A multilayer core-shell structure nickel-based catalyst and preparation method thereof

Abstract

The present invention provides a multi-layer core-shell structure nickel-based catalyst and a preparation method thereof. The multi-layer core-shell structure nickel-based catalyst uses a carrier as a core and auxiliary components and active components as a shell. During the reaction process, on the one hand, the shell layer can block carbon deposition during the reaction process, thereby preventing the carrier from sintering during a high-temperature catalytic reaction, causing the active components of the catalyst to aggregate and deactivate, and improving the catalyst's anti-carbon deposition performance. On the other hand, the auxiliary components or active components form a "shell" on the carrier surface to achieve high dispersion on the carrier surface to expose more active sites. At the same time, the active component and the auxiliary component are closely adjacent to each other, thereby enhancing the electronic synergistic effect between the two and effectively improving the catalyst's carbon deposition problem during the methane reforming process. The multi-layer core-shell structure nickel-based catalyst of the present invention has a stable core-shell structure, excellent catalytic activity and anti-carbon deposition performance, and has important economic value and promotion significance.

Description

Technical Field

[0001] The invention relates to the technical field of catalyst preparation, and in particular to a multi-layer core-shell structure nickel-based catalyst and a preparation method thereof. Background Art

[0002] With the rapid increase in fossil energy consumption and greenhouse gas emissions year by year, the global climate has deteriorated sharply, posing a major threat to the production and life of human society. Therefore, the reduction and conversion of major greenhouse gases such as carbon dioxide (CO2) and methane (CH4) have attracted widespread attention from all over the world. The dry reforming of methane (CH4+CO2→2CO+2H2, dry reforming of methane, abbreviated as DRM) can not only effectively reduce the emissions of two major greenhouse gases, CH4 and CO2, but can also be used to produce synthesis gas with a hydrogen-to-carbon ratio (H2 / CO) of 1.0, which is of great significance for achieving my country's "dual carbon" goals and ensuring energy security.

[0003] The DRM reaction is a typical strongly endothermic reaction that needs to be operated at a relatively high temperature. This causes the catalyst to be easily deactivated due to carbon deposition and sintering at high temperatures. Therefore, the industrial application of this reaction is greatly limited.

[0004] Chinese patent CN104226312B "A core-shell structure catalyst, preparation method and application thereof" discloses a core-shell structure catalyst with nanoparticles of metal active components and nanoparticles of additives as the core and carriers and additives as the shell. However, the core-shell structure of the catalyst is unstable and its catalytic activity still needs to be further improved.

[0005] Therefore, it is of great significance to develop a multilayer core-shell structured nickel-based catalyst with stable core-shell structure and high catalytic activity and a preparation method thereof. Summary of the invention

[0006] In view of the fact that the existing core-shell structure catalysts have an unstable core-shell structure and the catalytic activity still needs to be further improved, the present invention provides a multi-layer core-shell structure nickel-based catalyst and a preparation method thereof, which has a carrier as a core and auxiliary components and active components as a shell, has a stable core-shell structure, excellent catalytic activity and anti-carbon deposition performance, and has important economic value and promotion significance.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] A method for preparing a multilayer core-shell structured nickel-based catalyst comprises the following steps:

[0009] S1. Calculate and weigh the mass of each component according to the target catalyst composition;

[0010] S2. The carrier and the solvent are fully mixed to obtain a carrier solution, and an alkaline solvent is added dropwise to adjust the pH value to the pH range of carrier ion precipitation, stirred, ultrasonicated, and allowed to stand for 4-12 hours to obtain a precursor suspension for standby use;

[0011] S3. The oxygen-conducting rare earth additive and the solvent are fully mixed to obtain an oxygen-conducting rare earth additive solution, which is added dropwise to the precursor suspension obtained in S2 together with the alkaline solution, and the pH value is adjusted to the pH value range of the oxygen-conducting rare earth additive ion precipitation, stirred, ultrasonicated, and allowed to stand for 4-12 hours to obtain a single-layer core-shell catalyst precursor suspension;

[0012] S4. The carbon dioxide adsorption aid and the solvent are fully mixed to obtain a carbon dioxide adsorption aid solution, which is added dropwise to the precursor suspension obtained in S3 together with the alkaline solution, and the pH value is adjusted to the pH value range of carbon dioxide adsorption aid ion precipitation, stirred, ultrasonicated, and allowed to stand for 4-12 hours to obtain a double-layer core-shell structure catalyst precursor suspension;

[0013] S5. The nickel source and the solvent are fully mixed to obtain a nickel solution, which is added dropwise to the precursor suspension obtained in S4 together with the alkaline solution, the pH value is adjusted to the pH range for nickel ion precipitation, stirred, ultrasonicated, allowed to stand for 12-24 hours, and the precipitate is filtered to obtain a multilayer core-shell catalyst precursor;

[0014] S6. calcining and reducing the multi-layer core-shell structure catalyst precursor obtained in S5 to obtain the multi-layer core-shell structure nickel-based catalyst.

