JP3131480B2 - Air purifier and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an air purifier and a method for producing the same. More specifically, the present invention relates to a high-performance air purifying agent capable of effectively purifying environmentally contaminated air contaminated at a very low concentration and a method for producing the same.

[0002]

2. Description of the Related Art In the present situation where purification of the global environment has become a major problem, the control and prevention of air pollution has become an urgent issue. There is a strong demand for air purification for pollution.

Conventionally, as a means for purifying air, a dry method and a wet method are known, but a dry purification method using activated carbon has been used for a long time from the viewpoint of simplicity. In addition, various air purifying agents that exhibit selective adsorption ability according to the type of contaminated gas have been developed.For example, for removal of an acidic gas or a basic gas, a base or acid agent is applied to a porous carrier. What is carried is considered to be effective. In particular, an air purifying agent having an oxidizing agent or a reducing agent supported on a carrier has a purifying ability to decompose pollutant gas by strong oxidizing / reducing power, and is therefore widely used in the industry.

Examples of this type of air purifying agent include those in which potassium permanganate is supported on a carrier such as activated alumina or zeolite (JP-A-60-827, JP-A-1-157175, etc.) and activated carbon. Having iodate and / or inorganic acid supported thereon (Japanese Patent Application Laid-Open Nos. 61-68136 and 62-16
No. 1372, JP-A-62-161373).

[0005] These air purifying agents have been put to practical use according to the purpose of use, but each has its own merits and demerits, and there are problems in that its use is limited due to its inherent physical properties. For example, potassium permanganate-based air purifying agents are soluble and powerful oxidizing agents, so care must be taken when handling them. In the field of can not be used. Activated carbon has high safety during use, but the removal mechanism is mainly based on physical adsorption, so not only the removal rate of pollutant gas is naturally suppressed, but also when saturated, there is no adsorption action and even the desorption phenomenon Will occur. Therefore, in many cases, the drug is used in a state in which the drug is supported, but the ability to remove low-concentration pollutant gas and the service life cannot be expected much.

[0006]

Recently, it is possible to improve the product accuracy and yield in the field of manufacturing precision electronics such as semiconductors, or prevent permanent discoloration of high-grade works such as paintings. Therefore, there is a strong demand for the development of an air purifying agent capable of completely and safely removing extremely low-concentration pollutant gases.

The present invention has been developed as a result of intensive studies in view of such demands, and has as its object the purpose of providing air that is safe, has a long service life, and has a sufficient ability to remove low-concentration pollutant gases. It is an object of the present invention to provide a purifying agent and a production method for industrially obtaining the air purifying agent.

[0008]

Means for Solving the Problems An air purifying agent according to the present invention for achieving the above object is characterized in that a carbon material carrier has activated manganese dioxide and iodate supported thereon. It is.

The carbon material carrier used in the present invention includes:
Activated carbon, graphite, carbon black and the like can be mentioned, but it is particularly preferable to use activated carbon. Regardless of the type and production history of the activated carbon, for example, wood, coconut husk, sawdust, coal, lignite, lignite, bamboo charcoal, or the like obtained by activating them can be used. The shape is arbitrary, and powder, granule, fiber, honeycomb, etc. may be appropriately selected according to the purpose of use.

As the active manganese dioxide to be supported on the carbon material carrier, either a reduction decomposition product of potassium permanganate or an oxidative decomposition product of manganese hydroxide is used, but from the viewpoint of performance and production. Preference is given to using the decomposition products of potassium permanganate. The activated manganese dioxide may contain a small amount of fine particles of a metal or a metal compound such as copper, vanadium, silver, palladium, and platinum as needed.

As the iodate as the other agent to be supported on the carbon material carrier, potassium iodate is preferable, but other alkali metal salts such as sodium iodate and lithium iodate, calcium iodate and magnesium iodate And alkaline earth metal salts such as barium iodate.

