Preparation method of Ru / ZrO2 catalyst for CO selective methanation

Abstract

The invention relates to a catalyst preparation technology, and aims to provide a preparation method of a Ru / ZrO2 catalyst for CO selective methanation. Comprising the following steps: adding a zirconium source and a mineralizing agent into a solvent, and uniformly stirring to obtain a mixed solution; centrifuging and washing a product obtained after the crystallization reaction to obtain a solid product; the product is in a rod-like monoclinic crystal form; the preparation method comprises the following steps: loading metal Ru on the surface of rod-like monoclinic zirconium oxide in an equivalent-volume impregnation manner, and drying and roasting to obtain a Ru / ZrO2 catalyst; in the catalyst, the loading amount of Ru is 0.1-2 wt%. According to the catalyst, Ru nano-particles can be stabilized in a reaction atmosphere, so that the structural stability of the catalyst is maintained, and when the catalyst is applied to CO selective methanation hydrogen purification, the selectivity and stability of CO methanation can be remarkably improved, the service life of the catalyst is prolonged, and the CO concentration in feed gas can be greatly increased.

Description

Technical Field

[0001] This invention relates to the field of catalyst preparation technology, and more particularly to the preparation of a Ru / ZrO2 catalyst for selective methanation of CO. Background Technology

[0002] There are many methods for industrial hydrogen production through reforming, such as steam reforming, which is one of the most common industrial methods. Its basic principle is to use a catalyst to react natural gas (usually methane), methanol, etc., with steam to produce hydrogen and carbon dioxide, typically with a small amount of carbon monoxide. The presence of CO in the reformed gas greatly limits the application of hydrogen, especially in low-temperature fuel cells, where even small amounts of CO can poison the fuel cell catalyst (CO tolerance concentration < 10 ppm), reducing its lifespan. Therefore, effectively removing carbon monoxide from the reformed gas is crucial.

[0003] Methods for purifying hydrogen include membrane separation technology, CO preferential oxidation (PROX), and CO selective methanation (CO-SMET): 1. Membrane separation technology: This technology uses Pd membranes to purify hydrogen, but it has high cost, low flux, and poor durability; 2. PROX: Currently, supported Ru catalysts and Pt-based alloy catalysts have been successfully developed for PROX. These catalysts often operate at a wide reaction temperature range and at low temperatures, which can easily cause reverse water-gas shift reaction. Furthermore, this reaction process requires the introduction of additional air, making the operating system complex and posing safety hazards; 3. Carbon monoxide selective methanation: This method can selectively convert CO to methane in situ without the need for additional gas sources. It is convenient to operate, low in cost, and highly safe.

[0004] Although CO selective methanation is a simple, safe, and low-cost method for hydrogen purification, traditional catalysts suffer from poor stability and low CO selectivity. This is because industrially reformed hydrogen contains not only a small amount of CO but also a large amount of CO2, thus requiring catalysts with high selectivity for CO methanation. Furthermore, the industrial hydrogen purification process involves water vapor, which can easily cause sintering of the active metal in the catalyst, leading to a decrease in CO selective methanation activity. Therefore, there is an urgent need to develop a highly selective and stable CO selective methanation catalyst. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for preparing a Ru / ZrO2 catalyst for selective CO methanation.

[0006] To solve the technical problem, the solution of the present invention is:

[0007] A method for preparing a Ru / ZrO2 catalyst for selective CO methanation is provided, comprising the following steps:

[0008] (1) Add zirconium source and mineralizer to solvent and stir evenly to obtain mixed solution; the zirconium source is zirconium oxynitrate hydrate and the mineralizer is sodium hydroxide; the molar ratio of zirconium source to mineralizer is 0.01~10.00:0.01~10.00;

[0009] (2) The mixed solution is transferred to a hydrothermal reactor for crystallization reaction; the reaction product is centrifuged and washed to obtain a solid product; the product is in the form of rod-shaped monoclinic crystals and is called rod-shaped monoclinic zirconium oxide (i.e., m-ZrO2-nanorod).

[0010] (3) Metal Ru was loaded onto the surface of rod-shaped monoclinic zirconium oxide by equal volume impregnation, and then dried and calcined to obtain Ru / ZrO2 catalyst; the Ru loading in the catalyst was 0.1 to 2 wt%.

