Method for preparing low-carbon olefin by dehydrogenation of low-carbon alkane through catalytic oxidation of nitrogen oxide

Abstract

The invention relates to a method for preparing low-carbon olefin by dehydrogenation of low-carbon alkane through catalytic oxidation of nitrogen oxide, and belongs to the technical field of chemical production. According to the method, low-carbon alkane and nitrogen oxide NOx are subjected to one-step reaction in a reactor filled with a catalyst to generate low-carbon olefin and simultaneously generate ammonia gas, and byproducts comprise carbon monoxide, carbon dioxide, water and nitrogen. The method has the advantages of short process flow, simplicity in operation and easiness in industrial amplification, and the air pollutant NOx can be recycled. The reaction is higher in oxygen-free catalytic dehydrogenation conversion rate of low-carbon alkane, and carbon deposition is not easy to occur; compared with oxygen oxidation low-carbon alkane dehydrogenation products, the olefin selectivity is high, and the danger coefficient is low. In addition, the method also has an effect on other alkanes except ethane and propane, so that the application range can be expanded.

Description

Technical Field

[0001] The present invention relates to a method for catalytic oxidation of nitrogen oxides to dehydrogenate lower alkanes to prepare lower olefins, belonging to the technical field of chemical production. Background Art

[0002] Lower olefins are important industrial raw materials and products in petrochemical industry. Ethylene is the raw material for producing chemicals such as polyethylene, acetaldehyde, acetic acid, propionaldehyde, and propionic acid. Propylene is the raw material for producing important chemicals such as polypropylene, acrylonitrile, propylene oxide, and acrylic acid. In recent years, the demand for lower olefins has been increasing day by day, and the market supply can no longer meet the demand, and the supply-demand gap is continuously growing. Therefore, it is very meaningful to develop a new reaction path for preparing lower olefins from lower alkanes.

[0003] At present, ethylene is mainly produced industrially by steam cracking of naphtha and ethane. Catalytic cracking, alkane dehydrogenation, and methanol-to-olefins technologies are also constantly developing. Shale gas contains 80-90% methane and 1-14% ethane. The discovery of shale gas has also enriched the raw material sources for producing ethylene. Although the steam cracking of naphtha and ethane to produce ethylene has been industrialized, the steam cracking of naphtha requires a high temperature of 1000 °C, and the steam cracking of ethane also requires a high temperature of 600-800 °C, with high energy consumption, high requirements for equipment, and the catalyst is prone to carbon deposition. Industrial production of propylene mainly adopts naphtha cracking and propane catalytic cracking methods. Coal or natural gas-based syngas routes have also developed in recent years, such as Fischer-Tropsch synthesis and methanol-to-propylene technology. Although the above processes have been industrialized, they still have the disadvantages of high reaction temperature, high energy consumption, high equipment requirements, and easy carbon deposition. Therefore, the development of ethane and propane dehydrogenation processes can avoid the disadvantages of high temperature, easy carbon deposition, and complex product composition of naphtha and steam cracking processes. Lower alkane dehydrogenation includes direct dehydrogenation and catalytic dehydrogenation. Direct dehydrogenation is an endothermic reaction that is thermodynamically unfavorable (see reaction equations (1)-(2)) and requires a relatively high temperature, while oxidative dehydrogenation is an exothermic reaction that is thermodynamically favorable (see reaction equations (3)-(4)) and can be carried out at a low temperature. The commonly used oxidant for oxidative dehydrogenation is oxygen. However, as a relatively strong oxidant, oxygen is very likely to deeply oxidize lower alkanes to carbon dioxide (see reaction equations (5)-(6)), thereby reducing the olefin selectivity.

[0004] C3H8(g) = H2(g) + C3H6(g) ΔH(300K) = 50.47 kJ / mol (1)

[0005] C2H6(g) = H2(g) + C2H4(g) ΔH(300K) = 65.39 kJ / mol (2)

[0006] 2C2H6(g) + O2(g) = 2C2H4(g) + 2H2O(g) ΔH(300K) = -300.02 kJ / mol (3)

[0007] 2C3H8(g) + O2(g) = 2C3H6(g) + 2H2O(g) ΔH(300K) = -329.84 kJ / mol (4)

[0008] C3H8(g) + 5O2(g) = 3CO2(g) + 4H2O(g) ΔH(300K) = -2102.64 kJ / mol (5)

