Method for detecting and analyzing aromatic components in smoke

Abstract

The invention discloses a method for detecting and analyzing aromatic components in smoke. The method comprises the following steps: preparing smoke traps of a standard sample and a tobacco product; diluting the smoke traps by using an organic solvent at different concentration gradients to obtain a to-be-detected sample, and obtaining the fluorescence intensity of the aromatic components in the standard sample and the to-be-detected sample through ultraviolet fluorescence spectrometry; according to the fluorescence intensity and the dilution multiple of the to-be-detected sample, the to-be-detected sample used for contrastive analysis with the standard sample is screened, the concentration of the aromatic components in the smoke is calculated in combination with the dilution multiple, and the calculation formula is N = (Sm-S0) / (Sa-S0) * (Xm * a). According to the method, the total content of the aromatic components in the flue gas is accurately detected by utilizing the ultraviolet fluorescence spectrometry, the interference of other components in the flue gas is avoided, the detection time is shortened, the detection process is rapid and convenient, semi-quantitative or quantitative analysis is realized, and the method has obvious advantages compared with the traditional chromatography.

Description

Technical Field

[0001] This patent belongs to the field of flue gas aromatic component detection technology, specifically relating to a method for detecting and analyzing aromatic components in flue gas. Background Technology

[0002] Aromatic components are a significant source of aroma in tobacco products. They are a class of hydrocarbons and their derivatives with cyclic conjugated structures, ranging from simple benzene rings to complex polycyclic structures, exhibiting significant differences in chemical stability and biological activity. Most aromatic components are not native tobacco metabolites but are generated through the thermal decomposition, oxidation, or cyclization reactions of precursors such as sugars, amino acids, and carotenoids. Aromatic components directly stimulate olfactory receptors in the nasal cavity, thus contributing to the unique aroma characteristics of tobacco products. Their aroma quality significantly impacts the style and quality of tobacco products; therefore, the detection and monitoring of aromatic component content in tobacco products is a crucial step in controlling their quality.

[0003] Common methods for detecting aromatic components in flue gas include thin-layer chromatography (TLC), gas chromatography (GC), high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), liquid chromatography-tandem mass spectrometry (HPLC-MS / MS), and spectrometry. When using chromatographic methods, the composition of aromatic components in flue gas is extremely complex. The structures of high-molecular-weight aromatic components are not clearly defined, and their concentrations are extremely low, making effective detection impossible. Furthermore, standard samples are often unavailable for data analysis and comparison, making it difficult to obtain accurate and effective data on aromatic components. Ultraviolet differential spectroscopy (UVD spectroscopy), proposed by Professor Platt and others at the University of Heidelberg in the 1970s, utilizes the characteristic absorption structures of gas molecules at different wavelengths during light transmission in the atmosphere to achieve qualitative and quantitative measurements of gases. Based on the characteristic absorption structures of various gases at different wavelengths, qualitative judgments are made about the gases, and quantitative analysis is performed based on the magnitude of the absorption intensity. However, flue gas contains not only aromatic components but also a large number of non-aromatic components that absorb ultraviolet light, making accurate detection of aromatic components impossible.

[0004] When using spectroscopic methods for detection, clarifying the correspondence between the spectral signal and the target analyte, while avoiding interference from the solution and other components in the flue gas, is a prerequisite for extracting information about aromatic components from the spectrum. Obtaining a linear correspondence between spectral intensity and aromatic component content is also a necessary condition for obtaining valid results. Therefore, developing accurate spectroscopic detection methods for aromatic components in flue gas is crucial for detecting the total content of aromatic components in flue gas. Solving the aforementioned challenges in spectroscopic detection is a key difficulty in accurately detecting the content of aromatic components in flue gas. Summary of the Invention

[0005] The purpose of this patent is to provide a method for detecting and analyzing aromatic components in flue gas, so as to achieve accurate detection of the total content of aromatic components in flue gas using spectroscopy, avoid interference from other components in flue gas, and shorten the detection time.

[0006] To solve the above-mentioned technical problems, this patent adopts the following technical solution:

[0007] A method for detecting and analyzing aromatic components in flue gas, comprising the following steps:

[0008] Step A: Prepare standard samples;

[0009] Step B: Prepare smoke traps for tobacco products;

[0010] Step C: Dilute the flue gas collector with organic solvents at different concentration gradients to obtain the test sample, and obtain the fluorescence intensity of the aromatic components in the standard sample and the test sample by ultraviolet fluorescence spectroscopy.

