CN116426771A - A kind of preparation and collection method of metallic magnesium - Google Patents

Abstract

The invention discloses a method for preparing and collecting metal magnesium, comprising: S1, mixing magnesium oxide and calcium oxide to obtain a mixture; ball-milling the mixture evenly in a ball mill tank, and then performing high-temperature sintering to obtain a sintered material; S2. After the sintered material is uniformly ball-milled in a ball milling tank, aluminum powder is added to the ball milling tank under an inert atmosphere, and after the ball milling is uniform, it is granulated and formed to obtain pellets; S3. The pellets are subjected to high-temperature reduction reaction in the reaction chamber to obtain Magnesium vapor, after cooling, adheres to the inside of the collection chamber to obtain solid metal magnesium; S4, cool the reaction chamber to 160°C, then pass in an inert gas, open the collection chamber, and sprinkle an appropriate amount into the collection chamber while opening the collection chamber Sulfur powder, then cooled to room temperature, and the solid product attached to the inside of the collection chamber was taken out. The method of the invention has the advantages of environmental protection and low cost in the production process, and the continuity of the preparation and collection process is good, which can save time and improve production efficiency.

Description

A kind of preparation and collection method of metal magnesium

technical field

The invention relates to the technical field of preparing magnesium metal, in particular to a method for preparing and collecting magnesium metal.

Background technique

Metal magnesium is a light and rare metal, which is widely used in the electronics industry and structural metal industry. Especially in the fields of mobile phone casing manufacturing, notebook computer casing manufacturing, engine manufacturing, magnesium-ion batteries, etc., it has a wide range of applications. In the military field, it is used to manufacture flares, pyrotechnics, aircraft alloys, missile casing materials, and to replace titanium, zirconium, and uranium. The preparation methods of metal magnesium mainly include electrolysis and reduction. Among them, the electrolytic method is a relatively mature method, and electrolytic magnesium metal is the mainstream product source in the world magnesium metal trading market. The process of the electrolysis method is relatively complicated. Specifically, the compound of metal magnesium is reacted with hydrochloric acid to produce magnesium chloride, and then the magnesium chloride is dried and added to the electrolytic tank for molten electrolysis. The liquid metal is produced during the electrolysis process, which needs to be protected by argon. The purity of the produced magnesium metal is not high, and it needs secondary melting to remove impurities to become the final high-purity metal magnesium product. At the same time, during the preparation process, a large amount of chlorine gas is produced, and a small amount of chlorine gas leakage will have a serious impact on the environment.

As the concept of green environmental protection is deeply rooted in the hearts of the people, scientific and technological workers are constantly exploring various green and low-cost metal magnesium preparation processes. Wherein the more representative preparation process has:

Calcium carbide high-temperature reduction method, the preparation of magnesium metal by this method first requires the preparation of calcium carbide, the reduction efficiency is low, and the cost is high. At the same time, the reduced metal magnesium product is not effectively separated from the reduction slag. Made into the final product metal magnesium.

Calcium metal reduction method, which uses calcium metal to reduce magnesium oxide, magnesium chloride and other raw materials at high temperature to produce magnesium metal, but the cost is high and industrial production cannot be carried out.

The silicothermal reduction method uses silica powder to reduce magnesium oxide to prepare metallic magnesium. This method has high costs and the production cost of the reducing agent is high, so it is not a high-quality industrial manufacturing method.

In addition to the process of preparing magnesium metal, the method of collecting magnesium metal is also the key to the production efficiency of magnesium metal. This is because the reduction method needs to be carried out at high temperature to prepare metallic magnesium, and if the obtained metallic magnesium is collected at high temperature, it will be exposed to air and oxidized; if it is collected after cooling in the device, it will take a lot of time . Therefore, it is of great significance in production to develop a method for the preparation and collection of metallic magnesium with low cost, high production efficiency, and an environmentally friendly production process.

Contents of the invention

Based on the technical problems existing in the background technology, the present invention proposes a method for preparing and collecting metallic magnesium.

A kind of preparation and collection method of metal magnesium that the present invention proposes, comprises the following steps:

S1. Mix magnesium oxide and calcium oxide to obtain a mixture; mill the mixture evenly in a ball mill tank, and then perform high-temperature sintering to obtain a sintered material;

S2. After pulverizing the sintered material in a ball milling pot, add aluminum powder into the ball milling pot under an inert atmosphere, and granulate and shape the sintered material after uniform ball milling to obtain pellets;

S3. Prepare a collection device, which includes a reaction chamber and a collection chamber connected to the reaction chamber. A cooling water interlayer is provided outside the collection chamber; the granular material is placed in the reaction chamber, and the inert gas is first introduced to evacuate the air. Then the temperature of the reaction chamber is raised to 830-960°C under an inert atmosphere, and the reduction reaction is carried out under vacuum conditions to obtain magnesium vapor. The magnesium vapor is attached to the inside of the collection chamber under the cooling effect of the cooling water interlayer to obtain solid metal magnesium. ;

S4. After the reduction reaction is finished, cool down the reaction chamber to 160°C, then pass in an inert gas, open the collection chamber, and sprinkle an appropriate amount of sulfur powder into the collection chamber while opening the collection chamber, then cool to room temperature, and take out the adhering Collect the solid product inside the chamber and that's it.