The amount of active manganese dioxide and iodate supported on the carbon material carrier should be arbitrarily set depending on the use of the carbon purifying material and the properties of the pollutant gas. 0.1-20wt per weight
%, Preferably in the range of 0.3 to 10% by weight. The ratio between active manganese dioxide (in terms of MnO ₂ ) and iodate is 1: 0.1 to 9, preferably 1: 0.5 to 5, by weight.

Further, the air purifying agent of the present invention can contain water in excess of equilibrium water as long as it does not solidify or deteriorate during storage, transportation or handling.
It is preferable to contain about% of water. The moisture in this case refers to the total weight loss component when the air purifying agent is dried at 100 ° C. for 1 hour, and the amount refers to the ratio to the air purifying agent.

The air purifying agent according to the present invention can be formed in various forms according to the shape of the carrier. However, in the case of a shape other than the honeycomb body, the air purifying agent has a pore volume of 0.5 by the carbon tetrachloride substitution method. ~ 1.0ml / g, preferably 0.6 ~ 0.9ml / g
Those in the range exhibit good air purifying ability.

The production method according to the present invention for obtaining the above-mentioned air purifying agent is characterized in that the carbon material carrier is adsorbed and loaded with a mixed aqueous solution of potassium permanganate and iodate.

The mixed aqueous solution of potassium permanganate and iodate exists stably without causing substantial oxidation-reduction reaction, but when mixed with a carbon material carrier, only potassium permanganate rapidly reduces the reaction. To convert to activated manganese dioxide. Such conversion phenomenon, MnO ₄ in After contacting the carbon material carrier and drug mixture ^- can be demonstrated from the fact that the red-violet color reaction is not substantially observed.

On the other hand, iodate can be made to exist more stably by the insoluble oxidizing agent of active manganese dioxide than when it is used alone. This action stabilizes the air purifying agent obtained and removes pollutant gas. Noh will be excellent in the long term.

The process of adsorbing and supporting the mixed solution of the drug on the carbon agent carrier is not particularly limited as long as the drug can be uniformly loaded, but it is practical to perform the mixing by direct mixing or spray mixing with an appropriate mixer. It is. For example, by uniformly spraying a drug mixture while mixing a carbon material carrier in a mixer, the carrier can be uniformly supported. In this case, the concentration and the mixing ratio of the mixed liquid may be set within the range of the amount of the agent carried on the air purifying agent or the amount of water. Therefore, if the drug mixture is prepared within the range of the water content in the air purifying agent, it can be provided as a product without any special post-treatment after the mixing process of the carbon material carrier and the drug. Further, when excessive water is used or when a high molding strength is desired, a drying treatment can be performed as necessary. When carrying the drug on the carbon material carrier, an auxiliary component such as an acid, an alkali, or a suitable binder may be used in combination, if necessary.

The air purifier according to the present invention can effectively remove single or multiple pollutant gases of various harmful gases. For example, hydrogenated gas such as hydrogen sulfide, phosphine, arsine, germane, silane, ozone, C
O, NO _x , SO _x , amines, mercaptans, carbonyl sulfide, aldehydes, phenols, unsaturated hydrocarbons such as ethylene, or sewage odor, animal odor, human urine odor, etc., which are contaminated by these components. The odor is efficiently removed. Further, the air purifying agent of the present invention also has a bactericidal property due to strong oxidizing power, and in particular, those having copper or silver supported thereon have a higher antibacterial activity, so that various bacteria in the air, mold, virus, etc. Harmful microorganisms can also be removed at the same time.

[0020]

The air purifying agent according to the present invention is constituted by carrying insoluble active manganese dioxide and a soluble iodate as effective components on a carbon material carrier as described above. The adsorptive capacity, the reducing power and the two different strong oxidizing powers interact to efficiently decompose or adsorb harmful pollutant gases. Through this function, strong removal ability is effectively maintained for a long period of time. Also, the removal spectrum contaminant concentration for harmful gases has a very wide range, and the safety during use is high.