[0011] Step D: Identify the sample concentration range where the sample concentration is linearly correlated with the fluorescence intensity; select sample data from the linear concentration range and calculate the concentration of aromatic components in the flue gas based on the dilution factor. The formula for calculating the concentration of aromatic components in the flue gas is as follows:

[0012]

[0013] Where N is the concentration of aromatic components in the flue gas, in ppm; S m S represents the fluorescence intensity of the sample at the same wavelength within a linear concentration range; a S0 represents the fluorescence intensity of the standard solution at the same wavelength; S0 represents the fluorescence intensity of the organic solvent at the same wavelength; X0 represents the fluorescence intensity of the standard solution at the same wavelength; m denoted as , where is the dilution factor of the sample to be tested relative to the flue gas trap; 'a' is the ratio of the mass of the prepared flue gas trap to the mass of flue gas trapped on the Cambridge filter.

[0014] Furthermore, in step A, the concentration of the standard sample is 4–10 ppm.

[0015] Furthermore, step B includes:

[0016] Step B-1: Balance tobacco products, and smoke the balanced tobacco products.

[0017] Step B-2: Collect the smoked tobacco products and process the mainstream smoke or aerosol to obtain smoke traps.

[0018] Furthermore, B-1 specifically involves: balancing tobacco products for 72 hours, then using a smoking machine to inhale the balanced tobacco products in a standard smoking mode to obtain the mainstream smoke or aerosol of the tobacco products.

[0019] Specifically, B-2 involves: collecting mainstream flue gas or aerosols using a Cambridge filter, weighing the mass before and after collection using the Cambridge filter, and calculating the mass of the mainstream flue gas or aerosols; diluting the mainstream flue gas or aerosols at least 50 times with an organic solvent, centrifuging at low temperature, and then extracting the flue gas trap.

[0020] Furthermore, the equilibrium temperature for tobacco products is 21–23°C, and the equilibrium humidity is 57–63%.

[0021] The organic solvent is anhydrous methanol, a mixture of anhydrous methanol and chloroform, or a mixture of anhydrous methanol and dichloromethane.

[0022] Furthermore, in step C, ultraviolet fluorescence spectroscopy is performed using an ultraviolet fluorescence spectrometer.

[0023] Furthermore, the constant energy difference between the excitation light and fluorescence during fluorescence spectroscopy scanning was 1400 cm⁻¹. -1 Or 2800cm -1 The excitation wavelength scanning range is 200–700 nm; the excitation spectrum scanning speed is 100–300 nm / min; the slit widths of the emission and receiving optical paths are the same, at 2.5 nm or 5 nm; and the sensitivity of the detection instrument is 25–75% of the upper limit of the maximum peak intensity of the detection data.

[0024] Furthermore, in step D, the method for screening sample data within the linear concentration range is as follows: Ultraviolet fluorescence spectroscopy is performed on each concentration solution sample and the organic solvent to obtain the fluorescence spectrum dataset S of the sample to be tested. m And organic solvent spectrum dataset S0.

[0025] Furthermore, the peak intensity values ​​of different fluorescence spectra at the same wavelength were compared, and the numerical values ​​(S) were calculated. m+1 -S0 / S m -S0) and (S m -S0 / S m-1 -S0), the filtering results match (S m+1 -S0 / S m -S0)=(m / m+1) and (S m -S0 / S m-1 The data is -S0)<(m-1 / m).

[0026] Furthermore, when the excitation wavelength is in the range of 250–290 nm, it is a monocyclic aromatic compound;

[0027] When the excitation wavelength is in the range of 290–320 nm, it is an aromatic compound with two rings;

[0028] When the excitation wavelength is in the range of 320–500 nm, it is a fused-ring aromatic compound with three or more rings.

[0029] This patent provides a method for detecting and analyzing aromatic components in flue gas, avoiding interference from other non-aromatic components and directly and more accurately obtaining the signals and concentrations of aromatic substances in complex flue gas compositions. This invention avoids the problem of disproportionate sample concentration and fluorescence signal intensity due to the self-absorption of fluorescence by aromatic components caused by unsuitable sample concentrations. Therefore, this method can establish a direct proportional functional relationship between the content of aromatic components in flue gas and the fluorescence signal intensity, enabling quantitative / semi-quantitative analysis. Furthermore, the ultraviolet fluorescence detection signal is highly sensitive and can accurately measure signals at the ppm level, offering significant advantages over traditional chromatography for detecting low-concentration aromatic components in the flue gas of low-tar cigarette products. Attached Figure Description

[0030] The above content of this patent and the following detailed embodiments will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are merely examples of the claimed technical solution.

[0031] Figure 1 The image shows the UV fluorescence spectrum detection results of the blank solvent in this patent embodiment (where the horizontal axis is wavelength in nm and the vertical axis is fluorescence intensity in au).

