Methanation catalyst and preparation method thereof

Abstract

The invention relates to the technical field of catalysts, in particular to a methanation catalyst and a preparation method thereof.The methanation catalyst comprises a carrier, an active component, a binder and a pore forming agent; the carrier comprises one or more of ZrO2 and YSZ (Yttria Stabilized Zirconia); the active component comprises one or more of NiO and CuO; the catalyst is of a tubular structure. The catalyst with the tubular structure can realize methanation of CO and / or CO2 under normal pressure, has the capability of rapidly amplifying production, and is convenient for production and application; the catalyst is high in carbon monoxide / carbon dioxide conversion rate, high in methane yield and continuous and stable in gas output; the combination degree between the active component and the carrier of the catalyst is high, the structure-activity relationship is good, and the catalyst has high stability and long service life; the catalyst is excellent in high temperature resistance and water resistance; in addition, the catalyst disclosed by the invention is simple in preparation process, good in reproducibility, low in cost and beneficial to industrial large-scale popularization and application.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a methanation catalyst and a preparation method thereof. Background Art

[0002] Natural gas is a non-renewable energy source, and the development of clean technologies to produce substitute natural gas (SNG) is crucial. Methane is an energy carrier and the main component of natural gas, which is of great significance to the global industrial and transportation sectors. Methanation technology has a history of more than 100 years and is widely used. It is one of the core components of the process of replacing raw materials such as coal, coke oven gas and electricity.

[0003] Many foreign research institutions and scholars have conducted extensive research on methanation technology, which has a history of a hundred years. For example, the British BG Gas Company uses naphtha as a raw material for conversion under low temperature conditions to produce low calorific value city gas. At present, this process has been well applied in many domestic coal-to-gas projects and has a good application prospect. Denmark's Topsoe uses synthesis gas with different gas components as raw materials to convert it into natural gas under high temperature conditions. The produced natural gas has high quality and can fully meet the transportation requirements of natural gas pipelines. my country's coal-to-gas projects supported by Topsoe's methanation technology have achieved commercial operation. The above technologies mainly rely on fixed bed reactors and fluidized bed reactors, which occupy a large area, consume a lot of energy, and require strict control of the reactor temperature.

[0004] Among the many methanogenic technologies, power-to-gas (P2G) technology is an effective way to solve the volatility and randomness of renewable energy generation, and is also an effective way to consume renewable electricity, with good development prospects. The main principle of power-to-methane technology is to convert synthesis gas into methane and water vapor through electrocatalysis. The main reactions are shown in equations (1) and (2).

[0005] Co+3H 2 =CH 4 +H 2 O ΔH=-206 kJ mol -1 (1)

[0006] CO 2 +4H 2 =CH 4 +2H 2 O ΔH=-165kJ mol -1 (2)

[0007] The advantage of power-to-gas technology is that it can convert electricity generated by renewable energy sources such as wind and solar energy into natural gas. Compared with other energy storage systems, this technology can provide more economic profits. However, due to technical limitations, the operation and optimization of power-to-gas still need more extensive research.

[0008] Precious metal catalysts have high low-temperature catalytic activity for methanation reactions, but they are expensive and not conducive to large-scale industrial production. Therefore, among the many Group VIII metal catalysts, nickel-based catalysts are widely used in methanation reactions due to their excellent catalytic performance and relatively low cost. The nickel-based tubular methanation reactor is a new type of methanation reactor that can efficiently convert crude synthesis gas into methane with a selectivity of almost 100%. The reactor structure is a metal ceramic with a low preparation cost and a longer operating life. In addition, the energy consumption of the reactor can be reduced by electrothermal coupling.

[0009] For syngas methanation technology, from the perspective of activity, Ru>Fe>Ni>Co; from the perspective of selectivity, Ni>Co>Fe>Ru. Although Ru helps the reaction occur at a faster rate, its application cost is too high. Given the high activity and selectivity of nickel and its low cost, nickel is considered a very favorable choice for promoting commercial methanation processes. In reactor selection, fixed bed reactors and fluidized bed reactor systems are considered common choices for synthetic natural gas production because these two reactor designs are simple and efficient. Honeycomb reactors and microchannel reactors are also used because these two structures are more conducive to exposing catalytic sites. However, the above reactors have defects in actual operation: fluidized bed reactors need to be under high pressure to operate effectively, which is complicated to operate; the outlet temperature of honeycomb reactors is difficult to control, resulting in a decrease in fuel conversion rate; the catalyst is not fully exposed in the fixed bed reactor structure, and the contact area between the catalyst and the syngas is limited. Therefore, it is necessary to study new alternative reactor technologies.

