KR20220033720A - Filter compising activated carbon/chitosan core-shell hybrid functionalized with amine - Google Patents

Abstract

The present invention provides a filter which comprises: a porous substrate; and a coating layer coated on the surface of the porous substrate and the surface of pores of the porous substrate, and containing amine functionalized activated carbon, wherein the amine-functionalized activated carbon is a core-shell hybrid having a core-shell structure in which the surface of activated carbon is coated with chitosan. According to the present invention, the filter contains a high content of activated carbon and has excellent structural stability, and the activated carbon is evenly distributed, thereby providing high efficiency of collecting harmful gases, in particular, providing excellent efficiency of collecting formaldehyde. The activated carbon functionalized with chitosan can chemically combine with volatile organic compounds to increase collection efficiency of harmful gases, can provide excellent effects of removing fine dust and ultrafine dust, bacteria, and fungi, and does not include carcinogenic substances harmful to the human body to provide excellent biocompatibility.

Description

Filter comprising activated carbon/chitosan core-shell hybrid functionalized with amine {Filter compising activated carbon/chitosan core-shell hybrid functionalized with amine}

The present invention relates to a filter comprising a porous substrate layer and a core-shell hybrid functionalized with an amine coating the surface of the substrate, and more particularly, for removing and collecting volatile organic compounds such as formaldehyde, bacteria and It relates to a filter for removing mold or fine dust.

Volatile organic compounds (VOCs) are a generic term for liquid or gaseous organic compounds that are easily evaporated into the atmosphere due to their high vapor pressure. It is not only a causative agent of air pollution and global warming, but also directly induces leukemia, central nervous system disorder and chromosomal abnormality in humans, and is known as a carcinogen. In particular, volatile organic compounds generated from peripheral devices closely related to daily life, such as building materials, household goods, and automobile materials, are not only harmful to health, but can also cause deterioration of product image. Recently, as the quality of life of human beings has improved, attention has been focused on the use of materials harmless to the human body or methods of suppressing or removing harmful substances, and international environmental regulations also limit the emission of volatile organic compounds (international environmental regulations aspect). The total content of the four major heavy metals: lead (Pb), cadmium (Cd), mercury (Hg), and hexavalent chromium (Cr6+) is regulated to be less than 100 ppm (green technology standards are less than 50 ppm).

When exposed to high concentrations of VOC, it causes acute disorders such as anesthesia (central nervous system suppression), dizziness, paralysis, and death. It becomes the causative substance of photochemical oxidant.

In Korea, it is regulated by various legislative bodies such as the Indoor Air Quality Control Act, the Chemicals Control Act, the Public Sanitation Control Act, the Industrial Safety and Health Act, and the School Health Act. There is a demand for product development of method and decomposition method.

Currently, as methods for treating volatile organic compounds, physicochemical treatment methods such as condensation, concentration, absorption and adsorption, biological treatment methods such as bio scrubbers and bio filters, and combustion methods such as oxidation are widely used.

In general, as a physicochemical treatment method, as a method for adsorption treatment of volatile organic compounds (VOCs), there are activated carbon, porous clay mineral, silica gel, activated alumina, and the like. However, a common feature of these adsorbents is that they have a very large surface area compared to their volume.

However, recently, there has been raised a problem of adversely affecting human cell activity, such as cytotoxicity, genetic toxicity, and human toxicity due to residual components of activated carbon. In addition, filters to which activated carbon is applied use acrylic as a binder, and because they usually cover the micropores inherent to activated carbon, they maintain minimal adhesion and induce a minimum reduction in gas collection efficiency (about 20 wt%). ) using a binder. Nevertheless, there is a problem that the efficiency is reduced by about 30% compared to the initial activated carbon, so it is necessary to develop a structurally stable filter while increasing the efficiency.

In addition, recently, the occurrence of fine dust and ultra-fine dust is increasing worldwide, and the damage caused by it is increasing, which is a problem. there is.

Accordingly, the inventors of the present invention have developed a multi-functional filter having excellent removal efficiency of fine dust/ultra-fine dust, bacteria and mold as well as harmful gases.

