JPH0724256A - Deodorant - Google Patents

Abstract

PURPOSE:To obtain excellent deodorizing performance for both of acid and basic gases and to maintain an odoreless level for a long time by adding a photocatalyst on the surface of an adsorbent such as activated carbon with addition of an acid gas adsorptive additive and a basic gas adsorptive additive. CONSTITUTION:First, a base sheet comprising an adsorptive layer 1 in which acid adsorptive activated carbon and basic adsorptive activated carbon are combined and a layer on which a photocatalyst is to be deposited is produced by wet forming method. In this process, for example, when an activated carbon fiber 2 with addition of a basic gas adsorptive additive and an activated carbon fiber 3 with addition of an acid gas adsorptive additive are used, these fibers are mixed in a proper mixing ratio, mixed with a binder and a fiber 6, and then formed into a paper state by wet paper making method to obtain the adsorptive layer 1. On the other hand, a layer comprising only the fiber 6 and a binder is formed into a paper state by the same paper making method to obtain a photocatalyst carrier layer 4. This layer is laminated with the adsorptive layer 1. Then a slurry of fine particles of a photocatalyst 5 is applied on the photocatalyst carrying layer by spray coating and dried by heating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorizing agent which is excellent in deodorizing performance of acidic, basic and neutral gases in a gas phase and which maintains the performance for a long period of time, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Generally, activated carbon is widely used to remove a bad odor, but since physical adsorption is used as a deodorizing principle, it is difficult to maintain long-term performance. Therefore, in JP-A-1-189322, a method of combining an adsorbent and a photocatalyst is proposed, and the life of deodorizing performance is prolonged, but it is irritating at low concentrations of basicity, acid gas, etc. The deodorization level is not high enough to deodorize certain substances.

The effect of this method is to decompose the odorous components in the activated carbon with a photocatalyst to prolong the life of the activated carbon, or the photocatalyst itself decomposes the odorous components to comprehensively maintain the deodorizing effect for a long period of time. is there. However, as long as normal activated carbon is used, neutral odor gas deodorization is the main constituent, and it is difficult to satisfy the deodorization of acidic and basic gases which are naturally odor sources. This is a fatal defect for deodorants. All the gas needs to be decomposed quickly using only the photocatalyst, but depending on the odor component, the decomposition speed may be slow, and the desired rapid deodorization depends on the adsorption speed due to the fine pores of the activated carbon. In that sense, the deodorizing performance basically depends largely on the performance of the activated carbon.

[0004]

Therefore, an object of the present invention is to provide a deodorant having excellent deodorizing performance against acidic and basic gases and exhibiting outstanding performance as compared with conventional combinations. Is to provide.

[0005]

The present invention relates to a deodorant obtained by adding a photocatalyst to the surface of a layer of an adsorbent such as activated carbon impregnated with an acidic gas adsorptive adhesive and a basic gas adsorptive adhesive. is there.

As the acidic gas adsorptive adhesive, 3-
Aminopropyltrihydrosilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, dimethyltrimethyl-silylamine, N- (β- Amino group-containing organic substances such as aminoethyl) -γ-aminopropyl-trimethoxysilaneaniline and toluidine may be used.

The basic gas adsorptive adhesive is L
-Tartaric acid, succinic acid, maleic acid, citric acid, gluconic acid, malic acid, fumaric acid, glutamic acid, glutaric acid,
m-Hydroxybenzoic acid, pimelic acid, picolinic acid, itaconic acid, adipic acid, salicylic acid, glyceric acid, gallic acid and the like can be used.

The acid gas adsorptive adhesive and the base gas adsorptive adhesive are separately attached to an adsorbent such as activated carbon,
These two kinds of impregnating agents may be used together or may be impregnated with the same adsorbent such as activated carbon. Further, it is possible to use an adhesive having both an acid gas adsorbing property and a basic gas adsorbing property. Various metal oxides such as cobalt oxide, copper oxide, nickel oxide and iron oxide can be used as such an adhesive.

As the photocatalyst, titania, WO ₃ , F
e ₂ O ₃ or the like can be used.

As the adsorbent such as the activated carbon, activated carbon fiber (hereinafter sometimes referred to as "ACF"), powdered activated carbon, granular activated carbon, zeolite, silica gel or the like can be used.

