In-situ catalytic conversion of low to medium grade shale oil or oil shale

Abstract

The application provides an in-situ catalytic conversion method of medium-low mature shale oil or oil shale, and the method comprises the following steps: mixing shale and copper oxide nanosheet catalyst, and then carrying out a pyrolysis reaction under a closed condition under nitrogen and / or inert gas; and collecting pyrolysis products after the reaction is completed. The method provided by the application adopts a copper oxide catalyst system with a nanosheet structure, the catalyst has exposed abundant active sites and catalytic activity, the contact degree with the shale is high, the closed pyrolysis reaction is matched, the in-situ pyrolysis conversion of the shale is realized, the oil and gas recovery rate of the shale is improved, and the light degree of the oil product is improved.

Description

Technical Field

[0001] This invention belongs to the field of oilfield development technology, specifically relating to an in-situ catalytic conversion method for medium- and low-maturity shale oil or oil shale. Background Technology

[0002] Medium- and low-maturity shale oil and oil shale in-situ conversion have high oil and gas recovery rates and are considered "most promising" oil and gas resources. However, a suitable extraction technology route has yet to be found for these resources. The low- and medium-maturity shale oil or oil shale contains insufficient amounts of petroleum hydrocarbons and has poor fluidity, making it impossible to extract using existing mature engineering technologies. Currently, in-situ conversion technology is a key development area both domestically and internationally. However, the process from heating to the start of production takes months or even years, resulting in a large time span, high energy consumption, and the prolonged exposure of pyrolysis products to high temperatures making them prone to secondary reactions, leading to the conversion of light oil into gas. Therefore, how to reduce energy consumption and improve the recovery rate of pyrolysis light oil is a critical technical challenge that urgently needs to be addressed.

[0003] Catalysts play an irreplaceable and crucial role in the petrochemical industry, particularly in crude oil catalytic cracking processes, with their application history dating back to the early 20th century. For the in-situ conversion and exploitation of unconventional oil and gas resources, especially medium- and low-maturity shale oil or oil shale, the introduction of in-situ catalytic cracking technology can significantly reduce the activation energy required for in-situ conversion of medium- and low-maturity shale oil or oil shale at the thermodynamic level; and at the kinetic level, it promotes the directional depolymerization of kerogen macromolecules, improving the efficiency of organic matter cracking, while simultaneously enabling precise control of the reaction pathway, greatly increasing oil and gas recovery rates and the selectivity of light oil products. Currently explored catalysts include various metal oxides or sulfides, minerals, porous or nanomaterials, etc. However, despite a large amount of research and reports on shale catalytic pyrolysis, existing catalytic systems still have significant limitations. The dispersion of the catalyst in shale and its accessibility to kerogen greatly hinder catalytic cracking efficiency and oil and gas recovery rates.

[0004] CN117358284A discloses a catalyst for reducing the oil production temperature of oil shale pyrolysis, its preparation method, and its application. This pyrolysis method uses *Chlorella vulgaris* as a catalyst carrier, loading zinc chloride as the active ingredient, and then mixing the catalyst with oil shale for pyrolysis to improve the pyrolysis efficiency of oil shale. CN118956441A discloses a catalytic pyrolysis method for small-particle oil shale, which involves coating the surface of oil shale powder with a catalyst, performing low-temperature drying, and then fluidized bed roasting to obtain oil shale oil products. Introducing in-situ catalytic pyrolysis technology can significantly reduce the activation energy required for oil shale conversion at the thermodynamic level and promote the directional cracking of kerogen macromolecules at the kinetic level, thereby improving oil and gas recovery rates. However, the application of existing catalyst systems still faces many technical bottlenecks, especially the poor dispersion of the catalyst in oil shale and insufficient contact with kerogen, which seriously affects the efficiency of the catalytic cracking reaction and the recovery of oil and gas.

[0005] Therefore, developing novel catalyst systems and pyrolysis methods, and optimizing shale pyrolysis, are key to improving the efficiency of pyrolysis technology. Summary of the Invention

[0006] The purpose of this invention is to provide an in-situ catalytic conversion method for medium- and low-maturity shale oil or oil shale, thereby improving the pyrolysis conversion efficiency of shale and increasing oil and gas recovery.

