Diesel Component Analysis Method and Device Based on Comprehensive Two-Dimensional Gas Chromatography-Mass Spectrometer

Abstract

The present invention relates to the technical field of petrochemical analysis and detection, and is a method and device for analyzing diesel components based on a comprehensive two-dimensional gas chromatography-mass spectrometer. The method includes: preprocessing a diesel sample; using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to test the preprocessed diesel sample to obtain a test spectrum; performing integration processing and characteristic region division processing on the test spectrum to obtain the substance information corresponding to each component contained in the diesel sample to be analyzed. The above characteristic region division processing is to perform preliminary segmentation and refined segmentation processing according to the characteristic differences corresponding to each component. The data processing logic in the present invention can be constructed as a script or an application and automatically executed by an electronic device, effectively reducing the interference factors in manual analysis and the recognition errors in the analysis by different people, realizing the rapid, comprehensive and quantitative analysis of complex components in diesel, improving the analysis efficiency, and reducing the analysis cost and manual analysis errors.

Description

Technical Field

[0001] The invention relates to the technical field of petrochemical analysis and detection, and is a diesel component analysis method and device based on a comprehensive two-dimensional gas chromatography-mass spectrometer. Background Art

[0002] In the field of petrochemicals, component analysis of crude oil and various oil products obtained from crude oil refining is an important part of determining the refining effect and subsequently improving the refining process. Diesel is an important petroleum product that is widely used in transportation, industry, agriculture and other fields. The quality and performance of diesel are closely related to its chemical composition, so it is very necessary to accurately, quickly and comprehensively analyze the various components in diesel.

[0003] Common diesel analysis methods include: SH / T 0606 "Determination of hydrocarbon composition in intermediate fractions (mass spectrometry)", ASTMD8368 gas chromatography-vacuum ultraviolet absorption spectroscopy (GC-VUV), etc. The SH / T 0606 method (GC-MS) separates the sample into saturated hydrocarbons and aromatic hydrocarbons through a solid phase extraction column, and then enters the mass spectrometer for analysis after separation by a chromatographic column, and can obtain the content of chain alkanes, cycloalkanes, monocyclic aromatic hydrocarbons, dicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons in the diesel fraction. The diesel composition obtained by GC-MS is more detailed, but it is necessary to use a solvent to separate the saturated hydrocarbons and aromatic hydrocarbon components obtained from the diesel sample for mass spectrometry determination. There are many human interference factors in this process, and it cannot provide information on the carbon number distribution of diesel hydrocarbons. The GC-VUV method can detect the content of saturated hydrocarbons, monocyclic aromatic hydrocarbons, bicyclic aromatic hydrocarbons, and tricyclic and higher aromatic hydrocarbons in diesel. It can also obtain the carbon number distribution information of diesel. Direct sampling without pretreatment and separation makes the detection faster and more convenient, but it cannot make further distinctions for saturated hydrocarbons (such as alkanes and cycloalkanes).

[0004] Therefore, it is necessary to study a new diesel component analysis method and device to solve the above problems. Summary of the invention

[0005] The present invention provides a diesel component analysis method and device based on a comprehensive two-dimensional gas chromatography-mass spectrometer, which overcomes the shortcomings of the above-mentioned prior art and can effectively solve the problems of many interference factors in human analysis, large recognition errors and low analysis efficiency in the existing diesel component analysis.

[0006] One of the technical solutions of the present invention is achieved by the following measures: a diesel component analysis method based on a comprehensive two-dimensional gas chromatography-mass spectrometer, comprising:

[0007] Pre-treating the diesel sample to obtain a pre-treated diesel sample;

[0008] The pretreated diesel sample is tested by using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed;

[0009] The test spectrum of the diesel sample to be analyzed is subjected to integration processing and feature region division processing to obtain the material information corresponding to each component contained in the diesel sample to be analyzed; wherein, the feature region division processing is to perform preliminary segmentation according to the feature differences corresponding to each component and continue to perform refined segmentation processing on the basis of the preliminary segmentation.

[0010] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions:

[0011] The above-mentioned test spectrum of the diesel sample to be analyzed is subjected to integration processing and characteristic region division processing to obtain the material information corresponding to each component contained in the diesel sample to be analyzed, including:

[0012] The test spectrum of the diesel sample to be analyzed is integrated according to all mass spectrum fragments, and matched with the known material spectrum library to obtain each preliminary matching substance;

[0013] Perform preliminary segmentation of the feature region according to the differences of each preliminary matching substance to obtain multiple preliminary segmentation regions; wherein the feature differences between the multiple preliminary segmentation regions exceed a set value and are regarded as different components, and there is a situation in which multiple material fragments have similar features in the same preliminary segmentation region;

[0014] For each preliminary segmentation area, the material fragments are finely divided according to the refined feature differences, and the boundaries of the preliminary segmentation area are dynamically adjusted to obtain multiple target segmentation areas;

[0015] According to the material fragments in the multiple target segmentation areas, the material information corresponding to each component contained in the diesel sample to be analyzed is determined.

[0016] The above preliminary segmentation areas include:

[0017] Alkane region, monocyclic alkane region, dicyclic alkane region, tricyclic and above alkane region, monocyclic aromatic hydrocarbon region, dicyclic aromatic hydrocarbon region, tricyclic and above aromatic hydrocarbon region;

[0018] Among them, in the following preliminary segmentation areas: alkane area, monocyclic alkane area, tricyclic and above aromatic hydrocarbon area, there are multiple material fragments with similar characteristics in the same preliminary segmentation area, and multiple sub-areas are obtained through refined division, and the alkane area is refined into: alkane sub-area and olefin sub-area, the monocyclic alkane area is refined into: pentacyclic alkane sub-area and hexacyclic alkane sub-area, and the tricyclic and above aromatic hydrocarbon area is refined into: tricyclic aromatic hydrocarbon sub-area, tetracyclic aromatic hydrocarbon sub-area and pentacyclic aromatic hydrocarbon sub-area.

[0019] The diesel samples are a set of diesel sample collections, which include: a plurality of control diesel samples for optimizing test conditions and diesel samples to be analyzed for component analysis;

[0020] Among them, the pretreated diesel sample is tested using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed, including:

[0021] Using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer, multiple reference diesel samples are tested according to corresponding multiple test conditions to obtain test spectra of the multiple reference diesel samples;

[0022] According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions under which the component separation effect meets the preset requirements are determined;

[0023] The diesel sample to be analyzed is tested according to the target test conditions using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed.

[0024] The injection concentrations of the above-mentioned multiple control diesel samples are different. The control diesel samples of the same injection concentration are divided into multiple parts and tested multiple times using different comparison conditions, wherein the comparison conditions include differences in at least one of the following conditions: modulation cycle, temperature control parameters, carrier gas flow rate, and the temperature control parameters include: initial temperature of the two-dimensional chromatographic column, heating rate, injection port temperature, modulation compensation temperature, and ionization source temperature;

[0025] According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions whose component separation effects meet the preset requirements are determined, including:

[0026] Comparing the first test spectra of a plurality of control diesel samples under the same comparison conditions and different injection concentrations, determining the injection concentration corresponding to the test spectrum having a signal-to-noise ratio of mass spectrum information in the first test spectrum higher than a first set threshold and a resolution higher than a second set threshold as the target injection concentration;

[0027] Comparing the second test spectra obtained by using different comparison conditions at the target injection concentration for multiple control diesel samples, determining the condition corresponding to the test spectrum in the second test spectrum whose component separation effect meets the preset requirements and whose detection sensitivity is higher than the third set threshold as the target condition;

[0028] Based on the target injection concentration and target conditions, target test conditions are generated.