An object of the present invention is to provide a filter for removing, deodorizing or collecting volatile organic compounds with high efficiency, or for removing bacteria and mold or removing fine dust.

This will be described in detail as follows. Meanwhile, each description and embodiment disclosed in the present application may be applied to each other description and embodiment. That is, all combinations of the various elements disclosed in the present application fall within the scope of the present application. In addition, it cannot be seen that the scope of the present application is limited by the detailed description described below.

In one aspect of the present invention, the present invention provides a porous substrate; And coating the surface of the surface of the porous substrate and the surface of the pores of the porous substrate, and a coating layer comprising an amine-functionalized activated carbon (Amine Functionalized Active Carbon); including, wherein the amine-functionalized activated carbon is the surface of the activated carbon is made of chitosan It provides a filter that is a core-shell hybrid consisting of a coated core-shell structure.

Activated carbon (or activated charcoal), whose main component is carbon, has a porous structure and has a large surface area and thus has strong adsorption properties. And, there is a problem of low regeneration efficiency, and recently, problems such as toxicity to the human body due to residual components of activated carbon have been raised. The present invention provides a filter including a core-shell hybrid coated with chitosan on the outer and inner surfaces of the activated carbon, which can improve the collection efficiency while solving the problems of the activated carbon.

The filter may be used for collecting and removing volatile organic compounds, removing fine dust, and removing bacteria and mold.

In the present invention, the porosity of the activated carbon is preferably 20 to 99.9%, particularly preferably 30 to 50%.

In the present invention, the core-shell hybrid refers to particles having a core-shell structure in which chitosan surrounds and coats the surface of the activated carbon and the surface of the pores of the activated carbon. Activated carbon by chitosan -NH ₂ Since the functional group is introduced, the core-shell hybrid may include an amine functional group.

As such, the -NH ₂ functional group introduced by chitosan coated on the outer and inner surfaces of the activated carbon particles chemically bonds with volatile organic compounds such as aldehyde, hydrogen sulfide, ammonia, and acetic acid, thereby increasing the gas collection efficiency. In addition, the effect of removing bacteria and mold or the effect of removing fine dust is excellent. In addition, even after washing several times, the pore morphology and collection efficiency have excellent stability maintaining the same level as before washing. The structure of such a core-shell hybrid of the present invention is shown in FIG. 1 .

Referring to Figure 1, the -NH ₂ functionalization is made by coating the outer surface of the activated carbon and the inner surface of the pores of the activated carbon while maintaining, rather than covering, the pores of the activated carbon, and the core-shell hybrid includes pores and the size of the pores may be 2 to 30 nm, preferably 2 to 25 nm, more preferably 2 to 20 nm, but the scope of the present invention is not limited thereto.

In addition, in the core-shell hybrid, chitosan constituting the shell serves as a binder to maintain excellent bonding strength between particles. Specifically, strong hydrogen bonding by chitosan between the core-shell hybrid particles prevents desorption of the particles and can be evenly dispersed ( FIG. 2 ).

The chitosan refers to a high molecular compound obtained by deacetylating chitin, and the degree of deacetylation may be 75 to 85%, and the molecular weight may be 50000 to 190000 Da, but within the range that can achieve the object of the present invention. If it is, it is not limited to this.

In the present invention, the chitosan shell coating the surface of the activated carbon and the surface of the pores of the activated carbon may have a thickness of 0.01 to 2 nm, preferably 0.05 to 1.5 nm, more preferably 0.07 to 1.2 nm It may have a thickness of the size.

When activated carbon and chitosan are simply mixed or used in the form of a composite, the activated carbon is not uniformly distributed and is concentrated in some areas, which may weaken the mechanical strength of the entire filter. On the other hand, the core-shell hybrid structure of the present invention allows the activated carbon to be uniformly distributed, and thus the filter of the present invention can contain a high content of activated carbon, while maintaining excellent mechanical strength.

In the present invention, the coating layer can coat the surface of the porous substrate and the surface of the pores included in the porous substrate, whereby activated carbon can be evenly distributed on both the external and internal surfaces of the porous substrate, and the external and internal surfaces of the porous substrate The structure of the filter including the coating layer coating the surface is shown in FIG. 2 .

