阅读说明：本技术 一种电解铝用析铝析氧电极及其制备方法 (Aluminum-separating oxygen-evolution electrode for electrolytic aluminum and preparation method thereof ) 是由 李超勇 娄世彬 杨子杰 李正贵 于 2021-11-19 设计创作，主要内容包括：本发明公开了一种电解铝用析铝析氧电极,包括导杆和基体,所述导杆与所述基体为一体成型结构；所述导杆和所述基体由复合催化剂和六方氮化硼按照体积比4～8:3～4制备组成。本申请通过复合催化剂与六方氮化硼按照一定体积制备形成高导热导电电极,电极表面形成的BN一体化3Ni2CoMoO-(9)氧化膜也能导电,做阳极能析氧,做阴极能析铝,阴阳两极可以交替使用,性价比高,且可低成本运行。(The invention discloses an aluminum precipitation oxygen evolution electrode for electrolytic aluminum, which comprises a guide rod and a substrate, wherein the guide rod and the substrate are of an integrally formed structure; the guide rod and the matrix are prepared from a composite catalyst and hexagonal boron nitride according to a volume ratio of 4-8: 3-4. The high-heat-conductivity and electric-conduction electrode is prepared from the composite catalyst and the hexagonal boron nitride according to a certain volume, and the BN integrated 3Ni2CoMoO formed on the surface of the electrode 9 The oxide film can also conduct electricity, can generate oxygen when used as an anode, can generate aluminum when used as a cathode, can be used alternately with a positive pole and a negative pole, has high cost performance, and can operate at low cost.)

1. An aluminum-separating oxygen-evolution electrode for electrolytic aluminum is characterized by comprising a guide rod and a substrate, wherein the guide rod and the substrate are of an integrally formed structure; the guide rod and the matrix are prepared from a composite catalyst and hexagonal boron nitride according to a volume ratio of 4-8: 3-4.

2. The aluminum electrolysis oxygen evolution electrode according to claim 1, wherein the composite catalyst and the hexagonal boron nitride are prepared in a volume ratio of 5: 3.

3. The aluminum electrolysis oxygen evolution electrode according to claim 1, wherein the composite catalyst and the hexagonal boron nitride are prepared in a volume ratio of 6: 4.

4. The aluminum electrolysis oxygen evolution electrode according to claim 1, wherein the composite catalyst and the hexagonal boron nitride are prepared in a volume ratio of 7: 3.

5. The alumite electrode for electrolytic aluminum according to any one of claims 1 to 4, wherein the composite catalyst comprises Mo, Co and Ni, and the molecular ratio of the elements Mo, Co and Ni is 1:2: 3.

6. The method for preparing an aluminum-evolving oxygen-evolving electrode for electrolyzing aluminum according to claim 1, comprising the steps of: the composite catalyst and the hexagonal boron nitride are mixed according to the volume ratio of 4-8: 3-4 and then subjected to cold pressing treatment, the cold-pressed material is subjected to rotary swaging forming, and the preliminarily formed material is subjected to roasting, hot pressing and finally rotary swaging forming again.

7. The method for preparing an aluminum electrolysis oxygen evolution electrode according to claim 6, wherein the cold pressing and the hot pressing are performed on a substrate, and the conductor is formed by swaging.

Technical Field

The invention relates to the field of electrolytic aluminum industry, in particular to an aluminum precipitation oxygen evolution electrode for electrolytic aluminum and a preparation method thereof.

Background

The production of the metal aluminum adopts a molten salt electrolysis electrolytic bath, and the process is as follows: electrolyte Al₂O₃Cryolite (Na)₃AlF₆) And other fluoride salts, inserting carbon cathode and anode, introducing direct current, performing electrochemical reaction to obtain liquid aluminum at cathode and O at anode₂Anodic oxidation with carbon to form CO₂. And pumping out the aluminum liquid by using a vacuum bag, purifying and clarifying, and sintering to generate an aluminum ingot.

And (3) electrifying with strong direct current:

cathode: al (Al)³⁺(Complex) +3e → Al

Anode: 2O^2-+C-4e→CO₂

In total: 2Al₂O₃+3e→4Al+3CO₂

During the electrolysis process, the carbon anode is continuously consumed, and the temperature of the electrolytic cell can be adjusted only by adjusting the polar distance in time.

