A barium carbonate supported nickel-based methanation catalyst, its preparation method and use

Abstract

This invention relates to a barium carbonate-supported nickel-based methanation catalyst, its preparation method, and its application. The catalyst comprises 90% barium carbonate support and 10% nickel by mass. The catalyst provided by this invention is based on BaCO3 prepared by precipitation, using a deposition-precipitation method to prepare 10wt% Ni / BaCO3. During pretreatment and reaction, a support coating layer forms on the nickel nanoparticles. This coating layer, through its own dissociation and regeneration, promotes CO2 adsorption, thereby increasing the methane formation rate. Simultaneously, the coating layer immobilizes the nickel particles, improving stability. Therefore, the catalyst prepared by this invention possesses numerous advantages, including structural stability, good thermal conductivity, high-efficiency CO2 conversion and CH4 selectivity, high permeability and high activity, high mechanical strength, ease of molding and filling, and high throughput with low pressure drop. It is an excellent catalyst for the carbon dioxide hydrogenation to methane reaction and is suitable for industrial applications.

Description

Technical Field

[0001] This invention relates to a methanation catalyst, and more particularly to a barium carbonate-supported nickel-based methanation catalyst and its preparation method. Background Technology

[0002] Improving the efficiency and methods of traditional energy utilization will be a top priority in the global energy transition. Carbon dioxide methanation is emerging as an interesting strategy, offering advantages such as low investment, high thermal efficiency, and low cost. It also aligns well with the green hydrogen route, enabling the on-site conversion of low-calorific-value lignite, high-sulfur coal, or coal with high transportation costs in remote areas into natural gas for utilization, and thus has significant future development potential.

[0003] Considering industrial-scale conversion, a nickel (Ni) catalyst with high reactivity and low cost is selected. Supported nickel-based catalysts exhibit strong structure sensitivity in the CO2 methanation reaction, and the choice of support significantly influences the catalyst's structure and performance. Extensive research has selected metal or non-metal oxides (such as CeO2, Al2O3, Y2O3, ZrO2, TiO2, SiO2, HAP, BN, and TiB2) with basic sites and high mechanical and thermal stability as supports for Ni-based catalysts. Through controlling the preparation methods, such as altering reaction conditions (temperature, equilibrium gas, and Ni loading), modifying the methods for treating Ni-based catalysts (traditional methods, DBD plasma, strong electrostatic adsorption encapsulation of Ni nanoparticles), and controlling Ni loading positions by doping with metal ions or solvents to increase oxygen vacancies, the catalysts exhibit good performance and resistance to coking and sintering. Currently, the applicant believes there is an urgent need to discover a novel approach to prepare support materials, utilizing the support to provide CO3. 2- This promotes the rapid cycling of the CO2 methanation pathway, producing CO3. 2- The carrier material also exhibited good performance. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art by providing a barium carbonate-supported nickel-based methanation catalyst, its preparation method, and its application. It provides a method for preparing a barium carbonate-supported nickel-based catalyst with excellent activity, high methane selectivity, good stability, and easy molding and packing, and its application in the carbon dioxide hydrogenation to methane reaction.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] This invention provides a barium carbonate-supported nickel-based methanation catalyst, wherein the methanation catalyst comprises a barium carbonate support and a nickel-based material supported thereon, wherein the total mass of the barium carbonate support accounts for 90%, and the remainder is the active component nickel, accounting for 10%, with the content based on the total mass of the catalyst.

[0007] The methanation catalyst is prepared by the following method: first, a barium carbonate support is prepared by precipitation, and then a NiO / BaCO3 catalyst is prepared by precipitation-impregnation method, thus obtaining the barium carbonate supported nickel-based methanation catalyst.

[0008] Furthermore, the methanation catalyst can form a barium carbonate support coating layer on the nickel nanoparticles during pretreatment and reaction. This coating layer promotes CO2 adsorption through its own dissociation and regeneration, thereby increasing the methane generation rate.

[0009] Furthermore, the coating layer can fix the nickel particles and improve the stability of the material structure.

[0010] A second aspect of the present invention provides a method for preparing a barium carbonate-supported nickel-based methanation catalyst as described above, comprising the following steps:

[0011] A solution A is obtained by dissolving a metal salt of barium in an aqueous alcohol solution.

