Heat-not-burn smoke-generating particles and preparation method thereof

Abstract

The present invention discloses a heat-not-burn smoke-generating particle and a preparation method thereof, relating to the technical field of heated cigarettes. The heat-not-burn smoke-generating particle of the present invention uses modified activated carbon as a carrier and is composited with a flavoring agent, an atomizer, and auxiliary materials. The modified activated carbon is composited with activated carbon particles and silicon nitride nanosheets, and the modified activated carbon has a hierarchical porous structure. The present invention discloses a heat-not-burn smoke-generating particle using modified activated carbon as a carrier. The particle is capable of effectively loading a flavoring agent and an atomizer, and has good thermal conductivity, which can ensure, to a certain extent, uniform heating of the smoke particle as a whole, thereby ensuring an atomization effect and, in turn, a good smoking experience.

Description

Technical Field

[0001] The present invention relates to the technical field of heated cigarettes, and in particular to heat-not-burn cigarette smoke particles and a preparation method thereof. Background Art

[0002] This year, with consumers' growing concern about smoking and health, and increasing efforts to ban smoking in public places, sales of traditional tobacco products are facing a turning point. However, new tobacco products that meet consumers' health needs, particularly heat-not-burn (HNB) cigarettes, are rapidly gaining popularity. HNB cigarettes are made by heating tobacco with an electronic heating device without burning it. The principle is that the tobacco absorbs external heat from the heating device, raising its temperature and releasing smoke.

[0003] At present, the raw materials used for the cores of heat-not-burn cigarettes are mainly glycerin-containing tobacco, reconstituted tobacco leaves and smoke-generating particles. Among them, the smoke-generating particles are mostly made of a compound of a carrier, an atomizer, tobacco particles, etc. During use, the position in contact with the heating device is heated, and then the heat is transmitted to the inside of the smoke-generating particles, causing the atomizer to change from liquid to gas and release smoke. However, since most existing carriers use plant-derived particles, bentonite and other materials, due to their poor thermal conductivity, the smoke-generating particles will be heated unevenly, which will lead to uneven release of the atomizer, affecting the taste of smoking. Summary of the Invention

[0004] In response to the above problems, the purpose of the present invention is to disclose a heat-not-burn smoke-generating particle and a preparation method thereof, which uses modified activated carbon as a carrier, can better load the flavoring agent and the atomizer, and has good thermal conductivity, which can ensure the uniformity of the overall heating of the smoke-generating particles to a certain extent, thereby ensuring the atomization effect and further ensuring the taste of the smoke.

[0005] Specifically, the present invention provides a heat-not-burn smoke-generating particle, which is composited with modified activated carbon as a carrier, a flavoring agent, an atomizer, and auxiliary materials. The modified activated carbon is composited with activated carbon particles and silicon nitride nanosheets.

[0006] Furthermore, the modified activated carbon has a hierarchical porous structure.

[0007] Furthermore, the mass ratio of the modified activated carbon, the fragrance generating agent, the atomizer and the auxiliary materials is 3:(0.8-1):(0.5-1):(6-8).

[0008] Furthermore, the preparation method of the modified activated carbon is as follows: silicon nitride nanosheets are added to deionized water, ultrasonically dispersed for 1-2 hours to obtain a silicon nitride dispersion, resorcinol and hexadecyltrimethylammonium bromide are weighed and stirred and dissolved in a 40-50% volume fraction ethanol solution, 25wt% ammonia solution is added dropwise, stirred and mixed for 25-30 minutes, chitosan solution and silicon nitride dispersion are added, stirred and mixed for 30 minutes, formaldehyde solution is added dropwise, and stirring is continued for 20-25 hours after the addition is completed, freeze-dried, and the solid is heated to 850-900°C at a rate of 1-2°C / min under a nitrogen atmosphere, kept warm for 2-3 hours, naturally cooled to room temperature, taken out and ground to obtain modified activated carbon.

[0009] Furthermore, the particle size of the modified activated carbon is 120-350 μm.

