Multi-component quantitative analysis method for polychloroprene in atmospheric particulates

Abstract

The invention discloses a multi-component quantitative analysis method for polychloroprene in atmospheric particulates, which comprises the following steps of: (1) collecting the atmospheric particulates in different particle size ranges by using a high-flow impact type grading particulate sampler and an aluminum foil or a quartz filter membrane; (2) respectively extracting the collected atmospheric particulates in different particle size ranges by using an extracting agent, concentrating the extracting agent, fixing the volume, and removing impurities; (3) analyzing polychlorobutadiene in the extract liquor after impurity removal by using a gas chromatography-triple quadrupole mass spectrometer; and (4) according to gas chromatography-triple quadrupole mass spectrometry data, performing qualitative and quantitative analysis on polychlorobutadiene in the atmospheric particulates with different particle size ranges. The analysis method disclosed by the invention can be used for simultaneously detecting various polychlorobutadiene in the atmospheric particulates, and has the advantages of simplicity in operation, high sensitivity, high selectivity and the like.

Description

Technical Field

[0001] The invention relates to the field of environmental detection, and in particular to a multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter. Background Art

[0002] Air pollution is one of the main factors that endanger the public health of my country. The environmental and health effects caused by air pollution are usually related to particulate matter pollution. Particles have a small particle size, stay in the air for a long time, have a large specific surface area, and are easy to adsorb or absorb compounds in the gas phase. These characteristics make the particles carry a large amount of organic or inorganic pollutants, which will cause significant health effects when they enter the human body through breathing. Generally speaking, the smaller the particle size of the particles, the easier it is to enter the deep airway, and the greater the harm to human health. For example, dust particles larger than 10μm are more likely to be intercepted by the trachea or middle bronchi, while particles of 5-10μm are more likely to be deposited in the tracheobronchial tree; when the particle size of the particles is smaller, it is more likely to pass through the tracheobronchial tree and enter the respiratory bronchioles and certain alveoli, thereby increasing the incidence of respiratory diseases, cardiovascular diseases and even cancer.

[0003] The health effects of particulate matter mainly come from the pollutants it carries. Fine particulate matter in the atmosphere is mainly composed of organic matter, water-soluble ions (SO 4 2- 、NO 3 - NH 4 + , K + , Ca 2+ 、Na + Mg 2+ Among them, organic matter is an important component of atmospheric fine particles, containing hundreds of organic compounds.

[0004] Persistent organic pollutants are characterized by persistence, bioaccumulation and high toxicity. Persistent organic pollutants in the atmosphere have always been an important focus of health risks related to particulate matter inhalation. Polychlorinated butadienes (polyCBDs) are olefin compounds containing multiple chlorine-substituted groups. They are a class of persistent organic pollutants with high toxicity, bioaccumulation and long-range migration, posing a serious threat to the ecological environment and human health.

[0005] Atmospheric particulate matter is an important carrier of polyCBDs, and the level of polychloroprene in particulate matter can reflect the regional pollution status and source characteristics. Therefore, it is necessary to establish an accurate, sensitive and efficient analytical method for polychloroprene in atmospheric particulate matter, which is of great significance for environmental monitoring and pollution control.

[0006] The existing methods are mainly for the analysis of hexachlorobutadiene in water, soil, organisms, dust and gas in environmental samples. There is currently no method for the analysis of polychlorobutadiene in atmospheric particulate matter.

[0007] The current methods have the problems of long time consumption, low sensitivity, poor selectivity, susceptibility to interference from other substances, and inability to meet the requirements of trace analysis. In addition, the traditional methods have many pre-treatment steps, complex operations, and long time consumption. For low-concentration samples, traditional methods are difficult to meet the detection requirements. Some methods are easily interfered by other compounds, affecting the accuracy of the analysis results. Summary of the invention

[0008] The invention provides a multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter, which can simultaneously detect multiple polychloroprene in atmospheric particulate matter and has the advantages of simple operation, high sensitivity, high selectivity and the like.