At present, carbon dioxide generated in the electrolytic aluminum industry in the electrolytic process accounts for lower total carbon emission in China, but with the establishment of the whole carbon emission target, the carbon emission control of the electrolytic aluminum industry is urgent, so how to control the carbon emission of electrolytic aluminum also becomes the research and development direction of the industry; in addition, some enterprises develop inert anodes aiming at the problem of continuous consumption of carbon anodes, for example, an inert alloy anode for aluminum electrolysis and a preparation method (CN10348495A) thereof disclose an inert alloy anode, which solves the problems of cost, overvoltage and oxide film falling, but the connection electrode in the application process is not resistant to high temperature and affects the normal production and operation of the electrolytic cell.

Disclosure of Invention

The application provides an aluminum precipitation oxygen evolution electrode for electrolytic aluminum and a preparation method thereof, and the electrode material is applied to the production of electrolytic aluminum, can reduce energy consumption and reduce the emission of greenhouse gases, and simultaneously has a series of characteristics of high conductivity, high strength, high temperature resistance, strong corrosion resistance, difficult dissolution in electrolyte and the like.

In order to achieve the purpose, the invention discloses the following technical scheme:

the application discloses an aluminum precipitation oxygen evolution electrode for electrolytic aluminum, which comprises a guide rod and a base body, wherein the guide rod and the base body are of an integrally formed structure; the guide rod and the matrix are prepared from a composite catalyst and hexagonal boron nitride according to a volume ratio of 4-8: 3-4.

The high-heat-conductivity and electric-conduction electrode is prepared from the composite catalyst and the hexagonal boron nitride according to a certain volume, and the BN integrated 3Ni2CoMoO formed on the surface of the electrode₉The oxide film can also conduct electricity, can generate oxygen when used as an anode, can generate aluminum when used as a cathode, can be used alternately with a positive pole and a negative pole, has high cost performance, and can operate at low cost.

Preferably, the composite catalyst and the hexagonal boron nitride are prepared in a volume ratio of 5: 3.

Preferably, the composite catalyst and the hexagonal boron nitride are prepared in a volume ratio of 6: 4.

Preferably, the composite catalyst and the hexagonal boron nitride are prepared in a volume ratio of 7: 3.

Preferably, the composite catalyst consists of Mo, Co and Ni, and the molecular ratio of the elements Mo, Co and Ni is 1:2: 3.

The application also discloses a preparation method of the aluminum-separating oxygen-evolution electrode for electrolyzing aluminum, which comprises the following steps:

the composite catalyst and the hexagonal boron nitride are mixed according to the volume ratio of 4-8: 3-4 and then subjected to cold pressing treatment, the cold-pressed material is subjected to rotary swaging forming, and the preliminarily formed material is subjected to roasting, hot pressing and finally rotary swaging forming again.

Preferably, the cold pressing and the hot pressing are basal bodies, and the conductor is formed by rotary swaging.

Mo, Co and Ni are used as catalysts, hexagonal boron nitride BN is used as a carrier, and the molecular ratio of Mo, Co and Ni elements is 1:2:3 and is fixed. The volume ratio of BN to Mo, Co and Ni can be adjusted to be in a proper range for molding, the heat conduction and the electric conduction are both considered, such as 4:6 or 3:7, and the molding is carried out by cold pressing, rotary swaging molding, roasting, hot pressing and rotary swaging molding, wherein the cold and hot pressing is used as a base body, and the rotary swaging is used as a connecting guide rod. The guide rod and the substrate are an organic whole of the aluminum precipitation oxygen evolution electrode, and the defect is that the aluminum precipitation oxygen evolution electrode cannot be used.

Detailed Description

The application discloses electrolytic aluminum is with separating out aluminium oxygen evolution electrode, including guide arm and base member, the guide arm with the base member is the integrated into one piece structure, the guide arm with the base member has composite catalyst and hexagonal boron nitride according to volume ratio 4 ~ 8: 3-4, preparing a composite catalyst, wherein the composite catalyst consists of Mo, Co and Ni, the molecular ratio of the Mo, Co and Ni elements is 1:2:3, preparing a high-heat-conductivity and high-electric-conductivity electrode by the composite catalyst and hexagonal boron nitride according to a certain volume, and forming a BN integrated 3Ni2CoMoO on the surface of the electrode₉The oxide film can also conduct electricity, can generate oxygen when used as an anode, can generate aluminum when used as a cathode, can be used alternately with a positive pole and a negative pole, has high cost performance, and can operate at low cost.

