JP2989677B2 - Molded adsorbent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded adsorbent useful for adsorbing water and the like.

[0002]

2. Description of the Related Art To remove chlorine odor and the like in tap water,
BACKGROUND ART Water purifiers for home use and business use are equipped with a molded adsorbent having a papermaking structure in which activated carbon fibers are bonded with a binder. This molded adsorbent has high adsorption speed, adsorption ability and water permeability to chlorine components and the like. However, since the molded adsorbent has no bactericidal action, there is a possibility that microorganisms such as Escherichia coli will propagate.

On the other hand, silver ions are known as substances having a bactericidal action. By impregnating the silver ions with the granular activated carbon, activated carbon having a bactericidal action is obtained. However, the pores of activated carbon fibers, compared to granular activated carbon,
Due to its small diameter, silver ions cannot be impregnated. That is, even if silver ions are impregnated on the surface of the activated carbon fiber, the silver ions do not enter the micropores of the activated carbon fiber. Therefore, when treated water is passed, the silver ions flow out, and the sterilizing action cannot be maintained.

[0004]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a molded adsorbent having high adsorptive capacity and sterilizing action despite using activated carbon fibers as an adsorbent.

[0005]

In order to achieve the above object, the present invention provides a molded adsorbent comprising activated carbon fibers, silver-impregnated activated carbon or silver-impregnated zeolite, and a fibrous binder.

Activated carbon fibers can be obtained, for example, by activating carbon fibers such as polyacrylonitrile, phenolic resin, cellulose, rayon, and pitch.
The specific surface area of the activated carbon fiber is, for example, 500 to 2500.
m ² / g, and is characterized by a high adsorption rate and a high adsorption capacity due to its unique micropore structure. The activated carbon fibers may be used in combination with powdered or granular activated carbon.

[0007] The silver-impregnated activated carbon and the silver-impregnated zeolite are obtained by supporting silver on granular activated carbon or zeolite as a porous carrier. As the granular activated carbon, those having a specific surface area of, for example, about 500 to 1500 m ² / g can be used. The amount of silver added is, for example, about 0.01 to 10% by weight, preferably about 1 to 7.5% by weight, and more preferably about 3 to 6% by weight. When the attached amount of silver is less than 0.01% by weight, the bactericidal action is small, and when it exceeds 10% by weight, silver is easily eluted. The silver-impregnated activated carbon and the silver-impregnated zeolite can be used alone or in combination.

[0008] The fibrous binder joins the activated carbon fiber and the silver-impregnated activated carbon and / or the silver-impregnated zeolite to be integrated. Examples of the fibrous binder, for example, pulp; include etc. thermoadhesive textiles. The heat-adhesive fibers include, for example, olefin fibers such as polyethylene and polypropylene, polyester fibers, acrylic fibers, polyacrylonitrile fibers, and composite fibers. The fibrous binder is made of activated carbon fiber micropores.
Blockage can be suppressed and suction moldability is excellent. Particularly preferred ba
The inders are pulp and / or heat bonding fibers. This
One or more of these binders can be used. Fiber
Fiber binder is a thermo-adhesive resin binder , for example,
Conventional thermoplastic polymers such as olefin polymers such as polyethylene and polypropylene, polyvinyl acetate, polyvinyl alcohol, polyester, nylon, acrylic resin, polyacrylonitrile, and styrene polymers
You may use together. The form of the thermo-adhesive resin binder is
It can be selected according to the manufacturing method of the adsorbent, such as liquid or powder
Any of these may be used.

[0009] In addition to the above components, the molded adsorbent may contain non-thermo-adhesive reinforcing fibers. As a reinforcing fiber,
Examples thereof include natural fibers such as cotton and hemp; synthetic fibers such as aromatic polyamide fibers and aromatic polyester fibers; semi-synthetic fibers such as rayon; and inorganic fibers such as glass fibers, carbon fibers, alumina fibers, and metal fibers. . One or more of these reinforcing fibers can be used. In order to reinforce the molded adsorbent, synthetic fibers and inorganic fibers having high mechanical strength are preferred.

The ratio between the activated carbon fiber and the silver-impregnated activated carbon and / or the silver-impregnated zeolite can be selected within a range that does not impair the adsorptivity and sterilization property. For example, activated carbon fiber / silver-impregnated activated carbon and silver-impregnated zeolite = 10-90 / 90-1
0, preferably about 25 to 75/75 to 25 (weight ratio). The total amount of the activated carbon fiber, the silver-impregnated activated carbon and the silver-impregnated zeolite is, for example, 50 to 99% by weight, preferably 75 to 99% by weight, more preferably 9 to 99% by weight in the molded adsorbent.
It is about 0 to 99% by weight, particularly preferably about 95 to 98% by weight.

The content of the fibrous binder can be selected within a range that does not impair the integrity and processing efficiency of the molded adsorbent, and is, for example, 1 to 50% by weight, preferably 1 to 25% by weight, more preferably It is about 1 to 10% by weight, especially about 2 to 5% by weight.

The adsorbent has a dispersing agent, a stabilizer, a viscosity modifier, an anti-settling agent, a thickener, a filler, a paper-strengthening agent, and a coagulating action as long as the adsorbing ability and strength are not adversely affected. Surfactants, in particular, various additives such as a polymer flocculant and a retention aid may be contained.

