Graphite-carbon aerogel composite material capable of preventing molten salt permeation as well as preparation method and application of graphite-carbon aerogel composite material

Abstract

The invention relates to a graphite-carbon aerogel composite material for preventing molten salt permeation and a preparation method and application thereof. The preparation method comprises the following steps: S1, sol preparation: dissolving asphalt, furfural and concentrated sulfuric acid in a solvent, and reacting to obtain sol; s2, gel reaction: immersing graphite in the sol, and heating for gel reaction to obtain a graphite / asphalt-based organic gel complex; s3, drying: drying the graphite / asphalt-based organic gel complex at normal pressure to obtain a graphite-aerogel composite material; and S4, carbonizing: carbonizing and cracking the graphite-aerogel composite material under the protection of inert gas to obtain the fused salt permeation-resistant graphite-carbon aerogel composite material. Compared with the prior art, the graphite-carbon aerogel composite material prepared by the invention has the advantages of excellent molten salt penetration resistance, high-temperature molten salt corrosion resistance, easily available raw materials, low cost and simple preparation process.

Description

Technical Field

[0001] The present invention relates to the field of preparation of carbon aerogel composites, and in particular to a graphite-carbon aerogel composite with anti-molten salt penetration, a preparation method thereof, and an application thereof. Background Art

[0002] As one of the six candidate reactor types of the fourth-generation nuclear reactor, the molten salt reactor has received wide attention due to its advantages such as high safety, operation at normal pressure, and high efficiency. In the molten salt reactor, nuclear graphite is usually used as a reflector, a moderator, and a core structure material, while ensuring the integrity of the entire core structure, forming a flow channel for the molten salt coolant. However, due to the porous characteristics of graphite materials, molten salt (fuel salt) is easily penetrated into the pores of graphite, resulting in a decrease in its anti-irradiation performance, a change in the thermal expansion coefficient, accelerating the damage of graphite, and thus shortening its service life. Therefore, in addition to nuclear purity and radiation resistance characteristics, graphite materials for molten salt reactors must also have good anti-molten salt penetration performance.

[0003] At present, nuclear graphite, as a neutron moderator and a structural material, is mainly used in gas-cooled reactors. In contrast, the research and development of nuclear graphite for molten salt reactors is relatively slow, and a mature anti-molten salt penetration technology has not yet been formed. CN109081695A discloses a preparation method of a high-density large-size ultra-fine pore nuclear graphite material for molten salt reactors, including the following steps: kneading, vibrating and compacting, roasting, impregnating with an impregnating agent, and graphitizing / nuclear purity treatment of coke aggregates and binders to prepare a nuclear graphite material with a length of 1000-1500 mm, a width of 500-1000 mm, and a height of 300-500 mm. This preparation process is relatively complex.

[0004] The density of commercial nuclear graphite is generally between 1.7-1.9 g / cm 3 For example, an IG-110 nuclear graphite with a density of about 1.75 g / cm 3 is the current international mainstream nuclear graphite material for high-temperature gas-cooled reactors, but this graphite will undergo molten salt infiltration under the operating environment of a molten salt reactor (5 atmospheres) and cannot be used in molten salt reactors.

[0005] Therefore, how to develop a nuclear graphite material with excellent anti-molten salt penetration performance through a relatively simple process based on commercial nuclear graphite is one of the key technologies to promote the commercialization of molten salt reactors. Summary of the Invention

[0006] The purpose of the present invention is to overcome the problem that traditional nuclear graphite materials are easily penetrated by fuel salts in the molten salt reactor environment, and thus provide a graphite-carbon aerogel composite with anti-molten salt penetration, a preparation method thereof, and an application thereof.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] One of the technical solutions of the present invention is to provide a preparation method of a graphite-carbon aerogel composite material for preventing molten salt penetration, including the following steps:

[0009] S1. Sol preparation: Dissolve asphalt, furfural, and concentrated sulfuric acid in a solvent, and react to obtain a sol;

[0010] S2. Gel reaction: Immerse graphite in the sol obtained in step S1, and heat for gel reaction to obtain a graphite / asphalt-based organic gel composite;

[0011] S3. Drying: Dry the graphite / asphalt-based organic gel composite obtained in step S2 under normal pressure to obtain a graphite-aerogel composite material;

[0012] S4. Carbonization: Carbonize and crack the graphite-aerogel composite material obtained in step S3 under the protection of an inert gas to obtain a graphite-carbon aerogel composite material for preventing molten salt penetration.

