Manufacturing method of activated carbon fiber for adsorption of harmful gases and filter containing activated carbon fiber manufactured by this manufacturing method

Abstract

The present invention relates to a method for manufacturing activated carbon fibers for adsorbing harmful gases and a filter comprising activated carbon fibers manufactured by the method. The invention provides a method for manufacturing activated carbon fibers for adsorbing harmful gases using isotropic pitch, which has excellent mechanical strength and can lower manufacturing costs compared to polyacrylonitrile (PAN)-based and cellulose-based activated carbon fibers. In addition, the filter includes activated carbon fibers having a large specific surface area, which can exhibit more than 10 times the adsorption and removal performance compared to conventional woody granular activated carbon, more than 100 times the adsorption rate, and provides a filter with excellent selective removal effect for specific chemical species.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing activated carbon fibers for adsorbing harmful gases and a filter comprising activated carbon fibers manufactured by the method. Background Technology

[0002] Generally, various odors originate from sources such as kimchi, fish, cigarette smoke, excrement, and garbage when using household items like refrigerators, air conditioners, diapers, sanitary pads, cigarettes, shoe cabinets, and wardrobes, or in everyday living spaces like bedrooms, bathrooms, and car interiors. Representative examples of odor-causing substances include major odor sources such as ammonia, trimethylamine, acetaldehyde, and methyl mercaptan (methanthiol), as well as methyl sulfide, dimethyl disulfide, hydrogen sulfide, nitric oxide, nitrous oxide, and styrene. Filters utilizing deodorizing powders such as activated carbon, zeolite, and titanium dioxide photocatalysts are used in automobiles and interiors to remove or reduce these odors.

[0003] Furthermore, clean air is an indispensable and important issue not only for human health but also for industrial development. Due to technological innovation in industrial sites, highly clean spaces are required across a wide range of fields. In addition, in building HVAC systems that provide clean and comfortable spaces for workers, high-performance air filters that effectively remove cigarette smoke and other pollutants are required in addition to the HVAC system to satisfy building management laws.

[0004] It goes without saying that filters must possess not only the aforementioned deodorizing characteristics but also excellent filtration characteristics for collecting and filtering fine dust. Gas filters are designed to filter out impurity particles contained in gases, and their applications are very broad. For example, gas filters for automobile engines or air conditioning systems are employed to improve engine efficiency or cleaning efficiency by filtering out dust and other particles mixed in the air. Furthermore, in response to industrial development and the rising awareness of hygiene, the applications and market for gas filters are increasing significantly, including filter bags, automobile cabin filters, power plant gas turbine filters, semiconductor air filters, filters for household air purifiers, and vacuum cleaners. Examples include automobile cabin air filters and filters for air conditioning or air purification.

[0005] Meanwhile, as a method for applying deodorizing powders such as activated carbon and zeolite to cabin air filters, HVAC filters, or air purification filters, a method is used in which the deodorizing powders are attached to a non-woven fabric with filtration capabilities using a binder (for example, dispersed together with hot-melt powder and then heat-bonded).

[0006] However, the binder inevitably reduces the effective amount of activated carbon and clogs the pores of the deodorizing powders, thereby decreasing the overall air permeability of the filter material and causing problems that degrade deodorizing performance. Despite these issues, the reason a binder must be used is to prevent the deodorizing powders from detaching from the nonwoven fabric.

[0007] Therefore, there is a need to develop technology capable of manufacturing filters that can increase removal efficiency by adsorbing harmful gases without using binders. Prior art literature

[0008] (Patent Document 0001) KR 10-1647966 B1 The problem to be solved

[0009] The object of the present invention is to provide a method for manufacturing activated carbon fibers for adsorbing harmful gases and a filter comprising activated carbon fibers manufactured by the method.

[0010] Another objective of the present invention is to provide a method for manufacturing activated carbon fibers for adsorbing harmful gases using isotropic pitch, which has excellent mechanical strength and can lower manufacturing costs compared to polyacrylonitrile (PAN)-based and cellulose-based activated carbon fibers.