[0010] Furthermore, the auxiliary material is any one of tobacco powder and natural plant powder.

[0011] In addition, the present invention also discloses a method for preparing the above-mentioned suction particles, which comprises the following steps:

[0012] S1: Place the pretreated modified activated carbon on a tray and dry it at 40-60°C for 15-30 minutes. Then, add it to the disc while it is still hot. While the disc is rotating, spray the atomizer and fragrance-generating agent intermittently and alternately 3-5 times to obtain premixed particles.

[0013] S2: Place 1 / 2 of the premixed granules in a disc and spray with adhesive;

[0014] S3: After stirring and mixing, add auxiliary materials and stir and mix;

[0015] S4: Add the fragrance generating agent into the disc and stir to mix;

[0016] S5: Add the remaining premixed particles in batches, repeat steps S3-S5, roll into particles, and dry;

[0017] S6: Sieve the dried particles to select particles with a particle size of 20-30 mesh to obtain suction particles.

[0018] Furthermore, in step S2, the mass of the added binder is 1%-3% of the mass of the premixed particles.

[0019] Furthermore, the pretreatment of the modified activated carbon is as follows: after the modified activated carbon is cleaned and dried, an adhesive is sprayed on the surface of the modified activated carbon, and the modified activated carbon is placed in kapok short fibers, a kapok short fiber layer is wrapped on the surface of the modified activated carbon, and then semi-carbonized under an inert atmosphere. After the treatment is completed, the semi-carbonized kapok short fiber layer is placed in a low-temperature plasma reactor and treated with low-temperature plasma using air as the working gas.

[0020] Furthermore, the temperature of the semi-carbonization treatment is 310-350° C., and the treatment time is 20-30 minutes.

[0021] Furthermore, the low-temperature plasma treatment uses air as the working gas, the power is 300 W, and the gas flow rate is 50 L / min.

[0022] Furthermore, the adhesive is a composite adhesive, which includes component A and component B in a mass ratio of 1:(2-8), wherein component A is a chitosan compound, and component B is one or more of hydroxymethyl methylcellulose, hydroxypropyl methylcellulose, and hydroxyethyl methylcellulose.

[0023] Furthermore, the atomizer is one or more of glycerol, modified glycerol, and a novel atomizer, wherein the modified glycerol and the novel atomizer can be any existing atomizer, and thus will not be described in detail.

[0024] Beneficial effects of the present invention:

[0025] 1. The present invention discloses a heat-not-burn smoke-generating particle, which uses modified activated carbon as a carrier. The modified activated carbon is formed into a three-dimensional network structure gel by chitosan and hexadecyltrimethylammonium bromide, and silicon nitride nanosheets are wrapped inside. After high-temperature carbonization, a hierarchically porous activated carbon / silicon nitride nanosheet composite structure is formed. Among them, the activated carbon itself has good thermal conductivity, but the hardness is not high. By compounding the silicon nitride nanosheets with the modified activated carbon, on the one hand, the silicon nitride nanosheets can improve the internal structure of the modified activated carbon and the modified activated carbon particles. The thermal conductivity between the particles is improved, so that to a certain extent, the flavoring agent and atomizer loaded thereon can be heated evenly, thereby ensuring the taste of the puff. On the other hand, the addition of silicon nitride nanosheets can improve the pressure-bearing capacity of the entire modified activated carbon particles to a certain extent, and the addition of silicon nitride nanosheets will also form a macroporous structure between the silicon nitride nanosheets, so that the entire modified activated carbon particles have a hierarchical porous structure. Compared with the direct use of activated carbon, it has a larger surface area and better adsorption capacity, and can better adsorb flavoring agents and atomizers.

