JPH06327922A - Air filter using zeolite - Google Patents

Abstract

PURPOSE:To provide the air filter having a filter effect equal to or more than the filter used to the air purifier and the air conditioner by using zeolite at least at a part of a structural element. CONSTITUTION:In the air filter for dust collection and deodorization used for an air purifier and an air conditioner, the zeolite is used at least at a part of a structural element. That is, the zeolite is porous, large in adsorptivity and has a catalytic action and an ion exchange property, etc. In such a way, the air filter having a filter effect equal to or more than the filter used for the air purifier and the air conditioner 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 filter using zeolite (zeolite) used in an air purifier or an air conditioner.

[0002]

2. Description of the Related Art Zeolites have been conventionally used in fields such as agriculture, fisheries, and animal husbandry. An example is as follows.

(1) Utilization in agriculture In Japan, natural zeolite has been used as a soil conditioner for a long time, and when it is applied to farmland, paddy rice, wheat, eggplant,
Increased yields of carrots, apples, etc. have been observed. This is because the pH of the soil can be adjusted by adding zeolite.
And the fertilizer components NH ⁺ and K ⁺ are selectively taken into the zeolite, so that the runoff of these is suppressed and the fertilizer retention is improved.

The ion-exchange action of zeolite is also C
It is said to prevent heavy metals such as u, Cd, Pb and Zn from transferring to plants. Zeolites are also used as pesticide carriers. This is because it has the effect of adsorbing agricultural chemicals having organic ions, preventing their runoff, and increasing their efficacy.

(2) Utilization in the fishery industry Zeolites are used in the fishery industry mainly for purifying water quality. When water is circulated and used for aquaculture, NH ₄ ⁺ is generated due to spoilage of excrement of leftovers and fish,
It is said that even if the concentration is several mg / l, it inhibits the growth of fish and makes the fish susceptible to diseases. This NH ₄ ⁺ can be easily removed with zeolite. Generally, a zeolite filtration tank is provided to circulate water, and
When it is saturated with H ₄ ⁺ , it is treated with about 3% saline or seawater and the filtration tank is reused. Zeolites are often used in eel farming in Japan. This is because it is considered that the amount of NH ₄ ⁺ generated will increase because eel heats water to raise the freeing density considerably.

(3) Utilization in livestock industry In Japan, it has been attempted to add zeolite to feeds for chickens, pigs and cattle since about 1965,
The added amount is 5 to 10% with respect to the feed, and it is said that the feed efficiency (body weight gain / ingested feed amount) is increased in any case. Further, it is known that zeolite has no side effects even when added to feed, and rather exhibits excellent efficacy. That is, in chickens and pigs, diseases such as stomach ulcer and pneumonia are reduced and the mortality rate is reduced. In addition, diarrhea stops, loose stools harden, and the odor of feces decreases.

Zeolite is also added to manure of livestock, and as a result, it is said that the generation of ammonia odor and maggot is reduced, the health of chickens is improved, and the production of eggs is increased.

[0008]

However, in the field of air filters for dust collection and deodorization used in air purifiers and air conditioners, techniques utilizing the excellent characteristics of zeolite have not yet been reported. Not not.

The present invention has been made in view of such conventional circumstances, and it is an object of the present invention to provide an air filter using zeolite having a filter function equal to or higher than that of an air filter used in an air cleaner. To aim.

[0010]

An air filter using zeolite provided by the present invention is an air filter for dust collection and deodorization used in an air cleaner or an air conditioner,
Zeolite (zeolite) is used for at least a part of the constituent elements.

[0011]

[Action]

(1) Since the zeolite of the present invention has the following various characteristics, it can be utilized for capturing harmful fine particles and bad odor in a gas such as air.

It is porous.

Zeolite is a water-containing aluminum / silicate crystal having a three-dimensional structure and has numerous pores of molecular size. That is, zeolite is a so-called "macromolecule" that belongs to an aluminosilicate-containing structure and is three-dimensionally linked with all of the oxygen atoms at the four vertices of the SiO ₄ tetrahedron being shared. For example, mordenite has a pipe shape, and its caliber is said to be 7 × 5.6 A elliptical.

