voltage; at the same time, Sn-Ru-TaOx-coated hollow glass microspheres are embedded in the tungsten-containing γ- _MnO2 coating, which not only improves the catalytic activity of γ- _MnO2 , but also greatly reduces the brittleness of the γ- _MnO2 coating, so that the electrode has better stability during use; the titanium-based gradient composite manganese dioxide anode plate is applied to non-ferrous metal electrowinning, and compared with traditional lead alloy anodes, the cell voltage is reduced by more than 8%, the service life is extended by more than 1 times, the current efficiency is increased by more than 2%, and the cathode product quality is high.

A titanium-based gradient composite manganese dioxide anode plate, comprising a titanium-clad aluminum conductive beam 1 and a titanium-based oxide anode plate 2, wherein the titanium-based oxide anode plate 2 is fixedly arranged at the bottom end of the titanium-clad aluminum conductive beam 1, and an insulator 7 is arranged on the titanium-based oxide anode plate 2;

The titanium-based oxide anode plate 2 includes a titanium plate 3, a titanium-clad aluminum composite rod 4, a double-layer titanium mesh 5 and a titanium rod 6. The top of the titanium plate 3 is fixedly connected to the bottom of the titanium-clad aluminum conductive beam 1, the titanium-clad aluminum composite rod 4 is vertically arranged at the bottom of the titanium plate 3, and the titanium rod 6 is arranged at the bottom of the titanium-clad aluminum composite rod 4. The titanium plate 3, the titanium-clad aluminum composite rod 4 and the titanium rod 6 form a titanium-based oxide anode plate frame. The double-layer titanium mesh 5 is arranged between adjacent titanium-clad aluminum composite rods 4. The top of the double-layer titanium mesh 5 is fixedly connected to the titanium plate 3, and the bottom of the double-layer titanium mesh 5 is fixedly connected to the titanium rod 6; the titanium surface of the titanium-based oxide anode plate frame is sequentially coated with a metal oxide intermediate layer I and a composite manganese dioxide active layer, and the titanium surface of the double-layer titanium mesh 5 is sequentially coated with a metal oxide intermediate layer II and a composite manganese dioxide active layer.

The thickness of the titanium layer of the titanium-clad aluminum conductive beam 1 is 1 to 3 mm, a copper-aluminum composite conductive head is welded to one end of the titanium-clad aluminum conductive beam 1, the thickness of the titanium plate 3 is 3 to 5 mm, the thickness of the titanium layer of the titanium-clad aluminum composite rod 4 is 0.5 to 2 mm, the long axis of the double-layer titanium mesh 5 is 3 to 16 mm, the short axis is 1 to 6 mm, and the cross-sectional thickness is 0.5 to 3 mm; the thickness of the metal oxide intermediate layer I and the metal oxide intermediate layer II is 1 to 5 μm, and the thickness of the composite manganese dioxide active layer is 0.3 to 2 mm.

The metal oxide intermediate layer I is Sn-SbOx, the metal oxide intermediate layer II is a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer, and the composite manganese dioxide active layer contains Ag-doped carbon fiber-β- _PbO2 composite particles, Sn-Ru-TaOx coated hollow glass microspheres and γ- _MnO2 .

Furthermore, the particle size of the carbon fiber is 1 to 10 μm, the particle size of the Ag-doped carbon fiber-β- _PbO2 composite particles is 10 to 100 μm, and the particle size of the hollow glass microspheres is 10 to 100 μm.

Furthermore, the molar ratio of Pt, Sn and Sb in the Pt-Sn-SbOx is 1-7:80-87:6-19, the molar ratio of Pd, Ti, Sn and Sb in the Pd-Ti-Sn-SbOx is 1-5:3-8:70-85:2-24, and the molar ratio of Sn and Sb in the Sn-SbOx is 70-80:20-30.

Furthermore, taking the mass percentage of the composite manganese dioxide active layer as 100%, the Ag-doped carbon fiber-β- _PbO2 composite particles account for 1-6%, the Sn-Ru-TaOx coated hollow glass microspheres account for 0.5-4%, W accounts for 0.05-2%, and the rest is γ- _MnO2 ; the mass percentage of Ag in the Ag-doped carbon fiber-β- _PbO2 composite particles is 0.5-5%, the mass percentage of carbon fiber powder is 0.1-1%, and the rest is β- _PbO2 ; the molar ratio of Sn, Ru and Ta in the Sn-Ru-TaOx coated hollow glass microspheres is 40-50:30-42:8-30, and the Sn-Ru-TaOx oxide accounts for 1-8% of the mass of the Sn-Ru-TaOx coated hollow glass microspheres.

Furthermore, the preparation method of the Ag-doped carbon fiber-β- _PbO2 composite particles comprises the following specific steps:

With stainless steel as anode and titanium mesh as cathode, Ag-doped carbon fiber-β-PbO ₂ composite coating is obtained by electrodeposition in acidic lead nitrate composite plating solution for 4-8 hours, and Ag-doped carbon fiber- _{β-PbO 2 composite coating is stripped and then ball-milled to obtain Ag-doped carbon fiber-β-PbO 2 composite} particles; wherein the acidic lead nitrate composite plating solution contains 50-200 g/L lead nitrate, 0.5-20 g/L silver nitrate, 4-20 g/L thiourea and 4-20 g/L carbon fiber particles, and the pH value of the acidic lead nitrate composite plating solution is 0-2; the electrodeposition temperature is 60-90°C, and the current density is 6-12 A/dm ² .

Furthermore, the preparation method of the Sn-Ru-TaOx coated hollow glass microspheres comprises the following specific steps:

1) dissolving tin chloride, ruthenium chloride and tantalum chloride in concentrated hydrochloric acid, adding n-butanol solvent, and removing water by rotary evaporation to obtain a tin-ruthenium-tantalum precursor liquid;

2) calcining the hollow glass microspheres at a temperature of 400-600° C. for 0.5-2 h, immersing them in a NaOH solution with a concentration of 5-10 wt.%, treating them at a temperature of 60-90° C. for 5-40 min, washing them with deionized water, immersing them in a HF solution with a concentration of 0.5-2 wt.% for 1-5 min, washing with deionized water, and drying them to obtain pretreated hollow glass microspheres;

3) The pretreated hollow glass microspheres are immersed in a tin-ruthenium-tantalum precursor solution for ultrasonic immersion for 5 to 10 minutes, dried at a temperature of 100 to 150° C., and then calcined at a temperature of 300 to 560° C. for 10 to 20 minutes. The ultrasonic immersion and calcination process are repeated 6 to 12 times, and then sintered at a temperature of 400 to 480° C. for 1 to 2 hours to obtain Sn-Ru-TaOx coated hollow glass microsphere composite particles.

The preparation method of the titanium-based gradient composite manganese dioxide anode plate comprises the following specific steps:

(1) After degreasing and pickling, the aluminum rod is immersed in a NaOH solution for 1 to 5 minutes, washed with deionized water, and then immersed in a _HNO3 solution for activation for 4 to 8 minutes to obtain an activated aluminum rod; the inner wall of the titanium tube is treated with an HF solution and washed with deionized water to obtain a pretreated titanium tube; the pretreated titanium tube is sleeved outside the aluminum rod and extruded and drawn for compounding, hot-rolled to obtain a titanium-clad aluminum composite rod, and the titanium-clad aluminum composite rod is welded with an aluminum-copper composite conductive head to obtain a titanium-clad aluminum conductive beam;

(2) welding a titanium plate, a titanium-clad aluminum composite rod and a titanium rod to form a titanium-based oxide anode plate frame, immersing the titanium-based oxide anode plate frame in a NaOH solution for 10 to 30 minutes, performing a heat treatment after sandblasting surface treatment on the titanium-based oxide anode plate frame, and then placing the frame in an oxalic acid solution for activation for 0.5 to 2.0 hours to obtain an activated titanium-based oxide anode plate frame, coating the surface of the activated titanium-based oxide anode plate frame with a tin-antimony precursor liquid, drying and sintering pretreatment for 5 to 10 minutes, repeating the tin-antimony precursor liquid coating and sintering process for 3 to 10 times, and then placing the frame at a temperature of 400 to 600° C. for 1 to 2 hours to obtain a titanium-based oxide anode plate frame coated with a metal oxide intermediate layer;

(3) The drawn titanium mesh is immersed in a NaOH solution for 10 to 30 minutes, the titanium mesh is subjected to a sandblasting surface treatment and then subjected to a heat treatment, and then placed in an oxalic acid solution for activation for 0.5 to 2.0 hours to obtain an activated titanium mesh, the surface of the activated titanium mesh is coated with a platinum-tin-antimony precursor solution or a palladium-titanium-tin-antimony precursor solution, and then sintered for 5 to 10 minutes after drying, the coating and sintering process is repeated 3 to 10 times, and then placed at a temperature of 400 to 600° C. for 1 to 2 hours to obtain a titanium mesh coated with Pt-Sn-SbOx or Pd-T i-Sn-Sb titanium mesh; coating a tin-antimony precursor liquid on the surface of a titanium mesh coated with Pt-Sn-SbOx or Pd-Ti-Sn-Sb, drying and sintering for 5 to 10 minutes, repeating the coating of the tin-antimony precursor liquid and the sintering process for 3 to 10 times, and then sintering at a temperature of 400 to 600° C. for 1 to 2 hours to obtain a titanium mesh coated with a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer;

(4) welding a titanium mesh coated with a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer onto a titanium-based oxide anode plate frame coated with a metal oxide intermediate layer to form a titanium-based oxide anode plate blank, wherein the titanium mesh coated with the Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or the Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer is located between adjacent titanium-clad aluminum composite rods; using the titanium-based oxide anode plate blank as an anode and the titanium plate as a cathode, placing the blank in a manganese nitrate composite electroplating solution for composite electrodeposition, washing with deionized water, and drying to obtain a titanium-based oxide anode plate;

(5) The top end of the titanium plate of the titanium-based oxide anode plate is welded to the bottom end of the titanium-clad aluminum conductive beam, and the insulator is installed on the titanium-based oxide anode plate to obtain a titanium-based gradient composite manganese dioxide anode plate.