[0012] Under mechanical stirring, the carbonate was dissolved in an aqueous alcohol solution and added dropwise to solution A. After mixing thoroughly, mixture B was obtained.

[0013] Mixture B was centrifuged, washed, and dried to obtain solid C;

[0014] Solid C is ground into powder and calcined at 400-500℃ for 2-5 h to obtain solid D;

[0015] Dissolve a nickel metal salt in an appropriate amount of water to obtain solution E;

[0016] Under ultrasonic conditions, solid D is added to water to obtain mixture F;

[0017] Solution E is added to mixture F in the ultrasonic process to obtain mixture G;

[0018] Under mechanical stirring, the carbonate was dissolved in an aqueous solution and added dropwise to mixture G. After mixing evenly, mixture H was obtained.

[0019] The mixture H was continuously stirred, centrifuged and washed multiple times, and then dried in an oven to obtain solid I;

[0020] S10: Grind solid I into powder and calcine it at 400~500℃ for 2~5 h to obtain the catalyst.

[0021] Furthermore, it includes the following steps:

[0022] S1: Under mechanical stirring, add BaCl2 with a concentration of 0.05~0.20 mol / L. Add the 2H₂O aqueous alcohol solution dropwise to the (NH₄)₂CO₃ aqueous alcohol solution with a concentration of 0.14~0.30 mol / L, according to Ba... 2+ With CO3 2- The components are mixed in a molar ratio of 1.5:1 to 1:2 and stirred to obtain mixture A;

[0023] S2: Centrifuge, wash, dry, and grind mixture A to obtain solid B;

[0024] S3: The solid B is placed in an inert atmosphere and heated to a calcination temperature of 400-500℃ at a heating rate of 2℃ / min to 10℃ / min for 2-5 hours, and then cooled to room temperature to obtain solid D.

[0025] S4: Disperse the solid D in deionized water using ultrasonication to form mixture E;

[0026] S5: Add an aqueous solution of Ni(NO3)2·6H2O with a concentration of 0.03 mol / L to mixture E under ultrasonic conditions to obtain a new mixture F;

[0027] S6: Under mechanical stirring, add dropwise a 0.05~0.10 mol / L (NH4)2CO3 aqueous solution to mixture F according to Ni. 2+ With CO3 2- The mixtures were mixed in a molar ratio of 1:1 to 1:2 and stirred to obtain mixture G;

[0028] S7: Centrifuge, wash, dry, and grind the mixture G to obtain solid H;

[0029] S8: The solid H is placed in an air atmosphere and calcined at a calcination temperature of 400-500℃ for 2-5 hours with a heating rate of 2℃ / min to 10℃ / min. After cooling to room temperature, a 10wt% NiO / BaCO3 catalyst is obtained.

[0030] Furthermore, the volume fraction ratio of water to ethanol in the aqueous alcohol solution is 1:1 to 4:1;

[0031] The mechanical stirring speed is 700-1000 rpm.

[0032] Furthermore, the dropping rate of the (NH4)2CO3 aqueous alcohol solution is 0.5~2 mL / min;

[0033] The number of centrifugation and washing cycles is 5 to 10.

[0034] The drying conditions are non-vacuum 60~120℃, and the drying time is 6~12h.

[0035] A third aspect of the present invention provides an application of the barium carbonate-supported nickel-based methanation catalyst as described above, wherein the catalyst is first pretreated, and then reacted at a reaction temperature of 150-500°C, a reaction pressure of atmospheric pressure, and a space velocity of 60,000 L / (kg⁻¹). cat Under the conditions of ·h), a nickel-based catalyst supported on barium carbonate is reacted with a reaction gas to produce methane.

[0036] Furthermore, the pretreatment process of the methanation catalyst:

[0037] S1: Place the prepared catalyst in a tubular reactor;

[0038] S2: Open the gas valve, introduce inert gas, and maintain a space velocity of 120,000 L / (kg). cat (·h), heat to 400~600°C;

[0039] S3: Switch to pre-treated gas, maintain air velocity at 120,000 L / (kg) cat · h), keep stable at 400~600°C for 0.5~2h.

[0040] Furthermore, the pretreatment gas is a mixture of hydrogen and an inert gas;

[0041] The reactant gas is a mixture of hydrogen, carbon dioxide, and an inert gas.