[0007] To achieve this objective, the present invention employs the following technical solution:

[0008] This invention provides an in-situ catalytic conversion method for medium- and low-maturity shale oil or oil shale, the in-situ catalytic conversion method comprising the following steps:

[0009] Shale was mixed with copper oxide nanosheet catalyst and then subjected to a closed pyrolysis reaction under nitrogen and / or inert gas. The pyrolysis products were collected after the reaction was completed.

[0010] The method provided by this invention employs a copper oxide catalyst system with a nanosheet structure. The catalyst has abundant exposed active sites and catalytic activity, and has a high degree of contact with shale. Combined with a closed pyrolysis reaction, it realizes the in-situ pyrolysis transformation of shale, improves the oil and gas recovery rate of shale, and enhances the lightness of oil products.

[0011] In this invention, "medium to low maturity" refers to shale with a vitrinite reflectance (Ro) ≤ 1.0%.

[0012] Preferably, the shale has a particle size ≤ 60 mesh, for example, it can be 60 mesh, 70 mesh, 80 mesh, 100 mesh, 120 mesh, 140 mesh, 180 mesh, 200 mesh or 300 mesh, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0013] Preferably, the shale is crushed and screened before mixing.

[0014] Preferably, the mixing process includes: first dispersing the copper oxide nanosheet catalyst in water, then mixing it with the shale, and then drying it.

[0015] Preferably, the dispersion method includes ultrasound.

[0016] Preferably, the amount of the copper oxide nanosheet catalyst is 0.1-5 wt% of the shale, for example, it can be 0.1 wt%, 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, or 5 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0017] Preferably, the inert gas includes helium and / or argon.

[0018] Preferably, the temperature of the pyrolysis reaction is 300-600℃, for example, it can be 300℃, 350℃, 400℃, 450℃, 500℃, 550℃ or 600℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0019] Preferably, the pressure of the pyrolysis reaction is 0.5-5 MPa, for example, it can be 0.5 MPa, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa, 3 MPa, 3.5 MPa, 4 MPa, 4.5 MPa or 5 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0020] Preferably, the pyrolysis reaction time is 2-4 hours, for example, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0021] Preferably, the thickness of the copper oxide nanosheet catalyst is 5-25 nm, for example, it can be 5 nm, 10 nm, 15 nm, 20 nm or 25 nm, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0022] Preferably, the nanosheet diameter of the copper oxide nanosheet catalyst is 100-300 nm, for example, it can be 100 nm, 130 nm, 150 nm, 180 nm, 200 nm, 220 nm, 250 nm, 280 nm or 300 nm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0023] Preferably, the preparation process of the copper oxide nanosheet catalyst includes: mixing a copper salt solution with an alkaline solution to carry out a precipitation reaction, separating the solid and liquid phases to obtain a precipitate, and calcining the precipitate to obtain the copper oxide nanosheet catalyst.

[0024] Preferably, the copper salt comprises copper trihydrate and copper nitrate.

[0025] Preferably, the concentration of the copper salt solution is 0.01-0.2 mol / L, for example, it can be 0.01 mol / L, 0.05 mol / L, 0.1 mol / L, 0.15 mol / L or 0.2 mol / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0026] Preferably, the alkali includes sodium hydroxide.

[0027] Preferably, the concentration of the alkaline solution is 1-5 mol / L, for example, it can be 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L or 5 mol / L, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0028] Preferably, the roasting temperature is 300-600℃, for example, it can be 300℃, 350℃, 400℃, 450℃, 500℃, 550℃ or 600℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0029] Preferably, the roasting time is 3-5 hours, for example, 3 hours, 3.5 hours, 4 hours, 4.5 hours or 5 hours, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The method provided by this invention employs a copper oxide catalyst system with a nanosheet structure. The catalyst has abundant exposed active sites and catalytic activity, and has a high degree of contact with shale. Combined with a closed pyrolysis reaction, it realizes the in-situ pyrolysis transformation of shale, improves the oil and gas recovery rate of shale, and enhances the lightness of oil products. Attached Figure Description

[0032] Figure 1 This is the X-ray diffraction pattern of the copper oxide nanosheet catalyst prepared in Example 1;

[0033] Figure 2 This is a scanning electron micrograph of the copper oxide nanosheet catalyst prepared in Example 1;

