A method for studying the adsorption amount of atomizer in tobacco

Abstract

The present invention provides a method for studying the adsorption amount of an atomizer in tobacco, comprising: selecting tobacco to be tested, introducing an atomizer into the tobacco to be tested using a chemical adsorption instrument to make it adsorbed saturated, and applying an application temperature rise desorption technique to determine the desorption result of the atomizer in the tobacco to be tested. The method for studying the adsorption amount of an atomizer in tobacco of the present invention uses an application temperature rise desorption technique to determine the adsorption and desorption angles of the atomizer on the tobacco surface, and by exploring the adsorption and desorption performance of the atomizer on the tobacco surface, more information about the interaction between the atomizer and the tobacco is obtained.

Description

Technical Field

[0001] The invention relates to the field of tobacco, and in particular to a method for studying the adsorption amount of an atomizer in tobacco. Background Art

[0002] The moisture content of tobacco raw materials is an important indicator that affects sensory comfort. Atomizers are a type of substance that has a strong ability to absorb and retain moisture from the environment. Currently, polyol compounds such as glycerol are the most widely used atomizers in the tobacco industry. Studies have shown that during the smoking process of cigarettes / heated cigarettes, polyol compounds such as glycerol will transfer into the smoke and are positively correlated with the amount of smoke released. At the same time, they will be broken down to produce carbonyl compounds such as formaldehyde, acetaldehyde, propionaldehyde, acrolein, and crotonaldehyde. These carbonyl compounds will irritate the human respiratory system and sensory organs to varying degrees.

[0003] At present, the research on the atomizer content in tobacco mainly determines the percentage of atomizer in tobacco by measuring the mass of tobacco and the mass of added atomizer, and tries to determine the optimal amount of atomizer by not using the percentage of atomizer content. The above method of studying atomizer content is still a macroscopic study, and cannot explore the ability of tobacco to adhere to atomizer content from a more microscopic perspective, nor can it obtain more data information, which hinders the in-depth research and development of atomizers in tobacco. Summary of the invention

[0004] The present invention provides a method for studying the adsorption amount of atomizer in tobacco, so as to solve the above technical problems.

[0005] The present invention provides a method for studying the adsorption amount of an atomizer in tobacco, comprising: selecting tobacco to be tested, introducing an atomizer into the tobacco to be tested using a chemical adsorption instrument to make it adsorbed saturated, and applying an application temperature desorption technology to determine the desorption result of the atomizer in the tobacco to be tested.

[0006] The present invention proposes a research method for the first time, using the application temperature desorption technology to determine the desorption angle of the atomizer on the tobacco surface, and to obtain more information about the interaction between the atomizer and the tobacco by exploring the adsorption and desorption performance of the atomizer on the tobacco surface. The atomizer can be, for example, a polyol compound such as glycerol.

[0007] Programmed temperature desorption is a method of heating an adsorbent that has adsorbed an adsorbate according to a predetermined temperature program (such as constant temperature increase) to obtain a graph showing the relationship between the desorption amount of the adsorbate and the temperature. The present invention utilizes a chemical adsorption instrument and an application temperature desorption technique to investigate the reaction between the adsorbed molecular atomizer and the tobacco solid surface in situ, and can provide a lot of information about the tobacco surface results. The programmed temperature desorption technique is very sensitive to the physical parameters of the adsorbate surface and has a high degree of identification ability. It can be used to study the nature of the effect of the tobacco carrier surface and different atomizers, or the nature of the different tobacco carrier surfaces and atomization.

[0008] The present invention uses a programmed temperature desorption method to establish a detection method for the saturated adsorption amount of the atomizer in the tobacco raw material, the atomizer desorption amount, and the atomizer desorption temperature, and the detection is fast. The experimental results obtained by the programmed temperature desorption method can be used to understand the influencing factors of the saturated adsorption amount of the atomizer, provide a reference for the control of the atomizer content in the tobacco raw material, and also provide more dimensional information and directions for the research and development of tobacco and atomizers.