[0042] Furthermore, the pretreatment gas was 10% H2 + 90% N2, the gas flow rate was 50 mL / min, and it was kept stable at 500°C for 1 hour.

[0043] Furthermore, the feed gas is 15% CO2 + 60% H2 + 25% N2, and the gas flow rate is 25 mL / min.

[0044] Compared with the prior art, the present invention has the following technical advantages:

[0045] 1) The carbonate-supported nickel-based catalyst prepared by the method of this invention can form a support coating layer on nickel nanoparticles during pretreatment and reaction. This coating layer, through its own dissociation and regeneration, promotes CO2 adsorption, thereby increasing the methane production rate. Simultaneously, the coating layer structure anchors the nickel particles, improving structural stability. This achieves efficient and stable catalytic reaction, simultaneously meeting the requirements of rapid heat / mass transfer and good catalytic performance in strongly exothermic reactions in chemical processes, making it an excellent catalyst for the hydrogenation of carbon dioxide to methane.

[0046] 2) The preparation process of this invention is economical and practical, the preparation process is simple, the raw materials are readily available and inexpensive, the structure is controllable, no special equipment or harsh conditions are required, and it is easy to achieve large-scale production, thus possessing extremely high practical value. Attached Figure Description

[0047] Figure 1 The image shows the XRD pattern of the nickel-based catalyst sample supported on barium carbonate in this invention.

[0048] Figure 2 This is a scanning electron microscope (SEM) image of a nickel-based catalyst sample supported on barium carbonate and strontium carbonate in this invention.

[0049] Figure 3 This is a Raman spectroscopy image of the nickel-based catalyst sample supported on barium carbonate in this invention;

[0050] Figure 4 The graph shows the activity data of the barium carbonate-supported nickel-based catalyst and other carbonate-supported nickel-based catalysts in this invention (at different reaction temperatures).

[0051] Figure 5 Stability graphs (300°C) of the barium carbonate-supported nickel-based catalyst and other carbonate-supported nickel-based catalysts in this invention. Detailed Implementation

[0052] Overall, this invention provides a method for preparing a barium carbonate-supported nickel-based methanation catalyst. The barium carbonate-supported nickel-based methanation catalyst consists of a barium carbonate support and nickel supported thereon, with the barium carbonate support comprising 90% by mass and the nickel comprising 10%. The catalyst provided by this invention is based on BaCO3 prepared by precipitation, using a deposition-precipitation method to prepare 10wt% Ni / BaCO3. During pretreatment and reaction, the obtained 10wt% Ni / BaCO3 catalyst can form a support coating layer on the nickel nanoparticles. This coating layer, through its own dissociation and regeneration, promotes CO2 adsorption, thereby increasing the methane formation rate; simultaneously, the coating layer can immobilize the nickel particles, improving stability. Therefore, the catalyst prepared by this invention has many advantages, including structural stability, good thermal conductivity, high CO2 conversion (87.27%) and CH4 selectivity (98.41%), high permeability and high activity, high mechanical strength, ease of molding, ease of filling, and high throughput with low pressure drop. It is an excellent catalyst for the carbon dioxide hydrogenation to methane reaction and is suitable for industrial applications.

[0053] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Any preparation methods, materials, structures, or compositional ratios not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0054] Example 1

[0055] This embodiment describes a barium carbonate-supported nickel-based methanation catalyst, which consists of an active component Ni and a BaCO3 support. The mass ratio of the catalyst NiO: BaCO3 is 1:9 (or the loading of the active component Ni on the BaCO3 support is 10 wt.%), and the contents are based on the total mass of the catalyst.

[0056] The preparation process of 10wt% Ni / BaCO3 in this embodiment is as follows:

[0057] S1: Dissolve 1.24 g BaCl2·2H2O in 70 ml of aqueous alcohol solution (50 mL deionized water + 25 mL ethanol);

[0058] S2: Dissolve 1.0 g (NH4)2CO3 in 70 ml of aqueous alcohol solution (50 mL deionized water + 25 mL ethanol), and add it dropwise to the solution obtained in step S1 at a dropping rate of 1 mL / min. Stir continuously at 800 rpm during the dropping process.