In the step (1), the concentration of the NaOH solution is 5-10wt.%, the immersion temperature of the NaOH solution is 40-70°C, the concentration of the _HNO3 solution is 10-40wt.%, the concentration of the HF solution is 1-10wt.%, the hot rolling temperature is 500-700°C, and the welding method is pulse argon gas shielded aluminum-aluminum welding;

Step (2) The concentration of NaOH solution is 10-20wt.%, the soaking temperature of NaOH solution is 50-80°C, the heat treatment temperature is 400-700°C, the heat treatment time is 0.2-1.5h, the concentration of oxalic acid solution is 5-30wt.%, the activation temperature is 80-100°C, and the sintering pretreatment temperature is 400-700°C;

Step (3) the concentration of NaOH solution is 10-20wt.%, the soaking temperature of NaOH solution is 50-80°C, the heat treatment temperature is 400-700°C, the heat treatment time is 0.2-1.5h, the concentration of oxalic acid solution is 5-30wt.%, the activation temperature is 80-100°C, and the sintering pretreatment temperature is 400-700°C;

The temperature of the composite electrodeposition in step (4) is 80-100° C., the current density is 1-5 A/dm ² , the stirring speed is 50-300 rpm, and the composite electrodeposition time is 4-20 h. The manganese nitrate composite electroplating solution contains 20-100 g/L manganese nitrate (Mn(NO ₃ ) ₂ ), 2-30 g/L nitric acid (HNO ₃ ), 10-40 g/L sodium tungstate (Na ₂ WO ₄ ), 10-30 g/L Ag-doped carbon fiber-β-PbO ₂ composite particles, and 4-30 g/L Sn-Ru-TaOx coated hollow glass microspheres.

The palladium-titanium-tin-antimony precursor liquid is prepared by adding palladium chloride, tetrabutyl titanate, tin chloride and antimony chloride in a molar ratio into concentrated hydrochloric acid until they are completely dissolved, then adding n-butanol solvent, and removing water from the coating liquid by a rotary evaporator to obtain a palladium-titanium-tin-antimony precursor liquid;

The platinum tin antimony precursor liquid is prepared by adding chloroplatinic acid (H ₂ PtCl ₆ ·6H ₂ O), tin chloride and antimony chloride in a molar ratio into concentrated hydrochloric acid until they are completely dissolved, then adding n-butanol solvent, and removing water from the coating liquid by a rotary evaporator to obtain a platinum tin antimony precursor liquid;

The tin-antimony precursor liquid is prepared by adding tin chloride and antimony chloride in a molar ratio into concentrated hydrochloric acid until they are completely dissolved, then adding n-butanol solvent, and removing water from the coating liquid by a rotary evaporator to obtain the tin-antimony precursor liquid.

The beneficial effects of the present invention are:

(1) The titanium-based gradient composite manganese dioxide anode plate of the present invention is used for non-ferrous metal electrowinning, and has good electrocatalytic activity, long service life, low cost and high electrical efficiency. Compared with the traditional lead-based multi-element alloy, without changing the electrolytic cell structure, electrolyte composition and operating specifications, the cell voltage can be reduced by more than 8%, the service life is extended by more than 1 times, the current efficiency is increased by more than 2%, and the cathode product quality is high;

(2) The present invention uses titanium-clad aluminum conductive beams/rods, which can not only reduce the material cost of the electrode, but also avoid the introduction of impurity ions (Cu ²⁺ ) into the cathode product;

(3) The introduction of Pd and Pt elements into the metal oxide intermediate layer of the titanium-based gradient composite manganese dioxide anode plate of the present invention can not only increase the surface area of the coating and make the coating easier to form a network structure, but also increase the conductivity of the coating and reduce the interface resistance between the titanium base and the coating;

(4) The present invention adopts a double-layer titanium mesh electrode, which increases the apparent surface area of the electrode by 1 times, improves the catalytic activity of the active layer, and reduces the cell voltage of the electrode during the electrowinning process;

(5) The present invention embeds Ag-doped carbon fiber-β- _PbO2 composite particles into the tungsten-containing γ- _MnO2 coating, which greatly improves the electrical conductivity of γ- _MnO2 and reduces the internal stress of the coating, thereby increasing the service life of the composite manganese dioxide electrode and reducing the cell voltage; at the same time, Sn-Ru-TaOx-coated hollow glass microspheres are embedded in the tungsten-containing γ- _MnO2 coating, which not only improves the catalytic activity of γ- _MnO2 , but also greatly reduces the brittleness of the γ- _MnO2 coating, thereby making the electrode more stable during use; the addition of Ag-doped carbon fiber-β- _PbO2 composite particles and Sn-Ru-TaOx-coated hollow glass microspheres to the electrodeposited manganese dioxide plating solution can increase the anode current density of the electrodeposition by more than 4 times, and will not produce a rough γ- _MnO2 coating.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of a titanium-based gradient composite manganese dioxide anode plate;

Fig. 2 is a schematic cross-sectional view taken along line A-A of Fig. 1;

Fig. 3 is a schematic cross-sectional view taken along line B-B of Fig. 2;

Fig. 4 is a schematic cross-sectional view taken along line C-C of Fig. 1;

In the figure: 1-titanium-clad aluminum conductive beam, 1a-copper-aluminum composite conductive head, 2-titanium-based oxide anode plate, 3-titanium plate, 4-titanium-clad aluminum composite rod, 5-double-sided titanium mesh, 5a-titanium matrix, 5b-metal oxide intermediate layer, 5c-composite manganese dioxide active layer, 6-titanium rod, 7-insulator.

Detailed ways

The present invention is further described in detail below in conjunction with specific implementation modes, but the protection scope of the present invention is not limited to the described contents.

The titanium-based gradient composite manganese dioxide anode plate of the present invention (see FIGS. 1 to 4 ) comprises a titanium-clad aluminum conductive beam 1 and a titanium-based oxide anode plate 2, wherein the titanium-based oxide anode plate 2 is fixedly arranged at the bottom end of the titanium-clad aluminum conductive beam 1, and an insulator 7 is arranged on the titanium-based oxide anode plate 2;

The titanium-based oxide anode plate 2 comprises a titanium plate 3, a titanium-clad aluminum composite rod 4, a double-layer titanium mesh 5 and a titanium rod 6. The top of the titanium plate 3 is fixedly connected to the bottom of the titanium-clad aluminum conductive beam 1. The titanium-clad aluminum composite rod 4 is vertically arranged at the bottom of the titanium plate 3. The titanium rod 6 is arranged at the bottom of the titanium-clad aluminum composite rod 4. The titanium plate 3, the titanium-clad aluminum composite rod 4 and the titanium rod 6 form a titanium-based oxide anode plate frame. The double-layer titanium mesh 5 is arranged between adjacent titanium-clad aluminum composite rods 4. The top of the double-layer titanium mesh 5 is fixedly connected to the titanium plate 3, and the bottom of the double-layer titanium mesh 5 is fixedly connected to the titanium rod 6. The titanium surface of the titanium-based oxide anode plate frame is coated with a metal oxide intermediate layer I and a composite manganese dioxide active layer in sequence, and the titanium surface of the double-layer titanium mesh 5, i.e., the titanium substrate 5a, is coated with a metal oxide intermediate layer II5b and a composite manganese dioxide active layer 5c in sequence.