[0009] C2H6(g) + 3.5O2(g) = 2CO2(g) + 3H2O(g) ΔH(300K) = -1456.96 kJ / mol(6)

[0010] Therefore, developing a new weak oxidant to oxidize these light alkanes for dehydrogenation can improve the selectivity of propylene. Compared with the direct catalytic dehydrogenation of light alkanes, it can also reduce the reaction temperature and inhibit carbon deposition. Nitrogen oxides (NO x ) are atmospheric pollutants emitted from factories and vehicle exhausts. They can react with water and oxygen in the air to form nitric acid, which is one of the main substances causing acid rain and will seriously damage the environmental quality. Currently in industry, NO x is mainly removed as a pollutant by reacting with reducing gases such as ammonia and hydrocarbons to form nitrogen. The oxidizing property of NO x is weaker than that of oxygen. In view of this, we invented a new reaction and process using light alkanes to react with NO x to produce light olefins and ammonia, enabling NO x to be reused, as shown in reaction equations (7)-(14).

[0011] 2.5C2H6(g) + NO(g) = NH3(g) + H2O(g) + 2.5C2H4(g) ΔH(300K) = -122.33kJ / mol (7)

[0012] 3.5C2H6(g) + NO2(g) = NH3(g) + 2H2O(g) + 3.5C2H4(g) ΔH(300K) = -257.53 kJ / mol (8)

[0013] 6C2H6(g) + N2O3(g) = 2NH3(g) + 3H2O(g) + 6C2H4(g) ΔH(300K) = -420.31kJ / mol (9)

[0014] 4C2H6(g) + N2O(g) = 2NH3(g) + H2O(g) + 4C2H4(g) ΔH(300K) = -52.65 kJ / mol (10)

[0015] 2.5C3H8(g) + NO(g) = NH3(g) + H2O(g) + 2.5C3H6(g) ΔH(300K) = -159.61 kJ / mol (11)

[0016] 3.5C3H8(g) + NO2(g) = NH3(g) + 2H2O(g) + 3.5C3H6(g) ΔH(300K) = -309.73 kJ / mol (12)

[0017] 6C3H8(g) + N2O3(g) = 2NH3(g) + 3H2O(g) + 6C3H6(g) ΔH(300K) = -509.79 kJ / mol (13)

[0018] 4C3H8(g) + N2O(g) = 2NH3(g) + H2O(g) + 4C3H6(g) ΔH(300K) = -112.30 kJ / mol (14)

[0019] Using NO x The catalytic oxidation of light alkanes for dehydrogenation has the advantage of preventing deep oxidation compared to the direct oxidation of light alkanes with oxygen, and is thermodynamically favorable and has a lower reaction temperature compared to the catalytic dehydrogenation of light alkanes. At the same time, the air pollutant NO x can be reused, which has significance for industrial applications and basic research. Summary of the Invention

[0020] The object of the present invention is to provide a method for preparing light olefins by catalytic oxidation of light alkanes with nitrogen oxides.

[0021] To achieve the above object, the present invention adopts the following technical solutions:

[0022] A method for preparing light olefins by catalytic oxidation of light alkanes with nitrogen oxides, where light alkanes and nitrogen oxides NO x react in one step through a reactor equipped with a catalyst to generate light olefins and ammonia simultaneously, and the by-products include carbon monoxide, carbon dioxide, water, and nitrogen.

[0023] In the above technical solution, further, the reactor is a fixed-bed reactor, and the reactor is a single reactor or a group of two or more reactors.

[0024] In the above technical solution, further, the low-carbon alkane is a low-boiling alkane containing carbon, and is selected from any one of ethane, propane, n-butane, isobutane, n-pentane, isopentane, and neopentane.

[0025] In the above technical solution, further, the flow rate of the low-carbon alkane in the reactor is 10-400 mL / min, preferably 10-40 mL / min.

[0026] In the above technical solution, further, the nitrogen oxides are selected from any one of nitric oxide, nitrogen dioxide, dinitrogen oxide, and dinitrogen trioxide, and preferably nitric oxide.

[0027] In the above technical solution, further, the flow rate of the nitrogen oxides in the reactor is 10-400 mL / min, preferably 10-40 mL / min.

[0028] In the above technical solution, further, the balance gas in the reactor is any one of argon and helium, and preferably argon.

[0029] In the above technical solution, further, the flow rate of the balance gas in the reactor is 10-400 mL / min, preferably 40-70 mL / min.