[0059] S3: Centrifuge, wash, and dry the above mixture;

[0060] S4: Grind the above solid into powder and calcine it at 450°C for 3 hours to obtain BaCO3 powder;

[0061] S5: Mix the obtained 0.90 g BaCO3 powder with 50 mL of deionized water under ultrasonication;

[0062] S6: Dissolve 0.39 g Ni(NO3)2·6H2O in 50 mL of deionized water and add it to the barium carbonate-water mixture in the ultrasonication.

[0063] S7: Dissolve 0.26 g (NH4)2CO3 in 50 ml of aqueous solution, add it to the barium carbonate-water mixture obtained in step S6, drop at a rate of 1 mL / min, and stir continuously at 800 rpm during the drop process;

[0064] S8: After continuously stirring the mixture and centrifuging and washing it multiple times, place it in an oven at 60℃ and dry for 12 hours;

[0065] S9: Grind the above solid into powder and calcine at 450°C for 3 hours to obtain the catalyst.

[0066] Verification Example 1

[0067] Catalyst pretreatment process:

[0068] S1: Place 25 mg of the prepared catalyst into a tubular reactor.

[0069] S2: Open the gas valve, introduce Ar at a gas flow rate of 50 mL / min, and heat to 500°C at a rate of 10°C / min for 50 min.

[0070] S3: Switch to pretreatment gas (10% H2 + 90% N2), gas flow rate is 50 mL / min, maintain stable at 500°C for 1 hour.

[0071] Catalyst evaluation is divided into catalyst activity evaluation and stability evaluation. The steps for catalyst activity evaluation are as follows:

[0072] S1: Switch to feed gas (15%CO2+60%H2+25%N2), gas flow rate is 25mL / min.

[0073] S2: Adjust the reaction temperature and analyze the composition of the gaseous products every 20 minutes under steady-state conditions. Several temperature control points were set up: 250, 300, 350, and 400 °C. Tests were conducted from low to high temperatures, with each temperature held for 120 minutes. The reaction results are shown in Table 1 and... Figure 4 , 5 .

[0074] The steps for evaluating the stability of a catalyst are as follows:

[0075] S1: Place 25 mg of the prepared catalyst into a tubular reactor.

[0076] S2: Open the gas valve, introduce Ar at a gas flow rate of 50 mL / min, and heat to 500°C at a rate of 10°C / min for 50 min.

[0077] S3: Switch to pretreatment gas (10% H2 + 90% N2), gas flow rate is 50 mL / min, maintain stable at 500°C for 1 hour.

[0078] S4: Switch to feed gas (15%CO2+60%H2+25%N2), gas flow rate is 25mL / min, maintain stable at 300°C for 100h, the reaction results are shown in Table 1 and Figure 2.

[0079] The barium carbonate-supported nickel catalyst, after reduction activation and a 120-minute reaction, yielded XRD, TEM, and Raman characterization results, as shown in Figures 1, 2, and 3. XRD showed no characteristic Ni peaks, indicating high Ni dispersion. TEM revealed the formation of a coating layer, suggesting that pretreatment and the reaction process altered the relative positions of the nickel atoms and the barium carbonate support on the catalyst surface. This coating layer, through hydrogen dissociation and regeneration, promotes CO2 adsorption, increases formate concentration at the interface, and facilitates the self-circulation of the Ba support during the reaction. Simultaneously, the coating layer immobilizes Ni particles, improving stability. The Raman characterization also shows CO3... 2- The changes in proportions during the untreated, pretreated, and reaction processes demonstrate how reduction promotes the hydrogenation and dissociation of BaCO3, and CO3. 2- The concentration decreases; during the reaction, CO2 in the atmosphere can be regenerated from BaCO3, and CO3... 2- An in-situ process that increases concentration.

[0080] Comparative Example 1

[0081] A strontium carbonate-supported nickel-based methanation catalyst is disclosed. The catalyst consists of an active component (Ni) and a support (SrCO3) with a mass ratio of NiO:SrCO3 = 1:9. All contents are based on the total mass of the catalyst. The preparation process of 10wt% Ni / SrCO3 in this embodiment is as follows.