[0009] The technical solution of the present invention is as follows:

[0010] A multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter comprises the following steps:

[0011] (1) Use a high-flow impact-type graded particle sampler to collect atmospheric particles of different particle size ranges using aluminum foil or quartz filter membrane;

[0012] (2) using extractants to extract the collected atmospheric particulate matter of different particle size ranges, and then concentrating and fixing the extractants to remove impurities;

[0013] (3) The polychloroprene in the extract after impurity removal was analyzed by gas chromatography-triple quadrupole mass spectrometry; the mass spectrometry scanning mode was MRM mode, and a DB-5-MS chromatographic column was used for separation, and the column temperature was raised as follows: 30-60°C for 1-2 min; heated to 100-120°C at 10-30°C / min and held for 0-2 min; heated to 120-130°C at 0.5-2°C / min, and then heated to 140-150°C at 15-20°C / min and held for 0-3 min; heated to 290-300°C at 5-15°C / min and held for 0-2 min;

[0014] (4) Based on the gas chromatography-triple quadrupole mass spectrometry data, qualitative and quantitative analysis of polychloroprene compounds in atmospheric particulate matter of different particle size ranges was performed.

[0015] In step (1), the particle size ranges of atmospheric particulate matter in different particle size ranges are respectively >2.5 μm, 1.4-2.5 μm, 0.77-1.4 μm, 0.44-0.77 μm, 0.25-0.44 μm, and <0.25 μm.

[0016] Atmospheric particles with a diameter ≥ 0.25 μm are collected using aluminum foil, and atmospheric particles with a diameter < 0.25 μm are collected using a quartz filter membrane.

[0017] In step (1), a high-flow impact-type graded particulate sampler is used to collect atmospheric particulate matter, with a sampling flow rate of 50 to 150 L / min and a sampling time of 48 to 72 h.

[0018] The polychlorobutadiene is 1,1,2,3-tetrachlorobutadiene (1,1,2,3-TeCBD), (E)-1,1,3,4-tetrachlorobutadiene ((E)-1,1,3,4-TeCBD), 1,1,4,4-tetrachlorobutadiene (1,1,4,4-TeCBD), (Z)-1,1,3,4-tetrachlorobutadiene ((Z)-1,1,3,4-TeCBD), At least one of 1,1,2,4-tetrachlorobutadiene (1,1,2,4-TeCBD), 1,2,3,4-tetrachlorobutadiene (1,2,3,4-TeCBD), 1,1,2,4,4-pentachlorobutadiene (1,1,2,4,4-PeCBD), 1,1,2,3,4-pentachlorobutadiene (1,1,2,3,4-PeCBD), and hexachlorobutadiene (HCBD).

[0019] In step (2), the extractant is a mixed solvent of dichloromethane and n-hexane, and the volume ratio of dichloromethane to n-hexane is 1:0.5-2.

[0020] Most preferably, the extractant is a mixed solvent of dichloromethane and n-hexane, and the volume ratio of dichloromethane to n-hexane is 1: 1. When the extractant is used for extraction, the extraction efficiency of polychloroprene is good.

[0021] In step (2), extracting the atmospheric particulate matter collected by the aluminum foil comprises: cutting the aluminum foil collecting the atmospheric particulate matter into thin strips, adding an extractant, and ultrasonically extracting for 20 to 40 minutes.

[0022] For samples collected by quartz filter membrane, rapid solvent extraction (ASE) was used because the particles were tightly bound.

[0023] In step (2), extracting the atmospheric particulate matter collected by the quartz filter membrane includes: cutting the quartz filter membrane collecting the atmospheric particulate matter into pieces and placing them into an ASE extraction pool, adding an extractant, and statically extracting for 5 to 15 minutes at 80 to 120° C. and 10 to 12 MPa, and cycling 1 to 2 times.