[0029] The above-mentioned pretreatment includes dilution pretreatment of the diesel sample, wherein during the dilution pretreatment, the sample is diluted according to a volume ratio, and the dilution multiple is 20 to 100 times.

[0030] When the diesel sample is diluted and pretreated, dichloromethane is used as the dilution solvent;

[0031] After the diesel sample is diluted, ultrasonic dispersion treatment is performed to make the diesel sample fully dissolved and evenly dispersed;

[0032] Alternatively, after diluting the diesel sample, filtering treatment is performed to remove moisture and mechanical impurities, and the diesel sample after filtering treatment is subjected to ultrasonic dispersion treatment to make the diesel sample fully dissolved and evenly dispersed.

[0033] The above method also includes:

[0034] The material information corresponding to each component is classified and summarized to obtain the carbon number distribution information corresponding to different components;

[0035] Among them, the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

[0036] The above-mentioned comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer comprises: a first-dimensional chromatographic column, a second-dimensional chromatographic column, a modulator, a time-of-flight mass spectrometer and a data processing module, wherein the first-dimensional chromatographic column adopts a non-polar or weakly polar chromatographic column, and the second-dimensional chromatographic column adopts a medium-polarity chromatographic column;

[0037] The test conditions for the diesel samples included:

[0038] The initial temperature of the first-dimension chromatographic column is 30°C to 60°C, maintained for 1 min to 3 min, increased to 280°C to 310°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the initial temperature of the second-dimension chromatographic column is 5°C to 10°C higher than the initial temperature of the first-dimension chromatographic column, maintained for 1 min to 3 min, increased to 290°C to 315°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the carrier gas is high-purity helium, the flow rate is 1 mL / min to 1.2 mL / min, the injection volume is 0.1 μL to 0.2 μL, and the injection port temperature is 280°C to 310°C;

[0039] The modulation time of the modulator is 3s to 4s, the cold modulation time is 0.9s to 1.2s, the hot modulation time is 1.5s to 1.8s, and the modulation compensation temperature is 10℃ to 15℃;

[0040] The scanning range of the time-of-flight mass spectrometer is set to 5u to 1000u, where u represents atomic mass unit, which can also be expressed as amu, the electron bombardment ionization source is set to an electron energy of 70eV to 80eV, and the source temperature of the ionization source is set to 250°C to 270°C;

[0041] The following steps are performed based on the data processing module:

[0042] Perform integration processing and feature area division processing on the test spectrum of the diesel sample to be analyzed to obtain the material information corresponding to each component contained in the diesel sample to be analyzed;

[0043] The material information corresponding to each component is classified and summarized to obtain the carbon number distribution information corresponding to different components.

[0044] The second technical solution of the present invention is achieved by the following measures: a device for applying a diesel component analysis method based on a comprehensive two-dimensional gas chromatography-mass spectrometer, comprising:

[0045] A data acquisition module, used for acquiring a test spectrum of the diesel sample to be analyzed obtained by testing the diesel sample to be analyzed, wherein the test spectrum of the diesel sample to be analyzed is obtained by testing the pretreated diesel sample using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer;

[0046] The data processing module is used to perform integration processing and feature area division processing on the test spectrum of the diesel sample to be analyzed, so as to obtain the material information corresponding to each component contained in the diesel sample to be analyzed; wherein the feature area division processing is to perform preliminary segmentation according to the feature differences corresponding to each component and continue to perform refined segmentation processing on the basis of the preliminary segmentation.

[0047] The following is a further optimization and / or improvement of the second technical solution of the above invention:

[0048] The above data processing module includes:

[0049] The integration processing submodule is used to integrate the test spectrum of the diesel sample to be analyzed according to all mass spectrum fragments and match it with the known material spectrum library to obtain various preliminary matching substances;

[0050] The segmentation submodule is used to perform preliminary segmentation of the feature region according to the differences of each preliminary matching substance, and obtain multiple preliminary segmentation regions; wherein the feature differences between the multiple preliminary segmentation regions exceed the set value and are regarded as different components, and there is a situation where multiple material fragments have similar features in the same preliminary segmentation region;

[0051] An adjustment submodule is used to perform a fine division of material fragments according to the refined feature differences for each preliminary segmentation area and dynamically adjust the boundaries of the preliminary segmentation area to obtain multiple target segmentation areas;

[0052] The classification submodule is used to determine the material information corresponding to each component contained in the diesel sample to be analyzed based on the material fragments in the multiple target segmentation areas.

[0053] The above-mentioned device also includes:

[0054] The classification and summary module is used to classify and summarize the material information corresponding to each component to obtain the carbon number distribution information corresponding to different components;

[0055] Among them, the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

[0056] The above preliminary segmentation areas include:

[0057] Alkane region, monocyclic alkane region, dicyclic alkane region, tricyclic and above alkane region, monocyclic aromatic hydrocarbon region, dicyclic aromatic hydrocarbon region, tricyclic and above aromatic hydrocarbon region;

[0058] Among them, in the following preliminary segmentation areas: alkane area, monocyclic alkane area, tricyclic and above aromatic hydrocarbon area, there are multiple material fragments with similar characteristics in the same preliminary segmentation area, and multiple sub-areas are obtained through refined division; among them, the alkane area is refined into: alkane sub-area and olefin sub-area; the monocyclic alkane area is refined into: pentacyclic alkane sub-area and hexacyclic alkane sub-area; the tricyclic and above aromatic hydrocarbon area is refined into: tricyclic aromatic hydrocarbon sub-area, tetracyclic aromatic hydrocarbon sub-area and pentacyclic aromatic hydrocarbon sub-area.

[0059] The diesel samples are a set of diesel sample collections, which include: a plurality of control diesel samples for optimizing test conditions and diesel samples to be analyzed for component analysis;

[0060] The test spectrum is obtained in the following way:

[0061] Using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer, multiple reference diesel samples are tested according to corresponding multiple test conditions to obtain test spectra of the multiple reference diesel samples;

[0062] According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions under which the component separation effect meets the preset requirements are determined;

[0063] The diesel sample to be analyzed is tested according to the target test conditions using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed.

[0064] The injection concentrations of the above-mentioned multiple control diesel samples are different. The control diesel samples of the same injection concentration are divided into multiple parts and tested multiple times using different comparison conditions; the comparison conditions include differences in at least one of the following conditions: modulation cycle, temperature control parameters, carrier gas flow rate; the temperature control parameters include: initial temperature of the two-dimensional chromatographic column, heating rate, injection port temperature, modulation compensation temperature and ionization source temperature;

[0065] According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions whose component separation effects meet the preset requirements are determined, including:

[0066] Comparing the first test spectra of a plurality of control diesel samples under the same comparison conditions and different injection concentrations, determining the injection concentration corresponding to the test spectrum having a signal-to-noise ratio of mass spectrum information in the first test spectrum higher than a first set threshold and a resolution higher than a second set threshold as the target injection concentration;

[0067] Comparing the second test spectra obtained by using different comparison conditions at the target injection concentration for multiple control diesel samples, determining the condition corresponding to the test spectrum in the second test spectrum whose component separation effect meets the preset requirements and whose detection sensitivity is higher than the third set threshold as the target condition;

[0068] Based on the target injection concentration and target conditions, target test conditions are generated.