The length of the titanium-clad aluminum conductive beam 1 is 600-1500 mm, the width is 20-50 mm, and the height is 30-60 mm. The thickness of the titanium layer of the titanium-clad aluminum conductive beam 1 is 1-3 mm. A copper-aluminum composite conductive head 1a is welded to one end of the titanium-clad aluminum conductive beam 1. The copper-aluminum composite conductive head 1a is 50-200 mm long, 20-50 mm wide, and 10-30 mm high. The thickness of the titanium plate 3 is 3-5 mm. The titanium-clad aluminum composite rod 4 is round or square, and the diameter of the round rod aluminum is The cross-sectional length of the square aluminum is 4 to 10 mm and the width is 1 to 4 mm. The titanium layer thickness of the titanium-clad aluminum composite rod 4 is 0.5 to 2 mm. The long axis of the double-layer titanium mesh 5 is 3 to 16 mm and the short axis is 1 to 6 mm. The titanium rod 6 is a round rod or a square rod, wherein the diameter of the round rod is The cross-section of the square rod is 4 to 10 mm long and 3 to 5 mm wide; the thickness of the metal oxide intermediate layer I and the metal oxide intermediate layer II is 1 to 5 μm, and the thickness of the composite manganese dioxide active layer is 0.3 to 2 mm;

The metal oxide intermediate layer I is Sn-SbOx, the metal oxide intermediate layer II is a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer, and the composite manganese dioxide active layer contains Ag-doped carbon fiber-β-PbO ₂ composite particles, Sn-Ru-TaOx coated hollow glass microspheres and γ-MnO ₂ ;

The particle size of carbon fiber is 1 to 10 μm, the particle size of Ag-doped carbon fiber-β-PbO ₂ composite particles is 10 to 100 μm, and the particle size of hollow glass microspheres is 10 to 100 μm;

The molar ratio of Pt, Sn and Sb in Pt-Sn-SbOx is 1-7:80-87:6-19, the molar ratio of Pd, Ti, Sn and Sb in Pd-Ti-Sn-SbOx is 1-5:3-8:70-85:2-24, and the molar ratio of Sn and Sb in Sn-SbOx is 70-80:20-30;

Taking the mass percentage of the composite manganese dioxide active layer as 100%, the Ag-doped carbon fiber-β- _PbO2 composite particles account for 1-6%, the Sn-Ru-TaOx coated hollow glass microspheres account for 0.5-4%, W accounts for 0.05-2%, and the rest is γ- _MnO2 ; the mass percentage of Ag in the Ag-doped carbon fiber-β- _PbO2 composite particles is 0.5-5%, the mass percentage of carbon fiber powder is 0.1-1%, and the rest is β- _PbO2 ; the molar ratio of Sn, Ru and Ta in the Sn-Ru-TaOx coated hollow glass microspheres is 40-50:30-42:8-30, and the Sn-Ru-TaOx oxide accounts for 1-8% of the mass of the Sn-Ru-TaOx coated hollow glass microspheres;

The preparation method of Ag-doped carbon fiber-β- _PbO2 composite particles comprises the following specific steps:

With stainless steel as anode and titanium mesh as cathode, Ag-doped carbon fiber-β-PbO ₂ composite coating is obtained by electroplating in an acidic lead nitrate composite plating solution for 4-8 hours, and Ag-doped carbon fiber- _{β-PbO 2 composite coating is stripped and ball-milled to obtain Ag-doped carbon fiber-β-PbO 2 composite} particles; wherein the acidic lead nitrate composite plating solution contains 50-200 g/L lead nitrate, 0.5-20 g/L silver nitrate, 4-20 g/L thiourea and 4-20 g/L carbon fiber particles, and the pH value of the acidic lead nitrate composite plating solution is 0-2; the electrodeposition temperature is 60-90°C, and the current density is 6-12 A/dm ² ;

The preparation method of Sn-Ru-TaOx coated hollow glass microspheres, the specific steps are as follows:

1) dissolving tin chloride, ruthenium chloride and tantalum chloride in concentrated hydrochloric acid, adding n-butanol solvent, and removing water by rotary evaporation to obtain a tin-ruthenium-tantalum precursor liquid;

2) calcining the hollow glass microspheres at a temperature of 400-600° C. for 0.5-2 h, immersing them in a NaOH solution with a concentration of 5-10 wt.%, treating them at a temperature of 60-90° C. for 5-40 min, washing them with deionized water, immersing them in a HF solution with a concentration of 0.5-2 wt.% for 1-5 min, washing with deionized water, and drying them to obtain pretreated hollow glass microspheres;

3) immersing the pretreated hollow glass microspheres in a tin-ruthenium-tantalum precursor solution for ultrasonic immersion for 5 to 10 minutes, drying at 100 to 150° C., calcining at a temperature of 300 to 560° C. for 10 to 20 minutes, repeating the ultrasonic immersion and calcining process for 6 to 12 times, and then sintering at a temperature of 400 to 480° C. for 1 to 2 hours to obtain Sn-Ru-TaOx coated hollow glass microsphere composite particles;

The present invention embeds Ag-doped carbon fiber-β- _PbO2 composite particles into a tungsten-containing γ- _MnO2 coating, greatly improving the electrical conductivity of the γ- _MnO2 and reducing the internal stress of the coating, thereby increasing the service life of the composite manganese dioxide electrode and reducing the cell voltage; at the same time, Sn-Ru-TaOx-coated hollow glass microspheres are embedded in the tungsten-containing γ- _MnO2 coating, which not only improves the catalytic activity of the γ- _MnO2 , but also greatly reduces the brittleness of the γ- _MnO2 coating, thereby making the electrode more stable during use; the addition of Ag-doped carbon fiber-β- _PbO2 composite particles and Sn-Ru-TaOx-coated hollow glass microspheres into the electrodeposited manganese dioxide plating solution can increase the anode current density of the electrodeposition by more than 4 times, and will not produce a rough γ- _MnO2 coating.

Example 1: The titanium-based gradient composite manganese dioxide anode plate of this example (see Figures 1 to 4);

The titanium-clad aluminum conductive beam 1 has a length of 1200 mm, a width of 40 mm, and a height of 50 mm. The thickness of the titanium layer of the titanium-clad aluminum conductive beam 1 is 2 mm. A copper-aluminum composite conductive head 1a is welded to one end of the titanium-clad aluminum conductive beam 1. The copper-aluminum composite conductive head 1a has a length of 100 mm, a width of 36 mm, and a height of 46 mm. The titanium plate 3 has a thickness of 4 mm. The titanium-clad aluminum composite rod 4 is round, and the diameter of the round rod aluminum is The titanium layer thickness of the titanium-clad aluminum composite rod 4 is 1.5 mm, the double-layer titanium mesh 5 has a long axis of 10 mm, a short axis of 5 mm, and a cross-sectional thickness of 1.0 mm; the titanium rod 6 is a round rod, wherein the diameter of the round rod is The thickness of the metal oxide intermediate layer I is 2 μm, the thickness of the metal oxide intermediate layer II is 3 μm, and the thickness of the composite manganese dioxide active layer is 0.4 mm;

The metal oxide intermediate layer I is Sn-SbOx, the metal oxide intermediate layer II is a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer, and the composite manganese dioxide active layer contains Ag-doped carbon fiber-β-PbO ₂ composite particles, Sn-Ru-TaOx coated hollow glass microspheres and γ-MnO ₂ ;

The particle size of carbon fiber is 1 μm, the particle size of Ag-doped carbon fiber-β-PbO ₂ composite particles is 10 μm, and the particle size of hollow glass microspheres is 10 μm;

The molar ratio of Pt, Sn and Sb in Pt-Sn-SbOx is 3:86:11, and the molar ratio of Sn and Sb in Sn-SbOx is 70:30;

Taking the mass percentage of the composite manganese dioxide active layer as 100%, the Ag-doped carbon fiber-β-PbO ₂ composite particles account for 1.0%, the Sn-Ru-TaOx coated hollow glass microspheres account for 0.5%, W accounts for 0.1%, and the rest is γ-MnO ₂ ; the mass percentage of Ag in the Ag-doped carbon fiber-β-PbO ₂ composite particles is 0.5%, the mass percentage of carbon fiber powder is 0.1%, and the rest is β-PbO ₂ ; the molar ratio of Sn, Ru and Ta in the Sn-Ru-TaOx coated hollow glass microspheres is 40:30:30, and the Sn-Ru-TaOx oxide accounts for 1.0% of the mass of the Sn-Ru-TaOx coated hollow glass microspheres;

The preparation method of Ag-doped carbon fiber-β- _PbO2 composite particles comprises the following specific steps:

With stainless steel as anode and titanium mesh as cathode, Ag-doped carbon fiber-β-PbO ₂ composite coating was obtained by electroplating in acidic lead nitrate composite plating solution for 4 hours, and Ag-doped carbon fiber-β-PbO ₂ composite coating was stripped and then ball-milled to obtain Ag-doped carbon fiber-β-PbO ₂ composite particles; wherein the acidic lead nitrate composite plating solution contained 50 g/L lead nitrate, 0.5 g/L silver nitrate, 4 g/L thiourea and 4 g/L carbon fiber particles, and the pH value of the acidic lead nitrate composite plating solution was 0; the electrodeposition temperature was 60°C, and the current density was 6A/dm ² ;

The preparation method of Sn-Ru-TaOx coated hollow glass microspheres, the specific steps are as follows:

1) dissolving tin chloride, ruthenium chloride and tantalum chloride in concentrated hydrochloric acid, adding n-butanol solvent, and removing water by rotary evaporation to obtain a tin-ruthenium-tantalum precursor liquid;

2) calcining the hollow glass microspheres at 400° C. for 0.5 h, immersing them in a 5 wt.% NaOH solution at 60° C. for 5 min, washing them with deionized water, immersing them in a 0.5 wt.% HF solution for 1 min, washing them with deionized water, and drying them to obtain pretreated hollow glass microspheres;

