CN103774180A - Device and method for preparing metal and alloy through integration of chlorination and electrolysis - Google Patents

Abstract

A device and method for producing metals and alloys integrating chlorination and electrolysis. The top of the shell is provided with an upper cover; the graphite anode and the graphite anode cover are fixed together on the cathode; The hole communicates the material chamber with the outside of the graphite anode; the anode guide rod is provided with a feeding channel to communicate with the material chamber. The method is: press the metal oxide powder and carbon powder into pellets and put them into the material chamber; put the electrolyte in the electrolysis device, and conduct electrolysis with the current density of 0.3~6.0A/cm ² and the temperature of 700~1000℃; A metal or alloy is formed on the surface of the cathode. The method of the present invention enables the two processes of chlorination and electrolysis of metal oxides to be carried out and completed in the same electrolysis device, which has the advantages of saving floor space and reducing production costs, and has the advantages of simple and convenient operation and is suitable for large-scale industrial production. Effect.

Description

A device and method for producing metals and alloys integrating chlorination and electrolysis

technical field

The invention belongs to the technical field of metallurgy, and in particular relates to a device and method for preparing metals and alloys integrating chlorination and electrolysis.

Background technique

In the non-ferrous metal industry, some metals or alloys are produced by molten salt electrolysis of the metal chloride, or are produced by reducing the chloride of the metal with a metal that is more active than the metal as a reducing agent.

Taking the metallurgical method of metal titanium as an example, the current industrial production method of titanium is the Kroll method, that is, the magnesium thermal reduction process. The process flow of the method is as follows: first chlorinate the raw material containing TiO ₂ to produce TiCl ₄ , then purify and remove impurities from the produced TiCl ₄ , and then reduce it with magnesium steam to obtain sponge titanium and anhydrous MgCl ₂ ; Due to the disadvantages of many processes and non-continuous production, high energy consumption, large environmental pollution and serious equipment corrosion, the production cost of titanium is high, which seriously restricts the application of titanium metal in wider fields.

Using TiCl ₄ as raw material to produce metal titanium by molten salt electrolysis with an electrolyte system of chloride has the advantages of low cost and easy separation of electrolyte and product; the traditional TiCl ₄ electrolysis production of metal titanium needs to use a set of equipment to convert TiO ₂ with chlorine gas chlorine To prepare pure TiCl ₄ by chemical method, and then carry out the electrolysis of TiCl ₄ , but there are still many difficulties that cannot be overcome in the molten salt electrolysis method using TiCl ₄ as raw material, such as the composition of the electrolyte fluctuates greatly during the electrolysis process, and the materials in the electrolysis process The balance is difficult to control, the densification of the generated titanium layer affects the precipitation of metal titanium in the later stage, and the electrolytic cell is severely corroded. These shortcomings seriously restrict the industrial application of TiCl ₄ molten salt electrolysis.

Taking rare earth metal chloride molten salt electrolysis to produce rare earth alloys as an example, the theory and industrial production practice of molten salt electrolysis show that many rare earth metals and rare earth metal alloys can be produced by molten salt electrolysis, but the chlorides of rare earth metals are mostly They are all prepared by the reaction of metal oxides and hydrochloric acid, or by chlorination of the mixture of metal oxides and carbon at high temperature by chlorine gas. The process is complicated and the production process not only produces waste water, Exhaust gas or waste residue also increases production costs.

Some rare earth metals with high melting points are produced by metallothermic reduction of relatively active metals such as calcium at high temperatures. It is also complicated and difficult to separate these rare earth metals from the products of the reduction reaction; aluminum is It is produced by melting oxides as raw materials in cryolite electrolyte melt and using molten salt electrolysis. In the molten salt electrolysis of cryolite-alumina, not only alumina but also carbon anode are consumed to produce one ton Metal aluminum needs to consume about 0.5 tons of carbon anode. The production of carbon anode is a complex process with high production cost; in addition, the anode of the aluminum electrolytic cell and the electrolyte melt have high resistance, and the voltage drop of the anode and the electrolyte are high, so people have been exploring and developing The technology of producing metal aluminum by electrolysis of aluminum chloride molten salt.

However, since aluminum chloride is a gaseous compound at high temperature, and anhydrous aluminum chloride is produced by chlorine chlorination of aluminum oxide at high temperature, the production and transportation of aluminum chloride And it is very difficult to keep the material balance in the electrolyzer, which leads to the method of producing metal aluminum by electrolysis of anhydrous aluminum chloride chloride molten salt, which has not been industrially successful.

Contents of the invention

Aiming at the above-mentioned problems existing in the preparation process of existing metals or alloys, the present invention provides a device and method for preparing metals and alloys integrating chlorination and electrolysis, so that the two processes of chlorination and electrolysis of metal oxides It is carried out and completed in the same electrolysis device, no need for another set of devices to prepare metal chlorides, and at the same time solves the material balance problem of metal compounds in the electrolysis process.