[0015] Furthermore, the target catalyst component composition of S1 is: 5-25wt.% nickel, 70-90wt.% carrier, 0.5-5wt.% oxygen-conducting rare earth additive, and 0.5-5wt.% carbon dioxide adsorption additive.

[0016] Furthermore, the carrier in S2 is one or more of aluminum nitrate, aluminum chloride, and zirconium oxychloride.

[0017] Furthermore, the oxygen-conducting rare earth additive described in S3 is cerium nitrate and / or lanthanum nitrate.

[0018] Furthermore, the carbon dioxide adsorption aid described in S4 is one or more of calcium nitrate, calcium acetate, magnesium nitrate, magnesium acetate, potassium nitrate, and potassium acetate.

[0019] Furthermore, the nickel source in S5 is nickel nitrate.

[0020] Furthermore, the solvents in S2, S3, S4 and S5 are independently deionized water or ethanol, and the alkaline solvents in S2, S3, S4 and S5 are independently one or more of ethylenediamine alcohol solution, urea and aqueous ammonia solution.

[0021] Furthermore, the ultrasonic time in S2, S3, S4 and S5 is independently selected from 10-60 min.

[0022] Furthermore, the calcination temperature in S6 is 600-800°C for 4 hours; the reduction is carried out in a H2 atmosphere at a temperature of 700-750°C for 3-5 hours.

[0023] Another object of the present invention is to provide a multi-layer core-shell structured nickel-based catalyst.

[0024] A multi-layer core-shell structured nickel-based catalyst is prepared by any of the above-mentioned preparation methods.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] The multi-layer core-shell structure nickel-based catalyst of the present invention has a carrier as a core, and auxiliary components and active components as a shell. During the reaction process, on the one hand, the shell layer can block carbon deposition during the reaction process, thereby preventing the carrier from sintering during the high-temperature catalytic reaction, resulting in aggregation and inactivation of the catalyst active components, and improving the catalyst's anti-carbon deposition performance. On the other hand, the auxiliary components or active components form a "shell" on the carrier surface to achieve high dispersion on the carrier surface to expose more active sites. At the same time, the close proximity between the active component and the auxiliary component enhances the electronic synergistic effect between the two, and effectively improves the catalyst carbon deposition problem during the methane reforming process. The multi-layer core-shell structure nickel-based catalyst of the present invention has a stable core-shell structure, excellent catalytic activity and anti-carbon deposition performance, and has important economic value and promotion significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0028] Figure 1 It is a schematic diagram of the structure of the multi-layer core-shell catalyst of the present application.

[0029] Figure 2 1 is a graph showing the change in methane conversion rate over time at 800° C. for Example 1 and Comparative Example 1 of the present application.

[0030] Figure 3 The graph of the methane conversion rate of Example 3 and Comparative Example 3 at 800°C over time is shown in FIG. DETAILED DESCRIPTION

[0031] In order to better illustrate the purpose, technical scheme and advantages of the present invention, the present invention is further described by the following examples. Obviously, the following examples are only part of the embodiments of the present invention, rather than all the embodiments; it should be understood that the embodiments of the present invention are only used to illustrate the technical effects of the present invention, rather than to limit the scope of protection of the present invention.