[0013] In this technical solution, carbon aerogel is a lightweight and porous carbon material composed of carbon nanoparticles, which can resist high-temperature molten salt corrosion in an inert atmosphere. However, traditional carbon aerogels prepared from resorcinol and formaldehyde have problems such as high cost and complex processes. In this technical solution, graphite is compounded with carbon aerogel, and carbon aerogel nanoparticles are filled inside the pores of graphite. On the one hand, it improves the density of the material; on the other hand, it reduces the pore permeability; on the third hand, the pore diameter of graphite becomes smaller, and the greater the external air pressure required for molten salt to penetrate into the pores of graphite. According to the Washburn theoretical formula, the better the molten salt penetration resistance performance. The present invention develops a method with low cost and simple process to prepare a graphite-carbon aerogel composite material for preventing molten salt penetration, as a nuclear graphite material for molten salt reactors, to further expand the application range of carbon aerogel composite materials.

[0014] In some specific embodiments, in step S1, the asphalt is selected from any one or more of coal tar pitch, petroleum asphalt, bio-asphalt, and synthetic asphalt.

[0015] The solvent is a mixture of toluene and acetic acid.

[0016] More preferably, the solvent is a mixture of toluene and acetic acid mixed in a volume ratio of 1:1.

[0017] In some specific embodiments, in step S1, the ratio of the asphalt to furfural is (1 / 3 - 2 / 3) g:1 mL, the ratio of the asphalt to concentrated sulfuric acid is (2.5 - 10) g:1 mL, and the ratio of the asphalt to the solvent is (0.1 - 0.2) g:1 mL.

[0018] In this technical solution, different concentrations of acid have a certain impact on the preparation effect of carbon aerogel. If the proportion of acid / asphalt raw material is too low, it will lead to insufficient catalytic effect and an unstable structure of the formed carbon aerogel; if the proportion of acid / asphalt raw material is too high, it will lead to too fast reaction or excessive carbonization, and the aerogel characteristics will be lost.

[0019] In some specific embodiments, in step S2, the graphite is selected from any one or more of IG-110, IG-430, NBG-17, NBG-18, H451, T220, and NG-CT-50. All of the graphite are nuclear graphite materials for nuclear fission reactors.

[0020] In some specific embodiments, in step S2, the temperature of the gel reaction is 60-95°C and the time is (160-170) h.

[0021] In this technical solution, if the temperature is lower than 60°C of the gel temperature, the gel reaction cannot occur; if the temperature is higher than 95°C of the gel temperature, the gel reaction also cannot occur.

[0022] More preferably, in step S2, the temperature of the gel reaction is 60-95°C and the time is 168 h.

[0023] In some specific embodiments, in step S3, the process of atmospheric drying is as follows: first dry at room temperature for (20-25) h, then dry by infrared drying at (45-55)°C for (3-7) h, and finally dry in an oven at (95-105)°C for (3-7) h.

[0024] More preferably, in step S3, the process of atmospheric drying is as follows: first dry at room temperature for 24 h, then dry by infrared drying at 50°C for 5 h, and finally dry in an oven at 100°C for 5 h.

[0025] The purpose of atmospheric drying is to remove the solvent remaining in the graphite / asphalt-based organic gel composite. If this step is omitted, on the one hand, it will damage the subsequent heat treatment equipment, and on the other hand, it will lead to the failure of the preparation of carbon aerogel.

[0026] In some specific embodiments, in step S4, the inert atmosphere is selected from any one of nitrogen and argon.

[0027] In some specific embodiments, in step S4, the carbonization process is as follows: heat up to 700-1100°C at a heating rate of 2-8°C / min, keep the temperature for 1-12 h, and then cool to room temperature with the furnace.

[0028] The second technical solution of the present invention is to provide a graphite-carbon aerogel composite material for preventing molten salt penetration, which is obtained based on the preparation method described in the above technical solution one.

