A biomass-based charcoal material for reducing tar in tobacco, its preparation method and application

Abstract

This invention provides a biomass remnant char material for reducing tar in tobacco, its preparation method, and its application. The preparation method includes the following steps: mixing a biomass precursor with a chemical reagent solution, drying it, and then micro-expanding it, followed by activation, and then impregnating it with a metal ion solution to obtain the biomass remnant char material for reducing tar in tobacco. The preparation method provided by this invention utilizes the advantages of the multi-scale remnant structure of natural biomass, employing component degradation and microwave expansion to reshape its internal nano-microstructure. Through a physical activation process, well-developed hierarchical channels are constructed, achieving efficient anchoring of metal heteroatoms, enhancing the diffusion and adsorption behavior of tar particles in the remnant char material, and achieving a match between the transport and adsorption processes, thereby effectively improving the tar reduction performance of the product.

Description

Technical Field

[0001] This invention belongs to the field of tobacco materials technology, specifically relating to a tar-reducing biomass remnant char material for tobacco, its preparation method, and its application. Background Technology

[0002] Due to its widespread consumption, high consumption volume, and high tax revenue, the tobacco industry occupies a significant position in the national economy. Since 2014, the total annual tobacco production has reached over 2.8 million tons, with waste tobacco materials, including tobacco stems and leaves, accounting for 20%-30% of the raw materials annually. Furthermore, a large amount of tobacco straw remains underutilized, highlighting the crucial need for the tiered development of biomass resources. Moreover, the harmful effects of cigarette smoke have become one of the most serious public health problems globally, with over 500 million of the world's 1.1 billion smokers exposed to secondhand smoke. The main body of cigarette smoke contains various harmful components such as tar, CO, nicotine, polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines, hydrogen cyanide, and formaldehyde, posing serious health risks and potential carcinogenicity. Therefore, the tobacco industry faces the dual challenges of "resource quality improvement and value enhancement" and "cigarette harm reduction and tar reduction," which has become a crucial direction for the long-term sustainable development of the tobacco industry.

[0003] Currently, only 40% of tobacco stems, a typical waste product of tobacco, are developed and utilized as tobacco sheets, active extracts, and natural fuels. Approximately 60% remain as solid waste each year, primarily disposed of through methods such as destruction, landfill, and incineration, resulting in severe resource waste and air pollution. Therefore, current biomass utilization strategies mainly focus on preserving and derivation of its natural components and chemical species, lacking understanding and control over its original structure. This hinders the full utilization of the functionality of biomass structures and makes further quality improvement and value enhancement difficult. Tobacco biomass also possesses a multi-level plant structure formed through natural evolution, exhibiting an ordered remnant structure of cells-fiber bundles-fiber filaments-tripartite elements. It holds promise for introducing new components or structures while preserving its multi-scale structure to achieve reconstructive enhancement. Through component modulation and micro-gap reconstruction, micro-nano structures matching the diffusion and adsorption processes of tar particles can be constructed, enhancing the tar reduction performance of activated carbon materials for tobacco.

[0004] Currently, there are numerous invention patents for preparing activated carbon materials for cigarettes using tobacco waste or other types of biomass waste. Invention patent CN105146754B discloses a method for preparing activated carbon cigarette filter rods from tobacco straw. The tobacco straw is directly soaked in water and filtered, then activated using a physical activation method to produce straw activated carbon. Simultaneously, acetic acid straw fiber is prepared using a sulfite method and a dichloromethane homogeneous method. The two are combined to obtain an acetic acid straw fiber filter rod containing activated carbon. Invention patent CN106723353B discloses a method for preparing activated carbon for cigarettes using jute stalks as raw material. After dry distillation and carbonization, steam activation is performed to obtain activated carbon material for cigarettes with low ash content and high hardness. Invention patent CN107874318B discloses a method for preparing herbal charcoal granules. Herbal raw materials are carbonized to prepare granules, and then impregnated with a herbal compound extract to further improve the smoke adsorption capacity. However, the aforementioned invention patents all select specific biomass waste and adopt simple carbonization and physical activation treatment methods. They do not make full use of the natural residual structural advantages of biomass, nor do they adopt external field enhancement strategies to reshape and reconstruct the original nano-micro structure. As a result, the porous structure of the activated carbon material for tobacco cannot be directionally matched to the size range of tar particles in the flue gas, thus resulting in limited tar reduction capacity.