In the ideal chemical composition, mordenite is N
_{a 8 Al 8 Si 40 O 96} · 24H 2 O, clinoptilolite, a _{Na 3 K 3 Al 6 Si 30} O 72 · 24H 2 O. However, since Na and K are ion-exchangeable, naturally occurring Na, K, Ca, and Mg are generally mixed. The ideal Si / Al ratio is 5, but natural zeolite generally does not have 5 because it contains other minerals as impurities.

The adsorptivity is high.

The pipe structure of natural zeolite is usually filled with water, but when heated at 400 to 600 ° C., it dehydrates and exhibits adsorptivity. It is known that this activated natural zeolite does not reach the synthetic zeolite in the adsorption capacity, but has the same water vapor adsorption strength as the synthetic zeolite and the second strongest adsorption strength after phosphorus pentoxide. Therefore, it is effective as a desiccant especially when low humidity is required. In addition to water, activated natural zeolite often adsorbs gas molecules having a dipole moment such as CO ₂ , NH ₃ , SO ₂ and H ₂ S. Although this also has an adsorption capacity inferior to that of synthetic zeolite, the adsorptivity is equivalent to that of synthetic zeolite.

Synthetic zeolite is currently used for the purpose of drying gas, liquid, desulfurization, decarboxylation, etc., but synthetic zeolite cannot be used in an acidic gas atmosphere or in an acidic solution because the crystal structure is easily destroyed. . Natural zeolites, on the other hand, are superior to synthetic zeolites for such applications because of their high acid resistance.

It has a catalytic action.

When the zeolite is heated and activated, it functions as a solid acid catalyst in addition to the gas adsorption function. At present, the most noticeable property of zeolite is this catalytic action, and MTG (methanol to Gasol) is used.
ine) is utilized in Cl chemistry centering on the reaction. Most of the zeolites used in such applications are synthetic zeolites, and natural zeolites are rarely used. This seems to be because natural zeolite is inferior to synthetic zeolite in uniformity of pore size, and because it contains impurities, its adsorption capacity is also low.

However, the Shimane Prefectural Industrial Technology Center has succeeded in refining natural zeolite having gas adsorption, action and catalytic action to a high-purity zeolite with an average particle size of 20μ and around 92%. Therefore, the above purified zeolite can be used in the fields of gas adsorption and catalysts. In some cases, natural zeolite is used as a catalyst for deodorizing factory exhaust gas.

Ion Exchangeability Zeolites have the highest cation exchange capacity among naturally occurring minerals. The quality zeolite produced in Japan is generally 120-180 meq / 100g.
Has a CEC value of. The priority of the ion exchange is as follows.

Cs ⁺ > Rb ⁺ > K ⁺ > NH ₄ ⁺ > Ba ²⁺ >
Sr ²⁺ > Na ⁺ > Ca ²⁺ > Mg ²⁺ > Li ⁺ Due to these characteristics, NH ₄ ^{+ in} gas and Cs ⁺ , NH ₄ ⁺ , K ⁺ in aqueous solution are selectively ionized. It is possible to exchange and adsorb.

(2) It is considered that harmful fine particles and malodor in the gas are captured by the synergistic action of the above characteristics.
Specifically, for example, the following can be considered.

Zeolite is not only highly adsorptive but also has numerous pores of molecular size, so that gas molecules such as CO ₂ , NH ₃ , SO ₂ and H ₂ S in the gas can be converted into zeolite. It is effectively absorbed. In addition, dust such as bacteria, viruses, house mite feces, mold spores, and pollen floating in the air are also adsorbed.

Zeolite not only has a catalytic action, but also has an innumerable number of pores of a molecular size.
_{Acts as} an oxidation catalyst for _x . Further, since it has an ion exchange property, NH ₄ ⁺ in the gas is selectively ion-exchanged and adsorbed. Therefore, the bad odor caused by NO _x NH ₄ ⁺ or the like is removed.

[0026]

[Example] An air filter to be used in the following electronic air cleaner (manufactured by Kankyo Co., Ltd., product name "Clearvale") was prepared in the following manner, and the air filter was installed in the above cleaner and the test space The dust collecting effect and the deodorizing effect in the (room) were evaluated according to the following test procedure.

As a comparative example, the effect of using a conventional dust-collecting paper (nonwoven paper) was also evaluated in the same manner as in the example.

