An ultra-thin defect-rich nickel phyllosilicate catalyst and its preparation method and application

Abstract

The present invention discloses a preparation method and application of an ultrathin defect-rich nickel phyllosilicate catalyst, belonging to the technical field of inorganic nanomaterial preparation. The present invention adds a certain proportion of a soluble nickel salt (nickel source), a silicon oxide material (silicon source), and a certain amount of a fluorine-containing etchant and an alkaline substance, a pore-forming agent, and a defoaming agent to a microwave oven. By adjusting parameters such as microwave power, heating time, and the nickel-silicon ratio, the ultrathin defect-rich nickel phyllosilicate catalyst is rapidly and efficiently synthesized. Compared with catalysts prepared by traditional hydrothermal and ammonia distillation methods, the catalyst prepared by the method of the present invention has the advantages of being green and environmentally friendly, having mild preparation conditions, a short cycle, a thin nickel phyllosilicate layer with many defect sites, and high catalytic activity.

Description

Technical Field

[0001] The present invention belongs to the technical field of inorganic nanomaterial preparation, and specifically relates to a method for preparing an ultra-thin defect-rich nickel phyllosilicate catalyst. The catalyst can be used for CO2-CH4 reforming to produce synthesis gas reaction and CO methanation reaction. Background Art

[0002] Nickel phyllosilicate (NIP) has been widely used in a variety of technologies, including catalysis, batteries, optoelectronic materials, and energy storage, due to its advantages, such as its ordered lamellar structure, high specific surface area, and excellent surface-interface confinement effects. Due to the high crystallinity of the product, the hydrothermal method is a common method for preparing NIP. The specific process involves water etching silicon oxide to form an orthosilicic acid intermediate. The hydroxyl radicals generated by the water ionization combine with nickel ions to form nickel hydroxide. The resulting orthosilicic acid intermediate and nickel hydroxide then react to produce NIP. This method has disadvantages, such as high hydrothermal reaction temperatures (>150°C) and long hydrothermal times (>16 hours) (Patent Application Publication No. CN 111017940 A). Below these stringent hydrothermal conditions, NIP catalysts are difficult to synthesize hydrothermally. To this end, a hydrothermal method based on a dual-accelerator improvement (patent application publication number CN 112221503 A) promotes the formation of orthosilicic acid intermediates and nickel hydroxide by adding a fluorine-based silicon oxide etchant and an alkaline substance. This allows the hydrothermal reaction to proceed at temperatures between 40 and 120°C, enabling the preparation of nickel phyllosilicate catalysts at lower hydrothermal temperatures and in shorter hydrothermal times. Both the traditional hydrothermal method and the improved dual-accelerator hydrothermal method transfer heat from the outside to the material based on the principles of heat conduction, convection, and radiation. Heat is always transferred from the outside to the inside to heat the material, inevitably resulting in temperature gradients within the material. This results in uneven heating of the material, leading to localized overheating and thus hindering the reaction. Summary of the Invention

[0003] To overcome the problems of localized overheating and uneven heating of the raw materials during traditional hydrothermal methods, the present invention provides a microwave-assisted method for preparing ultrathin, defect-rich nickel phyllosilicate catalysts. This method addresses the uneven heating issues encountered by traditional hydrothermal methods. This method operates under mild conditions (room temperature and atmospheric pressure), is environmentally friendly and pollution-free, has a shorter preparation cycle (as little as one minute), and can produce ultrathin, defect-rich nickel phyllosilicate catalysts with enhanced catalytic performance.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for preparing an ultra-thin defect-rich nickel phyllosilicate catalyst comprises the following steps:

[0006] (1) At room temperature, a mixed solution containing a soluble nickel salt, a fluorine-containing etchant, and an alkaline substance is prepared with deionized water, and a silicon oxide material, a pore-forming agent, and a defoaming agent are added to the mixed solution, and the mixture is stirred and dispersed uniformly to obtain a green mixed solution;

[0007] (2) Transfer the green mixed solution to a microwave oven and fully react it at a microwave intensity of 70 to 700 W for 1 to 10 minutes;

[0008] (3) After the microwave is finished, the solution is washed, dried, and calcined to obtain nickel phyllosilicate.

[0009] Specifically, in step (3), after the microwave treatment is completed, the solution is washed, dried at 60° C., and calcined in an air atmosphere at 400-600° C. for 2 hours to obtain nickel phyllosilicate.