[0011] Another objective of the present invention is to provide a filter comprising activated carbon fibers having a large specific surface area, which can exhibit more than 10 times the adsorption and removal performance compared to conventional woody granular activated carbon, more than 100 times the adsorption speed, and excellent selective removal effect for specific chemical species. means of solving the problem

[0012] To achieve the above objective, the present invention relates to a method for manufacturing activated carbon fibers for adsorbing harmful gases, comprising the steps of: manufacturing isotropic pitch fibers by melt-spinning isotropic pitch at 250°C to 260°C using a nozzle of 0.75 mm; stabilizing the isotropic pitch fibers; carbonizing the stabilized isotropic pitch fibers; and activating the carbonized isotropic pitch fibers to manufacture activated carbon fibers, wherein the activated carbon fibers have an excellent removal effect due to the adsorption of harmful gases and can exhibit a fast adsorption rate.

[0013] The above activated carbon fiber has excellent adsorption performance for harmful gases consisting of SOx, NOx, and mixtures thereof.

[0014] The above stabilization step may involve increasing the temperature to a temperature condition of 280°C to 300°C at a rate of 0.5°C / min to 1°C / min and stabilizing for 0.5 to 1.5 hours.

[0015] The above carbonization step may involve increasing the temperature to 700°C to 800°C at a rate of 5°C / min to 15°C / min and carbonizing for 0.5 hours to 1.5 hours.

[0016] The above activation step may involve increasing the temperature to 800°C to 900°C at a rate of 5°C / min to 15°C / min under an inert gas atmosphere, supplying steam, and activating for 0.5 hours to 1.5 hours.

[0017] Activated carbon fibers for adsorbing harmful gases according to another embodiment of the present invention can be manufactured by the above manufacturing method.

[0018] A filter according to another embodiment of the present invention may include the activated carbon fiber. Effects of the invention

[0019] The present invention relates to a method for manufacturing activated carbon fibers for adsorbing harmful gases using isotropic pitch, which has excellent mechanical strength and can lower manufacturing costs compared to polyacrylonitrile (PAN)-based and cellulose-based activated carbon fibers.

[0020] In addition, a filter containing activated carbon fibers having a large specific surface area can exhibit more than 10 times the adsorption and removal performance compared to conventional woody granular activated carbon, more than 100 times the adsorption rate, and can provide a filter with excellent selective removal effect for specific chemical species. Brief explanation of the drawing

[0021] FIG. 1 relates to a nitrogen adsorption isotherm of an activated carbon fiber according to one embodiment of the present invention. FIG. 2 relates to a nitrogen adsorption isotherm of an activated carbon fiber according to one embodiment of the present invention. Specific details for implementing the invention

[0022] Hereinafter, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0023] The carbon materials industry has developed around the automotive and shipbuilding industries and is a field capable of high-performance, high-value-added production, green energy, and the convergence of technologies, making it one of the foundational industries that creates a large number of jobs and stable growth engines.

[0024] Due to the issue of fine dust, which is classified as a Class 1 carcinogen, the demand for activated carbon used in final products to reduce or defend against it is steadily growing. In particular, most of the environmental industry uses it as a filtration and separation device, and it is widely applied in the water and sewage, chemical, electrical and electronic, food and beverage, genetic engineering, pharmaceutical, mining, and paper industries.

[0025] Among them, the most widely used filter material is fiber material; in particular, filters using activated carbon fiber are essential core components for gaseous or liquid filters because the carbon fibers are carbonized and activated to form micropores on the fiber surface, resulting in excellent separation effects through adsorption.

[0026] At sites where high-temperature exhaust gases are emitted, high-speed ventilation and dust collection equipment are in operation; however, if toxic gases are not effectively removed, it not only creates a fatal environment for workers but also results in the toxic gases being inevitably released to the outside.

[0027] Currently, granular activated carbon is used, but since the amount of adsorption removal is low, the replacement cycle is extremely short (1 month), and the removal efficiency drops rapidly, showing an average removal efficiency of only 50% of the total harmful gases generated on-site, which causes health problems for workers and about 50% of harmful substances are released into the air.

[0028] However, the current situation is that the domestic industry relies entirely on imports due to the difficulty of manufacturing activated carbon fiber itself and reasons such as advanced countries like Japan avoiding technology transfer regarding raw materials.

[0029] Therefore, as global interest in the environmental industry increases and demand is predicted to rise in more countries, there is a need to develop technology that can replace expensive activated carbon fibers, which are currently entirely dependent on imports. The present invention manufactures fibers from isotropic pitch using a high-temperature melt spinning method, and then produces activated carbon fibers by subjecting the carbon fibers produced by melt spinning to stabilization, pre-carbonization, and activation steps, thereby possessing excellent pore characteristics and capable of replacing existing expensive granular activated carbon that is entirely dependent on imports.