Referring to FIG. 2 , an activated carbon core-core-shell hybrid including a chitosan shell is evenly distributed over the entire surface (external and internal surfaces) of the porous substrate, and this structure prevents the activated carbon from being easily desorbed and aggregation occurs between the activated carbons. There is an advantage in that structural stability is high by preventing it.

As such, there is an effect of high efficiency in adsorbing harmful gases or organic volatile compounds due to the structural characteristics of high structural stability and evenly distributed activated carbon.

In the present invention, the porous substrate may include any porous substrate having pores, and may be an organic porous substrate, an inorganic porous substrate, or a combination thereof. The organic porous substrate may be polystyrene, polyethylene, polyurethane, cotton, wool, non-woven fabric, wool, cellulose, methyl cellulose, carboxymethyl cellulose, polyacetate, nylon, etc., and the inorganic porous substrate may be carbon fiber, ceramic, silicate, etc. and preferably, polyurethane as the porous substrate.

In the present invention, the porous substrate may be in the form of a sponge, preferably polyurethane in the form of a sponge.

In the present invention, the porous substrate may have pores having a size of 20 to 5000 μm, preferably, 50 to 3000 μm, and more preferably, pores having a size of 100 to 1000 μm. If the size of the pores is smaller than this, it is difficult to coat the coating layer properly, and at the same time, the air passage speed is slowed, resulting in a large differential pressure, and the collection efficiency of harmful gases, volatile organic compounds, or fine dust may be reduced. In addition, when the size of the pores is larger than this, the mechanical stability of the porous substrate may be deteriorated, and the air passage may be relatively short. The porosity of the porous substrate is preferably 60 to 99.9%, particularly preferably 70 to 96%.

In the present invention, the coating layer may contain 30 to 90% by weight of activated carbon, preferably 35 to 85% by weight, more preferably 30 to 80% by weight based on the total weight of the coating layer.

In the present invention, the coating layer may be included in 10 to 90% by weight, preferably 10 to 70% by weight, more preferably 10 to 50% by weight based on the total weight of the filter.

In the present invention, the filter of the present invention can deodorize, remove or collect harmful gases such as volatile organic compounds (VOC). In general, volatile organic compounds are liquid or gaseous organic compounds that are easily evaporated into the atmosphere due to their low boiling point (VOC). It is very diverse from gas to liquid fuel with a low boiling point, and hydrocarbons commonly used in life such as paraffin, olefin, and aromatic compounds can be applied. VOCs generate photochemical oxidizing agents such as ozone through a photochemical reaction with nitrogen oxides (NOx) in the atmosphere, thereby causing photochemical smog. Substances such as benzene are carcinogenic and very harmful to the human body. can be classified as odor-causing substances.

In the present invention, the volatile organic compound may include formaldehyde, acetaldehyde, acetic acid, hydrogen sulfide, ammonia, toluene, and the like.

In addition, the filter of the present invention has excellent structural stability and can collect fine dust or ultrafine dust, and has a sufficient size of pores to allow air to pass freely while air passage is long, so it can efficiently collect fine dust there is

In addition, since the filter of the present invention has an excellent effect of removing bacteria and mold, it can be used for removing bacteria and mold.

Compared to the conventional layer-by-layer or simple composite structure filter, the filter of the present invention has a problem in that pores and surface area are reduced and collection efficiency is reduced. The filter of the present invention includes an activated carbon core-chitosan shell As the coating layer containing the core-shell hybrid is coated on the surface of the porous substrate, the problem of the conventional filter is solved.

The filter of the present invention contains a high content of activated carbon and has excellent structural stability, and as the activated carbon is evenly distributed, the harmful gas collection efficiency is high, and in particular, the collection efficiency of formaldehyde is excellent.

In addition, activated carbon functionalized by chitosan may be chemically bonded to a volatile organic compound and the like to improve the collection efficiency of harmful gases.

In addition, the filter of the present invention is excellent in the effect of removing fine dust or ultrafine dust.

In addition, the filter of the present invention is excellent in antibacterial and antifungal properties, and does not contain carcinogenic substances harmful to the human body and thus has excellent biocompatibility.