A device for producing metals and alloys integrating chlorination and electrolysis of the present invention includes an electrolytic cell device, thermal insulation material, electrolytic cell lining, cathode, conductor, cathode steel rod, graphite anode, graphite anode cover and anode The guide rod, the device shell and the cover on the upper part of the shell, the upper cover is provided with a vacuum suction pipe port, a gas exchange port and a thermocouple tube interface, and a sealing port that can be inserted into the vacuum suction pipe for suctioning the liquid metal and electrolyte melt of the cathode, Above the cathode is a graphite anode, the graphite anode has an upper cover, and the anode guide rod is fixed and sealed with the anode cover; there is a material chamber inside the graphite anode, and a side hole is provided on the side wall of the material chamber to communicate the material chamber with the graphite anode; the anode There is a feeding channel in the guide rod to communicate with the material chamber; the working surface of the graphite anode is a conical concave surface with a high middle and a low outer edge, and a graphite gas collection pipe is provided at the highest point, and pores are provided on the side wall of the graphite gas collection pipe to make the graphite gas collection pipe The interior communicates with the material chamber; the cathode working surface is a conical surface with a high middle and a low outer edge.

The shell of the whole device is made of stainless steel plate. The upper part of the electrolytic cell is located on the inner wall of the device shell with a crystallizer made of stainless steel, or a protective layer made of graphite material. There is a cooling water jacket outside the shell in contact with the crystallizer. .

The distance between the cathode working surface and the graphite anode working surface in the above device is 4-20 cm.

The upper part of the electrolytic cell is provided with a perforated heat shield, the anode guide rod passes through the heat shield, and the thermocouple tube and the vacuum suction pipe can also pass through the heat shield.

The above-mentioned graphite anode working surface is provided with grooves with a depth of 2-10 mm.

The top of the above-mentioned graphite gas collecting pipe is closed, and the bottom opening communicates with the groove on the working surface of the graphite anode.

The above-mentioned anode guide rod is composed of the outer wall of the guide rod and the inner lining of the guide rod. The tube hole formed by the inner lining of the anode guide rod is used as a feeding channel, and the top of the feeding channel is provided with a feeding cover; the material of the outer wall of the guide rod is steel, and the material of the inner lining of the anode guide rod is It is made of refractory material or graphite; the outer wall of the guide rod is sealed and fixed with the graphite anode cover.

The above-mentioned device is provided with at least one set of graphite anode and cathode.

The above cathode is made of iron, or tungsten, or molybdenum, or carbonaceous material, or TiB ₂ -TiC composite material, or TiB ₂ -C composite material.

The above-mentioned refractory materials are made of alumina corundum, magnesia-aluminum spinel, fused magnesia brick, magnesium oxide or calcium oxide, or metal oxide materials ready for electrolysis.

Graphite is selected as the above-mentioned carbonaceous material.

Each point on the above-mentioned cathode working surface is equidistant from the anode.

The above-mentioned graphite anode working surface is the bottom surface of the graphite anode, and the cathode working surface is the top surface of the cathode.

At least one set of cathodes and anodes is provided in the above-mentioned electrolysis device integrating chlorination-electrolysis for producing metals or alloys.

A kind of electrolysis method of producing metal or alloy that integrates chlorination-electrolysis of the present invention is to adopt above-mentioned device, carry out according to the following steps:

1. Prepare metal oxide powder and carbon powder with a particle size of 80-200 mesh. The ratio of carbon powder and metal oxide powder is prepared according to complete reaction and excess carbon powder 0-10%. The reaction formula based on complete reaction is

M _x O _y +yC=xM+yCO; (1)

The metal oxide M _x O _y is MgO, rare metal oxides such as TiO ₂ and V ₂ O ₃ , rare earth metal oxides such as lanthanum and cerium, and third main group metal oxides such as aluminum, boron, gallium and indium. One or both, x is 1 or 2, y is 1, 2 or 3;

2. Mix the metal oxide and carbon powder evenly and press them into pellets;

3. Put the electrolyte in the electrolytic cell and the material chamber in the anode, then lower the working surface of the anode to the working surface of the cathode, and use the inter-electrode arc resistance to start the roasting of the electrolytic cell;

4. Vacuum the electrolytic cell to a vacuum degree ≤ 100Pa, and then pass inert gas into the electrolytic cell to normal pressure;

5. After the electrolyte melts and reaches the electrolysis temperature of 700-900°C, replenish the electrolyte through the feeding channel in the middle of the anode guide rod, so that the height of the electrolyte melt is higher than the upper surface of the anode, and then lift the anode to make the electrode spacing equal to 4-15cm. After that, electrify the graphite anode and cathode for electrolysis. During electrolysis, control the liquid level of the molten electrolyte to be higher than the side hole, and then add pellets to the material chamber through the feeding channel in the anode guide rod, so that the height of the material in the material chamber is high. in the side holes and pores; the current density of the graphite anode is 0.3~6.0A/cm ² , and the electrolysis temperature is 700~1000°C; when the metal oxide powder is a kind of metal oxide in the preparation of pellets, it will be formed on the surface of the cathode Metal; when the metal oxide powder in the preparation of pellets is two metal oxides, an alloy is formed on the surface of the cathode.

