A method and application for identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis

Abstract

The present invention relates to a method for identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis, comprising the following steps: S1, enclosing reactants of a catalytic hydrogenation simulation experiment in an inert material reaction system and heating them to obtain simulated experimental products of the experimental group and the control group; S2, testing the simulated experimental products of the experimental group and the control group to obtain chemical characteristics of the simulated experimental products of the experimental group and the control group; S3, based on the obtained chemical characteristics, analyzing the yield of mono-carbon gas and the carbon isotope variation characteristics of the mono-carbon gas in the simulated experimental products, thereby identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis. The method can effectively identify the degree of influence of Fischer-Tropsch synthesis on the catalytic hydrogenation process of highly mature source rocks, and thus effectively serves the scientific theoretical research of oil and natural gas.

Description

Technical Field

[0001] The present invention belongs to the field of oil and gas geochemistry, and specifically relates to a method for identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis, and more specifically relates to a method for identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis during the hydrocarbon generation reaction process of high-maturity source rocks. Background Art

[0002] The Fischer-Tropsch synthesis (FTS) reaction, commonly used in the chemical industry, involves mixing relatively simple gases (CO + H2) to form syngas. Under suitable catalysts and reaction conditions, it generates hydrocarbons of varying chain lengths and oxygenated organic compounds. This reaction can be used to convert complex carbon-containing resources such as coal, natural gas, and biomass into clean energy, primarily CH4, on a large scale. While the reactants are simply CO and H2, the reaction products can reach over hundreds of types, including alkanes ranging from methane to paraffins, alkenes, and a variety of oxygenated organic compounds. The composition and distribution of these products vary under different operating conditions. Previous studies have shown that under specific catalytic conditions, CO2 and H2 can also directly synthesize methane (C1) and high-purity liquid gasoline hydrocarbons. Therefore, the FTS reaction is a well-established technology for synthesizing hydrocarbons in the petrochemical industry.

[0003] In nature, Fischer-Tropsch synthesis is an important way to form primitive organic molecules in meteorites, and it is also an important way for the formation of primitive organic molecules in meteorites after serpentinization of ultrabasic rocks in the oceanic crust and dissolved HCO3 - Recent researchers have detected more product components through improved Fischer-Tropsch synthesis simulation experiments. Furthermore, as the degree of Fischer-Tropsch synthesis increases, the carbon isotope sequence of alkane gases gradually changes from reverse to inverted and then back to normal under the condition of continuous external energy replenishment.

[0004] Previous researchers have found that organic CO2 and H2 formed by serpentinization can undergo Fischer-Tropsch synthesis and generate C1 in serpentinized peridotite at a temperature below 100℃. 3 He ratio and C1 / 3 He ratio and other factors have established a crust-mantle end-member natural gas mixing model. In the Songliao Basin in my country, C1 gas formed by Fischer-Tropsch synthesis of CO2 and H2 was found in the Qingshen gas field. This inorganic C1 is mixed with organic C1, and the content of inorganic C1 exceeds 25%, which has the resource potential to form an independent reservoir.

[0005] Similarly, in deep fault zones and sedimentary basin basements, the process of catalytic hydrogenation of deep hydrogen-rich fluids accompanied by the thermal cracking of organic matter to produce oil and gas has undergone significant changes. In this process, hydrogen-rich fluids introduce hydrogen-rich substances such as H2 into the oil and gas basins, becoming exogenous hydrogen outside the source rocks. This exogenous hydrogen has a significant role in promoting hydrocarbon generation from organic matter. During the catalytic hydrogenation of highly mature source rocks with hydrogen-rich fluids, whether the product CO2 will undergo secondary reactions to produce hydrocarbons has been lacking exploration and practical theoretical breakthroughs. How to effectively distinguish between Fischer-Tropsch synthesis methane and mantle-derived C1 and methane formed by thermal cracking of organic matter still faces many geological and geochemical challenges. Summary of the Invention

[0006] In response to the deficiencies in the prior art, the present invention provides a method for identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis. The method conducts a catalytic hydrogenation simulation experiment on highly mature source rocks in a closed system of inert materials, and simulates the quantitative changes in the relative yields of the products methane (C1) and CO2 before and after catalytic hydrogenation under simulated geological conditions, as well as the qualitative changes in the carbon isotope characteristics, thereby effectively identifying the extent of the influence of Fischer-Tropsch synthesis on the catalytic hydrogenation process of highly mature source rocks.

[0007] To this end, a first aspect of the present invention provides a method for identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis, which comprises the following steps:

[0008] S1, enclosing the reactants of the catalytic hydrogenation simulation experiment of the experimental group and the control group in an inert material reaction system and heating them to obtain the simulation experimental products of the experimental group and the control group;

[0009] S2, detecting the simulated experimental products of the experimental group and the control group to obtain chemical characteristics of the simulated experimental products of the experimental group and the control group;

[0010] S3, analyzing the yield of the mono-carbon gas and the carbon isotope variation characteristics of the mono-carbon gas in the simulation experiment product based on the obtained chemical characteristics, and then identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis.

[0011] Through the above method of the present invention, the contribution of organic-inorganic interaction in the process of hydrocarbon source rock to "promoting hydrocarbon" and "increasing hydrocarbon" can be evaluated more scientifically.

[0012] In some embodiments of the present invention, in step S1, the reaction system is free of carbon-containing gas. In the present invention, an inert gas may be used to replace the gas in the reaction system introduced into the reactants, thereby eliminating any carbon-containing gas from the reaction system. The replacement time is determined by the volume of the reaction system, based on the absence of atmospheric components, such as N2, CO2, O2, etc., detected between the reaction systems.

[0013] In some specific embodiments of the present invention, the reactants in the catalytic hydrogenation simulation experiment of the experimental group include highly mature source rock, catalyst, and water; preferably, the mass ratio of the highly mature source rock, water, and catalyst is (5-10):(5-10):(0.5-1). For example, the mass ratio of the highly mature source rock, water, and catalyst can be 10:10:1.

[0014] In other specific embodiments of the present invention, the reactants in the catalytic hydrogenation simulation experiment in the control group include hydrogen in addition to the highly mature source rock, catalyst, and water described in the experimental group. Preferably, the mass ratio of the highly mature source rock, water, catalyst, and hydrogen is (5-10):(5-10):(0.5-1):(0.1-0.16). For example, the mass ratio of the highly mature source rock, water, catalyst, and hydrogen can be 10:10:1:0.16 to ensure sufficient hydrogen injection during the experiment.

[0015] The highly mature source rock, catalyst, and water in the experimental and control groups described in the present invention are identical; the only difference is the addition of hydrogen to the reactants in the control group. By setting up these experimental and control groups, controlled experiments with and without H2 addition were conducted under the two catalyst conditions. Based on the chemical characteristics of the products from the experimental and control groups, quantitative changes in the relative yields of methane (C1) and CO2 before and after catalytic hydrogenation, as well as qualitative changes in their carbon isotope profiles, were determined.

[0016] In the present invention, the "high-maturity source rock" belongs to the category of source rock geochemistry in petroleum geology, and generally refers to the equivalent category indicated by the vitrinite reflectance (Ro) in organic matter being greater than or equal to 1.90 and other indicators. This type of organic matter has been proven to have weak hydrocarbon generation potential using conventional simulation experimental methods.

[0017] In the present invention, the catalyst is selected with reference to Zn and Mo, which are relatively high in metal content in the fluid under deep geological conditions.

[0018] In some embodiments of the present invention, the catalyst is selected from at least one of ZnCl2 solid powder and MoS2 solid powder. The particle size of the ZnCl2 solid powder and the MoS2 solid powder can be 200 mesh and both meet the requirements of experimental analytical purity.

[0019] In the present invention, the inert material reaction system includes but is not limited to a gold tube reactor, the main feature of which is that the reactor material does not participate in the reaction and has a certain pressure-bearing performance by itself or through external technical means.

[0020] In the present invention, the process for loading the experimental reactants into a sealed gold tube reactor can be as follows: For solid-liquid loading without hydrogen addition (experimental group), after cleaning and welding one end of the gold tube, a predetermined ratio of catalyst (solid), highly mature source rock (solid), and water (liquid) reactants are added to the tube. The tube is then placed in an inert gas environment for a predetermined period of displacement. The displacement time is determined by the volume of the gold tube and is based on the absence of atmospheric components such as N2, CO2, and O2 between the reactors. After displacement, the gold tube walls are flattened using household tools, including but not limited to manual pliers, and the top port is sealed using welding methods, including but not limited to argon arc welding, to complete the loading. For quantitative loading with gaseous reactants (control group), after the initial injection of the solid-liquid reactants, H2 (including a small amount of He as an internal standard gas) is quantitatively injected. The temperature of the injected gas is controlled to be the same as the ambient temperature of the reactants and the reactor. For ease of operation, this operation is generally performed at room temperature. Monitor the H2 injection rate using a highly sensitive device, such as a pressure gauge. Use hydrogen gas to eliminate air interference. Seal the reactor using the aforementioned method and inspect its tightness. If the reactor does not meet the airtightness requirements, repeat the above steps until the reactor meets the requirements.

[0021] In some specific embodiments of the present invention, in step S1, the heating temperature is 350-550° C., and the heating time is 60-72 hours.

[0022] In some embodiments of the present invention, in step S2, the detection includes measuring the yield of the mono-carbon gas in the simulation experiment product and the carbon isotope composition characteristics of the mono-carbon gas.

[0023] In other embodiments of the present invention, the one-carbon gas includes but is not limited to methane and CO2.

[0024] In the present invention, the specific steps of the detection may be: after the heating is completed, the inert material reaction system (gold tube) is taken out from the heating furnace and placed in a sealed container that can maintain a relatively high vacuum environment. The present invention is achieved by including but not limited to customized vacuum glass tubes. The gold tube is opened in the aforementioned sealed container to release the gas. Two valves in series connect the vacuum tube and the chromatograph to measure the yield of gas components such as methane (C1) and CO2. For carbon isotope δ 13 C detection and analysis are carried out using a gas chromatography isotope mass spectrometer with reference to the VPDB standard. Each sample detection data value must be measured three times, and the average value is taken as the sample isotope detection value. The carbon isotope analysis accuracy is required to be within ±0.4‰.

[0025] In the present invention, the reactant loading step and the detection step of the above-mentioned simulation experiment are the experimental parts for obtaining the technical basic data of the present invention. Reference can be made to the literature: Chinese Science Bulletin, Volume 43, 1998, pages 1908-1912 and Patent CN201810228157.8 (Liu Jinzhong et al., 2020).

[0026] In some embodiments of the present invention, in step S3, after analysis, the relative change K of CO2 yield in the control group simulation experiment product with temperature change in the low temperature stage is CO2 ≈0; the temperature of the low temperature stage is ≤400°C. The practical significance of this result is that under the conditions of rich hydrogen and catalyst, the potential of Fischer-Tropsch synthesis to consume CO2 is greater than the potential of organic matter to release CO2 by cracking before this temperature point.

[0027] In other embodiments of the present invention, in step S3, after analysis, compared with the methane yield and CO2 yield in the simulated experimental product of the experimental group, the reduction in CO2 yield and the increase in methane yield in the control group after the addition of hydrogen are linearly related, and the fitting coefficient R 2 ≥0.90. This indicates that the decrease in CO2 production in the control group after hydrogen addition is highly correlated with the increase in methane production. This is due to two factors: first, CO2 and H2 undergo a Fischer-Tropsch synthesis reaction over the catalyst, producing methane (C1); second, because the kerogen in the highly mature source rock itself has a weak ability to generate hydrocarbons through thermal cracking, there is less interference from the cracking of other long-chain hydrocarbons.

[0028] In some embodiments of the present invention, in step S3, after analysis, the carbon isotope composition of the carbon gas in the simulated experimental product of the control group is characterized by a heavier carbon isotope composition of CO2 and a lighter carbon isotope composition of methane compared to the experimental group. This is because during the Fischer-Tropsch synthesis process, the relatively light carbon isotope composition of 12 C CO2 Will preferentially participate in the reaction to produce methane 12 C1.

[0029] In the present invention, the yield of the carbon gas in the simulation experiment product is analyzed, specifically including:

[0030] Methane yield increases steadily from low to high temperatures. Comparisons of different catalysts, including but not limited to ZnCl2 and MoS2, show that while methane yields vary, the trend of increasing methane yield with increasing temperature remains unchanged. For example, the maximum methane yield under ZnCl2 is 1.4 times that of MoS2. After adding H2 to the reaction, the maximum methane yields are 1.8 and 2.1 times those under ZnCl2 and MoS2, respectively.

[0031] The CO2 yield has similar characteristics to that of methane, with both having a tendency to increase with increasing temperature, and different catalysts have different effects on the CO2 yield. For example, the maximum CO2 yield under ZnCl2 is 1.4 times that of MoS2; after adding H2, the maximum CO2 yield is 0.39 to 0.40 times that under ZnCl2 and MoS2, respectively. Among them, within 400℃, the CO2 yield is almost constant with increasing temperature, and the relative change of CO2 yield with increasing temperature is K. C02 ≈0, the reduction in CO2 yield (△CO2) and the increase in methane (△C1) before and after hydrogenation are highly correlated, and the fitting coefficient R 2 ≥0.90.

[0032] In the present invention, the carbon isotope composition characteristics of the mono-carbon gas in the simulation experiment product are analyzed, specifically including:

[0033] For methane, δ 13 The C1 value gradually becomes heavier with increasing temperature, and the influence of catalyst type is obvious. For example, after the blank control reaction of catalyst ZnCl2 and MoS2, δ 13 The C1 value ranges were -44.7~-36.7‰ and -43.6~-36.2‰ respectively; but after H2 was added into the reaction system, δ 13 The change of C1 is relatively mild. For example, after the catalysts ZnCl2 and MoS2 are added with H2 for the control reaction, δ 13 The C1 value ranges were -45.9 to -40.2‰ and -52.4 to -43.4‰, respectively, indicating that the addition of exogenous H2 can significantly promote the activity 12 C hydrocarbon generation, and due to 12 C- 12 The bond energy of C is less than 12 C- 13 C bond energy, δ 12 C1 is produced preferentially during the reaction, resulting in a lighter fractionation with increasing catalytic hydrogenation intensity.

[0034] For CO2δ 13 The experimental results of the control group (hydrogenation group) and the experimental group (non-hydrogenation group) show that the product CO2 of the hydrogenation group has a δ 13 The C value is relatively large, which is consistent with the δ 13 The C value fractionation change is negatively correlated. This is because in the high temperature catalytic H2+CO2→CH4+H2O reaction process, the CO2 12 C will preferentially participate in the reaction 12 C1, resulting in the remaining CO2 13 C enriched and became heavier.

[0035] In summary, the method of the present invention for identifying the Fischer-Tropsch synthesis mechanism during catalytic hydrogenation of highly mature source rocks mainly achieves effective identification through quantitative analysis of changes in carbon gas yield and qualitative analysis of carbon isotope change characteristics.

[0036] A second aspect of the present invention provides an application of the method according to the first aspect of the present invention in identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis during catalytic hydrogenation of source rocks.

[0037] The present invention has the following beneficial effects: The method can identify the inorganic hydrocarbon generation component of the normal organic hydrocarbon generation process, which is meaningful for evaluating hydrocarbon generation efficiency. During the catalytic hydrogenation of highly mature source rocks, significant CO2 and methane (C1) yield and carbon isotope comparisons are observed. These relative yields and carbon isotope comparisons reveal the significant contribution of Fischer-Tropsch synthesis to the catalytic hydrogenation of organic matter, such as highly mature source rocks, and provide authentic, objective, and constructive guidance for the evaluation of oil and gas resources in geological bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be further described below with reference to the accompanying drawings.

[0039] Figure 1 This is a comparison chart of the changes in △CH4 increase and △CO2 decrease under catalytic hydrogenation control conditions.

[0040] Figure 2 is the δ of the products CO2 and methane (C1) under ZnCl2 catalytic conditions with H2 and without H2. 13 C change comparison chart. DETAILED DESCRIPTION

[0041] To make the present invention easier to understand, the present invention will be further described in detail below with reference to the following examples. These examples are merely illustrative and are not intended to limit the scope of application of the present invention. The raw materials or components used in the present invention can be obtained by commercial routes or conventional methods unless otherwise specified.

[0042] Example 1

[0043] The highly mature source rock used in this embodiment is the kerogen of the Yurtusi Formation source rock of the Lower Cambrian in the Tarim region of Xinjiang. Its kerogen has a total organic carbon content TOC of 64.0%, a thermal evolution maturity Ro of 1.91%, kerogen pyrolysis parameters S1 = 1.43 mg / g (kerogen), S2 = 10.95 mg / g (kerogen), S3 = 16.17 mg / g (kerogen), hydrogen index HI = 18, and oxygen index OI = 28.

[0044] 1.1 Loading of reactants in the catalytic hydrogenation simulation experiment of the experimental group and the control group

[0045] Experimental group: After welding and sealing one end of a gold tube and cleaning it, a fixed amount of catalyst (ZnCl2 or MoS2), kerogen from the Lower Cambrian Yurtusi Formation source rock in the Tarim region of Xinjiang, and water were added to the tube in a set ratio of 1:10:10. The tube was placed in an argon environment for 25 minutes to completely displace the air in the tube. The gold tube wall was flattened with manual pliers, and the top port was sealed using argon arc welding to complete the filling.

[0046] Control group: After the initial catalyst, kerogen from the Lower Cambrian Yurtusi Formation source rock in the Tarim region of Xinjiang, and water were injected at a ratio of 1:10:10, H2 (including a small amount of He as an internal standard gas) was quantitatively injected at a hydrogen to catalyst mass ratio of 0.16:1. The temperature of each reactant must be kept consistent; for ease of operation, the reaction can be performed at room temperature. A highly sensitive pressure gauge in series was used to ensure the amount of H2 injected. The air was displaced with hydrogen, and the gold tube reaction system was sealed. This sealing method can be performed using methods including, but not limited to, argon arc welding, and the gas seal within the tube was checked for good sealing.

[0047] 1.2 Detection of chemical characteristics of the simulated experimental products in the experimental and control groups

[0048] After the gold tube is placed in a heating furnace and heated to a set temperature (350°C to 550°C) and time (72h), it is removed from the heating furnace and placed in a sealed environment that can maintain a vacuum. After connecting to the detection system, the gold tube is opened to release the gaseous product. Two valves in series connect the vacuum tube and the chromatograph to measure the yield of gas components such as methane (C1) and CO2. 13 C detection and analysis are carried out using a gas chromatography isotope mass spectrometer with reference to the VPDB standard. Each sample detection data value must be measured three times, and the average value is taken as the sample isotope detection value. The carbon isotope analysis accuracy is required to be within ±0.4‰.

[0049] 1.3 Analysis of simulation experiment products

[0050] As one of the main modes of inorganic hydrocarbon generation, Fischer-Tropsch synthesis provides a good reducing environment and material supply conditions in the catalytic addition of H2 experiment, such as Figure 1 As shown in the figure, the relationship between the CO2 yield reduction △CO2 and the methane (C1) yield increase △C1 under ZnCl2 catalytic hydrogenation is y=1.1359x-17.687, and the fitting coefficient R 2=0.9375; Under the condition of MoS2 catalytic hydrogenation, the relationship between △CO2 and △C1 changes to y=2.1496x-97.873, and the fitting coefficient R2=0.9533. If the reaction changes steadily at 400℃, the relationship between △CO2 and △C1 changes to y=1.9199x-73.472, and the fitting coefficient R 2 The value of the coefficient of catalytic activity (C1) is 0.9921, indicating a good linear relationship between the decrease in CO2 yield after hydrogenation and the increase in methane (C1), indicating a significant causal relationship. Furthermore, the slope of the equation indicates that different catalysts have different effects, with ZnCl2 exhibiting a superior catalytic effect on kerogen hydropyrolysis to hydrocarbon generation compared to MoS2.

[0051] After H2 participates in the hydrocarbon generation reaction, the CO2 yield decreases significantly, but remains stable after reaching a certain value. Yield changes steadily under different temperatures, and isotopic variations also show a shift from heavy to light, followed by a sustained overall stable trend. Hydrogenation inhibits decarboxylation, and the generated CO2 undergoes Fischer-Tropsch synthesis with H2, leading to a significant decrease in CO2 yield. Control group experimental results show that the final CO2 conversion rate is constant under different catalysts, presumably determined by the amount of activated carbon after the addition of H2, indicating that not all reactants in the geological environment reaction process ultimately react.

