Preparation method and application of a nickel-based aerogel catalyst

Abstract

The application belongs to the technical field of energy materials, and particularly relates to a nickel-based aerogel catalyst and a preparation method and application thereof; the preparation method specifically comprises the following steps: S1, uniformly mixing anhydrous ethanol, tetramethoxysilane and dimethylacetamide, and then uniformly mixing ammonia water to obtain a sol; S2, sealing and standing the sol in a mold to obtain a wet gel; S3, immersing the wet gel in a nickel solution, sealing and aging, performing supercritical extraction and drying, and then calcining, so that the nickel-based aerogel catalyst is obtained. In the catalyst prepared by the application, active nanoparticles are uniformly dispersed in the mesoporous channels of the aerogel carrier, and the confinement effect of the channel wall effectively inhibits the aggregation of the active nanoparticles, thereby reducing the generation of carbon deposition and improving the stability of the catalyst. Meanwhile, the aerogel itself has a very low thermal conductivity, can effectively avoid the loss of heat, can form a local high temperature near the active site, reduce the reaction barrier, and thus promote the methane dry reforming reaction.

Description

Technical Field

[0001] This invention belongs to the field of energy materials technology, specifically relating to a nickel-based aerogel catalyst, its preparation method, and its application. Background Technology

[0002] The pace of global industrialization is accelerating, and with the widespread use of fossil fuels such as coal, oil, and natural gas, the greenhouse effect is becoming increasingly severe. Carbon dioxide and methane are the two largest greenhouse gases emitted globally, accounting for 79% and 11% of total greenhouse gas emissions, respectively. Methane's greenhouse effect is 22 times that of carbon dioxide, and its emissions are increasing year by year, making the development of effective energy-saving and emission-reduction technologies particularly important.

[0003] Methane dry reforming can simultaneously convert methane and carbon dioxide, two greenhouse gases, to produce syngas in a 1:1 ratio of H2 and CO. This syngas can be directly used as a raw material for Fischer-Tropsch synthesis and hydroxyl synthesis, thus possessing significant research value. However, since CO2 and CH4 are both very stable molecules, with extremely high dissociation energies of 439.3 kJ / mol for the CH bond and 750.0 kJ / mol for C=O, thermocatalysis often requires temperatures above 800 °C to drive the reaction. This not only increases energy consumption but also easily leads to catalyst sintering and deactivation due to excessively high temperatures. With the increasing advantages of photocatalysis, research has found that introducing light into methane dry reforming can lower the reaction temperature, prevent catalyst sintering, improve its stability, and to some extent inhibit the formation of coke deposits and the reverse coal-water reaction, thereby improving catalytic selectivity.

[0004] Currently, supported metal catalysts are the most widely used choice for methane dry reforming catalysts. Noble metals such as Au, Pt, Rh, Ru, and Ir exhibit excellent catalytic performance under light irradiation due to their favorable local surface plasmon resonance effect; however, their high cost limits their practical industrial application. Nickel-based catalysts have attracted considerable attention due to their low cost and high efficiency. However, nickel-based catalysts are prone to carbon deposition and sintering at high temperatures, leading to catalyst deactivation. Therefore, current research focuses on how to effectively reduce the instability of nickel-based catalysts during the reaction process.

[0005] Aerogels, as macroscopic porous materials, possess low thermal conductivity, large specific surface area, and high porosity, and are widely used in adsorption, catalysis, energy, and environmental fields. Loading catalytic materials onto aerogel supports not only preserves their rich pore structure and large specific surface area, but also improves the dispersibility of catalytic components and accelerates the transfer and adsorption of reactants to active sites. This design fully combines the functions of catalysts with the advantages of aerogels. As the most commonly used aerogel support, SiO2 aerogel has excellent thermal insulation properties, enabling the generation of localized hot spots during reactions, thereby lowering the activation energy and improving catalytic efficiency. Simultaneously, its excellent light transmittance ensures the effective absorption of light energy by the active components.

[0006] Therefore, the present invention aims to develop nickel-based catalysts supported on SiO2 aerogel, in order to achieve better catalytic activity in the dry reforming reaction of methane and provide new ideas for greenhouse gas emission reduction. Summary of the Invention

[0007] The technical problem this invention aims to solve is to address the shortcomings of existing technologies by providing an aerogel photothermal catalyst. In this catalyst, active nanoparticles are uniformly dispersed within the mesoporous channels of a silica aerogel support. The confinement effect of the channel walls effectively inhibits the aggregation of active nanoparticles, thereby significantly reducing carbon deposition and improving catalyst stability. Simultaneously, the aerogel itself has extremely low thermal conductivity, effectively preventing heat loss and creating localized high temperatures near the active sites, lowering the reaction barrier and thus promoting the dry reforming reaction of methane.