In the above method, when the prepared metal oxides are two metal oxides, the ratio of the two metal oxides is determined according to the target alloy composition.

The weight content of KCl in the above electrolyte components is 50-100%, and the remaining components are one or two of NaCl, LiCl, MgCl ₂ , BaCl ₂ and CaCl ₂ .

In the above method, when the metal oxide and carbon powder are uniformly mixed and pressed into pellets, a binder is added or not added to the metal oxide and carbon powder; the binder is selected from resin, tar or pitch; when When no binder is added, the metal oxide and carbon powder are mixed evenly and then pressed into pellets under the pressure of 10~100MPa; when the binder is added, the metal oxide, carbon powder and binder are first mixed evenly Finally, press it into a sphere at a temperature of 20-200°C and a pressure of 10-100MPa, then cover the sphere with carbon powder to isolate it from the air, and then roast it at a temperature of 500-600°C for 2-10 hours to make a pellet .

The above-mentioned carbon powder is calcined petroleum coke powder, wherein the weight content of C is ≥ 95%.

In the electrolysis process of the above method, the anode gas _Cl2 produced on the graphite anode working surface moves along the groove to the top of the graphite anode working surface, then enters the graphite gas collector, then enters the material chamber through the pores, and is oxidized with the metal in the material chamber. The metal chloride and carbon powder react to form metal chloride and CO; CO escapes into the molten electrolyte melt through the side hole of the material chamber, and during this process, CO carries metal chloride into the molten electrolyte outside the material chamber, and at the same time The Cl ₂ generated on the bottom surface of the graphite anode moves upward along the bottom surface of the carbon anode and enters the gas collector and enters the material chamber, so that the metal chloride and the molten electrolyte enter the space between the graphite anode and the cathode from the outside surface of the graphite anode downward, and in this space The electrolysis reaction is carried out, and the metal cations are electrolytically reduced to metal particles at the cathode to form metals or alloys.

When the electrolysis product of the cathode is liquid metal or liquid alloy or metal powder and it is collected into the groove around the cathode, the cathode product can be sucked into the vacuum bag by using a vacuum suction tube inserted from the upper cover of the device. The whole process For continuous production process.

When the cathode product is a solid needle-like or spongy metal product or metal, the electrolysis process is an intermittent electrolysis process. After a period of electrolysis, when the dendrite or spongy product of the cathode product has large unevenness When the electrolysis is stopped, the anode is lowered to the surface of the cathode, and the anode is rotated to flatten the cathode product. Then lift the anode and keep the original pole distance to continue electrolysis. After repeating the process many times in this way, the anode continues to rise, and the electrolytic product accumulates thicker and thicker. When it reaches a certain thickness, stop electrolysis. Use the straw inserted from the upper cover of the device to suck the electrolyte into the vacuum ladle, and then vacuum distill the electrolyte remaining in the cathode product to the crystallizer. After the electrolytic cell in the device cools down to room temperature, open the upper cover and take it out electrolyte.

The method of the present invention enables the two processes of chlorination and electrolysis of metal oxides to be carried out and completed in the same electrolysis device, which has the advantages of saving floor space and reducing production costs, and has the advantages of simple and convenient operation and is suitable for large-scale industrial production. Effect.

Description of drawings

Fig. 1 is the schematic diagram of the structure of an electrolysis device for producing metals or alloys using metal oxides as raw materials in Example 1 of the present invention;

In the figure, 1. Graphite anode, 2. Material chamber, 3. Cathode, 4. Conductor, 5. Cathode steel rod, 6. Upper cover, 7. Thermocouple tube, 8. Ventilation port, 9. Feeding cover, 10. Vacuum suction pipe mouth, 11. Cooling water jacket, 12. Outer wall of guide rod, 13. Lining of electrolytic cell, 14. Thermal insulation material, 15. Device shell, 16. Heat shield, 17. Graphite anode cover, 18. Graphite Gas collecting pipe, 19, feeding channel sealing gasket, 20, tubular lining, 21, electrolyte, 22, upper cover sealing gasket, 23, side hole, 24, groove, 25, feeding channel, 26, crystallizer or graphite protection layer.

Detailed ways

The carbonaceous material used in the embodiment of the present invention is graphite.

The NaCl, LiCl, MgCl ₂ , BaCl ₂ and CaCl ₂ used in the examples of the present invention are commercial products.

TiO ₂ , Ce ₂ O ₃ , Nd ₂ O ₃ , MgO and Al ₂ O ₃ used in the examples of the present invention are common industrial products.