1 and 2 are schematic views showing a core-shell hybrid structure according to the present invention.
3 is a schematic view showing the structure of a filter according to the present invention in the form of a core-shell hybrid coated on the surface of a porous substrate.
4 shows the TEM image results for analyzing the morphology of the core-shell hybrid of the present invention.
5 shows SEM images for analyzing surface morphology changes before and after functionalization with chitosan.
6 shows the results of analysis of changes in specific surface area, pore size and pore volume of the core-shell hybrid of the present invention.
7 is a comparison of SEM images of a porous substrate and a filter according to the present invention.
8 is a comparison of SEM images of pure activated carbon particles and a filter according to the present invention.
9 shows the results of analysis of formaldehyde absorption efficiency of the filter of the present invention.
10 shows the results of analysis of the first removal efficiency of the filter of the present invention.
11 shows the results of analysis of fine dust removal efficiency before and after washing of the filter of the present invention.
12 shows the results of pore morphology analysis before and after washing the filter of the present invention.

Hereinafter, the present invention will be described in more detail through examples. However, these examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

material

Activated carbon (SM Carbon, particle size range: 5.1-15.4 μm, average particle size: 9.2 μm, pore size: 2.44±0.134 nm) was obtained from SM Carbon Inc. In Korea, it was obtained and used. Low molecular weight chitosan (MW = 50000-190000, 75-85% deacetylation) was purchased from Sigma-Aldrich (United States) and used. All chemicals including glacial acetic acid, sodium hydroxide and organic solvents were purchased from Sigma-Aldrich and used without further purification.

<Example 1> Activated carbon core-core-shell hybrid preparation comprising a chitosan shell

Example 1-1: Core-shell hybrid preparation of activated carbon core/chitosan shell (90 wt%/10 wt%) (Chit/AC90)

After adding 0.4 g of chitosan and 3.6 g of activated carbon to 1 L of an aqueous solution having a pH of 2, the mixture was completely dissolved by stirring. Thereafter, the activated carbon solution was prepared by sufficiently dispersing through a Sonoreactor and adjusting with 5% aqueous ammonia or a basic solution to pH 9.

Thereafter, the activated carbon solution was freeze-dried to prepare core-shell hybrid nanoparticles (Chit/AC90) in powder form.

Example 1-2: Core-shell hybrid preparation of activated carbon core/chitosan shell (70 wt%/30 wt%) (Chit/AC70)

After adding 1.2 g of chitosan and 2.8 g of activated carbon to 1 L of an aqueous solution having a pH of 2, the mixture was completely dissolved by stirring. Thereafter, the activated carbon solution was prepared by sufficiently dispersing through a Sonoreactor and adjusting with 5% aqueous ammonia or a basic solution to pH 9.

Thereafter, the activated carbon solution was freeze-dried to prepare core-shell hybrid nanoparticles (Chit/AC70) in powder form.

Example 1-3: Core-shell hybrid preparation of activated carbon core/chitosan shell (50 wt%/50 wt%) (Chit/AC50)

After adding 2.0 g of chitosan and 2.0 g of activated carbon to 1 L of an aqueous solution having a pH of 2, the mixture was completely dissolved by stirring. Thereafter, the activated carbon solution was prepared by sufficiently dispersing through a Sonoreactor and adjusting with 5% aqueous ammonia or a basic solution to pH 9.

Thereafter, the activated carbon solution was freeze-dried to prepare core-shell hybrid nanoparticles (Chit/AC50) in powder form.

Example 1-4: Core-shell hybrid preparation of activated carbon core/chitosan shell (65 wt%/35 wt%) (Chit/AC35)

After adding 1.4 g of chitosan and 2.6 g of activated carbon to 1 L of an aqueous solution having a pH of 2, the mixture was completely dissolved by stirring. Thereafter, the activated carbon solution was prepared by sufficiently dispersing through a Sonoreactor and adjusting with 5% aqueous ammonia or a basic solution to pH 9.

Thereafter, the activated carbon solution was freeze-dried to prepare core-shell hybrid nanoparticles (Chit/AC50) in powder form.