[0011] In a preferred embodiment of the present invention, the solvent in step (1) is water.

[0012] As a preferred embodiment of the present invention, in step (2), the crystallization reaction temperature is controlled to be 150-200°C and the reaction time is 2-48 h.

[0013] As a preferred embodiment of the present invention, in step (2), the solid obtained by centrifugation is washed with deionized water.

[0014] As a preferred embodiment of the present invention, in step (3), equal volume impregnation refers to dissolving the loaded metal precursor nitrate or chloride in water to obtain a metal precursor solution; then immersing the zirconium oxide solid powder in the metal precursor solution and ultrasonically treating it.

[0015] As a preferred embodiment of the present invention, in step (3), the concentration of metallic Ru in the precursor solution and the power and time of ultrasonic treatment are controlled so that the Ru loading in the final catalyst meets the requirements.

[0016] As a preferred embodiment of the present invention, in step (3), drying and calcining specifically refers to: transferring the liquid-solid mixture that has completed the impregnation treatment to an oven and drying it at 60-100°C for 6-10 h; then transferring the solid to a muffle furnace and calcining it at 400-600°C for 2-4 h.

[0017] This invention further provides a method for selective CO methanation using the Ru / ZrO2 catalyst prepared by the aforementioned method, comprising the following steps:

[0018] (1) A fixed bed of Ru / ZrO2 catalyst with a mesh size of 40-60 is loaded into the reaction tube, and then hydrogen is continuously introduced for pre-reduction treatment;

[0019] (2) A reaction gas is continuously introduced into the reaction tube to carry out the reaction. The reaction gas contains CO, CO2, H2, water vapor and equilibrium gas. Under the action of Ru / ZrO2 catalyst, CO is selectively hydrogenated to CH4, while avoiding the hydrogenation reaction of CO2 in the reaction gas, thereby reducing the consumption of H2 in the reaction gas.

[0020] As a preferred embodiment of the present invention, the temperature during the pre-reduction treatment is controlled to be 250-600°C and the time is 0.5-4h.

[0021] As a preferred embodiment of the present invention, the CO content in the reaction gas is 10 ppm to 10.0 vol%, the CO2 content is 5 to 25 vol%, the H2 content is 20 to 70 vol%, the water vapor content is 1 to 20 vol%, and the equilibrium gas is one or more of N2, He, and Ar; the reaction gas space velocity is controlled at 1000 to 30000 mL·g. -1 ·h -1 The reaction pressure is 0.1–0.5 MPa, and the reaction temperature is 50–400℃.

[0022] Description of the invention principle:

[0023] 1. According to existing literature, catalysts with smaller Ru metal clusters have higher CO methanation selectivity. Therefore, it is of great significance to design and prepare metal catalysts with excellent structural stability, anti-sintering and anti-leakage under harsh reaction conditions.

[0024] In existing technologies, zirconium oxide is synthesized using zirconium sources and mineralizers, and further loaded with metallic Ru to prepare catalysts. For example, Chinese invention application CN119528123A proposes a tandem method for carbon dioxide hydrogenation methanation-cracking to produce carbon, in which a mixture of CO2 and H2 is reacted with a catalyst to hydrogenate CO2 to CH4. This document mentions the application of a Ru / ZrO2 catalyst. Unlike this document, this invention aims to selectively hydrogenate CO to CH4 while avoiding the hydrogenation reaction of CO2 in the reaction gas, thereby reducing the consumption of H2 in the reaction gas. Clearly, the application direction of the Ru / ZrO2 catalyst in this document is completely opposite to that of this invention and cannot achieve the specific technical objective.

[0025] Different types of ZrO2 supports require different hydrothermal synthesis conditions, and the morphology and crystal orientation of the supports are highly sensitive to hydrothermal conditions. Through long-term and in-depth research, the applicant's R&D team proposed an innovative preparation method based on Ru / ZrO2 catalysts: by finely adjusting the type and amount of zirconium source and mineralizer, the crystal form can be controlled, ensuring the synthesis of rod-shaped monoclinic ZrO2 supports with low-index crystal orientations and a high content of surface hydroxyl groups. In subsequent verification experiments, the morphology of the ZrO2 support was determined using XRD and TEM morphology characterization techniques, and the surface hydroxyl content of the ZrO2 support was further determined using vacuum transmission infrared spectroscopy, confirming that the rod-shaped monoclinic ZrO2 support has a high number of low-index crystal orientations. Specifically, low-index crystal orientations refer to (-1 1 1) and (1 1 1) crystal faces. These low-index crystal faces often contain a high number of surface hydroxyl groups, thereby supporting and stabilizing metallic Ru particles, preparing a catalyst that meets the specific application objectives of this invention.

[0026] Considering that supports with different morphologies exhibit varying adsorption and desorption capacities for reactants and products, as well as different interactions with the active metal Ru, this invention rationally designs rod-shaped monoclinic zirconium oxide (m-ZrO2-nanorod, where m represents monoclinic crystal system) by controlling the crystal orientation of ZrO2. This zirconium oxide exhibits strong adsorption of CO, weak adsorption of CO2, and a strong metal-support interaction with Ru. This specific crystalline form of zirconium oxide can better stabilize Ru metal nanoparticles. After being used as a support for further synthesis of Ru / ZrO2 catalysts, it demonstrates excellent performance with high stability, high activity, and high selectivity in the selective methanation reaction of CO. Compared with traditional CO selective methanation catalysts in the prior art, the Ru / ZrO2 (m-ZrO2-nanorod) catalyst of this invention has the technical advantages of high stability, high activity, and high selectivity.

[0027] 2. The catalyst used in this invention is supported by rod-shaped monoclinic zirconium oxide with a high specific surface area, which ensures uniform dispersion of metal particles. The small ruthenium nanoclusters are beneficial to improving the selectivity of CO methanation. The supported Ru metal is a metal component with high hydrogen dissociation activity. This invention uses rod-shaped monoclinic zirconium oxide with high specific surface area supported on Ru metal as a catalyst. It can utilize the high metal dispersion and hydrogen enrichment capacity to hydrogenate CO to CH4. At the same time, the proportion of CO2 methanation is very small, and most of the methane in the product comes from CO hydrogenation, ultimately achieving higher CO methanation selectivity. The excellent performance of this catalyst stems from: the strong adsorption of CO by the rod-shaped monoclinic zirconium oxide support, resulting in high reactivity; the weak adsorption capacity of the rod-shaped monoclinic zirconium oxide support for CO2, resulting in high CO methanation selectivity; and the strong metal-support interaction between the rod-shaped monoclinic zirconium oxide support and Ru metal, which makes it difficult for Ru metal to agglomerate during the reaction, thus extending the catalyst's lifespan.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. This invention provides a Ru / ZrO2 catalyst for selective CO methanation. According to the reaction performance test, the Ru catalyst supported on the rod-shaped monoclinic zirconium oxide support (m-ZrO2-nanorod) of this invention can stabilize Ru nanoparticles in the reaction atmosphere, thereby maintaining the stability of the catalyst structure. When applied to selective CO methanation for hydrogen purification, it can significantly improve the selectivity and stability of CO methanation.

[0030] 2. Using the Ru / m-ZrO2-nanorod catalyst provided by this invention, the CO concentration in the feed gas can be reduced to as low as 10 ppm, and the CH4 selectivity in the reaction process is as high as 100%, with a catalyst operating life of up to 1500 h. Attached Figure Description

[0031] Figure 1 The image shown is an electron microscope image of the rod-shaped monoclinic zirconia prepared in Examples 1-6 of this invention.

[0032] Figure 2 This is an electron microscope image of the spherical monoclinic zirconia obtained in Comparative Example 4-2.

[0033] Figure 3 This is an electron microscope image of the sheet-like monoclinic zirconia obtained in Comparative Example 4-4.

[0034] Figure 4 These are electron microscope images of tetragonal monoclinic zirconia prepared in Comparative Examples 4-7.

[0035] Figure 5 These are electron microscope images of the long columnar monoclinic zirconia prepared in Comparative Examples 4-8. Figure 6 These are XRD characterization diagrams of spherical monoclinic zirconium oxide (ZrO2-sphere), sheet-like monoclinic zirconium oxide (ZrO2-sheet), and rod-like monoclinic zirconium oxide (ZrO2-nanorod). Detailed Implementation

[0036] The present invention will now be described in further detail with reference to specific embodiments. These embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way.

[0037] Part One: Implementation Scheme of the Invention

[0038] 1. Preparation of Ru / ZrO2 catalyst

[0039] This invention proposes a method for preparing a Ru / ZrO2 catalyst for selective CO methanation, comprising the following steps:

[0040] (1) Add zirconium oxynitrate hydrate, which is used as zirconium source, and sodium hydroxide, which is used as mineralizing agent, to water and stir until homogeneous to obtain a mixed solution; the molar ratio of zirconium source to mineralizing agent is 0.01~10.00:0.01~10.00.

[0041] (2) The mixed solution was transferred to a hydrothermal reactor for crystallization reaction; the reaction temperature was 150-200℃ and the reaction time was 2-48 h. The reaction product was centrifuged and washed with deionized water to obtain a solid product; the product was in the form of rod-shaped monoclinic crystals and was called rod-shaped monoclinic zirconium oxide (i.e., m-ZrO2-nanorod).

[0042] (3) Metal Ru was loaded onto the surface of rod-shaped monoclinic zirconium oxide by equal volume impregnation, and then dried and calcined to obtain Ru / ZrO2 catalyst; the Ru loading in the catalyst was 0.1 to 2 wt%.

[0043] The equal-volume impregnation process involves dissolving the supported metal precursor nitrate or chloride in water to obtain a metal precursor solution; then immersing the zirconium oxide solid powder in the metal precursor solution and ultrasonically treating it. The concentration of Ru in the precursor solution, as well as the power and time of the ultrasonic treatment, are controlled to ensure that the Ru loading in the final catalyst meets the requirements.

[0044] The drying and calcination specifically refers to: transferring the liquid-solid mixture that has undergone impregnation treatment to an oven and drying it at 60-100°C for 6-10 hours; then transferring the solid to a muffle furnace and calcining it at 400-600°C for 2-4 hours.

[0045] 2. Application of Ru / ZrO2 catalyst

[0046] This invention proposes a method for selective CO methanation using the Ru / ZrO2 catalyst prepared by the aforementioned method, comprising the following steps:

[0047] (1) A fixed bed of Ru / ZrO2 catalyst with a mesh size of 40-60 is loaded into the reaction tube, and then hydrogen is continuously introduced for pre-reduction treatment; the treatment temperature is controlled at 250-600℃ and the time is 0.5-4 h.

[0048] (2) A reaction gas is continuously introduced into the reaction tube to carry out the reaction. The reaction gas contains CO, CO2, H2, water vapor and equilibrium gas. Under the action of Ru / ZrO2 catalyst, CO is selectively hydrogenated to CH4, while avoiding the hydrogenation reaction of CO2 in the reaction gas, thereby reducing the consumption of H2 in the reaction gas.

[0049] As an example, the CO content in the reaction gas is 10 ppm to 10.0 vol%, the CO2 content is 5 to 25 vol%, the H2 content is 20 to 70 vol%, the water vapor content is 1 to 20 vol%, and the equilibrium gas is one or more of N2, He, and Ar; the reaction gas space velocity is controlled at 1000-30000 mL·g. -1 ·h -1 The reaction pressure is 0.1–0.5 MPa, and the reaction temperature is 50–400℃.

[0050] Unless otherwise specified, the raw materials, apparatus, and equipment used in this invention are all commonly used in the field; unless otherwise specified, the methods used in this invention are all conventional methods in the field.

[0051] Part Two: Examples and Comparative Cases

[0052] 1. Embodiments of the present invention

[0053] In the following embodiments, the synthesis of the support was carried out in a closed container, the synthesis of the catalyst was carried out in an open container, and the catalytic hydrogenation reaction was carried out in a fixed-bed reactor. The synthesis and application methods of the support and catalyst are as described in the first part above, and the specific preparation conditions or parameters are shown in Tables 1-3.

[0054]

[0055] In Table 2, the support m-ZrO2-nanorod-1-1 refers to the product obtained from Example 1-1, and so on. That is, Examples 2-1 to 2-11 used the zirconia prepared in Examples 1-1 to 1-11 of Table 1 as supports. Examples 2-12 to 2-14 used the zirconia prepared in Examples 1-2, 1-5, and 1-8, respectively.

[0056]

[0057] In Table 3, Examples 3-1 to 3-14 used the catalysts prepared in Examples 2-1 to 2-14 of Table 2, respectively. Examples 3-15 to 3-17 used the catalysts prepared in Example 2-13 of Table 2. Examples 3-18 to 3-20 used the catalysts prepared in Example 2-14.

[0058] In Table 3, the balancing gas used in Examples 3-2, 3-5, 3-9, 3-12, 3-15, and 3-18 is N2; the balancing gas used in Examples 3-1, 3-3, 3-4, 3-6, 3-7, and 3-8 is He; and the balancing gas used in Examples 3-10, 3-11, 3-13, 3-14, 3-16, 3-17, 3-19, and 3-20 is Ar.

[0059]

[0060] As can be seen from Table 3, when the Ru loading in the Ru / ZrO2 catalyst of the present invention is 0.1–2 wt%, the catalyst generally exhibits superior performance in the selective hydrogenation of CO, achieving a CO conversion rate and CH4 selectivity close to 100%, and the optimal Ru loading is 1 wt%. Therefore, 0.1–2 wt% is taken as the Ru loading range of the present invention, and the optimal loading is 1 wt%.

[0061] 2. Comparative Example

[0062] Considering that different supports have different adsorption and desorption capacities for reactants and products, and different forces on active metal Ru, this invention controls the orientation of ZrO2 crystal faces by changing the type and amount of zirconium source and mineralizer, and obtains Ru / ZrO2 catalysts supported on supports with various crystal structures.

[0063] That is, referring to the preparation method and reaction parameters of this invention, different catalysts were obtained by loading the same proportion of metallic ruthenium onto the surface of zirconium oxide with different morphologies. These catalysts were then used in the selective hydrogenation reaction of CO under the same reaction conditions to test the catalytic performance of each catalyst. Specifically, as follows:

[0064] (1) Preparation of zirconia supports with other crystal structures

[0065] The zirconium source should be selected from the following options: zirconium oxynitrate hydrate (ZrO(NO3)2·xH2O), zirconium n-butoxide (C 16 H 36Zirconium boride (Zr2Zr), zirconium carbonate (ZrCO3), zirconium oxychloride hydrate (ZrOCl2·xH2O), and zirconium sulfate hydrate (Zr(SO4)2·xH2O);

[0066] The mineralizing agent should be selected from the following options: ammonium chloride (NH4Cl), ammonium fluoride (NH4F), ammonium nitrate (NH4NO3), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, ammonia (NH3·H2O), urea (CO(NH2)2), boric acid (H3BO3), sodium tetrafluoroborate (NaBF4), potassium hydroxide (KOH), and sodium hydroxide (NaOH).

[0067] The specific crystal forms of the prepared zirconia are as follows: 4-2 and 4-3 are spherical monoclinic zirconia (i.e., m-ZrO2-sphere); 4-4 is plate-like monoclinic zirconia (i.e., m-ZrO2-sheet); 4-5 and 4-6 are spindle-shaped monoclinic zirconia (m-ZrO2-spindle-shaped); 4-7 is tetragonal monoclinic zirconia (m-ZrO2-tetragonal); 4-8 is long columnar monoclinic zirconia (m-ZrO2-long columnar); 4-9 is disc-shaped monoclinic zirconia (m-ZrO2-disc-shaped); and 4-10 is spherical tetragonal zirconia (t-ZrO2-sphere). Samples of the above-mentioned spherical, plate-like, and rod-shaped monoclinic zirconia were taken and characterized by XRD (e.g., ...). Figure 6 As shown in Table 4, the statistical results of the proportion of low-index crystal plane orientations of different types of ZrO2 supports are as follows.

[0068]

[0069] Analysis of the data in Table 4 shows that the rod-shaped monoclinic zirconia support of the present invention has a large number of low-index crystal planes. These low-index crystal planes often contain a large number of surface hydroxyl groups, which can support and stabilize metal Ru particles, making it far superior to other crystalline zirconia-supported ruthenium catalysts.

[0070] (2) Metal Ru was loaded onto the surface of each zirconium oxide support by equal volume impregnation, and different Ru / ZrO2 catalysts were obtained after drying and calcination. The Ru loading was 0.5 wt%.

[0071] (3) Perform the CO selective methanation reaction according to the application method described in this invention.