The carbon powder used in the embodiment of the present invention is calcined petroleum coke powder, a commercially available product, wherein the weight content of C is ≥ 95%.

The pitch, resin and tar used in the examples of the present invention are commercially available products.

In the embodiment of the present invention, the lining of the electrolytic cell is made of corundum, magnesia-aluminum spinel, fused magnesia brick, magnesia or calcium oxide.

In the embodiment of the present invention, the material of the device shell and the upper cover is stainless steel.

The inert gas used in the embodiment of the present invention is argon.

In the embodiment of the present invention, there is a three-way pipe connected to the ventilation port, one branch pipe in the three-way pipe is used to discharge the CO gas generated during the electrolysis process, the second branch pipe is used to fill the electrolytic cell with inert gas, and the third branch pipe is used to discharge the CO gas generated during the electrolysis process. The first branch pipe is connected to the vacuum system.

In the embodiment of the present invention, when the melting point of the metal particles formed by electrolytic reduction is lower than the electrolysis temperature, the metal particles gather into metal droplets and flow into the grooves around the cathode along the top surface of the cathode, and when the electrolysis reaches a certain level of liquid metal Finally, the liquid metal is drawn out into the vacuum ladle through the vacuum suction tube inserted on the upper cover of the device;

In the embodiment of the present invention, when the melting point of the metal electrolytically reduced on the surface of the cathode is greater than the electrolysis temperature to form granular metal particles, which cannot flow down the top surface of the cathode, as the reaction proceeds, the metal powder cathode product accumulates on the top of the cathode. surface and uneven thickness; at this time, the power can be cut off for a period of time and the carbon anode can be lowered to the metal particles on the top surface of the cathode, and then the anode can be rotated horizontally with the center as the axis to push the metal cathode product to the periphery of the cathode, and then use the slave device The vacuum suction tube inserted in the upper cover of the cathode product is sucked into the vacuum ladle.

In the embodiment of the present invention, when the electrolytically reduced metal particles on the surface of the cathode are dendrites or deposits similar to sponges, if no treatment is performed, these crystals or deposits will grow larger and more, And the accumulation is uneven; in this case, it is necessary to adjust the height of the carbon anode regularly to lower the anode working surface, and rotate the carbon anode to flatten the cathode product; in this case, the cathode product will continue to thicken as the electrolysis progresses , the cathode working surface is also continuously raised until the cathode product reaches a certain thickness; at this time, the electrolysis is stopped, and the electrolyte melt in the electrolytic cell is pressed out by the positive pressure filled with argon; The electrolyte in the device evaporates and crystallizes on the crystallizer in the upper part of the device to obtain the cathode product.

Example 1

The structure of the electrolysis device for producing metal or alloy using metal oxide as raw material is shown in Figure 1.

Including device shell 15, heat preservation material 14, electrolytic cell lining 13, cathode 3, conductor 4, cathode steel rod 5, graphite anode 1, graphite anode cover 17 and anode guide rod;

The top of the device shell 15 is provided with an upper cover 6, and the upper cover 6 is provided with a vacuum suction pipe port 10, a ventilation port 8 and a thermocouple tube interface, and the thermocouple tube interface is provided with a thermocouple tube 7;

The top of the cathode 3 is a graphite anode 1, the graphite anode has a graphite anode cover 17, and the anode guide rod is fixed and sealed with the anode cover 17; wherein the graphite anode 1 is provided with a material chamber 2, and the side wall of the graphite anode 1 is provided with a side hole 23, the side hole 23 communicates the material chamber 2 with the outside of the graphite anode 1;

A feed channel 25 is provided in the anode guide rod to communicate with the feed chamber 2;

The working surface of the graphite anode is a conical concave surface with a high middle and a low outer edge, and a graphite gas collecting pipe 18 is arranged at the highest point, and pores are arranged on the side wall of the graphite gas collecting pipe 18 so that the interior of the graphite gas collecting pipe 18 communicates with the material chamber 2; the cathode works The surface is a conical surface with a high middle and a low outer edge; the distance between the cathode working surface and the graphite anode working surface is 4-20 cm;

The device casing 15 is provided with a heat shield 16, the heat shield 16, and the anode guide rod passes through the heat shield 16;

A groove 24 is arranged on the working surface of the graphite anode, and the depth is 5-15mm; the top of the graphite gas collecting pipe 18 is closed, and the bottom opening communicates with the groove 24 on the working surface of the graphite anode;

The anode guide rod is composed of a guide rod outer wall 12 and a tubular inner lining 20. The inside of the tubular inner lining 20 is used as a feeding channel 25, and the top of the feeding channel 25 is provided with a feeding cover 9; the outer wall 12 of the guide rod is made of steel, and the tubular inner lining 20 The material is refractory material or graphite; wherein the outer wall 12 of the guide rod is sealed and fixed with the graphite anode cover 17;