[0024] Most preferably, in step (2), extracting the atmospheric particulate matter collected by the quartz filter membrane comprises: cutting the quartz filter membrane collecting the atmospheric particulate matter into pieces and placing them into an ASE extraction cell, adding an extractant, and performing static extraction at 100° C. and 10.34 MPa for 10 minutes, repeating the cycle once.

[0025] In step (2), the extract is filtered through a 0.45 μm nylon filter membrane to remove impurities.

[0026] Preferably, in step (3), the specification of the DB-5-MS chromatographic column is 60.0m×0.25mm×0.25μm, the ion source temperature is 250°C, the injection port temperature is 250°C, the transfer line temperature is 300°C, and the carrier gas is helium.

[0027] Further preferably, the temperature raising program of the chromatographic column is as follows: maintain at 50°C for 2 min; increase the temperature to 110°C at 20°C / min and maintain for 1 min; increase the temperature to 127°C at 1°C / min, and then increase the temperature to 145°C at 18°C / min and maintain for 3 minutes; increase the temperature to 300°C at 10°C / min and maintain for 2 min.

[0028] Furthermore, the qualitative and quantitative ions, collision energy, and retention time of polychloroprene are shown in the following table:

[0029]

[0030] In step (4), quantitatively analyzing each polychloroprene in atmospheric particulate matter of different particle size ranges includes: calculating the air mass concentration and particulate mass concentration of each polychloroprene in atmospheric particulate matter of different particle size ranges, respectively, and the calculation formula is as follows:

[0031]

[0032] In the formula, C Air is the air mass concentration, in pg / m 3 ; C p is the mass concentration of particulate matter, in ng / g; c is the concentration of polychloroprene, in μg / L; m is the mass of atmospheric particulate matter collected, in mg; V is the sampling flow rate, in L / min; t is the sampling time, in min.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The present invention simplifies the pretreatment steps, improves the extraction efficiency, and can meet the detection requirements for low-concentration samples;

[0035] (2) The present invention can reduce the interference of other compounds and improve the accuracy of the results;

[0036] (3) The present invention calculates the concentration of polychloroprene in atmospheric particulate matter of different particle size ranges, and can more accurately analyze the particle size distribution characteristics of polychloroprene. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is the chromatographic column heating program diagram of Comparative Example 1;

[0038] Figure 2 It is the chromatogram of the standard solution of Comparative Example 1;

[0039] Figure 3 This is a partial peak diagram of 1,2,4,5-tetrachlorobenzene and 1,2,3,5-tetrachlorobenzene in the standard solution chromatogram of Comparative Example 1;

[0040] Figure 4 This is the chromatographic column heating program diagram of Example 7;

[0041] Figure 5 is the chromatogram of the standard solution of Example 7;

[0042] Figure 6 This is a partial peak diagram of 1,2,4,5-tetrachlorobenzene and 1,2,3,5-tetrachlorobenzene in the standard solution chromatogram of Example 7;

[0043] Figure 7 The individual chromatograms of each target compound in the standard solution of Example 8;

[0044] Figure 8 This is the chromatogram of the target standard solution in SIM mode;

[0045] Fig. 9 This is the chromatogram of the target standard solution in MRM mode. DETAILED DESCRIPTION

[0046] The present invention will be further described in detail below in conjunction with the examples. It should be pointed out that the examples described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0047] The present invention explores and optimizes the pretreatment method of atmospheric particulate matter samples, mainly improving the extraction efficiency of the target object, extraction time, purification method, etc., with the aim of improving the extraction efficiency of the target object and accurately quantifying the pollutants in the sample as much as possible. The simulated sample is used in the optimization process of the pretreatment method. 50 μL of a polyCBDs mixed standard solution with a concentration of 1 mg / L is dripped on a blank aluminum foil, and it is naturally evaporated. The aluminum foil is cut into small pieces and placed in a glass centrifuge tube, and an organic solvent is added for ultrasonic extraction.