3) The pretreated hollow glass microspheres were immersed in a Sn-Ru-Tantalum precursor solution and ultrasonically immersed for 5 minutes, dried at 100° C., and then calcined at 300° C. for 10 minutes. The ultrasonic immersion and calcination process was repeated 6 times, and then sintered at 480° C. for 1 hour to obtain Sn-Ru-TaOx coated hollow glass microsphere composite particles;

The preparation method of the titanium-based gradient composite manganese dioxide anode plate comprises the following specific steps:

(1) After degreasing and pickling, the aluminum rod is immersed in a 5wt.% NaOH solution at 40°C for 1 min, washed with deionized water, and then immersed in a 10wt.% _HNO3 solution for activation for 4 min to obtain an activated aluminum rod; the inner wall of the titanium tube is treated with a 1wt.% HF solution and washed with deionized water to obtain a pretreated titanium tube; the pretreated titanium tube is sleeved outside the aluminum rod and extruded and drawn to obtain a composite, and hot rolled at 500°C to obtain a titanium-clad aluminum composite rod, and the titanium-clad aluminum composite rod is welded to an aluminum-copper composite conductive head (pulse argon gas protection aluminum-aluminum welding) to obtain a titanium-clad aluminum conductive beam;

(2) welding a titanium plate, a titanium-clad aluminum composite rod and a titanium rod to form a titanium-based oxide anode plate frame, immersing the titanium-based oxide anode plate frame in a NaOH solution with a concentration of 10 wt.%, and soaking it at a temperature of 50° C. for 10 min. After the titanium-based oxide anode plate frame is subjected to sandblasting surface treatment, it is heat-treated at a temperature of 400° C. for 0.2 h, and then placed in a 5 wt.% oxalic acid solution, and activated at a temperature of 80° C. for 0.5 h to obtain an activated titanium-based oxide anode plate frame, coating the surface of the activated titanium-based oxide anode plate frame with a tin-antimony precursor liquid, drying at a temperature of 100-120° C. for 8 min, and sintering pretreatment at a temperature of 400° C. for 5 min, repeating the tin-antimony precursor liquid coating and sintering process 5 times, and then sintering at a temperature of 400° C. for 1 h to obtain a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer;

(3) The drawn titanium mesh was immersed in a 10wt.% NaOH solution at 50°C for 10 min. The titanium mesh was subjected to sandblasting surface treatment and then heat treated at 400°C for 0.2 h. The titanium mesh was then placed in a 5wt.% oxalic acid solution and activated at 80°C for 0.5 h to obtain an activated titanium mesh. The surface of the activated titanium mesh was coated with a platinum-tin-antimony precursor solution, dried at 100-120°C for 8 min, and sintered at 400°C for 5 min. The platinum-tin-antimony coating was repeated 5 times. Precursor liquid and sintering process, then sintering at a temperature of 400°C for 1 hour to obtain a titanium mesh coated with Pt-Sn-SbOx; coating the surface of the titanium mesh coated with Pt-Sn-SbOx with a tin-antimony precursor liquid, drying at a temperature of 100-120°C for 8 minutes, sintering pretreatment at a temperature of 400°C for 5 minutes, repeating the coating of the tin-antimony precursor liquid and sintering process 5 times, and then sintering at a temperature of 400°C for 1 hour to obtain a titanium mesh coated with a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer;

(4) Argon arc welding a titanium mesh coated with a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer onto a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer to form a titanium-based oxide anode plate blank, wherein the titanium mesh coated with the Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer is located between adjacent titanium-clad aluminum composite rods; the titanium-based oxide anode plate blank is used as an anode and the titanium plate is used as a cathode, and is placed in a manganese nitrate composite electroplating solution, and composite electrodeposition is performed at a temperature of 80°C for 4 hours, and the titanium-based oxide anode plate is washed with deionized water and dried to obtain a titanium-based oxide anode plate; wherein the current density of the composite electrodeposition is 1A/ ^dm2 , and the stirring speed is _50rpm ; the manganese nitrate composite electroplating solution contains 40g/L manganese nitrate (Mn( _NO3 ) ₂ ), 10g/L nitric acid ( _HNO3 ), 10g/L sodium tungstate ( _Na2WO4 ), 10 g/L Ag-doped carbon fiber-β-PbO ₂ composite particles, 4 g/L Sn-Ru-TaOx coated hollow glass microspheres;

(5) welding the top of the titanium plate of the titanium-based oxide anode plate to the bottom of the titanium-clad aluminum conductive beam, and installing the insulator on the titanium-based oxide anode plate to obtain a titanium-based gradient composite manganese dioxide anode plate;

The titanium-based gradient composite manganese dioxide anode plate of this embodiment is used for non-ferrous metal (zinc) electrowinning. The zinc ion concentration in the zinc electrolyte is 50g/L, the sulfuric acid concentration is 150g/L, and the Cl ^- ion concentration is 600mg/L. Zinc electrowinning is carried out at a temperature of 40°C. The electrical efficiency of the gradient composite manganese dioxide anode plate is 3% higher than that of the traditional lead-silver (0.75wt.%) alloy anode plate, the cell voltage is reduced by 8%, the service life is extended by 1.5 times, and the cathode product 0# zinc reaches more than 99%.

Example 2: The titanium-based gradient composite manganese dioxide anode plate of this example (see Figures 1 to 4);

The titanium-clad aluminum conductive beam 1 has a length of 1200 mm, a width of 40 mm, and a height of 50 mm. The thickness of the titanium layer of the titanium-clad aluminum conductive beam 1 is 2 mm. A copper-aluminum composite conductive head 1a is welded to one end of the titanium-clad aluminum conductive beam 1. The copper-aluminum composite conductive head 1a has a length of 100 mm, a width of 36 mm, and a height of 46 mm. The titanium plate 3 has a thickness of 4 mm. The titanium-clad aluminum composite rod 4 is round, and the diameter of the round rod aluminum is The titanium layer thickness of the titanium-clad aluminum composite rod 4 is 1.5 mm, the double-layer titanium mesh 5 has a long axis of 10 mm, a short axis of 5 mm, and a cross-sectional thickness of 1.5 mm; the titanium rod 6 is a round rod, wherein the diameter of the round rod is The thickness of the metal oxide intermediate layer I is 3 μm, the thickness of the metal oxide intermediate layer II is 4 μm, and the thickness of the composite manganese dioxide active layer is 1 mm;

The metal oxide intermediate layer I is Sn-SbOx, the metal oxide intermediate layer II is a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer, and the composite manganese dioxide active layer contains Ag-doped carbon fiber-β- _PbO2 composite particles, Sn-Ru-TaOx coated hollow glass microspheres and γ- _MnO2 ; the particle size of the carbon fiber is 5μm, the particle size of the Ag-doped carbon fiber-β- _PbO2 composite particles is 50μm, and the particle size of the hollow glass microspheres is 50μm; the molar ratio of Pt, Sn and Sb in Pt-Sn-SbOx is 5:85:10, and the molar ratio of Sn and Sb in Sn-SbOx is 75:25;

Taking the mass percentage of the composite manganese dioxide active layer as 100%, the Ag-doped carbon fiber-β-PbO ₂ composite particles account for 3%, the Sn-Ru-TaOx coated hollow glass microspheres account for 0.5%, W accounts for 1.0%, and the rest is γ-MnO ₂ ; the mass percentage of Ag in the Ag-doped carbon fiber-β-PbO ₂ composite particles is 3%, the mass percentage of carbon fiber powder is 0.5%, and the rest is β-PbO ₂ ; the molar ratio of Sn, Ru and Ta in the Sn-Ru-TaOx coated hollow glass microspheres is 45:40:15, and the Sn-Ru-TaOx oxide accounts for 2% of the mass of the Sn-Ru-TaOx coated hollow glass microspheres;

The preparation method of Ag-doped carbon fiber-β- _PbO2 composite particles comprises the following specific steps:

With stainless steel as anode and titanium mesh as cathode, Ag-doped carbon fiber-β-PbO ₂ composite coating was obtained by electroplating in acidic lead nitrate composite plating solution for 6 hours, and the Ag-doped carbon fiber-β-PbO ₂ composite coating was stripped and ball-milled to an average particle size of 10 μm to obtain Ag-doped carbon fiber-β-PbO ₂ composite particles; wherein the acidic lead nitrate composite plating solution contains 150 g/L lead nitrate, 10 g/L silver nitrate, 16 g/L thiourea and 12 g/L carbon fiber particles, and the pH value of the acidic lead nitrate composite plating solution is 1; the electrodeposition temperature is 75°C, and the current density is 10 A/dm ² ;

The preparation method of Sn-Ru-TaOx coated hollow glass microspheres, the specific steps are as follows:

1) dissolving tin chloride, ruthenium chloride and tantalum chloride in concentrated hydrochloric acid, adding n-butanol solvent, and removing water by rotary evaporation to obtain a tin-ruthenium-tantalum precursor liquid;