[0029] The third technical solution of the present invention provides an application of the graphite-carbon aerogel composite material for preventing molten salt penetration as described in the second technical solution above, and the graphite-carbon aerogel composite material for preventing molten salt penetration is used as a nuclear graphite material for molten salt reactors.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) Low cost and process optimization

[0032] The raw material used to prepare the carbon aerogel in the present invention is pitch, which is low in cost and suitable for large-scale preparation. Furfural is used as a cross-linking agent to react with polycyclic aromatic hydrocarbons in pitch under acid catalysis conditions to form a three-dimensional network structure of organic aerogel. Concentrated sulfuric acid is used as a catalyst to promote the formation of the gel and improve the reaction rate. The atmospheric drying process has the advantages of simple process, low cost, and short synthesis cycle (without multiple steps such as solvent replacement and pressure and temperature increase) compared with the traditional supercritical drying method.

[0033] (2) Excellent molten salt penetration prevention performance

[0034] In the present invention, through the sol-gel process, the gel can fully fill the pores of the graphite material, improving the density of the material; after high-temperature carbonization treatment, a stable carbon aerogel network structure is formed, enhancing the anti-penetration ability.

[0035] (3) Compatibility with existing nuclear graphite materials

[0036] The present invention combines existing commercial nuclear graphite with carbon aerogel, which has excellent molten salt resistance, high-temperature molten salt corrosion resistance and other characteristics, and can be used as nuclear graphite for molten salt reactors. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a process flow chart of the method of the present invention.

[0038] Figure 2 It is an SEM image of the graphite-carbon aerogel composite material prepared in Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0039] The present invention will be described in detail below with reference to the drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and the detailed implementation manner and specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0040] In the following embodiments, unless otherwise specified, the raw materials or treatment techniques are all conventional commercially available raw material products or conventional treatment techniques in the art.

[0041] Example 1

[0042] This embodiment provides a method for preparing a graphite-carbon aerogel composite material resistant to molten salt penetration, as follows: Figure 1 shown, the specific steps are as follows:

[0043] (1) Raw material ratio and sol preparation: Take 5 g of petroleum asphalt, 10 mL of furfural, and 1 mL of concentrated sulfuric acid with a mass fraction of 98%, dissolve them in a mixed solvent of 25 mL of toluene and 25 mL of acetic acid, and after ultrasonic dispersion and stirring evenly, react to obtain a sol;

[0044] (2) Gel reaction: Place the IG-110 graphite sample in the sol obtained in step (1), and heat it at 70 °C for 168 hours for gel reaction to obtain a graphite / petroleum asphalt-based organic gel composite;

[0045] (3) Drying: The graphite / petroleum asphalt-based organic gel composite obtained in step (2) is successively dried at room temperature for 24 h, infrared dried at 50 °C for 5 h, and oven dried at 100 °C for 5 h under normal pressure to obtain a graphite-aerogel composite material;

[0046] (4) Carbonization: Under a nitrogen atmosphere, heat the graphite-aerogel composite material obtained in step (3) to 900 °C at a rate of 5 °C / min, hold for 5 hours, and then cool to room temperature with the furnace to obtain a graphite-carbon aerogel composite material.

[0047] As Figure 2 shown by SEM observation, the carbon aerogel particles have uniform sizes, with a diameter of about 40 - 50 nm, and are filled in the open pores of the graphite material. The density of the graphite-carbon aerogel composite material is 1.833 g / cm 3 . The graphite-carbon aerogel composite material does not undergo surface corrosion in a high-temperature inert molten salt environment and has high-temperature molten salt corrosion resistance.

[0048] Example 2

[0049] This embodiment provides a method for preparing a graphite-carbon aerogel composite material resistant to molten salt penetration, and the specific steps are as follows:

[0050] (1) Raw material ratio and sol preparation: Take 5 g of petroleum asphalt, 15 mL of furfural, and 1 mL of concentrated sulfuric acid with a mass fraction of 98%, dissolve them in a mixed solvent of 25 mL of toluene and 25 mL of acetic acid, and after ultrasonic dispersion and stirring evenly, react to obtain a sol;

[0051] (2) Gel reaction: Place the IG-110 graphite sample in the sol obtained in step (1), and heat it at 70 °C for 168 hours for gel reaction to obtain a graphite / petroleum asphalt-based organic gel composite;

[0052] (3) Drying treatment: The graphite / petroleum pitch-based organic gel composite obtained in step (2) is successively dried at room temperature for 24 h, dried by infrared at 50 °C for 5 h, and dried in an oven at 100 °C for 5 h under normal pressure to obtain a graphite aerogel composite material;

[0053] (4) Carbonization: Under a nitrogen atmosphere, the graphite aerogel composite material obtained in step (3) is heated to 900 °C at a rate of 5 °C / min, held for 5 h, and then cooled to room temperature with the furnace to obtain a graphite-carbon aerogel composite material.

