Method for analyzing ozone-consuming substance in atmosphere by combining double columns with center cutting technology

Abstract

The invention belongs to the field of environmental monitoring, and particularly relates to a method for analyzing ozone depleting substances in atmosphere by combining double columns with a center cutting technology, ODS is separated by combining two capillary chromatographic columns with different polarities with the center cutting technology, and qualitative and quantitative analysis is carried out by entering a mass spectrum through a TwinLine system. By adopting the method disclosed by the invention, 36 ODS in the atmosphere can obtain good chromatographic peaks and separation degrees, the detection limit of the method disclosed by the invention can reach below 1pmol / mol, the measurement precision under the concentration level of pmol / mol can reach within 3%, and the problems that the concentration level of the ODS in the ambient air is low and the ODS is difficult to accurately monitor are solved.

Description

Technical Field

[0001] The present invention belongs to the field of environmental monitoring, and specifically relates to a method for analyzing ozone-depleting substances (ODS) in the atmosphere by using a double-column combined with a center-cutting technique. Specifically, the present invention relates to a method for determining the contents of 36 kinds of ODS in the atmosphere by using two capillary chromatographic columns with different polarities combined with a center-cutting technique. Background Art

[0002] Ozone depleting substances are a class of halogen compounds that can penetrate the troposphere and enter the stratosphere to destroy the ozone layer. There are many types of ODS, the most common of which are hydrofluorocarbons (HFCs), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), perfluorocarbons (PFCs), carbon tetrachloride (CTC), etc. Ozone layer depletion has become the world's second largest environmental problem. In order to better protect the ozone layer, we need to detect ODS in the atmosphere.

[0004] The monitoring of ODS in the atmosphere requires high measurement accuracy and a sensitive analysis system (the detection limit of the method must be below 1pmol / mol). At present, the ODS analysis method is mainly optimized based on the analysis method of VOCs (volatile organic compounds) in the atmosphere. However, the detection limit of ODS in the atmosphere is 2 to 3 orders of magnitude lower than that of VOCs. Therefore, the current mainstream VOCs analysis method in the atmosphere is far from meeting the precision control requirements of ODS, and the VOCs monitoring method cannot be simply applied to the monitoring and analysis of ODS.

[0005] Regarding the analysis and determination of ODS in the atmosphere, GCMS is currently mainly used in domestic and foreign literature, and the determination methods all use a single chromatographic column, and the type of chromatographic column used is mainly PLOT GasPro. The biggest disadvantage of the PLOT GasPro chromatographic column is that it is not water-resistant. After a few hundred milliliters of atmospheric samples are enriched by the pretreatment device, the moisture in the atmosphere cannot be 100% removed. As the number of sample measurements increases, the moisture will continue to accumulate in the PLOT GasPro chromatographic column, resulting in a decrease in the column efficiency of the PLOT GasPro chromatographic column. In severe cases, ODS peaks do not appear, which is very unfavorable for the quantitative analysis of ODS in the atmosphere.

[0006] Regarding the method detection limit and measurement accuracy of 36 ODS in the atmosphere, the data reported in domestic and foreign literatures show that the method detection limit of some ODS will be greater than 1pmol / mol and the measurement accuracy will be greater than 3%. For example, the method detection limit in the document "Canister Sampling-Preconcentration-Gas Chromatography-Mass Spectrometry Determination of 40 Ozone Depleting Substances in the Air" is 2.12-7.72pmol / mol, and the method detection limit in the document "Mobile-Gas Chromatography-Mass Spectrometry-Determination of 34 Ozone Depleting Substances in Ambient Air" is 0.18-0.93nmol / mol. Summary of the invention

[0008] In order to solve the above problems, the purpose of the present invention is to provide an analytical method that can accurately qualitatively and quantitatively analyze a variety of ODS. The detection limit of the present invention can reach below 1pmol / mol (the volume of the atmospheric sample is 800mL), and the measurement accuracy can reach within 3% at the pmol / mol concentration level, which solves the problem of low ODS concentration level in ambient air and difficulty in accurate monitoring.

[0009] The present invention adopts the following technical solutions:

[0010] The method of analyzing ozone-depleting substances in the atmosphere by dual-column combined with heart-cutting technology uses two capillary columns with different polarities combined with heart-cutting technology to separate ODS, and enters the mass spectrometer through the TwinLine system for qualitative and quantitative analysis.