[0010] Furthermore, the soluble nickel salt includes but is not limited to a mixture of one or more of nickel nitrate, nickel chloride, nickel sulfate, nickel acetylacetonate, nickel acetate or hydrates thereof.

[0011] Furthermore, the fluorine-containing etchant reacts with silicon dioxide to generate orthosilicic acid, and compared with water as an etchant, the fluorine-containing etchant can promote the generation of orthosilicic acid. The fluorine-containing etchant includes but is not limited to a mixture of one or more of fluorosilicic acid, fluorooxy acid, fluoroantimonic acid, ammonium fluoride, ammonium bifluoride, ammonium hexafluorosilicate, fluoroboric acid, and nonafluoropentanoic acid.

[0012] The alkaline substance can accelerate the generation of nickel hydroxide, and the alkaline substance includes but is not limited to a mixture of one or more of hexamethylenetetramine, formamide, ammonium carbonate, urea, sodium hydroxide and potassium hydroxide.

[0013] The pore-forming agent can generate gas during the microwave reaction, forming defects on the surface of the nickel phyllosilicate due to cavitation. The pore-forming agent includes, but is not limited to, a basic pore-forming agent (such as ammonium carbonate), a neutral pore-forming agent (such as hydrogen peroxide), an acidic pore-forming agent (such as ammonium formate), or a mixture of one or more metal peroxides that generate gas upon heating (such as sodium peroxide and potassium peroxide).

[0014] Due to cavitation, bubbles are too numerous to overflow during the reaction, so a defoamer is added to eliminate the excess bubbles and ensure a stable reaction. The defoamer includes but is not limited to one or more mixtures of P123, F127, ethylene glycol dimethyl ether, and p-hydroxyanisole.

[0015] Furthermore, as described in publication number CN112221503A, the silicon oxide material can be natural amorphous silicon oxide (such as diatomaceous earth), can be an artificially synthesized mesoporous silicon oxide material (SBA-15, MCM-41, MCF, FDU-12, etc.), can be extracted and prepared from silicon-containing industrial solid waste (iron tailings, silicon micropowder, yellow phosphorus slag, oil shale ash, etc.) or biomass waste (vinasse, vinegar dregs, rice husks, straw, etc.), or commercially available amorphous silicon oxide can be directly used.

[0016] Furthermore, the molar ratio of the deionized water to the soluble nickel salt is 30:1 to 10:1; and the molar ratio of the silicon oxide material to the soluble nickel salt is 1:3 to 5:3.

[0017] Furthermore, the molar ratio of the fluorine-containing etchant to the silicon oxide material is 1:5 to 1:10; the molar ratio of the alkaline substance to the silicon oxide material is 2:1 to 1:5; the molar ratio of the pore-forming agent to the silicon oxide material is 1:10 to 1:15; and the molar ratio of the pore-forming agent to the defoaming agent is 2:1 to 5:1.

[0018] The catalyst can be used in CO2-CH4 dry reforming to produce synthesis gas reaction and CO methanation reaction.

[0019] The following briefly describes the principle of the invention's successful preparation of ultra-thin defect-rich nickel silicate using fluorine-containing etchant fluoroantimonic acid, alkaline substance formamide, and pore-forming agent hydrogen peroxide as examples:

[0020] (a) Etching of silicon oxide

[0021] SiO2+2HSbF6+7H2O→H4SiO4+Sb2O5+12HF

[0022] (b) Decomposition of formamide and formation of nickel hydroxide

[0023] HCONH2+H2O+OH - →NH3·H2O+HCOO -

[0024] Ni 2+ +2NH3·H2O→Ni(OH)2+2NH4 +

[0025] (c) Formation of Nickel Phyllosilicate

[0026] 3Ni(OH)2+2H4SiO4→Ni3Si2O5(OH)4+5H2O

[0027] (d) Generation of defective bits

[0028] The O2 generated by 2H2O2→2H2O+O2 etches and creates holes, resulting in defects.

[0029] It is worth noting that according to the simulation results of the multi-physics field coupling simulation software Comsol 5.6, the instantaneous temperature of microwaves on the Teflon lining wall can reach 220°C, and the overall temperature inside the reactants is between 40 and 80°C, with a uniform temperature distribution. The synthesis of phyllosilicate nickel is formed under such instantaneous high temperature conditions.