[0021]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples and comparative examples.

Examples 1 to 4 and Comparative Examples 1 to 3 A mixed drug solution obtained by dissolving a predetermined amount of potassium permanganate and potassium iodate in 100 parts by weight of water is flown by a Nauter mixer to a particle diameter of 3 to 5 mm. Sprayed and supported on granular coconut shell activated carbon to prepare air purifiers of Samples B to E (Examples 1 to 4). Further, Sample A not supporting either or both of potassium permanganate and potassium iodate,
F and G air purifiers were produced (Comparative Examples 1 to 3).

[0023] Of these the air purification agent, was a sample A~E is immersed in water, MnO ₄ ^- coloration red purple is not substantially observed, and converted to an active insoluble manganese dioxide It was found to be carried.

Each of the obtained air purifying agents of Samples A to G is packed in a column (25 mm in inner diameter, 350 mm in length) of a Pyrex tube,
The hydrogen sulfide removal ability was evaluated under the following conditions. Inlet gas concentration: approx. 10 ppm H ₂ S Inlet gas temperature, humidity: 22 to 25 ° C., 55 to 65% RH gas flow rate, flow velocity in pipe: 10.3 l / min, 0.35 m / sec Space velocity (SV): 20000 (1 / H) Measurement method: Gastec detection tube method (detection limit 0.1 ppm H
₂ S) The results are shown in Table 1 in comparison with the composition of the air purifying agent and the pore volume.

[0025]

[Table 1]

Examples 5 to 6, Comparative Example 4 60 parts by weight of activated alumina, 10 parts by weight of bentonite, 10 parts by weight of sepiolite, 5 parts by weight of potassium permanganate, 10 parts by weight of slaked lime and silica sol (SiO ₂ : 30% by weight) 21 A sample H is kneaded with an appropriate amount of water, granulated, and dried.
Potassium permanganate-based air purifier (3kg / grain strength)
(Grain, pore volume: 0.52 ml / g) (Comparative Example 4).

Using the sample H, the sample B of Example 1, and the sample D of Example 3, a long-term removal test (240 to 10,000 hours) of a rare H ₂ S gas was performed under the following conditions. The results in Table 3 were obtained. Inlet gas concentration: about 500 ppb H ₂ S Inlet gas temperature: 22 to 25 ° C Inlet gas humidity: 60 to 70% RH Space velocity (SV): 5000 (1 / H) Measurement method: gas chromatography

[0028]

[Table 2]

[0029]

[Table 3]

Example 7 and Comparative Example 5 Using the sample D of Example 3 and the sample H of Comparative Example 4, a SO ₂ gas removal test was performed under the following conditions, and the results shown in Table 4 were obtained. Inlet gas concentration: about 200 to 300 [ppb SO ₂ inlet gas temperature: 22-25 ° C. inlet gas humidity: 55 to 65% RH Gas Wind: 20 l / min space velocity (SV): 50000 (1 / H) Column: inner diameter 25mm, length 350mm (Pyrex tube) Measuring method: Gas chromatography

[0031]

[Table 4]

Example 8 and Comparative Example 6 Using the sample D of Example 3 and the sample H of Comparative Example 4, the ability to remove a hydrogen sulfide-toluene mixed gas was tested under the following conditions. The result was obtained. In addition, it shows that ND was not detected in the table. Inlet gas concentration: about 20 ppm H ₂ S + about 50 ppm Toluene mixed gas Inlet gas temperature: 23 to 25 ° C Inlet gas humidity: 60 to 70% RH Gas flow rate: 10 l / min Space velocity (SV): 50,000 (1 / H) Column: Inner diameter 25mm, length 350mm Measurement method: Gastec detector tube method (4LL) (122) Toluene uses a standard gas generator (permeator)

[0033]

[Table 5]

[0034]

[Table 6]