[0011] SH-Rxi-624Sil MS was used as the first-dimensional chromatographic column, and PLOT GasPro was used as the second-dimensional chromatographic column.

[0012] The specific steps are:

[0013] (1) Dilute the ODS standard gas to obtain 100 pmol / mol and 2000 pmol / mol standard working gases respectively.

[0014] (2) After concentrating 100 pmol / mol of the standard working gas, it enters the GCMS and adopts the Scan mode for analysis. The central cutting is in the standby mode. All ODS enters the one-dimensional chromatographic column for separation and enters the MS detector for detection through the TwinLine system to find out the ODS that cannot be separated by the one-dimensional chromatographic column and determine the cutting time; during the cutting time period, the central cutting is in the cutting mode, and the ODS that cannot be separated by the one-dimensional chromatographic column enters the two-dimensional chromatographic column for separation and enters the MS detector for detection through the TwinLine system; the volume of the standard working gas in step (2) is 800 mL, which is pre-concentrated by Entech 7200 atmospheric concentrator.

[0015] (3) A SIM method was created based on the peak order of ODS on the first-dimensional chromatographic column and the second-dimensional chromatographic column.

[0016] (4) The standard gas was configured into an ODS standard series with different concentrations, and the analysis was performed in GCMS SIM mode. A low-concentration standard curve and a high-concentration standard curve were established with concentration as the horizontal axis and peak area as the vertical axis.

[0017] Specifically, the standard curve is prepared by the external standard method, and the concentration of the ODS standard gas in step (1) is 1 μmol / mol.

[0018] The process of establishing the low-concentration standard curve is as follows: Entech 7200 atmospheric concentrator extracts 20mL, 40mL, 80mL, 200mL, 400mL and 800mL of standard working gas with a concentration of 100pmol / mol, respectively, and prepares an ODS standard series with target concentrations of 2.5, 5, 10, 25, 50 and 100pmol / mol, respectively. The low-concentration standard curve is established with concentration as the horizontal axis and peak area as the vertical axis.

[0019] The process of establishing the high-concentration standard curve is as follows: Entech 7200 atmospheric concentrator extracts 20mL, 40mL, 80mL, 200mL, 400mL and 800mL of standard working gas with a concentration of 2000pmol / mol, respectively, and prepares an ODS standard series with target concentrations of 50, 100, 200, 500, 1000 and 2000pmol / mol, respectively. The high-concentration standard curve is established with concentration as the horizontal axis and peak area as the vertical axis.

[0020] The GCMS analysis conditions are as follows: injection port temperature 150°C to 220°C, split injection, split ratio: 10:1 to 20:1, column temperature program: 30°C to 40°C for 8 to 15 minutes, 4°C / min to 8°C / min to 50°C, 10°C / min to 15°C / min to 160°C, 8°C / min to 12°C / min to 220°C, and maintained for 3 to 6 minutes, carrier gas control mode: constant pressure, pressure program: 100kPa to 120kPa for 15 to 20 minutes, 2kPa / min to 6kPa / min to 140kPa to 160kPa, and maintained for 4 to 7 minutes, ionization mode: EI, ion source temperature: 200°C to 250°C, interface temperature: 200°C to 220°C. Detector voltage: +0.2 to 0.5kV relative to the tuning voltage, SIM mode to collect spectra.

[0021] (5) The atmospheric sample is pre-concentrated by a three-stage cold trap and then analyzed by GCMS, and an external standard curve is used to quantitatively analyze ODS. Preferably, the volume of the atmospheric sample is 800 mL.

[0022] The following table lists the quantitative ion and qualitative ion information of 36 ODS.

[0023]

[0024]

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention combines two chromatographic columns of different polarities, SH-Rxi-624Sil MS and PLOT GasPro. After pre-concentration and enrichment, the atmospheric sample first enters the one-dimensional chromatographic column SH-Rxi-624Sil MS for separation. After the concentrated sample passes through SH-Rxi-624Sil MS, the influence of moisture on the PLOT GasPro chromatographic column can be effectively eliminated, and 36 kinds of ODS can obtain good chromatographic peaks and separation.

[0027] 2. The contents of 36 ODS in atmospheric samples vary in high and low levels. The present invention prepares standard curves for low and high concentrations in sections, making quantification more accurate.