[0005] Therefore, in order to achieve high-value utilization of biomass waste and precise construction of tar-reducing functional materials for tobacco, it is urgent to develop new biomass remnant char materials for tobacco and improve the tar-reducing performance of porous char materials. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a biomass remnant char material for reducing tar in tobacco, its preparation method, and its applications. The preparation method provided by this invention utilizes the multi-scale remnant structure advantages of natural biomass, employing component degradation and microwave expansion to reshape its internal nano-microstructure. Through a physical activation process, well-developed hierarchical channels are constructed, achieving efficient anchoring of metal heteroatoms. This enhances the diffusion and adsorption behavior of tar particles in the remnant char material, matching the transport and adsorption processes, thereby effectively improving the tar reduction performance of the product.

[0007] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for preparing a tar-reducing biomass remnant char material for tobacco use, the method comprising the following steps: The biomass precursor is mixed with a chemical reagent solution, dried, and then microwave-expanded. After activation, it is mixed with a metal ion solution and impregnated to obtain the biomass remnant carbon material with tar-reducing function for tobacco.

[0008] The above method selectively removes hemicellulose and lignin components from biomass through chemical reagent treatment, thereby reshaping its nanoscale remnant structure while preserving the cellulose remnant structure. This facilitates the formation of interconnected hierarchical pore structures during activation, enhancing the diffusion behavior of tar particles in cigarette smoke within the filter material. Combined with microwave expansion treatment, the "steam explosion" effect generated by microwave heating expands the micropores left by component degradation, forming a more porous fibrous structure. This helps construct larger mesoporous channels during subsequent activation, matching and enhancing the size range of tar particles in cigarette smoke. Utilizing the oxygen defect interface properties exposed after biomass component degradation and microwave expansion treatment, metal ions are impregnated to achieve strong heteroatom anchoring and modulate the surface charge distribution of the remnant carbon material, improving the adsorption of particulate matter on the material surface. Each step is performed sequentially, resulting in a well-structured product that avoids structural collapse and improves tar reduction.

[0009] Preferably, the biomass precursor includes any one or a combination of at least two of the following: tobacco stalks, tobacco stems, tobacco ash, tobacco dust, pine wood, poplar wood, Scots pine wood, walnut wood, camphor wood, spruce wood, balsa wood, cypress wood, linden wood, beech wood, camphor wood, waste mushroom sticks, sugarcane bagasse, coconut shell, wheat straw, corn straw, rice straw, or potato straw.

[0010] Preferably, the chemical reagent includes any one or a combination of at least two of sodium hydroxide, potassium hydroxide, sodium chlorite, sodium hypochlorite, sodium sulfite, phosphoric acid, zinc chloride, hydrogen peroxide, or p-toluenesulfonic acid; Preferably, the concentration of the chemical reagent solution is 0.01-5 mol / L, such as 0.01 mol / L, 0.1 mol / L, 1 mol / L, 1.5 mol / L, 2 mol / L, 2.5 mol / L, 3 mol / L, 3.5 mol / L, 4 mol / L, 4.5 mol / L, or 5 mol / L, but not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0011] Preferably, the mixing treatment is carried out at a temperature of 100-160℃ for a time of 0.5-6 h. The temperature can be 100℃, 110℃, 120℃, 130℃, 140℃, 150℃ or 160℃, etc., and the time can be 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, 4.5 h, 5 h, 5.5 h or 6 h, etc., but is not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0012] Preferably, the frequency of the microwave expansion is 1500-3000 MHz, and the time is 10-60 min. The frequency can be 1500 MHz, 1600 MHz, 1700 MHz, 1800 MHz, 1900 MHz, 2000 MHz, 2100 MHz, 2200 MHz, 2300 MHz, 2400 MHz, 2500 MHz, 2600 MHz, 2700 MHz, 2800 MHz, 2900 MHz, or 3000 MHz, etc., and the time can be 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, or 60 min, etc., but is not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0013] Preferably, the activation specifically involves heating and holding the material in an activation medium atmosphere.

