Method for determining the origin of a crude oil based on thioethyl noradamantane

Abstract

The application provides a method for determining the oil source of crude oil based on thioethyl noradamantane, which comprises the following steps: mixing the crude oil with a solvent to prepare a to-be-tested solution; injecting the to-be-tested solution into an atmospheric pressure electrochemical ionization source, ionizing the to-be-tested solution into ions through the atmospheric pressure electrochemical ionization source, and then performing ion trap high-resolution mass spectrometry analysis to obtain mass spectrometry analysis result data; determining the element information and structure information of thioethyl noradamantane according to the molecular ion mass number and fragment ion mass number in the mass spectrometry analysis result data, and determining the stable isotopes of thioethyl noradamantane 32 S and 34 S signal intensity; determining the isotopic ratio of thioethyl noradamantane according to the formula δ = ‰ x ( 34 R sample / 34 R SF6 ) -1, comparing the isotopic ratio of thioethyl noradamantane with isotopic data of sulfates in known source rocks, and determining the oil source of the crude oil. The application has the advantages of simple process, good repeatability, high efficiency and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of oil and gas exploration and development and paint geochemistry, and particularly relates to a method for determining the oil source of crude oil based on thioethyl noradamantane. BACKGROUND

[0002] Deep oil and gas exploration is an important and realistic field of global oil and gas exploration. Deep oil and gas exploration faces difficulties and problems such as high reservoir temperature, high pressure, complex ground stress, and strong inorganic-organic interaction, which further leads to great risk of deep oil and gas exploration, and the source of deep oil and gas exploration cannot be accurately locked by using traditional methods, and the cracking degree of crude oil is not easy to judge, which greatly limits the implementation of deep resource potential and the assessment of oil and gas exploration prospects. One of the main reasons for the above difficulties and problems is that the deep oil and gas era is old, the source is complex, the maturity is high, and the conventional biomarker compounds have been destroyed, so that valuable information cannot be obtained. Chinese patent document CN105510456A discloses a method for determining the source of high-mature condensate oil, comprising: (1) analyzing and detecting the oil sample to determine whether the oil sample contains thioadamantane compounds; (2) enriching the thioadamantane compounds in the oil sample containing the thioadamantane compounds, the enrichment step comprising: converting the sulfur-containing compounds in the oil sample into sulfonium salt by using methylation reaction, after separating the sulfonium salt, removing the thiophene compounds and sulfide compounds step by step, and then obtaining the enriched thioadamantane compounds; (3) testing the sulfur isotopes of the enriched thioadamantane compounds, and comparing the test results with the sulfur isotope data of the known oil source bed series sulfate, so as to determine the oil source of the oil sample. This method needs to separate and enrich the thiophene compounds and sulfide compounds in the crude oil for many times, the process is complicated, the repeatability is not high, the efficiency is low, and the application of the method is limited. SUMMARY

[0003] The present application provides a method for determining the oil source of crude oil based on thioethyl noradamantane, which has the advantages of simple process, good repeatability, high efficiency, etc., and can effectively overcome the defects existing in the prior art.

[0004] The application provides a method for determining the oil source of crude oil based on thioethyl noradamantane, comprising the following steps: mixing the crude oil with a solvent to prepare a to-be-tested solution; injecting the to-be-tested solution into an atmospheric pressure electrochemical ionization source, ionizing the to-be-tested solution into ions through the atmospheric pressure electrochemical ionization source, and then performing ion trap high-resolution mass spectrometry analysis to obtain mass spectrometry analysis result data; wherein the atmospheric pressure electrochemical ionization source comprises an auxiliary gas containing SF6; the mass numbers of the molecular ion peaks extracted by the quadrupole rod of the ion trap high-resolution mass spectrometer are 180+14n, 232+14n, 284+14n, 336+14n, 388+14n, 440+14n and 492+14n, n is 0 or a positive integer, and the mass numbers of the fragment ion peaks are 91, 105, 79, 81, 119, 131, 145 and 159; the element information and structure information of thioethyl noradamantane are determined according to the mass numbers of the molecular ions and the mass numbers of the fragment ions in the mass spectrometry analysis result data, and the stable isotopes of thioethyl noradamantane are determined according to the mass spectrometry analysis result data 32 S and 34 S signal intensity; the isotopic ratio of thioethyl noradamantane is determined according to the formula δ = ‰ x ( 34 R sample / 34 R SF6 )-1, wherein, 34 R sample is the ratio of the 34 S signal intensity to the 32 S signal intensity of thioethyl noradamantane, 34 R SF6 is the ratio of the 34 S signal intensity to the 32 S signal intensity of the SF6; the isotopic ratio of thioethyl noradamantane is compared with the isotopic data of sulfates in known source rocks, and the oil source of the crude oil is determined according to the comparison result.

[0005] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane, as described above, wherein the to-be-tested solution is injected into the atmospheric pressure electrochemical ionization source at a speed of 1-100 μL / min.

[0006] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane, as described above, wherein the concentration of the to-be-tested solution is 0.01-2.0 mg / mL.

[0007] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane, as described above, wherein the solvent comprises at least one of carbon disulfide, carbon tetrachloride, isooctane and dimethyl sulfoxide.

[0008] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane as described above, wherein the auxiliary gas of the atmospheric pressure ionization source further comprises nitrogen and / or helium, and the volume content of SF6 in the auxiliary gas is 0.1-0.5%.

[0009] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane as described above, wherein the flow rate of the auxiliary gas is 1-25 Ar b.

[0010] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane as described above, wherein the atmospheric pressure chemical ionization source further comprises a sheath gas, and the sheath gas comprises nitrogen and / or helium, and the flow rate of the sheath gas is 1-100 Ar b.

[0011] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane as described above, wherein the atmospheric pressure chemical ionization source further comprises a backflush gas, and the backflush gas comprises nitrogen (N2) and / or helium (He), and the flow rate of the backflush gas is 0.01-1.0 Ar b.

[0012] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane as described above, wherein the conditions of the atmospheric pressure chemical ionization source are: the discharge current is set to 1-40 μA, the ion transfer capillary temperature is set to 200-400 °C, and the evaporator temperature is set to 200-400 °C.

[0013] Further, the method for determining the oil source of crude oil based on thioethyl noradamantane as described above, wherein the ion trap high-resolution mass spectrometer is set to full scan from 50.0 to 800.0 m / z, and the resolution is 100000-700000; and the conditions of the ion trap high-resolution mass spectrometer are: the concentration of the injected ions extracted by the quadrupole rod meets the number of the injected ions (1-9) × 10 5 , the maximum injection time is 10-1000 ms, the number of microscans is 1-10, and the energy of the high-energy collision-induced dissociation is 5-50 eV.

[0014] In the present application, elemental analysis and structural information analysis of thioethyl noradamantane in crude oil are carried out by atmospheric pressure chemical ionization source-ion trap high resolution mass spectrometry, and the isotopic information of thioethyl noradamantane is obtained at the same time, and the oil source of the crude oil is determined based on the analysis results of thioethyl noradamantane, and the process does not need to enrich thioadamantane compounds in the crude oil, the process is simple and easy to operate, and at the same time, the analysis of trace (≤100 ppm) thioethyl noradamantane compounds in the analyzed crude oil can be realized by a small amount of crude oil (≤0.1 g), and the oil source is determined by using the sulfur isotope information recorded by the compounds, the sensitivity is high, the repeatability is good, the process of multiple separation and enrichment is avoided, the time for completing the analysis of one crude oil is not more than 1 hour, the efficiency is high, the large throughput screening can be realized, and the on-site production can be served in time. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a schematic diagram of the chemical structure (molecular formula) of thioethyl noradamantane.

[0016] Figure 2 It is the structural formula of the 5-cage thioethyl noradamantane determined in Example 1 and the mass spectrum of the fragment ion obtained by high-energy collision dissociation (the vertical coordinate is relative abundance (Relative Abundance)). DETAILED DESCRIPTION

[0017] In order for those skilled in the art to better understand the scheme of the present application, the present application will be further described in detail below. The following specific embodiments are only used to describe the principles and characteristics of the present application, and the examples are only used to explain the present application, and do not limit the scope of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0018] The application provides a method for determining the oil source of crude oil based on thioethyl noradamantane, which comprises the following steps: mixing the crude oil with a solvent to prepare a to-be-tested solution; injecting the to-be-tested solution into an atmospheric pressure electrochemical ionization source, ionizing the to-be-tested solution into ions through the atmospheric pressure electrochemical ionization source, and then performing ion trap high-resolution mass spectrometry analysis to obtain mass spectrometry analysis result data; wherein the atmospheric pressure electrochemical ionization source comprises an auxiliary gas containing SF6; the mass numbers of the molecular ion peaks extracted by the quadrupole rod of the ion trap high-resolution mass spectrometer are 180+14n, 232+14n, 284+14n, 336+14n, 388+14n, 440+14n and 492+14n, n is 0 or a positive integer, and the mass numbers of the fragment ion peaks are 91, 105, 79, 81, 119, 131, 145 and 159; the element information and the structure information of the thioethyl noradamantane are determined according to the mass numbers of the molecular ions and the mass numbers of the fragment ions in the mass spectrometry analysis result data, and the stable isotopes of the thioethyl noradamantane are determined according to the mass spectrometry analysis result data 32 S and 34 S signal intensity; the isotopic ratio of the thioethyl noradamantane is determined according to the formula δ = ‰ x ( 34 R sample / 34 R SF6 )-1, wherein, 34 R sample is the ratio of the S signal intensity to the S signal intensity of the thioethyl noradamantane, 34 R 32 is the ratio of the S signal intensity to the S signal intensity of SF6, 34 R SF6 is the ratio of the S signal intensity to the S signal intensity of SF6, 34 R 32 is the ratio of the S signal intensity to the S signal intensity of SF6; the isotopic ratio of the thioethyl noradamantane is compared with the isotopic data of sulfates in known source rocks, and the oil source of the crude oil is determined according to the comparison result.

[0019] In the determination of the oil source of the crude oil, a biomarker with high thermal stability and not susceptible to biodegradation is preferred to be found, and the thioethyl noradamantane has a special chemical structure Figure 1), with very high thermodynamic stability and biological stability, can be selected as a biomarker for determining oil sources, however, how to analyze thioethyl noradamantane in crude oil and how to efficiently and accurately determine the sulfur isotope of thioethyl noradamantane are a difficult problem that has not been solved. The present application can determine the elemental information (molecular formula) and structural information (molecular structure) of thioethyl noradamantane in crude oil through the above determination process, and can further obtain the isotope ratio according to the signal intensity of the stable isotopes 32S and 34S of thioethyl noradamantane in the mass spectrometry result data, and because the sulfur in the sulfur-containing compounds (including thioethyl noradamantane) in the crude oil comes from the sulfate in the source rock, which is transferred to the sulfur-containing compounds through thermal reduction of the sulfate, therefore, the sulfur isotope of thioethyl noradamantane in the crude oil should be similar to the sulfur isotope of the sulfate in the corresponding source rock of the crude oil, if they are not similar, then the crude oil should not come from the source rock, and the greater the difference between the two values, the worse the corresponding relationship. Therefore, if the isotope ratio of thioethyl noradamantane is similar to the isotope data of the sulfate in a known source rock, then the above-mentioned crude oil comes from the known source rock, thereby determining the oil source of the crude oil.

[0020] Generally, there are multiple thioethyl noradamantanes in the crude oil, and the mass spectrometry result data includes the isotope 32 S and 34 S of multiple thioethyl noradamantanes, the isotope ratio of each thioethyl noradamantane is determined according to the formula δ = ‰ x (R 34 R sample / 34 R SF6 )-1, then the average value of the obtained isotope ratios of multiple thioethyl noradamantanes is calculated, and the average value is compared with the isotope data of the sulfate in a known source rock, and the oil source of the crude oil is determined according to the comparison result. Specifically, the signal intensity of the stable isotopes 32 S and 34 S of thioethyl noradamantane is the mass spectrometry peak intensity of the ion with 32 S and the mass spectrometry peak intensity of the ion with 34 S, and the isotope data of the sulfate in the known source rock can be determined according to the determination method of DZ / T 0184.15-1997 Determination of sulfur isotope composition in sulfate.

[0021] In some embodiments, the solution to be tested is injected into the atmospheric pressure chemical ionization source at a speed of 1-100 μL / min, preferably at a speed of 5-50 μL / min, in the atmospheric pressure chemical ionization source, after high-energy collision dissociation, ions (such as molecular ions, etc.) are generated, and then ion trap high-resolution mass spectrometry is performed to obtain mass spectrometry result data.

[0022] In some embodiments, the concentration of the solution to be tested is 0.01-2.0 mg / mL, for example 0.01 mg / mL, 0.05 mg / mL, 0.1 mg / mL, 0.5 mg / mL, 0.8 mg / mL, 1 mg / mL, 1.2 mg / mL, 1.5 mg / mL, 1.8 mg / mL, 2 mg / mL, or a range defined by any two of them, and generally preferably 0.05-0.8 mg / mL.

[0023] The solvent includes at least one of carbon disulfide, carbon tetrachloride, isooctane, dimethyl sulfoxide, for example carbon disulfide or carbon tetrachloride or isooctane or dimethyl sulfoxide. In some preferred embodiments, the solvent includes carbon disulfide and / or isooctane, and when it is a mixed solvent of carbon disulfide and isooctane, the volume ratio of carbon disulfide to isooctane can be (1:9)-(9:1), for example 1:8, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, 9:1, or a range defined by any two of them.

[0024] The auxiliary gas of the atmospheric pressure ionization source assists in ionization, and contains sulfur hexafluoride (SF6) gas, and the mass spectrometry result data includes SF6 34 The S signal intensity is proportional to 32 The S signal intensity, so that the isotopic ratio of thioethyl noradamantane can be determined according to the formula δ=‰× 34 R sample / 34 R SF6 In some embodiments, the auxiliary gas of the atmospheric pressure chemical ionization source further contains nitrogen (N2) and / or helium (He), and the volume content of SF6 therein is 0.1-0.5%, for example 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, or a range defined by any two of them, and the auxiliary gas is for example a mixed gas of N2 and SF6, or a mixed gas of He and SF6. The flow rate of the auxiliary gas of the atmospheric pressure chemical ionization source can generally be 1-25 Arb, for example 1 Arb, 2 Arb, 5 Arb, 8 Arb, 10 Arb, 12 Arb, 15 Arb, 18 Arb, 20 Arb, 22 Arb, 25 Arb, or a range defined by any two of them.

[0025] In addition, the atmospheric pressure chemical ionization source further includes a sheath gas, and the sheath gas includes N2 and / or helium He, and the flow rate of the sheath gas is 1-100 Arb, for example 1 Arb, 5 Arb, 10 Arb, 20 Arb, 30 Arb, 40 Arb, 50 Arb, 60 Arb, 70 Arb, 80 Arb, 90 Arb, 100 Arb, or a range defined by any two of them, and the sheath gas can play a role in atomization, desolvation, etc.

[0026] In addition, the above-mentioned atmospheric pressure chemical ionization source further comprises a back flushing gas, the back flushing gas comprises N2 and / or He, the flow rate of the back flushing gas is 0.01-1.0 Arb, for example, 0.01 Arb, 0.05 Arb, 0.1 Arb, 0.2 Arb, 0.3 Arb, 0.5 Arb, 0.8 Arb, 1.0 Arb or a range between any two of them, and the back flushing gas can be used to back flush the to-be-tested solution into the atmospheric pressure chemical ionization source, so as to make the system more uniform and improve the determination efficiency.

[0027] Specifically, after the to-be-tested solution enters the atmospheric pressure chemical ionization source, the solvent can be evaporated by the evaporator of the atmospheric pressure chemical ionization source, and the crude oil is dissociated into ions in the atmospheric pressure chemical ionization source, and the ions are transferred to the ion trap high-resolution mass spectrometry unit by the ion transfer capillary for mass spectrometry analysis, so as to obtain the mass spectrometry analysis result data. According to the research of the present application, the conditions of the above-mentioned atmospheric pressure chemical ionization source are as follows: the discharge current is set to 1-40 μA, for example, 1 μA, 2 μA, 5 μA, 10 μA, 15 μA, 20 μA, 25 μA, 30 μA, 35 μA, 40 μA or a range between any two of them, the temperature of the ion transfer capillary is set to 200-400 ℃, for example, 200 ℃, 220 ℃, 250 ℃, 280 ℃, 300 ℃, 320 ℃, 350 ℃, 380 ℃, 400 ℃ or a range between any two of them, and the temperature of the evaporator is set to 200-400 ℃, for example, 200 ℃, 220 ℃, 250 ℃, 280 ℃, 300 ℃, 320 ℃, 350 ℃, 380 ℃, 400 ℃ or a range between any two of them, which is beneficial to further improve the determination efficiency.

[0028] Generally, the ion trap high-resolution mass spectrometer can be set to full scan from 50.0 to 800.0 m / z, and the resolution is 100000-700000, preferably, the ion trap high-resolution mass spectrometer is set to full scan from 60.0 to 600.0 m / z, and the resolution is 300000-600000.

[0029] Through further research, the ion trap high-resolution mass spectrometry conditions are as follows: the concentration of the injected ions extracted by the quadrupole rod of the ion trap high-resolution mass spectrometer satisfies that the number of the injected ions is (1-9) × 10 5 , preferably (3-8) × 10 5The injection ion number is generally the total number of molecular ions, the quadrupole ion transfer multistage rod injects ions (the maximum time length is the maximum time length of the quadrupole ion transfer multistage rod injection of the ion trap high-resolution mass spectrometer), high-energy collision dissociation is carried out in the ion transfer multistage rod, and the “fragment ions” formed after collision and the “molecular ions” not collided are sent to the mass spectrometry analysis unit for mass spectrometry analysis, so as to obtain the mass spectrometry analysis result data.

[0030] The present application can determine the oil source of crude oil by using a mass spectrometer according to the above process, which comprises an atmospheric pressure chemical ionization source and an ion trap high-resolution mass spectrometer, and a panel for manipulating the conditions of the atmospheric pressure chemical ionization source and the conditions of the ion trap high-resolution mass spectrometer. In specific implementation, the conditions of the atmospheric pressure chemical ionization source and the conditions of the ion trap high-resolution mass spectrometer can be set on the panel. The mass spectrometer is, for example, an Orbitrap Fusion model mass spectrometer from Thermo Scientific Company, and its control software is Orbitrap Fusion 2.0 Tune.

[0031] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described clearly and completely below in combination with specific embodiments. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. In the following embodiments, an Orbitrap Fusion model mass spectrometer from Thermo Scientific Company is used, and its control software is Orbitrap Fusion 2.0 Tune.

[0032] Embodiment 1

[0033] The method for determining the oil source of crude oil based on thioethyl noradamantane provided in the present embodiment is carried out according to the following process:

[0034] The Lunnan 1 crude oil is dissolved in carbon disulfide to prepare a solution with a concentration of 0.2 mg / mL, which is injected into the atmospheric pressure chemical ionization source at a speed of 20 μL / min; after ionization by the atmospheric pressure electrochemical ionization source, ion trap high-resolution mass spectrometry analysis is carried out to obtain mass spectrometry analysis result data;

[0035] The atmospheric pressure chemical ionization source has a sheath gas of N2 with a flow rate of 20 Arb; an auxiliary gas of N2 containing 0.1 vol% of SF6 gas with a flow rate of 5 Arb; a backflush gas of N2 with a flow rate of 0.5 Arb; a discharge current setting of 10 μA, an ion transfer capillary temperature setting of 350 °C, and an evaporator temperature setting of 400 °C.

[0036] The ion trap high resolution mass spectrometer is set to full scan from 50.0 to 800.0 m / z with a resolution of 500000;

[0037] The mass number of the extracted molecular ion peaks of the ion trap high resolution mass spectrometer is (180+14n, 232+14n, 284+14n, 336+14n, 388+14n, 440+14n, 492+14n, n is 0 and a positive integer) extracted by the quadrupole, the concentration of the injected ions is 5 x 10 5

[0038] The molecular formula (element information) and the molecular structure (structure information) of the thiothioethyl noradamantane are determined by the molecular ion mass numbers (180+14n, 232+14n, 284+14n, 336+14n, 388+14n, 440+14n, 492+14n, n is 0 and a positive integer) and the fragment ion mass numbers (91, 105, 79, 81, 119, 131, 145, 159) in the mass spectrometry analysis result data, wherein the structure formula of the 5-cage thioethyl noradamantane and the fragment ion mass spectrum obtained by high-energy collision dissociation are shown in Figure 2 ;

[0039] The signal intensity of the stable isotopes 32 S and 34 S of different thioethyl noradamantanes is compared with that of SF6 gas to obtain the isotopic ratio (i.e. according to the formula δ = ‰ x 34 R sample / 34 R SF6 ​)1determined the isotopic ratio of thioethyl noradamantane, it was calculated that the monomer δ of thioethyl noradamantane compound in the Luntan 1 crude oil was +36.5~39.6, and the average value was +37.6; the isotopic distribution range of the sulfate in the Cambrian source rock of the basin where the crude oil was located was 33.5~38.0, and the average value was +35.5; the isotopic distribution range of the sulfate in the Ordovician source rock of the basin was 21.1~24.6, and the average value was +23.6; obviously, the monomer sulfur isotopes of thioethyl noradamantane compound in the Luntan 1 crude oil were more close to the isotopes of the sulfate in the Cambrian source rock; since the thioethyl noradamantane was formed by the thermal cracking of the sulfate in the ethyl noradamantane compound and the sulfate in the source rock, the monomer sulfur isotope information of the thioethyl noradamantane compound indicated the original information of the source rock, and the thioethyl noradamantane compound had a stable cage structure in physical and chemical properties, and would not be disturbed by other secondary actions, so it could be judged that the Luntan 1 crude oil came from the Cambrian source rock of the basin.

[0040] Example 2

[0041] The method for determining the oil source of the crude oil based on the thioethyl noradamantane provided in the embodiment is carried out according to the following process:

[0042] The Gaogan 1 crude oil was dissolved in dimethyl sulfoxide to prepare a solution with a concentration of 2.0 mg / mL, and was injected into an atmospheric pressure chemical ionization source at a speed of 100 μL / min; after ionization by the atmospheric pressure chemical ionization source, the ion was analyzed by an ion trap high-resolution mass spectrometer to obtain mass spectrometry result data;

[0043] The sheath gas of the atmospheric pressure chemical ionization source was He, and the flow rate was 95 Arb; the auxiliary gas was He containing 0.5 vol% SF6 gas, and the flow rate was 24 Arb; the backflush gas was He, and the flow rate was 1.0 Arb; the discharge current was set to 36 μA, the ion transfer capillary temperature was set to 400 ℃, and the evaporator temperature was set to 400 ℃;

[0044] The ion trap high-resolution mass spectrometer was set to full scan from 50.0 to 800.0 m / z, and the resolution was 680000;

[0045] The mass numbers of the molecular ion peaks extracted by the ion trap high-resolution mass spectrometer were (180+14n, 232+14n, 284+14n, 336+14n, 388+14n, 440+14n, 492+14n, n was 0 and a positive integer), the concentration of the injected ions extracted was 9×10 5 ions, the maximum injection time was 1000 ms, the number of microscans was 10, and the energy of the high-energy collision-induced dissociation was 20 eV;

[0046] The molecular formula (elemental information) and molecular structure (structural information) of thiothioethylnoradamantane were determined by combining the molecular ion mass numbers (180+14n, 232+14n, 284+14n, 336+14n, 388+14n, 440+14n, n is 0 and positive integer) and fragment ion mass numbers (91, 105, 79, 81, 119, 131, 145, 159) in the mass spectrometry analysis data.

[0047] Stable isotopes of different thioethyl noradamantane 32 S and 34 The isotope ratio is obtained by comparing the signal strength of S with that of SF6 gas (i.e., according to the formula δ = ‰ × ( 34 R sample / 34 R SF6 (-1) Determining the isotopic ratios of thioethylnoradamantane), the monomeric δ of the thioethylnoradamantane compound in Gaotan 1 crude oil was calculated to be +26.0–29.9, with an average of +27.0. Meanwhile, the isotopic distribution of sulfate in the Jurassic source rocks of the basin containing this crude oil ranges from 23.3 to 27.1, with an average of +25.4; the isotopic distribution of sulfate in the Triassic source rocks of the same basin ranges from 31.2 to 33.9, with an average of +32.5; and the isotopic distribution of sulfate in the Permian source rocks of the same basin ranges from 35.0 to 38.8, with an average of +... 36.6. Obviously, the sulfur isotopes of the thioethyl-noradamantane compound in the Gaotan 1 crude oil are closer to the isotopes of sulfates in the Jurassic source rocks. Since the thioethyl-noradamantane compound is formed by the sulfate thermal decomposition of ethyl-noradamantane compound and sulfates in the source rocks, the sulfur isotope information of the thioethyl-noradamantane compound indicates the original information of its source rocks. Moreover, the thioethyl-noradamantane compound has a cage-like structure with stable physicochemical properties and will not be disturbed by other secondary processes. Therefore, it can be determined that the Gaotan 1 crude oil comes from the Jurassic source rocks of this basin.

[0048] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for determining the oil source of a crude oil based on thioethyl noradamantane, characterized in that, The method comprises the following steps: Mixing crude oil and solvent to obtain a test solution; wherein the mass of the crude oil is less than or equal to 0.1 g; Injecting the test solution into an atmospheric pressure electrochemical ionization source, ionizing the test solution into ions by the atmospheric pressure electrochemical ionization source, and then analyzing the ions by an ion trap high-resolution mass spectrometer to obtain mass spectrometry result data; wherein The atmospheric pressure electrochemical ionization source comprises an auxiliary gas containing SF6; The mass numbers of the molecular ion peaks extracted by the ion trap high-resolution mass spectrometer are 180+14n, 232+14n, 284+14n, 336+14n, 388+14n, 440+14n, and 492+14n, wherein n is 0 or a positive integer, and the mass numbers of the fragment ion peaks are 91, 105, 79, 81, 119, 131, 145, and 159; determining the elemental information and structural information of the thioethyl noradamantane according to the molecular ion mass number and fragment ion mass number in the mass spectrometric analysis result data, and determining the stable isotope of the thioethyl noradamantane according to the mass spectrometric analysis result data 32 S and 34 S signal intensity; According to the formula δ = (‰ x (R 34 R sample / 34 R SF6 ) -1 determines the isotopic ratio of thioethyl noradamantane, wherein, 34 R sample is the 34 S signal intensity of thioethyl noradamantane, 32 S signal intensity of SF6, 34 R SF6 is the 34 S signal intensity of SF6, 32 S signal intensity of SF6; Comparing the isotopic ratio of the thioethyl noradamantane with the isotopic data of sulfates in known source rocks, and determining the oil source of the crude oil according to the comparison result.

2. The method for determining the crude oil source based on thioethyl noradamantane according to claim 1, characterized in that, The test solution is injected into the atmospheric pressure electrochemical ionization source at a speed of 1-100 µL / min.

3. The method for determining the source of crude oil based on thioethyl noradamantane according to claim 1 or 2, characterized in that, The concentration of the test solution is 0.01-2.0 mg / mL.

4. The method for determining the crude oil source based on thioethyl noradamantane according to claim 1, characterized in that, The auxiliary gas of the atmospheric pressure electrochemical ionization source further comprises nitrogen and / or helium, and the volume content of SF6 in the auxiliary gas is 0.1-0.5%.

5. The method for determining the crude oil source based on thioethyl noradamantane according to claim 1 or 4, characterized in that, The flow rate of the auxiliary gas is 1-25 Arb.

6. The method for determining the source of crude oil based on thioethyl noradamantane according to claim 1, characterized in that, The atmospheric pressure electrochemical ionization source further comprises a sheath gas, and the sheath gas comprises nitrogen and / or helium, and the flow rate of the sheath gas is 1-100 Arb.

7. The method for determining the crude oil source based on thioethyl noradamantane according to claim 1, characterized in that, The atmospheric pressure electrochemical ionization source further comprises a backflush gas, and the backflush gas comprises nitrogen and / or helium, and the flow rate of the backflush gas is 0.01-1.0 Arb.

8. The method for determining the crude oil source based on thioethyl noradamantane according to claim 1 or 4, characterized in that, The conditions of the atmospheric pressure electrochemical ionization source are as follows: the discharge current is set to 1-40 µA, the ion transfer capillary temperature is set to 200-400 ℃, and the evaporator temperature is set to 200-400 ℃.

9. The method for determining the crude oil source based on thioethyldiamantane according to claim 1 or 2, characterized in that, The ion trap high-resolution mass spectrometer is set to full scan from 50.0 to 800.0 m / z, and the resolution is 100000~700000; the ion trap high-resolution mass spectrometer analysis conditions are: the concentration of the injection ions extracted by the quadrupole rod meets the injection ion number of (1~9)×10 5 , the maximum injection time is 10~1000 ms, the micro scanning number is 1~10, and the high-energy collision dissociation energy is 5~50 eV.

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