[0008] To address the aforementioned technical problems, this invention discloses a method for preparing a nickel-based aerogel catalyst, the specific steps of which are as follows:

[0009] S1. Mix anhydrous ethanol, tetramethoxysilane and dimethylacetamide evenly, then add ammonia water and mix evenly to obtain a sol;

[0010] S2. Seal the sol in a mold and let it stand to obtain a wet gel;

[0011] S3. The wet gel is immersed in a nickel solution, sealed and aged, then subjected to supercritical extraction and drying, and finally calcined to obtain the nickel-based aerogel catalyst.

[0012] In step S1, the mass ratio of anhydrous ethanol, tetramethoxysilane, dimethylacetamide, and ammonia is (1-4):1:(0.1-0.4):0.5.

[0013] Preferably, in step S1, the mass ratio of anhydrous ethanol, tetramethoxysilane, dimethylacetamide and ammonia is 2:1:0.125:0.5.

[0014] In step S3, the nickel solution is an alcoholic solution of nickel nitrate, and the mass fraction of nickel in the nickel solution is 0.2-5 wt%.

[0015] Preferably, in step S3, the nickel solution contains 0.5 wt% nickel.

[0016] In step S3, the mass ratio of the wet gel to the nickel solution is 1:(3-5); the aging process takes 4-6 days.

[0017] Preferably, in step S3, the mass ratio of the wet gel to the nickel solution is 1:4; and the aging process takes 5 days.

[0018] In step S3, the drying conditions of the supercritical extraction equipment are: critical temperature of 45℃, critical pressure of 9-13MPa, supercritical fluid CO2, CO2 flow rate of 22L / h, and drying time of 7-15h.

[0019] Preferably, in step S3, the drying conditions of the supercritical extraction equipment are: critical temperature of 45°C, critical pressure of 10MPa, supercritical fluid CO2, CO2 flow rate of 22L / h, and drying time of 13h.

[0020] In step S3, the calcination conditions are as follows: a mixed gas of 10% H2 and 90% Ar is introduced at a flow rate of 50 ml / min, which is then adjusted to 20 ml / min after 10 min; the heating rate is 10 °C / min; and the gas is calcined at 700 °C for 2 h.

[0021] Specifically, in some embodiments of the present invention, nickel-based aerogel catalysts are prepared by the above preparation method;

[0022] The nickel-based aerogel catalyst uses silica as the aerogel support, and the loading of metallic nickel in the nickel-based aerogel catalyst is 0.53 to 10.48 wt%.

[0023] Preferably, the nickel-based aerogel catalyst has a nickel loading of 1.26 wt%.

[0024] Specifically, in some embodiments of the present invention, the application prospects of the nickel-based aerogel catalyst in the dry reforming reaction of methane were verified by evaluating the catalytic activity of the above-mentioned nickel-based aerogel catalyst in a fixed-bed reactor under xenon lamp irradiation.

[0025] Beneficial effects: 1) The aerogel catalyst of the present invention has a large average specific surface area and mesopores with an average pore size of 20-40 nm, which can improve the dispersibility of nickel-based catalysts, increase the contact sites of reactants, accelerate the transfer of reactants and adsorption to active sites, thereby improving the catalytic activity of the material.

[0026] 2) The present invention uses supercritical drying in the preparation process, which avoids the problem of porous structure damage caused by liquid surface tension in the traditional drying process. The complete mesoporous channels confine the nickel nanoparticles, so that the catalyst has good resistance to carbon deposition and sintering, and improves the stability of the catalyst.

[0027] 3) The aerogel monolithic catalyst of the present invention has better catalytic performance than traditional powder catalysts.

[0028] 4) The SiO2 aerogel used in this invention is a macroscopic support for the catalyst, which has good light transmittance and is beneficial to improving the utilization rate of light by the active metal during the catalytic process. Detailed Implementation

[0029] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0030] Example 1: Effect of aerogel raw material component ratio on aerogel structure

[0031] (1) Weigh 4g of tetramethoxysilane, and then weigh the corresponding masses of anhydrous ethanol, dimethylacetamide and ammonia water according to the following mass ratios;

[0032]

[0033] Add half of the weighed anhydrous ethanol, tetramethoxysilane, and dimethylacetamide to a 50 ml beaker and stir at 200 rpm for 5 min to obtain solution A; add the remaining half of the anhydrous ethanol and dilute ammonia (0.16 wt%) to a 50 ml beaker and stir at 200 rpm for 5 min to obtain solution B.