[0069] The above-mentioned comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer comprises: a first-dimensional chromatographic column, a second-dimensional chromatographic column, a modulator and a time-of-flight mass spectrometer;

[0070] The first dimension chromatographic column is a non-polar or weakly polar chromatographic column; the second dimension chromatographic column is a medium polar chromatographic column;

[0071] The test conditions for the diesel samples included:

[0072] The initial temperature of the first-dimension chromatographic column is 30°C to 60°C, maintained for 1 min to 3 min, increased to 280°C to 310°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the initial temperature of the second-dimension chromatographic column is 5°C to 10°C higher than the initial temperature of the first-dimension chromatographic column, maintained for 1 min to 3 min, increased to 290°C to 315°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the carrier gas is high-purity helium, the flow rate is 1 mL / min to 1.2 mL / min, the injection volume is 0.1 μL to 0.2 μL, and the injection port temperature is 280°C to 310°C;

[0073] The modulation time of the modulator is 3s to 4s, the cold modulation time is 0.9s to 1.2s, the hot modulation time is 1.5s to 1.8s, and the modulation compensation temperature is 10℃ to 15℃;

[0074] The scan range of the time-of-flight mass spectrometer is set to 5u to 1000u, where u represents atomic mass unit, which can also be expressed as amu, the electron bombardment ionization source is set to an electron energy of 70eV to 80eV, and the source temperature of the ionization source is set to 250°C to 270°C.

[0075] The above-mentioned pretreatment includes dilution pretreatment; wherein, the dilution is performed according to a volume ratio, and the dilution multiple is between 20 times and 100 times.

[0076] When the diesel sample is diluted and pretreated, dichloromethane is used as the dilution solvent;

[0077] After the diesel sample is diluted, ultrasonic dispersion treatment is performed to make it fully dissolved and evenly dispersed;

[0078] Alternatively, after diluting the diesel sample, filtering treatment is performed to remove moisture and mechanical impurities, and the diesel sample after filtering treatment is subjected to ultrasonic dispersion treatment to fully dissolve and evenly disperse the diesel sample.

[0079] The above also includes:

[0080] The classification and summary module is used to classify and summarize the material information corresponding to each component to obtain the carbon number distribution information corresponding to different components, wherein the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

[0081] The above-mentioned device and the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer are different equipment, and data can be transmitted between the device and the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer;

[0082] Alternatively, the device is integrated into a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer.

[0083] The data processing logic in the present invention can be constructed as a script or application and automatically executed by electronic equipment, which effectively reduces interference factors in human analysis and recognition errors in different human analyses, realizes rapid, comprehensive and quantitative analysis of complex components in diesel, improves analysis efficiency, and reduces analysis costs and human analysis errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0085] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0086] Attached Figure 1 This is a flow chart of a diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to an embodiment of the present invention;

[0087] Attached Figure 2 This is a flow chart of a diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to another embodiment of the present invention;

[0088] Attached Figure 3 is a detailed implementation flow chart of step S120 of an embodiment of the present invention;

[0089] Attached Figure 4 is a detailed implementation flow chart of step S130 of an embodiment of the present invention;

[0090] Attached Figure 5 This is a schematic diagram of a spectrum of the test spectrum of the diesel sample to be analyzed after integration processing according to all mass spectrum fragments according to an embodiment of the present invention;

[0091] Attached Figure 6 It is a schematic diagram of spectrum results after preliminary division and refined division are performed on the spectrum after integration processing and the region boundaries are adjusted according to one embodiment of the present invention;

[0092] Attached Figure 7 A schematic diagram of determining the material information corresponding to each component contained in the diesel sample to be analyzed and deriving the Chinese result according to the material fragments in the multiple target segmentation areas according to an embodiment of the present invention;

[0093] Attached Figure 8 The structure block diagram of the device for applying the diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to an embodiment of the present invention. DETAILED DESCRIPTION

[0094] 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.

[0095] The first exemplary embodiment of the present invention provides a diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry.

[0096] Figure 1 The flowchart of a diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry in one embodiment of the present invention is schematically shown.

[0097] Reference Figure 1 As shown, the diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry provided by the embodiment of the present invention includes the following steps: S110, S120 and S130.

[0098] In some embodiments, the above step S130 can be written as a program execution script and run in a data processing module. The above data processing module can be integrated into a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer; or the device where the above data processing module is located is different from the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer. The data processing module can obtain a test spectrum of the diesel sample to be analyzed from the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer and perform component analysis.

[0099] Step S110, pre-processing the diesel sample.

[0100] Step S120, using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to test the pretreated diesel sample to obtain a test spectrum.

[0101] Step S130, performing integration processing and feature area division processing on the test spectrum of the diesel sample to be analyzed, and obtaining the material information corresponding to each component contained in the above-mentioned diesel sample to be analyzed; wherein, the above-mentioned feature area division processing is to perform preliminary segmentation according to the feature differences corresponding to each component and continue to perform refined segmentation processing on the basis of the preliminary segmentation.

[0102] Based on the above steps S110 to S130, the pretreated diesel sample is tested by using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum; the test spectrum of the diesel sample to be analyzed is integrated and characterized by region division to obtain material information corresponding to each component contained in the above diesel sample to be analyzed; since the above characteristic region division process is to perform preliminary segmentation according to the characteristic differences corresponding to each component and then continue to perform refined segmentation on the basis of the preliminary segmentation, it is possible to effectively separate and detect different components in diesel, including the contents of normal alkanes, isoalkanes, one-ring cycloalkanes, two-ring cycloalkanes, three-ring and above cycloalkanes, monocyclic aromatic hydrocarbons, bicyclic aromatic hydrocarbons, three-ring and above aromatic hydrocarbons, and the like, thereby improving the accuracy and reliability of diesel quality analysis and control; the method uses a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer (GC×GC-TOF The method is based on the MS (Multiple Spectrophotometer) technology, and by setting the material classification logic of preliminary segmentation and refined segmentation, it can improve the accuracy of the composition and content analysis of diesel molecules. Compared with the manual analysis method of manually exporting test spectrum information in the prior art, the data processing logic set by this method can be constructed as a script or application to be automatically executed by electronic equipment, which effectively reduces the interference factors in human analysis and the recognition errors of different people's analysis, and realizes the rapid, comprehensive and quantitative analysis of complex components in diesel, which can improve the analysis efficiency, thereby reducing the analysis cost and human analysis errors. Moreover, this method has good repeatability and reproducibility, low detection limit, wide linear range, and is suitable for the analysis of diesel from different sources and qualities. The above-mentioned diesel component analysis results can accurately guide refining enterprises to optimize the diesel conversion process, so as to improve the utilization rate of raw materials or reduce refining costs, etc., to achieve cost reduction and efficiency improvement.

[0103] Compared with the conventional gas chromatography-mass spectrometry scheme used in the prior art to analyze chemical composition, these schemes can only identify one-dimensional spectra and obtain corresponding substances according to the number of peaks. It is still necessary to manually count the contents of different types of substances in the later stage, which is a large workload, and the separation effect is not very good. One peak may contain many substances, and there is an overlapping phenomenon. The embodiment of the present invention uses two chromatographic columns for two-dimensional superposition separation, that is, it can effectively perform secondary separation on the substances in a peak in the original one-dimensional graph, identify more substances, and effectively increase the accuracy of component analysis by setting an original data processing logic; this data processing logic can be constructed as a script to automatically run based on electronic equipment, so as to more accurately identify the category of the substance based on the ion fragment information of the substance in the test spectrum, reduce the unstable factors and analysis errors of manual analysis, and also effectively improve the processing efficiency of analyzing and processing a large number of ion fragments.

[0104] Figure 2The flowchart of a diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to another embodiment of the present invention is schematically shown.

[0105] Reference Figure 2 As shown, in addition to steps S110 to S130, the method further includes the following steps: S210, classifying and summarizing the material information corresponding to the above components to obtain carbon number distribution information corresponding to different components.

[0106] Among them, the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

[0107] The following is a detailed description of each of the above steps.

[0108] In one embodiment, in the above step S110, the above pretreatment includes but is not limited to: dilution pretreatment; wherein the dilution is performed according to a volume ratio, and the dilution multiple is 20 to 100 times. The dilution multiple means: the ratio of the concentration of the diluted solution to the concentration of the original solution, and the concentration here adopts the volume concentration.