[0032] Figure 2 The graph shows the detection results of the ultraviolet fluorescence spectrum of the flue gas solvent diluted 100 times in this patent after subtracting the blank (where the horizontal axis is wavelength in nm and the vertical axis is fluorescence intensity in au).

[0033] Figure 3 The graph shows the detection results of the ultraviolet fluorescence spectrum of the flue gas solvent diluted 400 times in this patent after subtracting the blank (where the horizontal axis is wavelength in nm and the vertical axis is fluorescence intensity in au).

[0034] Figure 4 The graph shows the ultraviolet fluorescence spectrum detection results of the standard solution in this patent (where the horizontal axis is wavelength in nm and the vertical axis is fluorescence intensity in au).

[0035] Figure 5 The graph shows the chromatographic detection results in the comparative example of this patent (where the horizontal axis represents the residence time in minutes, and the vertical axis represents the signal intensity). Detailed Implementation

[0036] The detailed features and advantages of this patent are described below in the specific embodiments. The content is sufficient to enable any person skilled in the art to understand the technical content of this patent and implement it accordingly. Based on the specification, claims and drawings disclosed in this specification, a person skilled in the art can easily understand the related objectives and advantages of this patent.

[0037] In this specification and claims, several terms will be used, and unless otherwise indicated, these terms will be defined to have the following meanings:

[0038] The terms “comprising” or “having” have the same meaning as “containing”, and also include other forms of the term, such as the gerund and singular forms in English, meaning including but not limited to, and not intended to exclude, for example, other elements, components, integers or steps.

[0039] "At least two" means two or more;

[0040] "At least 3" means 3 or more;

[0041] All other terms used herein for special definition are intended to have the general meaning understood by one of ordinary skill in the art, in particular meaning that one of ordinary skill in the art, upon reading the claims, specification and drawings of this patent, can directly and without doubt determine how the technical solution of this patent can be implemented.

[0042] All figures used to represent component amounts, properties (e.g., weight-average molecular weight), reaction conditions, etc., should be considered to be modified in all cases by the terms "within the unavoidable margin of error" or "approximately". Therefore, the numerical values ​​presented herein are approximate and may vary depending on the desired properties sought to be obtained by this patent. The principle of equivalents, which is applied to a minimum and not intended to limit the scope of the claims, should be applied, for example, each value should be interpreted at least according to the reported significant digits and by applying conventional rounding techniques.

[0043] All other terms used herein for special definition are intended to have the general meaning understood by one of ordinary skill in the art, in particular meaning that one of ordinary skill in the art, upon reading the claims, specification and drawings of this patent, can directly and without doubt determine how the technical solution of this patent can be implemented.

[0044] Even if there are incomplete descriptions, omissions, or ambiguities in the grammar, words, punctuation, graphics, symbols, etc. of the claims, specification, and drawings of this patent, a person skilled in the art can still arrive at the only correct understanding by reading the claims, specification, and drawings as a whole without extensive reasoning or experimentation, and effectively exclude various incorrect interpretations that are not aimed at achieving the purpose of this patent.

[0045] Those skilled in the art would first choose to read the claims, specification, and drawings of this patent to reasonably interpret the terms; secondly, they would choose to refer to the relevant definitions in other documents published by the applicant before the filing date to reasonably interpret the terms; thirdly, they would choose the references cited in this patent to reasonably interpret the terms; and finally, they would choose to combine the technical dictionaries, technical manuals, reference books, textbooks, national or industry technical standards, etc., commonly used by those skilled in the art to reasonably interpret the terms.

[0046] All references cited in this application are incorporated herein by way of citation in their entirety, to the extent that they do not contradict the disclosure herein. It will be apparent to those skilled in the art that products (apparatus, components, devices, compounds, compositions, materials, etc.) and methods (processes, steps, conditions, parameters, equipment, and test methods, equipment, etc.) not specifically described herein can be applied to the implementation of the invention fully disclosed herein without the need for excessive experimentation. This patent is intended to cover all functional equivalents known in the art of the methods, apparatus, apparatus components, materials, processes, and techniques specifically described herein.

[0047] Furthermore, multiple publications are referenced throughout this specification. To provide a more comprehensive description of the current state of the art in which this disclosure pertains, the entire contents of these publications are incorporated herein by reference. With regard to the content contained in published documents and in the statements that cite them, each published document is also incorporated herein by reference individually and specifically.

[0048] All the components used in this patent can be prepared by various known methods that are fully disclosed in the chemical literature.

[0049] Before disclosing and describing the materials, compounds, compositions, articles, apparatus, and methods of this patent, it should be understood that the following aspects are not limited to specific synthetic methods or specific reagents, as these are of course subject to variation. It should also be understood that the terminology used herein is for descriptive purposes only and not for limitation.