[0010] In view of this, the present invention is proposed. Summary of the invention

[0011] The object of the present invention is to provide a methanation catalyst and a preparation method thereof. The catalyst has high stability, high carbon monoxide / carbon dioxide conversion rate, high methane yield, simple preparation process, low cost, and is conducive to large-scale industrial promotion and use.

[0012] In a first aspect of the present invention, a methanation catalyst is provided, comprising: a carrier, an active component, a binder and a pore-forming agent; the carrier comprises: ZrO 2 , or one or more of YSZ; the active components include one or more of NiO and CuO; the catalyst is a tubular structure.

[0013] Preferably, the mass ratio of the carrier, active component, binder and pore-forming agent is 100:(5-7):(8-10), more preferably 100:6:9.

[0014] Preferably, the inner diameter of the catalyst is 2-4 mm, more preferably 3 mm.

[0015] Preferably, the carrier is 3YSZ (3 mol% Y 2 O 3 Stable ZrO 2 ), the active component is NiO, NiO and ZrO 2 The mass ratio of is 1:1; the binder is cellulose; and the pore-forming agent is starch.

[0016] A second aspect of the present invention provides a method for preparing a methanation catalyst, comprising the following steps:

[0017] S1, mixing the carrier, active component, binder, pore-forming agent and water into a muddy raw material and aging it for a period of time;

[0018] S2, casting the raw material of step S1 into a green billet of tubular structure by extrusion molding;

[0019] S3. The green body is calcined at high temperature and kept warm for a period of time and then cooled to room temperature to obtain a methanation catalyst.

[0020] Preferably, in step S1, the aging conditions include: under sealed storage, in a constant temperature and humidity environment, the aging time is 20-40 hours.

[0021] Preferably, the mass ratio of the carrier, active component, binder and pore-forming agent is 100:(5-7):(8-10), more preferably 100:6:9.

[0022] Preferably, the carrier is 3YSZ (3 mol% Y 2 O 3 Stable ZrO 2 ), the active component is NiO, NiO and ZrO 2 The mass ratio of is 1:1; the binder is cellulose; and the pore-forming agent is starch.

[0023] Preferably, in step S2, the raw material of step S1 is cast into a green body of a tubular structure by extrusion molding under vacuum conditions, and then dried for 18-24 hours.

[0024] Preferably, in step S3, the high temperature calcination temperature is 1000-1200° C., and the insulation time is 5-8 hours.

[0025] In a third aspect of the present invention, a methanation catalyst is provided for use in CO and / or CO 2 of methanogenation.

[0026] In a fourth aspect of the present invention, a methanation reactor is provided, which uses the above-mentioned methanation catalyst for CO and / or CO 2 of methanogenation.

[0027] Specifically, the catalyst of the present invention is used for CO and / or CO 2 In the methanogenesis process, the methanogenesis of CO is carried out through the following reaction equation:

[0028] CO+3H 2 →CH 4 +H 2 O

[0029] CO 2 The methanation of is carried out via the following reaction equation:

[0030] CO 2 +4H 2 →CH 4 +2H 2 O

[0031] Preferably, CO and / or CO 2 In the methanation process, the reaction temperature is controlled at 300-400°C, more preferably 350°C.

[0032] A fifth aspect of the present invention provides a method for preparing a methanation reactor, comprising the following steps:

[0033] P1, the catalysts are connected with each other through stainless steel fixtures, sealing materials and Fe-18Cr alloy, and dried in an oven to obtain an assembled reactor;

[0034] Preferably, the reactor is in the shape of an elongated strip;

[0035] P2, heating the reactor assembled in step P1 to 700-800°C to sinter and discharge the volatiles in the sealing material, and solidifying and forming the sealing material by external pressure;

[0036] P3, use SLM nitrogen and soap bubble flowmeter to measure the high temperature gas tightness of the reactor. When the leakage rate is less than 1%, it is used for CO and / or CO 2 of methanogenation.