[0014] Preferably, the activation medium atmosphere includes any one or a combination of at least two of nitrogen, carbon dioxide, or water vapor.

[0015] Preferably, the heating rate is 1-20℃ / min, and the temperature is increased to 600-1000℃. The heating rate can be 1℃ / min, 2℃ / min, 4℃ / min, 6℃ / min, 8℃ / min, 10℃ / min, 12℃ / min, 14℃ / min, 16℃ / min, 18℃ / min, or 20℃ / min, etc., but is not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0016] Preferably, the heat preservation time is 1-10 h, such as 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h or 10 h, but not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0017] Preferably, the metal ions include any one or a combination of at least two of lithium ions, sodium ions, magnesium ions, calcium ions, iron ions, nickel ions, copper ions, or zinc ions.

[0018] Preferably, the concentration of the metal ion solution is 0.05-5 mol / L, such as 0.05 mol / L, 0.1 mol / L, 0.5 mol / L, 1 mol / L, 1.5 mol / L, 2 mol / L, 2.5 mol / L, 3 mol / L, 3.5 mol / L, 4 mol / L, 4.5 mol / L, or 5 mol / L, but not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0019] Preferably, the impregnation amount of the metal ions is 0.01-10 wt%, such as 0.01 wt%, 0.1 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, or 10 wt%, but is not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0020] The above parameter control and reagent selection can further improve the coking effect of the product.

[0021] Secondly, the present invention provides a tar-reducing biomass remnant char material for tobacco prepared by the preparation method described above.

[0022] Thirdly, the present invention provides the application of the biomass remnant char material with tar-reducing function for tobacco as described above in the preparation of cigarette filter materials.

[0023] Fourthly, the present invention also provides a cigarette, wherein the cigarette filter comprises the tar-reducing biomass remnant char material for tobacco as described above.

[0024] Preferably, the loading of the tar-reducing biomass remnant char material in the cigarette is 1-50 mg / cigarette, such as 1 mg / cigarette, 5 mg / cigarette, 10 mg / cigarette, 15 mg / cigarette, 20 mg / cigarette, 25 mg / cigarette, 30 mg / cigarette, 35 mg / cigarette, 40 mg / cigarette, 45 mg / cigarette, or 50 mg / cigarette, but is not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0025] Compared with the prior art, the present invention has the following beneficial effects: (1) The process described in this invention makes full use of the advantages of the multi-scale residual structure of natural biomass, adopts component degradation and microwave expansion to reshape its internal nano-micro fine structure, constructs well-developed multi-level channels through physical activation process, and achieves efficient anchoring of metal heteroatoms, strengthens the diffusion and adsorption behavior of tar particles in residual carbon materials, and achieves matching of the transfer and adsorption processes, thereby effectively improving the tar reduction performance of cigarette filter materials.

[0026] (2) The process described in this invention is compatible with a variety of natural biomass precursors. The process is simple and easy to control. The structure and properties of the prepared tobacco tar-reducing biomass remnant char material are highly adjustable, making it suitable for large-scale scale-up and industrial production. Attached Figure Description

[0027] Figure 1 This is the SEM morphology characterization of the product in Experiment Example 1; Figure 2 This shows the pore size distribution trend of the product in Experiment Example 1. Detailed Implementation

[0028] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0029] Example 1: (1) Weigh 15 g of tobacco stalk particles with a particle size of 30 mesh, then add them to 200 mL of 0.5 mol / L p-toluenesulfonic acid solution, and place them at 130℃ and stir at 800 rpm for 1 hour to degrade lignin and hemicellulose components. Then wash them thoroughly with deionized water until the pH value is neutral, and dehydrate them by blowing air to obtain biomass precursor particles with a moisture content of 20%.

