JPH0796129A - Air purifying filter unit - Google Patents

Abstract

PURPOSE:To provide an air purifying filter unit excellent in ammonia adsorption performance, little in pressure loss and low in manufacturing cost by electrically flocking active carbon fiber on which persimmon fruit juice is stuck to a porous base material. CONSTITUTION:Active carbon fiber 3 on which persimmon fruit juice is stuck is electrically flocked to a porous base material 5 (for example, formed polyurethane). The base material 5 is a sheet one having 0.5-50mm thickness and the average length of the active carbon fiber 3 is 0.05-5mm. Further, the carrying quantity or the sticking quantity of persimmon fruit juice to the active carbon fiber is about 2-50%, preferably about 15-30% (as solid content) of the weight of the active carbon fiber, and the METSUKE weight (a weight unit, g/m<2>) of the active carbon fiber on the porous base material is preferably about 50-500g/m<2>. As a result, an air purifying filter unit excellent in ammonia adsorption performance and little in pressure loss and low in manufacturing cost is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air cleaning filter unit having excellent deodorizing and deodorizing properties, particularly deodorizing and deodorizing properties by removing ammonia.

[0002]

2. Description of the Related Art As an air purifying filter unit or adsorbent used in an air purifier, an air conditioner with an air purifier, etc., for example, a porous base material such as urethane foam is bonded to a powdered activated carbon by an adhesive ( An adsorbent having an average particle diameter of about 0.03 to 0.1 mm attached is commercially available. With this type of adsorbent, the particle size of activated carbon is small, so if you try to increase the basis weight, the amount of adhesive also increases, so the pores of activated carbon are blocked, and the adsorption capacity exceeds a certain value. It cannot be increased. On the other hand, when the amount of adhesive is reduced, the amount of activated carbon dropped off becomes so large that it cannot be put to practical use.

When granular activated carbon (average particle size of about 0.5 to 2 mm) is used instead of the above powdered activated carbon,
Since the particle size increases and the surface area decreases, the adsorption rate decreases and the particles easily fall off. Furthermore, when attempting to adhere in multiple layers to a porous substrate, a very large amount of adhesive is required, so that the pores of activated carbon are blocked.
Adsorbents using activated carbon fiber (hereinafter referred to as ACF) paper or felt are also known. However, ACF paper cannot be used as a normal deodorizing filter because it has a high pressure loss due to its too high density. The same applies to the felt of the ACF.

[0006] A thin adsorbent obtained by processing ACF paper into a honeycomb and slicing honeycomb corrugated cardboard into thin pieces has a small pressure loss and a large ACF basis weight, but the processing cost is high because of the large number of processing steps. There is a problem that it becomes extremely high.

Japanese Examined Patent Publication No. 57-31453 proposes an adsorbent in which NCF in the constituent elements is 1% or more, a specific surface area is 300 m ² / g or more, and a fiber length of 0.5 to 1 mm is implanted with ACF. There is. However, this adsorbent has a problem in that it has a low adsorption characteristic for ammonia, which is one of the main components of night odor.

Persimmon juice has a deodorizing or deodorizing effect on odors from various sources, for example, Japanese Patent Publication No. 3-6145.
It is described in Japanese Patent No. 7 and is publicly known. However, it is difficult to say that the deodorizing performance of the use means described in this publication is satisfactory. For example, according to the disclosure of this publication, persimmon juice is adsorbed on a porous unglazed material, or even when used by impregnating a fibrous material such as paper, a sufficient deodorizing or deodorizing effect is not exhibited, and The duration of its effect is also relatively short.

[0007]

SUMMARY OF THE INVENTION Therefore, the main object of the present invention is to provide an air purification filter unit which has excellent ammonia adsorption performance, low pressure loss, and low manufacturing cost.

[0008]

Means for Solving the Problems As a result of intensive studies in view of the problems of the prior art as described above, the present inventor has carried persimmon juice on activated carbon fibers having specific pore characteristics,
It has been found that when this is electroflocked on a porous substrate, an air cleaning filter unit having excellent adsorption performance for aldehydes as well as ammonia, low pressure loss, and low manufacturing cost can be obtained.

That is, the present invention provides the following air purifying filter unit: 1 An air purifying filter characterized in that activated carbon fibers impregnated with persimmon juice are electro-implanted on a porous substrate. unit.

2. The porous substrate has a thickness of 0.5 to 50 mm
Item 2. The air cleaning filter unit according to Item 1, which is a sheet-shaped material.

3 The average length of the activated carbon fiber is 0.05 to
Item 3. The air cleaning filter unit according to item 1 or 2, which has a size of 5 mm.