[0032] The raw materials in the examples can all be obtained commercially; unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0033] Example 1

[0034] A method for preparing a multilayer core-shell structured nickel-based catalyst comprises the following steps:

[0035] S1. According to the target catalyst composition: 80wt.% alumina carrier, 5wt.% oxygen conductive component cerium oxide, 5wt.% calcium oxide, 10wt.% active component nickel, calculate and weigh the mass of each component;

[0036] S2. Aluminum nitrate was dissolved in an ethanol solution and stirred until completely dissolved to obtain a solution concentration of 2 mol / L of a carrier solution, and a 1:1 volume of ethylenediamine alcohol solution was added dropwise to adjust the pH value to 5.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a precursor suspension for standby use;

[0037] S3. The cerium nitrate and ethanol were fully mixed to obtain a 0.5 mol / L oxygen-conducting rare earth additive solution, and the volume of 1: 1 ethylenediamine alcohol solution was simultaneously added dropwise to the precursor suspension obtained in S2, the pH value was adjusted to 6, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a single-layer core-shell catalyst precursor suspension;

[0038] S4. Calcium nitrate and ethanol were fully mixed to obtain a 0.5 mol / L carbon dioxide adsorption aid solution, which was added dropwise to the precursor suspension obtained in S3 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value was adjusted to 6.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a double-layer core-shell structure catalyst precursor suspension;

[0039] S5. nickel nitrate and ethanol are fully mixed to obtain a 1 mol / L nickel solution, and the solution is added dropwise to the precursor suspension obtained in S4 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value is adjusted to 9.5 until complete precipitation, stirring and ultrasonicating for 2 hours, standing for 16 hours, and centrifuging and filtering the precipitate to obtain a multilayer core-shell structure catalyst precursor;

[0040] S6. The multilayer core-shell structure catalyst precursor obtained in S5 is calcined at 700°C for 4 hours and reduced at 750°C for 3 hours under H2 atmosphere to obtain the multilayer core-shell structure nickel-based catalyst.

[0041] Example 2

[0042] A method for preparing a multilayer core-shell structured nickel-based catalyst comprises the following steps:

[0043] S1. According to the target catalyst composition: 90wt.% of zirconium oxide carrier, 0.5wt.% of oxygen-conducting auxiliary component lanthanum oxide, 4.5wt.% of magnesium oxide, 5wt.% of active component nickel, calculate and weigh the mass of each component;

[0044] S2. The zirconium oxychloride was dissolved in an ethanol solution and stirred until completely dissolved to obtain a solution concentration of 2 mol / L of the carrier solution, and a 1:1 volume of ethylenediamine alcohol solution was added dropwise to adjust the pH value to 5.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a precursor suspension for standby use;

[0045] S3. The lanthanum nitrate and ethanol were fully mixed to obtain a 0.5 mol / L oxygen-conducting rare earth additive solution, which was added dropwise to the precursor suspension obtained in S2 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value was adjusted to 6. The mixture was stirred and ultrasonicated for 2 hours and allowed to stand for 4 hours to obtain a single-layer core-shell catalyst precursor suspension;

[0046] S4. Magnesium nitrate and ethanol were fully mixed to obtain a 0.5 mol / L carbon dioxide adsorption aid solution, which was added dropwise to the precursor suspension obtained in S3 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value was adjusted to 6.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a double-layer core-shell catalyst precursor suspension;

[0047] S5. nickel nitrate and ethanol are fully mixed to obtain a 1 mol / L nickel solution, and the solution is added dropwise to the precursor suspension obtained in S4 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value is adjusted to 9.5 until complete precipitation, stirring and ultrasonicating for 2 hours, standing for 16 hours, and centrifuging and filtering the precipitate to obtain a multilayer core-shell structure catalyst precursor;

[0048] S6. The multilayer core-shell structure catalyst precursor obtained in S5 is calcined at 700°C for 4 hours and reduced at 750°C for 3 hours under H2 atmosphere to obtain the multilayer core-shell structure nickel-based catalyst.

[0049] Example 3

[0050] A method for preparing a multilayer core-shell structured nickel-based catalyst comprises the following steps:

[0051] S1. According to the target catalyst composition: alumina carrier 70wt.%, oxygen-conducting auxiliary component lanthanum oxide 4.5wt.%, calcium oxide 0.5wt.%, active component nickel 25wt.%, calculate and weigh the mass of each component;

[0052] S2. Aluminum nitrate was dissolved in an ethanol solution and stirred until completely dissolved to obtain a solution concentration of 2 mol / L of a carrier solution, and a 1:1 volume of ethylenediamine alcohol solution was added dropwise to adjust the pH value to 4.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a precursor suspension for standby use;