[0030] In the formation process of nickel phyllosilicate, both fluorine-containing etchants and alkaline substances play a crucial role: first, the significant etching effect of fluoroantimonic acid makes silicon oxide more likely to generate orthosilicic acid (reaction a), accelerating the generation rate of orthosilicic acid; secondly, the NH3·H2O produced by the hydrolysis of formamide promotes the reaction with Ni 2+ The reaction generates Ni(OH)2 (reaction b), and finally the orthosilicic acid and Ni(OH)2 generate Ni3Si4O 10 (OH)2 (reaction c). Defects are generated by the decomposition of hydrogen peroxide to produce O2, which creates pores in the nickel phyllosilicate sheets (reaction d). The defoamer acts by utilizing the "bridging-stretching" mechanism of polymer chains. The surface tension of polyether substances is much lower than that of the liquid film, allowing the defoamer droplets to continuously spread and penetrate the liquid film surface. The local liquid film of the foam continues to thin, eventually forming an oil-water bridge. The surface tensions of the oil and water phases differ greatly. The oil phase is continuously pulled by the surrounding water phase, stretching and thinning. After the deformation exceeds a certain range, the liquid film is destroyed, causing the foam to burst, thereby preventing boiling caused by excessive reaction of the solution. In summary, the fluorine-containing etchant and alkaline substances promote the formation of two nickel phyllosilicate intermediates, orthosilicic acid and Ni(OH)2, respectively, while hydrogen peroxide, as a chemical etchant, promotes the formation of defect sites. The addition of the defoamer can suppress boiling caused by excessive reaction of the solution. In short, these are necessary conditions for the formation of nickel phyllosilicate under mild conditions.

[0031] Microwaves have distinct characteristics, including short wavelengths (1m to 1mm), high frequencies (300MHz to 300GHz), and quantum properties. Microwave heating relies on an object's absorption of microwave energy, converting it into heat, which simultaneously heats the entire object, making it distinct from other conventional heating methods. Microwave heating technology differs from conventional heating methods in that it raises the temperature of the material through the high-frequency reciprocating motion of dipole molecules within the heated object, generating "internal frictional heat." This heats the material both internally and externally, without requiring any heat conduction. Heating is rapid and uniform, requiring only a fraction or even a few tenths of the energy consumed by conventional heating methods. Due to the short reaction time and uniform heat distribution, small, ultrathin nickel phyllosilicates are produced. The addition of a pore-forming agent acts as a chemical etchant, creating pores within the nickel phyllosilicate. This etched-out layer can be etched with numerous defects (steps, terraces, edges, corners, kinks, stacking faults, etc.), ultimately yielding ultrathin, defect-rich nickel phyllosilicates. During the microwave reaction, the silicon-based material is continuously consumed as a sacrificial template, and phyllosilicate nucleates, forms, and grows on its surface. The promoter can accelerate the growth and form pores. The whole process involves the diffusion, mass transfer, and reaction of multiple atoms.

[0032] The method of the present invention has simple process and is easy to operate. The method can not only obtain ultra-thin defect-rich nickel phyllosilicate, but also has very uniform particle size distribution of nano nickel particles after reduction.

[0033] Compared with the prior art, the present invention has the following advantages: nickel phyllosilicate can be synthesized at room temperature and normal pressure, the preparation conditions are milder, the preparation cycle is shorter, the obtained sample thickness is small, the activity is high, the crystallinity is high, and the nickel phyllosilicate sheet has a large number of defect sites, which greatly improves the metal utilization rate, i.e., the catalytic performance; (4) the preparation method is simple, the microwave oven used is a common equipment, the production cost is low, and it is easy to mass-produce. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is the XRD pattern of nickel phyllosilicate prepared in Example 3 of the present invention.

[0035] Figure 2 This is an SEM image of nickel phyllosilicate prepared in Example 3 of the present invention.

[0036] Figure 3 This is a TEM image of the nickel phyllosilicate prepared in Example 3 of the present invention after hydrogen reduction.

[0037] Figure 4 This is an AFM image of nickel phyllosilicate prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments.