[0034] (2) After mixing the two solutions evenly, slowly add solution B to solution A, stir at 200 r / min for 5 min to hydrolyze, then transfer the sol into the mold and seal it. Let it stand for 1 h to form a wet gel.

[0035] (3) Weigh 1.579g Ni(NO3)2·6H2O and add it to 30g anhydrous ethanol and stir until completely dissolved. Take 7.5g of wet gel and immerse it in it. Seal and age for more than 5 days to ensure that the solvent in the wet gel is fully replaced.

[0036] (4) The aged wet gel was immersed in an ethanol atmosphere and placed in a supercritical extraction device. Gas was introduced slowly, and the parameters in the drying vessel were adjusted to a temperature of 45℃, a pressure of 10MPa, a CO2 flow rate of 22L / h, and a circulation time of 13h.

[0037] (5) The dried aerogel was placed in a tube furnace and 10% H2 with Ar was introduced at a flow rate of 50 ml / min. After 10 min, the flow rate was adjusted to 20 ml / min. The heating rate was 10 °C / min. The aerogel was calcined and reduced at 700 °C for 2 h to obtain the nickel silicate aerogel catalyst.

[0038] In this embodiment, tetramethoxysilane is used as the silicon source for the silica aerogel, and dimethylacetamide is used as a drying control agent. These components strengthen the aerogel framework and homogenize the three-dimensional network. Table 1 shows the effect of different component ratios on the aerogel structure. The porosity was determined using the Biochemical Emission Spectrometry (BET) method. Regularly shaped samples were selected, their volume v was measured, and their mass m was obtained using a precision balance. The sample density ρ = m / v was calculated. Table 1 shows that the higher the mass ratio of the silicon source, the denser the resulting aerogel structure, the higher the density, and the lower the porosity. However, if the mass ratio of the silicon source is too low, the gelation time will be too long, resulting in a loose aerogel framework that is prone to cracking and breakage. Therefore, the preferred mass ratio of anhydrous ethanol, tetramethoxysilane, dimethylacetamide, and ammonia is 2:1:0.125:0.5.

[0039] Table 1. Effect of different group proportions on aerogel structure

[0040]

[0041]

[0042] Example 2: Effect of supercritical drying cycle time on aerogel catalysts

[0043] According to Example 1, the mass ratio of anhydrous ethanol, tetramethoxysilane, dimethylacetamide and ammonia was controlled to be 2:1:0.125:0.5.

[0044] (1) Add 4g of anhydrous ethanol, 4g of tetramethoxysilane and 0.5g of dimethylacetamide to a 50ml beaker and stir at 200r / min for 5min to make solution A; add 4g of anhydrous ethanol and 2g of dilute ammonia (0.16wt%) to a 50ml beaker and stir at 200r / min for 5min to make solution B.

[0045] (2) After mixing the two solutions evenly, slowly add solution B to solution A, stir at 200 r / min for 5 min to hydrolyze, then transfer the sol into the mold and seal it. Let it stand for 1 h to form a wet gel.

[0046] (3) Weigh 1.579g Ni(NO3)2·6H2O and add it to 30g anhydrous ethanol and stir until completely dissolved. Take 7.5g of wet gel and immerse it in it. Seal and age for more than 5 days to ensure that the solvent in the wet gel is fully replaced.

[0047] (4) The aged wet gel was immersed in an ethanol atmosphere and placed in a supercritical extraction device. Gas was introduced slowly, and the parameters inside the drying vessel were adjusted to a temperature of 45℃, a pressure of 10MPa, a CO2 flow rate of 22L / h, and the circulation time was controlled to 7, 9, 11, 13 and 15h respectively.

[0048] (5) The dried aerogel was placed in a tube furnace and 10% H2 with Ar was introduced at a flow rate of 50 ml / min. After 10 min, the flow rate was adjusted to 20 ml / min. The heating rate was 10 °C / min. The aerogel was calcined and reduced at 700 °C for 2 h to obtain the nickel silicate aerogel catalyst.