[0037] The present invention has the following beneficial effects:

[0038] (1) The catalyst of the present invention has a tubular structure and can produce CO and / or CO at normal pressure. 2It has the ability to rapidly scale up production and is easy to use in production.

[0039] (2) The catalyst of the present invention can adjust the H / C ratio in the feed gas according to actual conditions to control the degree of carbon dioxide conversion, and has a high carbon monoxide / carbon dioxide conversion rate, a high methane yield, and a continuous and stable gas output.

[0040] (3) The active components of the catalyst of the present invention have a high degree of bonding with the carrier, a good structure-activity relationship, high stability, a long service life, and can operate continuously for more than a thousand hours.

[0041] (4) The catalyst of the present invention is resistant to high temperatures and will not be deactivated even if a strong exothermic reaction occurs.

[0042] (5) The catalyst of the present invention has high water resistance and can work in harsh environments without the catalyst agglomerating when in contact with water.

[0043] (6) The preparation process of the present invention is simple, reproducible, and low-cost. It can also be coupled with renewable energy for use, has a wide range of application scenarios, and is conducive to large-scale promotion and use in industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 This is a schematic diagram of the structure of the methanation catalyst provided by the present invention.

[0046] Figure 2 This is a schematic diagram of the structure of the methanation catalysts provided by the present invention after being connected in series. DETAILED DESCRIPTION

[0047] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0048] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form also includes the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0049] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Example 1

[0051] like Figure 1 As shown, this embodiment provides a methanation catalyst, including: a carrier, an active component, a binder and a pore-forming agent; the carrier is 3YSZ (3 mol% Y 2 O 3 Stable ZrO 2 ), the active component is NiO, the binder is cellulose, the pore-forming agent is starch, and the catalyst is a tubular structure with an inner diameter of 3 mm.

[0052] In this embodiment, NiO and ZrO 2 The mass ratio is 1:1.

[0053] In this embodiment, the mass ratio of the carrier, the active component, the binder, and the pore-forming agent is 100:6:9.

[0054] This embodiment also provides a method for preparing a methanation catalyst, comprising the following steps:

[0055] S1. Stir and mix the carrier, active component, binder, pore-forming agent and water into a muddy raw material, and store it in a sealed container and age it in a constant temperature and humidity environment for 30 hours;

[0056] S2, under vacuum conditions, the raw material of step S1 is cast into a green body of tubular structure by extrusion molding, and dried for 20 hours;

[0057] S3. The green body is calcined at 1100° C. and kept at this temperature for 6 hours and then cooled to room temperature to obtain a methanation catalyst.

[0058] Example 2

[0059] This embodiment provides a methanation catalyst, including: a carrier, an active component, a binder and a pore-forming agent; the carrier is ZrO 2The active component is NiO, the binder is cellulose, the pore-forming agent is starch, and the catalyst is a tubular structure with an inner diameter of 3 mm.

[0060] In this embodiment, NiO and ZrO 2 The mass ratio is 1:1.

[0061] In this embodiment, the mass ratio of the carrier, the active component, the binder, and the pore-forming agent is 100:6:9.

[0062] This embodiment also provides a method for preparing a methanation catalyst, comprising the following steps:

[0063] S1. Stir and mix the carrier, active component, binder, pore-forming agent and water into a muddy raw material, and store it in a sealed container and age it in a constant temperature and humidity environment for 30 hours;

[0064] S2, under vacuum conditions, the raw material of step S1 is cast into a green body of tubular structure by extrusion molding, and dried for 20 hours;

[0065] S3. The green body is calcined at 1100° C. and kept at this temperature for 6 hours and then cooled to room temperature to obtain a methanation catalyst.

[0066] Example 3

[0067] This embodiment provides a methanation catalyst, including: a carrier, an active component, a binder and a pore-forming agent; the carrier is 3YSZ (3 mol% Y 2 O 3 Stable ZrO 2 ), the active component is CuO, the binder is cellulose, the pore-forming agent is starch, and the catalyst is a tubular structure with an inner diameter of 3 mm.