[0048] Examples 1-3

[0049] The extraction agent was optimized in sample pretreatment. The process is as follows:

[0050] In Examples 1-3, 10 mL of dichloromethane, 10 mL of a mixed solution of acetone: n-hexane = 1:1 (v / v), and 10 mL of a mixed solution of dichloromethane: n-hexane = 1:1 (v / v) were used to perform ultrasonic extraction on the same batch of simulated samples for 15 minutes, and the extraction liquid nitrogen was blown to 1 mL. The extraction efficiency was calculated by GC-QQQ sampling analysis.

[0051] One typical substance, hexachlorobutadiene (HCBD), was selected to evaluate the extraction efficiency. The calculated results of the extraction efficiency of HCBD in aluminum foil samples using different extractants were 62.64%, 35.12%, and 76.10%, respectively.

[0052] Taking into account the extraction effect and the safety of chemical reagents, a mixed solution of dichloromethane:n-hexane = 1:1 (v / v) was finally selected as the extraction agent to achieve the best extraction effect.

[0053] Embodiment 4-5

[0054] The ultrasonic extraction time was optimized as follows:

[0055] At 25°C, two groups of simulated samples were ultrasonically extracted with a mixed solution of 10 mL of dichloromethane: n-hexane = 1:1 (v / v). The ultrasonic extraction times of Examples 4 and 5 were 15 minutes and 30 minutes, respectively, and the extraction efficiency was calculated in the same way as above. The results are shown in Table 1. It was found that increasing the ultrasonic extraction time can further improve the extraction efficiency of the target. Therefore, the ultrasonic extraction time was selected as 30 minutes during the experiment. For the samples collected by the quartz filter, since the particles were tightly bound, rapid solvent extraction (ASE) was used for extraction.

[0056] Table 1 Extraction efficiency of target substances at different ultrasonic times

[0057]

[0058] Example 6

[0059] The extract needs to be purified to remove impurities before entering the instrument for analysis. Otherwise, the particles remaining in it may affect the instrument's test results or even reduce the instrument's service life. Most previous studies used SPE columns to purify the extract. The present invention uses Supelclean TM ENVI-Carb TMThe extract was purified using the SPE tube. The SPE column was first activated with 10 mL of dichloromethane and 10 mL of n-hexane, then the extract was added for adsorption, and finally the target was eluted with 10 mL of n-hexane. The results showed that although the SPE tube can effectively remove impurities in the extract, it will also adsorb 33% to 40% of the target substance, resulting in a low quality of the actual measured pollutants. The present invention also tried to use Jinteng 0.45 μm nylon filter membrane to filter the extract and found that it can also achieve a purification effect, and the loss of the target is about 10%.

[0060] Taking into account the ease of operation and the loss rate of the target product, a 0.45 μm nylon filter membrane was finally selected for extract purification.

[0061] The atmospheric particulate matter sample pretreatment process optimized by Examples 1-6 is as follows:

[0062] Cut the aluminum foil into strips, put them into a 15 mL glass centrifuge tube, add 8 mL of mixed solvent (dichloromethane: n-hexane = 1:1 (v / v)), and extract them by ultrasonic at 25 ° C for 30 minutes. The extract was concentrated to 1 mL under nitrogen blowing, filtered through a 0.45 μm nylon filter membrane, and then transferred to a gas chromatography injection vial for injection analysis.

[0063] The quartz filter samples were cut into pieces and then TM Dionex TM ASE TM 350 for accelerated solvent extraction, pressure of 1500 psi, temperature of 100°C, and the extractant was the same as the aluminum foil sample (dichloromethane:n-hexane = 1:1 (v / v)). The ASE program was: preheating for 5 minutes, standing for 5 minutes, 1 cycle, purging for 60 seconds, and the flushing volume was set to 50%. The extract was concentrated by rotary evaporation, concentrated to 1 ml by nitrogen blowing, filtered through a 0.45 μm nylon filter membrane, and transferred to a gas chromatograph injection vial for injection analysis.