[0049] The catalysts prepared with different drying cycle times were evaluated for catalytic activity. The specific evaluation method was as follows:

[0050] Weigh 42 mg of aerogel catalyst and load it into a fixed-bed reactor. Introduce H2 (flow rate 20 ml / min), and after venting for half an hour, start the reactor heating program (heating rate 10 °C / min). Reduce the catalyst for 1 hour after reaching 700 °C. After natural cooling to room temperature, introduce a mixed reaction gas of CH4 / CO2 = 1:1 (volume ratio) (flow rate 20 ml / min), vent for half an hour, and after stabilization, restart the heating process (heating rate 10 °C / min). Stabilize the temperature for 5 minutes after reaching 700 °C, then turn on the xenon lamp; the light intensity is 3.7 W / cm². 2 After stabilizing for another five minutes, the product was measured and detected by online gas chromatography.

[0051] Table 2 shows the catalytic performance test results of catalysts prepared at different drying times. As can be seen from Table 2, the longer the drying time, the more complete the structure, the larger the specific surface area of ​​the aerogel catalyst, and the higher the conversion rate and yield during the catalytic reaction. The performance of catalysts dried for 13 h and 15 h is similar, indicating that the drying was thorough and the gel structure was intact. Considering economic factors, a drying time of 13 h is optimal.

[0052] Table 2. Catalytic performance test results of catalysts prepared at different drying times.

[0053]

[0054] Example 3: Effect of critical pressure of supercritical drying on aerogel catalysts

[0055] (1) Add 4g of anhydrous ethanol, 4g of tetramethoxysilane and 0.5g of dimethylacetamide to a 50ml beaker and stir at 200r / min for 5min to make solution A; add 4g of anhydrous ethanol and 2g of dilute ammonia (0.16wt%) to a 50ml beaker and stir at 200r / min for 5min to make solution B.

[0056] (2) After mixing the two solutions evenly, slowly add solution B to solution A, stir at 200 r / min for 5 min to hydrolyze, then transfer the sol into the mold and seal it. Let it stand for 1 h to form a wet gel.

[0057] (3) Weigh 1.579g Ni(NO3)2·6H2O and add it to 30g anhydrous ethanol and stir until completely dissolved. Take 7.5g of wet gel and immerse it in it. Seal and age for more than 5 days to ensure that the solvent in the wet gel is fully replaced.

[0058] (4) The aged wet gel was immersed in an ethanol atmosphere and placed in a supercritical extraction device. Gas was introduced slowly, and the parameters inside the drying vessel were adjusted to a temperature of 45°C, pressures of 9, 10, 11, 12 and 13 MPa, CO2 flow rate of 22 L / h, and circulation time of 13 h.

[0059] (5) The dried aerogel was placed in a tube furnace and 10% H2 with Ar was introduced at a flow rate of 50 ml / min. After 10 min, the flow rate was adjusted to 20 ml / min. The heating rate was 10 °C / min. The aerogel was calcined and reduced at 700 °C for 2 h to obtain the nickel silicate aerogel catalyst.

[0060] The performance of catalysts prepared at different critical pressures was tested. Table 3 shows the test results. As can be seen from Table 3, increasing the critical pressure causes partial rupture of the aerogel framework, resulting in a decrease in conversion rate and deterioration of performance during the catalytic reaction. Conversely, excessively low critical pressures lead to incomplete miscibility between supercritical carbon dioxide and ethanol, incomplete drying, and damage to the aerogel structure, further reducing efficiency. In conclusion, a critical pressure of 10 MPa is optimal.

[0061] Table 3. Performance test results of catalysts prepared at different critical pressures.

[0062]

[0063] Example 4: Effect of Ni loading on aerogel catalyst

[0064] (1) Add 4g of anhydrous ethanol, 4g of tetramethoxysilane and 0.5g of dimethylacetamide to a 50ml beaker and stir at 200r / min for 5min to make solution A; add 4g of anhydrous ethanol and 2g of dilute ammonia (0.16wt%) to a 50ml beaker and stir at 200r / min for 5min to make solution B;

[0065] (2) After mixing the two solutions evenly, slowly add solution B to solution A, stir at 200 r / min for 5 min to hydrolyze, then transfer the sol into the mold and seal it. Let it stand for 1 h to form a wet gel.

[0066] (3) Weigh 0.303g, 0.769g, 1.579g, 3.33g and 10g Ni(NO3)2·6H2O respectively and add them to 30g anhydrous ethanol and stir until completely dissolved. Take 7.5g of wet gel and immerse it in it. Seal and age for more than 5 days to ensure that the solvent in the wet gel is fully replaced.