[0030] In the above technical solution, further, the heating rate of the heating zone where the reaction occurs is 2-20 °C / min, preferably 10 °C / min; the reaction temperature is 300-1000 °C, preferably 500-900 °C; the reaction pressure is 0.01-5 MPa, preferably 0.1-0.5 MPa.

[0031] In the above technical solution, further, the catalyst is any one of nickel-based, platinum-based, iron-based, chromium-based, cobalt-based, and molybdenum-based, and preferably platinum-based and iron-based.

[0032] In the above technical solution, further, the catalyst loading is 0.1-10 wt%, preferably 0.1-2 wt%.

[0033] In the above technical solution, further, the mesh number of the catalyst is 4-400 meshes, preferably 20-40 meshes.

[0034] Before the reaction of the present invention, it is heated to the reaction temperature under a pretreatment atmosphere and then switched to the raw material gas for reaction. The gas after the reaction is analyzed online by combining the thermal conductivity detector and the hydrogen flame ionization detector of a gas chromatograph.

[0035] The gas in the pretreatment atmosphere is hydrogen, argon, helium, etc.

[0036] The beneficial effects of the present invention are as follows:

[0037] Compared with the prior art, the beneficial effects of the nitrogen oxide-catalyzed oxidation of lower alkanes for dehydrogenation to produce lower olefins provided by the present invention are mainly reflected in the following aspects:

[0038] (1) Using NO x to catalytically oxidize lower alkanes for dehydrogenation to produce lower olefins and simultaneously co-produce ammonia, enabling the reuse of the air pollutant NO x Moreover, due to the moderate oxidizing property of NO x the conversion rate of lower alkanes and the selectivity of the product olefins can be increased;

[0039] (2) NO x can react with carbon deposition to inhibit carbon deposition and improve the catalyst life;

[0040] (3) Further cost reduction and industrial scale-up can be achieved through a dual-reactor or multi-reactor process;

[0041] In summary, the process of the nitrogen oxide-catalyzed oxidation of lower alkanes for dehydrogenation to produce lower olefins provided by the present invention is simple, green and environmentally friendly, and has good industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a process flow diagram of the nitrogen oxide-catalyzed oxidation of lower alkanes for dehydrogenation to produce lower olefins according to the present invention;

[0043] Figure 2 is a graph of propane conversion rate and carbon-based product selectivity;

[0044] Figure 3 is a graph of nitric oxide conversion rate and nitrogen-based product selectivity. DETAILED DESCRIPTION OF THE INVENTION

[0045] The following is a detailed description of the whole process through examples, but the scope of the claims of the present invention is not limited by these examples.

[0046] Example 1

[0047] The device used is a fixed-bed reactor with a quartz reaction tube having an inner diameter of 10 mm; a Pt-Sn catalyst supported on MFI zeolite with a particle size of 20-40 mesh, a Pt loading of 1-6 wt%, and a Sn loading of 0-9 wt% is placed in the isothermal section of the reaction tube; under a hydrogen atmosphere of 40 mL / min, the reactor temperature is raised from room temperature to 600 °C over 120 min, the pressure is kept constant at 0.1 MPa, and after pretreatment for 60 min under these conditions, it is switched to a mixed gas with a propane concentration of 20%, a nitric oxide concentration of 20%, and argon as the balance gas, maintaining a flow rate of 100 mL / min, with the temperature and pressure unchanged; sampling and analysis start after 60 min; the amount of ammonia absorbed is detected using cation chromatography, the gas-phase products are detected using gas chromatography, and the propane and nitric oxide conversion rates and the propylene and ammonia selectivities are shown in Table 1.

[0048] Example 2

[0049] The device used is a fixed-bed reactor with a quartz reaction tube having an inner diameter of 10 mm; a Pt-Sn catalyst supported on MFI zeolite with a particle size of 20-40 mesh, a Pt loading of 1-6 wt%, and a Sn loading of 0-9 wt% is placed in the isothermal section of the reaction tube; under a hydrogen atmosphere of 40 mL / min, the reactor temperature is raised from room temperature to 500 °C over 120 min, the pressure is kept constant at 0.1 MPa, and after pretreatment for 60 min under these conditions, it is switched to a mixed gas with a propane concentration of 40%, a nitrous oxide concentration of 10%, and argon as the balance gas, maintaining a flow rate of 100 mL / min, with the temperature and pressure unchanged; sampling and analysis start after 60 min; the amount of ammonia absorbed is detected using cation chromatography, the gas-phase products are detected using gas chromatography, and the propane and nitrous oxide conversion rates and the propylene and ammonia selectivities are shown in Table 2.