A cross-sectional model view of the deodorant of the present invention is shown in FIG. The structure and manufacturing method of the model will be described with reference to this figure.
First, a base sheet comprising an adsorption layer in which acid / basic adsorptive activated carbon is combined and a layer on which a photocatalyst is to be supported (hereinafter referred to as "photocatalyst supporting planned layer") is prepared by wet molding.

In this case, for example, when the activated carbon fiber having the basic gas adsorptive adhesive and the activated carbon fiber having the acidic gas adsorptive adhesive are used, these are mixed at an appropriate ratio to form a binder and a binder. The fibers are mixed and shaped into a paper by a wet papermaking method to form an adsorption layer. On the other hand, a layer consisting of fibers and a binder is formed into a paper shape by the same papermaking method to form a photocatalyst-supporting layer, which is attached to the adsorption layer. Next, the photocatalyst fine particle slurry may be spray-coated on the photocatalyst-supporting layer and dried by heating.

The structure shown in the model of FIG. 1 is a simple type of model in which the photocatalyst is directly coated on the adsorption layer without providing the photocatalyst supporting layer. Although this has a slight increase in pressure loss (about 20%), it has the same performance as the model and is advantageous in terms of manufacturing, so it is effectively used according to the application.

The point to be noted in the production of this product is that the photocatalyst surface must be kept in an active state at all times. Therefore, unlike the present production method, if the photocatalyst surface is subjected to a functional group attachment treatment, Therefore, the decomposition effect is significantly deteriorated. In addition, an appropriate binder is required in order to prevent the base sheet from collapsing when it is coated with a photocatalyst, and the functional groups of the adsorption layer are not easily removed by the water content of the coating solution. ACF to functional group by drying in advance
It is necessary to fix them in the pores, but the manufacturing process of the product of the present invention is configured to satisfy these, and sufficiently fulfills each role, so that excellent performance unprecedented can be realized. To do.

In FIG. 1, 1 is an adsorption layer, 2 is a basic gas adsorption type activated carbon fiber, 3 is an acid gas adsorption type activated carbon fiber, 4 is a photocatalyst supporting layer, 5 is a photocatalyst, 6 is a fiber, and 7 is an ultraviolet ray. Is the source.

As the binder, water-soluble polymers such as vinylon, acrylic emulsion, vinyl chloride, acrylic styrene copolymer, ether ester polyurethane resin, polyester urethane, urethane resin, polyvinyl alcohol and acrylic can be used.

As the fibers, synthetic fibers such as rayon fibers, polyester fibers, nylon fibers, pulp, linter pulp, Manila hemp and the like can be used.

In the deodorant of the present invention, the amount of the photocatalyst and the type and amount of the adsorbed adsorbent can be adjusted according to the component and the concentration of the target odor, and the place of use and the life can be widely selected.

An example of use of the present invention is shown in FIG. In (a) of this figure, 11 is a photocatalyst layer and 12 is an adsorption layer. In (c) of this figure, 13 is a deodorant processed product, 1
4 is an ultraviolet lamp, 15 is an arrow indicating the flow direction of the odorous component, 16 is a fan, and 17 is a case.

[0020]

According to the present invention, most of the odorous gas can be converted into a photocatalyst by combining a photocatalyst with an adsorbent having an acidic gas adsorptive adhesive and an adsorbent having a basic gas adsorptive adhesive. By decomposing and deodorizing and adsorbing a part of the residual odor with each adsorbent, the odorless level can be maintained for a long period of time.

[0021]

【Example】

(Example 1) An adsorption layer of the model shown in Fig. 1 was prepared as follows. The acid gas adaptive activated carbon impregnated material, 3-aminopropyltriethoxysilane hydrosilane (hereinafter, referred to as "AS"), and the carrier using the activated carbon fiber (ACF) having a specific surface area 800~1500m ² / g, AS 0.01 to 0.
A 1 mol / L aqueous solution is prepared, and the above carrier is AS
1 to 10 times the amount of the mixture was added, and the mixture was impregnated for 1 hour with stirring with a stirring blade to react. Then, vacuum suction filtration was performed, and drying was performed at 120 ° C. for 3 hours to obtain an acid gas adsorption type activated carbon. Further, L-tartaric acid was used as the impregnating agent for the basic gas adsorption type activated carbon, and the above ACF was used as the carrier.
-After adjusting tartaric acid to an aqueous solution of 0.2 mol / L, the same operation as the above acidic gas adsorption type activated carbon was carried out to obtain a basic gas adsorption type activated carbon.