[0039] Example 1

[0040] Nickel nitrate, fluorosilicic acid, and formamide were weighed and dissolved in deionized water (molar ratio of 1:0.2:0.5:20). FDU-12 was stirred and evenly dispersed in the above solution at 20°C (molar ratio of nickel nitrate to FDU-12 was 3:5). Hydrogen peroxide (1 mL) and P123 (1 g) were then added. The green mixture was then transferred to a microwave oven and reacted at 560 W for 5 minutes. After the reaction, the mixture was washed with deionized water, centrifuged, dried at 60°C, and finally calcined at 400°C in air for 2 hours to obtain ultrathin defect-rich nickel phyllosilicate.

[0041] Example 2

[0042] Nickel chloride, fluoroantimonic acid, and hexamethylenetetramine were weighed and dissolved in deionized water (molar ratio of 1:0.4:1:10). SBA-15 was stirred and evenly dispersed in the above solution at 20°C (molar ratio of nickel chloride to SBA-15 was 3:1). Formamide (2 mL) and F127 (2 g) were added, and the green mixture was transferred to a microwave oven and reacted at a microwave power of 700 W for 1 minute. After the reaction, the mixture was washed with deionized water, centrifuged, dried at 60°C, and finally calcined at 400°C in air for 2 hours to obtain ultrathin defect-rich nickel phyllosilicate.

[0043] Example 3

[0044] Nickel acetylacetonate, fluorous acid, and formamide were weighed and dissolved in deionized water (molar ratio of 1:0.2:0.6:5). Silicon oxide prepared by the Stober method was stirred and evenly dispersed in the above solution at 20°C (the molar ratio of nickel acetylacetonate to silicon oxide prepared by the Stober method was 3:2). Hydrogen peroxide (1 mL) and ethylene glycol dimethyl ether (1 g) were added, and the green mixture was transferred to a microwave oven and reacted at a microwave power of 560 W for 5 minutes. After the reaction, it was washed with deionized water, centrifuged, dried at 60°C, and finally calcined at 400°C in an air atmosphere for 2 hours to obtain ultra-thin defect-rich nickel phyllosilicate.

[0045] Example 4

[0046] Nickel acetate, fluorosilicic acid, and formamide were weighed and dissolved in deionized water (molar ratio of 1:0.3:0.4:15). Silicon oxide prepared from rice husks was stirred and evenly dispersed in the above solution at 20°C (the molar ratio of nickel acetate to silicon oxide prepared from rice husks was 3:5). Ammonium carbonate (3g) and p-hydroxyanisole (3g) were added, and the green mixture was transferred to a microwave oven and reacted at a microwave power of 350W for 10 minutes. After the reaction, it was washed with deionized water, centrifuged, dried at 60°C, and finally calcined at 400°C in an air atmosphere for 2 hours to obtain ultra-thin defect-rich nickel phyllosilicate.

[0047] Example 5

[0048] Nickel nitrate, fluoroantimonic acid, and hexamethylenetetraammonium were weighed and dissolved in deionized water (molar ratio of 1:0.2:0.5:20). Silica prepared from horsetail was stirred and evenly dispersed in the above solution at 20°C (molar ratio of nickel nitrate to silica prepared from horsetail was 3:4). Ammonium formate (2g) and P123 (2g) were added, and the green mixture was transferred to a microwave oven and reacted at 560W for 5 minutes. After the reaction, the mixture was washed with deionized water, centrifuged, dried at 60°C, and finally calcined at 400°C in air for 2 hours to obtain ultrathin defect-rich nickel phyllosilicate.

[0049] Example 6

[0050] Nickel acetylacetonate, fluorous acid, and formamide were weighed and dissolved in deionized water (molar ratio of 1:0.1:0.1:20). Silicon oxide prepared from rice husks was stirred and evenly dispersed in the above solution at 20°C (the molar ratio of nickel acetylacetonate to silicon oxide prepared from rice husks was 3:1). Sodium peroxide (1g) and F127 (1g) were added, and the green mixture was transferred to a microwave oven and reacted at a microwave power of 560W for 5 minutes. After the reaction, it was washed with deionized water, centrifuged, dried at 60°C, and finally calcined at 400°C in an air atmosphere for 2 hours to obtain ultra-thin defect-rich nickel phyllosilicate.