[0109] The sample concentration will affect the signal-to-noise ratio and resolution of the mass spectrometer. If the sample concentration is too high, the ion source will be saturated, and the signal intensity will no longer increase linearly with the increase in concentration. At the same time, the collision between ions will increase, reducing the resolution of the mass spectrometer. If the sample concentration is too low, the signal intensity will be too weak, the target substance cannot be effectively detected, and the signal-to-noise ratio will also be reduced. Therefore, when the full two-dimensional gas chromatography-mass spectrometer is injected, according to the effect of component analysis of diesel, the embodiment of the present invention sets the dilution factor to 20 to 100 times, so that the sample concentration can ensure the accuracy and sensitivity of the mass spectrometer.

[0110] In some embodiments, after the diesel sample is diluted, ultrasonic dispersion treatment is performed to fully dissolve and evenly disperse it; or, in other embodiments, after the diesel sample is diluted, filtration treatment is performed to remove moisture and mechanical impurities; and the diesel sample after filtration treatment is subjected to ultrasonic dispersion treatment to fully dissolve and evenly disperse it.

[0111] For example, add dichloromethane to dilute the diesel sample 20 to 200 times, and then use ultrasonic treatment to make the diesel sample fully uniform and dissolved. Then, use a pipette to take 1 mL to 2 mL of the pretreated diesel sample (in a diluted solution state), put it into a chromatographic vial and send it to the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer for testing.

[0112] Figure 3The detailed implementation flow chart of step S120 in one embodiment of the present invention is schematically shown.

[0113] In some embodiments, a plurality of control diesel samples are tested first to optimize the test conditions, and then the diesel samples to be analyzed are tested using the optimized test conditions.

[0114] In this embodiment, the diesel samples are a group of diesel sample sets, and the diesel sample set includes: a plurality of control diesel samples for optimizing test conditions and a diesel sample to be analyzed for component analysis.

[0115] Reference Figure 3 As shown, in the above step S120, the pretreated diesel sample is tested using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum, including the following steps: S310, S320 and S330.

[0116] In step S310, a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer is used to test the plurality of reference diesel samples according to the corresponding plurality of test conditions to obtain test spectra of the plurality of reference diesel samples.

[0117] In step S320, according to the test conditions corresponding to the plurality of control diesel samples and the effect differences of the test spectra, a target test condition whose component separation effect meets the preset requirements is determined.

[0118] In some embodiments, the injection concentrations of the above-mentioned multiple control diesel samples are different, and the control diesel sample with the same injection concentration is divided into multiple parts and tested multiple times using different comparison conditions.

[0119] The above-mentioned comparison conditions include differences in at least one of the following conditions: modulation period, temperature control parameters, and carrier gas flow rate; the above-mentioned temperature control parameters include: initial temperature of the two-dimensional chromatographic column, heating rate, injection port temperature, modulation compensation temperature, and temperature of the ionization source.

[0120] Taking the modulation period as an example, the choice of the modulation period depends on the peak width on the first-dimensional chromatographic column and the separation ability on the second-dimensional chromatographic column. It needs to be optimized according to the sample complexity and the characteristics of the target compound to achieve the best separation effect and detection sensitivity. According to the test results of different modulation periods, the appropriate modulation period is selected to make the component distribution more complete.

[0121] The setting of temperature control parameters is mainly determined according to the boiling points of various substances in diesel components. It is better when the temperature rises slowly, but it is not good if it is too slow. It can be optimized and adjusted according to the effect of the test spectrum.

[0122] In the above step S320, according to the test conditions corresponding to the above multiple control diesel samples and the effect differences of the test spectra, determining the target test conditions whose component separation effect meets the preset requirements includes:

[0123] Comparing the first test spectra of the plurality of control diesel samples under the same comparison conditions and different injection concentrations, determining the injection concentration corresponding to the test spectrum having a signal-to-noise ratio of mass spectrum information in the first test spectrum higher than a first set threshold and a resolution higher than a second set threshold as the target injection concentration;

[0124] Comparing the second test spectra obtained by using different comparison conditions at the target injection concentration for the plurality of control diesel samples, determining the condition corresponding to the test spectrum in the second test spectrum whose component separation effect meets the preset requirements and whose detection sensitivity is higher than the third set threshold as the target condition;

[0125] According to the above target injection concentration and the above target conditions, target test conditions are generated.

[0126] In some embodiments, the first test spectrum or the second test spectrum may be an original spectrum output by a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer, or may be a spectrum after being integrated in step S130.

[0127] Comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry can simultaneously obtain the retention time and mass spectrum information of the chromatographic peak after testing the pretreated diesel samples.

[0128] In step S330, the diesel sample to be analyzed is tested according to the target test conditions using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed.

[0129] In the embodiment including the above steps S310 to S330, the test conditions are optimized by setting up multiple control diesel samples for testing first, so as to obtain test conditions that can make the test spectrum have a high signal-to-noise ratio, high resolution, good component separation effect and high detection sensitivity. This helps to match more and more accurate substances within a certain molecular weight range in the known material spectrum library in the subsequent diesel component analysis process, thereby helping to improve the accuracy of the diesel sample component analysis.

[0130] In some embodiments, the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer comprises: a first-dimensional chromatographic column, a second-dimensional chromatographic column, a modulator, a time-of-flight mass spectrometer, and a data processing module.

[0131] The data processing module performs the following steps: integrating and dividing the test spectrum of the diesel sample to be analyzed to obtain the material information corresponding to each component contained in the diesel sample to be analyzed (corresponding to step S130). In some embodiments, the data processing module may further perform the following steps: classifying and summarizing the material information corresponding to each component to obtain the carbon number distribution information corresponding to different components (step S210 described later).

[0132] Wherein, the first-dimension chromatographic column is a non-polar or weakly polar chromatographic column; and the second-dimension chromatographic column is a medium-polar chromatographic column.

[0133] The test conditions for the diesel samples include: the initial temperature of the first-dimension chromatographic column is 30°C to 60°C, maintained for 1 min to 3 min, increased to 280°C to 310°C at a rate of 2°C / min to 4°C / min, and maintained for 5 min to 10 min; the initial temperature of the second-dimension chromatographic column is 5°C to 10°C higher than the initial temperature of the first-dimension chromatographic column, maintained for 1 min to 3 min, increased to 290°C to 315°C at a rate of 2°C / min to 4°C / min, and maintained for 5 min to 10 min; the carrier gas is high-purity helium, with a flow rate of 1 mL / min to 1 .2mL / min; the injection volume is 0.1μL (microliter) to 0.2μL; the injection port temperature is 280℃ to 310℃; the modulation time of the above modulator is 3s to 4s, the cold modulation time is 0.9s to 1.2s, and the hot modulation time is 1.5s to 1.8s; the modulation compensation temperature is 10℃ to 15℃; the scanning range of the above time-of-flight mass spectrometer is set to 5u to 1000u, where u represents atomic mass unit, which can also be expressed as amu; the electron bombardment ionization source sets the electron energy to 70eV to 80eV, and the source temperature of the ionization source is set to 250℃ to 270℃.

[0134] For example, in one embodiment, the first-dimensional chromatographic column is a DB-Petro chromatographic column, 50m×0.2mm inner diameter, and 0.5μm film thickness; the second-dimensional chromatographic column is an Rxi-17sil MS medium polarity chromatographic column, 1.390m×0.15mm inner diameter, and 0.15μm film thickness. The modulation time of the modulator is 4s, the cold modulation time is 1.2s, the hot modulation time is 1.8s, and the modulation compensation temperature is 15°C. The time-of-flight mass spectrometer is set to a scanning range of 5u to 1000u, the electron bombardment ionization source is set to an electron energy of 70eV, and the source temperature is set to 250°C. The carrier gas is high-purity helium with a flow rate of 1mL / min; the injection volume is 0.1μL; and the injection port temperature is 280°C.