The application also provides a preparation method of the aluminum-separating oxygen-evolution electrode for electrolyzing aluminum, which comprises the following steps: the composite catalyst and the hexagonal boron nitride are mixed according to the volume ratio of 4-8: 3-4 and then subjected to cold pressing treatment, the cold-pressed material is subjected to rotary swaging forming, the preliminarily formed material is subjected to roasting and hot pressing in sequence and finally subjected to rotary swaging forming again, Mo, Co and Ni are used as catalysts, hexagonal boron nitride BN is used as a carrier, and the molecular ratio of Mo, Co and Ni elements is constant at 1:2: 3. The volume ratio of BN to Mo, Co and Ni can be adjusted to be in a proper range for molding, the heat conduction and the electric conduction are both considered, such as 4:6 or 3:7, and the molding is carried out by cold pressing, rotary swaging molding, roasting, hot pressing and rotary swaging molding, wherein the cold and hot pressing is used as a base body, and the rotary swaging is used as a connecting guide rod. The guide rod and the substrate are an organic whole of the aluminum precipitation oxygen evolution electrode, and the defect is that the aluminum precipitation oxygen evolution electrode cannot be used.

Example one

The embodiment of the application discloses an aluminum-precipitation oxygen-evolution electrode for electrolytic aluminum, wherein the molecular ratio of Mo, Co and Ni elements is 1:2:3, the volume ratio of the Mo, Co and Ni elements to hexagonal Boron Nitride (BN) is 5:3, one part of the Mo, Co and Ni elements is used as a matrix through cold and hot pressing according to the requirements of an electrolytic cell, the other part of the Mo, Co and Ni elements is used as a guide rod through rotary swaging forming, and a complete aluminum-precipitation oxygen-evolution electrode product is formed through roasting, wherein the density of the aluminum-precipitation oxygen-evolution electrode product is 6.8g/cm³The specific resistance was 85. mu.Q.cm, and the melting point was 1450 ℃.

Example two

The embodiment of the application discloses an aluminum-precipitation oxygen-evolution electrode for electrolytic aluminum, wherein the molecular ratio of Mo, Co and Ni elements is 1:2:3, the volume ratio of the Mo, Co and Ni elements to hexagonal Boron Nitride (BN) is 6:4, one part of the Mo, Co and Ni elements is used as a matrix through cold and hot pressing according to the requirements of an electrolytic cell, the other part of the Mo, Co and Ni elements is used as a guide rod through rotary swaging forming, and a complete aluminum-precipitation oxygen-evolution electrode product is formed through roasting, wherein the density of the aluminum-precipitation oxygen-evolution electrode product is 6.8g/cm³The specific resistance was 90. mu.Q.cm, and the melting point was 1550 ℃.

EXAMPLE III

The embodiment of the application discloses an aluminum precipitation oxygen evolution electrode for electrolytic aluminum, wherein the molecular ratio of Mo, Co and Ni elements is 1:2:3, the volume ratio of the Mo, Co and Ni elements to hexagonal boron nitride BN is 7:3, one part of the Mo, Co and Ni elements is used as a matrix through cold and hot pressing according to the requirements of an electrolytic cell, the other part of the Mo, Co and Ni elements is used as a guide rod through rotary swaging forming, and a complete aluminum precipitation oxygen evolution electrode product is formed through roasting, wherein the density is 7.3g/cm3, the specific resistance is 82 mu Q & cm, and the melting point is 1500 ℃.

Example four

The practical application test of the electrolytic experimental tank is enlarged, and the cathode and the anode are vertically inserted into the electrolytic tank with the corundum lining, and the polar distance is 2 cm. At 760 ℃, the anode current density is 2.2A/cm²Cryolite electrolysis was carried out for up to 40 hours in cryolite electrolyte and the test results are given in the table below.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed.