Preparation method and application of oxide / ni reverse catalyst

Abstract

The application discloses a preparation method and application of an Oxide / Ni reverse catalyst, and belongs to the technical field of dry reforming of methane and carbon dioxide to prepare synthesis gas. In the application, nitrate of metal is infiltrated on bulk nickel powder by a melting infiltration method, metal oxides are loaded on the bulk nickel carrier after air calcination, and finally the Oxide / Ni reverse catalyst is obtained through hydrogen reduction. The magnesium-doped alumina / nickel reverse catalyst (MgAlO x / Ni-1) with a structure optimized in the application has the advantages that in the reaction of dry reforming of methane and carbon dioxide to prepare synthesis gas, the initial conversion rates of methane and carbon dioxide are close to the thermodynamic equilibrium conversion rate, and the proportion of hydrogen and carbon monoxide in the product is close to 1:1; the catalyst has a CH4 conversion rate of 70% after running for more than 200 hours under the condition of 800 DEG C, 79,000 mL.g ‑1 .h ‑1 -1.h-1, and has excellent stability. The preparation method of the catalyst in the application is simple and reliable, raw materials are easy to obtain, and the catalyst has universality.

Description

Technical Field

[0001] This invention belongs to the field of methane-carbon dioxide dry reforming to prepare syngas, specifically relating to a method for preparing an Oxide / Ni reverse catalyst and its application. Background Technology

[0002] Dry reforming (DRM) of methane converts methane (CH4) and carbon dioxide (CO2) into syngas (H2 / CO), which can then be further processed into valuable chemicals, making this process significant for both environmental and economic reasons. Compared to precious metals such as platinum or rhodium, nickel-based catalysts exhibit high activity and lower cost for methane cracking, and are therefore commonly used in DRM. Despite these advantages, Ni-catalyzed DRM faces significant challenges, particularly catalyst deactivation due to sintering and carbon deposition. This sintering problem is especially severe in oxide-supported nickel-based nanocatalysts, as Ni particles (Tammann temperature = 632 °C) readily sinter at typically high reaction temperatures (750–1000 °C). Simultaneously, carbonaceous material produced by methane decomposition (CH4 → C + 2H2) and the Boudouard reaction (2CO → C + CO2) accumulates around active sites, forming "dead carbon" and leading to deactivation. For oxide-supported nickel-based catalysts, strategies such as nanostructuring, alloying, and spatial confinement can slow down the sintering process of Ni; while appropriate functionalization modification of the oxide support can also help reduce carbon deposition. Although there are numerous reports on oxide-supported nickel-based catalysts, no effective method has yet been found to completely solve the problem of catalyst deactivation caused by sintering and carbon deposition.

[0003] Considering the inherent limitations of supported nickel-based catalysts, the use of bulk Ni as the active component in reverse catalysts has attracted some attention. Thomas et al. (L. Sandoval-Diaz, D. Cruz, M. Vuijk, G. Ducci, M. W.Jiang,M.Plodinec,A.Hammud,D.Ivanov,T. K.Reuter,R. C. Scheuer, A. Knop-Gericke, T. Lunkenbein, Nature Catalysis 2024, 7, 161-171. used in-situ environmental scanning electron microscopy (ESEM) and near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) to observe the oscillatory phenomenon of the DRM reaction on nickel foil, finding that pure nickel surfaces possess catalytic activity for DRM, laying the foundation for the development of nickel-based reverse catalysts. Lu et al. (L. Cai, S. Han, W. Xu, S. Chen, X. Shi, J. Lu, Angewandte Chemie International Edition 2024, 63.) used atomic layer deposition (ALD) to coat a porous alumina layer on Ni / MgAl2O4, and the reverse interface enhanced the stability and activity of the catalyst in DRM and propane dehydrogenation. These results indicate that nickel-based reverse catalysts have great application potential in DRM. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing an Oxide / Ni reverse catalyst and its application. This invention constructs an Oxide / Ni reverse catalyst composed of bulk Ni modified with oxide nanostructures. In the DRM reaction process, the bulk Ni in the reverse catalyst acts as a support and does not sinter, and can maintain the surface Ni during the reaction. 0 The active sites exhibit structural stability, and the supported oxide possesses a higher Tammann temperature, resisting sintering and significantly stabilizing the surface Ni active sites. This combination effectively addresses the sintering problem in DRM. Furthermore, the alkali metal doping strategy reduces the surface acidity of the catalyst, thereby mitigating carbon accumulation during the reaction, even under high temperature (800℃), high reactant concentrations (40% CH4 and 40% CO2), and high space velocities (79,000 mL·g⁻¹). -1 ·h -1 Under the conditions of ) optimized MgAlO x The / Ni-1 reverse catalyst maintained a 70% CH4 conversion rate after running for more than 260 hours, demonstrating good DRM catalytic stability.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] This invention provides a method for preparing a supported Oxide / Ni inverted catalyst, comprising the following steps:

[0007] (1) Mix the precursor of the metal oxide with the bulk nickel in a certain proportion and grind them evenly. Add 1 to 2 drops of deionized water to the resulting powder.

[0008] (2) The mixed powder obtained in step (1) is vacuum dried for 24 to 72 hours to obtain a mixed powder precursor;

[0009] (3) The mixed powder precursor obtained in step (2) is calcined in air at 500-1000℃ for 1-3 hours to obtain Oxide / NiO sample;

[0010] (4) The Oxide / NiO sample obtained in step (3) is reduced in a hydrogen atmosphere at 550-750℃ for 1-3 hours. After cooling to 25-50℃, it is purged in an O2 / Ar atmosphere for 0.5-2 hours for passivation treatment to obtain the Oxide / Ni reverse catalyst.

[0011] In the above technical solution, the precursor of the metal oxide in step (1) is at least one of magnesium, aluminum nitrate, chlorate, acetate, sulfate, and organic salt.

[0012] In the above technical solution, the metal oxide mentioned in step (1) has a mass percentage of 0.5wt% to 50wt% in the entire catalyst, preferably 1wt% to 30wt%.

[0013] In the above technical solution, the metal oxide mentioned in step (1) is an oxide of magnesium and aluminum, and the mass ratio of magnesium to aluminum is 1:5 to 5:1.

[0014] In the above technical solution, the bulk nickel mentioned in step (1) is at least one of nickel metal powder and nickel oxide powder.

[0015] In the above technical solution, the temperature of vacuum drying in step (2) is further controlled at 60-90°C.

[0016] In the above technical solution, the calcination temperature in step (3) is 750-850℃ and the heating rate is 1-5℃ / min.

[0017] In the above technical solution, the temperature of the reduction treatment in step (4) is 600-700℃, the heating rate is 2-10℃ / min, and the H2 flow rate is 20-100ml / min.

[0018] In the above technical solution, further, the O2 / Ar atmosphere in step (4) is a mixture of oxygen and argon with a volume ratio of 1:99 to 10:90.

[0019] The present invention provides a supported Oxide / Ni inverted catalyst prepared by the above preparation method.

[0020] In the above technical solution, the catalyst further includes an oxide and a bulk Ni support, and the oxide exists in the form of nanoparticles and nanosheets.

[0021] In the above technical solution, the particle size of the bulk Ni support is 10-1000 nm; the particle size of the oxide nanoparticles is 3-50 nm; and the thickness of the oxide nanofilm is 1-10 nm.

[0022] The present invention also provides the application of the above-mentioned supported Oxide / Ni reverse catalyst in the dry reforming of methane and carbon dioxide to produce syngas.

[0023] In the above technical solution, the preparation of syngas by dry reforming of methane and carbon dioxide is further carried out in a fixed bed or a moving bed.

[0024] In the above technical solution, the reaction conditions for the dry reforming of methane and carbon dioxide to prepare syngas are further as follows: reaction pressure is 0.01-1 MPa, reaction gas ratio is CH4:CO2:N2 = 1-3:3-1:1, and reaction gas flow rate is 10,000-80,000 mL·g -1 ·h -1 The reaction temperature is 750–850℃.

[0025] The beneficial effects of this invention are as follows:

[0026] 1. In the reverse catalyst of the present invention, the reverse interface structure promotes the stability of active sites, inhibits the sintering of oxides and Ni supports, eliminates the negative impact of sintering on catalytic performance, and exhibits activity exceeding thermodynamic equilibrium conversion and good stability in the DRM reaction.

[0027] 2. By reducing the acidity of the catalyst surface through Mg doping, the amount of carbon deposited during the reaction process is reduced, enabling the catalyst to maintain a high CH4 and CO2 conversion rate and operate stably for more than 200 hours.

[0028] 3. The preparation method of this invention is simple, uses inexpensive raw materials, and has strong versatility and industrial application potential. Attached Figure Description

[0029] Figure 1 AlO in Example 1 x XRD pattern of the Ni-1 reverse catalyst;

[0030] Figure 2 AlO in Example 1 x TEM image of the Ni-1 reverse catalyst;

[0031] Figure 3 AlO in Example 1x Stability test diagram of / Ni-1 catalyst in methane-carbon dioxide dry reforming reaction;

[0032] Figure 4 MgAlO in Example 2 x XRD pattern of the Ni-1 reverse catalyst;

[0033] Figure 5 MgAlO in Example 2 x HADDF-STEM image of the Ni-1 reverse catalyst;

[0034] Figure 6 MgAlO in Example 2 x Elemental mapping image of the Ni-1 inverted catalyst;

[0035] Figure 7 MgAlO in Example 2 x Stability test diagram of / Ni-1 catalyst in methane-carbon dioxide dry reforming reaction;

[0036] Figure 8 AlO in Example 3 x Stability test diagram of / Ni-2 catalyst in methane-carbon dioxide dry reforming reaction;

[0037] Figure 9 MgAlO in Example 4 x Stability test diagram of / Ni-2 catalyst in methane-carbon dioxide dry reforming reaction;

[0038] Figure 10 This is a stability test diagram of the Ni / Al2O3 catalyst in the dry reforming reaction of methane and carbon dioxide in Comparative Example 1.

[0039] Figure 11 The graph shows the stability test results of the Ni / MgAl2O4 catalyst in the dry reforming reaction of methane and carbon dioxide in Comparative Example 2. Detailed Implementation

[0040] The present invention will now be described in detail through embodiments, but the scope of the claims is not limited to these embodiments. Furthermore, the embodiments only provide some conditions for achieving this objective and do not imply that all conditions must be met to achieve this objective.

[0041] Example 1

[0042] (1) Place 1.0g NiO powder and 1.5g Al(NO3)3·9H2O into an agate mortar and grind for 10 minutes;

[0043] (2) Transfer the resulting mixture to a 10 mL glass vial, add 1-2 drops of deionized water to the resulting powder, and then treat it in a vacuum oven at 90 °C for 48 hours.

[0044] (3) The mixture was heated to 800°C in a muffle furnace at a rate of 2°C / min and held at this temperature for 2 hours. The resulting product was labeled as AlO. x / NiO-1;

[0045] (4) AlO x The NiO-1 sample was heated to 650℃ at a rate of 5℃ / min in a pure H2 atmosphere (50 mL / min) and held for 2 hours. After cooling to 25–50℃, it was passedivated by purging with an O2 / Ar atmosphere (a mixture of oxygen and argon in a volume ratio of 5 / 95) for 1 hour to obtain AlO. x / Ni-1 reverse catalyst;

[0046] (5) The obtained AlO x In the application of the / Ni-1 reverse catalyst in the dry reforming of methane and carbon dioxide to produce syngas, the reaction conditions are as follows: the reaction is carried out in a fixed-bed reactor containing the catalyst, the catalyst dosage is 50 mg, the reaction pressure is 0.1 MPa, the reaction gas ratio is CH4:CO2:N2 = 2:2:1, the reaction gas flow rate is 50 mL / min, and the reaction temperature is 800 °C.

[0047] AlO in Example 1 x X-ray diffraction pattern of NiO-1 reverse catalyst ( Figure 1 ) and transmission electron microscopy ( Figure 2 Characterization shows that AlO x Uniformly distributed on the Ni support, AlO x The average particle size distribution of the nanoparticles is around 10 nm, while the particle size distribution of the Ni support ranges from 50 to 500 nm. DRM performance evaluation results show ( Figure 3 After 60 hours of reaction, the conversion rate of CH4 decreased from 93.9% to 83.1%, indicating good stability.

[0048] Example 2

[0049] (1) Place 1.0g NiO powder, 0.34g Mg(NO3)2·6H2O and 1.35g Al(NO3)3·9H2O into an agate mortar and grind for 10 minutes;

[0050] (2) Transfer the resulting mixture to a 10 mL glass vial, add 1-2 drops of deionized water to the resulting powder, and then treat it in a vacuum oven at 90 °C for 48 hours.

[0051] (3) The mixture was heated to 800°C in a muffle furnace at a rate of 2°C / min and held at this temperature for 2 hours. The resulting product was labeled as MgAlO. x / NiO-1;

[0052] (4) MgAlO x The NiO-1 sample was heated to 650℃ in a pure H2 atmosphere (50 mL / min) at a rate of 5℃ / min and held for 2 hours. After cooling to 25–50℃, it was passedivated by purging with an O2 / Ar atmosphere (a mixture of oxygen and argon in a volume ratio of 5 / 95) for 1 hour to obtain MgAlO. x / Ni-1 reverse catalyst;

[0053] (5) The obtained MgAlO x In the application of the / Ni-1 reverse catalyst in the dry reforming of methane and carbon dioxide to produce syngas, the reaction conditions are as follows: the reaction is carried out in a fixed-bed reactor containing the catalyst, the catalyst dosage is 50 mg, the reaction pressure is 0.1 MPa, the reaction gas ratio is CH4:CO2:N2 = 2:2:1, the reaction gas flow rate is 50 mL / min, and the reaction temperature is 800 °C.

[0054] MgAlO in Example 2 x X-ray diffraction pattern of NiO-1 reverse catalyst ( Figure 4 ), HAADF-STEM image ( Figure 5 ) and Elements Mapping graph ( Figure 6 This indicates that MgAlO x A layer is uniformly coated on the surface of the Ni support, MgAlO x The average thickness of the nanolayers ranges from 1 to 5 nm, and the particle size of the Ni support ranges from 10 to 100 nm. DRM performance evaluation results show that ( Figure 7 After 60 hours of reaction, the conversion rate of CH4 decreased from 94.4% to 90.1%, indicating excellent stability.

[0055] Example 3

[0056] (1) Place 1.0g Ni powder and 1.5g Al(NO3)3·9H2O into an agate mortar and grind for 10 minutes;

[0057] (2) Transfer the resulting mixture to a 10 mL glass vial, add 1-2 drops of deionized water to the resulting powder, and then treat it in a vacuum oven at 90 °C for 48 hours.

[0058] (3) The mixture was heated to 800°C in a muffle furnace at a rate of 2°C / min and held at this temperature for 2 hours. The resulting product was labeled as AlO.x / NiO-2;

[0059] (4) AlO x The NiO-2 sample was heated to 650℃ at a rate of 5℃ / min in a pure H2 atmosphere (50 mL / min) and held for 2 hours. After cooling to 25–50℃, it was passedivated by purging with an O2 / Ar atmosphere (a mixture of oxygen and argon in a volume ratio of 5 / 95) for 1 hour to obtain AlO. x / Ni-2 reverse catalyst;

[0060] (5) The obtained AlO x In the application of the / Ni-2 reverse catalyst in the dry reforming of methane and carbon dioxide to produce syngas, the reaction conditions are as follows: the reaction is carried out in a fixed-bed reactor containing the catalyst, the catalyst dosage is 50 mg, the reaction pressure is 0.1 MPa, the reaction gas ratio is CH4:CO2:N2 = 2:2:1, the reaction gas flow rate is 50 mL / min, and the reaction temperature is 800℃.

[0061] AlO in Example 3 x The DRM performance evaluation results of the / NiO-2 reverse catalyst show that ( Figure 8 After 20 hours of reaction, the conversion rate of CH4 decreased from 94.3% to 89.0%, and the stability was good.

[0062] Example 4

[0063] (1) Place 1.0g Ni powder, 0.34g Mg(NO3)2·6H2O and 1.35g Al(NO3)3·9H2O into an agate mortar and grind for 10 minutes;

[0064] (2) Transfer the resulting mixture to a 10 mL glass vial, add 1-2 drops of deionized water to the resulting powder, and then treat it in a vacuum oven at 90 °C for 48 hours.

[0065] (3) The mixture was heated to 800°C in a muffle furnace at a rate of 2°C / min and held at this temperature for 2 hours. The resulting product was labeled as MgAlO. x / NiO-2;

[0066] (4) MgAlO x The NiO-2 sample was heated to 650℃ in a pure H2 atmosphere (50 mL / min) at a rate of 5℃ / min and held for 2 hours. After cooling to 25–50℃, it was passedivated by purging with an O2 / Ar atmosphere (a mixture of oxygen and argon in a volume ratio of 5 / 95) for 1 hour to obtain MgAlO. x / Ni-2 reverse catalyst;

[0067] (5) The obtained MgAlO x In the application of the / Ni-2 reverse catalyst in the dry reforming of methane and carbon dioxide to produce syngas, the reaction conditions are as follows: the reaction is carried out in a fixed-bed reactor containing the catalyst, the catalyst dosage is 50 mg, the reaction pressure is 0.1 MPa, the reaction gas ratio is CH4:CO2:N2 = 2:2:1, the reaction gas flow rate is 50 mL / min, and the reaction temperature is 800 °C.

[0068] MgAlO in Example 4 x The DRM performance evaluation results of the / NiO-2 reverse catalyst show that ( Figure 9 After 20 hours of reaction, the conversion rate of CH4 decreased from 93.2% to 89.7%, indicating good stability.

[0069] Comparative Example 1

[0070] (1) Disperse 1.0g Al2O3 powder in 20mL deionized water, add 1.2g Ni(NO3)2·6H2O, and stir for 10 minutes;

[0071] (2) The resulting mixture was heated to 60°C to evaporate the solvent, and then dried in an oven at 60°C for 24 hours;

[0072] (3) Grind the dried precursor thoroughly, heat it to 800°C in a muffle furnace at a rate of 2°C / min, and calcine it for 2 hours;

[0073] (4) The sample was heated to 650°C at a rate of 5°C / min in a pure H2 atmosphere and reduced for 2 hours. The resulting sample was labeled as Ni / Al2O3.

[0074] (5) The Ni / Al2O3 catalyst obtained was used in the dry reforming of methane and carbon dioxide to prepare syngas. The reaction conditions were as follows: the reaction was carried out in a fixed-bed reactor containing the catalyst, the amount of catalyst was 50 mg, the reaction pressure was 0.1 MPa, the ratio of reaction gas was CH4:CO2:N2=2:2:1, the reaction gas flow rate was 50 mL / min, and the reaction temperature was 800 °C.

[0075] The DRM performance evaluation results of the Ni / Al2O3 catalyst in Comparative Example 1 show that ( Figure 10 After 60 hours of reaction, the conversion rate of CH4 decreased from 87.0% to less than 2.0%, indicating complete inactivation.

[0076] Comparative Example 2

[0077] (1) Disperse 1.0g of MgAl2O4 powder in 20mL of deionized water, add 1.2g of Ni(NO3)2·6H2O, and stir for 10 minutes;

[0078] (2) The resulting mixture was heated to 60°C to evaporate the solvent, and then dried in an oven at 60°C for 24 hours;

[0079] (3) Grind the dried precursor thoroughly, heat it to 800°C in a muffle furnace at a rate of 2°C / min, and calcine it for 2 hours;

[0080] (4) The sample was heated to 650°C at a rate of 5°C / min in a pure H2 atmosphere and reduced for 2 hours. The resulting sample was labeled as Ni / MgAl2O4;

[0081] (5) The Ni / Al2O3 catalyst obtained was used in the dry reforming of methane and carbon dioxide to prepare syngas. The reaction conditions were as follows: the reaction was carried out in a fixed-bed reactor containing the catalyst, the amount of catalyst was 50 mg, the reaction pressure was 0.1 MPa, the ratio of reaction gas was CH4:CO2:N2=2:2:1, the reaction gas flow rate was 50 mL / min, and the reaction temperature was 800 °C.

[0082] The DRM performance evaluation results of the MgAl2O4 catalyst in Comparative Example 2 show that ( Figure 10 After 50 hours of reaction, the conversion rate of CH4 decreased from 90.9% to 58.8%, indicating severe inactivation.

[0083] This invention successfully constructed an oxide / nickel inversion catalyst, which consists of an oxide nanostructure (such as AlO) modified on its surface. x and MgAlO x The bulk nickel composition (such as metallic nickel powder and nickel oxide powder) is used in the DRM reaction. It is conducted at high temperature (800℃), high reactant concentrations (40% CH4 and 40% CO2), and high space velocity (79,000 mL·g⁻¹). -1 ·h -1 Under these conditions, AlO x The Ni-1 reverse catalyst maintained an 83.1% CH4 conversion after more than 60 hours of operation, while the Ni / Al2O3 catalyst was completely deactivated after 60 hours. The optimized MgAlO... x The Oxide / Ni-1 reverse catalyst maintained a 70% CH4 conversion rate after more than 260 hours of operation, while the Ni / MgAl2O4 catalyst rapidly deactivated after 50 hours. These results demonstrate the significant advantages of the Oxide / Ni reverse catalyst in the DRM reaction, providing crucial technical support for the industrial application of DRM.

[0084] In summary, the reverse catalyst of this invention exhibits high conversion rates of methane and carbon dioxide and excellent catalytic stability in the high-temperature, atmospheric-pressure dry reforming of methane and carbon dioxide to syngas. Furthermore, the preparation method of this invention is simple, uses inexpensive raw materials, and is highly versatile, possessing enormous potential for industrial application.

[0085] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the implementation. The scope of protection of the present invention should be determined by the scope defined in the claims. Other variations or modifications can be made based on the above description. Obvious variations or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A method for preparing a supported Oxide / Ni reverse catalyst, comprising the following steps: (1) Mix the precursor of the metal oxide with bulk nickel in a certain proportion and grind them evenly. Add 1 to 2 drops of deionized water to the resulting powder. (2) The mixed powder obtained in step (1) is vacuum dried for 24 to 72 hours to obtain a mixed powder precursor; (3) The mixed powder precursor obtained in step (2) is calcined in air at 500-1000℃ for 1-3 hours to obtain Oxide / NiO sample; (4) The Oxide / NiO sample obtained in step (3) is reduced in a hydrogen atmosphere at 550-750℃ for 1-3 hours. After cooling to 25-50℃, it is purged in an O2 / Ar atmosphere for 0.5-2 hours for passivation treatment to obtain the Oxide / Ni reverse catalyst.

2. The preparation method according to claim 1, characterized in that, The precursor of the metal oxide in step (1) is at least one of magnesium, aluminum nitrate, chlorate, acetate, sulfate, and organic salt; the metal oxide accounts for 0.5 wt% to 50 wt% of the total mass of the catalyst, preferably 1 wt% to 30 wt%.

3. The preparation method according to claim 1, characterized in that, The metal oxide mentioned in step (1) is an oxide of magnesium and aluminum, with a mass ratio of magnesium to aluminum of 1:5 to 5:1; the bulk nickel is at least one of nickel metal powder and nickel oxide powder.

4. The preparation method according to claim 1, characterized in that, The temperature of vacuum drying in step (2) is controlled at 60-90℃; the temperature of calcination in step (3) is 750-850℃, and the heating rate is 1-5℃ / min.

5. The preparation method according to claim 1, characterized in that, The reduction treatment in step (4) is performed at a temperature of 600-700℃, a heating rate of 2-10℃ / min, and an H2 flow rate of 20-100ml / min; the O2 / Ar atmosphere is a mixture of oxygen and argon in a volume ratio of 1:99-10:

90.

6. The supported Oxide / Ni inverted catalyst prepared by the preparation method according to any one of claims 1-5.

7. The supported Oxide / Ni reverse catalyst according to claim 6, characterized in that, The catalyst comprises an oxide and a bulk Ni support. The oxide exists in the form of nanoparticles and nanofilms. The particle size of the bulk Ni support is 10–1000 nm. The particle size of the oxide nanoparticles is 3–50 nm, and the thickness of the oxide nanofilm is 1–10 nm.

8. The application of the supported Oxide / Ni reverse catalyst according to claim 6 or 7 in the dry reforming of methane and carbon dioxide to produce syngas.

9. The application according to claim 8, characterized in that, The methane-carbon dioxide dry reforming to produce syngas is carried out in a fixed bed or a moving bed.

10. The application according to claim 8, characterized in that, The reaction conditions for the preparation of syngas by dry reforming methane with carbon dioxide are as follows: reaction pressure 0.01–1 MPa, reaction gas ratio CH4:CO2:N2 = 1–3:3–1:1, and reaction gas flow rate 10,000–80,000 mL·g. -1 ·h -1 The reaction temperature is 750–850℃.

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