[0026] 2. The heat-not-burn smoke-generating particles of the present invention are pretreated before use by pre-treating the modified activated carbon and wrapping a layer of kapok short fibers on the surface of the modified activated carbon. Since the kapok short fibers have good lipophilicity, they can improve the loading capacity of the modified activated carbon for flavoring agents and atomizers to a certain extent. The kapok short fibers are semi-carbonized to form pores on the surface of the kapok short fibers, thereby further improving the loading capacity and hardening the surface of the kapok short fibers. Low-temperature plasma treatment is then used to bombard the surface of the semi-carbonized kapok short fibers with plasma, and partially peel off the carbonized parts of the kapok short fibers. On the one hand, voids are formed and the surface of the kapok short fibers is made rougher, which is more conducive to the loading of the modified activated carbon. On the other hand, part of the kapok short fibers are exposed, resulting in a better adsorption effect. DETAILED DESCRIPTION

[0027] The present invention will be described in detail below with reference to specific embodiments:

[0028] The present invention discloses a heat-not-burn smoke-generating particle, which is composited with modified activated carbon as a carrier, a flavoring agent, an atomizer, and auxiliary materials. The modified activated carbon is composited with activated carbon particles and silicon nitride nanosheets, and has a hierarchical porous structure.

[0029] The details are as follows:

[0030] Example 1

[0031] Preparation of modified activated carbon

[0032] Silicon nitride nanosheets were added to deionized water at a solid-liquid ratio of 15 g / L and ultrasonically dispersed for 2 h to obtain a silicon nitride dispersion. Resorcinol and hexadecyltrimethylammonium bromide were weighed in a mass ratio of 1:3 and stirred and dissolved in a 40% ethanol solution. The mass ratio of ethanol solution to hexadecyltrimethylammonium bromide was 50:1. A 25 wt% ammonia solution with the same mass of resorcinol was added dropwise and stirred for 28 min. Then, 2 wt% chitosan solution and silicon nitride dispersion were added. The mixture was prepared by stirring for 30 minutes, adding formaldehyde solution with the same volume of ammonia solution, and continuously stirring for 20 hours after the addition was completed. The mixture was freeze-dried to obtain a solid. The temperature was raised to 900°C at a rate of 2°C / min under a nitrogen atmosphere and kept for 2 hours. The solid was naturally cooled to room temperature, and then taken out and ground to obtain a modified activated carbon with a hierarchical porous structure. The average particle size of the modified activated carbon was 135 μm.

[0033] The prepared modified activated carbon is used to prepare smoke particles, specifically as follows:

[0034] Preprocessing

[0035] After cleaning and drying the modified activated carbon, an adhesive was sprayed onto the surface of the modified activated carbon. The adhesive in this embodiment was prepared by stirring potassium silicate and ethyl cellulose in a mass ratio of 2:8. The mass of the added adhesive was 2% of the mass of the modified activated carbon. The modified activated carbon was placed in kapok staple fibers, and a kapok staple fiber layer was wrapped on the surface of the modified activated carbon. Then, under an inert atmosphere, a semi-carbonization treatment was performed at a temperature of 310°C for 25 minutes. After the treatment was completed, the semi-carbonized kapok staple fiber layer was placed in a low-temperature plasma reactor and subjected to low-temperature plasma treatment at a power of 300 W and a gas flow rate of 50 L / min using air as the working gas.

[0036] Preparation of smoke particles

[0037] In this embodiment, the fragrance generating agent is added in three steps, and the specific adding method is as follows:

[0038] S1: Place the pretreated modified activated carbon on a tray and dry it at 60°C for 15 minutes. Then, add it to the disc while it is still hot. While the disc is rotating, spray the atomizer and flavoring agent intermittently and alternately 3-5 times. In this embodiment, the atomizer is glycerin, and the flavoring agent is heated cigarette flavoring. The mass ratio of modified activated carbon to glycerin and heated cigarette flavoring is 3:0.5:0.5 to obtain premixed particles.

[0039] S2: Place 1 / 2 of the premixed particles in a disc and spray 1% of the mass of the premixed particles in the disc with a binder;

[0040] The adhesive of this embodiment was prepared as follows: chitosan was weighed into a beaker, hydroxymethyl methylcellulose was added at 5 times the mass of the chitosan, and glycerol was added at 12 times the mass of the hydroxymethyl methylcellulose, and the mixture was heated in a 60° C. water bath with stirring for 30 minutes and set aside.

[0041] S3: After stirring and mixing, add tobacco powder as an auxiliary material and stir and mix.

[0042] S4: Add fragrance generating agent into the disc and stir to mix.

[0043] S5: Add the remaining premixed particles in batches, repeat steps S3-S5, and add the total mass ratio of the auxiliary materials to the modified activated carbon to be 2:1, and the total mass ratio of the fragrance generating agent to the modified activated carbon to be 0.3:1. After rolling into particles, dry them at 90°C.

[0044] S6: Sieve the dried particles to select particles with a particle size of 20-30 mesh to obtain suction particles.

[0045] Example 2

[0046] Preparation of modified activated carbon

[0047] Silicon nitride nanosheets were added to deionized water at a solid-liquid ratio of 18 g / L and ultrasonically dispersed for 2 h to obtain a silicon nitride dispersion. Resorcinol and hexadecyltrimethylammonium bromide were weighed in a mass ratio of 1:3 and stirred and dissolved in a 45% volume fraction ethanol solution. The mass ratio of ethanol solution to hexadecyltrimethylammonium bromide was 55:1. A 25 wt% ammonia solution with the same mass of resorcinol was added dropwise and stirred for 25 min. Then, 1.5 wt% chitosan solution and silicon nitride dispersion were added. The mixture was stirred for 30 min, and formaldehyde solution with the same volume of ammonia solution was added dropwise. After the addition was completed, stirring was continued for 22 h. The mixture was freeze-dried to obtain a solid. The temperature was raised to 850 °C at a rate of 2 °C / min under a nitrogen atmosphere and kept warm for 3 h. After naturally cooling to room temperature, the solid was taken out and ground to obtain a modified activated carbon with a hierarchical porous structure. The average particle size of the modified activated carbon was 300 μm.

[0048] The prepared modified activated carbon is used to prepare smoke particles, specifically as follows:

[0049] Preprocessing

[0050] After the modified activated carbon was cleaned and dried, an adhesive was sprayed onto the surface of the modified activated carbon. The adhesive in this embodiment was obtained by stirring and mixing magnesium oxide and ethyl cellulose in a mass ratio of 2:8. The mass of the added adhesive was 2% of the mass of the modified activated carbon. The modified activated carbon was placed in kapok short fibers, and a kapok short fiber layer was wrapped on the surface of the modified activated carbon. Then, under an inert atmosphere, a semi-carbonization treatment was performed at a temperature of 350°C for 30 minutes. After the treatment was completed, the semi-carbonized kapok short fiber layer was placed in a low-temperature plasma reactor and subjected to low-temperature plasma treatment at a power of 300 W and a gas flow rate of 50 L / min using air as the working gas.

[0051] Preparation of smoke particles

[0052] S1: Place the pretreated modified activated carbon in a tray, dry it at 50°C for 20 minutes, and then add it to the disc while it is hot. While the disc is rotating, spray the atomizer and flavoring agent intermittently and alternately 3-5 times. In this embodiment, the atomizer is glycerin, and the flavoring agent is tobacco extract. The mass ratio of modified activated carbon to glycerin and tobacco extract is 3:0.5:0.5 to obtain premixed particles.

[0053] S2: Place 1 / 2 of the premixed particles in a disc and spray 3% of the mass of the premixed particles in the disc with a binder;

[0054] The adhesive of this embodiment was prepared as follows: chitosan was weighed into a beaker, hydroxymethyl methylcellulose was added at 5 times the mass of the chitosan, and glycerol was added at 12 times the mass of the hydroxymethyl methylcellulose, and the mixture was heated in a 60° C. water bath with stirring for 30 minutes and set aside.

[0055] S3: After stirring and mixing, add tobacco powder as an auxiliary material and stir and mix.