[0082] S1: Dissolve 1.80 g SrCl2·6H2O in 70 ml of aqueous alcohol solution (50 mL deionized water + 25 mL ethanol);

[0083] S2: Dissolve 1.3 g (NH4)2CO3 in 70 ml of aqueous alcohol solution (50 mL deionized water + 25 mL ethanol), add it to the solution obtained in step S1, and add it at a dropping rate of 1 mL / min while stirring continuously at 800 rpm during the dropping process.

[0084] S3: Centrifuge, wash, and dry the above mixture;

[0085] S4: Grind the above solid into powder and calcine it at 450°C for 3 hours to obtain SrCO3 powder;

[0086] S5: Mix the obtained 0.90 g SrCO3 powder with 50 mL of deionized water under ultrasonication;

[0087] S6: Dissolve 0.39 g Ni(NO3)2·6H2O in 50 mL of deionized water and add the strontium carbonate-water mixture from the ultrasonication process;

[0088] S7: Dissolve 0.26 g (NH4)2CO3 in 50 ml of aqueous solution and add it to the strontium carbonate-water mixture obtained in step S6. The dropping rate is 1 mL / min, and the mixture is stirred continuously at 800 rpm during the dropping process.

[0089] S8: After continuously stirring the mixture and centrifuging and washing it multiple times, place it in an oven at 60℃ and dry for 12 hours;

[0090] S9: Grind the above solid into powder and calcine at 450°C for 3 hours to obtain the catalyst.

[0091] The catalyst pretreatment and evaluation processes used in this comparative example are the same as in Example 1; the specific steps are detailed in Example 1. The reaction results are shown in Table 1 and... Figure 4 , 5 .

[0092] Table 1: Catalyst performance in the examples and comparative examples under various catalyst evaluation conditions.

[0093]

[0094] The results show that, compared with traditional supported nickel catalysts, the barium carbonate-supported nickel catalyst, prepared by first using a precipitation method and then by a precipitation-impregnation method, exhibits significantly enhanced catalytic activity in the carbon dioxide methanation reaction after pretreatment. This is due to the formation of a porous interface on the support surface, which participates in the production and reaction of methane intermediates. While maintaining high stability, both the carbon dioxide conversion rate and methane yield are improved.

[0095] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A barium carbonate-supported nickel-based methanation catalyst, characterized in that, The methanation catalyst includes a barium carbonate support and a nickel-based material supported thereon. The total mass of the barium carbonate support accounts for 90%, and the remainder is the active component nickel, accounting for 10%. The contents are based on the total mass of the catalyst. The methanation catalyst is prepared by the following method: first, a barium carbonate support is prepared by precipitation, and then a NiO / BaCO3 catalyst is prepared by deposition precipitation method, thus obtaining the barium carbonate supported nickel-based methanation catalyst. During the pretreatment and reaction process, the methanation catalyst can form a barium carbonate support coating layer on the nickel nanoparticles. The coating layer promotes CO2 adsorption through its own dissociation and regeneration, thereby increasing the methane generation rate. The preparation method of the barium carbonate-supported nickel-based methanation catalyst includes the following steps: A solution A is obtained by dissolving a metal salt of barium in an aqueous alcohol solution. Under mechanical stirring, the carbonate was dissolved in an aqueous alcohol solution and added dropwise to solution A. After mixing thoroughly, mixture B was obtained. Mixture B was centrifuged, washed, and dried to obtain solid C; Solid C is ground into powder and calcined at 400-500℃ for 2-5 h to obtain solid D; Dissolve a nickel metal salt in an appropriate amount of water to obtain solution E; Under ultrasonic conditions, solid D is added to water to obtain mixture F; Solution E is added to mixture F in the ultrasonic process to obtain mixture G; Under mechanical stirring, the carbonate was dissolved in an aqueous solution and added dropwise to mixture G. After mixing evenly, mixture H was obtained. The mixture H was continuously stirred, centrifuged and washed multiple times, and then dried in an oven to obtain solid I; S10: Grind solid I into powder and calcine it at 400~500℃ for 2~5 h to obtain the catalyst.