[0052] During the catalytic hydrogenation of highly mature kerogen, the addition of exogenous H2 to the reaction will cause the carbon isotope composition of CO2 to become heavier and the carbon isotope composition of methane to become lighter. Combined with the significant decrease in the CO2 yield during the addition of H2, this is because kerogen is preferentially generated during the pyrolysis process. 12 CO2 participates in the reaction, promoting the product 12 C1 generates Figure 2 ), the above well reveals the contribution of Fischer-Tropsch synthesis in the catalytic hydrogenation process of organic matter in highly mature source rocks.

[0053] The catalytic addition of H2 occurs in a neutral-reducing system, while the Fischer-Tropsch synthesis with CO2 produces hydrocarbons, significantly impacting the overall hydrocarbon yield. Therefore, as an organic-neutral reaction, Fischer-Tropsch synthesis plays an important role in promoting secondary hydrocarbon generation in highly mature source rocks, providing valuable guidance for the evaluation of oil and gas resources in geological bodies.

[0054] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation of the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis, comprising the following steps: S1, enclosing reactants of the catalytic hydrogenation simulation experiment of the experimental group and the control group in an inert material reaction system and heating them to obtain simulation experimental products of the experimental group and the control group; the reactants of the catalytic hydrogenation simulation experiment of the experimental group include highly mature source rocks, a catalyst, and water; the reactants of the catalytic hydrogenation simulation experiment of the control group include, in addition to the highly mature source rocks, the catalyst, and water described in the experimental group, hydrogen; the catalyst is selected from at least one of Zn and Mo; the heating temperature is 350-550° C.; S2, detecting the simulated experimental products of the experimental group and the control group to obtain chemical characteristics of the simulated experimental products of the experimental group and the control group; S3, analyzing the yield of the mono-carbon gas and the carbon isotope variation characteristics of the mono-carbon gas in the simulation experiment product based on the obtained chemical characteristics, and then identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis.

2. The method according to claim 1, characterized in that In step S1, the reaction system does not contain carbon-containing gas.

3. The method according to claim 2, characterized in that In step S1, the mass ratio of the highly mature source rock, water and catalyst is (5-10):(5-10):(0.5-1); and / or the mass ratio of the highly mature source rock, water, catalyst and hydrogen is (5-10):(5-10):(0.5-1):(0.1-0.16).

4. The method according to any one of claims 1 to 3, wherein the catalyst is selected from at least one of ZnCl2 solid powder and MoS2 solid powder.

5. The method according to any one of claims 1 to 3, characterized in that In step S1, the heating time is 60 to 72 hours.

6. The method according to any one of claims 1 to 3, characterized in that In step S2, the detection includes measuring the yield of the mono-carbon gas in the simulation experiment product and the carbon isotope composition characteristics of the mono-carbon gas.

7. The method according to any one of claims 1 to 3, characterized in that The one-carbon gas includes but is not limited to methane and CO2.

8. The method according to any one of claims 1 to 3, characterized in that In step S3, after analysis, the CO2 yield in the control group simulation experiment product changes with the temperature at the low temperature stage. CO2 ≈0; the temperature of the low temperature stage is ≤400°C.

9. The method according to any one of claims 1 to 3, characterized in that In step S3, after analysis, compared with the methane yield and CO2 yield in the simulated experimental product of the experimental group, the reduction in CO2 yield and the increase in methane yield in the control group after the addition of hydrogen were linearly related, and the fitting coefficient R 2 ≥0.

90.

10. The method according to any one of claims 1 to 3, characterized in that In step S3, after analysis, compared with the experimental group, the carbon isotope composition characteristics of the carbon gas in the simulated experimental product of the control group are that the carbon isotope composition of CO2 becomes heavier and the carbon isotope composition of methane becomes lighter.

11. Use of the method according to any one of claims 1 to 10 in identifying the hydrocarbon generation mechanism of Fischer-Tropsch synthesis during catalytic hydrogenation of source rocks.

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