[0009] For example, the existing improvement directions for tobacco and atomizers are mainly focused on the macroscopic level. Generally, the optimal percentage of atomizer added is adjusted only by taking different amounts of atomizer added and observing the moisture absorption and smoke production of tobacco. The effects of tobacco adsorption capacity, surface characteristics, and atomizer properties on the amount added are not understood. The present invention proposes to use programmed temperature desorption analysis technology to understand the interaction between the atomizer and the tobacco surface, which can explore the effect of the surface conditions of tobacco on the adsorption of the atomizer, and provide data support for research directions such as tobacco surface pore size, specific surface area, and surface modification. In addition, the adsorption rules of atomizers (such as polyol compounds such as glycerol) by tobacco sheets prepared from different process materials can also be clarified.

[0010] Furthermore, the adsorption law of the tobacco to be tested is inferred according to the desorption result. The research method of the present invention on the adsorption amount of the atomizer in tobacco can perform desorption measurement after the atomizer is adsorbed and saturated, thereby obtaining the desorption curve of the atomizer in the tobacco and understanding its desorption law. Since the adsorption and desorption processes are similar, the adsorption law of the tobacco can be inferred according to the desorption curve.

[0011] The chemical adsorption apparatus used for the programmed temperature desorption in the present invention may be a currently commonly used chemical adsorption apparatus, such as a Michael adsorption apparatus.

[0012] Furthermore, when the tobacco to be tested is subjected to adsorption and desorption measurement, the tobacco to be tested will be pretreated, that is, the impurities on the tobacco surface will be removed first. The specific method is: the tobacco to be tested is added to the chemical adsorption instrument, an inert gas is introduced into the tobacco to be tested in the chemical adsorption instrument, and it is heated, so as to remove the impurities adsorbed on the surface of the tobacco to be tested by heating and introducing an inert gas. Afterwards, an inert gas is used as a carrier gas, and the carrier gas carries an atomizer as a pretreatment gas, and the pretreatment gas is introduced into the tobacco to be tested. Specifically, the chemical adsorption instrument includes a Loop sampling tube, and the pretreatment device passes through the Loop sampling tube in the chemical adsorption instrument and then introduces the tobacco to be tested, and the tobacco to be tested adsorbs the atomizer in the pretreatment gas until the adsorption is saturated. Then, the temperature program is started to perform a desorption test. In the temperature program desorption technology, the carrier gas will pass through the U-shaped quartz tube where the tobacco is placed, and the atomizer volatilized by heating in the tube will be taken away by the continuously circulating carrier gas.

[0013] The pretreatment step of the present invention includes impurity removal and adsorption processes, wherein an inert gas is introduced into the tobacco to be tested during impurity removal, and after a period of time, an inert gas and an atomizer are introduced into the tobacco to be tested for an adsorption step, so that the tobacco to be tested is saturated with the atomizer, and then a programmed temperature desorption is performed. The entire pretreatment step including impurity removal and adsorption of the present invention takes 25-40 minutes, preferably 30 minutes, and heating is performed during the entire pretreatment step, and the heating temperature is 140-160° C., preferably 150° C.

[0014] The Loop injection tube in the chemical adsorption instrument is also called a ring-shaped quantitative injection tube. Since the volume is fixed, the volume of the pre-treated gas in each injection is fixed.

[0015] After research, the inventor found that since the volume of the loop injection tube in the chemical adsorption instrument is fixed, the volume of the gas entering the tobacco to be tested through the loop injection tube is fixed each time the sample is injected. In addition, the content of the atomizer carried in the carrier gas is fixed, so the content of the atomizer introduced into the thermal conductivity detector is fixed each time the sample is injected. It can be seen that the content of the atomizer at each injection depends on the volume of the loop injection tube. The existing loop injection tube has a relatively large volume of 5.0 cm 3 , resulting in a small number of injections (1-2 times) reaching injection saturation during the actual measurement process, reducing accuracy and sensitivity, and causing large errors in the measurement results.

[0016] After research and testing, the inventor found that the volume of the Loop injection tube should be modified to 0.5-1cm 3It is more suitable for the determination of the desorption amount of atomizer on the tobacco surface. Specifically, a loop injection tube of appropriate volume can be selected according to the atomizer content of different new tobaccos. Under the premise of maintaining accuracy and sensitivity, the atomizer content that reaches adsorption saturation on the surface of tobacco product materials can be determined by injecting the loop injection tube more than 5-10 times, which provides a simple and effective method for quickly determining the saturated adsorption amount of atomizers on different tobacco raw materials.

[0017] Furthermore, since the loop injection tube is wound around the columnar structure in the chemical adsorption instrument, and both ends of the injection tube are connected to the injection valve, the volume of the loop injection tube can be reduced by shortening the length of the loop injection tube, so that the loop injection tube is modified to 0.5-1cm 3 The volume of the Loop injection tube can be modified by shortening its length without changing other structures in the chemical adsorption instrument. After the length of the Loop injection tube is reduced, the number of turns wound around the cylindrical structure can be reduced, which makes modification convenient.

[0018] Specifically, the method for studying the adsorption amount of atomizer in tobacco of the present invention comprises the following steps: pretreatment: adding the tobacco to be tested into a chemical adsorption instrument, heating it, introducing an inert gas into the tobacco to be tested for impurity removal, and then using the inert gas as a carrier gas, and using the carrier gas to carry the atomizer as a pretreatment gas, and the pretreatment gas is introduced into the tobacco to be tested through the Loop injection tube in the chemical adsorption instrument, so that the tobacco to be tested reaches adsorption equilibrium; desorption treatment: in an inert gas atmosphere, the adsorbed tobacco to be tested is subjected to a desorption treatment to obtain a desorption curve of the tobacco to be tested. For example, in the programmed temperature desorption technology, the carrier gas will pass through a U-shaped quartz tube where the tobacco is placed, and the atomizer volatilized by heating in the tube will be taken away by the continuously flowing carrier gas.

[0019] Furthermore, the pretreatment temperature is 145-155° C., preferably 150° C., and the pretreatment time is 25-35 min, preferably 30 min.

[0020] Furthermore, the temperature of the desorption treatment is 180-250° C., preferably 200° C.; and the time of the desorption treatment is 90-150 min.

[0021] The present invention calculates the saturated adsorption amount of the atomizer on the tobacco to be tested according to the adsorption equilibrium of the tobacco to be tested. After the saturated adsorption amount is obtained, a desorption test can be performed to obtain a desorption curve.

[0022] Furthermore, the above-mentioned inert gas (ie, carrier gas) can be selected from nitrogen or helium. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a chemical adsorption apparatus according to a specific embodiment of the present invention is shown;

[0024] Figure 2 A schematic diagram showing an improved Loop injection tube according to a specific embodiment of the present invention is shown;

[0025] Figure 3 A schematic diagram of the connection of the Loop injection tube in a specific embodiment of the present invention is shown;

[0026] Figure 4 The curve showing the change of desorption glycerol over time during the programmed temperature desorption process of the monoclinic tobacco sample obtained in Example 1;

[0027] Figure 5 The curve of desorption of glycerol over time during the programmed temperature desorption process of the monoclinic tobacco sample obtained in Example 2 is shown. DETAILED DESCRIPTION

[0028] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may extend based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0029] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0030] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] Figure 1 shows a schematic diagram of a chemical adsorption apparatus, Figure 2 The figure shows the improved schematic diagram of the Loop injection tube. Figure 1 and Figure 2 , in the preprocessing step, Figure 1The intermediate treatment gas is the gas that enters the reaction tube during the pretreatment process. It is an inert gas and is used for impurity removal in the pretreatment step. The present invention can be done without a cold trap or with a cold trap. The function of the cold trap is that in the impurity removal step, the inert gas will carry out impurities in the tobacco after passing through the tobacco to be tested, and then the impurities can be adsorbed by the cold trap. In the adsorption process in the pretreatment, the carrier gas and the atomizer are passed through the six-way valve together by pulse gas into the tobacco to be tested, and the process of tobacco adsorbing the atomizer is carried out. After the adsorption is saturated, the subsequent programmed temperature desorption test is carried out.

[0032] In the desorption treatment step, the pulse gas is a gas, such as helium, that brings the atomizer volatilized at high temperature in the reaction tube heated in the high temperature furnace into the Loop injection tube. When performing the injection operation, the Loop injection tube is connected to the six-way valve, wherein the pulse gas inlet is connected to the reaction gas inlet, one end of the Loop injection tube is connected to the pulse gas inlet, and the other end is connected to the reaction gas inlet. The atomizer volatilized at high temperature in the reaction tube is injected into the Loop ring by the pulse air inlet. After the Loop ring is full, the Loop ring is connected to the reaction air inlet, and the reaction gas transported by the pipeline pushes the volatilized atomizer into the thermal conductivity detector (TCD detector) for analysis.

[0033] The reaction gas is the gas that enters the reaction tube during the desorption process, such as helium. In other embodiments, other gases that can undergo chemical reactions can also be used as reaction gases to explore other properties of the tobacco in the reaction tube, which can be used as subsequent further research work.

[0034] Figure 3 A schematic diagram of the connection of the Loop injection tube is shown. The Loop injection tube is wound around the cylindrical structure, and the two ends extending after winding are connected to the injection valve through fixing nuts. The annular shell is sleeved on the outer periphery of the cylindrical structure and fixed by an annular nut. The Loop injection tube of this embodiment is installed in the valve cover on the top of the chemical adsorption instrument, fixed to the mounting plate by an annular nut, and the periphery is protected by the annular shell. The two ends of the ring are connected to the injection valve with temperature control. The Loop injection tube can be replaced according to the need for adsorption. For example, it can be replaced with a Loop injection tube with a reduced length. The specific operation method is:

[0035] 1) Make sure the instrument is at room temperature. You can use manual control to set the heating zone temperature to room temperature and wait for the instrument to cool down.

[0036] 2) Unscrew the screws on the upper cover of the chemical adsorption instrument, remove the upper cover, and the front cover can be pulled forward.

[0037] 3) Pull out the two fixing bolts of the valve cover and lift the valve cover upwards to remove it.

[0038] 4) Remove the valve insulation.

[0039] 5) Unscrew the ring nut, remove the ring shell, and loosen the middle screw of the Loop injection tube to remove the Loop injection tube.

[0040] 6) Use a wrench to loosen the ferrule at the head of the Loop injection tube.

[0041] 7) Pull up the loop injection tube to remove it from the mounting plate.

[0042] 8) Install the new Loop injection tube, connect both ends of the injection tube to the injection valve, and tighten the ring shell 2 with your fingers.

[0043] 9) Press the Loop injection tube into place so that it contacts the mounting plate.

[0044] 10) Tighten the fixing screw of the Loop injection tube.

[0045] 11) Tighten the screws on the housing to secure the new Loop injection tube.

[0046] 12) Reinstall the insulation and valve cover.

[0047] 13) Push up the front panel of the chemical adsorption instrument and close the upper cover.

[0048] 14) After installing the loop, recalibrate the loop injection tube to determine the actual volume of the new loop injection tube.

[0049] Example 1

[0050] Monoclinic tobacco (Hunan C-picked) samples were used as the tobacco to be tested. The samples were cleaned at 100°C in a N2 atmosphere, and then glycerol was introduced for adsorption. The entire pretreatment process took 30 minutes. The samples were naturally cooled to 30°C in the sample tube, and then heated to 200°C at a heating rate of 10°C / min in a N2 atmosphere, and kept at 200°C for 90 minutes. Figure 4 It can be seen that the glycerol on the surface of the material begins to desorb significantly at 200°C, and an obvious desorption peak appears after desorption at 200°C for 90 minutes.

[0051] According to Example 1, it can be found that when desorbed at 200°C for 90 minutes, an obvious desorption peak appears, but the signal peak of the glycerol thermal conductivity detector TCD is weak at this time, so it is necessary to extend the desorption time to continue the measurement. In addition, glycerol has high viscosity, and the desorbed glycerol is easily adsorbed in the pipeline of the instrument, so it is necessary to increase the pretreatment temperature.