[0034] Figure 3This is a comparison chart of the recovery rates of the in-situ catalytic conversion method for medium- and low-maturity shale provided in Example 1 and Comparative Example 1;

[0035] Figure 4 This is a simulated distillation comparison diagram of the pyrolysis oil products of the in-situ catalytic conversion method for medium and low maturity shale provided in Example 1 and Comparative Example 1;

[0036] Figure 5 This is a composition diagram of the pyrolysis gas products of the in-situ catalytic conversion method for medium- and low-maturity shale provided in Example 1;

[0037] Figure 6 This is a comparison chart of thermogravimetric and micro-thermogravimetric analyses of shale from Example 1 and Comparative Example 1. Detailed Implementation

[0038] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0039] To clearly illustrate the technical solution of the present invention, in a specific embodiment, a shale sample from a certain region is subjected to in-situ pyrolysis and transformation, and its Ro value is measured to be 0.6%, indicating that it is a medium-to-low maturity shale.

[0040] Preparation Example 1

[0041] This preparation example provides a copper oxide nanosheet catalyst.

[0042] The copper oxide nanosheet catalyst has a nanosheet thickness of 5 nm and a nanosheet diameter of 150 nm.

[0043] The preparation method of the copper oxide nanosheet catalyst includes the following steps:

[0044] (1) Dissolve copper nitrate trihydrate in deionized water and stir to obtain a solution with a concentration of 0.1 mol / L. Add sodium hydroxide solution with a concentration of 2 mol / L to the solution and stir to carry out precipitation reaction. After filtration, washing and drying, the precipitate is obtained.

[0045] (2) The obtained precipitate was calcined at 500℃ for 4h to obtain copper oxide nanosheet catalyst.

[0046] The X-ray diffraction pattern of the copper oxide nanosheet catalyst is shown in Figure 1. It can be seen that the copper oxide nanosheet catalyst is a monoclinic crystal. The scanning electron micrograph is shown in Figure 1. Figure 2 As shown, its morphology is a thin, sheet-like structure.

[0047] Comparative Preparation Example 1

[0048] This comparative preparation example provides a zinc oxide nanosheet catalyst.

[0049] The preparation method of the zinc oxide nanosheet catalyst is the same as that of Preparation Example 1, except that copper nitrate trihydrate is replaced with zinc nitrate in equal molar amounts of copper and zinc.

[0050] Example 1

[0051] This embodiment provides an in-situ catalytic conversion method for medium-to-low maturity shale oil or oil shale, the in-situ catalytic conversion method comprising the following steps:

[0052] (1) The shale was crushed and sieved to obtain a powder sample with a particle size ≤60 mesh;

[0053] (2) 1.5g of copper oxide nanosheet catalyst was mixed with water and ultrasonically dispersed. 30g of shale powder sample was impregnated with the copper oxide nanosheet catalyst at 5wt% of the shale powder. The mixture was then dried to obtain the final product.

[0054] (3) Place the obtained mixture in a sealed high-pressure reactor, introduce nitrogen into the reactor for 5 minutes to replace the air, then introduce 2 MPa of nitrogen and react at 450°C for 3 hours.

[0055] (4) After the reaction is complete, collect the oil and gas products.

[0056] In this embodiment, the copper oxide nanosheet catalyst is the copper oxide nanosheet catalyst provided in Preparation Example 1.

[0057] In this embodiment, the pyrolysis oil and gas recovery rate was calculated to be 8.75% based on the collected pyrolysis oil and gas products. Figure 3 As shown, the pyrolysis oil recovery rate is 0.45%, and the pyrolysis gas recovery rate is 8.3%.

[0058] The obtained pyrolysis oil products were analyzed by simulated distillation chromatography, such as... Figure 4 As shown, the distillation range of the pyrolysis oil is obtained: gasoline (C5-C5). 12 32.6%, diesel (C 12 -C 22 35.6%, lubricating oil (C 22 -C 30 24.1%, heavy oil (C 30 above) 7.7%.

[0059] The obtained pyrolysis gas products were analyzed by gas chromatography to determine the gas composition and content, such as... Figure 5 As shown: hydrogen 21.62%, carbon dioxide 13.59%, methane 53.96%, dienes 0.13%, ethane and propane 10.58%, C4 components 0.12%. It can be seen that the pyrolysis gas products are mainly composed of low-carbon alkanes.