[0051] Example 7

[0052] Nickel sulfide, fluorosilicic acid, and formamide were weighed and dissolved in deionized water (molar ratio of 1:0.1:0.2:15). Silicon oxide prepared from vinasse was stirred and evenly dispersed in the above solution at 20°C (the molar ratio of nickel sulfide to silicon oxide prepared from vinasse was 3:4). Potassium peroxide (1g) and p-hydroxyanisole (1g) were added, and the green mixture was transferred to a microwave oven and reacted at a microwave power of 560W for 5 minutes. After the reaction, it was washed with deionized water, centrifuged, dried at 60°C, and finally calcined at 400°C in an air atmosphere for 2 hours to obtain ultra-thin defect-rich nickel phyllosilicate.

[0053] Example 8

[0054] This comparative example is the same as Example 3 except that no pore-forming agent and defoaming agent are added. The specific steps are:

[0055] Nickel acetylacetonate, oxyfluoric acid, and formamide were weighed and dissolved in deionized water (molar ratio of 1:0.2:0.6:5). Silicon oxide prepared by the Stober method was stirred and evenly dispersed in the above solution at 20°C (molar ratio of nickel acetylacetonate to silicon oxide prepared by the Stober method was 3:2). The green mixture was then transferred to a microwave oven and reacted at a microwave power of 560W for 5 minutes. After the reaction, the mixture was washed with deionized water, centrifuged, dried at 60°C, and finally calcined in air at 400°C for 2 hours to obtain ultrathin nickel silicate.

[0056] Comparative Example 1

[0057] Nickel acetylacetonate, oxyfluoric acid, and formamide were weighed and dissolved in deionized water (molar ratio of 1:0.2:0.6:5). Silicon oxide prepared by the Stober method was uniformly dispersed in the solution at 20°C (molar ratio of nickel acetylacetonate to silicon oxide prepared by the Stober method was 3:2). After uniform stirring, the mixture was transferred to a hydrothermal reactor and hydrothermaled at 120°C for 24 hours. After cooling to room temperature, the mixture was separated by suction, dried, and calcined to produce nickel phyllosilicate.

[0058] Figure 1 This is the XRD pattern of nickel phyllosilicate prepared in Example 3 of the present invention, and the results prove that the sample is nickel phyllosilicate. Figure 2 This is a SEM image of nickel phyllosilicate prepared in Example 3 of the present invention. The result shows that the morphology is silica microspheres attached to flakes, which is a typical morphology of nickel phyllosilicate. Figure 3 This is a TEM image of the nickel phyllosilicate prepared in Example 3 of the present invention after hydrogen reduction. The results show that a large number of defect structures appear in the nickel phyllosilicate layer after hydrogen peroxide etching. Figure 4 This is an AFM image of the nickel phyllosilicate prepared in Example 3 of the present invention. The results show that the nickel phyllosilicate layer is as thin as 670 μm, which is a typical single-layer structure.

[0059] Catalyst performance evaluation

[0060] Catalytic performance tests were conducted on Examples 1-8 and Comparative Example 1, using the CO methanation reaction as a model reaction. 0.1 g of the 20-40 mesh catalyst was placed in a quartz reaction tube. After hydrogen reduction at 600°C, a mixture of H₂:CO:N₂ (volume flow rate ratio of 3:1:1) was introduced. The reaction was carried out at atmospheric pressure, a mass space velocity of 60,000 mL / h·g, and a temperature of 400°C.

[0061] Table 1 shows the CO conversion rate and CH4 yield of the catalysts in Examples 1-8 and Comparative Example 1 in the CO methanation reaction.

[0062] Table 1

[0063] Serial number CO conversion rate (%) <![CDATA[CH4 selectivity (%)]]> <![CDATA[CH4 production rate (%)]]> Example 1 87 94 82 Example 2 90 91 82 Example 3 97 99 96 Example 4 84 89 75 Example 5 89 92 82 Example 6 86 93 80 Example 7 94 91 86 Example 8 82 90 74 Comparative Example 1 76 85 65

[0064] Catalytic performance tests were conducted on Examples 1-8 and Comparative Example 1, using the CO₂-CH₄ dry reforming reaction to produce synthesis gas as a model reaction. 0.1 g of a 20-40 mesh catalyst was loaded into a quartz reaction tube. After hydrogen reduction at 600°C, a reaction mixture of CO₂:CH₄:N₂ (volume flow rate ratio of 3:3:14) was introduced. The reaction pressure was atmospheric pressure, the mass space velocity was 60,000 mL / h·g, and the reaction temperature was 700°C.