[0030] (2) Then, it is placed in a microwave expansion device and microwave expanded at a high frequency of 2000 MHz for 30 minutes to obtain expanded particulate material.

[0031] (3) Further activate it by heating it to 800°C at a rate of 5°C / min under a carbon dioxide atmosphere and holding it at that temperature for 1.5 hours to finally obtain biomass remnant carbon material.

[0032] (4) Copper sulfate was selected as the metal precursor to prepare copper ion-impregnated biomass remnant char material with an impregnation amount of 5 wt%. 10 g of biomass remnant char was added to 100 mL of 2 mol / L copper sulfate solution and stirred at 800 rpm for 12 h. The resulting material was then filtered and dried to obtain biomass remnant char material for reducing tar in tobacco. The SEM morphology was characterized as follows: Figure 1 As shown, its surface exhibits a porous and loose morphology, accompanied by the distribution of metal particles of approximately 8 nm. The total pore volume, measured by nitrogen adsorption-desorption characterization, is 2.33 cm³. 3 / g, Figure 2 The pore size distribution results show that its pores are widely distributed between 2-20 nm, with a mesoporosity of 83% and an average pore size of 12 nm.

[0033] Comparative Example 1 The other conditions are the same as in Experiment 1, except that the stirring temperature is 180℃ after adding p-toluenesulfonic acid solution.

[0034] Comparative Example 2 The other conditions are the same as in Experiment 1, except that the frequency of microwave expansion is 3500 MHz, which is different from Experiment 1.

[0035] Comparative Example 3 The other conditions are the same as in Experiment 1, except that the duration of microwave expansion is 90 min, which is different from Experiment 1.

[0036] Comparative Example 4 The other conditions are the same as in Experiment 1, except that "activation is carried out by heating to 500°C in a carbon dioxide atmosphere" is different from Experiment 1.

[0037] Comparative Example 5 The other conditions are the same as in Experiment 1, except that the metal ion is tin ion, which is different from Experiment 1.

[0038] Comparative Example 6 The other conditions are the same as in Experiment 1, except that the "impregnation amount of metal ions is 12 wt%" is different from that in Experiment 1.

[0039] Based on Experiment 1, Comparative Examples 1-6 were compared and analyzed in terms of the preparation of biomass charcoal materials, metal impregnation treatment, material structure information, and cigarette tar reduction performance, as detailed in Table 1. The sensory quality of the cigarettes was assessed by seven smoking experts using a standardized scoring method, evaluating the cigarettes' luster, aroma, harmony, off-flavors, irritation, and aftertaste. The average scores were then taken, and the corresponding sensory quality evaluations are shown in Table 3.

[0040] When the preparation conditions of the biomass charcoal material are not within the range described in this invention, i.e., Comparative Examples 1-4, the resulting tobacco material does not possess the characteristic of "total pore volume ≥ 1.0 cm³". 3 The structural characteristics of " / g, mesoporous rate of 30-99%, average pore size ≥10 nm" result in poor tar reduction effect in cigarettes. When the metal impregnation conditions of the biomass remnant char material are not within the range described in this invention, i.e., Comparative Examples 5-6, the prepared tobacco material still cannot achieve good tar reduction performance, and the improvement in the irritation and aftertaste of the smoke is not significant. In contrast, Experimental Example 1 has a well-developed mesoporous structure and suitable surface metal ion modification, achieving a tar reduction of up to 38.6%, and significantly improving the richness and aroma quality of cigarette smoke, while reducing irritation and aftertaste.

[0041] Experiment Example 2 The other conditions are the same as in Experiment 1, except that "the chemical reagent used for component degradation is sodium chlorite with a concentration of 1.5 mol / L and the treatment temperature is 150℃", which is different from Experiment 1.