[0030] A general method for manufacturing carbon fibers involves obtaining organic fibers, which are carbon fiber precursors, by thermally melting carbon fiber starting materials such as polyacrylonitrile, petroleum or coal-based pitch (isotropic or anisotropic), and phenol resin to perform melt spinning or melt blown spinning, or by dissolving them in a solvent to perform solution spinning. In particular, isotropic carbon fibers produced from petroleum or coal-based pitch are used as various electrode materials, fillers for composite materials, and thermal insulation materials, and have advantages such as low cost, high productivity, and a simple manufacturing method.

[0031] Pitch-based carbon fibers are classified into mesophase and isotropic types depending on the optical state of the pitch. It is known that using pitch containing anisotropy is essential for manufacturing high-performance carbon fibers in the pitch-based category. It is known that pitch without anisotropy—that is, optically isotropic pitch—cannot yield high-performance carbon fibers and can only produce, for instance, general-purpose grades.

[0032] In addition, pitch-based carbon fibers are obtained through melt spinning or melt spray spinning, and in the case of anisotropic pitch, the melt spinning method can be used. In the case of isotropic pitch, it is usually spun by the melt spray spinning method, and melt spray spinning produces short fiber mats with short fiber lengths rather than continuous fibers such as PAN carbon fibers or anisotropic (mesophase) carbon fibers, and the produced pitch fiber mats are manufactured into carbon fiber nonwoven fabrics by undergoing stabilization (or infusibility) and carbonization processes.

[0033] The above isotropic carbon fiber has a lower elastic modulus compared to anisotropic fibers, so the entanglement between short fibers is relatively good, but the tensile strength of the short fibers is low. It is weak against bending or twisting, and since the number of twists is less than that of cotton yarn, the tensile strength is not high. Therefore, it is known that it is difficult to manufacture continuous yarn from isotropic carbon fibers.

[0034] In the case of the above-mentioned anisotropic pitch, it forms a stacked structure in which condensed polycyclic aromatic planar molecules are arranged in parallel. During the melt spinning process, the stacked structure tends to align parallel to the fiber axis, but because it is generally processed at high temperatures for a long time, problems such as thermal deterioration, including an increase in quinoline insoluble matter and the generation of decomposition gases, occur during the melt spinning process. In particular, in the case of pitch composed of 100% anisotropy, the above problems are significant because the processing time at high temperatures is long and the softening point is also high.

[0035] Furthermore, in the case of pitch in which anisotropy and isotropy are mixed, uniform melt spinning becomes difficult, such as when fiber breakage occurs, due to the non-uniform mixture of regularly arranged and irregular constituent molecules.

[0036] To prevent such problems, the present invention relates to a method for manufacturing activated carbon fibers based on isotropic pitch raw materials by a melt spinning method. By using petroleum-based isotropic pitch raw materials, activated carbon fibers can be manufactured and excellent pore characteristics can be secured. Consequently, excellent adsorption effects for harmful gases can be exhibited, resulting in excellent performance in removing harmful gases.

[0037] Specifically, a method for manufacturing an activated carbon fiber for adsorbing harmful gases according to one embodiment of the present invention may include the steps of: manufacturing an isotropic pitch fiber by melt-spinning an isotropic pitch at 250°C to 260°C with a nozzle of 0.75 mm; stabilizing the isotropic pitch fiber; carbonizing the stabilized isotropic pitch fiber; and activating the carbonized isotropic pitch fiber to manufacture an activated carbon fiber.

[0038] The activated carbon fiber produced by the above manufacturing method exhibits an excellent removal effect due to the adsorption of harmful gases and can demonstrate a rapid adsorption rate. The harmful gases are harmful gases consisting of SOx, NOx, and mixtures thereof, and are characterized by excellent adsorption performance for said harmful gases.