In the present invention, calcium oxide is added to prevent impurities such as magnesium oxide hydrate and magnesium carbonate from dissolving during the sintering process. During the heating process, the molten droplets of magnesium carbonate and magnesium oxide crystals will be absorbed by calcium oxide and dispersed into fine droplets to ensure the smooth progress of magnesium oxide decomposition.

Preferably, the molar ratio of magnesium oxide to calcium oxide is 1:(1-2.5).

Preferably, in S1, the ball-to-material ratio of the ball mill is (1-1.2):1, the speed of the ball mill is 13-15r/min, and the ball milling time is 90-150min.

Preferably, in S1, the ball milling ratio is R3:R5:R10=1:(1-1.2):(3-3.2).

Preferably, in S1, the sintering temperature is 460-650° C., and the sintering time is 180-300 min.

Preferably, in S2, the ball-to-material ratio of sintered material ball milling is (0.8-1.3):1, the ball mill speed is 13-15r/min, and the ball milling time is 80-150min; in S2, after adding aluminum powder, the ball mill speed is 13 -15r/min, ball milling time is 30-45min.

Preferably, in S2, the ball milling ratio is R3:R5:R10=(1-5):(1-3):(2-3).

Preferably, the weight of the aluminum powder is 18-22% of the weight of the sintered material.

Preferably, in S2, the granulation pressure is 0.45-0.62Mpa; the particle size of the granules is 8-30mm.

Preferably, in S3, the heating rate is 5-15°C/min; in S3, the reduction reaction time is 4-4.5h.

Preferably, the preparation and collection device includes a reaction chamber and a collection chamber, one end of the collection chamber communicates with the reaction chamber through a flange, and the other end is sealed with a flange cover plate, and an air inlet is provided on the flange cover plate and an exhaust port; the outer side of the collection cavity is provided with a cooling water interlayer; the cooling water interlayer is provided with a cooling water inlet and a cooling water outlet, which are used to ensure the circulating supply of cooling water in the cooling water interlayer.

Preferably, the particle size of the sulfur powder is 15-60 μm.

In S4, the purpose of sprinkling an appropriate amount of sulfur powder is to react with the surface of solid metal magnesium to form a protective layer, thereby preventing oxidation of magnesium at high temperatures.

In the present invention, the solid product collected in S4 is a solid metal magnesium material with sulfide attached on the surface, which can be directly used for casting or used as a raw material for further purification.

Preferably, in S4, it also includes: collecting the remaining reducing slag in the reaction chamber, reusing the reducing slag in S1, mixing magnesium oxide, calcium oxide and reducing slag to obtain a mixture; the weight of the reducing slag It is 20-30% of the weight sum of magnesium oxide, calcium oxide and reducing slag.

In the present invention, the residual reduction slag can be recycled and put into use, wherein the alumina in the reduction slag will react with calcium oxide and magnesium oxide in the subsequent reduction process to form complex products of calcium aluminum magnesium oxide series, which is beneficial to the catalytic decomposition of magnesium oxide .

The beneficial effects of the present invention are as follows:

In the present invention, the mixture of magnesia and calcium oxide is first sintered to form an intermediate product, and then the intermediate product is mixed with aluminum powder, sintered and reduced at high temperature in the reaction vessel to form magnesium vapor, and then collected in the reactor connected to the reaction vessel. In the container, solid metal magnesium is formed under the action of cooling water. When the temperature is lowered to a suitable temperature, the collection container is opened again, and an appropriate amount of sulfur powder is sprinkled into the collection container to make the surface of the solid metal magnesium react to form a sulfide protective layer. Therefore, the oxidation of the solid metal magnesium by the outside air at high temperature is blocked, so that the obtained product does not oxidize. Through the preparation and collection method of the present invention, the obtained solid metallic magnesium material has relatively high purity, can be directly applied to casting, and can also be purified metallic magnesium with higher purity through secondary purification. The method of the invention has the advantages of environmental protection and low cost in the production process, and the continuity of the preparation and collection process is good, which can save time and improve production efficiency.