Next, both impregnated ACFs were mixed in a weight ratio of 1: 1 and 5 wt% of binder and 15 wt% of the material were mixed.
% Of synthetic fibers were mixed and formed into a paper by a wet papermaking method, which was used as an adsorption layer. At this time, a layer consisting only of synthetic fibers and a binder was formed into a paper by the same papermaking method, and was bonded to the adsorption layer, which was used as a photocatalyst-supporting layer. In the wet papermaking method, the raw materials are mixed in water and formed into a thin sheet with a round net, a flat net, or the like, and thereafter,
It is dried by a drum dryer at 120 ° C. for 10 minutes. The binder used was vinylon and the synthetic fiber was rayon.

The photocatalyst supported on the base sheet consisting of the adsorption layer and the photocatalyst-supporting layer obtained by the above manufacturing method will be described below. Titania was used as the photocatalyst. Its crystallite size is 80 ~ 200Å, particle size is 0.5μm ~
It was 2.5 μm. Then, the titania was adjusted to a slurry having a concentration of 5 wt%, the base sheet was coated by spraying, and then dried at 100 ° C. for 2 hours.

As a result, the structure shown in the model of FIG. 1 is obtained.
The deodorant of this example was obtained. In addition, the deodorant specifications of this example
The adsorption layer is 120 g / m², The photocatalyst support layer is 40g
/ M ²The amount of titania carried is 60 g / m², Thickness is 1
mm. Also, the pressure loss is 30 mmH at a wind speed of 30 cm / s.
₂It was O.

FIG. 3 is a flow chart showing the manufacturing process of the model of FIG. 1 in an easy-to-understand manner.

The role of the adsorption layer in this deodorant is as follows:
The acidic gas is adsorbed by the amino group (basic functional group) of the adhesive agent AS, and the basic gas is adsorbed by the carboxyl group (acidic functional group) of the adhesive agent L-tartaric acid. In addition, since the ACF pores are still fully utilized in the one subjected to the impregnation treatment by the above-mentioned manufacturing method, the adsorption of neutral gas is maintained at a satisfactory level without any problem.

Next, in order to show the effect of the product of the present invention, the removal rate of the single component gas was measured. In the measurement, first, a deodorant (2.5 × 13.5 cm) is placed at 25 ° C. in a closed chamber in which a single component gas having an initial concentration (R) is continuously flowed to adsorb and decompose the single component gas. . At this time, the deodorant is constantly illuminated by the ultraviolet lamp (20 W). And
The residual concentration (Q) of the single component gas after passing through the deodorant is measured by a gas chromatograph (GC-9A, Shimadzu Corporation). The removal rate (S) of the single component gas is calculated by the following formula.

S (%) = 100 × (RQ) / R

The various single-component gases are acetaldehyde (CH ₃ CHO), toluene (C ₇ H ₈ ) and ammonia (NH ₃ ). The initial concentration of these was 100 ppm. The ammonia concentration was measured by a detector tube and the other gases were measured by gas chromatography.

For comparison, the gas removal rate was also measured for the deodorant using untreated activated carbon in the same manner as above. The product of the present invention used for the measurement sample is AS0.0
An impregnated ACF having an impregnation concentration of 1 mol / L, L-tartaric acid of 0.05 mol / L and having a specific surface area of 1200 m ² / g as a carrier was used.

The results of this measurement are shown in FIG. From FIG. 4, it can be seen that in the removal rates of acetaldehyde, which is an acidic gas, and ammonia, which is a basic gas, the product of the present invention has a better removal rate than the comparative example. It is also clear that there is no problem with the removal rate of toluene, which is a neutral gas.

As can be seen from the above results, in order to improve the deodorizing performance of gas components other than the neutral gas, it is clear that the use of high-performance activated carbon is an important factor. It was

(Example 2) In this example, instead of the AS used in Example 1, the following various amino group-containing organic substances were used to prepare a deodorant in the same manner as in Example 1, and the gas thereof was used. The removal rate was measured. In all cases, the same effect as in Example 1 could be obtained.