<Example 2> Filter for collecting volatile organic compounds

Example 2-1: activated carbon core/chitosan shell (90 wt% /10 wt% )of core shell a hybrid Manufacture of filter for collecting volatile organic compounds containing

After the activated carbon solution prepared in Example 1-1 was diluted in half and sufficiently stirred, a polyurethane sponge (15-50 K, 50-100 PPI) was completely immersed in the diluted solution so that the solution was sufficiently absorbed. After that, it was dried in an oven at 70° C., and after complete drying, the above process was repeated 3 to 7 times, and finally washed with water and ethanol and dried to obtain a core-shell hybrid of a polyurethane sponge layer and an activated carbon core/chitosan shell. A filter including a coating layer containing

Example 2-2: Preparation of a filter comprising a core-shell hybrid of activated carbon core/chitosan shell (70 wt%/30 wt%)

After the solution prepared in Example 1-2 was diluted in half and sufficiently stirred, a polyurethane sponge (15-50 K, 50-100 PPI) was completely immersed in the diluted solution so that the solution was sufficiently absorbed. After that, it was dried in an oven at 70° C., and after complete drying, the above process was repeated 3 to 7 times, and finally washed with water and ethanol and dried to obtain a core-shell hybrid of a polyurethane sponge layer and an activated carbon core/chitosan shell. A filter including a coating layer containing

Example 2-3: Preparation of a filter comprising a core-shell hybrid of activated carbon core/chitosan shell (50 wt%/50 wt%)

After the solution prepared in Example 1-3 was diluted in half and sufficiently stirred, a polyurethane sponge (15-50 K, 50-100 PPI) was completely immersed in the diluted solution so that the solution was sufficiently absorbed. After that, it was dried in an oven at 70° C., and after complete drying, the above process was repeated 3 to 7 times, and finally washed with water and ethanol and dried to obtain a core-shell hybrid of a polyurethane sponge layer and an activated carbon core/chitosan shell. A filter including a coating layer containing

Example 2-4: Preparation of a filter comprising a core-shell hybrid of activated carbon core/chitosan shell (65 wt%/35 wt%)

After the solution prepared in Example 1-4 was diluted in half and sufficiently stirred, a polyurethane sponge (15-50 K, 50-100 PPI) was completely immersed in the diluted solution so that the solution was sufficiently absorbed. After that, it was dried in an oven at 70° C., and after complete drying, the above process was repeated 3 to 7 times, and finally washed with water and ethanol and dried to obtain a core-shell hybrid of a polyurethane sponge layer and an activated carbon core/chitosan shell. A filter including a coating layer containing

<Experimental Example 1> Surface analysis of filters including morphology analysis of core-shell hybrid nanoparticles

Analysis of the morphologies of pure activated carbon and the core-shell hybrids of Examples 1-1, 1-2 and 1-3 using a field emission scanning electron microscope (HR-TEM, JEM 3010, JEOL, Akishima, Japan) and the results are shown in FIG. 4 .

Referring to FIG. 4 , it can be confirmed that the core-shell hybrid of the present invention is a form in which chitosan is coated on the surface of an amorphous activated carbon in a core-shell shape.

<Experimental Example 2> Confirmation of specific surface area, pore size and volume change of core-shell hybrid nanoparticles

The surface morphology of pure activated carbon and porous substrate and the specific surface area, pore size and volume of the core-shell hybrids of Examples 1-1, 1-2 and 1-3 were measured by a specific surface area measuring device (BET, QD-SI/MP , Quantachrome, USA) was used to degas a 100 mg powder sample overnight, and then it was measured under He gas.