[0064] Comparative Example 1

[0065] The concentration of polychloroprene in atmospheric particulate matter was analyzed by gas chromatography-triple quadrupole mass spectrometry (GC-QQQ), and the separation was performed using a DB-5-MS (60.0m×0.25mm×0.25μm) chromatographic column. The ion source temperature was 250℃, the injection port temperature was 250℃, the transfer line temperature was 300℃, and the carrier gas was helium. The heating program was as follows: 50℃ for 2min; heating to 130℃ at 20℃ / min and holding for 1min; heating to 250℃ at 5℃ / min and holding for 2min. The column heating program was as follows: Figure 1 shown.

[0066] It is roughly divided into two temperature rising gradients. The chromatogram of the 10 ppb standard solution obtained by this method (including 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, 1,3,5-trichlorobenzene, 1,2,3,4-tetrachlorobenzene, 1,2,3,5-tetrachlorobenzene, 1,2,4,5-tetrachlorobenzene, pentachlorobenzene, hexachlorobenzene, 1,1,3,4-tetrachlorobutadiene, 1,1,2,4-tetrachlorobutadiene, 1,1,2,3-tetrachlorobutadiene, 1,2,3,4-tetrachlorobutadiene, 1,1,4,4-tetrachlorobutadiene, 1,1,2,4,4-pentachlorobutadiene, 1,1,2,3,4-pentachlorobutadiene and hexachlorobutadiene, each 10 μg / L) is as follows Figure 2 As shown in the figure. The elution times of some substance peaks are close, and the peaks overlap and are difficult to separate. For example, the elution times of 1,2,4,5-tetrachlorobenzene and 1,2,3,5-tetrachlorobenzene are 17.25 minutes and 17.31 minutes respectively (as shown in the figure). Figure 3 There may be some overlap in peak areas, which may affect the accuracy of the quantitative results.

[0067] Example 7

[0068] The concentration of polychloroprene in atmospheric particulate matter was analyzed by gas chromatography-triple quadrupole mass spectrometry (GC-QQQ), and the separation was performed using a DB-5-MS (60.0m×0.25mm×0.25μm) chromatographic column. The ion source temperature was 250℃, the injection port temperature was 250℃, the transfer line temperature was 300℃, and the carrier gas was helium. The heating program was as follows: 50℃ for 2min; increase the temperature to 110℃ at 20℃ / min and maintain for 1min; increase the temperature to 127℃ at 1℃ / min, and then increase the temperature to 145℃ at 18℃ / min and maintain for 3 minutes; increase the temperature to 300℃ at 10℃ / min. The column heating program is as follows Figure 4 shown.

[0069] By reducing the heating rate and heating in multiple stages, the peak times of the target substances are staggered as much as possible. The chromatogram of the 10 ppb standard solution obtained by the new method is as follows: Figure 5 As shown in the chromatogram obtained by the new method, the peaks of different substances are more separated and the overlap between peaks is reduced. For example, the peaks of 1,2,4,5-tetrachlorobenzene and 1,2,3,5-tetrachlorobenzene do not overlap (as shown in Figure 2). Figure 6 The quantitative results are more accurate.

[0070] The final optimized heating program was as follows: hold at 50°C for 2 min; heat to 110°C at 20°C / min and hold for 1 min; heat to 127°C at 1°C / min, then heat to 145°C at 18°C / min and hold for 3 min; heat to 300°C at 10°C / min and hold for 2 min.

[0071] Example 8

[0072] The multi-component quantitative analysis method of polychloroprene in atmospheric particulate matter includes the following steps:

[0073] 1. Sample collection: A high-flow impact-type graded particle sampler was used to collect atmospheric particles of six different sizes with aluminum foil and quartz filter membranes (M1: >2.5μm, M2: 1.4-2.5μm, M3: 0.77-1.4μm, M4: 0.44-0.77μm, M5: 0.25-0.44μm, Bot filter: <0.25μm, atmospheric particles in the particle size range of M1 to M5 were collected with aluminum foil, and atmospheric particles <0.25μm were collected with quartz filter membranes), the sampling flow rate was 100L / min, and the sampling time was 48-72h.