Example 9 and Comparative Example 7 Using Sample D of Example 3 and Sample H of Comparative Example 4, a removal test of digested sludge odor (odor concentration) in a sewage treatment plant was performed under the following conditions. 7 results were obtained. Inlet odor concentration: about 1000 Inlet gas temperature: 20 to 27 ° C Inlet gas humidity: 60 to 70% RH Gas flow rate: 10 l / min Space velocity (SV): 20000 (1 / H) Column: Inner diameter 25 mm, length 350 mm Measuring method: Three-point comparison odor bag method When odor concentration is 10 or less, odor is hardly felt

[0036]

[Table 7]

Example 10, Comparative Examples 8 to 10 Using Sample D of Example 3, Sample F of Comparative Example 2, Sample H of Comparative Example 4, and Sample I (commercial product: manganese ferrite air purifying agent), Ethyl mercaptan (C ₂
When a test for removing H ₅ SH) was performed, the results shown in Table 8 were obtained. Inlet gas concentration: 100 to 140 ppm C ₂ H ₅ SH Inlet gas temperature: 23 to 26 ° C Inlet gas humidity: 73 to 83% RH Space velocity (SV): 5000 (1 / H) Gas flow rate: 4 l / min Measurement method ： Gastec detector tube No.72, Odor test

[0038]

[Table 8]

Example 11 and Comparative Examples 11 to 14 Activated carbon honeycomb having a mesh size of 1 mm was cut with a diamond cutter.
Cut into 22 mm x 22 mm x 9 mm thickness, 4 parts by weight of potassium permanganate and 5 parts by weight of potassium iodate per 1000 parts by weight
After immersing in an aqueous solution in which parts by weight were dissolved at a temperature of 45 ° C. for 30 minutes, it was dried to obtain an air purifier having a water content of 9.5% by weight (sample J). Even if the sample J was leached in water, MnO
₄ ^- since the coloration was observed in was found to be holding and converted into activated manganese dioxide.

For comparison, an air purifying agent (sample K) in which 4% by weight of potassium permanganate was supported on an activated alumina honeycomb having a mesh size of 1 mm, and 1% on the same activated alumina honeycomb
An air purifying agent (sample L) supporting potassium iodate by weight%, an air purifying agent supporting potassium permanganate at 3 wt% on zeolite honeycomb (sample M), and an air purifying agent comprising activated carbon honeycomb (sample L) Sample N) was prepared.

Using each of these air purifying agents, the ability to remove SO ₂ gas was tested under the following conditions, and the results shown in Table 9 were obtained. Inlet gas concentration: 585 ppm SO ₂ Inlet gas temperature: room temperature Inlet gas humidity: 50-60% RH Space velocity (SV): 25000 (1 / H) Measuring method: Gastec detector tube

[0042]

[Table 9]

[0043]

As described above, according to the present invention, there is provided an air purifying agent which exhibits excellent ability to remove low-concentration pollutant gas over a long period of time, and a production method capable of industrially producing this air purifying agent. can do. The air purifying agent of the present invention has a K
MnO soluble MnO like _{4 4} ^- more secure because there is no, it is very useful for wide application purposes ranging from industrial for general consumer use.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-288545 (JP, A) JP-A-53-87980 (JP, A) JP-A-2-139035 (JP, A) JP-A 61-87 293547 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01J 20/00-20/34

Claims (4)

(57) [Claims] 1. An air purifying agent comprising an active manganese dioxide and an iodate supported on a carbon material carrier. 2. The air purifying agent according to claim 1, wherein the active manganese dioxide is a decomposition product of potassium permanganate, and the iodate is potassium iodate. 3. The air purifying agent according to claim 1, wherein the pore volume is in a range of 0.5 to 1.0 ml / g. 4. A method for producing an air purifier comprising adsorbing and supporting a mixed aqueous solution of potassium permanganate and iodate on a carbon material carrier.