[0052] Example 2

[0053] Still taking the monoclinic tobacco sample as an example, the pretreatment and desorption methods are the same as those in Example 1, except that the pretreatment temperature is increased to 150° C., and the temperature is increased to 200° C. and maintained for 120 min during the desorption test.

[0054] from Figure 5 It can be seen that the first desorption peak of the sample begins to appear when the temperature is programmed to 180°C, the peak is completed at 20 minutes, the second desorption peak appears at 40-60 minutes, the peak is completed at 100 minutes, and the third desorption peak appears at 100-140 minutes. This shows that there are three adsorption modes of glycerol adsorption on the sample surface. The first two glycerol desorption peaks are physical adsorption of glycerol on its surface, and the third desorption peak corresponds to chemical adsorption of glycerol.

[0055] According to the above examples, it can be found that by performing chemical adsorption and desorption measurement on tobacco samples, a variety of information can be obtained, and the specific effects are as follows:

[0056] (1) The saturated adsorption capacity of polyol compounds such as glycerol by different tobacco raw material sheets is measured by a modified chemical adsorption instrument to determine when the adsorption reaches equilibrium. The saturated adsorption capacity of polyol compounds such as glycerol by different tobacco raw material sheets is calculated by data fitting.

[0057] (2) The adsorption and desorption equilibrium of polyol compounds such as glycerol on different tobacco raw material sheets was measured and calculated by using the modified chemical adsorption instrument, and the adsorption amount of polyol compounds such as glycerol on tobacco raw material materials under normal temperature and pressure was measured.

[0058] (3) The modified chemical adsorption instrument was used to measure the change in the desorption amount of polyol compounds such as glycerol adsorbed on the surface of tobacco product materials during the programmed temperature rise from 30°C to 350°C. The adsorption strength of polyol compounds such as glycerol on the surface of tobacco materials was determined, and the relationship between the adsorption and desorption of polyol compounds such as glycerol on the surface of tobacco raw materials was analyzed.

[0059] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A method for studying the adsorption amount of atomizer in tobacco, characterized in that: include: Select tobacco to be tested, use a chemical adsorption instrument to introduce an atomizer into the tobacco to make it adsorbed saturated, use an application temperature desorption technique to measure the desorption result of the atomizer in the tobacco to be tested, infer the adsorption law of the atomizer in the tobacco to be tested based on the desorption result, and obtain information on the interaction between the atomizer and the tobacco. The original loop injection tube in the chemical adsorption instrument was modified to shorten the length of the loop injection tube so that the volume of the loop injection tube was reduced to 0.5-1 cm 3 , the volume of the Loop injection tube is modified to 0.5-1cm 3 It is more suitable for the determination of the desorption amount of atomizer on the tobacco surface. The research method specifically comprises the following steps: Pretreatment: adding the tobacco to be tested into the chemical adsorption instrument, heating it, introducing an inert gas into the tobacco to be tested to remove impurities, then using the inert gas as a carrier gas, and using the carrier gas to carry an atomizer as a pretreatment gas, and introducing the pretreatment gas into the tobacco to be tested through a loop injection tube in the chemical adsorption instrument, so that the tobacco to be tested reaches adsorption equilibrium; Desorption treatment: in an inert gas atmosphere, the adsorbed tobacco to be tested is subjected to desorption treatment to obtain a desorption curve of the tobacco to be tested.

2. The method for studying the amount of atomizer adsorption in tobacco according to claim 1, characterized in that: The pretreatment temperature is 145-155° C., and the pretreatment time is 25-35 min.

3. The method for studying the amount of atomizer adsorption in tobacco according to claim 1, characterized in that: The temperature of the desorption treatment is 180-250° C., and the time of the desorption treatment is 90-150 min.

4. The method for studying the amount of atomizer adsorption in tobacco according to claim 1, characterized in that: The saturated adsorption amount of the atomizer on the tobacco to be tested is calculated according to the adsorption equilibrium of the tobacco to be tested.

5. The method for studying the amount of atomizer adsorption in tobacco according to claim 1, characterized in that: The inert gas is nitrogen or helium.

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