[0050] Example 3

[0051] The device used is a fixed-bed reactor with a quartz reaction tube having an inner diameter of 10 mm; a Pt-Sn catalyst supported on MFI zeolite with a particle size of 20-40 mesh, a Pt loading of 1-6 wt%, and a Sn loading of 0-9 wt% is placed in the isothermal section of the reaction tube; under a hydrogen atmosphere of 40 mL / min, the reactor temperature is raised from room temperature to 550 °C over 120 min, the pressure is kept constant at 0.5 MPa, and after pretreatment for 60 min under these conditions, it is switched to a mixed gas with a propane concentration of 10%, a nitrogen dioxide concentration of 40%, and argon as the balance gas, maintaining a flow rate of 100 mL / min, with the temperature and pressure unchanged; sampling and analysis start after 60 min; the amount of ammonia absorbed is detected using cation chromatography, the gas-phase products are detected using gas chromatography, and the propane and nitrogen dioxide conversion rates and the propylene and ammonia selectivities are shown in Table 3.

[0052] Example 4

[0053] The device used is a fixed-bed reactor with a quartz reaction tube having an inner diameter of 10 mm; a Pt-Sn catalyst supported on MFI zeolite with a particle size of 20-40 mesh, a Pt loading of 1-6 wt%, and a Sn loading of 0-9 wt% is placed in the isothermal section of the reaction tube; under a hydrogen atmosphere of 40 mL / min, the reactor temperature is raised from room temperature to 700 °C over 140 min, and the pressure is kept constant at 0.1 MPa. After pretreatment under these conditions for 60 min, it is switched to a mixed gas with an ethane concentration of 20%, a nitric oxide concentration of 20%, and argon as the balance gas, maintaining a flow rate of 100 mL / min, and the temperature and pressure remain unchanged; sampling and analysis start after 60 min; a cation chromatography is used to detect the amount of ammonia absorbed, and a gas chromatography is used to detect the gas-phase products. The ethane and nitric oxide conversion rates and the propylene and ammonia selectivities are shown in Table 4.

[0054] Example 5

[0055] The device used is a fixed-bed reactor with a quartz reaction tube having an inner diameter of 10 mm; a Pt-Sn catalyst supported on MFI zeolite with a particle size of 20-40 mesh, a Pt loading of 1-6 wt%, and a Sn loading of 0-9 wt% is placed in the isothermal section of the reaction tube; under a hydrogen atmosphere of 40 mL / min, the reactor temperature is raised from room temperature to 800 °C over 140 min, and the pressure is kept constant at 0.1 MPa. After pretreatment under these conditions for 60 min, it is switched to a mixed gas with an ethane concentration of 40%, a nitrous oxide concentration of 10%, and argon as the balance gas, maintaining a flow rate of 100 mL / min, and the temperature and pressure remain unchanged; sampling and analysis start after 60 min; a cation chromatography is used to detect the amount of ammonia absorbed, and a gas chromatography is used to detect the gas-phase products. The ethane and nitrous oxide conversion rates and the ethylene and ammonia selectivities are shown in Table 5.

[0056] Example 6

[0057] The device used is a fixed-bed reactor with a quartz reaction tube having an inner diameter of 10 mm; a Pt-Sn catalyst supported on MFI zeolite with a particle size of 20-40 mesh, a Pt loading of 1-6 wt%, and a Sn loading of 0-9 wt% is placed in the isothermal section of the reaction tube; under a hydrogen atmosphere of 40 mL / min, the reactor temperature is raised from room temperature to 900 °C over 140 min, and the pressure is kept constant at 0.55 MPa. After pretreatment under these conditions for 60 min, it is switched to a mixed gas with an ethane concentration of 10%, a nitrogen dioxide concentration of 40%, and argon as the balance gas, maintaining a flow rate of 100 mL / min, and the temperature and pressure remain unchanged; sampling and analysis start after 60 min; a cation chromatography is used to detect the amount of ammonia absorbed, and a gas chromatography is used to detect the gas-phase products. The ethane and nitrogen dioxide conversion rates and the ethylene and ammonia selectivities are shown in Table 6.