Description of drawings

Fig. 1 is the schematic diagram of the preparation and collection device of magnesium metal of the present invention. In Figure 1, 1-reaction chamber, 2-collection chamber, 3-cooling water interlayer, 4-cooling water inlet, 5-cooling water outlet, 6-air inlet, 7-exhaust port, 8-flange, 9-flange cover plate, 10-granular material, 11-solid metal magnesium.

Detailed ways

Below, the technical solution of the present invention will be described in detail through specific examples.

Example 1

A method for preparing and collecting metal magnesium, comprising the following steps:

S1. Mix 100kg of magnesium oxide and 140kg of calcium oxide to obtain a mixture; mill the mixture evenly in a ball mill tank, wherein the ball mill speed is 13r/min, the ball milling time is 150min, the ball-to-material ratio is 1:1, and the ball ratio R3:R5:R10=1:1:3 (the material is alumina ceramic balls), and then sintered at 650°C for 180min to obtain the sintered material;

S2. Take 100kg of sintered material and mill it evenly in a ball mill tank. The ball-to-material ratio of the ball mill is 1:1, and the ball distribution ratio is R3:R5:R10=1:1:3 (the material is alumina ceramic balls), and the speed of the ball mill is The ball milling time is 13r/min, the ball milling time is 150min, then argon gas is passed into the ball milling tank for 20min, 20kg aluminum powder is added, and the ball milling is uniform, wherein the ball mill speed is 15r/min, the ball milling time is 45min, and granulated under the pressure of 0.45Mpa Forming to obtain pellets;

S3, prepare to prepare collection device, referring to Fig. 1, this device comprises reaction chamber 1 and collection chamber 2, and one end of described collection chamber 2 communicates with reaction chamber 1 through flange plate 8, and the other end is sealed with flange cover plate 9, method An air inlet 6 and an exhaust port 7 are arranged on the blue cover plate, and a cooling water interlayer 3 is arranged on the outside of the collection chamber 2, and a cooling water inlet 4 and a cooling water outlet 5 are arranged on the cooling water interlayer; In the reaction chamber 1, first pass argon gas through the air inlet 6 for 20 minutes to evacuate the air, then stop the argon gas flow, and raise the temperature of the reaction chamber 1 to 960 °C at a heating rate of 10 °C/min, and then pass through the exhaust port 7. Start vacuuming, keep warm at 960°C for 4.5 hours for reduction reaction, and continue vacuuming during the reduction reaction to obtain magnesium vapor. The magnesium vapor adheres to the inside of the collection chamber 2 under the cooling effect of the cooling water interlayer 3, and solid metal magnesium 11 is obtained. In the reaction process, the cooling water is passed into the cooling water interlayer 3 through the cooling water inlet 4, and the cooling water is discharged through the cooling water outlet 5, thereby ensuring the circulation supply of the cooling water in the cooling water interlayer 3;

S4. After the reduction reaction is finished, cool down the reaction chamber 1 to 160°C, then pass argon gas through the air inlet 6 for 25 minutes, disassemble the flange 8, thereby opening the collection chamber 2, and open the collection chamber 2 while opening the collection chamber 2. Sprinkle 150g of sulfur powder into the collection chamber 2, the particle size of the sulfur powder is 15-60 μm, then cool to room temperature, take out the solid product attached to the inside of the collection chamber 2, and that's it.

Example 2

A method for preparing and collecting metal magnesium, comprising the following steps:

S1. Mix 100kg magnesium oxide and 140kg calcium oxide to obtain a mixture; mill the mixture evenly in a ball mill tank, wherein the ball mill speed is 15r/min, the ball milling time is 90min, the ball-to-material ratio is 1.2:1, and the ball ratio R3:R5:R10=1:1:3 (the material is alumina ceramic balls), and then sintered at 460°C for 300min to obtain the sintered material;

S2. Take 100kg of sintered material and mill it evenly in a ball mill tank. The ball-to-material ratio of the ball mill is 0.8:1, and the ball ratio is R3:R5:R10=1:1:3 (the material is alumina ceramic balls), and the speed of the ball mill is The ball milling time is 15r/min, the ball milling time is 80min, then argon gas is passed into the ball milling tank for 20min, 18kg aluminum powder is added, and the ball milling is uniform, wherein the ball mill speed is 13r/min, the ball milling time is 30min, and granulated under the pressure of 0.62Mpa Forming to obtain pellets;