2) calcining the hollow glass microspheres at 500° C. for 1.5 h, immersing them in a NaOH solution with a concentration of 8 wt.%, treating them at 70° C. for 20 min, washing them with deionized water, immersing them in a HF solution with a concentration of 1.2 wt.% for 3 min, washing them with deionized water, and drying them to obtain pretreated hollow glass microspheres;

3) The pretreated hollow glass microspheres were immersed in a Sn-Ru-Tantalum precursor solution for ultrasonic immersion for 8 minutes, dried at 120°C, and then calcined at 500°C for 15 minutes. The ultrasonic immersion and calcination process was repeated 10 times, and then sintered at 480°C for 2 hours to obtain Sn-Ru-TaOx coated hollow glass microsphere composite particles;

The preparation method of the titanium-based gradient composite manganese dioxide anode plate comprises the following specific steps:

(1) After degreasing and pickling, the aluminum rod is immersed in a NaOH solution with a concentration of 8 wt.%, immersed at a temperature of 60°C for 3 min, washed with deionized water, and then immersed in a _HNO3 solution with a concentration of 20 wt.% for activation for 6 min to obtain an activated aluminum rod; the inner wall of the titanium tube is treated with an HF solution with a concentration of 5 wt.%, and washed with deionized water to obtain a pretreated titanium tube; the pretreated titanium tube is sleeved outside the aluminum rod and extruded and drawn to form a composite, and hot rolled at a temperature of 600°C to obtain a titanium-clad aluminum composite rod, and the titanium-clad aluminum composite rod is welded with an aluminum-copper composite conductive head (pulse argon gas protection aluminum-aluminum welding) to obtain a titanium-clad aluminum conductive beam;

(2) welding a titanium plate, a titanium-clad aluminum composite rod and a titanium rod to form a titanium-based oxide anode plate frame, immersing the titanium-based oxide anode plate frame in a NaOH solution with a concentration of 15 wt.%, and soaking at a temperature of 60° C. for 20 min. After the titanium-based oxide anode plate frame is subjected to sandblasting surface treatment, it is heat-treated at a temperature of 600° C. for 1.0 h, and then placed in a 20 wt.% oxalic acid solution, and activated at a temperature of 100° C. for 1.0 h to obtain an activated titanium-based oxide anode plate frame, coating the surface of the activated titanium-based oxide anode plate frame with a tin-antimony precursor liquid, drying at a temperature of 120° C. for 10 min, and sintering pretreatment at a temperature of 600° C. for 8 min, repeating the tin-antimony precursor liquid coating and sintering process 7 times, and then sintering at a temperature of 550° C. for 1.5 h to obtain a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer;

(3) The drawn titanium mesh was immersed in a 15wt.% NaOH solution at 70°C for 20 min, the titanium mesh was subjected to sandblasting surface treatment, heat treated at 600°C for 1.0 h, and then placed in a 20wt.% oxalic acid solution and activated at 100°C for 1.0 h to obtain an activated titanium mesh, the surface of the activated titanium mesh was coated with a platinum-tin-antimony precursor solution, dried at 100°C for 10 min, and sintered at 600°C for 8 min, and the platinum-tin-antimony precursor solution was repeated 7 times. The titanium mesh coated with Pt-Sn-SbOx was subjected to a pretreatment process of coating the tin-antimony precursor liquid and sintering, and then sintered at a temperature of 550°C for 1.5 hours to obtain a titanium mesh coated with Pt-Sn-SbOx; a tin-antimony precursor liquid was coated on the surface of the titanium mesh coated with Pt-Sn-SbOx, dried at a temperature of 100°C for 10 minutes, and sintered at a temperature of 600°C for 8 minutes, and the coating of the tin-antimony precursor liquid and the sintering process were repeated 7 times, and then sintered at a temperature of 500°C for 1.5 hours to obtain a titanium mesh coated with a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer;

(4) Argon arc welding a titanium mesh coated with a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer onto a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer to form a titanium-based oxide anode plate blank, wherein the titanium mesh coated with the Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer is located between adjacent titanium-clad aluminum composite rods; the titanium-based oxide anode plate blank is used as an anode and the titanium plate is used as a cathode, and is placed in a manganese nitrate composite electroplating solution, and composite electrodeposition is performed at a temperature of 90°C for 10 hours, and the titanium-based oxide anode plate is washed with deionized water and dried to obtain a titanium-based oxide anode plate; wherein the current density of the composite electrodeposition is 3A/ ^dm2 , and the stirring speed is _150rpm ; the manganese nitrate composite electroplating solution contains 80g/L manganese nitrate (Mn( _NO3 ) ₂ ), 20g/L nitric acid ( _HNO3 ), 30g/L sodium tungstate ( _Na2WO4 ), 20g/L Ag-doped carbon fiber-β-PbO ₂ composite particles, 20g/L Sn-Ru-TaOx coated hollow glass microspheres;

(5) welding the top of the titanium plate of the titanium-based oxide anode plate to the bottom of the titanium-clad aluminum conductive beam, and installing the insulator on the titanium-based oxide anode plate to obtain a titanium-based gradient composite manganese dioxide anode plate;

The titanium-based gradient composite manganese dioxide anode plate of this embodiment is used for non-ferrous metal (zinc) electrowinning. The zinc ion concentration in the zinc electrolyte is 50g/L, the sulfuric acid concentration is 150g/L, and the Cl ^- ion concentration is 600mg/L. Zinc electrowinning is carried out at a temperature of 40°C. The electrical efficiency of the gradient composite manganese dioxide anode plate is 4% higher than that of the traditional lead-silver (0.75wt.%) alloy anode plate, the cell voltage is reduced by 18%, the service life is extended by 2 times, and the cathode product 0# zinc reaches more than 99%.

Embodiment 3: The titanium-based gradient composite manganese dioxide anode plate of this embodiment (see FIGS. 1 to 4 );

The titanium-clad aluminum conductive beam 1 has a length of 1300 mm, a width of 20 mm, and a height of 40 mm. The thickness of the titanium layer of the titanium-clad aluminum conductive beam 1 is 1 mm. A copper-aluminum composite conductive head 1a is welded to one end of the titanium-clad aluminum conductive beam 1. The copper-aluminum composite conductive head 1a has a length of 100 mm, a width of 18 mm, and a height of 38 mm. The thickness of the titanium plate 3 is 3 mm. The titanium-clad aluminum composite rod 4 is square, wherein the cross-sectional length of the square aluminum is 4 mm, and the width is 1 mm. The thickness of the titanium layer of the titanium-clad aluminum composite rod 4 is 0.5 mm. The long axis of the double-layer titanium mesh 5 is 3 mm, the short axis is 1 mm, and the cross-sectional thickness is 0.5 mm. The titanium rod 6 is a square rod, wherein the cross-sectional length of the square rod is 4 mm, and the width is 3 mm. The thickness of the metal oxide intermediate layer I is 1 μm, the thickness of the metal oxide intermediate layer II is 2 μm, and the thickness of the composite manganese dioxide active layer is 0.3 mm.

The metal oxide intermediate layer I is Sn-SbOx, the metal oxide intermediate layer II is a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer, and the composite manganese dioxide active layer contains Ag-doped carbon fiber-β- _PbO2 composite particles, Sn-Ru-TaOx coated hollow glass microspheres and γ- _MnO2 ; the particle size of the carbon fiber is 1μm, the particle size of the Ag-doped carbon fiber-β- _PbO2 composite particles is 10μm, and the particle size of the hollow glass microspheres is 10μm; the molar ratio of Pt, Ti, Sn and Sb in Pd-Ti-Sn-SbOx is 3:5:75:17, and the molar ratio of Sn and Sb in Sn-SbOx is 70:30;

Taking the mass percentage of the composite manganese dioxide active layer as 100%, the Ag-doped carbon fiber-β-PbO ₂ composite particles account for 1%, the Sn-Ru-TaOx coated hollow glass microspheres account for 0.5%, W accounts for 0.1%, and the rest is γ-MnO ₂ ; the mass percentage of Ag in the Ag-doped carbon fiber-β-PbO ₂ composite particles is 0.5%, the mass percentage of carbon fiber powder is 0.1%, and the rest is β-PbO ₂ ; the molar ratio of Sn, Ru and Ta in the Sn-Ru-TaOx coated hollow glass microspheres is 40:30:30, and the Sn-Ru-TaOx oxide accounts for 1% of the mass of the Sn-Ru-TaOx coated hollow glass microspheres;

The preparation method of Ag-doped carbon fiber-β- _PbO2 composite particles comprises the following specific steps:

With stainless steel as anode and titanium mesh as cathode, Ag-doped carbon fiber-β-PbO ₂ composite coating was obtained by electroplating in acidic lead nitrate composite plating solution for 4 hours, and Ag-doped carbon fiber- _{β-PbO 2 composite coating was stripped and ball-milled to obtain Ag-doped carbon fiber-β-PbO 2 composite} particles; wherein the acidic lead nitrate composite plating solution contains 50g/L lead nitrate, 0.5g/L silver nitrate, 4g/L thiourea and 4g/L carbon fiber particles, and the pH value of the acidic lead nitrate composite plating solution is; the electrodeposition temperature is 60℃, and the current density is 6A/dm ² ;