[0054] In this example, the ratio of petroleum pitch to furfural was reduced based on Example 1. After testing, the density of the prepared graphite-carbon aerogel composite material increased to a certain extent, as shown in Table 1.

[0055] Example 3

[0056] This example provides a method for preparing a molten salt-permeation-proof graphite-carbon aerogel composite material, and the specific steps are as follows:

[0057] (1) Raw material ratio and sol preparation: Take 5 g of petroleum pitch, 10 mL of furfural, and 2 mL of concentrated sulfuric acid with a mass fraction of 98%, dissolve them in a mixed solvent of 25 mL of toluene and 25 mL of acetic acid, and after ultrasonic dispersion and stirring evenly, react to obtain a sol;

[0058] (2) Gel reaction: Place the IG-110 graphite sample in the sol obtained in step (1), and heat it at 70 °C for 168 hours for gel reaction to obtain a graphite / petroleum pitch-based organic gel composite;

[0059] (3) Drying treatment: The graphite / petroleum pitch-based organic gel composite obtained in step (2) is successively dried at room temperature for 24 h, dried by infrared at 50 °C for 5 h, and dried in an oven at 100 °C for 5 h under normal pressure to obtain a graphite aerogel composite material;

[0060] (4) Carbonization: Under a nitrogen atmosphere, the graphite aerogel composite material obtained in step (3) is heated to 900 °C at a rate of 5 °C / min, held for 5 h, and then cooled to room temperature with the furnace to obtain a graphite-carbon aerogel composite material.

[0061] In this example, the ratio of concentrated sulfuric acid was increased based on Example 1. After testing, the density of the prepared graphite-carbon aerogel composite material changed little, as shown in Table 1.

[0062] Example 4

[0063] This example provides a method for preparing a molten salt-permeation-proof graphite-carbon aerogel composite material, and the specific steps are as follows:

[0064] (1) Raw material ratio and sol preparation: Take 5 g of petroleum asphalt, 10 mL of furfural, and 0.5 mL of concentrated sulfuric acid with a mass fraction of 98%, dissolve them in a mixed solvent of 25 mL of toluene and 25 mL of acetic acid. After ultrasonic dispersion and stirring evenly, react to obtain a sol;

[0065] (2) Gel reaction: Place the IG-110 graphite sample in the sol obtained in step (1), and heat it at 70 °C for 168 hours for gel reaction to obtain a graphite / petroleum asphalt-based organic gel composite;

[0066] (3) Drying treatment: Subject the graphite / petroleum asphalt-based organic gel composite obtained in step (2) to normal pressure drying by drying at room temperature for 24 h, infrared drying at 50 °C for 5 h, and oven drying at 100 °C for 5 h in sequence to obtain a graphite aerogel composite material;

[0067] (4) Carbonization: Under a nitrogen atmosphere, heat the graphite aerogel composite material obtained in step (3) to 900 °C at a rate of 5 °C / min, hold for 5 h, and then cool to room temperature with the furnace to obtain a graphite-carbon aerogel composite material.

[0068] In this example, the ratio of concentrated sulfuric acid was reduced based on Example 1. After testing, the density of the prepared graphite-carbon aerogel composite material decreased to a certain extent, as shown in Table 1.

[0069] Example 5

[0070] This example provides a method for preparing a molten salt-permeation-proof graphite-carbon aerogel composite material, and the specific steps are as follows:

[0071] (1) Raw material ratio and sol preparation: Take 5 g of petroleum asphalt, 10 mL of furfural, and 1 mL of concentrated sulfuric acid with a mass fraction of 98%, dissolve them in a mixed solvent of 12.5 mL of toluene and 12.5 mL of acetic acid. After ultrasonic dispersion and stirring evenly, react to obtain a sol;

[0072] (2) Gel reaction: Place the IG-110 graphite sample in the sol obtained in step (1), and heat it at 70 °C for 168 hours for gel reaction to obtain a graphite / petroleum asphalt-based organic gel composite;

[0073] (3) Drying treatment: Subject the graphite / petroleum asphalt-based organic gel composite obtained in step (2) to normal pressure drying by drying at room temperature for 24 h, infrared drying at 50 °C for 5 h, and oven drying at 100 °C for 5 h in sequence to obtain a graphite aerogel composite material;

[0074] (4) Carbonization: Under a nitrogen atmosphere, the graphite-aerogel composite material obtained in step (3) is heated to 900 °C at a rate of 5 °C / min, held for 5 h, and then cooled to room temperature in the furnace to obtain a graphite-carbon aerogel composite material.

