A prediction method for the adsorption of aroma raw materials on tobacco biochar

Abstract

The present invention discloses a prediction method for adsorption of aroma raw materials on tobacco biochar, comprising the following steps: (1) preparing tobacco biochar by heating tobacco at a temperature when cigarettes are used; (2) determining the types and contents of elements in tobacco biochar by elemental composition analysis; (3) determining the types of characteristic functional groups in tobacco biochar by Fourier infrared spectroscopy analysis; (4) determining the proportion of chemical bonds or characteristic functional groups in tobacco biochar by X-ray photoelectron spectroscopy analysis; (5) constructing a tobacco biochar model and optimizing the model; (6) predicting the adsorption of aroma raw materials on tobacco biochar. The method of the present invention uses computer simulation prediction technology for the first time to explore the release and adsorption mechanism of aroma raw materials for tobacco on tobacco biochar, providing theoretical support for in-depth understanding of the interception and release of aroma raw materials on cigarettes after burning, while avoiding a large amount of experimental work, saving research time, and reducing solvent pollution.

Description

Technical Field

[0001] The invention belongs to the technical field of tobacco, and in particular relates to a prediction method based on the adsorption of aroma raw materials on tobacco biochar. Background Art

[0002] Tobacco flavors are indispensable additives added to cigarettes during the production process. They play an extremely important role in modifying, supplementing and highlighting the original aroma and flavor of high-quality tobacco leaves, and help to form and highlight the style characteristics of cigarettes. Most flavors are added to shredded tobacco and then transferred to the smoke through heating or burning. Therefore, the study of the release and transfer behavior of flavors in cigarette tobacco is crucial.

[0003] At present, the release and transfer of flavors in cigarette tobacco is mainly studied by capturing mainstream smoke through Cambridge filters, extracting and analyzing it with gas chromatography-mass spectrometry, and then calculating the conversion rate to summarize the release rules of various flavor raw materials. The rules obtained by the existing methods are only superficial phenomena, and the experimental workload is large, the research cycle is long, and it is difficult to timely feedback the transfer rules of flavors in tobacco biochar and design and apply cigarette products in a timely manner.

[0004] The present invention has been proposed to solve the above-mentioned problems. Summary of the invention

[0005] The present invention provides a method for constructing a tobacco biochar model based on molecular dynamics and the established biochar model is used to predict the qualitative and quantitative conditions of adsorption of aromatic raw materials on biochar.

[0006] The technical solution of the present invention is as follows:

[0007] A method for predicting the adsorption of aromatic raw materials on tobacco biochar comprises the following steps:

[0008] (1) heating tobacco at a temperature when cigarettes are used to prepare tobacco biochar;

[0009] (2) Determine the types and contents of elements in tobacco biochar through elemental composition analysis;

[0010] (3) Determine the types of characteristic functional groups in tobacco biochar by Fourier transform infrared spectroscopy analysis;

[0011] (4) Determine the proportion of chemical bonds or characteristic functional groups in tobacco biochar by X-ray photoelectron spectroscopy analysis;

[0012] (5) Construct tobacco biochar model and optimize the model;

[0013] (6) Using the biochar model of (5), molecular dynamics simulation calculations are performed on the tobacco biochar prepared in step (1) and different aroma raw materials to obtain an adsorption equilibrium configuration diagram, thereby predicting the adsorption of aroma raw materials on the tobacco biochar.

[0014] Preferably, the tobacco biochar in step (1) includes biochar produced by heating or burning heated cigarettes, or biochar produced by heating or burning traditional cigarettes.

[0015] Preferably, the element content in the tobacco biochar in step (2) refers to the mass ratio or molar ratio of each element.