The device has a set of graphite anodes and cathodes;

The material of the cathode is iron;

The lining of the electrolytic cell is made of corundum alumina bricks;

The distance between each point on the cathode working surface and the anode is equal, and the pole distance is 5-15cm;

The outer surface of the upper part of the electrolytic cell shell is provided with a cooling water jacket;

The electrolysis method is:

The metal oxide used is TiO ₂ ; prepare TiO ₂ powder and carbon powder with a particle size of 80-200 mesh, the proportion of carbon powder and TiO ₂ powder is based on complete reaction and carbon powder is prepared at an excess of 10%, and the reaction based on complete reaction formula is

TiO ₂ +2C=M+2CO;

Mix TiO ₂ and carbon powder evenly and press them into pellets under 40MPa pressure;

Place the electrolyte in the material chamber of the electrolytic cell and the anode, lower the working surface of the anode to the working surface of the cathode, and use the inter-electrode arc to start the roasting of the electrolytic cell; the composition of the electrolyte is KCl+NaCl, and the weight content of KCl is respectively 80%;

Vacuum the device to a vacuum degree ≤ 100Pa, and then pass inert gas to normal pressure;

Pass cooling water into the cooling water jacket on the upper part of the device and keep the water circulating to reduce the temperature of the upper space of the electrolytic cell;

After the electrolyte melts and reaches the electrolysis temperature of 700-900°C, the electrolyte is replenished through the feeding tube in the center of the anode guide rod, so that the electrolyte is higher than the upper surface of the anode, and then the anode is raised so that the pole distance is equal to 4-15cm, and then the graphite anode and The cathode is energized for electrolysis. During electrolysis, the liquid level of the molten electrolyte is controlled to be higher than the side hole, and then pellets are added to the phase material chamber through the feeding tube in the anode conduit until it is full; the current density of the graphite anode is 0.5~3.0 A/cm ² , the electrolysis temperature is 750~900℃; metal Ti is generated on the surface of the cathode;

During the electrolysis process, 2 ^Cl- ions in the electrolyte melt lose 2 electrons on the anode working surface to generate Cl ₂ electrochemical reaction:

The Cl ₂ produced by the reaction rises to the top along the groove on the working surface of the graphite anode, enters the graphite gas collector, and then enters the material chamber from the side hole on the gas collector, and the ball composed of Cl ₂ and TiO ₂ and carbon powder in the material chamber The electrolytic reaction of the agglomerate to generate titanium chloride occurs and dissolves into the electrolyte melt;

It can be seen from the above reaction that when one Cl ₂ enters the material chamber, 2 molecules of CO gas and one KTiCl ₃ chloride are generated after chlorination of TiO ₂ , and the CO gas generated by the reaction in the material chamber enters the electrolyte melt through the side hole, Then the electrolyte melt escapes into the upper space of the electrolytic cell, and is discharged from the electrolytic cell through the ventilation port of the upper cover of this space;

When the CO gas generated in the material chamber enters the electrolyte melt outside the graphite anode through the side hole, the airflow generated also drives the electrolyte melt already rich in titanium chloride in the material chamber into the electrolyte melt outside the graphite anode , at the same time, when the Cl ₂ produced on the working surface of the graphite anode enters the material chamber, it also drives the electrolyte melt with a greatly reduced titanium chloride content into the material chamber, thereby forming a circulation flow of the electrolyte. The flow brings the electrolyte melt rich in titanium chloride into the space on the upper surface of the cathode; on the surface of the cathode, the titanium ions in the titanium chloride are electrolytically reduced to metallic titanium;

The titanium metal generated on the surface of the cathode, depending on the electrolysis temperature, the anode current density and the electrolyte composition, is either powdery metal titanium or dendritic metal titanium or sponge-like metal titanium, but they are all related to the electrolyte on the cathode surface The melt is accompanied together. As the electrolysis process progresses, these cathode products will accumulate more and more, and the thickness will be uneven, which may lead to uneven current distribution between the electrodes. For this reason, it is necessary to cut off the electrolysis power supply after a period of time. The anode descends and rotates the anode to flatten the electrolysis product on the surface of the cathode, and part of the cathode product is spread into the grooves around the cathode, and then power on to continue electrolysis; as the cathode product continues to thicken, the entire anode will gradually Move upward; when the cathode product reaches a certain thickness, stop the electrolysis and lower the anode to the cathode product. Then draw out or press out most of the electrolyte in the electrolytic cell, then distill the electrolyte melt remaining in the cathode product and crystallize it on the crystallizer on the upper part of the device; after the electrolytic cell cools down to normal temperature, open the upper part of the electrolytic device Lift the cover, put out the anode, and take out the electrolysis product;

The advantage of this method is that the chlorination of TiO2 and the electrolysis of titanium chloride are carried out and completed in one device, which can greatly reduce the production process of titanium.