[0075] In this example, based on Example 1, by reducing the content of the toluene and acetic acid mixed solvent, a higher density graphite-carbon aerogel composite material is obtained, further improving the pore structure of the graphite material, as shown in Table 1.

[0076] Example 6

[0077] This example provides a method for preparing a molten salt permeation-proof graphite-carbon aerogel composite material, and the specific steps are as follows:

[0078] (1) Raw material ratio and sol preparation: Take 5 g of petroleum pitch, 10 mL of furfural, and 1 mL of concentrated sulfuric acid with a mass fraction of 98%, dissolve them in a mixed solvent of 25 mL of toluene and 25 mL of acetic acid, and after ultrasonic dispersion and stirring evenly, react to obtain a sol;

[0079] (2) Gel reaction: Place the IG-110 graphite sample in the sol obtained in step (1), and carry out a gel reaction by heating at 70 °C for 168 hours to obtain a graphite / petroleum pitch-based organic gel complex;

[0080] (3) Drying treatment: The graphite / petroleum pitch-based organic gel complex obtained in step (2) is successively dried at room temperature for 24 h, infrared dried at 50 °C for 5 h, and oven dried at 100 °C for 5 h under normal pressure to obtain a graphite-aerogel composite material;

[0081] (4) Carbonization: Under a nitrogen atmosphere, the graphite-aerogel composite material obtained in step (3) is heated to 1000 °C at a rate of 5 °C / min, held for 5 h, and then cooled to room temperature in the furnace to obtain a graphite-carbon aerogel composite material.

[0082] In this example, based on Example 1, by increasing the carbonization temperature, after testing, the density of the prepared graphite-carbon aerogel composite material is reduced to a certain extent, as shown in Table 1.

[0083] Example 7

[0084] This example provides a method for preparing a molten salt permeation-proof graphite-carbon aerogel composite material, and the specific steps are as follows:

[0085] (1) Raw material ratio and sol preparation: Take 5 g of petroleum pitch, 10 mL of furfural, and 1 mL of concentrated sulfuric acid with a mass fraction of 98%, dissolve them in a mixed solvent of 25 mL of toluene and 25 mL of acetic acid, and after ultrasonic dispersion and stirring evenly, react to obtain a sol;

[0086] (2) Gel reaction: Place the IG-110 graphite sample in the sol obtained in step (1), and carry out a gel reaction by heating at 70 °C for 168 hours to obtain a graphite / petroleum pitch-based organic gel composite;

[0087] (3) Drying: The graphite / petroleum pitch-based organic gel composite obtained in step (2) is successively dried at room temperature for 24 h, dried by infrared at 50 °C for 5 h, and dried in an oven at 100 °C for 5 h under normal pressure drying to obtain a graphite aerogel composite material;

[0088] (4) Carbonization: Under a nitrogen atmosphere, heat the graphite aerogel composite material obtained in step (3) to 900 °C at a rate of 8 °C / min, hold for 5 hours, and then cool to room temperature with the furnace to obtain a graphite-carbon aerogel composite material.

[0089] Based on Example 1, this example prepares a graphite-carbon aerogel composite material by increasing the carbonization heating rate. After testing, the density of the prepared graphite-carbon aerogel composite material changes little, as shown in Table 1.

[0090] The graphite used in Examples 1 to 7 is Toyo IG-110 nuclear graphite from Japan, and the density of this graphite is about 1.75 g / cm 3 , which is the current international mainstream nuclear graphite material for high-temperature gas-cooled reactors. However, this graphite will undergo molten salt infiltration in the operating environment of a molten salt reactor (5 atmospheres), so it cannot be used in molten salt reactors.