2. A method for preparing a barium carbonate-supported nickel-based methanation catalyst as described in claim 1, characterized in that, Includes the following steps: A solution A is obtained by dissolving a metal salt of barium in an aqueous alcohol solution. Under mechanical stirring, the carbonate was dissolved in an aqueous alcohol solution and added dropwise to solution A. After mixing thoroughly, mixture B was obtained. Mixture B was centrifuged, washed, and dried to obtain solid C; Solid C is ground into powder and calcined at 400-500℃ for 2-5 h to obtain solid D; Dissolve a nickel metal salt in an appropriate amount of water to obtain solution E; Under ultrasonic conditions, solid D is added to water to obtain mixture F; Solution E is added to mixture F in the ultrasonic process to obtain mixture G; Under mechanical stirring, the carbonate was dissolved in an aqueous solution and added dropwise to mixture G. After mixing evenly, mixture H was obtained. The mixture H was continuously stirred, centrifuged and washed multiple times, and then dried in an oven to obtain solid I; S10: Grind solid I into powder and calcine it at 400~500℃ for 2~5 h to obtain the catalyst.

3. The method for preparing a barium carbonate-supported nickel-based methanation catalyst according to claim 2, characterized in that, Includes the following steps: S1: Under mechanical stirring, add dropwise a 0.14-0.30 mol / L (NH4)2CO3 aqueous alcohol solution to a 0.05-0.20 mol / L BaCl2·2H2O aqueous alcohol solution, according to Ba... 2+ With CO3 2- The components are mixed in a molar ratio of 1.5:1 to 1:2 and stirred to obtain mixture A; S2: Centrifuge, wash, dry, and grind mixture A to obtain solid B; S3: The solid B is placed in an inert atmosphere and heated to a calcination temperature of 400-500℃ at a heating rate of 2℃ / min to 10℃ / min for 2-5 hours, and then cooled to room temperature to obtain solid D. S4: Disperse the solid D in deionized water using ultrasonication to form mixture E; S5: Add an aqueous solution of Ni(NO3)2·6H2O with a concentration of 0.03 mol / L to mixture E under ultrasonic conditions to obtain a new mixture F; S6: Under mechanical stirring, add dropwise a 0.05~0.10 mol / L (NH4)2CO3 aqueous solution to mixture F according to Ni. 2+ With CO3 2- The mixtures were mixed in a molar ratio of 1:1 to 1:2 and stirred to obtain mixture G; S7: Centrifuge, wash, dry, and grind the mixture G to obtain solid H; S8: The solid H is placed in an air atmosphere and calcined at a calcination temperature of 400-500℃ for 2-5 hours with a heating rate of 2℃ / min to 10℃ / min. After cooling to room temperature, a 10wt% NiO / BaCO3 catalyst is obtained.

4. The method for preparing a barium carbonate-supported nickel-based methanation catalyst according to claim 3, characterized in that, The volume fraction ratio of water to ethanol in the aqueous alcohol solution is 1:1 to 4:

1. The mechanical stirring speed is 700-1000 rpm.

5. The method for preparing a barium carbonate-supported nickel-based methanation catalyst according to claim 3, characterized in that, The dropping rate of the (NH4)2CO3 aqueous alcohol solution is 0.5~2 mL / min; The number of centrifugation and washing cycles is 5 to 10. The drying conditions are non-vacuum 60~120℃, and the drying time is 6~12h.

6. The application of the barium carbonate-supported nickel-based methanation catalyst as described in claim 1, characterized in that, The catalyst is first pretreated, and then the reaction is carried out at a temperature of 150-500℃, a reaction pressure of atmospheric pressure, and a space velocity of 60,000 L / (kg⁻¹). cat Under the conditions of ·h), a nickel-based catalyst supported on barium carbonate is reacted with a reaction gas to produce methane; The reactant gas is a mixture of hydrogen, carbon dioxide, and an inert gas.

7. The application of the barium carbonate-supported nickel-based methanation catalyst according to claim 6, characterized in that, The pretreatment process of the methanation catalyst: S1: Place the prepared catalyst in a tubular reactor; S2: Open the gas valve, introduce inert gas, and maintain a space velocity of 120,000 L / (kg). cat (·h), heat to 400~600°C; S3: Switch to pre-treated gas, maintain air velocity at 120,000 L / (kg) cat · h), keep stable at 400~600°C for 0.5~2h.

8. The application of the barium carbonate-supported nickel-based methanation catalyst according to claim 6, characterized in that, The pretreatment gas is a mixture of hydrogen and inert gas.

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