Example 2

The structure of the electrolysis device for producing metal or alloy with metal oxide as raw material is the same as that of Example 1, the difference is that:

(1) The device is equipped with three sets of graphite anodes and cathodes;

(2) The material of the cathode is metal molybdenum;

(3) Replace the metal crystallizer with a graphite protective layer;

Electrolysis method is with embodiment 1, and difference is:

(1) The metal oxide used is the oxide of mixed rare earth metal; prepare mixed rare earth metal oxide powder and carbon powder with a particle size of 80~200 mesh, the proportion of carbon powder and mixed rare earth metal oxide powder is based on complete reaction and carbon powder The powder is prepared in excess of 5%, and the reaction formula on which the complete reaction is based is

RE ₂ O ₃ +3C=2RE+3CO;

(2) Mix Re ₂ O ₃ powder and carbon powder evenly, add binder resin; after mixing evenly, press it into a sphere at a temperature of 20°C and a pressure of 100MPa, and then cover the sphere with carbon powder to isolate the air , and then roasted at a temperature of 500~600°C for 10 hours to make pellets;

(3) The composition of the electrolyte is a mixture of KCl and NaCl, of which KCl is 30-70%, and the rest is NaCl;

(4) The current density of the graphite anode is 0.5~6.0A/cm ² , the electrolysis temperature is 800~900℃; mixed rare earth metals are generated on the surface of the cathode

The electrolytic reaction is:

anode

cathode

The mixed rare earth metal electrolytically generated on the cathode is in a liquid state, deposited on the slope of the cathode and then flows into the groove around the cathode. Suction tubes protruding through open holes to suck liquid misch metal from tanks into vacuum ladles

(5) In this embodiment, the production of mixed rare earth metals by using mixed rare earths as raw materials and integrating chlorination and electrolysis is carried out continuously.

Example 3

In this embodiment, a kind of device structure integrating chlorination and electrolysis for producing metal or alloy is the same as that in Embodiment 1, the difference is that:

(1) The device is equipped with five sets of graphite anodes and cathodes;

(2) The material of the cathode is metal molybdenum;

(3) Replace the metal crystallizer with a graphite protective layer;

Electrolysis method is with embodiment 1, and difference is:

(1) The metal oxides used are MgO and Nd ₂ O ₃ ; prepare MgO powder, Nd ₂ O ₃ powder and carbon powder with a particle size of 80-200 mesh, and the ratio of carbon powder to MgO and Nd ₂ O ₃ is based on the complete reaction And the carbon powder is prepared in excess of 8%, and the reaction formula based on the complete reaction is

2MgO+Nd ₂ O ₃ +5C=2MgNd+5CO;

(2) Mix MgO powder, Nd ₂ O ₃ powder and carbon powder evenly, add binder tar; after mixing evenly, press it into a sphere at a temperature of 100°C and a pressure of 50MPa, and then cover the sphere with carbon powder for use It is isolated from the air, and then roasted at a temperature of 500~600°C for 6 hours to make pellets;

(3) The weight content of KCl in the composition of the electrolyte is 50-70%, and the rest is MgCl ₂ of equal mass;

(4) The current density of the graphite anode is 0.5~6.0A/cm ² , and the electrolysis temperature is 800~900℃; MgNd alloy is formed on the surface of the cathode;

During the electrolysis process, when _Cl from the graphite anode working surface enters the feed chamber, it will react with the above-mentioned pellets in the feed chamber and KCl in the electrolyte melt for chlorination and compounding reaction:

2MgO+Nd ₂ O ₃ +5C+5Cl ₂ +8KCl=2K ₃ NdCl ₆ +2KMgCl ₃ +5CO

Or 2MgO+Nd ₂ O ₃ +5C+5Cl ₂ +6KCl=2K ₂ NdCl ₅ +2KMgCl ₃ +5CO

The K ₃ NdCl ₆ , K ₂ NdCl ₅ and KMgCl ₃ produced by the reaction are brought into the electrolyte melt outside the graphite anode along with CO gas escaping from the side hole, and enter the graphite anode and cathode working surfaces by means of the circulation flow of the electrolyte In the space between, here, Nd ³⁺ and Mg ²⁺ in K ₃ NdCl ₆ , K ₂ NdCl ₅ and KMgCl ₃ co-precipitate on the cathode surface to form Mg-Nd alloy:

The melting point of MgNd alloy is 800°C. At an electrolysis temperature higher than 800°C, the MgNd alloy electrolytically generated on the cathode is in a liquid state, deposited on the slope of the cathode and flows into the groove around the cathode. The liquid alloy in the groove After reaching a certain height, use the method of vacuum suction to extend the suction pipe from the hole opened on the tank cover to suck the liquid metal neodymium and magnesium alloy from the tank into the vacuum ladle;

(5) This embodiment is a continuous electrolytic production process of MgNd alloy.