[0016] Preferably, the Fourier transform infrared spectroscopy analysis in step (3) is mainly performed for C element morphology analysis; the main functional groups are judged according to the attribution of characteristic absorption peaks of the infrared spectrum of tobacco biochar, the absorption peak position (3600-3300) is the strong and broadly associated stretching vibration of alcoholic hydroxyl and phenolic hydroxyl -OH, the absorption peak position (2910-2930) is the asymmetric stretching vibration of -CH2 of aliphatic, the absorption peak position (2845-2860) is the symmetric stretching vibration of -CH2 of aliphatic, and the absorption peak position (2845-2860) is the symmetric stretching vibration of -CH2 of aliphatic. The position (1720-1735) is the -C=O stretching vibration of the carboxyl and carbonyl functional groups, the absorption peak position (1590-1650) is the C=C vibration of the aromatic ring skeleton and the O=CN stretching vibration of the amide bond, the absorption peak position (1395-1420) is the OH bending vibration of alcohols or carboxylic acids and the CO stretching vibration of phenols, the absorption peak position (1150-1315) is the -COC stretching vibration, and the absorption peak position (1015-1030) is the -CC lipid skeleton vibration.

[0017] Preferably, the X-ray photoelectron spectroscopy analysis in step (4) mainly includes C element morphology analysis and O element morphology analysis, and the percentage of chemical bonds or functional groups at different peak positions to the total number of C atoms and O atoms is calculated by calculating the percentage of the peak area of ​​each characteristic peak to the total peak area; C atoms mainly exist in the form of CC and C=C, and a small part is combined with oxygen, hydrogen or nitrogen to form CO, CH, C=O, O=CO or O=CN; O atoms mainly exist in the form of C=O and CO, and another small part exists in the form of O=CO.

[0018] Preferably, step (5) uses the Visualizer module in Materials Studio 2017R2 software to construct a tobacco biochar model, such as The tobacco biochar model was then optimized using the Forcite module in MS.

[0019] Preferably, in step (6), the Forcite module of Materials Studio software is used to perform molecular dynamics simulation analysis, and the box size of the molecular dynamics simulation is The middle of the box is the biochar adsorbent layer; the adsorption of aroma raw materials on tobacco biochar is predicted based on the number of oxygen molecules, nitrogen molecules and characteristic aroma raw material molecules contained in the upper and lower areas of the box.

[0020] Preferably, the molecular dynamics simulation uses NVT ensemble and COMPASSⅡ force field, van der Waals force and Coulomb force are described by Ewald method, the temperature is set to 298K, the duration of each step is 1fs, the total simulation time is 1ns, and 5000 steps are used as one frame for result output; the last 500ps trajectory file is taken for adsorption equilibrium configuration analysis.

[0021] Preferably, the adsorption capacity of tobacco biochar for aroma raw materials is predicted based on the distribution mode, sparse distribution or aggregation of different aroma raw material molecules on the biochar model.

[0022] Beneficial effects of the present invention:

[0023] 1. This invention uses computer simulation prediction technology for the first time to explore the release and adsorption mechanism of tobacco flavor raw materials on tobacco biochar, providing theoretical support for a deep understanding of the interception and release of flavor raw materials on cigarettes after burning; avoiding a lot of experimental work, saving research time, and reducing solvent pollution.

[0024] 2. The method of the present invention can predict the migration and release behavior of flavor raw materials, realize the comparison of the migration and release rules of various flavor raw materials on tobacco biochar and make preliminary screening, guide the selection of tobacco flavor raw materials, and scientifically design flavor formulas from the perspective of maximum utilization rate and optimal style formation. For heated cigarettes, it can also guide the heating temperature of smoking utensils and design smoking utensils more reasonably according to the flavor formula. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the Fourier infrared spectroscopy analysis spectrum of the tobacco biochar prepared in the example.

[0026] Figure 2 and Figure 3 The C spectrum and O spectrum obtained by X-ray photoelectron spectroscopy analysis of the tobacco biochar prepared in Example.

[0027] Figure 4 Tobacco biochar model constructed for the examples.

[0028] Figure 5 This is the adsorption equilibrium configuration diagram of different aroma raw materials on the tobacco biochar model constructed in the example. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0030] Example

[0031] The steps for constructing the tobacco biochar model are as follows:

[0032] 1. Use the central heating smoking device to smoke cigarettes in the normal way, and select the carbonized tobacco as the experimental object.