[0039] The step of manufacturing the isotropic pitch fibers described above is a step of manufacturing isotropic pitch fibers by melt-spinning the isotropic pitch at 250°C to 260°C with a nozzle of 0.75 mm, wherein the isotropic pitch is a petroleum-based isotropic pitch and may be manufactured by heat-treating one or more carbon raw materials selected from the group consisting of pyrolyzed fuel oil (PFO), naphtha cracking bottom oil (NCB), ethylene bottom oil (EBO), heavy oil, extra-heavy oil, vacuum residue (VR), atmospheric residue, FCC-DO (fluid catalytic cracking decant oil), de-asphalted oil (DAO), and coal tar.

[0040] The above isotropic pitch may have a softening point of 200°C to 300°C and a quinoline insoluble content of 3% by weight or less. The above isotropic pitch may have a softening point of 200°C to 250°C and a quinoline insoluble content of 3% by weight or less, or a softening point of 220°C and a quinoline insoluble content of 3% by weight or less. When using an isotropic pitch having a softening point and quinoline insoluble content within the above ranges, the formation of insoluble solids and mesophase within the pitch is suppressed to the maximum extent, resulting in excellent spinnability, high elongation, and significantly increased tensile strength.

[0041] The above petroleum-based isotropic pitch can be manufactured into isotropic pitch fibers by melt spinning.

[0042] The above spinning may mean forming a petroleum-based pitch precursor into a powder, melting it, and then extruding it from a spinning nozzle to form a fibrous structure.

[0043] In order to manufacture the activated carbon fiber based on the above isotropic pitch raw material, an economical process can be achieved by preventing single filaments to obtain physical properties above a certain level during spinning and by performing the process under conditions of high spinnability to increase the yield.

[0044] The above spinning is performed at a temperature 30 to 40°C higher than the softening point of the isotropic pitch, and when melt spinning, the temperature conditions proceed at 250°C to 260°C, so that long fibers can be spun.

[0045] In addition, the diameter of the nozzle for the melt spinning may be 0.75 mm. The fibers spun within the above range for the nozzle diameter for the melt spinning may have a diameter of 15 µm to 20 µm.

[0046] Following the melt spinning step described above, the next step is to stabilize the manufactured isotropic pitch fiber. This stabilization refers to thermally stabilizing (non-fusible) the manufactured fiber so that it does not dissolve in a solvent and does not melt at subsequent temperatures.

[0047] The above stabilization step may involve increasing the temperature at a rate of 0.5℃ / min to 1℃ / min to a temperature condition of 280℃ to 300℃ and stabilizing for 1 to 3 hours. The above stabilization step may involve stabilizing isotropic pitch fibers produced at 250℃ to 260℃ during melt spinning, and may involve increasing the temperature to the above temperature range to reach a temperature condition for stabilization.

[0048] More specifically, the stabilization step involves loading isotropic pitch fibers into a high-temperature furnace under an oxygen atmosphere, heating them to 280°C to 300°C at a heating rate of 0.5°C / min to 1°C / min, and stabilizing them for 1 to 3 hours. Since thermal melting may occur during the stabilization reaction due to a self-oxidizing exothermic reaction during the rapid oxidation reaction, causing fiber fusion, it is desirable to heat treat at a temperature 20 to 30°C lower than the maximum exothermic temperature to effectively remove impurities and improve productivity. Therefore, the stabilization step may be carried out under the above-mentioned conditions, but it is not limited to the above conditions, and any conditions capable of suppressing fiber fusion and effectively removing impurities and improving productivity may be used without limitation.

[0049] After the above stabilization step, the stabilized isotropic pitch fiber is carbonized, and carbonization may mean increasing the carbon orientation of the stabilized fiber and releasing impure gases on the fiber to produce a more stable fiber.

[0050] The above carbonization may be performed by carbonizing isotropic pitch fibers stabilized at 280°C to 300°C under the heating conditions described below, by heating them to the carbonization temperature condition.

[0051] The carbonization step may involve increasing the temperature to 700°C to 800°C at a rate of 5°C / min to 15°C / min and carbonizing for 0.5 to 1.5 hours. Specifically, the material may be introduced into a high-temperature furnace in an inert gas atmosphere, increased the temperature to 700°C or 800°C at a rate of 10°C / min, and maintained for 1 hour to carbonize. By carbonizing under these conditions, the carbon orientation of the stabilized fiber can be increased, and impure gases can be discharged to produce a more stable fiber. The isotropic pitch fiber has a randomly distributed molecular structure and has low strength, making it prone to breaking easily; however, through the preliminary carbonization step, the carbon orientation can be increased, and a stable fiber can be produced.