[0028] 3. By optimizing the analytical conditions, the present invention achieves that the detection limits of 36 ODS methods are all lower than 1 pmol / mol, and the measurement accuracy at the pmol / mol concentration level is less than 3%. DETAILED DESCRIPTION

[0029] Example 1

[0030] Main instruments and standard gas

[0031]

[0032] Three different analysis conditions were used to select the optimal Scan analysis method.

[0033] Condition 1: 100 pmol / mol ODS standard gas (800 mL) was concentrated by Entech 7200 atmospheric concentrator, and the concentrated standard gas entered GCMS and was analyzed in Scan mode, the injection port temperature was 180℃~220℃, the injection was split, the split ratio was 15:1~20:1, the column temperature program was: 35℃ for 8~15min, 4℃ / min~8℃ / min to 50℃, 10℃ / min~15℃ / min to 160℃, 8℃ / min~12℃ / min to 220℃, and kept for 3-6min, the carrier gas was controlled Mode: constant pressure, pressure program: 100 kPa, maintain for 8-16 min, 2 kPa / min-6 kPa / min to 140 kPa-160 kPa, maintain for 2-6 min, ionization mode: EI, ion source temperature: 200°C, interface temperature: 200°C; detector voltage: +0.2 kV relative to tuning voltage; m / z (45-280) acquisition spectrum, center cutting is in standby mode, all ODS enters the one-dimensional chromatographic column SH-Rxi-624Sil MS (60m x 0.32mm x 1.8um) for separation, and the cutting time is determined to be 7-12 min based on the peak elution of the SH-Rxi-624Sil MS chromatographic column. The program was set on the GCMSsolution workstation, and the heart cutting was in the cutting mode at 7 to 12 minutes. The ODS substances that could not be separated by the one-dimensional chromatographic column entered the two-dimensional chromatographic column PoraBond (50m x 0.32mm x 5um) for separation. The separated ODS substances entered the MS detection through the TwinLine system.

[0034] Condition 2: 100 pmol / mol ODS standard gas (800 mL) was concentrated by Entech 7200 atmospheric concentrator, and the concentrated standard gas entered GCMS and was analyzed in Scan mode, the injection port temperature was 150℃~200℃, the injection was split, the split ratio was 10:1~15:1, the column temperature program was: 35℃ for 8~15min, 4℃ / min~8℃ / min to 50℃, 10℃ / min~15℃ / min to 160℃, 8℃ / min~12℃ / min to 220℃, and kept for 3-6min, the carrier gas was controlled Mode: constant pressure, pressure program: 100kPa for 8-16min, 2kPa / min-6kPa / min to 140kPa-160kPa, maintain for 2-6min, ionization mode: EI, ion source temperature: 200℃, interface temperature: 220℃; relative to tuning voltage +0.2kV; m / z (45-280) acquisition spectrum, heart cutting is in standby mode, all ODS enters the one-dimensional chromatographic column SH-Rxi-624SilMS (60m x 0.32mm x 1.8um) for separation, and the cutting time is determined to be 7-12min according to the peak of the SH-Rxi-624Sil MS chromatographic column. Set the program on the GCMSsolution workstation, 7-12min heart cutting is in cutting mode, ODS substances that cannot be separated by the one-dimensional chromatographic column enter the two-dimensional chromatographic column CPVolamine (60m x 0.32mm) for separation, and the separated ODS substances enter the MS detection through the TwinLine system.

[0035] Condition 3: 100 pmol / mol ODS standard gas (800 mL) was concentrated by Entech 7200 atmospheric concentrator, and the concentrated standard gas entered GCMS and was analyzed in Scan mode, the injection port temperature was 150℃~200℃, the injection was split, the split ratio was 10:1~15:1, the column temperature program was: 35℃ for 8~15min, 4℃ / min~8℃ / min to 50℃, 10℃ / min~15℃ / min to 160℃, 8℃ / min~12℃ / min to 220℃, and kept for 1-6min, the carrier gas was controlled Mode: constant pressure, pressure program: 100kPa for 8-16min, 2kPa / min-6kPa / min to 140kPa-160kPa, maintain for 2-6min, ionization mode: EI, ion source temperature: 230℃, interface temperature: 220℃; relative to tuning voltage +0.2kV; m / z (45-280) acquisition spectrum, heart cutting is in standby mode, all ODS enters the one-dimensional chromatographic column SH-Rxi-624SilMS (60m x 0.32mm x1.8um) for separation, and the cutting time is determined to be 7-12min according to the peak of the SH-Rxi-624Sil MS chromatographic column. Set the program on the GCMSsolution workstation, 7-12min heart cutting is in cutting mode, ODS substances that cannot be separated by the one-dimensional chromatographic column enter the two-dimensional chromatographic column PLOT GasPro (60m×0.32mm x 5um) for separation, and the separated ODS substances enter the MS detection through the TwinLine system.