[0067] (4) The aged wet gel was immersed in an ethanol atmosphere and placed in a supercritical extraction device. Gas was introduced slowly, and the parameters in the drying vessel were adjusted to a temperature of 45℃, a pressure of 10MPa, a CO2 flow rate of 22L / h, and a circulation time of 13h.

[0068] (5) The dried aerogel was placed in a tube furnace and 10% H2 with Ar was introduced at a flow rate of 50 ml / min. After 10 min, the flow rate was adjusted to 20 ml / min. The heating rate was 10 °C / min. The aerogel was calcined and reduced at 700 °C for 2 h to obtain the nickel silicate aerogel catalyst.

[0069] The effect of different Ni loadings on the performance of aerogel catalysts was tested. Table 4 shows the performance evaluation results of catalysts with different Ni loadings. The Ni loadings were determined by ICP-OES characterization. As can be seen from Table 4, changes in catalyst loading significantly affect its activity. The catalytic performance is optimal at a loading of 1.26 wt%, and worst at the highest loading. This is mainly because higher loadings lead to the collapse of aerogel channels, shrinkage of the overall size, and even cracking, thereby reducing catalytic activity and stability. Conversely, lower loadings better maintain the pore structure of the aerogel, preserving catalytic activity and stability. The reason why the catalytic activity of 1.26 wt% loading is better than that of 0.53 wt% is that lower loadings reduce the catalyst's ability to absorb light, resulting in lower light energy utilization, and also reduce the number of reactive sites, leading to a certain degree of decrease in catalytic efficiency.

[0070] Table 4 Performance evaluation results of catalysts with different Ni loadings

[0071]

[0072] Example 5: Stability evaluation of aerogel photothermal catalyst

[0073] (1) Add 4g of anhydrous ethanol, 4g of tetramethoxysilane and 0.5g of dimethylacetamide to a 50ml beaker and stir at 200r / min for 5min to make solution A; add 4g of anhydrous ethanol and 2g of dilute ammonia (0.16wt%) to a 50ml beaker and stir at 200r / min for 5min to make solution B;

[0074] (2) After mixing the two solutions evenly, slowly add solution B to solution A, stir at 200 r / min for 5 min to hydrolyze, then transfer the sol into the mold and seal it. Let it stand for 1 h to form a wet gel.

[0075] (3) Weigh 1.579g Ni(NO3)2·6H2O and add it to 30g anhydrous ethanol and stir until completely dissolved. Take 7.5g of wet gel and immerse it in it. Seal and age for more than 5 days to ensure that the solvent in the wet gel is fully replaced.

[0076] (4) The aged wet gel was immersed in an ethanol atmosphere and placed in a supercritical extraction device. Gas was introduced slowly, and the parameters in the drying vessel were adjusted to a temperature of 45℃, a pressure of 10MPa, a CO2 flow rate of 22L / h, and a circulation time of 13h.

[0077] (5) The dried aerogel was placed in a tube furnace and 10% H2 with Ar was introduced at a flow rate of 50 ml / min. After 10 min, the flow rate was adjusted to 20 ml / min. The heating rate was 10 °C / min. The aerogel was calcined and reduced at 700 °C for 2 h to obtain the nickel silicate aerogel catalyst.

[0078] The stability of the aerogel photothermal catalyst prepared in this embodiment was evaluated using the following method: The aerogel catalyst was loaded into a fixed-bed reactor, H2 was introduced (flow rate 20 ml / min), and after venting for half an hour, the reactor heating program was started (heating rate 10 °C / min), and reduction was carried out for 1 hour after reaching 700 °C. After natural cooling to room temperature, a mixed reaction gas of CH4 / CO2 = 1:1 (volume ratio) was introduced (flow rate 20 ml / min), and after venting for half an hour, the temperature was raised again (heating rate 10 °C / min), and after reaching 700 °C and stabilizing for 5 minutes, the xenon lamp was turned on, with a light intensity of 3.7 W / cm². 2 After stabilizing for another five minutes, the product was measured continuously for 12 hours. The product was then analyzed and detected by online gas chromatography.

[0079] Table 5 shows the stability evaluation results of the catalyst prepared in this embodiment. As can be seen from Table 5, the conversion rate of the catalyst hardly decreased after 12 hours of continuous operation, which reflects good stability.