[0042] Experimental Example 3 Other conditions are the same as in Experiment 1, except that "the chemical reagent for component degradation is phosphoric acid with a concentration of 1 mol / L, the treatment temperature is 120℃, the activation medium is nitrogen atmosphere with an activation temperature of 900℃, the holding time is 2 h, and the impregnating metal is nickel ions" are different from those in Experiment 1.

[0043] Experiment Example 4 The other conditions are the same as in Experiment 1, except that "the biomass precursor is tobacco stem, the treatment time for component degradation is 2 h, the microwave frequency is 3000 MHz, the activation medium is nitrogen atmosphere, the activation temperature is 900℃, the impregnating metal is nickel ions, and the metal impregnation amount is 3 wt%" are different from those in Experiment 1.

[0044] Experimental Example 5 The other conditions are the same as in Experiment 1, except that "the biomass precursor is spruce, the chemical reagent for component degradation is sodium hydroxide, the treatment temperature is 110℃, the microwave frequency is 2500 MHz, the microwave duration is 45 min, the heat preservation time is 1 h, and the impregnating metal is iron ions" are different from those in Experiment 1.

[0045] Experimental Example 6 The other conditions are the same as in Experiment 1, except that "the biomass precursor is poplar wood, the chemical reagent for component degradation is sodium chlorite, the treatment temperature is 150℃, the treatment time is 0.5 h, the microwave frequency is 2500 MHz, the activation medium is water vapor atmosphere, the heat preservation time is 1 h, the impregnating metal is magnesium ions, and the metal impregnation amount is 3 wt%" are different from those in Experiment 1.

[0046] Experimental Example 7 The other conditions are the same as in Experiment 1, except that "the biomass precursor is coconut shell, the concentration of the chemical reagent for component degradation is 1 mol / L, the treatment time is 3 h, the microwave duration is 60 min, the activation medium is nitrogen atmosphere, the activation temperature is 700℃, the holding time is 2 h, the impregnating metal is lithium ions, and the metal impregnation amount is 10 wt%" are different from those in Experiment 1.

[0047] Comparative Example 1 Other conditions are the same as in Experiment Example 1, except that "step (4) is not included".

[0048] Comparative Example 2 Other conditions are the same as in Experiment 1, except that "steps (1) and (2) are reversed, that is, the tobacco rod particles are first expanded by microwave, and then treated with p-toluenesulfonic acid solution".

[0049] The above products were manufactured into cigarettes. The cigarette filter adopted a "10+6+14" structure from the tobacco end to the near-lip end. The "10" and "14" segments were cellulose acetate rods (10 mm and 14 mm long, respectively), while the tar-reducing biomass remnant charcoal material was added to the 6 mm long filter cavity. The composition and length of the tobacco segments were consistent in all cigarette samples (Xuanhemen tobacco, 66 mm long). Cigarettes without tar-reducing filter rods were used as control samples. Before the test, all cigarettes were equilibrated for 48 h at a temperature of (22±1)℃ and a relative humidity of (60±2)%. Then, they were sorted by weight (average weight ±0.02 g) and draw resistance (average draw resistance ±49 Pa) to select test cigarettes that met the standards. Cigarette smoking tests were conducted on a smoking machine under standard smoking conditions, and the tar release in the cigarette smoke was tested according to standard GB / T19609-2004.

[0050] Based on Experiment 1, Experiments 2-7 optimized the degradation conditions, microwave expansion conditions, activation conditions, and impregnation conditions of biomass components, respectively; Comparative Examples 1-2 studied whether or not metal ions were impregnated and the operation steps, respectively; and compared and analyzed their cigarette tar reduction performance, as shown in Table 2.

[0051] Table 1 Table 2 Table 3 The data above shows that by using specific parameter control and reagent selection, and controlling the operation steps, this invention can effectively form a specific pore structure and combine with metal ions to achieve excellent coke reduction effect.