[0135] The temperature program of the column oven was set as follows: the initial temperature of the first-dimension chromatographic column was 60°C, maintained for 1 min, increased to 310°C at a rate of 2°C / min, and maintained for 5 min; the initial temperature of the second-dimension chromatographic column was 65°C, maintained for 1 min, increased to 315°C at a rate of 2°C / min, and maintained for 5 min.

[0136] Figure 4 The detailed implementation flow chart of step S130 in one embodiment of the present invention is schematically shown.

[0137] In some embodiments, reference Figure 4 As shown, in the above step S130, integration processing and feature area division processing are performed on the test spectrum of the diesel sample to be analyzed to obtain material information corresponding to each component contained in the above diesel sample to be analyzed, including the following steps: S410, S420, S430 and S440.

[0138] In step S410, the test spectrum of the diesel sample to be analyzed is integrated according to all mass spectrum fragments and matched with a known material spectrum library to obtain various preliminary matching substances.

[0139] Figure 5 The schematic diagram of the spectrum after the test spectrum of the diesel sample to be analyzed is integrated according to all mass spectrum fragments in one embodiment of the present invention is schematically shown.

[0140] The test spectrum obtained for the diesel sample to be analyzed is the original spectrum, which can only obtain the corresponding light spot (substance response) information. The darker the light spot brightness, the higher the relative content of the substance represented, but the specific substance information cannot be obtained. By integrating the original spectrum, it is helpful to match each response signal with the ion fragment information to match the substance corresponding to each signal. The spectrum obtained after integrating the test spectrum according to all mass spectrum fragments is referred to Figure 5 As shown, each black dot represents a substance; due to the large amount of data, it is difficult to manually screen each substance, so in an embodiment of the present invention, the spectrum information is further processed by using a data matching tool in the full two-dimensional software. Based on the data matching tool, the result obtained after integration can be matched with the known material spectrum library, and the material information corresponding to the result after integration is determined according to the similarity of the match, which is the preliminary matching material. The processing logic of this data matching tool is: using the mass spectrum to match the material information, the mass spectrometer determines the mass-to-charge ratio (m / z) of the sample compound after ionization, mass analysis and detection, and the ions are separated according to their mass-to-charge ratio (m / z), and the separated ions generate signals through the detector. The data matching tool here is to match and compare the mass spectrum with the existing data spectrum library to identify the compound.

[0141] In this embodiment, the integration conditions used are: the baseline adopts the established mode, the baseline compensation is 0.5, and the curve smoothing adopts the automatic mode; GCxGC parameters: the one-dimensional peak width is 8s, the two-dimensional matching value is 650, and the two-dimensional peak width is 0.1s. The signal-to-noise ratio is 100, and the maximum number of matching peaks is 10000; the number of peaks in the library search is 10, the collection method is all mass spectrum fragments, and the molecular weight search range is 35-600. The m / z (the ratio of the mass m of the ion to the charge z, m / z is the mass-to-charge ratio) search range is 0-500. By setting this integration condition, the regional range of each component of diesel can be more effectively and accurately screened in the subsequent segmentation process according to characteristic differences.

[0142] In step S420, the feature region is preliminarily segmented according to the differences between the various preliminary matching materials to obtain multiple preliminary segmented regions; wherein the feature differences between the multiple preliminary segmented regions exceed the set value and are regarded as different components, and there is a situation where multiple material fragments have similar features in the same preliminary segmented region.

[0143] In steps S420 and S430, the distribution positions of different types of substances in the two-dimensional spectrum are determined, and preliminary area division is performed; in some embodiments, the execution logic corresponding to steps S420 and S430 can be constructed as a corresponding execution script.

[0144] The components of diesel samples identified in the full two-dimensional data include alkanes, cycloalkanes, monocyclic aromatic hydrocarbons, dicyclic aromatic hydrocarbons, and tricyclic aromatic hydrocarbons; these different components show a tile-like structure in the two-dimensional spectrum and have their own distribution areas and relatively obvious boundaries. Since the fragments of alkanes, alkenes, and cycloalkanes are similar, their molecular information is relatively concentrated, so they will exist in the same preliminary segmentation area. Therefore, according to the differences and distribution characteristics of each preliminary matching substance, it is preliminarily divided into different preliminary segmentation areas: alkane area, monocyclic alkane area, dicyclic alkane area, tricyclic and above alkane area, monocyclic aromatic hydrocarbon area, dicyclic aromatic hydrocarbon area, tricyclic and above aromatic hydrocarbon area, etc.

[0145] Among the following preliminary segmented regions: alkane region, monocyclic alkane region, tricyclic and above aromatic hydrocarbon region, there are cases where multiple material fragments have similar characteristics in the same preliminary segmented region. Therefore, it is necessary to obtain multiple sub-regions by performing refined segmentation in step S430.

[0146] In step S430, for each preliminary segmentation region, the material fragments are finely divided according to the refined feature difference and the boundary of the preliminary segmentation region is dynamically adjusted to obtain a plurality of target segmentation regions.

[0147] In some embodiments, in order to narrow the scope of the search library, for the same preliminary segmentation area, the combination information of the pre-contaminated mixed material fragments that are easy to be mixed can be written in advance in the electronic device. This combination information is stored in the classification and analysis database. The data volume of this classification and analysis database is much smaller than the known material spectrum library. At the same time, the ion fragment information corresponding to the easily mixed mixed materials is integrated to facilitate the improvement of the recognition efficiency of easily mixed materials during the analysis process. In some embodiments, the above combination information defines which different substances correspond to the mixed material fragments, the material fragment characteristics corresponding to different substances, and the material fragment characteristic differences; by searching for each preliminary segmentation area and screening and matching with the above combination information of mixed material fragments, the material fragments can be refined according to the refined characteristic differences. In this way, the boundaries of the preliminary segmentation area can be adjusted according to the results of the refined division to obtain multiple adjusted target segmentation areas.

[0148] Since there are some areas where material identification is inaccurate or mixed during the preliminary division process, the material fragments are divided finely according to the refined feature differences, and the boundaries of the preliminary segmentation area are dynamically adjusted according to the results of the refined division, so that all ion fragments corresponding to the same substance are divided into the same area as much as possible, and the ion fragments belonging to other substances are excluded.

[0149] Among them, the alkane region is finely divided into: alkane sub-region and olefin sub-region; the monocyclic alkane region is finely divided into: pentacyclic alkane sub-region and hexacyclic alkane sub-region; the three-ring and above aromatic hydrocarbon region is finely divided into: three-ring aromatic hydrocarbon sub-region, four-ring aromatic hydrocarbon sub-region and five-ring aromatic hydrocarbon sub-region.

[0150] Figure 6 The schematic diagram of the spectrum result after the spectrum after the integral processing is preliminarily divided and refined and the region boundaries are adjusted according to an embodiment of the present invention is schematically shown. Figure 6 As shown, the spectrum of the diesel sample to be analyzed presents multiple target segmentation areas, and the material fragments of the same substance are marked with the same color.

[0151] In step S440, material information corresponding to each component contained in the diesel sample to be analyzed is determined according to the material fragments in the plurality of target segmented regions.

[0152] Table 1 schematically shows that according to one embodiment of the present invention, the material information corresponding to each component contained in the diesel sample to be analyzed is determined based on the material fragments in the multiple target segmentation areas and the English results are derived as shown in Table 1; Figure 7The schematic diagram schematically shows a schematic diagram of determining the material information corresponding to each component contained in the diesel sample to be analyzed and exporting the Chinese result according to the material fragments in multiple target segmentation areas according to an embodiment of the present invention.

[0153] Table 1

[0154] .