The persimmon juice used in the present invention can be obtained by, for example, squeezing or crushing raw persimmon fruits from which seeds have been removed, if necessary, in the same manner as in the production of ordinary juices, and separating and recovering the juice. can get. The type of persimmon may be either sweet persimmon (complete sweet persimmon or incomplete sweet persimmon) or astringent persimmon (complete perfect persimmon or incomplete sweet persimmon). The degree of maturity of persimmon is not particularly limited, but unripe fruits are preferable. This is because the sugar content increases as the fruit ripens, and the amount of the deodorizing or deodorizing active ingredient relatively decreases. In addition, persimmon juice may be used after removing sugars that exert little deodorizing or deodorizing effect or by concentrating to increase the concentration of the active ingredient. In the present specification, not only the fruit juice itself separated from the fruit, but also sugar juice removed from the fruit juice, concentrated fruit juice, and additives to prevent alteration of the active ingredient in the fruit juice (antioxidant "Persimmon juice liquid", including those with added preservatives, preservatives, antifungal agents, etc.

The origin of ACF used in the present invention is not particularly limited, and it may be any of coal-based, petroleum-based, phenolic resin-based, PAN-based, cellulose-based and the like.

The ACF used in the present invention is not particularly limited, but usually has a fiber diameter of about 5 to 30 μm, an average fiber length of about 0.05 to 5 mm, and a pore radius of 5 to 2.
0 angstrom, specific surface area 500-2000m
It is preferable to use one having a concentration of about ² / g. In the ACF used in the present invention, its length is important. When the average fiber length is less than 0.05 mm, the ratio of covering with the adhesive increases, the ratio of closing the pores increases, and the basis weight decreases. On the other hand, the average fiber length is 5 mm
When it exceeds the above range, it becomes difficult to plant hair on the porous substrate, and thus the basis weight cannot be increased. In addition, the rate at which the long fibers block the void portion of the porous substrate increases, and the pressure loss increases. The average fiber length of the ACF is more preferably about 0.1 to 2 mm, particularly preferably about 0.3 to 0.7 mm, and the fiber length distribution is particularly preferably within ± 0.2 mm.

The amount of persimmon juice carried or impregnated (as solid content) with respect to ACF is about 2 to 50% of the weight of ACF.
More preferably about 5 to 40%, still more preferably 15
It is about 30%.

[0016] Supporting or attachment of persimmon juice to ACF is not particularly limited, and it can be carried out by any method such as impregnating persimmon juice with ACF or spraying persimmon juice onto ACF.

The porous substrate not only functions as a support for the ACF but also as a filter for the fluid to be treated. As the porous substrate, a foamed resin (for example,
Polyurethane foam, polypropylene foam, polyethylene foam, modified polyphenylene oxide, foam acrylonitrile-butadiene-styrene resin, foam unsaturated polyester, etc.), mesh sheet (metal, resin, etc.), perforated plate (metal, resin, etc.) Can be mentioned. Among these porous substrates, the ones made of a foamed resin are more preferable, and the foamed polyurethane is more preferable, because the amount of ACF flocking per filtration area can be increased. The size, shape, etc. of the porous substrate are not particularly limited, but the thickness is 0.5 to
It is preferable that the sheet has a shape of about 50 mm.

The basis weight of ACF with respect to the porous substrate is not particularly limited, but is preferably about 50 to 500 g / m ² . When the basis weight is less than 50 g / m ² , the adsorption performance is not sufficiently exhibited, whereas
If it exceeds 0 g / m ² , the manufacturing cost will increase,
Also, the pressure loss increases.

The air cleaning filter unit comprising the flocked adsorbent according to the present invention can be manufactured by an electric flocking method such as an electrostatic flocking method. In electrostatic flocking, the down method or the up method can be adopted, or both can be used together.

FIG. 1 schematically shows a cross-sectional view of an example of a manufacturing apparatus by the down method for manufacturing a flocked adsorbent by dropping a flocked material (ACF in this case).

In the apparatus shown in FIG. 1, the hopper 1 containing the ACF 3 is vibrated to drop the ACF. On the other hand, a porous substrate 5 having an adhesive (for example, an aqueous urethane resin liquid) applied on its surface
Are arranged on electrodes 9 (for example, electrodes made of wire mesh) connected to the high voltage generator 7. The high voltage generator 7 is
Further, it is connected to the upper electrode 11 and the lower electrode 13. When manufacturing the flocked adsorbent, the ACF is dropped in a strong electric field during corona discharge to flock the ACF in an upright state with respect to the porous substrate 5. The potential difference between the electrodes 9 and 11 is usually 1000-300.
It is about 00 KV, and more preferably 3000 to 100
It is about 00 KV. If the potential difference is too low, AC
It becomes difficult for F to stand upright on the porous base material 5, and when it is too high, it becomes difficult to uniformly implant ACF on the surface of the porous base material 5.