Pure Activated Carbon (Chit/AC100) Example 1-1 (Chit/AC90) Example 1-2 (Chit/AC70) Example 1-3 (Chit/AC50) specific surface area (m ² /g) 924.80±71.55 705.87±79.33 609.57±46.77 599.05±36.43 Pore size (nm) 2.44±0.134 2.28±0.211 2.31±0.119 2.36±0.183 Pore volume (cc/g) 0.384±0.023 0.32±0.037 0.286±0.037 0.278±0.035

Referring to Table 1 and Figure 6, the specific surface area of the core-shell hybrid was 76.3% and 65.9%, respectively, when chitosan was coated at a content of 10, 30, and 50 wt% compared to before (Chit/AC100) coated with chitosan. , decreased by 64.8%, pore size decreased by 6.6%, 5.3%, and 3.3%, respectively, and pore volume decreased by 21.9%, 25.5%, and 27.6%, respectively. The relatively small decrease in specific surface area compared to the amount of chitosan binder used shows maximization of functionality on the surface of activated carbon particles and minimization of decrease in specific surface area. In particular, the continuous reduction of the pore size and pore volume due to the additional use of the chitosan binder means that the binder molecules are also coated on the inner wall of the pores, which means that the functionalization to the inside of the pores is effectively achieved.

From these results, it was found that the chitosan was coated up to the inner surface of the pores while maintaining the pores of the activated carbon.

<Experimental Example 3> Surface analysis of a filter comprising a core-shell hybrid of an activated carbon core/chitosan shell of the present invention

The surface morphology of pure activated carbon, the porous substrate surface morphology, and the morphology of the filters prepared according to Examples 2-1, 2-2, and 2-3 were examined by field emission scanning electron microscopy (FE-SEM; MIRA II LMH microscope, Tescan , Czech Republic), and the results are shown in FIGS. 5 and 7 and 8 .

In addition, referring to FIG. 5 , 100%/chit 0% of activated carbon before functionalizing the activated carbon with chitosan has a sharply angled shape at the edge of the surface, whereas Examples 2-1 and 2 of activated carbon functionalized with chitosan In the core-shell hybrids of -2 and 2-3, the surface of the activated carbon was softened by chitosan coating the surface of the activated carbon, and it was found that the surface became softer as the content of chitosan increased.

Referring to Figure 7, there were no nanopores on the inner wall surface of the macropores of the porous substrate (Sponge), and after coating the activated carbon, the core-shell hybrid of the activated carbon core/chitosan shell was formed on the inner surface of the macropores of the porous substrate. It was also confirmed that the coating and the 2-20 nm nanopores of the activated carbon were preserved as they are.

Therefore, it was confirmed that, in the core-shell hybrid of the activated carbon core/chitosan shell of the present invention, the nano-sized pores of the activated carbon surface were maximally preserved while the surface was modified by coating the surface of the porous substrate.

In addition, referring to FIG. 8 , it was confirmed that there was no significant change in the surface shape of the pure activated carbon and the nanopore size of the activated carbon particles coated on the filter of the present invention.

Experimental example 4: pattern Activated carbon core/chitosan of the invention of the shell core shell a hybrid Analysis of harmful gas deodorization rate of filters including

Analysis of the toxic gas collection efficiency of the filter according to the present invention was performed in FITI and KCL, and the specific test conditions are as follows.

- Test piece: filter prepared according to Example 2-2 and Example 2-4 with a size of 10X10 cm

- Gas bag: 5L

- Gas volume in gas bag: 3L

Measurement time: after 2 hours

- Initial concentration: ammonia (100 ppm), acetic acid (50 ppm), formaldehyde (15 ppm), toluene (20 ppm), acetaldehyde (14 ppm)

- Deodorization rate (%) = ((Cb-Cs)/Cb)X100 (Cb: BLANK, concentration of test gas remaining in test gas bag after 2 hours; Cs: sample, remaining in test gas bag after 2 hours concentration of test gas)

Table 2 shows the formaldehyde deodorization rate results of the filters according to Examples 2-2 and 2-4 analyzed according to the conditions as described above.

test gas Chit/AC70 Chit/AC35 ammonia(%) >99.8 91.4 Acetic acid (%) 98.4 98.3 Formaldehyde (%) 91.7 32.7 toluene(%) >97.5 75.0 Acetaldehyde (%) >98.5 91.7

Referring to Table 2, in the filters of Examples 2-2 and 2-4 of the filter according to the present invention, the deodorization rates of ammonia, acetic acid, formaldehyde, toluene and acetaldehyde, which are harmful gases, were all 90% or more. In particular, it was confirmed that the activated carbon content of 70 wt% had an excellent effect in all aspects than 35 wt%, and particularly showed excellent properties in removing formaldehyde. These results mean that the filter of the present invention has an excellent effect to trap most of the formaldehyde in the atmosphere.