[0033] 2. Determine the types and contents of elements in tobacco biochar through elemental composition analysis;

[0034] 3. Determine the types of characteristic functional groups in tobacco biochar by Fourier transform infrared spectroscopy analysis;

[0035] 4. Determine the proportion of chemical bonds or characteristic functional groups in tobacco biochar by X-ray photoelectron spectroscopy analysis;

[0036] 5. Construct tobacco biochar model and optimize the model through material simulation and modeling software.

[0037] In this embodiment, the heating method of the heated cigarette is central heating, the heating temperature is 380° C., and the elemental composition analysis of the carbonized tobacco is shown in Table 1:

[0038] Table 1 Mass content and molar ratio of each element in tobacco biochar heated at 380℃

[0039]

[0040] Figure 1 This is the Fourier infrared spectrum analysis of tobacco biochar, at 3298cm -1 、2913cm -1 、1604cm -1 、1371cm -1 、1314cm -1 、1155cm -1 and 1021cm -1 There are characteristic peaks at the bottom. According to the attribution of characteristic absorption peaks in the infrared spectrum, it can be seen that the tobacco biochar mainly contains functional groups such as hydroxyl, carboxyl, and carbonyl. Aromatic hydrocarbon compounds and ester compounds may be formed during the central heating process of the tobacco, which decompose to form alcohols or phenolic compounds containing -OH groups.

[0041] Figure 2This is the C spectrum obtained by X-ray photoelectron spectroscopy analysis of tobacco biochar. It can be seen from the figure that the C atom at 284.68eV exists in the form of CC (H) or C = C, the peak at 286.17eV is CO or CN group (such as alcohol, amine or amide), the C atom at 287.21eV combines with O to form C = O bond or OCO functional group (such as aldehyde, amide, carboxylic acid), and the C atom at 288.13eV combines with O to exist in the form of OC = O (such as carboxyl group or ester functional group). By calculating the percentage of each characteristic peak area to the total peak area, the percentage of chemical bonds or functional groups at different peak positions to the total number of C atoms can be obtained, as shown in Table 2. It can be seen from the table that C atoms mainly exist in the form of CC and C = C, and a small part combines with oxygen, hydrogen or nitrogen to form CO, CH, C = O, O = CO or O = CN.

[0042] Table 2 Existence forms and proportions of C elements in tobacco biochar

[0043]

[0044] Figure 3 This is the O spectrum obtained by X-ray photoelectron spectroscopy analysis of tobacco biochar. It can be seen from the figure that at 531.41eV, O atoms combine with C to form C=O bonds or OCO functional groups (such as aldehydes, amides, carboxylic acids), the peak at 532.56eV is CO or CN groups (such as alcohols, phenols or amide groups), and at 533.35eV, O atoms combine with C in the form of OC=O (such as carboxyl groups or ester functional groups). By calculating the percentage of each characteristic peak area to the total peak area, the percentage of chemical bonds or functional groups at different peak positions to the total number of O atoms can be obtained, as shown in Table 3. It can be seen from the table that O atoms mainly exist in the form of C=O and CO, and another small part is in the form of OC=O.

[0045] Table 3 Existence forms and proportions of O element in tobacco biochar

[0046]

[0047] Built with the Visualizer module in Materials Studio 2017R2 The tobacco biochar model was then optimized using the Forcite module in MS to obtain the final model structure as shown in Figure 4 shown.

[0048] Prediction of adsorption of aroma raw materials using tobacco biochar model.

[0049] The biochar model obtained above is used to predict the adsorption of anisaldehyde and β-ionone on it. The Forcite module of Materials Studio software is used for molecular dynamics simulation analysis. The molecular level is analyzed to obtain adsorption equilibrium configuration information. Combined with the results of traditional experiments, the mechanism of the influence of tobacco and filter materials on the release of fragrance raw materials during heating is analyzed. The box size of the molecular dynamics simulation is The middle of the box is the adsorbent layer, and the upper and lower areas of the box contain 96 oxygen molecules, 384 nitrogen molecules, and 20 characteristic aroma raw material molecules. Molecular dynamics simulation uses NVT ensemble and COMPASSⅡ force field, van der Waals force and Coulomb force are described by Ewald method, the temperature is set to 298K, each step is 1fs, the total simulation time is 1ns, and 5000 steps are one frame for result output. The last 500ps trajectory file is taken for adsorption equilibrium configuration result analysis.