Example 4

The structure of the electrolysis device for producing metal or alloy with metal oxide as raw material is the same as that of Example 1, the difference is that:

(1) The device is equipped with ten sets of graphite anodes and cathodes;

(2) The material of the cathode is TiB ₂ -C composite material;

(3) Replace the metal crystallizer with a graphite protective layer;

Electrolysis method is with embodiment 1, and difference is:

(1) The metal oxide used is Al ₂ O ₃ ; prepare Al ₂ O ₃ powder and carbon powder with a particle size of 80-200 mesh, and the ratio of carbon powder to Al ₂ O ₃ is prepared according to the complete reaction and an excess of 10% of the carbon powder , the reaction formula for the complete reaction is

Al ₂ O ₃ +3C=2Al+3CO;

(2) Mix Al ₂ O ₃ powder and carbon powder, add binder pitch; after mixing evenly, press it into a sphere at a temperature of 200°C and a pressure of 10MPa, and then cover the sphere with carbon powder to isolate the air. Then roast at a temperature of 500~600°C for 2 hours to make pellets;

(3) The weight content of KCl in the composition of the electrolyte is 60-80%, and the remaining components are NaCl and LiCl of equal mass;

(4) The current density of the graphite anode is 0.5~1.5A/cm ² , and the electrolysis temperature is 700~850℃;

During the electrolysis process, when the _Cl2 produced from the graphite anode working surface enters the material chamber, it undergoes a chlorination reaction with _{the Al2O3} in the above-mentioned pellets in the material chamber:

Al ₂ O ₃ +3C+3Cl ₂ +2NaCl=2NaAlCl ₄ +3CO

The KAlCl ₄ or NaAlCl ₄ produced by the reaction is brought into the electrolyte melt outside the graphite anode along with CO gas escaped from the side hole of the material chamber, and enters the space between the graphite anode working surface and the cathode working surface by means of the circulation flow of the electrolyte , here, Al ³⁺ in KAlCl ₄ or NaAlCl ₄ is electrolytically reduced to metal Al on the cathode, and its cathodic reaction is:

At the electrolysis temperature, the Al produced by electrolysis on the cathode is in a liquid state, deposits on the slope of the cathode and flows into the groove around the cathode. The hole on the top extends into the suction pipe to suck the liquid metal aluminum from the tank into the vacuum ladle;

According to the above method, V ₂ O ₃ powder, Cr ₂ O ₃ and other rare metals or B ₂ O ₃ powder, Ga ₂ O ₃ powder and In ₂ O ₃ powder are used as metal oxides for electrolysis to obtain metal V, Cr And other rare metals and B, Ga and In.

Claims (10)