[0074] 2. Sample preservation: Weigh the collected aluminum foil and quartz filter membrane, subtract the weight of the aluminum foil and quartz filter membrane before sampling, and get the mass of the collected atmospheric particulate matter. After weighing, wrap the aluminum foil and quartz filter membrane with new aluminum foil and store them in a -20℃ refrigerator for subsequent processing.

[0075] 3. Sample processing: Cut the aluminum foil into thin strips, put it into a 15mL glass centrifuge tube, add 10mL of dichloromethane:n-hexane = 1:1 (v / v) as the extractant, ultrasonically extract for 30min, transfer the extract to a new clean glass centrifuge tube, and blow nitrogen to 1mL. Cut the quartz filter into small pieces with clean scissors, put it into the ASE extraction cell, use dichloromethane:n-hexane = 1:1 (v / v) as the extractant, statically extract for 10min at 100℃ and 10.34MPa, and cycle once. The extract was rotary evaporated to 5-10mL, and blown nitrogen to 1mL. The extracts were all filtered through a 0.45μm nylon filter membrane to remove impurities before sampling and analysis.

[0076] 4. Sample analysis: The concentration of polychloroprene in atmospheric particulate matter was analyzed by gas chromatography-triple quadrupole mass spectrometer (GC-QQQ). The mass spectrometer scanning mode was MRM mode, and the DB-5-MS (60.0m×0.25mm×0.25μm) chromatographic column was used for separation. The ion source temperature was 250℃, the injection port temperature was 250℃, the transfer line temperature was 300℃, and the carrier gas was helium. The heating program was as follows: 50℃ for 2min; heating to 110℃ at 20℃ / min, and holding for 1min; heating to 127℃ at 1℃ / min, and then heating to 145℃ at 18℃ / min, and holding for 3 minutes; heating to 300℃ at 10℃ / min, and holding for 2min.

[0077] 5. The qualitative and quantitative ions, collision energies, and retention times of tetrachlorobutadiene (TeCBDs), pentachlorobutadiene (PeCBDs), and hexachlorobutadiene (HCBD) are shown in Table 2 below:

[0078] Table 2 Qualitative and quantitative ions, collision energy and retention time of polychloroprene

[0079]

[0080] The concentration of polychloroprene is c (μg / L), the mass of the collected particulate matter is m (mg), the sampling flow rate V = 100L / min, and the sampling time is t (min). The specific concentration of polychloroprene in atmospheric particulate matter is calculated to evaluate the pollution situation and trace the source of the pollutants. Target air mass concentration C Air (pg / m 3 ) and particle mass concentration C p (ng / g) is calculated as follows:

[0081]

[0082] The concentration of polychloroprene is c (μg / L) and the calculation method of the concentration is as follows:

[0083] The standard curve is a mixed standard solution of polyCBDs, and the concentration gradient of the standard curve is: 0.1μg / mL, 0.5μg / mL, 1μg / mL, 5μg / mL, 10μg / mL. The relationship between the target concentration and the peak area of ​​the chromatographic peak is calculated, and the standard curve is used to quantitatively analyze the polyCBDs concentration in the actual sample. The individual chromatograms of each target in the 10μg / mL standard solution are shown in Figure 2. Figure 7 shown.

[0084] Since mono-, di- and trichlorobutadiene cannot exist stably in the atmosphere, they are almost impossible to detect and have no corresponding isotope internal standard, so they are not considered in actual measurements.