[0053] S3. The lanthanum nitrate and ethanol were fully mixed to obtain a 0.5 mol / L oxygen-conducting rare earth additive solution, which was added dropwise to the precursor suspension obtained in S2 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value was adjusted to 6. The mixture was stirred and ultrasonicated for 2 hours and allowed to stand for 4 hours to obtain a single-layer core-shell catalyst precursor suspension;

[0054] S4. Calcium nitrate and ethanol were fully mixed to obtain a 0.5 mol / L carbon dioxide adsorption aid solution, which was added dropwise to the precursor suspension obtained in S3 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value was adjusted to 6.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a double-layer core-shell structure catalyst precursor suspension;

[0055] S5. nickel nitrate and ethanol are fully mixed to obtain a 1 mol / L nickel solution, and the solution is added dropwise to the precursor suspension obtained in S4 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value is adjusted to 9.5 until complete precipitation, stirring and ultrasonicating for 2 hours, standing for 16 hours, and centrifuging and filtering the precipitate to obtain a multilayer core-shell structure catalyst precursor;

[0056] S6. The multilayer core-shell structure catalyst precursor obtained in S5 is calcined at 700°C for 4 hours and reduced at 750°C for 3 hours under H2 atmosphere to obtain the multilayer core-shell structure nickel-based catalyst.

[0057] Comparative Example 1

[0058] A method for preparing a nickel-based catalyst comprises the following steps:

[0059] S1. According to the target catalyst composition: 90wt.% alumina carrier, 10wt.% active component nickel, calculate and weigh the mass of each component;

[0060] S2. First, aluminum nitrate was dissolved in an ethanol solution and stirred until completely dissolved to obtain a solution with a concentration of 2 mol / L, and then nickel nitrate was added to a solution of 0.1 mol / L, and a 1:1 volume ethylenediamine alcohol solution was added dropwise to adjust the pH value to 9.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 16 hours to obtain a precursor suspension, and the precipitate was centrifuged and filtered for standby use;

[0061] S3. The precursor obtained in S2 is calcined at 600°C for 4 hours and reduced at 700°C for 3 hours under H2 atmosphere to obtain the nickel-based catalyst.

[0062] Compared with Example 1, this comparative example lacks the auxiliary agent component, and the nickel is directly loaded on the carrier without forming a core-shell structure.

[0063] Comparative Example 2

[0064] A method for preparing a nickel-based catalyst comprises the following steps:

[0065] S1. According to the target catalyst composition: 90wt.% of zirconium oxide carrier, 0.5wt.% of oxygen-conducting auxiliary component lanthanum oxide, 4.5wt.% of magnesium oxide, 5wt.% of active component nickel, calculate and weigh the mass of each component;

[0066] S2. First, zirconium oxychloride was dissolved in an ethanol solution, stirred until completely dissolved, stirred until completely dissolved, and a solution concentration of 2 mol / L was obtained, and lanthanum nitrate, magnesium nitrate, and nickel nitrate were added to form 0.5 mol / L, 0.5 mol / L, and 0.1 mol / L solutions, and a 1:1 volume of ethylenediamine alcohol solution was added dropwise to adjust the pH value to 9.5, stirred, ultrasonicated for 2 hours, and allowed to stand for 16 hours to obtain a precursor suspension, and the precipitate was centrifuged and filtered for standby use;

[0067] S3. The precursor obtained in S2 is calcined at 650°C for 4 hours and reduced at 700°C for 3 hours under H2 atmosphere to obtain the nickel-based catalyst.

[0068] Compared with Example 2, the nickel in this comparative example is directly loaded onto the carrier without forming a core-shell structure.

[0069] Comparative Example 3

[0070] A method for preparing a nickel-based catalyst comprises the following steps:

[0071] S1. According to the target catalyst composition: alumina carrier 70wt.%, oxygen-conducting auxiliary component lanthanum oxide 4.5wt.%, calcium oxide 0.5wt.%, active component nickel 25wt.%, calculate and weigh the mass of each component;

[0072] S2. Aluminum nitrate was dissolved in an ethanol solution and stirred until completely dissolved to obtain a solution concentration of 2 mol / L of a carrier solution, and a 1:1 volume of ethylenediamine alcohol solution was added dropwise to adjust the pH value to 5.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a precursor suspension for standby use;

[0073] S3. Calcium nitrate, lanthanum nitrate and ethanol were fully mixed to obtain a 0.5 mol / L solution, which was added dropwise to the precursor suspension obtained in S2 at the same time as a 1:1 volume ethylenediamine alcohol solution, and the pH value was adjusted to 6.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 4 hours to obtain a single-layer core-shell catalyst precursor suspension;