Experimental example 5: pattern Activated carbon core/chitosan of the invention of the shell core shell a hybrid Analysis of the absorption rate of harmful gas of the filter including

The absorption rate of the filter prepared according to Example 2-2 of the present invention was analyzed by a one-pass measurement method, and the results are shown in Table 3 and FIG. 9 . The one-pass measurement method is a method applied to an actual air purifier, etc., and is a method to measure realistic formaldehyde removal ability.

- Test piece: filter prepared according to Example 2-2 and Example 2-4 with a size of 5X5 cm

- Gas pipe: 1L

- Gas filling amount in gas pipe: 0.86L

Gas flow rate: 2.5m/sec

- Formaldehyde capture per 30 minutes: see Table 3

- Total collection amount = the amount of test gas collected by the specimen after 210 minutes)

Initial filling amount 30 minutes 60 minutes 90 minutes 120 minutes 150 minutes 180 minutes 210 minutes CS8 (AC45) 0.8689 mg 3.6598
mg 3.3145
mg 2.4053
mg 2.7391
mg 5.3171 mg 3.3039 mg 3.1994
mg

Referring to Table 3, it can be seen that the filter according to the present invention continuously absorbs formaldehyde at a level similar to the initial collection amount even after a period of at least 210 minutes.

In addition, referring to the blue curve of FIG. 9 , it was found that the filter according to the present invention had an excellent formaldehyde absorption efficiency of 300% or more compared to the conventional air purifier carbon filter (activated carbon applied).

Experimental example 6: Activated carbon core/chitosan of the present invention of the shell core shell a hybrid Containing carcinogenic organic solvents in filters containing

Analysis of antibacterial and antifungal properties of filters prepared according to Examples 2-2 and 2-4 of the present invention was performed at KOTITI, and the specific test conditions are as follows.

- Nonionic surfactant used: TWEEN 80 (0.05%)

- Proliferation value: Proliferation value of control (valid when Mb/Ma = 31.6 or higher)

Staphylococcus aureus: 43.3

Klebsiella pneumoniae: 120.0

- Reduced bacteriostatic value (S): log Mb - log Mc (difference in the number of viable cells in the processed sample versus the unprocessed sample)

- bacteriostatic reduction rate (%): (Mb- Mc)/Mb x 100) {Ma = number of viable cells immediately after inoculation of control; Mb = number of viable cells after 18 hours of incubation of the control; Mc = number of viable cells after 18 hours of incubation of the sample}

Table 4 shows the results of the antibacterial and antifungal properties of the filters according to Examples 2-2 and 2-4 analyzed according to the conditions as described above.

bacteria used Example 2-2 (Chit/AC70) Example 2-4 (Chit/AC35) antibacterial Staphylococcus aureus reduction rate (%) 99.9 99.9 Pneumonia reduction rate (%) 99.9 99.9 antifungal Chaetomiumglobosum (ATCC 6205) The area of the growth part of the mycelium recognized in the inoculated part of the sample or test piece is
Exceeds 1/3 of the total area The growth of mycelium is not recognized in the inoculated part of the sample or test piece. Aspergillusniger (ATCC 6275) Penicillium citrinum (ATCC 9849) Myrothecium verrucaria (ATCC 9095 / USDA 1334.2)

Referring to Table 4, it is confirmed that the filter according to the present invention has excellent antibacterial properties of 99% or more against Staphylococcus aureus and pneumococcus, and also has excellent antifungal properties.

Experimental example 7: pattern Activated carbon core/chitosan of the invention of the shell core shell a hybrid Containing carcinogenic organic solvents in filters containing

Whether the filter prepared according to Example 2-2 of the present invention contains a carcinogenic maintenance solvent was confirmed through solvent extraction and LG-MS/MS analysis, and the results are shown in Table 4 below.