[0085] Example 9

[0086] Sampling points are set up in a typical urban area, and the regional pollution situation is analyzed and the source of pollutants is analyzed through the measurement and evaluation of the project of the present invention. The specific process includes:

[0087] 1. Sampling point setting: A high-flow impact-type graded particulate sampler is placed at the sampling point. The brands and models of the samplers used in this embodiment are TSI and MOUDI. Six types of atmospheric particulate matter with different particle sizes are collected through the cutting heads of the sampler with different apertures. A rough aluminum foil filter membrane is used to cover the impact disk to collect the atmospheric particulate matter that impacts the impact disk. In this example, atmospheric particulate matter in the particle size range of M1 to M5 is collected with aluminum foil, and atmospheric particulate matter <0.25μm is collected with a quartz filter membrane. Samples are collected in a cycle of 48 hours.

[0088] 2. Sample processing and analysis: The particulate matter samples collected from September 6, 2023 to September 8, 2023 were processed and sampled for analysis (the pretreatment and sample analysis methods were the same as in Example 8). The concentration results of polychlorobutadiene in the atmospheric particulate matter are shown in Tables 3 and 4. The results show that the concentration of hexachlorobutadiene is relatively high, and it is the main pollutant.

[0089] Table 3 Distribution of air mass concentration of polychloroprene in atmospheric particulate matter from September 6, 2023 to September 8, 2023

[0090]

[0091] Table 4 Distribution of mass concentration of polychloroprene particles in atmospheric particulate matter from September 6, 2023 to September 8, 2023

[0092]

[0093] The advantages of the present invention are as follows:

[0094] 1. The present invention simplifies the pre-treatment steps, improves the extraction efficiency, and can meet the detection requirements for low-concentration samples.

[0095] 2. The present invention can reduce the interference of other compounds and improve the accuracy of the results.

[0096] In the same complex matrix, the signal-to-noise ratio (S / N) of the MRM mode of GC-QQQ is significantly improved, and the number of interfering peaks is reduced compared with the SIM mode of GC-MS. Figure 8 This is the chromatogram of the target standard solution in SIM mode. There are many impurity peaks and the baseline drifts. The signal-to-noise ratio is low, only 9.4, and there are many interfering peaks. Fig. 9This is the chromatogram of the target standard solution in MRM mode. The baseline is stable, there are fewer interfering peaks, and the highest signal-to-noise ratio is 4654.9, which is a significant improvement. Therefore, compared with the traditional SIM mode, the MRM mode can improve the accuracy of the experimental results.

[0097] 3. The present invention calculates the concentration of polychloroprene in atmospheric particulate matter of different particle size ranges, and can more accurately analyze the particle size distribution characteristics of polychloroprene.

[0098] 4. The present invention can evaluate the influence of meteorological factors in different time periods on the concentration of polychloroprene.

[0099] 5. In a specific implementation, the present invention can simulate the backward air mass trajectory for different sampling time periods based on the actual concentration analysis and evaluation results, and trace the source of pollutants within the time period.

[0100] 6. The present invention can evaluate the interaction between substances emitted by different pollution sources in the case of multiple pollution sources and emission types.

[0101] 7. In a specific implementation, for scenarios with multiple pollution sources, the present invention can adjust the sampling period to analyze and evaluate the average concentration of polychloroprene in different time periods, thereby reducing the impact of changes in environmental factors on pollutant concentrations.

[0102] The embodiments described above provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter, characterized in that: The following steps are involved: (1) Use a high-flow impact-type graded particle sampler to collect atmospheric particles of different particle size ranges using aluminum foil or quartz filter membrane; (2) using extractants to extract the collected atmospheric particulate matter of different particle size ranges, and then concentrating and fixing the extractants to remove impurities; (3) The polychloroprene in the extract after impurity removal was analyzed by gas chromatography-triple quadrupole mass spectrometry; the mass spectrometry scanning mode was MRM mode, and a DB-5-MS chromatographic column was used for separation, and the column temperature was raised as follows: 30-60°C for 1-2 min; heated to 100-120°C at 10-30°C / min and held for 0-2 min; heated to 120-130°C at 0.5-2°C / min, and then heated to 140-150°C at 15-20°C / min and held for 0-3 min; heated to 290-300°C at 5-15°C / min and held for 0-2 min; (4) Based on the gas chromatography-triple quadrupole mass spectrometry data, qualitative and quantitative analysis of polychloroprene compounds in atmospheric particulate matter of different particle size ranges was performed.