[0080] Table 5. Catalyst stability evaluation results in Example 5

[0081]

[0082] Comparative Example 1: Effect of light on the performance of aerogel catalysts

[0083] The preparation of the aerogel photothermal catalyst is the same as in Example 5, except that the xenon lamp is not turned on during the catalytic activity evaluation.

[0084] The performance test results of the aerogel photothermal catalysts prepared in Example 5 and Comparative Example 1 are shown in Table 6:

[0085] Table 6. Performance evaluation results of the catalysts in Example 1 and Comparative Example 1

[0086]

[0087] As shown in Table 6, with the same catalyst at a reaction temperature of 700℃, the photothermal catalysis efficiency in Example 5 is significantly greater than that in Comparative Example 1, and the H2 / CO ratio is also higher. This indicates that the introduction of light energy can lower the reaction activation energy, greatly improve catalytic efficiency, and inhibit the reverse coal-water reaction, thereby improving catalytic selectivity. Comparative Example 2: Comparison of the performance of site-exposed catalysts and aerogel catalysts.

[0088] The preparation steps for site-exposed catalysts are as follows:

[0089] (1) Dissolve 124 mg Ni(NO3)2·6H2O in 25 mL of deionized water to obtain a Ni precursor salt solution;

[0090] (2) Disperse 500 mg of SiO2 powder in 25 mL of deionized water and sonicate for 15 min;

[0091] (3) During rapid stirring, add the solution from step (1) dropwise to the solution from step (2);

[0092] (4) Stir in an oil bath at 80°C until all moisture is removed, then place the sample in an oven at 105°C and dry overnight.

[0093] (5) Grind the dried sample for 10 min, then place it in a muffle furnace and calcine it at 450 °C for 2 h at a heating rate of 2 °C / min to obtain a nickel oxide catalyst.

[0094] (6) Finally, the sample was placed in a tube furnace and heated to 700°C for 2 hours under a hydrogen atmosphere at a heating rate of 10°C / min to obtain a site-exposed catalyst.

[0095] The performance of the catalysts prepared in Example 5 and Comparative Example 2 was tested. Table 7 shows the performance evaluation results for both. As can be seen from Table 7, both Example 5 and Comparative Example 2 used nickel as the active metal and SiO2 as the support. When the support was in the form of aerogel, the performance of the catalyst was significantly improved.

[0096] Table 7 Performance evaluation results of the catalysts in Example 5 and Comparative Example 2

[0097]

[0098] This invention provides a method for preparing a nickel-based aerogel catalyst and its application. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A method for preparing a nickel-based aerogel catalyst, characterized by, The specific steps are as follows: S1. mixing anhydrous ethanol, tetramethoxysilane and dimethylacetamide uniformly, then adding ammonia water and mixing uniformly to obtain a sol; S2. sealing and standing the sol in a mold to obtain a wet gel; S3. immersing the wet gel in a nickel solution, sealing and aging, then performing supercritical extraction drying, and then calcining to obtain the nickel-based aerogel catalyst; In step S3, the supercritical extraction drying conditions are: critical temperature 45℃, critical pressure 10MPa, supercritical fluid CO2, CO2 flow rate 22L / h, and drying time 13h; The nickel solution is an alcohol solution of nickel nitrate, and the mass fraction of nickel in the nickel solution is 0.5wt%.

2. The production method according to claim 1, characterized by, In step S1, the mass ratio of anhydrous ethanol, tetramethoxysilane, dimethylacetamide and ammonia water is (1-4):1:(0.1-0.4):0.

5.

3. The preparation method according to claim 1, characterized in that, In step S3, the mass ratio of the wet gel to the nickel solution is 1:(3-5), and the sealing and aging time is 4-6d.

4. The method of claim 1, wherein, In step S3, the calcination is performed in a reducing atmosphere, and the conditions are: flowing a mixture of 10%H2 and 90%Ar at a flow rate of 50ml / min, adjusting to 20ml / min after 10min, heating rate 10℃ / min, calcining at 700℃ for 2h.

5. The nickel-based aerogel catalyst prepared by the preparation method of any one of claims 1-4.

6. The nickel-based aerogel catalyst of claim 5, wherein, The nickel-based aerogel catalyst uses silica as an aerogel carrier, and the loading amount of metallic nickel in the nickel-based aerogel catalyst is 0.53-10.48wt%.

7. The nickel-based aerogel catalyst of claim 5 is used in a methane dry reforming reaction.

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