Test Items unit limit of quantification Test result Test Methods 1,2-Benzisothiazol-3(2H)-one (BIT) mg/kg <5 non-detection Solvent extraction & LG-MS/MS analysis 5-chloromethylisothiazolinone (CMIT) <1 non-detection Methylisothiazolinone (MIT) non-detection 2-octyl-3(2H)-isothiazolone (OIT) <5 non-detection

Referring to Table 5, the filter of Example 2-2 contains 1,2-benzisothiazol-3(2H)-one (BIT), 5-chloromethylisothiazolinone (CMIT), known as carcinogenic substances. , methylisothiazolinone (MIT) and 2-octyl-3(2H)-isothiazolone (OIT) were all confirmed not to be detected.

Experimental example 8: pattern Activated carbon core/chitosan of the invention of the shell core shell a hybrid Analysis of fine dust removal efficiency of filters including

The fine dust removal efficiency of the KF80 combination filter (PU activated carbon filter/KF80 Filter combination filter) and the pure KF80 combination filter (Cord No. AFAC70CS30/KF80) including the filter manufactured according to Example 2-2 of the present invention The analysis was carried out, and the measurement conditions are shown in Table 6 below.

Measured wind speed: 08-1.0 m/sec PM 1.0 PM 2.5 PM 10 Concentration announced by the Ministry of Environment (μg/m ³ ) 65 138 Measured concentration (μg/m ³ ) 25.2 134.6 198.9 Actual concentration per particle (μg/m ³ ) 25.2 109.4 64.3

The results of the microcell removal efficiency analysis of the filter according to Example 2-2 and the combination filter of KF80 analyzed according to the conditions as described above are shown in FIG. 10 .

As can be seen in FIG. 10 , an excellent effect of about 150% removal efficiency was obtained when the filter of the present invention was included in comparison with the PM1.0 standard pure KF80 filter.

Experimental example 9: pattern Activated carbon core/chitosan of the invention of the shell core shell a hybrid Analysis of fine dust removal efficiency before and after washing of the included filter

Fine dust efficiency and pure KF80 combination filter (Cord No. AFAC70CS30 / The fine dust removal efficiency of KF80) was analyzed, and the measurement conditions are shown in Table 7 below.

Measured wind speed: 08-1.0 m/sec PM 1.0 PM 2.5 PM 10 Concentration announced by the Ministry of Environment (μg/m ³ ) - 16 34 Measured concentration (μg/m ³ ) 15.3 30.7 38.4 Actual concentration per particle (μg/m ³ ) 15.3 15.4 7.7

The results of the microcell removal efficiency analysis according to the conditions as described above are shown in FIG. 11 .

As can be seen in FIG. 11, when the filter of the present invention is included, compared to the pure KF80 filter based on PM1.0, an excellent effect of about 160% removal efficiency was exhibited, and the excellent initial collection efficiency even after washing 5 times has been shown to maintain

In addition, the morphology according to the number of washing of the filter of the present invention was analyzed using a field emission scanning electron microscope (HR-TEM, JEM 3010, JEOL, Akishima, Japan), and the results are shown in FIG. 12 .

As can be seen in FIG. 12 , the filter of the present invention was shown to maintain the pore morphology even after washing 5 times.

Although the above has been described with reference to the preferred embodiments of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. You will understand that you can.

Claims (5)

porous substrate; and
Including; coating the surface of the porous substrate and the surface of the pores of the porous substrate, the coating layer comprising an amine-functionalized active carbon (Amine Functionalized Active Carbon);
The filter wherein the amine-functionalized activated carbon is a core-shell hybrid having a core-shell structure in which the surface of the activated carbon is coated with chitosan. According to claim 1,
The filter is a filter for collecting and removing volatile organic compounds, removing fine dust, and removing bacteria and mold. According to claim 1,
The core-shell hybrid includes pores having a size of 2 to 30 nm, and the chitosan shell has a thickness of 0.01 to 2 nm, a filter. According to claim 1,
The porous substrate is selected from the group consisting of polystyrene, polyethylene, polyurethane, cotton, wool, nonwoven fabric, wool, cellulose, methylcellulose, carboxymethylcellulose, polyacetate, nylon, carbon fiber, ceramic and silicate, filter . According to claim 1,
The coating layer is included in 10 to 90% by weight based on the total weight of the filter, filter.

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