The preparation method of Sn-Ru-TaOx coated hollow glass microspheres, the specific steps are as follows:

1) dissolving tin chloride, ruthenium chloride and tantalum chloride in concentrated hydrochloric acid, adding n-butanol solvent, and removing water by rotary evaporation to obtain a tin-ruthenium-tantalum precursor liquid;

2) calcining the hollow glass microspheres at 400° C. for 0.5 h, immersing them in a 5 wt.% NaOH solution at 60° C. for 5 min, washing them with deionized water, immersing them in a 0.5 wt.% HF solution for 1 min, washing them with deionized water, and drying them to obtain pretreated hollow glass microspheres;

3) The pretreated hollow glass microspheres were immersed in a Sn-Ru-Tantalum precursor solution and ultrasonically immersed for 5 minutes, dried at 100° C., and then calcined at 300° C. for 10 minutes. The ultrasonic immersion and calcination process was repeated 6 times, and then sintered at 480° C. for 1 hour to obtain Sn-Ru-TaOx coated hollow glass microsphere composite particles;

The preparation method of the titanium-based gradient composite manganese dioxide anode plate comprises the following specific steps:

(1) After degreasing and pickling, the aluminum rod is immersed in a 5wt.% NaOH solution at 40°C for 1 min, washed with deionized water, and then immersed in a 10wt.% _HNO3 solution for activation for 4 min to obtain an activated aluminum rod; the inner wall of the titanium tube is treated with a 1wt.% HF solution and washed with deionized water to obtain a pretreated titanium tube; the pretreated titanium tube is sleeved outside the aluminum rod and extruded and drawn to obtain a composite, and hot rolled at 500°C to obtain a titanium-clad aluminum composite rod, and the titanium-clad aluminum composite rod is welded to an aluminum-copper composite conductive head (pulse argon gas protection aluminum-aluminum welding) to obtain a titanium-clad aluminum conductive beam;

(2) welding a titanium plate, a titanium-clad aluminum composite rod and a titanium rod to form a titanium-based oxide anode plate frame, immersing the titanium-based oxide anode plate frame in a NaOH solution with a concentration of 10 wt.%, and soaking it at a temperature of 50° C. for 10 min. After the titanium-based oxide anode plate frame is subjected to sandblasting surface treatment, it is heat-treated at a temperature of 400° C. for 0.2 h, and then placed in a 5 wt.% oxalic acid solution, and activated at a temperature of 80° C. for 0.5 h to obtain an activated titanium-based oxide anode plate frame, coating the surface of the activated titanium-based oxide anode plate frame with a tin-antimony precursor liquid, drying at a temperature of 120° C. for 5 min, and sintering pretreatment at a temperature of 400° C. for 5 min, repeating the tin-antimony precursor liquid coating and sintering process 3 times, and then sintering at a temperature of 400° C. for 1 h to obtain a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer;

(3) The drawn titanium mesh was immersed in a 10wt.% NaOH solution at 50°C for 10 min. The titanium mesh was subjected to sandblasting surface treatment and then heat treated at 400°C for 0.2 h. The titanium mesh was then placed in a 5wt.% oxalic acid solution and activated at 80°C for 0.5 h to obtain an activated titanium mesh. The surface of the activated titanium mesh was coated with a palladium-titanium-tin-antimony precursor solution, dried at 100-120°C for 8 min, and sintered at 400°C for 5 min. The coating of the palladium-titanium-tin-antimony precursor solution was repeated three times. and sintering process, and then sintering at a temperature of 400°C for 1 hour to obtain a titanium mesh coated with Pd-Ti-Sn-SbOx; coating a tin-antimony precursor liquid on the surface of the titanium mesh coated with Pd-Ti-Sn-SbOx, drying at a temperature of 100-120°C for 8 minutes, sintering pretreatment at a temperature of 400°C for 5 minutes, repeating the coating of the tin-antimony precursor liquid and the sintering process 3 times, and then sintering at a temperature of 400°C for 1.0 hour to obtain a titanium mesh coated with a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer;

(4) Argon arc welding a titanium mesh coated with a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer onto a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer to form a titanium-based oxide anode plate blank, wherein the titanium mesh coated with the Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer is located between adjacent titanium-clad aluminum composite rods; the titanium-based oxide anode plate blank is used as an anode and the titanium plate is used as a cathode, and is placed in a manganese nitrate composite electroplating solution, and composite electrodeposition is performed at a temperature of 80°C for 4 hours, and the titanium-based oxide anode plate is washed with deionized water and dried to obtain a titanium-based oxide anode plate; wherein the current density of the composite electrodeposition is 1A/ ^dm2 , and the stirring speed is _50rpm ; the manganese nitrate composite electroplating solution contains 20g/L manganese nitrate (Mn( _NO3 ) ₂ ), 10g/L nitric acid ( _HNO3 ), 10g/L sodium tungstate ( _Na2WO4 ), 10g/L Ag-doped carbon fiber-β-PbO ₂ composite particles, 4g/L Sn-Ru-TaOx coated hollow glass microspheres;

(5) welding the top of the titanium plate of the titanium-based oxide anode plate to the bottom of the titanium-clad aluminum conductive beam, and installing the insulator on the titanium-based oxide anode plate to obtain a titanium-based gradient composite manganese dioxide anode plate;

The titanium-based gradient composite manganese dioxide anode plate of this embodiment is used for non-ferrous metal (copper) electrowinning. The copper ion concentration in the copper electrolyte is 45g/L, the sulfuric acid concentration is 180g/L, and the Cl ^- ion is 100mg/L. Copper electrowinning is carried out at a temperature of 50°C. The electrical efficiency of the gradient composite manganese dioxide anode plate is 3% higher than that of the traditional lead-calcium (0.07wt.%)-tin (1.25wt.%) alloy anode plate, the cell voltage is reduced by 10%, the life is extended by 1 times, and the cathode product 0# zinc reaches more than 99%.

Embodiment 4: The titanium-based gradient composite manganese dioxide anode plate of this embodiment (see FIGS. 1 to 4 );

The titanium-clad aluminum conductive beam 1 has a length of 1300 mm, a width of 50 mm, and a height of 60 mm. The thickness of the titanium layer of the titanium-clad aluminum conductive beam 1 is 3 mm. A copper-aluminum composite conductive head 1a is welded to one end of the titanium-clad aluminum conductive beam 1. The copper-aluminum composite conductive head 1a has a length of 120 mm, a width of 44 mm, and a height of 54 mm. The thickness of the titanium plate 3 is 2 mm. The titanium-clad aluminum composite rod 4 is square, wherein the cross-sectional length of the square aluminum is 10 mm, and the width is 4 mm. The thickness of the titanium layer of the titanium-clad aluminum composite rod 4 is 2 mm. The double-layer titanium mesh 5 has a double-layer titanium mesh with a long axis of 16 mm, a short axis of 6 mm, and a cross-sectional thickness of 0.7 mm. The titanium rod 6 is a square rod, wherein the cross-sectional length of the square rod is 10 mm, and the width is 5 mm. The thickness of the metal oxide intermediate layer I is 5 μm, the thickness of the metal oxide intermediate layer II is 5 μm, and the thickness of the composite manganese dioxide active layer is 2 mm.

The metal oxide intermediate layer I is Sn-SbOx, the metal oxide intermediate layer II is a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer, and the composite manganese dioxide active layer contains Ag-doped carbon fiber-β- _PbO2 composite particles, Sn-Ru-TaOx coated hollow glass microspheres and γ- _MnO2 ; the particle size of the carbon fiber is 10μm, the particle size of the Ag-doped carbon fiber-β- _PbO2 composite particles is 100μm, and the particle size of the hollow glass microspheres is 100μm; the molar ratio of Pt, Sn and Sb in Pd-Ti-Sn-SbOx is 3:5:75:17, and the molar ratio of Sn and Sb in Sn-SbOx is 70:30;

Taking the mass percentage of the composite manganese dioxide active layer as 100%, the Ag-doped carbon fiber-β-PbO ₂ composite particles account for 6%, the Sn-Ru-TaOx coated hollow glass microspheres account for 4%, W accounts for 1.8%, and the rest is γ-MnO ₂ ; the mass percentage of Ag in the Ag-doped carbon fiber-β-PbO ₂ composite particles is 5%, the mass percentage of carbon fiber powder is 1%, and the rest is β-PbO ₂ ; the molar ratio of Sn, Ru and Ta in the Sn-Ru-TaOx coated hollow glass microspheres is 1:80:19, and the Sn-Ru-TaOx oxide accounts for 8% of the mass of the Sn-Ru-TaOx coated hollow glass microspheres;

The preparation method of Ag-doped carbon fiber-β- _PbO2 composite particles comprises the following specific steps:

With stainless steel as anode and titanium mesh as cathode, Ag-doped carbon fiber-β-PbO ₂ composite coating was obtained by electroplating in acidic lead nitrate composite plating solution for 8 hours, and Ag-doped carbon fiber- _{β-PbO 2 composite coating was stripped and ball-milled to obtain Ag-doped carbon fiber-β-PbO 2 composite} particles; wherein the acidic lead nitrate composite plating solution contains 150g/L lead nitrate, 20g/L silver nitrate, 20g/L thiourea and 20g/L carbon fiber particles, and the pH value of the acidic lead nitrate composite plating solution is 2; the electrodeposition temperature is 90°C, and the current density is 12A/dm ² ;

The preparation method of Sn-Ru-TaOx coated hollow glass microspheres, the specific steps are as follows:

1) dissolving tin chloride, ruthenium chloride and tantalum chloride in concentrated hydrochloric acid, adding n-butanol solvent, and removing water by rotary evaporation to obtain a tin-ruthenium-tantalum precursor liquid;

2) calcining the hollow glass microspheres at 600° C. for 2 h, immersing them in a 10 wt.% NaOH solution at 90° C. for 40 min, washing them with deionized water, immersing them in a 2 wt.% HF solution for 5 min, washing them with deionized water, and drying them to obtain pretreated hollow glass microspheres;

3) The pretreated hollow glass microspheres were immersed in a Sn-Ru-Tantalum precursor solution for ultrasonic immersion for 10 minutes, dried at 100°C, and then calcined at 560°C for 20 minutes. The ultrasonic immersion and calcination process was repeated 12 times, and then sintered at 480°C for 2 hours to obtain Sn-Ru-TaOx coated hollow glass microsphere composite particles;

The preparation method of the titanium-based gradient composite manganese dioxide anode plate comprises the following specific steps:

(1) After degreasing and pickling, the aluminum rod is immersed in a 15wt.% NaOH solution at 70°C for 5 min, washed with deionized water, and then immersed in a 40wt.% _HNO3 solution for activation for 8 min to obtain an activated aluminum rod; the inner wall of the titanium tube is treated with a 10wt.% HF solution and washed with deionized water to obtain a pretreated titanium tube; the pretreated titanium tube is sleeved outside the aluminum rod and extruded and drawn to obtain a composite, and hot rolled at 700°C to obtain a titanium-clad aluminum composite rod, and the titanium-clad aluminum composite rod is welded to an aluminum-copper composite conductive head (pulse argon gas protection aluminum-aluminum welding) to obtain a titanium-clad aluminum conductive beam;

(2) welding a titanium plate, a titanium-clad aluminum composite rod and a titanium rod to form a titanium-based oxide anode plate frame, immersing the titanium-based oxide anode plate frame in a NaOH solution with a concentration of 20 wt.%, and soaking at a temperature of 80° C. for 30 min. After the titanium-based oxide anode plate frame is subjected to sandblasting surface treatment, it is heat-treated at a temperature of 700° C. for 1.5 h, and then placed in a 30 wt.% oxalic acid solution, and activated at a temperature of 100° C. for 2.0 h to obtain an activated titanium-based oxide anode plate frame, coating the surface of the activated titanium-based oxide anode plate frame with a tin-antimony precursor liquid, drying at a temperature of 110° C. for 8 min, and sintering pretreatment at a temperature of 700° C. for 10 min, repeating the tin-antimony precursor liquid coating and sintering process 10 times, and then sintering at a temperature of 600° C. for 2 h to obtain a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer;

(3) The drawn titanium mesh was immersed in a 20wt.% NaOH solution at 80°C for 30 min, the titanium mesh was sandblasted and then heat treated at 700°C for 1.5 h, and then placed in a 30wt.% oxalic acid solution and activated at 80°C for 2.0 h to obtain an activated titanium mesh. The surface of the activated titanium mesh was coated with a palladium titanium tin antimony precursor solution, dried at 120°C for 8 min, and sintered at 600°C for 10 min. The coating of the palladium titanium tin antimony precursor was repeated 10 times. The titanium mesh coated with Pd-Ti-Sn-SbOx was subjected to a liquid and sintering process, and then sintered at a temperature of 600°C for 2 hours to obtain a titanium mesh coated with Pd-Ti-Sn-SbOx; a tin-antimony precursor liquid was coated on the surface of the titanium mesh coated with Pd-Ti-Sn-SbOx, dried at a temperature of 120°C for 8 minutes, and subjected to a sintering pretreatment at a temperature of 600°C for 10 minutes, and the tin-antimony precursor liquid coating and sintering process were repeated 10 times, and then sintered at a temperature of 600°C for 2 hours to obtain a titanium mesh coated with a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer;

(4) Argon arc welding a titanium mesh coated with a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer onto a titanium-based oxide anode plate frame coated with a metal oxide Sn-SbOx intermediate layer to form a titanium-based oxide anode plate blank, wherein the titanium mesh coated with the Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer is located between adjacent titanium-clad aluminum composite rods; the titanium-based oxide anode plate blank is used as an anode and the titanium plate is used as a cathode, and is placed in a manganese nitrate composite electroplating solution, and composite electrodeposition is performed at a temperature of 100°C for 20 hours, and the titanium-based oxide anode plate is washed with deionized water and dried to obtain a titanium-based oxide anode plate; wherein the current density of the composite electrodeposition is 5A/ ^dm2 , and the stirring speed is _300rpm ; the manganese nitrate composite electroplating solution contains 100g/L manganese nitrate (Mn( _NO3 ) ₂ ), 30g/L nitric acid ( _HNO3 ), 40g/L sodium tungstate ( _Na2WO4 ), 30 g/L Ag-doped carbon fiber-β-PbO ₂ composite particles, 30 g/L Sn-Ru-TaOx coated hollow glass microspheres;

(5) welding the top of the titanium plate of the titanium-based oxide anode plate to the bottom of the titanium-clad aluminum conductive beam, and installing the insulator on the titanium-based oxide anode plate to obtain a titanium-based gradient composite manganese dioxide anode plate;

The titanium-based gradient composite manganese dioxide anode plate of this embodiment is used for non-ferrous metal (copper) electrowinning. The copper ion concentration in the copper electrolyte is 45g/L, the sulfuric acid concentration is 180g/L, and the Cl ^- ion is 100mg/L. Copper electrowinning is carried out at a temperature of 50°C. The electrical efficiency of the gradient composite manganese dioxide anode plate is 3% higher than that of the traditional lead-calcium (0.07wt.%)-tin (1.25wt.%) alloy anode plate, the cell voltage is reduced by 15%, the life is extended by 2 times, and the cathode product 0# zinc reaches more than 99%.

The specific implementation modes of the present invention are described in detail above, but the present invention is not limited to the above implementation modes, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims (7)

1. A titanium-based gradient composite manganese dioxide anode plate is characterized in that: the titanium-coated aluminum conductive beam comprises a titanium-coated aluminum conductive beam (1) and a titanium-based oxide anode plate (2), wherein the titanium-based oxide anode plate (2) is fixedly arranged at the bottom end of the titanium-coated aluminum conductive beam (1), and an insulator (7) is arranged on the titanium-based oxide anode plate (2);

The titanium-based oxide anode plate (2) comprises a titanium plate (3), titanium-coated aluminum composite rods (4), double-layer titanium nets (5) and titanium rods (6), wherein the top ends of the titanium plate (3) are fixedly connected with the bottom ends of titanium-coated aluminum conductive beams (1), the titanium-coated aluminum composite rods (4) are vertically arranged at the bottom ends of the titanium plate (3), the titanium rods (6) are arranged at the bottom ends of the titanium-coated aluminum composite rods (4), the titanium plate (3), the titanium-coated aluminum composite rods (4) and the titanium rods (6) form a titanium-based oxide anode plate frame, the double-layer titanium nets (5) are arranged between the adjacent titanium-coated aluminum composite rods (4), the top ends of the double-layer titanium nets (5) are fixedly connected with the titanium plate (3), and the bottom ends of the double-layer titanium nets (5) are fixedly connected with the titanium rods (6); the titanium surface of the titanium-based oxide anode plate frame is sequentially coated with a metal oxide intermediate layer I and a composite manganese dioxide active layer, and the titanium surface of the double-layer titanium mesh (5) is sequentially coated with a metal oxide intermediate layer II and a composite manganese dioxide active layer;

The metal oxide intermediate layer I is Sn-SbOx, the metal oxide intermediate layer II is a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer, and the composite manganese dioxide active layer contains Ag-carbon fiber-beta-PbO ₂ doped composite particles, sn-Ru-TaOx coated hollow glass beads and gamma-MnO ₂;

The mol ratio of Pt, sn and Sb in the Pt-Sn-SbOx is 1-7:80-87:6-19, the mol ratio of Pd, ti, sn and Sb in the Pd-Ti-Sn-SbOx is 1-5:3-8:70-85:2-24, and the mol ratio of Sn and Sb in the Sn-SbOx is 70-80:20-30;

The mass percentage of the composite manganese dioxide active layer is 100 percent, the composite particles of the Ag-doped carbon fiber-beta-PbO ₂ account for 1 to 6 percent, the Sn-Ru-TaOx coated hollow glass beads account for 0.5 to 4 percent, the W accounts for 0.05 to 2 percent, and the balance is gamma-MnO ₂; the Ag-carbon fiber-beta-PbO ₂ composite particles comprise 0.5-5% of Ag, 0.1-1% of carbon fiber powder and the balance of beta-PbO ₂; the molar ratio of Sn, ru and Ta in the Sn-Ru-TaOx coated hollow glass microsphere is 40-50:30-42:8-30, and the Sn-Ru-TaOx oxide accounts for 1-8% of the mass of the Sn-Ru-TaOx coated hollow glass microsphere.