[0022]

According to the present invention, the persimmon juice liquid previously supported on the activated carbon fiber has a large outer surface area specific to the activated carbon fiber, a large specific surface area, and pore characteristics different from those of the granular activated carbon (for example, pores). Due to the radius distribution, the surface characteristics of the pores based on the difference in the pore structure, etc.), it reacts specifically with the odorous components such as ammonia and aldehydes adsorbed on the activated carbon fiber, and efficiently removes the odorous components. Disassemble and remove.

Further, the deodorizing or deodorizing effect of the persimmon juice liquid is maintained for a longer time.

Further, in the air cleaning filter unit according to the present invention, unlike the conventional product using powdered activated carbon or granular activated carbon, the ratio of ACF buried in the adhesive is reduced, so that the ratio of effective pores available for adsorption is reduced. As it increases, a large amount of ACF can be densely planted. Therefore, it is possible to obtain an adsorbent having a high adsorption capacity utilizing the high adsorption rate of ACF. In addition, ACF hardly falls off from the porous substrate. Further, the pressure loss during the adsorption operation is significantly reduced as compared with the air cleaning filter unit made of ACF felt. Such an air cleaning filter unit is extremely useful, for example, in the following applications.

-Deodorizing filter for air cleaning-Deodorizing filter for hot air heaters and air conditioners-Ozone removing filter-Other various deodorizing filters-Dust removing filter

[0026]

EXAMPLES Examples and comparative examples will be shown below to further clarify the features of the present invention.

Example 1 Pitch-based AC cut into chips of 0.3 to 0.7 mm
100 parts by weight of F (trademark "Adol A-10", manufactured by Adol Co., Ltd., specific surface area 1000 m ² / g) and 20 parts of persimmon juice liquid (trademark "Pancil SH-10L", manufactured by Release Kagaku Kogyo Co., Ltd.) It was immersed in 1000 parts by weight of an aqueous solution diluted to 5% for 5 seconds, drained, dried at 105 ° C. for 1 hour, and impregnated. From the difference in weight of ACF before and after the impregnation, it was confirmed that the amount of persimmon juice to be impregnated was 25 parts by weight (as solid content) relative to 100 parts by weight of ACF.

On the other hand, urethane foam (100 mm × 10
(0 mm × 5 mm), an aqueous urethane resin solution was thinly applied with a spray gun, and persimmon fruit juice impregnated ACF was electro-flocked using the device shown in FIG.

The product thus obtained was cut into a sample having a diameter of 38 mm and hung in a container having a capacity of 22 liters at a temperature of 25 ° C., and ammonia was adsorbed to the sample while internally circulating a gas having an initial ammonia concentration of 100 ppm. . The residual amount of ammonia after 20 minutes was 5%, which confirmed that the adsorbent had an excellent deodorizing ability.

The pressure loss at 25 ° C. was as shown by line A in FIG. In addition, in FIG.
² of adsorbent made of 50 g / m ² of ACF felt (pitch-based ACF similar to that in Example 1 is made into felt)
The pressure loss at 5 ° C. is shown as line B. The excellent performance of the flocked adsorbent according to the invention is evident.

Comparative Example 1 Example 1 except that coconut husk activated carbon (average particle size 0.3 mm) having a specific surface area of 1000 m ² / g was used instead of ACF.
An adsorbent was manufactured according to

In order to set the basis weight to 150 g / m ² ,
Despite the fact that a large amount of adhesive was required as compared with Example 1, the dropout of activated carbon was remarkable.

Comparative Example 2 An adsorption test of ammonia was carried out in the same manner as in Example 1 except that PAN-based ACF (nitrogen content 5.8%) having a nominal specific surface area of 1000 m ² / g which was not impregnated with persimmon juice was used. . However, the temperature during the test was 24 ° C.

The results after the lapse of a predetermined time are as shown in Table 1. In this table, the numerical values after the passage of time indicate the residual concentration (%) when the initial concentration of ammonia is 100%.

[0035]

[Table 1]

It is clear that the ammonia adsorption performance is significantly inferior to that of Example 1.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing an example of a manufacturing apparatus and a manufacturing method for a flocked adsorbent according to the present invention by a down method.

FIG. 2 is a graph showing a comparison of ammonia adsorption performance between an adsorbent according to the present invention and a comparative adsorbent.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Hopper 3 ... ACF 5 ... Porous base material 7 ... High voltage generator 9 ... Electrode 11 ... Upper electrode 13 ... Lower electrode

Front page continued (72) Inventor Takeshi Maeda 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Prefecture Osaka Gas Co., Ltd. (72) Inventor Susumu Fujita 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka No. within Osaka Gas Co., Ltd.

Claims (3)

[Claims] 1. An air-cleaning filter unit characterized in that activated carbon fibers impregnated with persimmon juice are electro-flocked on a porous substrate. 2. The air cleaning filter unit according to claim 1, wherein the porous substrate is a sheet material having a thickness of 0.5 to 50 mm. 3. The activated carbon fiber has an average length of 0.05 to 5 m.
The air cleaning filter unit according to claim 1 or 2, wherein m is m.