[0058] The catalysts used in Examples 7-9 were prepared by the deposition-precipitation method. The specific process is as follows:

[0059] (1) Weigh a certain amount of nitrates of three metals according to the molar ratio of Fe:Co:Zn = 7:2:1 and dissolve them in deionized water;

[0060] (2) Drop ammonia water into it until pH = 8.5;

[0061] (3) Age in an oven at 70 °C for 2 h;

[0062] (4) Vacuum filter until pH = 7 and then place it in an oven at 80 °C to dry for 8 h;

[0063] (5) Bake in air at 600 / 650 / 700 / 800 °C for 8 h to obtain the Fe7Co2Zn1O x -X (X = 600 / 650 / 700 / 800 °C) catalyst.

[0064] Example 7

[0065] The device used is a fixed-bed reactor, and the reaction tube is a quartz tube with an inner diameter of 10 mm; place the Fe7Co2Zn1O x catalyst prepared at different calcination temperatures of 20 - 40 mesh in the isothermal section of the reaction tube; under an argon atmosphere of 40 mL / min, raise the reactor temperature from room temperature to 600 °C in 120 min, keep the pressure constant at 0.1 MPa, pre-treat for 60 min under this condition and then switch to a mixed gas with a propane concentration of 20%, a nitric oxide concentration of 20%, and argon as the balance gas, keep the flow rate at 100 mL / min, and keep the temperature and pressure unchanged; start sampling and analysis after 60 min; use cation chromatography to detect the amount of ammonia absorbed, use gas chromatography to detect the gas-phase products, and the propane and nitric oxide conversion rates and the propylene and ammonia selectivities are shown in Table 7.

[0066] Example 8

[0067] The device used is a fixed-bed reactor, and the reaction tube is a quartz tube with an inner diameter of 10 mm; place the Fe7Co2Zn1O x catalyst prepared at different calcination temperatures of 20 - 40 mesh in the isothermal section of the reaction tube; under an argon atmosphere of 40 mL / min, raise the reactor temperature from room temperature to 500 °C in 120 min, keep the pressure constant at 0.1 MPa, pre-treat for 60 min under this condition and then switch to a mixed gas with a propane concentration of 40%, a nitrous oxide concentration of 20%, and argon as the balance gas, keep the flow rate at 100 mL / min, and keep the temperature and pressure unchanged; start sampling and analysis after 60 min; use cation chromatography to detect the amount of ammonia absorbed, use gas chromatography to detect the gas-phase products, and the propane and nitrous oxide conversion rates and the propylene and ammonia selectivities are shown in Table 8.

[0068] Example 9

[0069] The device used is a fixed-bed reactor, and the reaction tube is a quartz tube with an inner diameter of 10 mm; Fe7Co2Zn1O catalysts prepared at different calcination temperatures of 20-40 mesh are placed in the isothermal section of the reaction tube. x Under an argon atmosphere of 40 mL / min, the temperature of the reactor is raised from room temperature to 550 °C over 120 min, the pressure is kept constant at 0.5 MPa, and after pretreatment for 60 min under these conditions, it is switched to a mixed gas with a propane concentration of 10%, a nitrogen dioxide concentration of 20%, and argon as the balance gas, maintaining a flow rate of 100 mL / min, with the temperature and pressure unchanged; Sampling and analysis start after 60 min; The amount of ammonia absorbed is detected using cation chromatography, and the gas-phase products are detected using gas chromatography. The propane and nitrogen dioxide conversion rates and the propylene and ammonia selectivities are shown in Table 9.

[0070] As Figure 2 shown, the PtSn / MFI catalyst has a relatively high propane conversion rate and propylene selectivity; As the Sn content increases, the propane conversion rate gradually increases, and the propylene selectivity remains basically unchanged.

[0071] As Figure 3 shown, the PtSn / MFI catalyst has a relatively high nitrogen dioxide conversion rate and ammonia selectivity; As the Sn content increases, the nitrogen dioxide conversion rate remains basically unchanged, and the ammonia selectivity gradually increases.