[0155] Refer to Table 1 and Figure 7 As shown, the substance name (Name, expressed in English here), two-dimensional retention time (RT, Retention Time, the unit is seconds), peak area (Area), peak area percentage (Area %), CAS identification number, classification (classification) and molecular formula (Formula) corresponding to each component are illustrated. It should be noted that the peak area can represent the intensity of the substance response and can be used as an expression of the content in the classification. Since the content is in the form of percentage, the peak area percentage can be completely equivalent to the content. In order to better understand the statistical classification method below, "peak area percentage" and "content" are both expressed as "area".

[0156] In mass spectrometry, substances with the same chemical formula can be analyzed into multiple structures, but their fragmentation patterns and mass-to-charge ratio distributions in the mass spectra are different. The mass spectrometer can accurately distinguish these differences through mass spectrometry and ionization methods, and can analyze and identify multiple isomers in the sample in detail. Compared with traditional methods, this has the advantage of greatly improving the accuracy and efficiency of identification, making the analysis of complex samples more intuitive and reliable.

[0157] In an embodiment including steps S410 to S440, the test spectrum of the diesel sample to be analyzed is integrated according to all mass spectrum fragments and matched with a library of known material spectra to obtain preliminary matching substances; the characteristic regions are preliminarily segmented according to the differences between the preliminary matching substances, and refined segmentation processing is continued on the basis of the preliminary segmentation and the boundaries of the divided regions are dynamically adjusted; thereby improving the degree of refinement and accuracy of the composition of multiple target segmented regions and the corresponding component substances.

[0158] In some embodiments, after obtaining the material information (material composition and content) corresponding to each component, it also includes: classifying and summarizing the material information corresponding to the above-mentioned components to obtain the carbon number distribution information corresponding to different components. For example, the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes can be classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes. The classification condition can be a specific attribute of the data, such as normal alkanes; it can also be a certain range of data, such as all compounds with a carbon number of 10. The summary can be summation, counting, average value, etc.

[0159] This classification and aggregation process can be based on the user's classification requirement instructions (for example, classification and aggregation of alkanes with a carbon number of 1) to call the corresponding function or algorithm for corresponding processing. For example, the component analysis results obtained after executing the analysis method provided by the embodiment of the present invention on a diesel sample are shown in Table 2, where the content is expressed in mass percentage.

[0160] Table 2

[0161] .

[0162] At the same time, in order to verify the test stability and reliability of the method provided in the embodiment of the present invention, a comparative analysis was performed on the component analysis results of the two batches of diesel samples. The comparison of the test conditions of the two batches of diesel is shown in Table 3, and the comparison results of the component analysis obtained after the two batches of diesel are shown in Table 4.

[0163] Table 3

[0164] .

[0165] Table 4 Comparison of component analysis results of two batches of diesel samples

[0166] .

[0167] From the comparison data in Table 3 and Table 4, it can be seen that the two batches of diesel samples were tested under the same test conditions of the same comprehensive two-dimensional gas chromatography-mass spectrometer, and the deviations of the component analysis results were relatively small, with the maximum deviation being less than 1%, indicating that the data stability was good and the method had good reliability.

[0168] For ordinary gas chromatography-mass spectrometry, only one-dimensional spectra can be identified, and the corresponding substances can be obtained according to the number of peaks. It is still necessary to manually count the contents of different types of substances in the later stage, which is a large workload, and the separation effect is not very good. One peak may contain many substances, and there is an overlapping phenomenon. In the embodiment of the present invention, the analysis and testing of diesel components are carried out by using a full two-dimensional gas chromatography-mass spectrometer, and the refined processing logic for data analysis is added at the same time; on the one hand, based on the advantages of the full two-dimensional gas chromatography-mass spectrometer, the two chromatographic columns perform hierarchical material separation in the two-dimensional direction, which can effectively separate the substances in a peak in the original one-dimensional graph for a second time, identify more substances, and increase accuracy; at the same time, the refined processing logic for data analysis set by the method can be constructed as a script or application automatically executed by an electronic device, effectively reducing the interference factors in the manual analysis and the recognition errors of different people's analysis, and realizing the rapid, comprehensive and quantitative analysis of complex components in diesel, which can improve the analysis efficiency, thereby reducing the analysis cost and manual analysis errors. Moreover, this method has good repeatability and reproducibility, low detection limit, wide linear range, and is suitable for the analysis of diesel from different sources and qualities. The component analysis results of the above diesel can accurately guide refining companies to optimize the diesel conversion process, so as to improve raw material utilization or reduce refining costs, etc., to achieve cost reduction and efficiency improvement.

[0169] A second exemplary embodiment of the present invention provides an apparatus for applying a diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry.

[0170] Figure 8 The structure block diagram of the device for applying the diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to an embodiment of the present invention is schematically shown.

[0171] Reference Figure 8 As shown, the device 800 for applying the diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry provided in this embodiment includes: a data acquisition module 810 and a data processing module 820 .

[0172] The data acquisition module 810 is used to acquire a test spectrum obtained by testing the diesel sample to be analyzed; wherein the test spectrum is obtained by testing the pretreated diesel sample using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer.

[0173] The above-mentioned data processing module 820 is used to perform integration processing and characteristic area division processing on the test spectrum of the diesel sample to be analyzed, so as to obtain the material information corresponding to each component contained in the above-mentioned diesel sample to be analyzed; wherein, the above-mentioned characteristic area division processing is to perform preliminary segmentation according to the characteristic differences corresponding to each component and continue to perform refined segmentation processing on the basis of the preliminary segmentation.

[0174] In some embodiments, the data processing module 820 includes: an integration processing submodule 821 , a segmentation submodule 822 , an adjustment submodule 823 and a classification submodule 824 .

[0175] The above-mentioned integral processing submodule 821 is used to integrate the test spectrum of the above-mentioned diesel sample to be analyzed according to all mass spectrum fragments and match it with the known material spectrum library to obtain various preliminary matching substances.

[0176] The segmentation submodule 822 is used to perform preliminary segmentation of feature regions according to the differences between the preliminary matching materials to obtain multiple preliminary segmentation regions; wherein the feature differences between the multiple preliminary segmentation regions exceed the set value and are regarded as different components, and there are situations in which the features of multiple material fragments are similar in the same preliminary segmentation region.

[0177] The adjustment submodule 823 is used to perform a fine division of material fragments according to the fine feature difference for each preliminary segmentation region and dynamically adjust the boundary of the preliminary segmentation region to obtain a plurality of target segmentation regions.

[0178] The classification submodule 824 is used to determine the material information corresponding to each component contained in the diesel sample to be analyzed according to the material fragments in the multiple target segmentation areas.

[0179] In some embodiments, the above-mentioned device and the above-mentioned comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer are different equipment, and data can be transmitted between the above-mentioned device and the above-mentioned comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer; or, the above-mentioned device is integrated in the above-mentioned comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer.

[0180] In some embodiments, the above-mentioned device also includes: a classification and summary module.

[0181] The classification and summary module is used to classify and summarize the material information corresponding to each of the above components to obtain the carbon number distribution information corresponding to different components. Among them, the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

[0182] For more details and beneficial effects of this embodiment, please refer to the relevant description of the first embodiment, which will not be repeated here.

[0183] Any number of the functional modules included in the diesel component analysis device can be combined into one module, or any one of the modules can be split into multiple modules. Alternatively, at least part of the functions of one or more of these modules can be combined with at least part of the functions of other modules and implemented in one module. At least one of the functional modules included in the diesel component analysis device can be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), a system on a chip, a system on a substrate, a system on a package, an application-specific integrated circuit (ASIC), or can be implemented by hardware or firmware such as any other reasonable way of integrating or packaging the circuit, or implemented in any one of the three implementation methods of software, hardware and firmware or in any appropriate combination of any of them. Alternatively, at least one of the functional modules included in the diesel component analysis device can be at least partially implemented as a computer program module, and when the computer program module is run, the corresponding function can be executed.