[0060] Example 2

[0061] This embodiment provides an in-situ catalytic conversion method for medium-to-low maturity shale oil or oil shale, the in-situ catalytic conversion method comprising the following steps:

[0062] (1) The shale was crushed and sieved to obtain a powder sample with a particle size ≤60 mesh;

[0063] (2) The copper oxide nanosheet catalyst was mixed with water and ultrasonically dispersed to impregnate the shale powder sample. The amount of copper oxide nanosheet catalyst was 3 wt% of the shale. The mixture was then dried to obtain a mixture.

[0064] (3) Place the obtained mixture in a sealed high-pressure reactor, introduce nitrogen into the reactor for 5 minutes to replace the air, then introduce 0.5 MPa of nitrogen and react at 600°C for 3 hours.

[0065] (4) After the reaction is complete, collect the oil and gas products.

[0066] In this embodiment, the copper oxide nanosheet catalyst is the copper oxide nanosheet catalyst provided in Preparation Example 1.

[0067] In this embodiment, the pyrolysis oil and gas recovery rate was calculated to be 9.45% based on the collected pyrolysis oil and gas products, of which the pyrolysis oil recovery rate was 0.42% and the pyrolysis gas recovery rate was 9.03%.

[0068] The obtained pyrolysis oil products were analyzed by simulated distillation chromatography to obtain the distillation range of the pyrolysis oil: gasoline (C5-C5). 12 32.7%, diesel (C 12 -C 22 35.7%, lubricating oil (C 22 -C 30 23.3%, heavy oil (C 30 above) 8.3%.

[0069] The obtained pyrolysis gas products were analyzed by gas chromatography to determine the gas composition and content: hydrogen 22.05%, carbon dioxide 14.98%, methane 55.03%, dienes 0.11%, ethane and propane 7.89%, and C4 components 0.09%.

[0070] Example 3

[0071] This embodiment provides an in-situ catalytic conversion method for medium-to-low maturity shale oil or oil shale, the in-situ catalytic conversion method comprising the following steps:

[0072] (1) The shale was crushed and sieved to obtain a powder sample with a particle size ≤60 mesh;

[0073] (2) The copper oxide nanosheet catalyst was mixed with water and ultrasonically dispersed to impregnate the shale powder sample. The amount of copper oxide nanosheet catalyst was 0.1 wt% of the shale. The mixture was then dried to obtain a mixture.

[0074] (3) Place the obtained mixture in a sealed high-pressure reactor, introduce nitrogen into the reactor for 5 minutes to replace the air, then introduce 5 MPa of nitrogen and react at 300°C for 3 hours.

[0075] (4) After the reaction is complete, collect the oil and gas products.

[0076] In this embodiment, the copper oxide nanosheet catalyst is the copper oxide nanosheet catalyst provided in Preparation Example 1.

[0077] In this embodiment, the pyrolysis oil and gas recovery rate was calculated to be 2.28% based on the collected pyrolysis oil and gas products, of which the pyrolysis oil recovery rate was 0.10% and the pyrolysis gas recovery rate was 2.18%.

[0078] The obtained pyrolysis oil products were analyzed by simulated distillation chromatography to obtain the distillation range of the pyrolysis oil: gasoline (C5-C5). 12 33.3%, diesel (C 12 -C 22 35.1%, lubricating oil (C 22 -C 30 25.2%, heavy oil (C 30 above) 6.4%.

[0079] The obtained pyrolysis gas products were analyzed by gas chromatography to determine the gas composition and content: hydrogen 23.56%, carbon dioxide 15.03%, methane 54.03%, dienes 0.10%, ethane and propane 7.34%, and C4 components 0.09%.

[0080] Example 4

[0081] This embodiment provides an in-situ catalytic conversion method for medium- and low-maturity shale oil or oil shale. Compared with Example 1, the copper oxide nanosheet catalyst is replaced by an equal mass of copper oxide nanosheet catalyst with a nanosheet thickness of 20 nm and a nanosheet diameter of 220 nm. All other aspects are the same as in Example 1.