[0056] S4: Add fragrance generating agent into the disc and stir to mix.

[0057] S5: Add the remaining premixed particles in batches, repeat steps S3-S5, and add the total mass ratio of the auxiliary materials to the modified activated carbon to be 2:1, and the total mass ratio of the fragrance generating agent to the modified activated carbon to be 0.3:1. After rolling into particles, dry them at 90°C.

[0058] S6: Sieve the dried particles to select particles with a particle size of 20-30 mesh to obtain suction particles.

[0059] Example 3

[0060] Preparation of modified activated carbon

[0061] Silicon nitride nanosheets were added to deionized water at a solid-liquid ratio of 20 g / L and ultrasonically dispersed for 1 h to obtain a silicon nitride dispersion. Resorcinol and hexadecyltrimethylammonium bromide were weighed in a mass ratio of 1:3 and stirred and dissolved in a 50% volume fraction ethanol solution. The mass ratio of ethanol solution to hexadecyltrimethylammonium bromide was 45:1. A 25wt% ammonia solution equal to the mass of resorcinol was added dropwise and stirred for 30 min. Then, 2wt% chitosan solution and silicon nitride dispersion were added. The mass ratio of chitosan, silicon nitride nanosheets and hexadecyltrimethylammonium bromide is 2:0.1:1.2. The mixture is stirred and mixed for 30 minutes. A formaldehyde solution with an equal volume of ammonia solution is added dropwise. After the addition is completed, stirring is continued for 25 hours. The solid is freeze-dried to obtain a solid. Under a nitrogen atmosphere, the temperature is increased to 900°C at a rate of 1°C / min and kept warm for 2 hours. After naturally cooling to room temperature, it is taken out and ground to obtain a modified activated carbon with a hierarchical porous structure. The average particle size of the modified activated carbon is 225μm.

[0062] The prepared modified activated carbon is used to prepare smoke particles, specifically as follows:

[0063] Preprocessing

[0064] After cleaning and drying the modified activated carbon, an adhesive was sprayed onto the surface of the modified activated carbon. The adhesive in this embodiment was prepared by stirring potassium silicate and ethyl cellulose in a mass ratio of 2:8. The mass of the added adhesive was 2% of the mass of the modified activated carbon. The modified activated carbon was placed in kapok short fibers, and a kapok short fiber layer was wrapped on the surface of the modified activated carbon. Then, under an inert atmosphere, a semi-carbonization treatment was performed at a temperature of 340°C for 20 minutes. After the treatment was completed, the semi-carbonized kapok short fiber layer was placed in a low-temperature plasma reactor and subjected to low-temperature plasma treatment at a power of 300 W and a gas flow rate of 50 L / min using air as the working gas.

[0065] S1: Place the pretreated modified activated carbon on a tray and dry it at 40°C for 30 minutes. Then, add it to the disc while it is still hot. While the disc is rotating, spray the atomizer and flavoring agent intermittently and alternately 3-5 times. In this embodiment, the atomizer is glycerin, and the flavoring agent is heated cigarette flavor. The mass ratio of modified activated carbon to glycerin and tobacco flavor is 3:0.5:0.5 to obtain premixed particles.

[0066] S2: Place 1 / 2 of the premixed particles in a disc and spray 2% of the mass of the premixed particles in the disc with a binder;

[0067] The adhesive of this embodiment was prepared as follows: chitosan was weighed into a beaker, hydroxymethyl methylcellulose was added at 5 times the mass of the chitosan, and glycerol was added at 12 times the mass of the hydroxymethyl methylcellulose, and the mixture was heated in a 60° C. water bath with stirring for 30 minutes and set aside.

[0068] S3: After stirring and mixing, add tobacco powder as an auxiliary material and stir and mix.

[0069] S4: Add fragrance generating agent into the disc and stir to mix.