2. The multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter according to claim 1, characterized in that: The particle size ranges of atmospheric particulate matter in different particle size ranges are respectively >2.5μm, 1.4~2.5μm, 0.77~1.4μm, 0.44~0.77μm, 0.25~0.44μm, and <0.25μm.

3. The multi-component quantitative analysis method of polychloroprene in atmospheric particulate matter according to claim 1, characterized in that: Atmospheric particles with a diameter ≥ 0.25 μm are collected using aluminum foil, and atmospheric particles with a diameter < 0.25 μm are collected using a quartz filter membrane.

4. The multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter according to claim 1, characterized in that: The polychlorobutadiene is at least one of 1,1,2,3-tetrachlorobutadiene, (E)-1,1,3,4-tetrachlorobutadiene, 1,1,4,4-tetrachlorobutadiene, (Z)-1,1,3,4-tetrachlorobutadiene, 1,1,2,4-tetrachlorobutadiene, 1,2,3,4-tetrachlorobutadiene, 1,1,2,4,4-pentachlorobutadiene, 1,1,2,3,4-pentachlorobutadiene and hexachlorobutadiene.

5. The multi-component quantitative analysis method of polychloroprene in atmospheric particulate matter according to claim 1, characterized in that: The extractant is a mixed solvent of dichloromethane and n-hexane, and the volume ratio of dichloromethane to n-hexane is 1:0.5-2.

6. The multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter according to claim 3, characterized in that: Extracting atmospheric particulate matter collected by aluminum foil includes: cutting the aluminum foil collecting the atmospheric particulate matter into thin strips, adding an extractant, and ultrasonically extracting for 20 to 40 minutes; Extracting atmospheric particulate matter collected by the quartz filter membrane includes: cutting the quartz filter membrane collecting the atmospheric particulate matter into pieces and placing them into an ASE extraction pool, adding an extractant, and statically extracting for 5 to 15 minutes at 80 to 120° C. and 10 to 12 MPa, and circulating 1 to 2 times.

7. The multi-component quantitative analysis method for polychloroprene in atmospheric particulate matter according to claim 1, characterized in that: In step (3), the specification of the DB-5-MS chromatographic column is 60.0m×0.25mm×0.25μm, the ion source temperature is 250°C, the injection port temperature is 250°C, the transfer line temperature is 300°C, and the carrier gas is helium.

8. The multi-component quantitative analysis method of polychloroprene in atmospheric particulate matter according to claim 7, characterized in that: The temperature program of the chromatographic column is as follows: hold at 50°C for 2 min; increase the temperature to 110°C at 20°C / min and hold for 1 min; increase the temperature to 127°C at 1°C / min, then increase the temperature to 145°C at 18°C / min and hold for 3 min; increase the temperature to 300°C at 10°C / min and hold for 2 min.

9. The multi-component quantitative analysis method of polychloroprene in atmospheric particulate matter according to claim 8, characterized in that: The qualitative and quantitative ions, collision energy and retention time of polychloroprene are shown in the following table:

10. In step (4), quantitative analysis of polychloroprene in atmospheric particulate matter of different particle size ranges comprises: The air mass concentration and particulate mass concentration of each polychloroprene in atmospheric particulate matter of different particle size ranges were calculated respectively, and the calculation formula is as follows: In the formula, C Air is the air mass concentration, in pg / m 3 ; C p is the mass concentration of particulate matter, in ng / g; c is the concentration of polychloroprene, in μg / L; m is the mass of atmospheric particulate matter collected, in mg; V is the sampling flow rate, the unit is L / min; t is the sampling time, the unit is min.

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