Table 2 shows the respective evaluation results.

(1) Specifications of electronic air purifier and dust collection principle Specifications (trade name: Clearvale) Required power 4W Discharge voltage + 8,000V, -8,000V Power supply voltage 100V (single phase 100V, 50 /
60 Hz) Rated current (primary side) 40 mA Step-up method Multi-stage pressure doubler method Dust collection principle It will be described with reference to FIGS.

I. Ionization line 1 is minus 8,000
Since a high voltage of plus 8,000 V is applied to V and the dust collecting plate 2, corona discharge occurs during this period. In addition,
Reference numeral 4 is a substrate, and 5 is a room, which corresponds to a test space described later (FIG. 1A).

II. Due to this discharge, a large amount of electrons fly out from the ionization line 1 toward the dust collecting plate 2 at an extremely high speed and are diffused in the air (FIG. 1 (b)).

III. As a result, the molecules of air in the room (particularly oxygen molecules) become a state of having extra electrons, that is, negative ions (FIG. 1C).

IV. Dust floating in the air, such as bacteria, vislu, house mite feces, mold spores, and pollen, receives negative static electricity by receiving electrons from negative ions. (FIG. 1 (d)).

V. The negatively charged dust is attracted to the positively charged dust collecting plate 2 by the Coulomb force and adheres to the air filter 3 (FIG. 1 (d)).

VI. Further, a part of the negatively ionized oxygen molecules is attracted to the dust collecting plate 2, but most of the negative ions remain as negative ions, filling the room with negative ions (FIG. 1D).

(2) Preparation of air filter In this example, the following first air filter and second air filter were prepared.

[0037] The exposed skin of the first air filter Mitsumata (Sanmaki) was steamed under normal pressure with an aqueous solution of caustic soda, and the pulp obtained was washed with water and beaten with a wooden hammer to add an aqueous solution of polyethylene oxide (mucus) to it. 80 parts by weight of 100 parts by weight of pulp, an average particle size of 20μ, and a purified zeolite having a purity of 90% are used in pulp 10.
80 parts by weight to 0 parts by weight, respectively added and mixed,
After a while, I plowed it to a thickness of 3 mm using a plow.

The zeolite-mixed paper obtained was dried at 50 ° C. for 2 hours and used as an air filter in the examples.

Second air filter Purified zeolite having an average particle size of 20μ and a purity of 90% is molded to have mesh pores, length 290 mm, width 390 mm,
A perforated plate having a thickness of 2 mm was used as the air filter of the example.

(3) Test space (room) Size 10-room Western-style room with a ceiling height of 2,400 mm Environment inside the space, left unused for one year (4) Test method In the above-mentioned sealed room Three of the above electronic air purifiers (Clearvale) were installed, two of which were equipped with the first
Then, the second air filter was installed, and the dust collecting paper of the comparative example was installed on the other one, and the three were operated simultaneously for one hour.

(5) Evaluation method The size of the dust per 1 cm ² of the first and second air filters and the dust collecting paper after use were evaluated according to the following criteria.

Medium: around 5μ Small: 1μ or less The collection efficiency (%) was measured by the method of Table 1 according to the classification of dust.

[0043]

[Table 1]

The presence or absence of bacteria was determined by pressing 1 cm ² pieces of the first and second air filters and dust collecting paper against an agar medium of a petri dish, placing the petri dish in an incubator, and culturing at 37 ° C. for 24 hours. It was judged.

[0045]

[Table 2]

The odor of the room, especially the musty odor, was considerably reduced.

As is clear from Table 2, it was found that the air filters of Examples had at least a dust collecting effect and a deodorizing effect equivalent to those of the conventional dust collecting paper.

[0048]

As described above, since the air filter of the present invention is constructed so that at least a part thereof is made of zeolite, it is possible to exhibit a filter effect equal to or higher than that of the conventional air filter.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a dust collecting principle of an electronic air cleaner used in an embodiment.

[Explanation of symbols]

 1 Ionization line 2 Dust collector 3 Air filter 4 Substrate 5 Room

Claims (1)

[Claims] 1. An air filter for dust collection and deodorization used in an air purifier or an air conditioner, wherein zeolite (zeolite) is used as at least a part of constituent elements, and zeolite is used. Air filter.