As the above-mentioned amino group-containing organic matter, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, N-β (aminoethyl)-
γ-aminopropyltrimethoxysilane, dimethyltrimethyl-silylamine and N- (β-aminoethyl)-
γ-Aminopropyl-trimethoxysilane was used.

Example 3 In this example, instead of the L-tartaric acid used in Example 1, succinic acid, maleic acid,
Example 1 and citric acid, gluconic acid, malic acid, fumaric acid, glutamic acid, glutaric acid, m-hydroxybenzoic acid, pimelic acid, picolinic acid, itaconic acid, adipic acid, salicylic acid, glyceric acid and gallic acid, respectively. A deodorant was prepared in the same manner and the same evaluation was performed. As a result, the same effects as those of Example 1 could be obtained.

(Embodiment 4) In this embodiment, in Embodiment 1,
Instead of the photocatalytic titania used, WO ₃as well as
Fe₂O₃To produce a deodorant in the same manner as in Example 1.
Then, the same evaluation was performed. As a result, all examples
The same effect as that of No. 1 could be obtained.

Example 5 In this example, instead of AS used in Example 1, aniline and toluidine, which are aromatic amines, were used to prepare a deodorant in the same manner as in Example 1, and the same deodorant was prepared. An evaluation was performed. As a result, the same effects as those of Example 1 could be obtained.

Example 6 In this example, instead of the AS and L-tartaric acid used in Example 1, ACFs carrying fine particles of various metal oxides were used, respectively, and deodorization was performed in the same manner as in Example 1. The agent was prepared and its gas removal rate was measured.
As a result, the same effects as those of Example 1 could be obtained.

The metal oxides are cobalt oxide, copper oxide, nickel oxide and iron oxide. The supporting method is to prepare an aqueous solution using a compound of a nitrate or oxide of the metal, impregnate it with ACF, and then dehydrate, dry and calcine for 2 hours at 300 ° C. It is intended to support fine particles of metal oxide.

Example 7 In this example, the carrier AC
Instead of F, powdered activated carbon, granular activated carbon, zeolite and silica gel were used to prepare the deodorant. Others are the same as in the first embodiment. Also in this example, the same effects as those in Example 1 could be obtained.

Example 8 In this example, instead of the binder or synthetic fiber used in Example 1, the following various raw materials were used, and a deodorant was prepared in the same manner as in Example 1 The gas removal rate was measured. As a result, the same effects as those of Example 1 could be obtained.

As the binder, water-soluble polymers such as acrylic emulsion, vinyl chloride, acrylic styrene copolymer, ether-ester polyurethane resin, polyester urethane, urethane resin, polyvinyl alcohol, and acrylic were used.

As substitutes for the above synthetic fibers, polyester, nylon, pulp, linter pulp and Manila hemp were used, respectively.

[0044]

According to the present invention, not only neutral gas but also acidic gas and basic gas can be deodorized for a long period of time.

[Brief description of drawings]

FIG. 1 is a model view of a cross section of the deodorant of the present invention.

FIG. 2 is a view showing an example of using the deodorant of the present invention.

FIG. 3 is a flowchart of a deodorant manufacturing process in Example 1.

FIG. 4 is a single component gas removal rate in Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Adsorption layer 2 ... Basic-gas-adsorptive-adhesive-additive-active-carbon-fiber 3 ... Acid-gas-adsorptive-adhesive-additive-active-carbon-fiber 4 ... Photocatalyst-supporting-layer 5 ... Photocatalyst

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B01D 53/81 (72) Inventor Okamoto ▲ Kuni ▼ Human 1-chome, Showa-cho, Kariya city, Aichi Japan Denso Co., Ltd. (72) Inventor Yoshimasa Kodama 14 Iwatani Shimohakakucho, Nishio City, Aichi Prefecture Japan Auto Parts Research Institute, Inc.

Claims (1)

[Claims] 1. A deodorant obtained by adding a photocatalyst to the surface of an adsorbent layer on which an acidic gas adsorptive adhesive and a basic gas adsorptive adhesive are attached.