[0052] The above inert gas may be selected from the group consisting of nitrogen, argon, helium, krypton, neon, and mixtures thereof, and the carbonization step may be carried out under a nitrogen or / and argon gas atmosphere.

[0053] The above S400 step may be a step of manufacturing activated carbon fibers by activating the carbonized isotropic pitch fibers using steam. The activation step may mean forming micropores on the fiber surface to enhance adsorption performance by inducing an activation reaction of the carbon fibers.

[0054] The above activation step may involve activating isotropic pitch fibers carbonized at 700°C to 800°C by raising the temperature to the temperature of the activation step under the heating conditions described later.

[0055] Specifically, the activation step may involve increasing the temperature to 800°C to 900°C at a rate of 5°C / min to 15°C / min under an inert gas atmosphere, supplying steam, and activating for 0.5 to 1.5 hours. More specifically, the activated carbon fiber may be manufactured by introducing it into a tube furnace under an inert gas atmosphere, increasing the temperature to 800°C or 900°C at a rate of 10°C / min, and then maintaining it for 30 minutes to 1 hour within a steam flow rate range of 0.4 to 1.2 g / min to induce an activation reaction. Under the conditions of the activation step, the activated carbon fiber can be induced to form micropores on the surface of the fiber, thereby increasing its adsorption performance.

[0056] The activated carbon fiber produced by the above manufacturing method is environmentally friendly in that it uses petroleum-based isotropic pitch, and can be provided as a method for manufacturing activated carbon fiber with reduced production costs that can replace conventional expensive activated carbon fibers.

[0057] An activated carbon fiber for adsorbing harmful gases according to another embodiment of the present invention can be manufactured by the above manufacturing method and has a specific surface area of ​​1000 m² 2 It can be more than / g.

[0058] The above activated carbon fiber may have a diameter of 15㎛ to 20㎛. The activated carbon fiber using the isotropic pitch of the present invention can be utilized more widely in fields requiring strength by securing excellent mechanical strength along with a reduction in cost compared to polyacrylonitrile (PAN)-based and cellulose-based activated carbon fibers.

[0059] In addition, the isotropic pitch-based activated carbon fiber of the present invention has a high specific surface area and adsorption capacity, and compared to conventional low-cost woody granular activated carbon, it has more than 10 times the adsorption removal performance, more than 100 times the adsorption speed, and can selectively remove specific chemical species.

[0060] Preparation Example 1

[0061] Preparation of activated carbon fibers using isotropic pitch

[0062] Isotropic pitch fibers were manufactured by melt spinning using isotropic pitch with a softening point of 220°C. The isotropic pitch was melt-spun using a nozzle with a hole of 0.75 mm, and the spinning conditions were 250°C to 260°C in an N2 gas atmosphere.

[0063] The manufactured isotropic pitch fiber was heated to 260°C to 300°C at a heating rate of 0.5°C / min or 1°C / min and stabilized by maintaining it in an air atmosphere for 1 hour.

[0064] The above stabilized isotropic pitch fibers were heated to 700°C to 800°C at a heating rate of 10°C per minute using a carbonization furnace under an inert atmosphere (N2 and Ar gas) and maintained for 1 hour.

[0065] The isotropic pitch fibers that have undergone the above stabilization step and carbonization process were activated using steam at 800°C for 30 minutes to 1 hour at a heating rate of 10°C / min and a flow rate of 0.4 to 1.2 g / min to produce activated carbon fibers.

[0066] Experimental Example 1

[0067] Measurement results of process characteristics, production yield, specific surface area, and pore distribution of activated carbon

[0068] To determine the stabilization reaction conditions, a thermal gravimetry (TG) was used to perform the test at an intermediate temperature range where weight gain occurs.

[0069] The specific surface area and pore distribution of the activated carbon fiber were measured by measuring the amount of nitrogen gas (N2) physically adsorbed on the surface and within the pores of the activated carbon fiber according to the change in relative pressure (P / P0) at the liquid nitrogen temperature (77K) of the activated carbon fiber.

[0070] The results of measuring the weight increase rate according to the above process conditions are as shown in Table 1 below.

[0071] heating rate Weight gain rate by stabilization temperature condition 260℃ 270℃ 280℃ 300℃ 0.5℃ / min +8.80% +10.07% +13.45% +16.67% 1℃ / min +6.25% +7.14% +7.20% +7.39%

[0072] Table 1 above shows the results of measuring the weight increase rate by condition during the stabilization phase.