[0068] In this embodiment, CuO and ZrO 2 The mass ratio is 1:1.

[0069] In this embodiment, the mass ratio of the carrier, the active component, the binder, and the pore-forming agent is 100:6:9.

[0070] This embodiment also provides a method for preparing a methanation catalyst, comprising the following steps:

[0071] S1. Stir and mix the carrier, active component, binder, pore-forming agent and water into a muddy raw material, and store it in a sealed container and age it in a constant temperature and humidity environment for 30 hours;

[0072] S2, under vacuum conditions, the raw material of step S1 is cast into a green body of tubular structure by extrusion molding, and dried for 20 hours;

[0073] S3. The green body is calcined at 1100° C. and kept at this temperature for 6 hours and then cooled to room temperature to obtain a methanation catalyst.

[0074] Example 4

[0075] This embodiment provides a methanation catalyst, including: a carrier, an active component, a binder and a pore-forming agent; the carrier is ZrO 2 The active component is CuO, the binder is cellulose, the pore-forming agent is starch, and the catalyst is a tubular structure with an inner diameter of 3 mm.

[0076] In this embodiment, CuO and ZrO 2 The mass ratio is 1:1.

[0077] In this embodiment, the mass ratio of the carrier, the active component, the binder, and the pore-forming agent is 100:6:9.

[0078] This embodiment also provides a method for preparing a methanation catalyst, comprising the following steps:

[0079] S1. Stir and mix the carrier, active component, binder, pore-forming agent and water into a muddy raw material, and store it in a sealed container and age it in a constant temperature and humidity environment for 30 hours;

[0080] S2, under vacuum conditions, the raw material of step S1 is cast into a green body of tubular structure by extrusion molding, and dried for 20 hours;

[0081] S3. The green body is calcined at 1100° C. and kept at this temperature for 6 hours and then cooled to room temperature to obtain a methanation catalyst.

[0082] Example 5

[0083] This embodiment provides a methanation catalyst, including: a carrier, an active component, a binder and a pore-forming agent; the carrier is 3YSZ (3 mol% Y 2 O 3 Stable ZrO 2 ), the active component is NiO, the binder is cellulose, the pore-forming agent is starch, and the catalyst is a tubular structure with an inner diameter of 2 mm.

[0084] In this embodiment, NiO and ZrO 2 The mass ratio is 1:1.

[0085] In this embodiment, the mass ratio of the carrier, the active component, the binder, and the pore-forming agent is 100:6:9.

[0086] This embodiment also provides a method for preparing a methanation catalyst, comprising the following steps:

[0087] S1. Stir and mix the carrier, active component, binder, pore-forming agent and water into a muddy raw material, and store it in a sealed container and age it in a constant temperature and humidity environment for 30 hours;

[0088] S2, under vacuum conditions, the raw material of step S1 is cast into a green body of tubular structure by extrusion molding, and dried for 20 hours;

[0089] S3. The green body is calcined at 1100° C. and kept at this temperature for 6 hours and then cooled to room temperature to obtain a methanation catalyst.

[0090] Example 6

[0091] This embodiment provides a methanation catalyst, including: a carrier, an active component, a binder and a pore-forming agent; the carrier is 3YSZ (3 mol% Y 2 O 3 Stable ZrO 2 ), the active component is NiO, the binder is cellulose, the pore-forming agent is starch, and the catalyst is a tubular structure with an inner diameter of 4 mm.

[0092] In this embodiment, NiO and ZrO 2 The mass ratio is 1:1.

[0093] In this embodiment, the mass ratio of the carrier, the active component, the binder, and the pore-forming agent is 100:6:9.

[0094] This embodiment also provides a method for preparing a methanation catalyst, comprising the following steps:

[0095] S1. Stir and mix the carrier, active component, binder, pore-forming agent and water into a muddy raw material, and store it in a sealed container and age it in a constant temperature and humidity environment for 30 hours;

[0096] S2, under vacuum conditions, the raw material of step S1 is cast into a green body of tubular structure by extrusion molding, and dried for 20 hours;

[0097] S3. The green body is calcined at 1100° C. and kept at this temperature for 6 hours and then cooled to room temperature to obtain a methanation catalyst.

