A method for analyzing thioadamantane compounds in crude oil and determining the oil source

Abstract

The present invention discloses a method for analyzing thioadamantane compounds in crude oil and determining the oil source, the method comprising: (1) using an atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry to analyze and detect the crude oil to be tested, and determining the molecular formula and molecular structure of the thioadamantane in the crude oil; (2) using an atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry to detect the stable isotopes of the thioadamantane in the crude oil. 32 S and 34 The signal intensity of S is measured, and the sulfur isotope ratio δ is obtained by comparing it with SF6 gas. The sulfur isotope ratio δ is compared with the isotope data of sulfate in the known source rock to determine the source of the crude oil. The method of the present invention realizes the analysis of trace (≤100ppm) thioadamantane compounds in crude oil by using a very small amount of crude oil (≤0.1g), and determines the oil source by using the sulfur isotope information recorded by the compounds. It has high sensitivity and good repeatability, and avoids the experimental steps of multiple manual separation and enrichment.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas field exploration and development and oil and gas geochemistry, and in particular to a method for analyzing thioadamantane compounds in crude oil and determining the oil source. Background Art

[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 geostress, and strong inorganic-organic interactions, which lead to great risks in deep oil and gas exploration. Using traditional methods, it is impossible to accurately lock the source of deep oil and gas exploration, and it is not easy to judge the degree of cracking of crude oil, which greatly limits the realization of deep resource potential and the evaluation of oil and gas exploration prospects. One of the main reasons for the above difficulties and problems is that deep oil and gas are ancient, with complex sources and high maturity. Conventional biomarker compounds have been destroyed and valuable information cannot be obtained.

[0003] CN105510456A provides a method for determining the source of highly mature condensate oil. The method requires multiple separation and enrichment of thiophene compounds and sulfide compounds in crude oil. The steps are relatively complicated and difficult for relevant technical personnel to master. The repeatability is not high, which limits the application of the method. Summary of the invention

[0004] In order to solve the above problems, the purpose of the present invention is to provide a method for analyzing thioadamantane compounds in crude oil and determining the oil source. The method uses atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry to analyze the element information and structural information of thioadamantane in crude oil, and determines the oil source through the isotope information of thioadamantane obtained at the same time.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A method for analyzing thioadamantane compounds in crude oil and determining the oil source, the method comprising:

[0007] (1) Analyzing and detecting the crude oil to be tested by atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry to determine the molecular formula and molecular structure of thioadamantane in the crude oil;

[0008] (2) Detection of stable isotopes of thioadamantanes in crude oil using atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry 32 S and 34 The signal intensity of S is compared with that of SF6 gas to obtain the sulfur isotope ratio δ, which is then compared with the isotope data of sulfate in known source rocks to determine the source of the crude oil.

[0009] Among them, the sulfur isotope ratio δ = ‰ × (34Rsample / 34RSF6)-1, 34Rsample is the sulfur isotope ratio of crude oil. 34 S signal strength and 32 S signal strength ratio; 34RSF6 is SF6 34 S signal strength and 32 S signal strength ratio.

[0010] Preferably, in step (1), atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry is used to analyze and detect the crude oil to be tested, and the specific process is as follows: the crude oil to be tested is dissolved in a solvent to prepare a crude oil solution, and the crude oil solution is injected into an atmospheric pressure chemical ionization source; the molecular formula of thioadamantane is determined by the mass number of molecular ions, and the molecular structure of thioadamantane is determined by the mass number of fragment ions obtained by high-energy collision dissociation.

[0011] Preferably, the molecular ion mass number is selected from 154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n;

[0012] Among them, the molecular ion mass number is 154.081+14.015n as the mass number of one-cage thioadamantane, the molecular ion mass number is 206.112+14.015n as the mass number of two-cage thioadamantane, the molecular ion mass number is 258.144+14.015n as the mass number of three-cage thioadamantane, the molecular ion mass number is 310.175+14.015n as the mass number of four-cage thioadamantane, and the molecular ion mass number is 362.206+14.015n as the mass number of five-cage thioadamantane;

[0013] n is 0 or a positive integer, 14.015 is the mass number of CH2; the mass numbers of the fragment ions obtained by high-energy collision dissociation are selected from 91, 105, 79, 81, 119, 131, 145 and 159.

[0014] Preferably, the solvent in step (1) is one or more of carbon disulfide, carbon tetrachloride, isooctane and dimethyl sulfoxide.

[0015] Preferably, the solvent in step (1) is one or both of carbon disulfide and isooctane. When the solvent is carbon disulfide and isooctane, the volume ratio of carbon disulfide to isooctane is (1:9) to (9:1).

[0016] Preferably, the concentration of the crude oil solution in step (1) is 0.01 to 2.0 mg / mL.

[0017] Preferably, the concentration of the crude oil solution in step (1) is 0.05-0.8 mg / mL.

[0018] Preferably, the conditions for atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry detection in step (1) are set as follows:

[0019] The crude oil solution was injected into the atmospheric pressure chemical ionization source at a rate of 1 to 100 μL / min;

[0020] The sheath gas of the atmospheric pressure chemical ionization source is N2 or He, with a flow rate of 1 to 100 Arb, the auxiliary gas is N2 or He containing 0.1 to 0.5 vol% SF6 gas, with a flow rate of 1 to 25 Arb, and the back-blowing gas is N2 or He, with a flow rate of 0.01 to 1.0 Arb;

[0021] The discharge current of the atmospheric pressure chemical ionization source was set to 1-40 μA, the ion transfer capillary temperature was set to 200-400°C, and the evaporator temperature was set to 200-400°C;

[0022] The ion trap high-resolution mass spectrometer was set to full scan from 50.0 to 800.0 m / z, with a resolution of 100000 to 700000; the mass numbers of molecular ion peaks extracted by the quadrupole of the ion trap high-resolution mass spectrometer were 154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n, where n was 0 or a positive integer, and the number of injected ions was 1×10 5 ~9×10 5 The maximum injection time is 10 to 1000 ms, the number of micro scans is 1 to 10, and the energy of high-energy collision dissociation is 5 to 50 eV.

[0023] Preferably, the crude oil solution is injected into the atmospheric pressure chemical ionization source at a rate of 5 to 50 μL / minn.

[0024] Preferably, the sheath gas of the atmospheric pressure chemical ionization source is N2, and the flow rate is 5-20Arb; the auxiliary gas of the atmospheric pressure chemical ionization source is N2 containing 0.1-0.3 vol% SF6 gas, and the flow rate is 2-10Arb; the backblowing gas of the atmospheric pressure chemical ionization source is N2, and the flow rate is 0.05-0.2Arb.

[0025] Preferably, the discharge current of the atmospheric pressure chemical ionization source is set to 2-10 μA, the ion transfer capillary temperature is set to 300-400°C, and the evaporator temperature is set to 300-400°C.

[0026] Preferably, the ion trap high-resolution mass spectrometer is set to a full scan from 60.0 to 600.0 m / z with a resolution of 300,000 to 600,000.

[0027] Preferably, the number of injected ions extracted by the quadrupole of the ion trap high-resolution mass spectrometer is 3×10 5 ~8×10 5 The maximum injection time is 50-200 ms, the number of micro-scans is 2-5, and the energy of high-energy collision dissociation is 10-35 eV.

[0028] The analysis principle of the method of the present invention:

[0029] When determining the source of crude oil, the first choice is to find a biomarker that is highly thermally stable and not susceptible to biodegradation. Figure 1 ), this special chemical structure has extremely high thermodynamic stability and biological stability, so it is selected as a biomarker for determining the source of oil. However, how to analyze thioadamantanes in crude oil and how to efficiently and accurately determine the sulfur isotopes of thioadamantanes is an unresolved problem. The present invention provides a method for analyzing thioadamantanes, and provides a method for determining the source of oil using the sulfur isotope data of thioadamantanes. Since the sulfur in the sulfur-containing compounds (thioadamantanes) in crude oil comes from sulfates in source rocks and is transferred to sulfur-containing compounds through thermal reduction of sulfates, the sulfur isotopes of crude oil thioadamantanes should be similar to the sulfur isotopes of sulfates in the source rocks corresponding to the crude oil. If the two are not similar, the crude oil should not come from the source rock, and the greater the difference in the values ​​between the two, the worse the corresponding relationship.

[0030] The beneficial effects of the present invention are:

[0031] The method provided by the present invention can realize the analysis of trace (≤100ppm) thioadamantane compounds in crude oil by using a small amount of crude oil (≤0.1g), and determine the oil source by using the sulfur isotope information recorded by the compounds, with high sensitivity and good repeatability, avoiding the need for manual multiple separation and enrichment experimental steps. It takes ≤1 hour to complete the analysis of one crude oil, which is convenient for realizing high-throughput screening and can serve on-site production in a timely manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1The molecular structures of thioadamantane compounds are shown in Figure 2. (a) is a monothioadamantane (2-thiatricyclo[3.3.1.1^{3,7}]decane), (b) is a dithioadamantane (3-thiapentacyclo[7.3.1.1^{4,12}.0^{2,7}.0^{6,11}]tetradecane), (c) is a trithioadamantane (16-thiaheptacyclo[7.7.1.1^{3,15}.0^{1,12}.0^{2,7}.0^{4,13}.0^{6,11}]octadecane), and (d) is a monothioadamantane (2-thiatricyclo[3.3.1.1^{3,7}]decane). ) is a tetrathioadamantane (7-thianonacyclo[11.7.1.1^{6,18}.0^{1,16}.0^{2,11}.0^{3,8}.0^{4,19}.0^{8,17}.0^{10,15}]docosane), (e) is a pentathioadamantane (4-thiaundecacyclo[9.9.1.1^{1,5}.1^{3,7}.1^{3,15}.1^{9,13}.1^{11,19}.0^{2,17}.0^{7,21}.0^{12,17}.0^{13,25}]hexacosane);

[0033] Figure 2 is the fragment ion mass spectrum of Example 1;

[0034] Figure 3 is the fragment ion mass spectrum of Example 2;

[0035] Figure 4 This is the fragment ion mass spectrum of Example 3. Specific embodiments

[0036] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Example 1

[0038] This embodiment provides a method for analyzing thioadamantane compounds in crude oil and determining the oil source, which comprises the following steps:

[0039] (1) Luntan 1 crude oil was dissolved in carbon disulfide to prepare a solution with a concentration of 0.2 mg / mL, and injected into an atmospheric pressure chemical ionization source at a rate of 20 μL / min. The sheath gas of the atmospheric pressure chemical ionization source was N2 with a flow rate of 20 Arb, the auxiliary gas was N2 containing 0.1 vol% SF6 gas with a flow rate of 5 Arb, and the backflush gas was N2 with a flow rate of 0.5 Arb. The discharge current was set to 10 μA, the ion transfer capillary temperature was set to 350°C, and the evaporator temperature was set to 400°C. The ion trap high-resolution mass spectrometer was set to a full scan from 50.0 to 800.0 m / z with a resolution of 500,000. The mass numbers of the molecular ion peaks extracted by the quadrupole of the ion trap high-resolution mass spectrometer are (154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n, n is 0 or a positive integer), and the number of injected ions extracted is 5×10 5 The maximum injection time is 200ms, the number of microscans is 5, and the energy of high-energy collision dissociation is 25eV. The fragment ion mass spectrum (such as Figure 2 shown).

[0040] The molecular formula of thioadamantane was determined to be C by the molecular ion mass number (362.206) and the fragment ion mass numbers (91, 105, 79, 81, 119, 131, 145 and 159). 25 H 30 S (element information) and molecular structure are unsubstituted penta-cage thioadamantane, the structural formula is as follows Figure 1 As shown in (e).

[0041] (2) Stable isotopes of penta-thioadamantane measured by atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry 32 S and 34The signal intensity of S was measured and compared with SF6 gas to obtain the isotope ratio. The monomer δ of the thioadamantane compound in Luntan 1 crude oil was calculated to be +36.8~39.2, with an average value of +37.4. The isotope distribution range of sulfate in the Cambrian source rock of the basin where the crude oil is located is 33.5~38.0, with an average value of +35.5, and the isotope distribution range of sulfate in the Ordovician source rock of the basin where the crude oil is located is 21.1~24.6, with an average value of +23.6. Obviously, the monomer sulfur isotope of the thioadamantane compound in Luntan 1 crude oil is closer to the isotope of sulfate in the Cambrian source rock. Since the thioadamantane compound is formed by ethyl noradamantane compound and sulfate in the source rock through sulfate thermal cracking, the monomer sulfur isotope information of the thioadamantane compound indicates the original information of its source rock. Moreover, the thioadamantane compound has a cage structure with stable physical and chemical properties, and it is not found to be disturbed by other secondary effects. Therefore, it is judged that the Luntan 1 crude oil comes from the Cambrian source rocks in this basin.

[0042] Example 2

[0043] This embodiment provides a method for analyzing thioadamantane compounds in crude oil and determining the oil source, which comprises the following steps:

[0044] (1) Gaotan 1 crude oil was dissolved in dimethyl sulfoxide to prepare a solution with a concentration of 2.0 mg / mL, and injected into the atmospheric pressure chemical ionization source at a rate of 100 μL / min. The sheath gas of the atmospheric pressure chemical ionization source was He with a flow rate of 95 Arb, the auxiliary gas was He containing 0.5 vol% SF6 gas with a flow rate of 24 Arb, and the backflush gas was He with a flow rate of 1.0 Arb. The discharge current was set to 36 μA, the ion transfer capillary temperature was set to 400°C, and the evaporator temperature was set to 400°C. The ion trap high-resolution mass spectrometer was set to a full scan from 50.0 to 800.0 m / z with a resolution of 680,000. The mass numbers of the molecular ion peaks extracted by the quadrupole of the ion trap high-resolution mass spectrometer are (154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n, n is 0 or a positive integer), and the number of injected ions extracted is 9×10 5 The maximum injection time was 1000 ms, the number of microscans was 10, and the energy of high-energy collision dissociation was 20 eV. The molecular ion mass number (310.175) and the fragment ion mass number (91, 105, 79, 81, 119, 131, 145 and 159) (see Figure 3 ) together determine the molecular formula of thioadamantane to be C 21 H 26S (element information) and the molecular structure are unsubstituted tetracage thioadamantane ( Figure 1 (d)

[0045] (2) Stable isotopes of different thioadamantanes were measured by atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry 32 S and 34 The signal intensity of S was measured and compared with SF6 gas to obtain the isotope ratio. The monomer δ of the thioadamantane compound in Gaotan 1 crude oil was calculated to be +26.2-29.8, with an average value of +27.3. The isotope distribution range of sulfate in the Jurassic source rocks of the basin where the crude oil is located is 23.3-27.1, with an average value of +25.4, the isotope distribution range of sulfate in the Triassic source rocks of the basin where the crude oil is located is 31.2-33.9, with an average value of +32.5, and the isotope distribution range of sulfate in the Permian source rocks of the basin where the crude oil is located is 35.0-38.8, with an average value of +36.6. Obviously, the monomer sulfur isotope of thioadamantane compounds in Gaotan 1 crude oil is closer to the isotope of sulfate in Jurassic source rocks. Since thioadamantane compounds are formed by ethyl noradamantane compounds and sulfate in source rocks through sulfate thermal cracking, the monomer sulfur isotope information of thioadamantane compounds indicates the original information of its source rocks. Moreover, thioadamantane compounds have a cage-like structure with stable physical and chemical properties, and it is not found that they will be disturbed by other secondary effects. Therefore, it is judged that Gaotan 1 crude oil comes from the Jurassic source rocks of the basin.

[0046] Example 3

[0047] This embodiment provides a method for analyzing thioadamantane compounds in crude oil and determining the oil source, which comprises the following steps:

[0048] (1) Dissolve the Manshen 3 crude oil in isooctane to prepare a solution with a concentration of 0.05 mg / mL, and inject it into the atmospheric pressure chemical ionization source at a rate of 20 μL / min. The sheath gas of the atmospheric pressure chemical ionization source is N2 with a flow rate of 20 Arb, the auxiliary gas is N2 containing 0.1 vol% SF6 gas with a flow rate of 5 Arb, and the backflush gas is N2 with a flow rate of 0.5 Arb. The discharge current is set to 10 μA, the ion transfer capillary temperature is set to 350°C, and the evaporator temperature is set to 400°C. The ion trap high-resolution mass spectrometer is set to a full scan from 50.0 to 800.0 m / z with a resolution of 500,000. The mass numbers of the molecular ion peaks extracted by the quadrupole of the ion trap high-resolution mass spectrometer are (154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n, n is 0 or a positive integer), and the number of injected ions extracted is 5×10 5The maximum injection time is 200ms, the number of microscans is 5, and the energy of high-energy collision dissociation is 25eV. The fragment ion mass spectrum (such as Figure 4 shown).

[0049] The molecular formula of thioadamantane was determined to be C by the molecular ion mass number (258.144) and the fragment ion mass numbers (91, 105, 79, 81, 119, 131, 145 and 159). 17 H 22 S (element information) and molecular structure are unsubstituted tris-cage thioadamantane, the structural formula is as follows Figure 1 As shown in (c).

[0050] (2) Stable isotopes of penta-thioadamantane measured by atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry 32 S and 34 The signal intensity of S was measured and compared with SF6 gas to obtain the isotope ratio. The monomer δ of the thioadamantane compound in Manshen 3 crude oil was calculated to be +35.4~37.9, with an average value of +36.6. The isotope distribution range of sulfate in the Cambrian source rock of the basin where the crude oil is located is 33.5~38.0, with an average value of +35.5, and the isotope distribution range of sulfate in the Ordovician source rock of the basin where the crude oil is located is 21.1~24.6, with an average value of +23.6. Obviously, the monomer sulfur isotope of the thioadamantane compound in Manshen 3 crude oil is closer to the isotope of sulfate in the Cambrian source rock. Since the thioadamantane compound is formed by ethyl noradamantane compound and sulfate in the source rock through sulfate thermal cracking, the monomer sulfur isotope information of the thioadamantane compound indicates the original information of its source rock. Moreover, the thioadamantane compound has a cage structure with stable physical and chemical properties, and it is not found that it will be disturbed by other secondary effects. Therefore, it is judged that the Manshen 3 crude oil comes from the Cambrian source rocks in this basin.

[0051] Comparative Example 1

[0052] Luntan 1 crude oil was dissolved in a mixed solvent of toluene and methanol (volume ratio 1:1) to prepare a solution with a concentration of 0.2 mg / mL, which was injected into the atmospheric pressure chemical ionization source at a rate of 20 μL / min. The sheath gas of the atmospheric pressure chemical ionization source was N2 with a flow rate of 20 Arb, the auxiliary gas was N2 containing 0.1 vol% SF6 gas with a flow rate of 5 Arb, and the backflush gas was N2 with a flow rate of 0.5 Arb. The discharge current was set to 10 μA, the ion transfer capillary temperature was set to 350 ° C, and the evaporator temperature was set to 400 ° C. The ion trap high-resolution mass spectrometer was set to a full scan from 50.0 to 800.0 m / z with a resolution of 500000. The mass numbers of the molecular ion peaks extracted by the quadrupole of the ion trap high-resolution mass spectrometer are (154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n, n is 0 or a positive integer), and the number of injected ions extracted is 5×10 5 The maximum injection time was 200 ms, the number of microscans was 5, and the energy for high-energy collisional dissociation was 25 eV. No thioadamantanes were detected.

[0053] Comparative Example 2

[0054] Gaotan 1 crude oil was dissolved in n-octane to prepare a solution with a concentration of 10.0 mg / mL, and injected into the atmospheric pressure chemical ionization source at a rate of 100 μL / min. The sheath gas of the atmospheric pressure chemical ionization source was He with a flow rate of 95 Arb, the auxiliary gas was He containing 0.5 vol% SF6 gas with a flow rate of 24 Arb, and the backblowing gas was He with a flow rate of 1.0 Arb. The discharge current was set to 36 μA, the ion transfer capillary temperature was set to 400 ° C, and the evaporator temperature was set to 400 ° C. The ion trap high-resolution mass spectrometer was set to a full scan from 50.0 to 800.0 m / z with a resolution of 680000. The mass numbers of the molecular ion peaks extracted by the quadrupole of the ion trap high-resolution mass spectrometer are (154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015nn is 0 or a positive integer), and the number of injected ions extracted is 9×10 5 The maximum injection time was 1000 ms, the number of microscans was 10, and the energy for high-energy collisional dissociation was 20 eV. No thioadamantanes were detected.

[0055] From the comparison between the embodiment and the comparative example, it can be seen that:

[0056] When carbon disulfide, dimethyl sulfoxide, and isooctane are used as solvents, thioadamantane compounds can be detected; when a mixed solvent of toluene and methanol (volume ratio 1:1) or n-octane is used as solvent, thioadamantane compounds cannot be detected.

[0057] In addition, it should be noted that the method according to the present invention can also be inferred to the detection of other caged thioadamantanes with similar structures.

[0058] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for analyzing thioadamantane compounds in crude oil and determining the oil source, characterized in that: The method includes: (1) Analyzing and detecting the crude oil solution to be tested by atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry to determine the molecular formula and molecular structure of thioadamantane in the crude oil; (2) Detection of stable isotopes of thioadamantanes in crude oil using atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry 32 S and 34 The signal intensity of S is compared with that of SF6 gas to obtain the sulfur isotope ratio δ, which is then compared with the isotope data of sulfate in known source rocks to determine the source of the crude oil. Among them, the sulfur isotope ratio δ = ‰ × (34Rsample / 34RSF6)-1, 34Rsample is the sulfur isotope ratio of crude oil. 34 S signal strength and 32 S signal strength ratio; 34RSF6 is SF6 34 S signal strength and 32 S signal strength ratio; where, The mass of the crude oil to be tested is ≤0.1 g; the solvent of the crude oil solution is one or more of carbon disulfide, carbon tetrachloride, isooctane, and dimethyl sulfoxide.

2. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 1, characterized in that: In step (1), atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry is used to analyze and detect the crude oil to be tested. The specific process is as follows: injecting the crude oil solution to be tested into the atmospheric pressure chemical ionization source; determining the molecular formula of thioadamantane by the mass number of molecular ions, and determining the molecular structure of thioadamantane by the mass number of fragment ions obtained by high-energy collision dissociation.

3. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 2, characterized in that: The molecular ion mass number is selected from 154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n; Among them, the molecular ion mass number is 154.081+14.015n as the mass number of one-cage thioadamantane, the molecular ion mass number is 206.112+14.015n as the mass number of two-cage thioadamantane, the molecular ion mass number is 258.144+14.015n as the mass number of three-cage thioadamantane, the molecular ion mass number is 310.175+14.015n as the mass number of four-cage thioadamantane, and the molecular ion mass number is 362.206+14.015n as the mass number of five-cage thioadamantane; n is 0 or a positive integer, 14.015 is the mass number of CH2; the mass numbers of the fragment ions obtained by high-energy collision dissociation are selected from 91, 105, 79, 81, 119, 131, 145 and 159.

4. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 1, characterized in that: The solvent in step (1) is one or both of carbon disulfide and isooctane. When the solvent is carbon disulfide and isooctane, the volume ratio of carbon disulfide to isooctane is (1:9) to (9:1).

5. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 2, characterized in that: The concentration of the crude oil solution in step (1) is 0.01 to 2.0 mg / mL.

6. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 5, characterized in that: The concentration of the crude oil solution in step (1) is 0.05-0.8 mg / mL.

7. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 2, characterized in that: The conditions for atmospheric pressure chemical ionization source-ion trap high-resolution mass spectrometry detection in step (1) are set as follows: The crude oil solution was injected into the atmospheric pressure chemical ionization source at a rate of 1 to 100 μL / min; The sheath gas of the atmospheric pressure chemical ionization source is N2 or He, with a flow rate of 1 to 100 Arb, the auxiliary gas is N2 or He containing 0.1 to 0.5 vol% SF6 gas, with a flow rate of 1 to 25 Arb, and the back-blowing gas is N2 or He, with a flow rate of 0.01 to 1.0 Arb; The discharge current of the atmospheric pressure chemical ionization source was set to 1-40 μA, the ion transfer capillary temperature was set to 200-400°C, and the evaporator temperature was set to 200-400°C; The ion trap high-resolution mass spectrometer was set to full scan from 50.0 to 800.0 m / z, with a resolution of 100000 to 700000; the mass numbers of molecular ion peaks extracted by the quadrupole of the ion trap high-resolution mass spectrometer were 154.081+14.015n, 206.112+14.015n, 258.144+14.015n, 310.175+14.015n or 362.206+14.015n, where n was 0 or a positive integer, and the number of injected ions was 1×10 5 ~9×10 5 The maximum injection time is 10 to 1000 ms, the number of micro scans is 1 to 10, and the energy of high-energy collision dissociation is 5 to 50 eV.

8. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 7, characterized in that: The crude oil solution is injected into the atmospheric pressure chemical ionization source at a speed of 5 to 50 μL / minn.

9. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 7, characterized in that: The sheath gas of the atmospheric pressure chemical ionization source is N2 with a flow rate of 5 to 20 Arb; the auxiliary gas of the atmospheric pressure chemical ionization source is N2 containing 0.1 to 0.3 vol% SF6 gas with a flow rate of 2 to 10 Arb; the backwash gas of the atmospheric pressure chemical ionization source is N2 with a flow rate of 0.05 to 0.2 Arb.

10. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 7, characterized in that: The discharge current of the atmospheric pressure chemical ionization source is set to 2-10 μA, the temperature of the ion transfer capillary is set to 300-400°C, and the temperature of the evaporator is set to 300-400°C.

11. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 7, characterized in that: The ion trap high-resolution mass spectrometer is set to full scan from 60.0 to 600.0 m / z, with a resolution of 300,000 to 600,000.

12. The method for analyzing thioadamantane compounds in crude oil and determining the oil source according to claim 7, characterized in that: The number of injected ions extracted by the quadrupole of the ion trap high-resolution mass spectrometer is 3×10 5 ~8×10 5 The maximum injection time is 50-200 ms, the number of micro-scans is 2-5, and the energy of high-energy collision dissociation is 10-35 eV.

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