[0073] According to the experimental results above, the weight increase rate of activated carbon fibers was measured as the heating rate was changed to 0.5℃ / min or 1℃ / min and the temperature of the stabilization stage reached by heating was changed to 260℃, 270℃, 280℃, or 300℃. It was confirmed that the degree of weight increase was greatest at a heating rate of 0.5℃ / min compared to 1℃ / min, and at a temperature condition of 300℃.

[0074] The weight loss rate according to temperature conditions in the preliminary carbonization process was measured. The experimental results are shown in Table 2 below.

[0075] division 700℃ 800℃ weight reduction rate -23.99% -29.93%

[0076] According to Table 2 above, it was confirmed that the degree of weight loss was smaller when the preliminary carbonization process was carried out under a temperature condition of 700°C compared to when the temperature in the preliminary carbonization process was maintained at 800°C.

[0077] The results of measuring the production yield under flow rate and temperature conditions when supplying steam during the activation process are as shown in Table 3 below.

[0078] Flow rate (g / min) transference number 800℃ 900℃ 0.4 64.63% 19.47% 0.8 79.89% 18.39% 1.2 61.02% 17.58%

[0079] According to Table 3 above, it was confirmed that the production yield was best at 800℃, a relatively low temperature condition, with a steam supply flow rate of 0.8g / min.

[0081] Preparation Example 2

[0082] In order to confirm the specific surface area characteristics according to the flow rate in the above activation process, an isotropic pitch fiber was prepared by stabilizing a pitch-based carbon fiber manufactured by melt spinning in the same manner as in Preparation Example 1 by maintaining it at 270°C at a heating rate of 0.5°C / min for 2 hours, and then carbonizing it by maintaining it at 700°C at a heating rate of 10°C / min for 1 hour, and then activating the isotropic pitch fiber at 900°C at a flow rate of 0.8 g / min for 30 minutes to produce an activated carbon fiber.

[0083] Preparation Example 3

[0084] In the above Preparation Example 2, the same stabilization and carbonization conditions were used, and activated carbon fibers were prepared by activating for 1 hour with a steam flow rate of 1.2 g / min during the activation process.

[0085] The results of measuring the specific surface area of ​​the activated carbon fibers prepared by the above Preparation Examples 2 and 3 are as shown in Table 4 below.

[0086] division Flow rate (g / min) Duration BET(m 2 / g) Example 2 0.8 30 minutes 1109.87 Comparative Example 1 1.2 1 hour 2429.50

[0087] According to Table 4 above, the activated carbon fibers using the isotropic pitch of the present invention all have a specific surface area of ​​1000 m² 2 It was confirmed that it was greater than / g.

[0088] In addition, according to Figures 1 and 2, it can be confirmed that the nitrogen adsorption effect is excellent.

[0089] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

Claims

Claim 1 A step of manufacturing isotropic pitch fibers by melt-spinning isotropic pitch using a 0.75 mm nozzle at 250°C to 260°C; a step of stabilizing the isotropic pitch fibers; and a step of carbonizing the stabilized isotropic pitch fibers. The method comprises the step of activating the carbonized isotropic pitch fiber to produce an activated carbon fiber, wherein the stabilization step involves increasing the temperature to 300°C at a rate of 0.5°C / min and stabilizing for 0.5 to 1.5 hours, the carbonization step involves increasing the temperature to 800°C at a rate of 10°C / min and carbonizing for 0.5 to 1.5 hours, and the activation step involves increasing the temperature to 800°C at a rate of 10°C / min under an inert gas atmosphere, supplying steam under a condition of 0.8g / min, and activating for 0.5 to 1.5 hours, wherein the activated carbon fiber exhibits an excellent removal effect due to the adsorption of harmful gases and a fast adsorption rate. Claim 2 In claim 1, the method for manufacturing activated carbon fibers for adsorbing harmful gases, wherein the activated carbon fibers have excellent adsorption performance for harmful gases composed of SOx, NOx, and mixtures thereof. Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 Activated carbon fiber for adsorbing harmful gases manufactured by the manufacturing method according to claim 1. Claim 7 A filter comprising activated carbon fibers according to paragraph 6.

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