[0050] (1) Source of sample materials

[0051] The tobacco product in this patent is commercially available, specifically heated cigarette COO 01.

[0052] (2) Source of reagents and consumables

[0053] Table 1. Sources and Product Codes of Reagents and Consumables Required for the Experiment

[0054] name Manufacturers Item number Cambridge Filters Whatman, UK F319-04 Anhydrous methanol (HPLC grade) Sinopharm Reagent 80080418 Dichloromethane (HPLC grade) Sinopharm Reagent 40071190 0.45μm filter membrane MF-Millipore HAWPO4700

[0055] (3) Source of instruments and equipment

[0056] Table 2. Sources and Models of Instruments and Equipment Required for the Experiment

[0057]

[0058] Example

[0059] This patent provides a method for detecting and analyzing aromatic components in flue gas, the method comprising the following steps:

[0060] S1. Preparation of standard samples

[0061] Standard sample preparation: The smoke components of the heated cigarette standard product to be tested were simultaneously detected and analyzed using the standard methods of "WHO TobLabNet Official Method SOP09", "YQ / T 55-2015", and "YC / T 255-2008". Based on the categories and contents of aromatic components in the detected smoke components, standard chemicals were used to prepare standard samples of aromatic component mixtures according to the test results.

[0062] Weigh 40 mg of the aromatic component mixture standard sample using a high-precision balance (1 / 100,000 accuracy). Transfer the weighed sample to a glass bottle. Calculations show that the dilution factor required to dissolve and dilute to 4 ppm is 10,000 times. Perform two 100-fold dilutions of the aromatic component sample to achieve a concentration of 4 ppm. Place the glass bottle containing 40 mg of sample on the high-precision balance. Further use a pipette to transfer 3960 mg of organic solvent to the glass bottle to dissolve the sample. After thorough dissolution, take another 40 mg of the dissolved sample from the first dilution and transfer it to a new glass bottle. Place the glass bottle on the high-precision balance again and use a pipette to transfer the second 3960 mg of organic solvent required for the second dilution to the glass bottle to dissolve the sample. This yields a flue gas sample standard solution with a concentration of 4 ppm. During the dilution process, precisely control the mass of the transferred organic solvent according to the real-time balance readings to ensure accurate concentration. Seal the glass bottle to obtain a standard sample with a concentration (Na) of 4 ppm, ready for use.

[0063] In other specific embodiments, standard samples with a concentration of 4 to 10 ppm can also be prepared according to the above method.

[0064] S2. Preparation of smoke traps in tobacco products, the steps are as follows:

[0065] (1) Place ten cigarettes of COO 01 tobacco products purchased from the market in a room with constant temperature and humidity for 72 hours before smoking. The temperature for equilibration of the tobacco products is 21℃ and the humidity is 58%.

[0066] (2) After equilibration for 72 hours, it is used for subsequent smoking in a smoking machine. The smoking conditions meet the Canadian standard smoking mode recommended by the World Health Organization Tobacco Product Regulation Study Group, namely, a smoking volume of 35 mL, a smoking duration of 2 seconds, a smoking interval of 60 seconds, and smoking parameters that do not block the ventilation holes, generating COO 01 mainstream smoke in the smoking machine.

[0067] (3) The COO 01 mainstream smoke was collected by TPM (Total Particulate Matter) using a Cambridge filter with a diameter of 92 mm. The Cambridge filter is a glass fiber sheet fixed with an organic adhesive (polyacrylate), which can effectively retain the total particulate matter at room temperature. The weight of the mainstream smoke before and after collection by the Cambridge filter was measured, and the difference between the two was used to obtain the mass of 110 mg.

[0068] (4) The COO 01 mainstream flue gas on the Cambridge filter was extracted using anhydrous methanol as the organic solvent to obtain the original COO 01 flue gas solution sample.

[0069] The specific steps are as follows: The device containing a Cambridge filter rich in COO 01 mainstream smoke is placed in a high-speed centrifuge in situ. The smoke on the Cambridge filter is diluted 50 times with anhydrous methanol, i.e., the mass ratio of smoke to anhydrous methanol is 1:49. Then, high-speed centrifugation extraction is performed, and the centrifuged liquid is collected and filtered through a 0.45μm sterile filter membrane to obtain the original COO 01 smoke solution sample, which is the smoke trap in tobacco products. The concentration of smoke components in the original COO 01 smoke solution sample is 0.02ppm, i.e., the smoke component concentration is 0.02ppm.