[0184] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0185] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry, characterized in that: include: Pre-treating the diesel sample to obtain a pre-treated diesel sample; The pretreated diesel sample is tested by using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed; The test spectrum of the diesel sample to be analyzed is subjected to integration processing and feature region division processing to obtain the material information corresponding to each component contained in the diesel sample to be analyzed; wherein, the feature region division processing is to perform preliminary segmentation according to the feature difference corresponding to each component and continue to perform refined segmentation processing on the basis of the preliminary segmentation. For the preliminary segmentation area obtained by the preliminary segmentation, there is a situation where multiple material fragments have similar features in the same preliminary segmentation area. The refined segmentation processing includes: for each preliminary segmentation area, performing refined division of material fragments according to the refined feature difference, and dynamically adjusting the boundary of the preliminary segmentation area to obtain multiple target segmentation areas; wherein, the classification and analysis database stores the combination information of the mixed material fragments that are easy to be mixed, and the combination information is used to define which different substances correspond to the mixed material fragments, the material fragment features corresponding to the different substances, and the material fragment feature differences; by searching in the classification and analysis database for each preliminary segmentation area and screening and matching with the combination information, the refined division of material fragments is realized, and the boundary of the preliminary segmentation area is adjusted according to the result of the refined division to obtain the adjusted multiple target segmentation areas.

2. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 1 is characterized in that: The test spectrum of the diesel sample to be analyzed is integrated and characterized by region division to obtain the material information corresponding to each component contained in the diesel sample to be analyzed, including: The test spectrum of the diesel sample to be analyzed is integrated according to all mass spectrum fragments, and matched with the known material spectrum library to obtain each preliminary matching substance; Performing preliminary segmentation of the characteristic regions according to the differences of the preliminary matching substances to obtain a plurality of preliminary segmented regions; wherein the characteristic differences between the plurality of preliminary segmented regions exceed a set value and are regarded as different components; For each preliminary segmented area, a refined segmentation process is performed to obtain multiple target segmented areas; According to the material fragments in the multiple target segmentation areas, the material information corresponding to each component contained in the diesel sample to be analyzed is determined.

3. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 2 is characterized in that: The initial segmentation areas include: Alkane region, monocyclic alkane region, dicyclic alkane region, tricyclic and above alkane region, monocyclic aromatic hydrocarbon region, dicyclic aromatic hydrocarbon region, tricyclic and above aromatic hydrocarbon region; Among them, in the following preliminary segmentation areas: alkane area, monocyclic alkane area, tricyclic and above aromatic hydrocarbon area, there are multiple material fragments with similar characteristics in the same preliminary segmentation area, and multiple sub-areas are obtained through refined division, and the alkane area is refined into: alkane sub-area and olefin sub-area, the monocyclic alkane area is refined into: pentacyclic alkane sub-area and hexacyclic alkane sub-area, and the tricyclic and above aromatic hydrocarbon area is refined into: tricyclic aromatic hydrocarbon sub-area, tetracyclic aromatic hydrocarbon sub-area and pentacyclic aromatic hydrocarbon sub-area.

4. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 1, 2 or 3, characterized in that: The diesel sample is a set of diesel sample collections, and the diesel sample collections include: a plurality of control diesel samples for optimizing test conditions and diesel samples to be analyzed for component analysis; Among them, the pretreated diesel sample is tested using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed, including: Using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer, multiple reference diesel samples are tested according to corresponding multiple test conditions to obtain test spectra of the multiple reference diesel samples; According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions under which the component separation effect meets the preset requirements are determined; The diesel sample to be analyzed is tested according to the target test conditions using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed.

5. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 4 is characterized in that: The injection concentrations of the multiple control diesel samples are different. The control diesel samples of the same injection concentration are divided into multiple parts and tested multiple times using different comparison conditions, wherein the comparison conditions include differences in at least one of the following conditions: modulation cycle, temperature control parameters, carrier gas flow rate, and the temperature control parameters include: initial temperature of the two-dimensional chromatographic column, heating rate, injection port temperature, modulation compensation temperature, and ionization source temperature; According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions whose component separation effects meet the preset requirements are determined, including: Comparing the first test spectra of a plurality of control diesel samples under the same comparison conditions and different injection concentrations, determining the injection concentration corresponding to the test spectrum having a signal-to-noise ratio of mass spectrum information in the first test spectrum higher than a first set threshold and a resolution higher than a second set threshold as the target injection concentration; Comparing the second test spectra obtained by using different comparison conditions at the target injection concentration for multiple control diesel samples, determining the condition corresponding to the test spectrum in the second test spectrum whose component separation effect meets the preset requirements and whose detection sensitivity is higher than the third set threshold as the target condition; Based on the target injection concentration and target conditions, target test conditions are generated.

6. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 1, 2, 3 or 5, characterized in that: The pretreatment includes dilution pretreatment of the diesel sample, wherein during the dilution pretreatment, the sample is diluted according to a volume ratio, and the dilution multiple is 20 to 100 times.

7. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 6 is characterized in that: When the diesel sample is diluted for pretreatment, dichloromethane is used as the dilution solvent; After the diesel sample is diluted, ultrasonic dispersion treatment is performed to make the diesel sample fully dissolved and evenly dispersed; Or / and, after diluting the diesel sample, filtering is performed to remove moisture and mechanical impurities, and the diesel sample after filtering is subjected to ultrasonic dispersion treatment to fully dissolve and evenly disperse the diesel sample.

8. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 1, 2, 3, 5 or 7, characterized in that: The method further comprises: The material information corresponding to each component is classified and summarized to obtain the carbon number distribution information corresponding to different components; Among them, the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

9. The diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to claim 8, characterized in that: The comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer comprises: a first-dimensional chromatographic column, a second-dimensional chromatographic column, a modulator, a time-of-flight mass spectrometer and a data processing module, wherein the first-dimensional chromatographic column is a non-polar or weakly polar chromatographic column, and the second-dimensional chromatographic column is a medium-polar chromatographic column; The test conditions for the diesel samples included: The initial temperature of the first-dimension chromatographic column is 30°C to 60°C, maintained for 1 min to 3 min, increased to 280°C to 310°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the initial temperature of the second-dimension chromatographic column is 5°C to 10°C higher than the initial temperature of the first-dimension chromatographic column, maintained for 1 min to 3 min, increased to 290°C to 315°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the carrier gas is high-purity helium, the flow rate is 1 mL / min to 1.2 mL / min, the injection volume is 0.1 μL to 0.2 μL, and the injection port temperature is 280°C to 310°C; The modulation time of the modulator is 3s to 4s, the cold modulation time is 0.9s to 1.2s, the hot modulation time is 1.5s to 1.8s, and the modulation compensation temperature is 10℃ to 15℃; The scanning range of the time-of-flight mass spectrometer is set to 5u to 1000u, where u represents atomic mass unit, which can also be expressed as amu, the electron bombardment ionization source is set to an electron energy of 70eV to 80eV, and the source temperature of the ionization source is set to 250°C to 270°C; The following steps are performed based on the data processing module: Perform integration processing and feature area division processing on the test spectrum of the diesel sample to be analyzed to obtain the material information corresponding to each component contained in the diesel sample to be analyzed; The material information corresponding to each component is classified and summarized to obtain the carbon number distribution information corresponding to different components.