[0072] During the reaction, the reaction pressure was controlled at 0.1 MPa, the reaction temperature at 200°C, and the reaction time at 10 hours. Other reaction conditions are shown in Table 5.

[0073] In this table, number 5-1 is a Ru / ZrO2 catalyst supported by rod-shaped monoclinic zirconium oxide (i.e., m-ZrO2-nanorod) (i.e., the catalyst in Example 3-11); numbers 5-2 to 5-10 are Ru / ZrO2 catalysts supported by other crystalline zirconium oxides.

[0074]

[0075] Analysis of the data in Tables 3 and 5 shows that the rod-shaped monoclinic zirconia supported ruthenium catalyst of the present invention exhibits excellent performance in the hydrogenation reaction. In Example 5-1, the CO conversion rate is close to 100% and the CH4 selectivity is as high as 99.5%, which is far superior to other crystalline zirconia supported ruthenium catalysts.

[0076] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for the preparation of a Ru / Zr02 catalyst for CO-selective methanation, characterized in that, The method comprises the following steps: (1) adding a zirconium source and a mineralizer into a solvent to obtain a mixed solution after stirring uniformly; the zirconium source is zirconyl nitrate hydrate, and the mineralizer is sodium hydroxide; the molar ratio of the zirconium source to the mineralizer is 0.01-10.00:0.01-10.00; (2) transferring the mixed solution into a hydrothermal kettle to perform a crystallization reaction; a solid product is obtained after centrifugation and washing treatment of the reaction product; the product presents a rod-like monoclinic crystal shape and is called rod-like monoclinic zirconium oxide; (3) loading metal Ru on the surface of the rod-like monoclinic zirconium oxide in an equal-volume impregnation manner, and obtaining a Ru / ZrO2 catalyst after drying and calcination; in the catalyst, the Ru loading amount is 0.1-2 wt%.

2. The method of claim 1, wherein, In the step (1), the solvent is water.

3. The method of claim 1, wherein, In the step (2), the crystallization reaction temperature is controlled to be 150-200 ℃, and the reaction time is 2-48 h.

4. The method of claim 1, wherein, In the step (2), the obtained solid is washed by using deionized water after centrifugation treatment.

5. The method of claim 1, wherein, In the step (3), the equal-volume impregnation refers to dissolving a metal precursor nitrate or chloride in water to obtain a metal precursor solution; then, the zirconium oxide solid powder is immersed in the metal precursor solution and subjected to ultrasonic treatment.

6. The method of claim 5, wherein, In the step (3), the concentration of the metal Ru in the precursor solution and the power and time of the ultrasonic treatment are controlled to make the Ru loading amount in the final catalyst meet the requirements.

7. The method of claim 1, wherein, In the step (3), the drying and calcination specifically refer to: moving the liquid-solid mixture after completing the impregnation treatment into an oven for drying treatment at 60-100 ℃ for 6-10 h; then, moving the solid into a muffle furnace for calcination at 400-600 ℃ for 2-4 h.

8. A method for selective methanation of CO using a Ru / ZrO2 catalyst prepared by the method of claim 1, characterized in that, The method comprises the following steps: (1) loading 40-60 mesh Ru / ZrO2 catalyst into a reaction tube to construct a fixed bed, and then continuously feeding hydrogen for pre-reduction treatment; (2) continuously feeding reaction gas into the reaction tube for reaction, the reaction gas comprising CO, CO2, H2, water vapor and balance gas; under the action of the Ru / ZrO2 catalyst, CO is selectively hydrogenated into CH4, and the hydrogenation reaction of CO2 in the reaction gas is avoided, so as to reduce the consumption of H2 in the reaction gas.

9. The method of claim 8, wherein, The temperature during the pre-reduction treatment is controlled to be 250-600 ℃, and the time is 0.5-4 h.

10. The method of claim 8, wherein, The CO content in the reaction gas is 10 ppm to 10.0 vol%, the CO2 content is 5 to 25 vol%, the H2 content is 20 to 70 vol%, the water vapor content is 1 to 20 vol%, and the balance is one or more of N2, He, and Ar; the reaction gas space velocity is controlled to be 1000 to 30000 mL.g -1 ·h -1 -1, the reaction pressure is 0.1 to 0.5 MPa, and the reaction temperature is 50 to 400 DEG C.

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