[0074] S4. nickel nitrate and ethanol are fully mixed to obtain a 1 mol / L solution, and the solution is added dropwise to the precursor suspension obtained in S2 at the same time as a 1:1 volume ethylenediamine alcohol solution, the pH value is adjusted to 9.5, stirred and ultrasonicated for 2 hours, and allowed to stand for 16 hours to obtain a double-layer core-shell structure catalyst precursor suspension, and the precipitate is centrifuged to obtain a double-layer core-shell structure catalyst precursor;

[0075] S5. The precursor obtained in S4 is calcined at 600°C for 4 hours and reduced at 700°C for 3 hours under H2 atmosphere to obtain the double-layer core-shell nickel-based catalyst.

[0076] Compared with Example 3, this comparative example has a double-layer core-shell structure.

[0077] The above samples were subjected to performance tests, and the experimental test methods are as follows:

[0078] The catalyst obtained above was pressed into tablets at 10MPa, and after crushing, 20-40 mesh particles were taken for methane carbon dioxide reforming reaction performance test. The reaction was carried out in a fixed bed microreactor (reaction tube inner diameter 6mm), 0.1g of the multilayer core-shell structure nickel-based catalyst was weighed and loaded into the reaction tube, hydrogen was passed under normal pressure, and the temperature was programmed to 800℃ for reduction, and the hydrogen flow rate was 30mL / min; after the multilayer core-shell structure nickel-based catalyst was reduced, hydrogen was switched to raw gas (Ar / CH4 / CO2=4 / 48 / 48), the flow rate was 35mL / min, GHSV=21000mL·g -1 ·h -1 The reaction was carried out at 800° C. The reaction products were analyzed online by gas chromatography GC (SP-2100A)-thermal conductivity detector TCD.

[0079] The test results of Examples 1-3 and Comparative Examples 1-3 are shown in the following table:

[0080] Table 1 Test results of Examples 1-3 and Comparative Examples 1-3

[0081]

[0082]

[0083] As can be seen from Table 1, under the same reaction time, the methane conversion rate of Example 1 decreased by 7% compared with Comparative Example 1, which has similar components. However, since the nickel is directly loaded on the carrier to obtain a nickel-based catalyst, no core-shell structure is formed in Comparative Example 1, and the methane conversion rate decreased by 70%; under the long-term reaction conditions of 40 hours for Example 2 and Comparative Example 2, the initial catalytic activity of Example 2 is excellent, and the methane conversion rate of the long-term reaction only decreases by 10%, while Comparative Example 2 effectively prolongs the service life of the nickel-based catalyst by loading nickel and auxiliary components on the carrier together, but the 20% decrease in methane conversion rate shows a significant gap compared with Example 2; under the long-term reaction conditions of 60 hours for Example 3 and Comparative Example 3, which have similar components, the methane conversion rate of Example 3 with a multilayer core-shell structure initially has a high methane conversion rate of 98%, and the methane conversion rate only decreases by 9% after 60 hours of reaction, which has excellent catalytic activity and anti-carbon deposition performance, while Comparative Example 3 with a double-layer core-shell structure also has a high methane conversion rate of 93% initially, combined with the attached Figure 3 It can be seen that it still has a high methane conversion rate when reacted at a high temperature of 800°C for 40 hours, but then it drops rapidly. After 60 hours of reaction, the methane conversion rate drops by 38%, indicating that the double-layer core-shell structure has certain catalytic activity and anti-carbon deposition performance, but the multi-layer core-shell structure is more superior. When the multi-layer core-shell structure nickel-based catalyst of each embodiment of the present invention is used for DRM reaction, it still has an excellent methane conversion rate at 800°C for a long reaction, and has excellent catalytic activity and anti-carbon deposition performance.