[0070] (5) Further dilute the tobacco product smoke trap obtained in step (4) above multiple times stepwise to obtain test samples at each concentration gradient. Further dilute the tobacco product smoke trap with a smoke component concentration of 0.02 ppm by 10, 20, 50, 100, 200, and 400 times stepwise, and record the cumulative dilution factor (X) for each sample. m The components of the flue gas in the samples are denoted as X1, X2, X3, X4, X5, and X6, respectively, resulting in six samples to be tested. The concentrations of the flue gas components in the six samples are 2 × 10⁻⁶. -3 ppm, 1×10 -3 ppm, 4×10 -4 ppm, 2×10 -4 ppm, 1×10 -4 ppm and 5×10 -5 ppm.

[0071] In other specific embodiments, the equilibrium temperature of the tobacco product can also be 21–23°C, and the equilibrium humidity can be 58–63%. The organic solvent can be anhydrous methanol / chloroform mixed solution or anhydrous methanol / dichloromethane mixed solution. Alternatively, a 0.45 μm sterile filter membrane can be added after extraction to remove impurities, obtaining a tobacco product collectible free of impurities. Similarly, the dilution factor X... m It can also be modified according to actual needs.

[0072] S3, Ultraviolet Fluorescence Spectroscopy Analysis

[0073] Ultraviolet fluorescence spectroscopy analysis is based on ultraviolet fluorescence spectrometers, which are instruments used to measure the fluorescence emission spectra of substances. It is based on the principle that ultraviolet light excites substances to produce fluorescence, and analyzes and studies the properties and composition of samples by measuring the fluorescence spectrum.

[0074] The working principle of an ultraviolet fluorescence spectrometer is as follows:

[0075] a. Excitation source: Ultraviolet fluorescence spectrometers typically use xenon or deuterium lamps as excitation sources, emitting ultraviolet light. These light sources have high energy, which can excite electrons in the sample to transition to an excited state.

[0076] b. Optical System: The ultraviolet fluorescence spectrometer contains a complex optical system used to collect and analyze the fluorescence signals emitted by the sample. This system includes elements such as lenses, filters, and gratings, used to focus, disperse, and select light of specific wavelengths.

[0077] c. Sample cell: The sample cell is where the sample is placed, and it is usually made of quartz or glass. When the sample is exposed to ultraviolet light, it undergoes electron excitation and fluorescence emission.

[0078] d. Detector: Ultraviolet fluorescence spectrometers typically use photomultiplier tubes or photodiodes as detectors to convert fluorescent photons into electrical signals and amplify and measure the intensity of those signals.

[0079] e. Data processing: By converting the electrical signal output by the detector into a digital signal, and then amplifying and filtering it, the ultraviolet fluorescence spectrometer can generate fluorescence spectra. These spectra can be used to analyze the chemical composition, structure, and properties of samples.

[0080] (1) Ultraviolet fluorescence spectroscopy detection:

[0081] Using anhydrous methanol as the blank solvent, ultraviolet fluorescence spectroscopy was employed to analyze the concentrations of standard solutions, blank solvent, and randomly sampled flue gas components at 2 × 10⁻⁶ m³ / s. -4 The sample to be tested is marked as sample 1, and the concentration of flue gas components is 5 × 10⁻⁶. -5 The sample to be tested was marked as sample number 2 and tested.

[0082] The ultraviolet fluorescence spectroscopy detection conditions include: a constant energy difference between the excitation light and fluorescence during scanning is set to 2800 cm⁻¹. -1 The excitation spectrum scanning range is 250–500 nm; the excitation spectrum scanning speed is 200 nm / min; the slit width of the emission and receiving optical paths is the same, 2.5 nm; and the signal amplification intensity (sensitivity) of the detection instrument is set to 75% of the maximum peak intensity of the detection data.

[0083] In other specific methods, the constant energy difference between excitation light and fluorescence during ultraviolet fluorescence spectroscopy scanning can also be set to 1400 cm⁻¹. -1 Or 2800cm -1 The excitation spectral scanning range is 200–700 nm, where excitation wavelengths of 250–290 nm represent monocyclic aromatic compounds, 290–320 nm represent 2-ring aromatic compounds, and excitation wavelengths greater than 320–500 nm represent fused-ring aromatic compounds with three or more rings. The excitation spectral scanning speed is 100–300 nm / min. The slit widths of the emission and receiving optical paths are the same, at 2.5 nm or 5.0 nm. The signal amplification intensity (sensitivity) of the detection instrument is set to 25–75% of the maximum peak intensity of the detection data, which is the upper limit of the instrument's detection range.