[0098] Example 7

[0099] This embodiment provides a methanation reactor, which uses the methanation catalyst of any one of Embodiments 1-6 to produce CO and / or CO 2 of methanogenation.

[0100] This embodiment also provides a method for preparing a methanation reactor, comprising the following steps:

[0101] P1, such as Figure 2 As shown, the catalysts are connected by stainless steel clamps, glass sealing materials and Fe-18Cr alloy with a thickness of about 2.0 mm, and dried in an oven at 90° C. for 30 min to obtain a strip-shaped reactor, thereby realizing the scale-up of the reactor;

[0102] P2, heating the reactor assembled in step P1 to 750°C to sinter and discharge the volatiles in the sealing material, and solidifying and forming the sealing material by applying external pressure;

[0103] P3, use 1SLM nitrogen and soap bubble flowmeter to measure the high temperature air tightness of the reactor. When the leakage rate is less than 1%, it is used for CO and / or CO 2 of methanogenation.

[0104] Taking the methanation reactor prepared by the catalyst in Example 1 as an example, CO and / or CO 2 The specific process of methanogenesis is as follows:

[0105] (1) introducing hydrogen for reduction, and after NiO is reduced to Ni (about 4 hours), cooling at 1°C / min to 350°C for catalytic reaction;

[0106] (2) The gas raw material (containing a small amount of CO 2 Industrial crude synthesis gas) is introduced into the fuel mixer to make CO 2 / CO is mixed evenly with hydrogen and introduced into the assembled tubular methanation reactor. The fuel enters through the gas flow channel inside the catalytic reactor. The pressure is normal pressure. 2 / CO and hydrogen diffuse completely through the porous structure and react chemically at the reaction site (three-phase interface) to produce methane and water;

[0107] Since the tubular methanation reactor is also tolerant to steam, the source of raw materials can be wider;

[0108] (3) After the tail gas is cooled and dried, it is 2 After the absorption device (calcium lime), relatively pure methane can be obtained. In this step, the tail gas is analyzed by Agilent 7890B gas chromatography, and the analysis method is external standard method.

[0109] In order to evaluate the performance of the tubular methanation catalyst, a methanation experiment was carried out at 350°C with carbon dioxide / carbon monoxide and hydrogen as fuels and a total gas volume of 0.6 SLM in the monolithic reactor. The tail gas was dried and collected by a gas bag and analyzed by gas chromatography. Then, calculations were performed according to formulas (1)-(3), and the calculation results are shown in Table 1.

[0110] Carbon fuel conversion rate:

[0111] Methane selectivity:

[0112] Methane yield: Y CH4 =S CH4 ×X arbon Fuel ×100% (3)

[0113] In the formula, X Carbon Fuel CO or CO 2 The conversion rate, CO or CO 2 The air intake volume, CO or CO 2 Gas output, S CH4 is methane selective, is the methane flow rate at the outlet, Y CH4 is the yield of methane.

[0114] Table 1

[0115] Molar Ratio Reaction temperature (℃) Carbon fuel conversion rate (%) <![CDATA[CH 4 Yield (%)]]> <![CDATA[H 2 :CO 2 =3:1]]> 350 61 72 <![CDATA[H 2 :CO 2 =4:1]]> 350 80 80 <![CDATA[H 2 :CO=4:1]]> 350 99 90

[0116] When the ratio of carbon dioxide to hydrogen in the tubular methanation reactor increases from 3:1 to 4:1, CO 2 The conversion rate increases to 80%, and the methane yield can reach 80%. 2 When the molar ratio is 4:1, the CO conversion rate can reach 99% and the methane yield is 90%, indicating that the tubular methanation reactor has high catalytic performance and application value.

[0117] When the tubular methanation reactor was subjected to catalytic reaction at 350°C, 400°C, and 500°C, and hydrogen and CO were introduced in a ratio of 4:1, the catalytic results are shown in Table 2. It can be seen from the table that the CO conversion rates were 99%, 86%, and 75%, respectively, and the CH 4 The yields are 90%, 80% and 70% respectively. It can be seen that the catalyst of the present invention has excellent high temperature resistance and will not be deactivated even if a strong exothermic reaction occurs.