[0036] After the sample is concentrated by the atmospheric concentrator, it will contain trace amounts of water, so the water-resistant 6% cyanopropylphenyl 94% dimethylpolysiloxane SH-Rxi-624Sil MS is selected as the first-dimensional column. The use of PoraBond in the first and second-dimensional columns will lead to tailing of the ODS chromatographic peak, and the use of CPVolamine in the second-dimensional columns will have poor results in separating ODS. The use of PLOT GasPro in the third-dimensional columns will have better peak shape and separation than conditions one and two, so SH-Rxi-624Sil MS is selected as the first-dimensional column and PLOT GasPro is selected as the second-dimensional column for analysis.

[0037] Example 2

[0038] The method for analyzing ozone-depleting substances in the atmosphere using dual-column combined with heart-cutting technology has the following specific steps:

[0039] (1) Dilute 1 μmol / mol ODS standard gas using a diluter to obtain 100 pmol / mol and 2000 pmol / mol standard working gases respectively.

[0040] (2) Entech 7200 atmospheric concentrator was used to extract 20 mL, 40 mL, 80 mL, 200 mL, 400 mL and 800 mL of standard working gas with a concentration of 100 pmol / mol, respectively, to prepare a series of ODS standards with target concentrations of 2.5, 5, 10, 25, 50 and 100 pmol / mol, respectively. The concentrated standard working gas was fed into GCMS for analysis, and a low-concentration standard curve was established with concentration as the horizontal axis and peak area as the vertical axis.

[0041] (3) Entech 7200 atmospheric concentrator was used to extract 20 mL, 40 mL, 80 mL, 200 mL, 400 mL and 800 mL of standard working gas with a concentration of 2000 pmol / mol, respectively, to prepare an ODS standard series with target concentrations of 50, 100, 200, 500, 1000 and 2000 pmol / mol, respectively. The concentrated standard working gas was sent to GCMS for analysis, and a high concentration standard curve was established with concentration as the horizontal axis and peak area as the vertical axis.

[0042] (4) Determination of method detection limit: Referring to the determination of method detection limit in Appendix A of HJ 168-2020 Technical Guidelines for the Development of Environmental Monitoring Analytical Methods, 2.5 pmol / mol ODS standard gas was used for n=8 parallel determinations. The detection limits of 36 ODS methods were calculated to be 0.1-0.5 pmol / mol.

[0043] (5) Measurement accuracy: n=6 parallel measurements were performed using 5 pmol / mol ODS standard gas. The RSD% of the peak areas of 36 ODS species was calculated to be 0.9-2.3%.

[0044] (6) Sample determination: Atmospheric sample 1 (800 mL) was concentrated by Entech 7200 atmospheric concentrator and analyzed by GCMS. The contents of 36 ODS are shown in Table 1 below.

[0045] The GCMS analysis conditions are as follows: injection port temperature 200°C, split injection, split ratio: 10:1, column temperature program: 35°C for 15 min, 5°C / min to 50°C, 15°C / min to 160°C, 10°C / min to 220°C, hold for 1 min, carrier gas control mode: constant pressure, pressure program: 100 kPa for 15 min, 4 kPa / min to 155 kPa, hold for 3.5 min, ion source temperature: 200°C, interface temperature: 200°C, cutting time 8-11 min, detector voltage: +0.3 kV relative to the tuning voltage, and SIM mode to collect spectra.

[0046] Table 1 Contents of 36 ODS in atmospheric sample 1

[0047]

[0048] ND means not detected.

[0049] Example 3

[0050] The method for analyzing ozone-depleting substances in the atmosphere using dual-column combined with heart-cutting technology has the following specific steps:

[0051] (1) Dilute 1 μmol / mol ODS standard gas using a diluter to obtain 100 pmol / mol and 2000 pmol / mol standard working gases respectively.