[0084] The fluorescence spectrum results of the standard solution are as follows: Figure 1 As shown, the fluorescence intensity of the standard solution is labeled Sa. Combined with the fluorescence spectrum of the blank solvent, it can be seen that the fluorescence intensity signal of the standard solution is mainly concentrated between 250 and 400 nm, which is consistent with the composition of the aromatic components in heated cigarette smoke, which are mainly small-molecule 1-2 ring aromatic compounds and a small amount of fused-ring aromatic compounds with 3 or more rings.

[0085] The fluorescence spectrum results of the blank solvent are as follows: Figure 2 As shown, the fluorescence intensity of the blank solvent is marked as S0. The fluorescence signal in the figure is mainly the basic signal of the methanol solution under this test method. The signal of the test sample after subtracting this basic signal is the signal of the aromatic component.

[0086] The fluorescence intensity of the sample to be tested is labeled as S. m Among them, the fluorescence spectrum of sample No. 1 after subtracting the blank is as follows: Figure 3 As shown, the fluorescence intensity of sample 1 is labeled S1; the fluorescence spectrum of sample 2 after subtracting the blank is shown below. Figure 4 As shown, the fluorescence intensity of sample 1 is labeled S2. Comparative analysis. Figure 3 and Figure 4It was found that the difference in fluorescence signal intensity and sample concentration between the two samples was 4-fold, indicating that the samples entered the effective linear range after being diluted 100-fold, and the data can be used for further analysis.

[0087] (2) Data processing of ultraviolet fluorescence spectra

[0088] Based on the ultraviolet fluorescence spectral signals S0, S1, and S2 obtained in step (1) above, respectively, compare them with the ultraviolet fluorescence spectral signal S of the standard solution. a The concentration of aromatic components in the sample is calculated by comparing the results.

[0089] That is, take the fluorescence intensity data S of the sample to be tested respectively. m Fluorescence intensity data S of standard samples with a concentration of 4 ppm a After subtracting the fluorescence intensity data S0 of the blank organic solvent, the peak intensity values ​​at the same wavelength are used for calculation, as shown in the following formula:

[0090]

[0091] Where N is the concentration of aromatic components in the sample to be tested, and S m S represents the fluorescence intensity of the sample under any concentration gradient m at the same wavelength; a S0 is the fluorescence intensity of the standard solution at the same wavelength; S0 is the fluorescence intensity of the blank organic solvent at the same wavelength; X0 is the fluorescence intensity of the standard solution at the same wavelength; m denoted as , where is the dilution factor of the sample to be tested relative to the flue gas trap with a flue gas component concentration of 0.02 ppm; a is the dilution factor of the mass of flue gas trapped on the Cambridge filter during the preparation of the flue gas trap.

[0092] The results showed that at a wavelength of 280 nm, the fluorescence intensity peak S1 at a 100-fold dilution was 164.6, the fluorescence intensity peak S2 at a 400-fold dilution was 60.8, the fluorescence intensity peak S0 of the blank organic solvent was 25.5, and the fluorescence intensity peak S of the standard solution was... a It is 63.7.

[0093] The formula above can be used to calculate (S2-S0) / (S a -S0)=0.924. Therefore, compared with the No. 2 test sample diluted 400 times, the concentration of aromatic components in the No. 1 test sample diluted 400 times is 0.924×4=3.696ppm. Thus, the concentration of aromatic components in the flue gas solution sample is 3.696×100=369.6ppm. Therefore, the concentration of aromatic components in the flue gas on the Cambridge filter is 369.6×50=18480ppm, that is, the concentration of aromatic components in the flue gas is 1.848wt%.

[0094] Comparative Example

[0095] The difference between this comparative example and the previous one is that this comparative example uses gas chromatography-mass spectrometry to detect the concentration of aromatic components in tobacco product smoke traps. The specific steps are as follows:

[0096] (1) Take 10 mL of anhydrous methanol to dissolve the smoke collected on the Cambridge filter, filter it through a 0.45 μm sterile filter membrane to remove impurities, and obtain tobacco product collection without impurities.

[0097] (2) The above-mentioned tobacco product trap solution free of impurities was analyzed by GC-MS (gas chromatography-mass spectrometry). The capillary column used was a DB-Wax (30m length, 0.25mm inner diameter, 0.25μm thickness). The GC-MS injection volume was set to 1μL / sample, the carrier gas was high-purity helium (purity >99.99%), the flow rate was 1.0mL / min, and the injection was performed in splitless mode. The mass spectrometer source temperature was 230℃, and the quadrupole temperature was 150℃. The mass spectrometry scan range was 15–500 m / z. The mass spectrometry delay time was set to 4.7 min. The injection port temperature was set to 250℃, and the column temperature program was: hold at 40℃ for 3 min, then increase to 250℃ at a rate of 5℃ / min and hold for 10 min.