[0050] Figure 5 It shows the adsorption equilibrium configuration of two different aroma raw materials, anisaldehyde and β-ionone, on the tobacco biochar model under the central heating mode of 380℃. It can be seen from the figure that both flavors are relatively evenly distributed on the upper and lower surfaces of the tobacco biochar model, among which β-ionone can be more concentratedly and tightly adsorbed on the surface of the biochar model, while anisaldehyde is more sparsely distributed on the surface of the biochar model; thus, it can be seen that the residual β-ionone in the tobacco after the cigarette is smoked is higher than that of anisaldehyde.

[0051] Experiment on the actual adsorption of aromatic raw materials on tobacco biochar.

[0052] The same heated cigarette as in Example 1 was added with two flavor raw materials, p-anisaldehyde and β-ionone, and smoked at 380°C. After smoking, the residual amount and residual rate of the two flavor raw materials in the tobacco were measured. The results showed that the residual rate of p-anisaldehyde was 1.904%, and the residual rate of β-ionone was 3.175%; the residual rate of β-ionone in the tobacco was higher than that of p-anisaldehyde, which was consistent with the result predicted by the prediction method of the present invention.

[0053] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for predicting the adsorption of aromatic raw materials on tobacco biochar, characterized in that: The steps include: (1) heating tobacco at a temperature when cigarettes are used to prepare tobacco biochar; (2) Determine the types and contents of elements in tobacco biochar through elemental composition analysis; (3) Determine the types of characteristic functional groups in tobacco biochar by Fourier transform infrared spectroscopy analysis; (4) Determine the proportion of chemical bonds or characteristic functional groups in tobacco biochar by X-ray photoelectron spectroscopy analysis; (5) Construct tobacco biochar model and optimize the model; (6) using the biochar model of (5) to perform molecular dynamics simulation calculations on the tobacco biochar prepared in step (1) and different aroma raw materials to obtain an adsorption equilibrium configuration diagram, thereby predicting the adsorption of aroma raw materials on the tobacco biochar; Step (4) X-ray photoelectron spectroscopy analysis mainly includes C element morphology analysis and O element morphology analysis, and the percentage of chemical bonds or functional groups at different peak positions to the total number of C atoms and O atoms is calculated by calculating the percentage of the peak area of ​​each characteristic peak to the total peak area; Step (5) Use the Visualizer module in Materials Studio 2017R2 software to build the tobacco biochar model, and then use the Forcite module in MS to optimize the model; Step (6) uses the Forcite module of Materials Studio software to perform molecular dynamics simulation analysis. The box size of the molecular dynamics simulation is The middle of the box is a biochar adsorbent layer; the adsorption of aroma raw materials on tobacco biochar is predicted based on the number of oxygen molecules, nitrogen molecules and characteristic aroma raw material molecules contained in the upper and lower areas of the box; The molecular dynamics simulation used the NVT ensemble and COMPASSⅡ force field. The van der Waals force and Coulomb force were described by the Ewald method. The temperature was set to 298K, the duration of each step was 1fs, the total simulation time was 1ns, and 5000 steps were used as one frame for result output. The trajectory file after 500ps was taken for adsorption equilibrium configuration analysis.

2. The prediction method according to claim 1, characterized in that: The tobacco biochar in step (1) includes biochar produced by heating or burning heated cigarettes, or biochar produced by heating or burning traditional cigarettes.

3. The prediction method according to claim 1, characterized in that: The element content in the tobacco biochar in step (2) refers to the mass ratio or molar ratio of each element.

4. The prediction method according to claim 1, characterized in that: Step (3) Fourier transform infrared spectroscopy analysis is mainly performed for C element morphology analysis.

5. The prediction method according to claim 1, characterized in that: The adsorption capacity of tobacco biochar for aroma raw materials is predicted based on the distribution mode, sparse distribution or aggregation of different aroma raw material molecules on the biochar model.

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