[0052] (2) Entech 7200 atmospheric concentrator was used to extract 20 mL, 40 mL, 80 mL, 200 mL, 400 mL and 800 mL of standard working gas with a concentration of 100 pmol / mol, respectively, to prepare a series of ODS standards with target concentrations of 2.5, 5, 10, 25, 50 and 100 pmol / mol, respectively. The concentrated standard working gas was fed into GCMS for analysis, and a low-concentration standard curve was established with concentration as the horizontal axis and peak area as the vertical axis.

[0053] (3) Entech 7200 atmospheric concentrator was used to extract 20 mL, 40 mL, 80 mL, 200 mL, 400 mL and 800 mL of standard working gas with a concentration of 2000 pmol / mol, respectively, to prepare an ODS standard series with target concentrations of 50, 100, 200, 500, 1000 and 2000 pmol / mol, respectively. The concentrated standard working gas was sent to GCMS for analysis, and a high concentration standard curve was established with concentration as the horizontal axis and peak area as the vertical axis.

[0054] (4) Determination of method detection limit: Referring to the determination of method detection limit in Appendix A of HJ 168-2020 Technical Guidelines for the Development of Environmental Monitoring Analytical Methods, 2.5 pmol / mol ODS standard gas was used for n=8 parallel determinations. The detection limits of 36 ODS methods were calculated to be 0.1-0.8 pmol / mol.

[0055] (5) Measurement accuracy: n=6 parallel measurements were performed using 5 pmol / mol ODS standard gas. The RSD% of the peak areas of 36 ODS species was calculated to be 1.2-2.7%.

[0056] (6) Sample determination: Atmospheric sample 2 (800 mL) was concentrated by Entech 7200 atmospheric concentrator and analyzed by GCMS. The contents of 36 ODS are shown in Table 2 below.

[0057] The GCMS analysis conditions are as follows: injection port temperature 210°C, split injection, split ratio: 15:1, column temperature program: 35°C for 10 min, 5°C / min to 50°C, 15°C / min to 160°C, 10°C / min to 220°C, hold for 2 min, carrier gas control mode: constant pressure, pressure program: 100 kPa for 10 min, 4 kPa / min to 155 kPa, hold for 4.5 min, ion source temperature: 230°C, interface temperature: 200°C, cutting time 7-10.5 min, detector voltage: +0.35 kV relative to the tuning voltage, and SIM mode to collect spectra.

[0058] Table 2 Contents of 36 ODS in atmospheric sample 2

[0059]

[0060] ND means not detected.

[0061] Example 4

[0062] The method for analyzing ozone-depleting substances in the atmosphere using dual-column combined with heart-cutting technology has the following specific steps:

[0063] (1) Dilute 1 μmol / mol ODS standard gas using a diluter to obtain 100 pmol / mol and 2000 pmol / mol standard working gases respectively.

[0064] (2) Entech 7200 atmospheric concentrator was used to extract 20 mL, 40 mL, 80 mL, 200 mL, 400 mL and 800 mL of standard working gas with a concentration of 100 pmol / mol, respectively, to prepare a series of ODS standards with target concentrations of 2.5, 5, 10, 25, 50 and 100 pmol / mol, respectively. The concentrated standard working gas was fed into GCMS for analysis, and a low-concentration standard curve was established with concentration as the horizontal axis and peak area as the vertical axis.

[0065] (3) Entech 7200 atmospheric concentrator was used to extract 20 mL, 40 mL, 80 mL, 200 mL, 400 mL and 800 mL of standard working gas with a concentration of 2000 pmol / mol, respectively, to prepare an ODS standard series with target concentrations of 50, 100, 200, 500, 1000 and 2000 pmol / mol, respectively. The concentrated standard working gas was sent to GCMS for analysis, and a high concentration standard curve was established with concentration as the horizontal axis and peak area as the vertical axis.

[0066] (4) Determination of method detection limit: Referring to the determination of method detection limit in Appendix A of HJ 168-2020 Technical Guidelines for the Development of Environmental Monitoring and Analysis Methods, 2.5 pmol / mol ODS standard gas was used for n=8 parallel determinations. The detection limits of 36 ODS methods were calculated to be 0.1-0.9 pmol / mol.

[0067] (5) Measurement accuracy: n=6 parallel measurements were performed using 5 pmol / mol ODS standard gas. The RSD% of the peak areas of 36 ODS species was calculated to be 1.6-2.8%.

[0068] (6) Sample determination: Atmospheric sample 3 (800 mL) was concentrated by Entech 7200 atmospheric concentrator and analyzed by GCMS. The contents of 36 ODS are shown in Table 3 below.