[0065] Table 2 shows the CO2 conversion rate, CH4 conversion rate and H2 / CO ratio of the catalysts in Examples 1-8 and Comparative Example 1 in the CO2-CH4 dry reforming reaction to produce synthesis gas.

[0066] Table 2

[0067] Serial number <![CDATA[CO2 conversion rate (%)]]> <![CDATA[CH4 conversion rate (%)]]> <![CDATA[H2 / CO ratio]]> Example 1 68 85 1.6 Example 2 72 84 1.5 Example 3 88 91 1.0 Example 4 69 80 1.5 Example 5 70 82 1.4 Example 6 75 79 1.5 Example 7 79 82 1.3 Example 8 79 80 1.6 Comparative Example 1 52 71 1.6

[0068] As described above, the ultra-thin defect-rich nickel phyllosilicate catalyst prepared by a microwave method proposed in the present invention has high activity and good application prospects in high-temperature reactions.

[0069] Although the present invention is described herein with reference to illustrative embodiments of the present invention, the above embodiments are merely preferred embodiments of the present invention, and the embodiments of the present invention are not limited to the above embodiments. It should be understood that those skilled in the art can design many other modifications and implementations, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. A method for preparing an ultra-thin defect-rich nickel phyllosilicate catalyst, characterized in that: The following steps are involved: (1) Preparing a mixed solution containing a soluble nickel salt, a fluorine-containing etchant, an alkaline substance, a silicon oxide material, a pore-forming agent, and a defoaming agent; (2) Transfer the mixed solution to a microwave oven for reaction; (3) After the microwave is finished, the solution is washed, dried, and calcined to obtain nickel phyllosilicate; The pore-forming agent is a basic pore-forming agent, a neutral pore-forming agent, an acidic pore-forming agent, or a mixture of one or more metal peroxides that can generate gas when heated; The alkaline pore-forming agent is ammonium carbonate, the neutral pore-forming agent is hydrogen peroxide, the acidic pore-forming agent is ammonium formate, and the metal peroxide is sodium peroxide or potassium peroxide.

2. The method for preparing the ultra-thin defect-rich nickel phyllosilicate catalyst according to claim 1, wherein: In step (2), the mixed solution is transferred to a microwave oven and fully reacted at a microwave intensity of 70 to 700 W for 1 to 10 minutes.

3. The method for preparing the ultra-thin defect-rich nickel silicate catalyst according to claim 1, wherein: In step (3), after the microwave treatment is completed, the solution is washed, dried at 60°C, and calcined in an air atmosphere at 400-600°C for 2 hours to obtain nickel phyllosilicate.

4. The method for preparing the ultra-thin defect-rich nickel silicate catalyst according to claim 1, wherein: The soluble nickel salt is a mixture of one or more of nickel nitrate, nickel chloride, nickel sulfate, nickel acetylacetonate, nickel acetate or their hydrates; the fluorine-containing etchant is a mixture of one or more of fluorosilicic acid, fluorooxyacid, fluoroantimonic acid, ammonium fluoride, ammonium bifluoride, ammonium hexafluorosilicate, fluoroboric acid and nonafluoropentanoic acid.

5. The method for preparing the ultra-thin defect-rich nickel phyllosilicate catalyst according to claim 1, wherein: The alkaline substance is a mixture of one or more of hexamethylenetetramine, formamide, ammonium carbonate, urea, sodium hydroxide and potassium hydroxide.

6. The method for preparing the ultra-thin defect-rich nickel phyllosilicate catalyst according to claim 1, wherein: The defoaming agent is a mixture of one or more of P123, F127, ethylene glycol dimethyl ether and p-hydroxyanisole; the molar ratio of deionized water to soluble nickel salt is 30:1-10:1; the molar ratio of silicon oxide material to soluble nickel salt is 1:3-5:3; the molar ratio of fluorine-containing etchant to silicon oxide material is 1:5-1:10; the molar ratio of alkaline substance to silicon oxide material is 2:1-1:5; the molar ratio of pore-forming agent to silicon oxide material is 1:10-1:15; and the molar ratio of pore-forming agent to defoaming agent is 2:1-5:

1.

7. The catalyst prepared by the method according to any one of claims 1 to 6.

8. Use of the catalyst according to claim 7 in CO2-CH4 dry reforming to produce synthesis gas and CO methanation reaction.

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