[0098] (3) The results obtained by GC-MS detection were compared with the database of the National Bureau of Standards and Technology (2014 edition).

[0099] The results are as follows Figure 5 As shown in the figure, nicotine (at 25.57 min) and other aromatic compounds were identified, mainly phenol (at 28.66 min), 3-methylphenol (at 30.13 min), lichenol (at 45.1 min), and hydroquinone (at 45.51 min).

[0100] It can be seen that gas chromatography-mass spectrometry has the following limitations, which make it impossible to further analyze the content of aromatic components in the sample: (1) it is difficult to detect larger aromatic compounds; (2) it has limited ability to resolve substances that show signals in the chromatogram, and can only resolve substances contained in the chromatogram library, while other uncommon aromatic components cannot be resolved due to the increasing number of standard samples.

[0101] Therefore, it can be concluded that the method for detecting and analyzing aromatic components in flue gas provided by this patent can avoid interference from other non-aromatic components in flue gas, directly obtain the aromatic component signals in complex flue gas components, and obtain more accurate aromatic component concentrations. It avoids the problem of disproportionate sample concentration and fluorescence signal intensity due to the self-absorption phenomenon of fluorescence components during the detection of aromatic components in flue gas caused by inappropriate concentrations. Therefore, the method of this invention can establish a direct proportional functional relationship between the content of aromatic components in flue gas and the fluorescence signal intensity, enabling quantitative / semi-quantitative analysis. Furthermore, the ultraviolet fluorescence detection signal is highly sensitive and can accurately measure signals at the ppm level, showing a significant advantage over traditional chromatography methods for detecting low-concentration aromatic components in the flue gas of low-tar cigarette products.

[0102] In this patent, references to "an embodiment" or "a specific implementation" mean that a particular feature, structure, or characteristic described in connection with that embodiment / specific implementation is included in at least one embodiment / specific implementation of this patent. Therefore, the phrase "in one embodiment / specific implementation" appearing in various places in this specification does not necessarily refer to the same embodiment / setting, but rather to a range of possibilities. Furthermore, specific features, structures, or characteristics may be combined in one or more embodiments / settings in any suitable manner, as will be apparent to those skilled in the art from this disclosure.

[0103] Similarly, it should be understood that in the above description of exemplary embodiments / specific implementations of this patent, various features of this patent are sometimes combined in a single embodiment / specific implementation or its figures and description, with the aim of simplifying the disclosure and aiding in the understanding of one or more of the various inventive aspects. However, except for expressly stated instructions to the contrary or obvious technical contradictions or exclusions, the descriptive method of this patent should not be construed as reflecting an intention that the claimed features of the invention are more than those expressly stated in each claim. Rather, the inventive aspects reflected in the claims lie in not all the features of a single foregoing disclosed embodiment / specific implementation. Therefore, the claims following the detailed description are expressly incorporated herein by reference, and each claim exists independently as a separate embodiment / specific implementation of this patent.

[0104] Furthermore, while some embodiments / specific implementations described herein include, but are not limited to, other features included in other embodiments / specific implementations, combinations of features from different embodiments / specific implementations are intended to be within the scope of this patent and form different embodiments / specific implementations, as will be understood by those skilled in the art. For example, in the following claims, embodiments / specific implementations of any claim can be used in any combination.

[0105] The terms and expressions used in this specification are for illustrative purposes and not for limitation. Their use is not intended to exclude any equivalents of the shown and described features or portions thereof, but rather to facilitate the understanding that various modifications may be possible within the scope of this patent claim. Therefore, it should be understood that while this patent has been specifically disclosed through preferred embodiments, exemplary embodiments, and optional features, variations or modifications of the concepts disclosed herein may be adopted by those skilled in the art, and such variations and modifications are therefore considered to be within the scope of this patent as defined by the appended claims. The specific embodiments given in this specification are examples of useful embodiments of this patent, and it will be apparent to those skilled in the art that this patent can be implemented using many variations of the devices, device components, and method steps disclosed herein.

[0106] The foregoing description of specific embodiments fully discloses the general features of this patent, enabling others to easily modify and / or adapt such embodiments for various applications by applying knowledge within the scope of the art, without excessive experimentation or deviation from the general concept of this patent. Therefore, based on the teachings and guidance provided herein, it is intended that such modifications and alterations be included within the meaning and scope of equivalents of the disclosed embodiments. It should be understood that the wording or terminology used herein is for descriptive purposes and not intended to be limiting; thus, the wording or terminology in this specification will be interpreted by those skilled in the art based on the foregoing teachings and guidance.