[0082] To obtain the above-mentioned copper oxide nanosheets, the concentration of the copper nitrate solution was adjusted to 0.2 mol / L and the calcination temperature was adjusted to 600 °C, with all other process parameters being the same as in Preparation Example 1, following the preparation method of Preparation Example 1.

[0083] In this embodiment, the pyrolysis oil and gas recovery rate was calculated to be 8.53% based on the collected pyrolysis oil and gas products, of which the pyrolysis oil recovery rate was 0.43% and the pyrolysis gas recovery rate was 8.10%.

[0084] The obtained pyrolysis oil products were analyzed by simulated distillation chromatography to obtain the distillation range of the pyrolysis oil: gasoline (C5-C5). 12 31.2%, diesel (C 12 -C 22 35.3%, lubricating oil (C 22 -C 30 24.2%, heavy oil (C 30 above) 9.3%.

[0085] The obtained pyrolysis gas products were analyzed by gas chromatography to determine the gas composition and content: hydrogen 23.73%, carbon dioxide 14.03%, methane 53.09%, dienes 0.11%, ethane and propane 9.09%, and C4 components 0.10%.

[0086] Comparative Example 1

[0087] This comparative example provides an in-situ catalytic conversion method for medium- and low-maturity shale oil or oil shale. Compared with Example 1, copper oxide nanosheet catalyst is not added in step (2), and the rest is the same as in Example 1.

[0088] In this comparative example, the pyrolysis oil and gas recovery rate was calculated to be 7.64% based on the collected pyrolysis oil and gas products. Figure 3 As shown, the pyrolysis oil recovery rate was 0.34%, and the pyrolysis gas recovery rate was 7.30%.

[0089] The obtained pyrolysis oil products were analyzed by simulated distillation chromatography, such as... Figure 4 As shown, the distillation range of the pyrolysis oil is obtained: gasoline (C5-C5). 12 22.8% of diesel fuel (C 12 -C 22 39.3%, lubricating oil (C 22 -C 30 29.4%, heavy oil (C 30 and above) 8.5%.

[0090] The obtained pyrolysis gas products were analyzed by gas chromatography to determine the gas composition and content: hydrogen 20.88%, carbon dioxide 14.16%, methane 55.39%, dienes 0.12%, ethane and propane 9.34%, and C4 components 0.11%.

[0091] Compared to Example 1, in this comparative example, no catalyst was added, resulting in a decrease in oil and gas recovery rate. Furthermore, the proportion of heavy oil components such as diesel oil in the pyrolysis oil products was high, leading to a decrease in oil quality.

[0092] Comparative Example 2

[0093] This comparative example provides an in-situ catalytic conversion method for medium- and low-maturity shale oil or oil shale. Compared with Example 1, in step (2), the copper oxide nanosheet catalyst is replaced by commercially available copper oxide powder of equal mass. The copper oxide powder is spherical particles with a particle size range of 600-800 nm. All other aspects are the same as in Example 1.

[0094] In this comparative example, the pyrolysis oil and gas recovery rate was calculated to be 7.39% based on the collected pyrolysis oil and gas products, of which the pyrolysis oil recovery rate was 0.38% and the pyrolysis gas recovery rate was 7.01%.

[0095] The obtained pyrolysis oil products were analyzed by simulated distillation chromatography to obtain the distillation range of the pyrolysis oil: gasoline (C5-C5). 12 30.3%, diesel (C 12 -C 22 33.7%, lubricating oil (C 22 -C 30 27.8%, heavy oil (C 30 above) 8.2%.

[0096] The obtained pyrolysis gas products were analyzed by gas chromatography to determine the gas composition and content: hydrogen 21.79%, carbon dioxide 13.78%, methane 53.21%, dienes 0.08%, ethane and propane 11.07%, and C4 components 0.07%.

[0097] Compared to Example 1, in this comparative example, spherical copper oxide particles were used, resulting in decreased catalytic efficiency, reduced oil and gas recovery rate, and a higher proportion of heavy oil components such as diesel in the pyrolysis oil products, leading to a decrease in oil quality.

[0098] Comparative Example 3

[0099] This comparative example provides an in-situ catalytic conversion method for medium- and low-maturity shale oil or oil shale. Compared with Example 1, in step (2), the copper oxide nanosheet catalyst is replaced by the zinc oxide nanosheet catalyst prepared in Comparative Preparation Example 1 by the same mass, and the rest are the same as in Example 1.