1. A device that integrates chlorination-electrolysis to produce metals and alloys, the device includes a device shell, insulation material, electrolyzer liner, cathode, conductor, cathode steel rod, graphite anode, graphite anode cover and The anode guide rod is characterized in that: the top of the shell is provided with an upper cover, and the upper cover is provided with a vacuum suction pipe port, a ventilation port and a thermocouple tube interface; the graphite anode and the graphite anode cover are fixed together on the cathode, and the anode guide The rod is fixed and sealed with the anode cover; the graphite anode is provided with a material chamber, and the side wall of the graphite anode is provided with a side hole to connect the material chamber with the outside of the graphite anode; the anode guide rod is provided with a feeding channel to communicate with the material chamber; the graphite anode The working surface is a conical concave surface with a high center and a low outer edge. There is a graphite gas collecting pipe at the highest point. There are pores on the side wall of the graphite gas collecting pipe to connect the inside of the graphite gas collecting pipe with the material chamber; the cathode working surface is the middle high outer edge. Low conical face. 2. A device for producing metals and alloys integrating chlorination-electrolysis according to claim 1, characterized in that a perforated heat shield is provided above the electrolytic cell in the housing. 3. a kind of device according to claim 1 that integrates chlorination-electrolysis to produce metal and alloy is characterized in that described graphite anode working face is provided with groove, and depth is 5-15mm; The top of the graphite gas collecting pipe is closed, and the bottom opening communicates with the groove on the working surface of the graphite anode; the anode guide rod is composed of the outer wall of the guide rod and a tubular lining, and the inside of the tubular lining is used as a feeding channel, and the top of the feeding channel is There is a feeding cover; the outer wall of the guide rod is made of steel, and the material of the tubular lining is refractory or graphite; the outer wall of the guide rod is sealed and fixed with the graphite anode cover. 4. A device for producing metals and alloys integrating chlorination-electrolysis according to claim 1, characterized in that the material of the cathode is selected from iron, or tungsten, or molybdenum, or carbonaceous materials, Or composites made of other metal borides and carbides. 5. a kind of collection chlorination-electrolysis according to claim 1 is integrated the device for producing metal and alloy, it is characterized in that the distance of described cathode working surface and graphite anode working surface is 4-20 cm; The cover on the top of the device is provided with an exhaust hole and a vacuum nozzle, which can be filled with an argon nozzle and can be inserted into a thermocouple nozzle and a sealing device that can be inserted into an electrolyte tube; the device shell and the device The upper cover is sealed with a vacuum gasket. The shell is made of stainless steel. The upper part of the shell is provided with a stainless steel crystallizer or graphite protective layer close to the inner wall of the shell. The outer wall of the upper shell is provided with a cooling water jacket. 6. A method for producing metal and alloy integrating chlorination-electrolysis is characterized in that the device according to claim 1 is used to carry out in the following steps: (1) Prepare metal oxide powder and carbon powder with a particle size of 80-200 mesh. The ratio of carbon powder and metal oxide powder is prepared according to complete reaction and 0-10% excess carbon powder. The reaction formula based on complete reaction is M _x O _y +yC=xM+yCO; (1) The M _x O _y is one or two of rare metal oxides such as TiO ₂ and V ₂ O ₃ , rare earth metal oxides such as lanthanum and cerium, and other metal oxides such as aluminum, and x is 1 or 2, y is 1, 2 or 3; when M _x O _y is two metal oxides, the ratio of the two metal oxides is determined according to the target alloy composition; (2) Mix the metal oxide and carbon powder evenly and press them into pellets; (3) Put the pellets into the feeding chamber through the feeding channel; (4) Vacuumize the electrolytic cell to a vacuum degree ≤ 100Pa, and then pass an inert gas into the electrolytic cell to normal pressure; (5) Put the electrolyte in the electrolytic cell, then lower the working surface of the anode to the working surface of the cathode, and use the resistance heating of the inter-electrode arc to start the roasting of the electrolytic cell; (6) After that, after the electrolyte melts and reaches the electrolysis temperature of 700-900°C, the electrolyte is replenished through the feeding channel in the middle of the anode guide rod, so that the height of the electrolyte melt is higher than the upper surface of the anode, and then the anode is lifted to make the pole spacing equal to 4 -15cm, electrify the anode carbon block and the cathode for electrolysis, control the liquid level of the molten electrolyte to be higher than the side hole during electrolysis, and the height of the material in the material chamber is higher than the side hole and air hole; the current density of the anode carbon block is 0.3~ 6.0A/cm ² , the electrolysis temperature is 700~1000℃; when the metal oxide powder is one kind of metal oxide in the preparation of pellets, metal is generated on the surface of the cathode; the metal oxide powder in the preparation of pellets is two When a metal oxide is used, an alloy is formed on the surface of the cathode. 7. A method for producing metals and alloys integrating chlorination-electrolysis according to claim 6, characterized in that the weight content of KCl is 50 to 100% in the composition of the electrolyte, and the rest of the composition It is one or both of NaCl, LiCl, MgCl ₂ , BaCl ₂ and CaCl ₂ . 8. A method for producing metals and alloys that integrates chlorination-electrolysis according to claim 6, is characterized in that when metal oxides and carbon powder are mixed uniformly and pressed into pellets, the metal oxides Adding or not adding a binder to the carbon powder; the binder is selected from resin, tar or asphalt; when no binder is added, the metal oxide and the carbon powder are mixed evenly under the pressure of 10~100MPa Pressed into pellets; when adding a binder, first mix the metal oxide, carbon powder and binder evenly, then press it into a sphere at a temperature of 20~200°C and a pressure of 10~100MPa, and then use carbon powder Cover the spheres to isolate the air, and then bake them at a temperature of 500-600°C for 2-10 hours to make pellets. 9. A method for producing metals and alloys that integrates chlorination-electrolysis according to claim 6, is characterized in that when the electrolysis product of the cathode is liquid metal or liquid alloy or metal powder and is collected to the periphery of the cathode When in the groove, the cathode product can be sucked into the vacuum bag by using the vacuum suction pipe inserted from the upper cover of the device, and the whole process is a continuous production process. 10. a kind of collection chlorination-electrolysis according to claim 6 integrates the method for producing metal and alloy, it is characterized in that when cathode product is solid needle-like or spongy metal product or metal, its electrolysis process is An intermittent electrolysis process, after a period of electrolysis, when the dendrite or spongy product of the cathode product is relatively uneven, the electrolysis is stopped, the anode is lowered to the surface of the cathode, and the anode is rotated to flatten the cathode product ; Then lift the anode to keep the original pole distance and continue electrolysis; after repeating the process for many times, the anode continues to rise, and the electrolysis product accumulates thicker; when it reaches a certain thickness, stop the electrolysis; insert it from the upper cover of the device The suction pipe sucks the electrolyte into the vacuum bag, and then vacuum distills the electrolyte remaining in the cathode product to the crystallizer. After the electrolytic cell in the device cools down to room temperature, open the upper cover to take out the electrolytic product.

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