[0069] The GCMS analysis conditions were as follows: injection port temperature of 220°C, split injection, split ratio: 10:1, column temperature program: 35°C for 15 min, 5°C / min to 50°C, 15°C / min to 160°C, 10°C / min to 220°C, and hold for 1 min, carrier gas control mode: constant pressure, pressure program: 100 kPa for 15 min, 5 kPa / min to 155 kPa, and hold for 6.3 min, ion source temperature: 200°C, interface temperature: 220°C, cutting time of 8-11 min, detector voltage: +0.3 kV relative to the tuning voltage, and spectra were collected in SIM mode.

[0070] Table 3 Contents of 36 ODS in atmospheric sample 3

[0071]

[0072]

[0073] ND means not detected.

Claims

1. A method for analyzing ozone-depleting substances in the atmosphere using a dual-column combined with a heart-cutting technique, characterized in that: Two capillary columns with different polarities were used in combination with the heart-cutting technique to separate ODS, which was then entered into the mass spectrometer through the TwinLine system for qualitative and quantitative analysis.

2. The method for analyzing ozone-depleting substances in the atmosphere using a dual-column combined with heart-cutting technology according to claim 1, characterized in that: SH-Rxi-624Sil MS was used as the first-dimensional chromatographic column, and PLOT GasPro was used as the second-dimensional chromatographic column.

3. The method for analyzing ozone-depleting substances in the atmosphere using a dual-column combined with heart-cutting technology according to claim 1, characterized in that: The specific steps are: (1) Dilute the ODS standard gas to obtain 100 pmol / mol and 2000 pmol / mol standard working gas respectively; (2) The 100 pmol / mol standard gas was concentrated and then entered into the GCMS for analysis in the Scan mode. The heart cutting was in the standby mode. All ODS entered the one-dimensional column for separation and entered the MS detector for detection through the TwinLine system. The ODS that could not be separated by the one-dimensional column was found and the cutting time was determined. During the cutting time period, the heart cut is in the cutting mode, and the ODS that cannot be separated by the one-dimensional chromatographic column enters the two-dimensional chromatographic column for separation and enters the MS detector for detection through the TwinLine system; (3) Create a SIM method based on the peak order of ODS on the first-dimensional chromatographic column and the second-dimensional chromatographic column; (4) The standard gas was configured into an ODS standard series with different concentrations, and the GCMS SIM mode was used for analysis. A low-concentration standard curve and a high-concentration standard curve were established with the concentration as the horizontal axis and the peak area as the vertical axis; (5) Atmospheric samples were pre-concentrated using a three-stage cold trap and then analyzed by GCMS, and ODS was quantitatively analyzed using an external standard curve.

4. The method for analyzing ozone depleting substances in the atmosphere using a dual-column combined with heart-cutting technology according to claim 1, characterized in that: The GCMS analysis conditions are as follows: injection port temperature 150°C to 220°C, split injection, split ratio: 10:1 to 20:1, column temperature program: 30°C to 40°C for 8 to 15 minutes, 4°C / min to 8°C / min to 50°C, 10°C / min to 15°C / min to 160°C, 8°C / min to 12°C / min to 220°C, and maintained for 3 to 6 minutes, carrier gas control mode: constant pressure, pressure program: 100kPa to 120kPa for 15 to 20 minutes, 2kPa / min to 6kPa / min to 140kPa to 160kPa, and maintained for 4 to 7 minutes, ionization mode: EI, ion source temperature: 200°C to 250°C, interface temperature: 200°C to 220°C. Detector voltage: +0.2 to 0.5kV relative to the tuning voltage, SIM mode to collect spectra.

5. The method for analyzing ozone-depleting substances in the atmosphere using a dual-column combined with heart-cutting technology according to claim 1, characterized in that: The concentration of the ODS standard gas in step (1) is 1 μmol / mol.

6. The method for analyzing ozone depleting substances in the atmosphere using a dual-column combined with heart-cutting technology according to claim 1, characterized in that: The volume of the standard gas used in step (2) is 800 mL, which is pre-concentrated using an Entech 7200 atmospheric concentrator.

7. The method for analyzing ozone depleting substances in the atmosphere using a dual-column combined with heart-cutting technology according to claim 1, characterized in that: The volume of the atmospheric sample in step (5) is 800 mL, and it is pre-concentrated using an Entech 7200 atmospheric concentrator.

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