[0100] In this comparative example, the pyrolysis oil and gas recovery rate was calculated to be 5.46% based on the collected pyrolysis oil and gas products, of which the pyrolysis oil recovery rate was 0.19% and the pyrolysis gas recovery rate was 5.27%.

[0101] The obtained pyrolysis oil products were analyzed by simulated distillation chromatography to obtain the distillation range of the pyrolysis oil: gasoline (C5-C5). 12 28.6%, diesel (C 12 -C 22 30.5%, lubricating oil (C 22 -C 30 28.6%, heavy oil (C 30above) 12.3%.

[0102] The obtained pyrolysis gas products were analyzed by gas chromatography to determine the gas composition and content: hydrogen 23.52%, carbon dioxide 15.29%, methane 53.34%, dienes 0.08%, ethane and propane 7.68%, and C4 components 0.09%.

[0103] Compared to Example 1, in this comparative example, zinc oxide nanosheets were used, which had extremely low catalytic activity and would block shale pores, thereby affecting shale cracking. Consequently, the oil and gas recovery rate decreased significantly, and the pyrolysis oil products contained a high content of heavy oil components.

[0104] Thermogravimetric (TGA) and derivative thermogravimetric (DTG) analyses were performed on the mixture obtained by mixing the copper oxide nanosheet catalyst provided in Example 1 with shale, and on the shale powder without catalyst provided in Comparative Example 1. The results are as follows: Figure 6 As shown, the use of copper oxide nanosheet catalysts increases the maximum weight loss of shale by approximately 14.1% during the main pyrolysis stage (300-600℃). Furthermore, the weight loss rate during the asphaltene pyrolysis stage is significantly increased, and the maximum decomposition temperature during the asphaltene decomposition into oil and gas stage is advanced by approximately 50℃.

[0105] In summary, the in-situ catalytic conversion method provided by this invention, utilizing copper oxide nanosheet catalyst, can significantly promote the in-situ pyrolysis of medium- and low-maturity oil shale, effectively improve oil and gas recovery rate, optimize product distribution, and accelerate the conversion of kerogen-asphaltene-oil and gas.

[0106] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. An in-situ catalytic conversion method for medium-to-low maturity shale oil or oil shale, characterized in that, The in-situ catalytic conversion method includes the following steps: Shale was mixed with copper oxide nanosheet catalyst and then subjected to a closed-loop pyrolysis reaction under nitrogen and / or inert gas. The pyrolysis products were collected after the reaction was completed.

2. The in-situ catalytic conversion method according to claim 1, characterized in that, The shale has a grain size ≤ 60 mesh.

3. The in-situ catalytic conversion method according to claim 1 or 2, characterized in that, The amount of the copper oxide nanosheet catalyst used is 0.1-5 wt% of the shale.

4. The in-situ catalytic conversion method according to any one of claims 1-3, characterized in that, The inert gas includes helium and / or argon.

5. The in-situ catalytic conversion method according to any one of claims 1-4, characterized in that, The temperature of the pyrolysis reaction is 300-600℃.

6. The in-situ catalytic conversion method according to any one of claims 1-5, characterized in that, The pressure of the pyrolysis reaction is 0.5-5 MPa.

7. The in-situ catalytic conversion method according to any one of claims 1-6, characterized in that, The thickness of the copper oxide nanosheet catalyst is 5-25 nm. Preferably, the diameter of the copper oxide nanosheet catalyst is 100-300 nm.

8. The in-situ catalytic conversion method according to any one of claims 1-7, characterized in that, The preparation process of the copper oxide nanosheet catalyst includes: mixing a copper salt solution with an alkaline solution to carry out a precipitation reaction, separating the solid and liquid to obtain a precipitate, and calcining the precipitate to obtain the copper oxide nanosheet catalyst.

9. The in-situ catalytic conversion method according to claim 8, characterized in that, The concentration of the copper salt solution is 0.01-0.2 mol / L; Preferably, the concentration of the alkaline solution is 1-5 mol / L.

10. The in-situ catalytic conversion method according to claim 8 or 9, characterized in that, The roasting temperature is 300-600℃; Preferably, the roasting time is 3-5 hours.

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