[0107] Furthermore, the scope of this patent should not be limited to any of the exemplary embodiments described above, but only to the appended claims and their equivalents.

Claims

1. A method for detecting and analyzing aromatic components in flue gas, characterized in that, Includes the following steps: Step A: Prepare standard samples; Step B: Prepare smoke traps for tobacco products; Step C: The flue gas collector is diluted with organic solvents at different concentration gradients to obtain the test sample. The fluorescence intensity of the aromatic components in the standard sample and the test sample is obtained by ultraviolet fluorescence spectroscopy. Step D: Based on the fluorescence intensity, identify the sample concentration range where the sample concentration is linearly correlated with the fluorescence intensity; select sample data from the linear concentration range and calculate the concentration of aromatic components in the flue gas using the dilution factor. The formula for calculating the concentration of aromatic components in the flue gas is as follows: Wherein, N is the concentration of aromatic components in the flue gas, in ppm; S m The fluorescence intensity of the sample under test is defined as the concentration gradient m at the same wavelength within the linear concentration range; the S... a S0 represents the fluorescence intensity of the standard solution at the same wavelength; S0 represents the fluorescence intensity of the organic solvent at the same wavelength; X represents... m The dilution factor of the test sample compared to the flue gas trap; where a is the dilution factor of the prepared flue gas trap compared to the mass of flue gas trapped on the Cambridge filter.

2. The method for detecting and analyzing aromatic components in flue gas according to claim 1, characterized in that, In step A, the concentration of the standard sample is 4 to 10 ppm.

3. The method for detecting and analyzing aromatic components in flue gas according to claim 1, characterized in that, Step B includes: Step B-1: Balance the tobacco product and smoke it using the balanced tobacco product; Step B-2: Collect the tobacco product after smoking and process the mainstream smoke or aerosol to obtain the smoke collector.

4. The method for detecting and analyzing aromatic components in flue gas according to claim 3, characterized in that, Specifically, B-1 involves: balancing the tobacco product for 72 hours, then using a smoking machine to inhale the balanced tobacco product in a standard smoking mode to obtain the mainstream smoke or aerosol of the tobacco product. Specifically, B-2 involves: collecting the mainstream flue gas or the aerosol using a Cambridge filter, weighing the mass of the mainstream flue gas or the aerosol before and after collection using the Cambridge filter, and calculating the mass of the mainstream flue gas or the aerosol; diluting the mainstream flue gas or the aerosol at least 50 times using an organic solvent, centrifuging at low temperature, and then extracting the flue gas trap.

5. The method for detecting and analyzing aromatic components in flue gas according to claim 4, characterized in that, The equilibrium temperature of the tobacco product is 21–23°C, and the equilibrium humidity is 57–63%. The organic solvent is anhydrous methanol, a mixture of anhydrous methanol and chloroform, or a mixture of anhydrous methanol and dichloromethane.

6. The method for detecting and analyzing aromatic components in flue gas according to claim 1, characterized in that, In step C, the ultraviolet fluorescence spectroscopy is performed using an ultraviolet fluorescence spectrometer; The constant energy difference between the excitation light and fluorescence during the scanning of the fluorescence spectrometer is 1400 cm⁻¹. -1 Or 2800cm -1 The excitation wavelength scanning range is 200–700 nm; the excitation spectrum scanning speed is 100–300 nm / min. The slit widths of the transmitting and receiving optical paths are the same, either 2.5 nm or 5 nm; the sensitivity of the detection instrument is set to 25-75% of the maximum peak intensity of the detected data.

7. The method for detecting and analyzing aromatic components in flue gas according to claim 1, characterized in that, In step D, the method for screening sample data within the linear concentration range is as follows: The ultraviolet fluorescence spectroscopy method was performed on the solution samples of various concentrations and the organic solvent respectively to obtain the fluorescence spectrum dataset S of the test samples. m and the organic solvent spectrum dataset S0; The peak intensity values ​​of different fluorescence spectra at the same wavelength were compared, and the numerical values ​​(S) were calculated. m+1 -S0 / S m -S0) and (S m -S0 / S m-1 -S0), the filtering results match (S m+1 -S0 / S m -S0)=(m / m+1) and (S m -S0 / S m-1 The data is -S0)<(m-1 / m).

8. The method for detecting and analyzing aromatic components in flue gas according to claim 6, characterized in that, When the excitation wavelength is between 250 and 290 nm, it is a monocyclic aromatic compound; When the excitation wavelength is in the range of 290–320 nm, it is an aromatic compound with two rings; When the excitation wavelength is between 320 and 500 nm, it is a fused-ring aromatic compound with three or more rings.

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