[0052] The biomass precursor processing strategy provided by this invention utilizes the natural multi-level fine remnant structure to reshape the nano- and micro-structure through component degradation, microwave expansion, and physical activation. Further surface modification is achieved through metal ion impregnation, resulting in biomass remnant char material with tar-reducing properties for cigarettes. Based on the comparison of Experimental Examples 1-7, this processing strategy possesses a certain degree of universality for biomass precursors. The developed and prepared biomass remnant char material with tar-reducing properties for cigarettes exhibits excellent tar-reducing performance within the condition range described in this invention, and can significantly increase the harmony of cigarette smoke, improve aroma quality and smoothness, and reduce irritation and aftertaste.

[0053] The applicant declares that this invention illustrates the tar-reducing biomass remnant charcoal material for tobacco use, its preparation method, and its application through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection and disclosure scope of this invention.

[0054] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0055] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

Claims

1. A method for preparing a biomass-derived charcoal material with tar-reducing function for tobacco, characterized in that, The preparation method includes the following steps: The biomass precursor is mixed with a chemical reagent solution, dried, and then microwave-expanded. After activation, it is mixed with a metal ion solution and impregnated to obtain the biomass remnant carbon material with tar-reducing function for tobacco.

2. The method for preparing the tobacco tar-reducing biomass remnant char material according to claim 1, characterized in that, The biomass precursors include any one or a combination of at least two of the following: tobacco stalks, tobacco stems, tobacco ash, tobacco dust, pine wood, poplar wood, Scots pine wood, walnut wood, camphor wood, spruce wood, balsa wood, cypress wood, linden wood, beech wood, camphor wood, waste mushroom sticks, sugarcane bagasse, coconut shells, wheat straw, corn straw, rice straw, or potato straw.

3. The method for preparing the tobacco tar-reducing biomass remnant char material according to claim 1 or 2, characterized in that, The chemical reagents include any one or a combination of at least two of the following: sodium hydroxide, potassium hydroxide, sodium chlorite, sodium hypochlorite, sodium sulfite, phosphoric acid, zinc chloride, hydrogen peroxide, or p-toluenesulfonic acid. Preferably, the concentration of the chemical reagent solution is 0.01-5 mol / L; Preferably, the mixing treatment is performed at a temperature of 100-160°C for 0.5-6 hours.

4. The method for preparing the tobacco tar-reducing biomass remnant char material according to any one of claims 1-3, characterized in that, The microwave expansion frequency is 1500-3000 MHz, and the duration is 10-60 min.

5. The method for preparing the tobacco tar-reducing biomass remnant char material according to any one of claims 1-4, characterized in that, The activation specifically involves heating and holding the material in an activation medium atmosphere.

6. The method for preparing the tobacco tar-reducing biomass remnant char material according to claim 5, characterized in that, The activation medium atmosphere includes any one or a combination of at least two of nitrogen, carbon dioxide, or water vapor; Preferably, the heating rate is 1-20℃ / min, and the temperature is increased to 600-1000℃; Preferably, the heat preservation time is 1-10 h.

7. The method for preparing the tobacco tar-reducing biomass remnant char material according to any one of claims 1-6, characterized in that, The metal ions include any one or a combination of at least two of the following: lithium ions, sodium ions, magnesium ions, calcium ions, iron ions, nickel ions, copper ions, or zinc ions. Preferably, the concentration of the metal ion solution is 0.05-5 mol / L; Preferably, the impregnation amount of the metal ions is 0.01-10 wt%.

8. A biomass remnant char material for tobacco with tar reduction function prepared by the preparation method according to any one of claims 1-7.

9. The application of the tar-reducing biomass remnant char material according to claim 8 in the preparation of cigarette filter materials.

10. A cigarette, characterized in that, The cigarette filter includes the tar-reducing biomass remnant char material for tobacco as described in claim 8; Preferably, the loading of the tar-reducing biomass remnant char material in the cigarette is 1-50 mg / cigarette.

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