10. A device using the diesel component analysis method based on comprehensive two-dimensional gas chromatography-mass spectrometry according to any one of claims 1 to 9, characterized in that: include: A data acquisition module, used for acquiring a test spectrum of the diesel sample to be analyzed obtained by testing the diesel sample to be analyzed, wherein the test spectrum of the diesel sample to be analyzed is obtained by testing the pretreated diesel sample using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer; The data processing module is used to perform integration processing and feature area division processing on the test spectrum of the diesel sample to be analyzed, so as to obtain the material information corresponding to each component contained in the diesel sample to be analyzed; wherein the feature area division processing is to perform preliminary segmentation according to the feature difference corresponding to each component and continue to perform fine segmentation processing on the basis of the preliminary segmentation. For the preliminary segmentation area obtained by the preliminary segmentation, there is a situation where the features of multiple material fragments are similar in the same preliminary segmentation area. The fine segmentation processing includes: for each preliminary segmentation area, performing fine division of material fragments according to the fine feature difference, and dynamically adjusting the boundary of the preliminary segmentation area to obtain multiple target segmentation areas; wherein the classification and analysis database stores the combination information of the mixed material fragments that are easy to be mixed, and the combination information is used to define which different substances correspond to the mixed material fragments, the material fragment features corresponding to the different substances, and the material fragment feature differences; by searching in the classification and analysis database for each preliminary segmentation area and screening and matching with the combination information, the fine division of material fragments is realized, and the boundary of the preliminary segmentation area is adjusted according to the result of the fine division to obtain the adjusted multiple target segmentation areas.

11. The device according to claim 10, characterized in that Data processing module, including: The integration processing submodule is used to integrate the test spectrum of the diesel sample to be analyzed according to all mass spectrum fragments and match it with the known material spectrum library to obtain various preliminary matching substances; A segmentation submodule is used to perform preliminary segmentation of the characteristic region according to the differences of each preliminary matching substance to obtain a plurality of preliminary segmented regions; wherein the characteristic differences between the plurality of preliminary segmented regions exceed a set value and are regarded as different components; The adjustment submodule is used to perform a refined segmentation process on each preliminary segmented region to obtain multiple target segmented regions; The classification submodule is used to determine the material information corresponding to each component contained in the diesel sample to be analyzed based on the material fragments in the multiple target segmentation areas.

12. The device according to claim 10 or 11, characterized in that The device also includes: The classification and summary module is used to classify and summarize the material information corresponding to each component to obtain the carbon number distribution information corresponding to different components; Among them, the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

13. The device according to claim 12, characterized in that The initial segmentation areas include: Alkane region, monocyclic alkane region, dicyclic alkane region, tricyclic and above alkane region, monocyclic aromatic hydrocarbon region, dicyclic aromatic hydrocarbon region, tricyclic and above aromatic hydrocarbon region; Among them, in the following preliminary segmentation areas: alkane area, monocyclic alkane area, tricyclic and above aromatic hydrocarbon area, there are multiple material fragments with similar characteristics in the same preliminary segmentation area, and multiple sub-areas are obtained through refined division; among them, the alkane area is refined into: alkane sub-area and olefin sub-area; the monocyclic alkane area is refined into: pentacyclic alkane sub-area and hexacyclic alkane sub-area; the tricyclic and above aromatic hydrocarbon area is refined into: tricyclic aromatic hydrocarbon sub-area, tetracyclic aromatic hydrocarbon sub-area and pentacyclic aromatic hydrocarbon sub-area.

14. The device according to claim 13, characterized in that The diesel sample is a set of diesel sample collections, and the diesel sample collections include: a plurality of control diesel samples for optimizing test conditions and diesel samples to be analyzed for component analysis; The test spectrum is obtained in the following way: Using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer, multiple reference diesel samples are tested according to corresponding multiple test conditions to obtain test spectra of the multiple reference diesel samples; According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions under which the component separation effect meets the preset requirements are determined; The diesel sample to be analyzed is tested according to the target test conditions using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to obtain a test spectrum of the diesel sample to be analyzed.

15. The device according to claim 14, characterized in that The injection concentrations of the multiple control diesel samples are different, and the control diesel samples of the same injection concentration are divided into multiple parts and tested multiple times using different comparison conditions; the comparison conditions include differences in at least one of the following conditions: modulation cycle, temperature control parameters, carrier gas flow rate; The temperature control parameters include: initial temperature of the two-dimensional chromatographic column, heating rate, injection port temperature, modulation compensation temperature and ionization source temperature; According to the differences in the test conditions and test spectra corresponding to multiple control diesel samples, the target test conditions whose component separation effects meet the preset requirements are determined, including: Comparing the first test spectra of a plurality of control diesel samples under the same comparison conditions and different injection concentrations, determining the injection concentration corresponding to the test spectrum having a signal-to-noise ratio of mass spectrum information in the first test spectrum higher than a first set threshold and a resolution higher than a second set threshold as the target injection concentration; Comparing the second test spectra obtained by using different comparison conditions at the target injection concentration for multiple control diesel samples, determining the condition corresponding to the test spectrum in the second test spectrum whose component separation effect meets the preset requirements and whose detection sensitivity is higher than the third set threshold as the target condition; Based on the target injection concentration and target conditions, target test conditions are generated.

16. The device according to claim 15, characterized in that The comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer comprises: a first-dimensional chromatographic column, a second-dimensional chromatographic column, a modulator and a time-of-flight mass spectrometer; The first dimension chromatographic column is a non-polar or weakly polar chromatographic column; the second dimension chromatographic column is a medium polar chromatographic column; The test conditions for the diesel samples included: The initial temperature of the first-dimension chromatographic column is 30°C to 60°C, maintained for 1 min to 3 min, increased to 280°C to 310°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the initial temperature of the second-dimension chromatographic column is 5°C to 10°C higher than the initial temperature of the first-dimension chromatographic column, maintained for 1 min to 3 min, increased to 290°C to 315°C at a rate of 2°C / min to 4°C / min, maintained for 5 min to 10 min, the carrier gas is high-purity helium, the flow rate is 1 mL / min to 1.2 mL / min, the injection volume is 0.1 μL to 0.2 μL, and the injection port temperature is 280°C to 310°C; The modulation time of the modulator is 3s to 4s, the cold modulation time is 0.9s to 1.2s, the hot modulation time is 1.5s to 1.8s, and the modulation compensation temperature is 10℃ to 15℃; The scan range of the time-of-flight mass spectrometer is set to 5u to 1000u, where u represents atomic mass unit, which can also be expressed as amu, the electron bombardment ionization source is set to an electron energy of 70eV to 80eV, and the source temperature of the ionization source is set to 250°C to 270°C.

17. The device according to claim 16, characterized in that The pretreatment includes dilution pretreatment; wherein, the dilution is performed according to a volume ratio, and the dilution multiple is between 20 and 100 times.

18. The device according to claim 17, characterized in that When the diesel sample is diluted for pretreatment, dichloromethane is used as the dilution solvent; After the diesel sample is diluted, ultrasonic dispersion treatment is performed to make it fully dissolved and evenly dispersed; Alternatively, after diluting the diesel sample, filtering treatment is performed to remove moisture and mechanical impurities, and the diesel sample after filtering treatment is subjected to ultrasonic dispersion treatment to fully dissolve and evenly disperse the diesel sample.

19. The device according to claim 18, characterized in that Also includes: The classification and summary module is used to classify and summarize the material information corresponding to each component to obtain the carbon number distribution information corresponding to different components, wherein the carbon number distribution of alkanes, cycloalkanes, aromatic hydrocarbons, normal alkanes and isoalkanes is classified and summarized to obtain the carbon number distribution information of alkanes, the carbon number distribution information of cycloalkanes, the carbon number distribution information of aromatic hydrocarbons, the carbon number distribution information of normal alkanes and the carbon number distribution information of isoalkanes.

20. The device according to claim 19, characterized in that The device and the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer are different devices, and data transmission can be performed between the device and the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer; Alternatively, the device is integrated into a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer.

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