[0013] Since such a molded adsorbent combines the activated carbon fiber with the silver-impregnated activated carbon and / or the silver-impregnated zeolite, it mainly has a high adsorptivity of the activated carbon fiber, the silver-impregnated activated carbon and the silver-impregnated activated carbon. Both functions of zeolite exhibiting a high bactericidal action are exhibited. Therefore, when treating tap water, chlorine components, odor components, moldy odor, and the like can be removed while preventing the growth of microorganisms such as Escherichia coli in the fluid to be treated.
Therefore, the treated water is sanitary. Furthermore, since the fluid to be treated is turbulent by the silver-impregnated activated carbon and the silver-impregnated zeolite, when the fluid to be treated is treated by the molded adsorbent, the process of treating the fluid to be treated becomes longer and the treatment efficiency can be increased. In particular, since a fibrous binder such as pulp and / or heat-adhesive fiber is used as the binder , the content of activated carbon fibers and activated carbon impregnated with silver can be increased, and the micropores of the activated carbon fibers can be prevented from being clogged.
Since the flow path is further complicated, the processing efficiency can be further improved.

The shape of the molded adsorbent can be appropriately determined according to the intended use, and may be, for example, a sheet or a hollow cylinder. Further, the sheet-shaped molded adsorbent may be embossed or processed into a honeycomb structure.

As described above, when a molded adsorbent is prepared using a binder, active sites such as micropores of activated carbon fibers and activated carbon impregnated with silver are easily blocked. Therefore, it is generally difficult to form a composite of activated carbon fiber and activated carbon impregnated with silver while maintaining a high adsorption capacity and a bactericidal action. The molded adsorbent of the present invention having a high adsorption ability and a bactericidal action can be produced, for example, by the following method.

(1) A suction molding method in which a slurry containing the above components is sucked by a suction mold, and the components are deposited on the suction mold, or the slurry is injected into the suction mold and sucked.

[0017]

(2) A method of injecting a slurry containing the above-described components into a hygroscopic mold such as gypsum, absorbing the water in the slurry into the mold, and molding.

In the above-mentioned (1) suction molding method, a molded adsorbent can be obtained by heating and drying a molded product removed from a suction molding die. In this suction molding method, molded articles of various shapes corresponding to the inner surface or outer surface shape of the mold can be obtained . In the method (2) in is al, there is no leakage of components in the slurry be used fine granular material, such as silver-impregnated activated carbon and silver impregnated zeolite, the content of silver-impregnated activated carbon and silver impregnated zeolite Can be enhanced.

In preparing the slurry, it is preferable to beat activated carbon fibers and the like. The solid content concentration in the slurry is, for example, about 0.1 to 2 % by weight in the method (1 ), and is, for example, 5 to 5% in the method (2).
It is about 0% by weight. When the binder has thermal adhesiveness, the binder is bonded to the granular activated carbon and / or the reinforcing fibers by heating and drying. The heating and drying of the wet molded adsorbent can be performed, for example, at a temperature of about 100 to 200 ° C.

The molded adsorbent thus obtained has a papermaking structure excellent in water permeability and air permeability. Therefore,
Low pressure loss during adsorption treatment and high adsorption capacity.

The molded adsorbent of the present invention can be used for various processes such as removal of chlorine components and the like in water, sterilization of microorganisms in water and deodorization and decolorization of liquid.

[0023]

The molded adsorbent of the present invention has a high adsorption capacity and a bactericidal action, and has a high treatment efficiency.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to embodiments.

EXAMPLE A silver-impregnated activated carbon (trade name: silver coated Shirasagi, trade name, manufactured by Takeda Pharmaceutical Co., Ltd.), 8 parts by weight, cut into chops with a fiber length of 1 to 3 mm, a pitch-based activity having a nominal specific surface area of 1500 m ² / g 87 parts by weight of carbon fiber (trade name: A-15, manufactured by Ador Co., Ltd.) and 5 parts by weight of polyacrylonitrile fiber as a binder cut to a fiber length of 1 to 3 mm were added to 2,000 parts by weight of water and stirred in a water tank. A uniform slurry was prepared.

Then, a suction mold having an inner diameter of 30 mmφ and a depth of 30 mm, having a number of small holes formed in the bottom plate and having a suction portion formed therein is immersed in a slurry tank and subjected to suction molding. It was taken out and dried at 140 ° C. for 2 hours to obtain a molded adsorbent.

The size of the obtained adsorbent is 30 mm in diameter,
It had a cylindrical shape with a height of 30 mm, weighed 3.2 g, and had a specific surface area of 1380 m ² / g.

Next, sample water having an E. coli concentration of 60 cells / ml was supplied to the molded adsorbent at a flow rate of 1 ml / min using a pump. Then, a predetermined amount of effluent water is collected at predetermined time intervals, dropped onto an agar medium kept at a temperature of 50 ° C., solidified in a plate shape, and then placed in a 37 ° C. incubator at a temperature of 37 ° C.
After culturing for one day, the number of viable bacteria was determined from the number of colonies, and the bactericidal efficiency was evaluated. As a result, the amount of E. coli in the running water after supplying the sample water for 50 hours was 5,400 CFU / ml.

Comparative Example A molded adsorbent was obtained in the same manner as in the example except that 95 parts by weight of the activated carbon fiber of the example were used without using the silver-impregnated activated carbon.

The weight of the obtained adsorbent was 2.9 g, and its specific surface area was 1460 m ² / g. Then, when the number of viable cells was determined from the number of colonies in the same manner as in the example, after supplying the sample water for 50 hours, the amount of E. coli in the running water was 548.
It was 00 CFU / ml.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-278408 (JP, A) JP-A-57-132585 (JP, A) JP-A-4-210286 (JP, A) JP-A-4-210 94791 (JP, A) Japanese Utility Model Showa 64-39897 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B01J 20/20 A61L 2/16 C02F 1/28 C02F 1/50 531

Claims (1)

(57) [Claims] 1. A molded adsorbent comprising activated carbon fibers, silver-impregnated activated carbon or silver-impregnated zeolite, and a fibrous binder.