[0084] In summary, the multi-layer core-shell structure nickel-based catalyst of the present invention has a carrier as a core, and auxiliary components and active components as a shell. During the reaction process, on the one hand, the shell layer can block carbon deposition during the reaction process, which can prevent the carrier from sintering during the high-temperature catalytic reaction, resulting in aggregation and inactivation of the catalyst active components, thereby improving the catalyst's anti-carbon deposition performance. On the other hand, the auxiliary components or active components form a "shell" on the carrier surface to achieve a high degree of dispersion on the carrier surface to expose more active sites; at the same time, the close proximity between the active component and the auxiliary component enhances the electronic synergistic effect between the two, effectively improving the catalyst carbon deposition problem during the methane reforming process; the multi-layer core-shell structure nickel-based catalyst of the present invention has a stable core-shell structure, excellent catalytic activity and anti-carbon deposition performance, and has important economic value and promotion significance.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing a multilayer core-shell structured nickel-based catalyst, characterized in that: The following steps are involved: S1. Calculate and weigh the mass of each component according to the target catalyst composition; S2. The carrier precursor and the solvent are fully mixed to obtain a carrier precursor solution, and an alkaline solution is added dropwise to adjust the pH value to the pH range of carrier ion precipitation, stirred, ultrasonicated, and allowed to stand for 4-12 hours to obtain a precursor suspension for standby use; S3. The oxygen-conducting rare earth additive precursor is fully mixed with the solvent to obtain an oxygen-conducting rare earth additive precursor solution, and the solution is added dropwise to the precursor suspension obtained in S2 at the same time as the alkaline solution, and the pH value is adjusted to the pH value range of the oxygen-conducting rare earth additive ion precipitation, stirred, ultrasonicated, and allowed to stand for 4-12 hours to obtain a single-layer core-shell catalyst precursor suspension; S4. The carbon dioxide adsorption aid precursor is fully mixed with the solvent to obtain a carbon dioxide adsorption aid precursor solution, and the alkaline solution is simultaneously added dropwise to the precursor suspension obtained in S3, and the pH value is adjusted to the pH value range of carbon dioxide adsorption aid ion precipitation, stirred, ultrasonicated, and allowed to stand for 4-12 hours to obtain a double-layer core-shell structure catalyst precursor suspension; S5. The nickel source and the solvent are fully mixed to obtain a nickel solution, which is added dropwise to the precursor suspension obtained in S4 together with the alkaline solution, the pH value is adjusted to the pH range for nickel ion precipitation, stirred, ultrasonicated, allowed to stand for 12-24 hours, and the precipitate is filtered to obtain a multilayer core-shell catalyst precursor; S6. The multilayer core-shell structure catalyst precursor obtained in S5 is calcined and reduced to obtain the multilayer core-shell structure nickel-based catalyst; S6: the calcination temperature is 600-800°C and the time is 4h; the reduction is carried out under H2 atmosphere at a temperature of 700-750°C and a time of 3-5h.

2. The method for preparing a multi-layer core-shell structured nickel-based catalyst according to claim 1, characterized in that: The target catalyst composition of S1 is: nickel 5-25 wt.%, carrier 70-90 wt.%, oxygen-conducting rare earth additive 0.5-5 wt.%, carbon dioxide adsorption additive 0.5-5 wt.%.

3. The method for preparing a multi-layer core-shell structured nickel-based catalyst according to claim 1, characterized in that: S2 The carrier precursor is one or more of aluminum nitrate, aluminum chloride, and zirconium oxychloride.

4. The method for preparing a multi-layer core-shell structured nickel-based catalyst according to claim 1, characterized in that: S3: The oxygen-conducting rare earth auxiliary agent precursor is cerium nitrate and / or lanthanum nitrate.

5. The method for preparing a multi-layer core-shell structured nickel-based catalyst according to claim 1, characterized in that: S4 The carbon dioxide adsorption aid precursor is one or more of calcium nitrate, calcium acetate, magnesium nitrate, magnesium acetate, potassium nitrate and potassium acetate.

6. The method for preparing a multi-layer core-shell structured nickel-based catalyst according to claim 1, characterized in that: The nickel source in S5 is nickel nitrate.

7. The method for preparing a multi-layer core-shell structured nickel-based catalyst according to claim 1, characterized in that: The solvents in S2, S3, S4 and S5 are independently deionized water or ethanol, and the alkaline solutions in S2, S3, S4 and S5 are independently one or more of ethylenediamine alcohol solution and ammonia aqueous solution.

8. The method for preparing a multi-layer core-shell structured nickel-based catalyst according to claim 1, characterized in that: The ultrasonic time in S2, S3, S4 and S5 is independently selected from 10-60 min.

9. A multilayer core-shell structured nickel-based catalyst, characterized in that: Prepared according to the preparation method according to any one of claims 1 to 8.

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