S3, prepare to prepare collection device, referring to Fig. 1, this device comprises reaction chamber 1 and collection chamber 2, and one end of described collection chamber 2 communicates with reaction chamber 1 through flange plate 8, and the other end is sealed with flange cover plate 9, method An air inlet 6 and an exhaust port 7 are arranged on the blue cover plate, and a cooling water interlayer 3 is arranged on the outside of the collection chamber 2, and a cooling water inlet 4 and a cooling water outlet 5 are arranged on the cooling water interlayer; In the reaction chamber 1, first pass argon gas through the air inlet 6 for 20 minutes to evacuate the air, then stop the argon flow, and raise the temperature of the reaction chamber 1 to 830°C at a temperature increase rate of 5°C/min, and then pass through the exhaust port 7. Start vacuuming, heat-preserve the reduction reaction at 830° C. for 4 hours, and continue vacuuming during the reduction reaction to obtain magnesium vapor. The magnesium vapor adheres to the inside of the collection chamber 2 under the cooling effect of the cooling water interlayer 3 to obtain solid metal magnesium 11; In the reaction process, the cooling water is passed into the cooling water interlayer 3 through the cooling water inlet 4, and the cooling water is discharged through the cooling water outlet 5, thereby ensuring the circulating supply of cooling water in the cooling water interlayer 3;

S4. After the reduction reaction is finished, cool down the reaction chamber 1 to 160°C, then pass argon gas through the air inlet 6 for 25 minutes, disassemble the flange 8, thereby opening the collection chamber 2, and open the collection chamber 2 while opening the collection chamber 2. Sprinkle 100g of sulfur powder into the collection chamber 2, the particle size of the sulfur powder is 15-60 μm, then cool to room temperature, take out the solid product attached to the inside of the collection chamber 2, and that's it.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any person familiar with the technical field within the technical scope disclosed in the present invention, according to the technical solution of the present invention Any equivalent replacement or change of the inventive concepts thereof shall fall within the protection scope of the present invention.

Claims (10)

1. a preparation and collection method of metal magnesium, is characterized in that, comprises the following steps: S1. Mix magnesium oxide and calcium oxide to obtain a mixture; mill the mixture evenly in a ball mill tank, and then perform high-temperature sintering to obtain a sintered material; S2. After pulverizing the sintered material in a ball milling pot, add aluminum powder into the ball milling pot under an inert atmosphere, and granulate and shape the sintered material after uniform ball milling to obtain pellets; S3. Prepare a collection device, which includes a reaction chamber and a collection chamber connected to the reaction chamber. A cooling water interlayer is provided outside the collection chamber; the granular material is placed in the reaction chamber, and the inert gas is first introduced to evacuate the air. Then the temperature of the reaction chamber is raised to 830-960°C under an inert atmosphere, and the reduction reaction is carried out under vacuum conditions to obtain magnesium vapor. The magnesium vapor is attached to the inside of the collection chamber under the cooling effect of the cooling water interlayer to obtain solid metal magnesium. ; S4. After the reduction reaction is finished, cool down the reaction chamber to 160°C, then pass in an inert gas, open the collection chamber, and sprinkle an appropriate amount of sulfur powder into the collection chamber while opening the collection chamber, then cool to room temperature, and take out the adhering Collect the solid product inside the chamber and that's it. 2. The preparation and collection method of metallic magnesium according to claim 1, characterized in that the molar ratio of magnesium oxide to calcium oxide is 1: (1-2.5). 3. the preparation and collection method of metallic magnesium according to claim 1 is characterized in that, in S1, the ball-to-material ratio of ball mill is (1-1.2): 1, and ball mill rotating speed is 13-15r/min, and ball milling time 90 -150min. 4. The method for preparing and collecting metallic magnesium according to claim 1, characterized in that, in S1, the sintering temperature is 460-650°C, and the sintering time is 180-300min. 5. the preparation and collection method of metal magnesium according to claim 1 is characterized in that, in S2, the ball-to-material ratio of sinter ball mill is (0.8-1.3): 1, and the ball mill rotating speed is 13-15r/min, ball mill The time is 80-150min; in S2, after adding aluminum powder, the speed of the ball mill is 13-15r/min, and the ball milling time is 30-45min. 6. The method for preparing and collecting metallic magnesium according to claim 1, characterized in that the weight of the aluminum powder is 18-22% of the weight of the sintered material. 7. The method for preparing and collecting metal magnesium according to claim 1, characterized in that, in S2, the pressure of granulation and molding is 0.45-0.62Mpa; the particle size of the granules is 8-30mm. 8. The method for preparing and collecting metal magnesium according to claim 1, characterized in that, in S3, the heating rate is 5-15° C./min; in S3, the reduction reaction time is 4-4.5 h. 9. The method for preparing and collecting metal magnesium according to claim 1, characterized in that the particle size of the sulfur powder is 15-60 μm. 10. The method for preparing and collecting magnesium metal according to claim 1, characterized in that, in S4, it also includes: collecting the remaining reducing slag in the reaction chamber, reusing the reducing slag in S1, and reusing the magnesium oxide . Calcium oxide is mixed with reducing slag to obtain a mixture; the weight of the reducing slag is 20-30% of the sum of the weight of magnesium oxide, calcium oxide and reducing slag.

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