[0072] Table 1: Conversion rate - selectivity of catalytic oxidation of nitrogen oxides and dehydrogenation of light alkanes to prepare light olefins in Example 1

[0073]

[0074] Table 2: Conversion rate - selectivity of catalytic oxidation of nitrogen oxides and dehydrogenation of light alkanes to prepare light olefins in Example 2

[0075]

[0076] Table 3: Conversion rate - selectivity of catalytic oxidation of nitrogen oxides and dehydrogenation of light alkanes to prepare light olefins in Example 3

[0077]

[0078] Table 4: Conversion rate - selectivity of catalytic oxidation of nitrogen oxides and dehydrogenation of light alkanes to prepare light olefins in Example 4

[0079]

[0080]

[0081] Table 5: Conversion rate - selectivity of catalytic oxidation of nitrogen oxides and dehydrogenation of light alkanes to prepare light olefins in Example 5

[0082]

[0083] Table 6: Conversion - Selectivity of Catalytic Oxidation of Low - Carbon Alkanes with Nitrogen Oxides for the Dehydrogenation to Produce Low - Carbon Olefins in Example 6

[0084]

[0085]

[0086] Table 7: Conversion - Selectivity of Catalytic Oxidation of Low - Carbon Alkanes with Nitrogen Oxides for the Dehydrogenation to Produce Low - Carbon Olefins in Example 7

[0087]

[0088] Table 8: Conversion - Selectivity of Catalytic Oxidation of Low - Carbon Alkanes with Nitrogen Oxides for the Dehydrogenation to Produce Low - Carbon Olefins in Example 8

[0089]

[0090] Table 9: Conversion - Selectivity of Catalytic Oxidation of Low - Carbon Alkanes with Nitrogen Oxides for the Dehydrogenation to Produce Low - Carbon Olefins in Example 9

[0091]

[0092] The embodiments of the present invention have been described above. However, the present invention is not limited to the above - described embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for catalytic oxidation of nitrogen oxides to dehydrogenate low-carbon alkanes to prepare low-carbon olefins, characterized in that, Low-carbon alkanes and nitrogen oxides NO x React in one step through a reactor filled with a catalyst to produce low-carbon olefins and ammonia simultaneously, with by-products including carbon monoxide, carbon dioxide, water, and nitrogen.

2. The method for catalytic oxidation of nitrogen oxides to dehydrogenate lower alkanes to prepare lower olefins according to claim 1, wherein The reactor is a fixed-bed reactor, which can be a single reactor or a group of two or more reactors.

3. A method for catalytic oxidation of nitrogen oxides to dehydrogenate lower alkanes to prepare lower olefins according to claim 1, characterized in that, The low-carbon alkane is a low-boiling alkane containing carbon, selected from any one of ethane, propane, n-butane, isobutane, n-pentane, isopentane, and neopentane; the flow rate of the low-carbon alkane in the reactor is 10-400 mL / min.

4. A method for catalytic oxidation of nitrogen oxides to dehydrogenate lower alkanes to prepare lower olefins according to claim 1, characterized in that, The nitrogen oxide is selected from any one of nitric oxide, nitrogen dioxide, dinitrogen oxide, and dinitrogen trioxide; the flow rate of the nitrogen oxide in the reactor is 10-400 mL / min.

5. A method for catalytic oxidation of nitrogen oxides and dehydrogenation of lower alkanes to prepare lower olefins according to claim 1, characterized in that, The balance gas in the reactor is any one of argon and helium; the flow rate of the balance gas in the reactor is 10-400 mL / min.

6. The method for catalytic oxidation of nitrogen oxides to dehydrogenate lower alkanes to prepare lower olefins according to claim 1, wherein The heating rate of the heating zone where the reaction occurs is 2-20 °C / min; the reaction temperature is 300-1000 °C; the reaction pressure is 0.01-5 MPa.

7. A method for catalytic oxidation of nitrogen oxides and dehydrogenation of lower alkanes to prepare lower olefins according to claim 1, characterized in that The catalyst is any one of nickel-based, platinum-based, iron-based, chromium-based, cobalt-based, and molybdenum-based.

8. A method for catalytic oxidation of nitrogen oxides and dehydrogenation of lower alkanes to prepare lower olefins according to claim 1, characterized in that, The catalyst loading is 0.1-10 wt%; the mesh number of the catalyst is 4-400 mesh.

9. A method for catalytic oxidation of nitrogen oxides to dehydrogenate lower alkanes to prepare lower olefins according to claim 1, characterized in that, Before the reaction, it is heated to the reaction temperature under a pretreatment atmosphere and then switched to the raw material gas for reaction. The gas after the reaction is analyzed online by combining the thermal conductivity detector and the hydrogen flame ionization detector of a gas chromatograph.

10. The method for catalytic oxidation of nitrogen oxides to dehydrogenate lower alkanes to prepare lower olefins according to claim 9, wherein The gas in the pretreatment atmosphere is hydrogen, argon, or helium.

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