[0070] S5: Add the remaining premixed particles in batches, repeat steps S3-S5, and add the total mass ratio of the auxiliary materials to the modified activated carbon to be 2:1, and the total mass ratio of the fragrance generating agent to the modified activated carbon to be 0.3:1. After rolling into particles, dry them at 90°C.

[0071] S6: Sieve the dried particles to select particles with a particle size of 20-30 mesh to obtain suction particles.

[0072] The above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art will appreciate that the technical solutions of the present invention may be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, and such modifications or equivalents shall be encompassed by the claims of the present invention. Any techniques, shapes, and structures not described in detail herein are well known.

Claims

1. A heat-not-burn smoke-generating particle, characterized in that: The smoke-generating particles are formed by using modified activated carbon as a carrier, compounded with a flavoring agent, an atomizer, and auxiliary materials. The modified activated carbon is compounded by activated carbon particles and silicon nitride nanosheets. The modified activated carbon preparation method comprises the following steps: adding silicon nitride nanosheets to deionized water, ultrasonically dispersing for 1-2 hours to obtain a silicon nitride dispersion, weighing resorcinol and hexadecyltrimethylammonium bromide respectively, stirring and dissolving them in a 40-50% by volume ethanol solution, dropwise adding a 25wt% ammonia solution, stirring and mixing for 25-30 minutes, then adding a chitosan solution and the silicon nitride dispersion, stirring and mixing for 30 minutes, dropwise adding a formaldehyde solution, continuously stirring for 20-25 hours after the dropwise addition is completed, freeze-drying, heating the obtained solid to 850-900°C at a rate of 1-2°C / min under a nitrogen atmosphere, maintaining the temperature for 2-3 hours, naturally cooling to room temperature, and then taking out and grinding to obtain the modified activated carbon.

2. The heat-not-burn smoke-generating particles according to claim 1, characterized in that: The modified activated carbon has a hierarchical porous structure.

3. The heat-not-burn smoke-generating particles according to claim 2, characterized in that: The mass ratio of the modified activated carbon, the fragrance generating agent, the atomizer and the auxiliary materials is 3:(0.8-1):(0.5-1):(6-8).

4. The heat-not-burn smoke-generating particles according to claim 1, characterized in that: The particle size of the modified activated carbon is 120-350 μm.

5. The method for preparing heat-not-burn smoke-generating particles according to any one of claims 1 to 4, characterized in that: The preparation method of the smoke-generating particles specifically comprises the following steps: S1: Place the pretreated modified activated carbon on a tray and dry it at 40-60°C for 15-30 minutes. Then, add it to the disc while it is still hot. While the disc is rotating, spray the atomizer and fragrance agent intermittently and alternately 3-5 times to obtain premixed particles. S2: Place 1 / 2 of the premixed granules in a disc and spray with adhesive; S3: After stirring and mixing, add auxiliary materials and stir and mix; S4: Add the fragrance generating agent into the disc and stir to mix; S5: Add the remaining premixed particles in batches, repeat steps S3-S5, roll into particles, and dry; S6: Sieve the dried particles to select particles with a particle size of 20-30 mesh to obtain suction particles.

6. The method for preparing heat-not-burn smoke-generating particles according to claim 5, characterized in that: The pretreatment of the modified activated carbon is as follows: after cleaning and drying the modified activated carbon, an adhesive is sprayed on the surface of the modified activated carbon, the modified activated carbon is placed in kapok short fibers, a kapok short fiber layer is wrapped on the surface of the modified activated carbon, and then semi-carbonized in an inert atmosphere. After the treatment is completed, the semi-carbonized kapok short fiber layer is placed in a low-temperature plasma reactor and subjected to low-temperature plasma treatment using air as a working gas.

7. The method for preparing heat-not-burn smoke-generating particles according to claim 6, characterized in that: The adhesive is a composite adhesive, which includes component A and component B in a mass ratio of 1:(2-8), wherein the component A is a chitosan compound, and the component B is one or more of hydroxymethyl methylcellulose, hydroxypropyl methylcellulose, and hydroxyethyl methylcellulose.