[0118] When the tubular methanation reactor was subjected to catalytic reaction at 350°C and the humidity was 3%, 5% and 10%, the catalytic results were shown in Table 2. It can be seen from the table that the CO conversion rates were 98%, 95% and 92%, respectively, and the CH 4 The yields are 88%, 85% and 80% respectively. It can be seen that with the increase of humidity, the CO conversion rate and methane yield remain at a high level, indicating that the catalyst of the present invention has excellent water resistance and can work in harsh environments without the catalyst agglomerating when it encounters water.

[0119] Table 2

[0120]

[0121] In addition, the methanation catalyst CO / CO of Examples 2-6 2 Conversion rate and CH 4 The yield performance was basically consistent with that of Example 1 after testing.

[0122] In summary, the catalyst of the present invention has a tubular structure and can achieve CO and / or CO 2 methanation, and has the ability to quickly scale up production, which is convenient for production and application; the catalyst of the present invention can adjust the H / C ratio in the feed gas according to actual conditions to control the degree of carbon dioxide conversion, has a high carbon monoxide / carbon dioxide conversion rate, a high methane yield, and a continuous and stable gas output; the active component of the catalyst of the present invention has a high degree of binding with the carrier, a good structure-activity relationship, and high stability; the catalyst of the present invention is resistant to high temperatures, and even if a strong exothermic reaction occurs, the catalyst will not be deactivated; the catalyst of the present invention has high water resistance, can work in harsh environments, and the catalyst will not agglomerate when it encounters water; the catalyst of the present invention has a long service life and can operate continuously for more than a thousand hours; the preparation process of the present invention is simple, reproducible, and low cost, and can also be coupled with renewable energy for use, has a wider range of application scenarios, and is conducive to large-scale promotion and use in industry.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A methanation catalyst, characterized in that: include: Carriers, active ingredients, binders and pore formers; The carrier includes: one or more of ZrO2 and YSZ; The active components include one or more of NiO and CuO; and the catalyst is a tubular structure.

2. The methanation catalyst according to claim 1, characterized in that The mass ratio of the carrier, active component, binder and pore-forming agent is 100:(5-7):(8-10).

3. The methanation catalyst according to claim 1, characterized in that The inner diameter of the catalyst is 2-4 mm.

4. The methanation catalyst according to claim 1, characterized in that The carrier is 3YSZ, the active component is NiO, the binder is cellulose, and the pore-forming agent is starch.

5. The method for preparing a methanation catalyst according to any one of claims 1 to 4, characterized in that: The steps include: S1, mixing the carrier, active component, binder, pore-forming agent and water into a muddy raw material and aging it for a period of time; S2, casting the raw material of step S1 into a green billet of tubular structure by extrusion molding; S3. The green body is calcined at high temperature and kept warm for a period of time and then cooled to room temperature to obtain a methanation catalyst.

6. The method for preparing a methanation catalyst according to claim 5, characterized in that: In step S1, the aging conditions include: under sealed storage, in a constant temperature and humidity environment, the aging time is 20-40 hours.

7. The method for preparing a methanation catalyst according to claim 5, characterized in that: In step S2, under vacuum conditions, the raw material of step S1 is cast into a green body with a tubular structure by extrusion molding, and then dried for 18-24 hours.

8. The method for preparing a methanation catalyst according to claim 5, characterized in that: In step S3, the high temperature calcination temperature is 1000-1200° C., and the heat preservation time is 5-8 hours.

9. A methanation reactor, characterized in that: The methanation catalyst according to any one of claims 1 to 4 is used in the methanation of CO and / or CO2.

10. The method for preparing a methanation reactor according to claim 9, characterized in that: The steps include: P1, the catalysts are connected with each other through stainless steel fixtures, sealing materials and Fe-18Cr alloy, and dried in an oven to obtain an assembled reactor; P2, heating the reactor assembled in step P1 to 700-800°C to sinter and discharge the volatiles in the sealing material, and solidifying and forming the sealing material by external pressure; P3. Use SLM nitrogen and soap bubble flowmeters to measure the high temperature gas tightness of the reactor. When the leakage rate is less than 1%, it is used for the methanation of CO and / or CO2.

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