2. The titanium-based gradient composite manganese dioxide anode plate of claim 1, wherein: the thickness of the titanium layer of the titanium-coated aluminum conductive beam (1) is 1-3 mm, one end of the titanium-coated aluminum conductive beam (1) is welded with a copper-aluminum composite conductive head, the thickness of a titanium plate (3) is 3-5 mm, the thickness of the titanium layer of the titanium-coated aluminum composite rod (4) is 0.5-2 mm, the long axis of a double-layer titanium mesh of the double-layer titanium mesh (5) is 3-16 mm, the short axis is 1-6 mm, and the section thickness is 0.5-3 mm; the thicknesses of the metal oxide intermediate layer I and the metal oxide intermediate layer II are 1-5 mu m, and the thickness of the composite manganese dioxide active layer is 0.3-2 mm.

3. The titanium-based gradient composite manganese dioxide anode plate of claim 1, wherein: the granularity of the carbon fiber is 1-10 mu m, the granularity of the Ag-carbon fiber-beta-PbO ₂ doped composite particle is 10-100 mu m, and the granularity of the hollow glass bead is 10-100 mu m.

4. The titanium-based gradient composite manganese dioxide anode plate of claim 1, wherein: the preparation method of the Ag-carbon fiber-beta-PbO ₂ -doped composite particle comprises the following specific steps:

Electrodepositing stainless steel serving as an anode and a titanium mesh serving as a cathode in an acidic lead nitrate composite plating solution for 4-8 hours to obtain an Ag-doped carbon fiber-beta-PbO ₂ composite plating layer, stripping the Ag-doped carbon fiber-beta-PbO ₂ composite plating layer, and performing ball milling to obtain Ag-doped carbon fiber-beta-PbO ₂ composite particles; the acidic lead nitrate composite plating solution contains 50-200 g/L of lead nitrate, 0.5-20 g/L of silver nitrate, 4-20 g/L of thiourea and 4-20 g/L of carbon fiber particles, and the pH value of the acidic lead nitrate composite plating solution is 0-2; the temperature of the electrodeposition is 60-90 ℃, and the current density is 6-12A/dm ².

5. The titanium-based gradient composite manganese dioxide anode plate of claim 1, wherein: the preparation method of the Sn-Ru-TaOx coated hollow glass microsphere comprises the following specific steps:

1) Dissolving tin chloride, ruthenium chloride and tantalum chloride in concentrated hydrochloric acid, adding n-butanol solvent, and removing water by rotary evaporation to obtain tin ruthenium tantalum precursor liquid;

2) Calcining the hollow glass beads at 400-600 ℃ for 0.5-2 h, immersing in a NaOH solution with the concentration of 5-10 wt.%, treating at 60-90 ℃ for 5-40 min, immersing in an HF solution with the concentration of 0.5-2 wt.% for 1-5 min after washing with deionized water, performing deionized washing, and drying to obtain pretreated hollow glass beads;

3) Immersing the pretreated hollow glass beads in tin-ruthenium-tantalum precursor liquid for 5-10 min, drying, roasting at 300-560 ℃ for 10-20 min, repeating the ultrasonic immersing and roasting processes for 6-12 times, and sintering at 400-480 ℃ for 1-2 h to obtain the Sn-Ru-TaOx coated hollow glass bead composite particles.

6. The method for preparing the titanium-based gradient composite manganese dioxide anode plate according to any one of claims 1 to 5, which is characterized in that: the method comprises the following specific steps:

(1) Immersing the aluminum bar into NaOH solution for 1-5 min after degreasing and pickling, cleaning by deionized water, and immersing into HNO ₃ solution for activation for 4-8 min to obtain an activated aluminum bar; the inner wall of the titanium tube is treated by HF solution, and is cleaned by deionized water to obtain a pretreated titanium tube; the pretreated titanium tube is sleeved outside the aluminum rod and is extruded, drawn and compounded, the titanium-coated aluminum composite rod is obtained through hot rolling, and the titanium-coated aluminum composite rod and the aluminum-copper composite conductive head are welded to obtain a titanium-coated aluminum conductive beam;

(2) Welding a titanium plate, a titanium-coated aluminum composite rod and a titanium rod to form a titanium-based oxide anode plate frame, immersing the titanium-based oxide anode plate frame in a NaOH solution for 10-30 min, performing heat treatment on the titanium-based oxide anode plate frame after sand blasting surface treatment, then placing the titanium-based oxide anode plate frame in an oxalic acid solution for activating for 0.5-2.0 h to obtain an activated titanium-based oxide anode plate frame, coating tin-antimony precursor liquid on the surface of the activated titanium-based oxide anode plate frame, drying, performing sintering pretreatment for 5-10 min, repeating the steps of coating tin-antimony precursor liquid and sintering for 3-10 times, and then placing the titanium-based oxide anode plate frame coated with a metal oxide intermediate layer at the temperature of 400-600 ℃ for sintering for 1-2 h to obtain the titanium-based oxide anode plate frame coated with the metal oxide intermediate layer;

(3) Immersing a drawn titanium mesh in a NaOH solution for 10-30 min, performing heat treatment after performing sand blasting surface treatment on the titanium mesh, then placing the titanium mesh in an oxalic acid solution for activation for 0.5-2.0 h to obtain an activated titanium mesh, coating platinum tin antimony precursor liquid or palladium titanium tin antimony precursor liquid on the surface of the activated titanium mesh, drying, performing sintering pretreatment for 5-10 min, repeating the coating and sintering processes for 3-10 times, and then placing the titanium mesh at 400-600 ℃ for sintering for 1-2 h to obtain a titanium mesh coated with Pt-Sn-SbOx or Pd-Ti-Sn-Sb; coating tin-antimony precursor liquid on the surface of the titanium mesh coated with Pt-Sn-SbOx or Pd-Ti-Sn-Sb, drying, then sintering and pre-treating for 5-10 min, repeating the steps of coating tin-antimony precursor liquid and sintering for 3-5 times, and then sintering for 1-2 h at the temperature of 400-600 ℃ to obtain the titanium mesh coated with the Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer;

(4) Welding a titanium mesh coated with a Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or a Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer on a titanium-based oxide anode plate frame coated with a metal oxide intermediate layer to form a titanium-based oxide anode plate blank, wherein the titanium mesh coated with the Pt-Sn-SbOx/Sn-SbOx oxide intermediate layer or the Pd-Ti-Sn-SbOx/Sn-SbOx oxide intermediate layer is positioned between adjacent titanium-clad aluminum composite rods; placing a titanium-based oxide anode plate blank serving as an anode and a titanium plate serving as a cathode in a manganese nitrate composite electroplating solution for composite electrodeposition, cleaning with deionized water, and drying to obtain a titanium-based oxide anode plate;

(5) And welding the top end of a titanium plate of the titanium-based oxide anode plate to the bottom end of a titanium-coated aluminum conductive beam, and mounting an insulator on the titanium-based oxide anode plate to obtain the titanium-based gradient composite manganese dioxide anode plate.

7. The method for preparing the titanium-based gradient composite manganese dioxide anode plate according to claim 6, wherein the method comprises the following steps: the method comprises the steps of (1) 5-10wt.% of NaOH solution, 40-70 ℃ of NaOH solution soaking temperature, 10-40 wt.% of HNO ₃ solution, 1-10wt.% of HF solution, 500-700 ℃ of hot rolling temperature and pulse argon protection aluminum-aluminum welding;

the concentration of the NaOH solution is 10-20wt%, the soaking temperature of the NaOH solution is 50-80 ℃, the heat treatment temperature is 400-700 ℃, the heat treatment time is 0.2-1.5 h, the concentration of the oxalic acid solution is 5-30wt%, the activation temperature is 80-100 ℃, and the sintering pretreatment temperature is 400-700 ℃;

The concentration of the NaOH solution is 10-20wt%, the soaking temperature of the NaOH solution is 50-80 ℃, the heat treatment temperature is 400-700 ℃, the heat treatment time is 0.2-1.5 h, the concentration of the oxalic acid solution is 5-30wt%, the activation temperature is 80-100 ℃, and the sintering pretreatment temperature is 400-700 ℃;

The temperature of the composite electrodeposition in the step (4) is 80-100 ℃, the current density is 1-5A/dm ², the stirring speed is 50-300 rpm, and the composite electrodeposition time is 4-20 h; the manganese nitrate composite plating solution contains 20-100 g/L manganese nitrate, 2-30 g/L nitric acid, 10-40 g/L sodium tungstate, 10-30 g/L Ag-doped carbon fiber-beta-PbO ₂ composite particles and 4-30 g/L Sn-Ru-TaOx coated hollow glass microspheres.