[0091] Table 1 Reaction conditions of Examples 1-7 and density values of the prepared graphite-carbon aerogel composite materials

[0092]

[0093] Perform a high-temperature molten salt immersion test on the graphite-carbon aerogel composite material samples prepared in Examples 1-7 of this example. Test conditions: 2LiF-BeF2 molten salt, temperature: 700 °C, time: 20 h, pressure: 5 atm, and the sample is vacuum-treated before being immersed in the molten salt.

[0094] The most accessible pore diameter of the IG-110 graphite used in the examples is about 2 μm. After testing, the molten salt infiltration volume of the graphite-carbon aerogel composite material samples is less than 0.5% of the total pore volume of the graphite.

[0095] After research, when the most accessible pore diameter of the graphite is <1 μm, no molten salt infiltration occurs in the molten salt reactor environment (the maximum molten salt covering pressure is 5 atmospheres) (doi: 10.1007 / s10853-017-1310-4.). It can be seen that in the molten salt reactor environment, the graphite-carbon aerogel composite materials prepared in Examples 1-7 of this example all meet the performance requirements of preventing molten salt infiltration and preventing molten salt corrosion.

[0096] The above description of the embodiments is provided to enable those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and all improvements and modifications made by those skilled in the art without departing from the scope of the present invention according to the disclosure of the present invention should be within the protection scope of the present invention.

Claims

1. A preparation method of a graphite-carbon aerogel composite material resistant to molten salt penetration, characterized in that, It includes the following steps: S1. Sol Preparation: Dissolve asphalt, furfural, and concentrated sulfuric acid in a solvent and react to obtain a sol; S2. Gel Reaction: Immerse a graphite sample in the sol obtained in step S1, heat to carry out a gel reaction to obtain a graphite / asphalt-based organic gel composite; S3. Drying: Atmospherically dry the graphite / asphalt-based organic gel composite obtained in step S2 to obtain a graphite-aerogel composite material; S4. Carbonization: Under the protection of an inert gas, carbonize and crack the graphite-aerogel composite material obtained in step S3 to obtain a graphite-carbon aerogel composite material resistant to molten salt penetration.

2. The preparation method of the graphite-carbon aerogel composite material for preventing molten salt penetration according to claim 1, characterized in that, In step S1, the asphalt is selected from any one or more of coal tar pitch, petroleum asphalt, bio-asphalt, and synthetic asphalt.

3. The preparation method of the graphite-carbon aerogel composite material for preventing molten salt penetration according to claim 1, characterized in that, In step S1, the ratio of the asphalt to furfural is (1 / 3 - 2 / 3) g:1 mL, the ratio of the asphalt to concentrated sulfuric acid is (2.5 - 10) g:1 mL, and the ratio of the asphalt to the solvent is (0.1 - 0.2) g:1 mL.

4. The preparation method of the graphite-carbon aerogel composite material for preventing molten salt penetration according to claim 1, wherein In step S2, the graphite is selected from any one or more of IG-110, IG-430, NBG-17, NBG-18, H451, T220, and NG-CT-50.

5. The preparation method of the graphite-carbon aerogel composite material for preventing molten salt penetration according to claim 1, characterized in that, In step S2, the temperature of the gel reaction is 60 - 95 °C, and the time is (160 - 170) h.

6. The preparation method of the graphite-carbon aerogel composite material for preventing molten salt penetration according to claim 1, characterized in that, In step S3, the atmospheric drying process is: first dry at room temperature for (20 - 25) h, then dry by infrared drying at (45 - 55) °C for (3 - 7) h, and finally dry in an oven at (95 - 105) °C for (3 - 7) h.

7. The preparation method of the graphite-carbon aerogel composite material for preventing molten salt penetration according to claim 1, characterized in that, In step S4, the inert atmosphere is selected from any one of nitrogen and argon.

8. The preparation method of the graphite-carbon aerogel composite material for preventing molten salt penetration according to claim 1, wherein, In step S4, the carbonization process is: heat at a heating rate of 2 - 8 °C / min to 700 - 1100 °C, hold for 1 - 12 h, and then cool to room temperature with the furnace.

9. A graphite-carbon aerogel composite material for preventing molten salt penetration, characterized in that, Obtained based on any one of claims 1 - 8.

10. Use of a graphite-carbon aerogel composite material for preventing molten salt penetration as described in claim 9, characterized in that, The graphite-carbon aerogel composite material resistant to molten salt penetration is used as a nuclear graphite material for a molten salt reactor.

Images