JPH0538415A - Filter for decomposing ozone - Google Patents

Abstract

PURPOSE:To provide a filter for decomposing ozone having a lower pressure loss, a high decomposition capacity, and a long life. CONSTITUTION:A cured product of a composition comprising 100 pts.wt. of a resol-type phenolic resin (a), 1-100 pts.wt. of a lipophilic compound (b) which is liquid at room temperature and has a boiling point of 100 deg.C or higher, and 1-100 pts.wt. of a hydrophilic liquid compound (c) having a boiling point of 100 deg.C or higher is carbonized and activated to obtain a porous structure of activated carbon. The structures are allocated in the air passage of a filter for decomposing ozone.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter used for ozone decomposition and the like.

[0002]

2. Description of the Related Art Ozone is used for a wide range of purposes such as water purification, deodorization, and bleaching by utilizing its oxidizing power. However, ozone itself is harmful to the human body, and the working environment concentration is regulated to 0.06 ppm or less. Furthermore, recently, with the spread of office machines such as copiers that use high-voltage discharge, the destruction of the work environment by ozone generated from these devices has become a problem, and a filter for decomposing ozone is installed. ing.

Various types of filters for ozone decomposition have hitherto been proposed. For example, JP-A-57-
As described in Japanese Patent No. 177329, activated carbon has also been used as a simple and economical material for a long time. However, the use of granular or powdery activated carbon as a filter material for office machines has a problem in terms of working environment such as dust. Therefore, the use of a honeycomb-like activated carbon structure filter for ozone decomposition is disclosed in, for example, JP-A-60-908.
It is already known as described in Japanese Patent Publication No. 03, etc. An ozone decomposing activated carbon filter provided in an office machine such as a copying machine is required to have a low pressure loss and a high decomposition performance because the capacity of a blower provided in the equipment is limited.

It is known that the activated carbon used for the ozonolysis filter is also consumed at a certain rate as the ozonolysis proceeds. Therefore, it is considered that the service life of this ozone decomposition filter depends on the total weight of the activated carbon constituting the filter. Further, it is considered that the pressure loss of the ozone decomposing filter depends on the size of the resistance of the filter when the gas flow passes through the filter, in other words, the size of the passage, that is, the aperture ratio.

The ozone decomposing activated carbon filter provided in an office machine such as a copying machine is required to have a low pressure loss and a high decomposition performance because the capacity of the blower provided in the machine is limited. Of course, a long life is advantageous for maintenance inspection. Therefore, many attempts have been made so far to obtain a filter having a long life and a low pressure loss, but a satisfactory filter for ozone decomposition has not been obtained yet.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention has reached the present invention as a result of extensive studies on a filter for ozone decomposition which has lower pressure loss and high deodorizing performance and has a longer life.

[0007]

Means for Solving the Problems That is, the present invention is based on 100 parts by weight of a resol type phenolic resin (a) and 10 parts by lipophilicity.
A cured product of a composition comprising 1 to 100 parts by weight of a liquid compound (b) having a boiling point of 0 ° C. or higher at room temperature and 1 to 100 parts by weight of a hydrophilic liquid compound (c) having a boiling point of 100 ° C. or higher. The filter for ozone decomposition is characterized in that the activated carbon porous material structure obtained by carbonizing and activating is disposed in an air passage.

The present invention will be described in more detail. The resol type phenolic resin (a) used in the present invention means, for example, 1 mol of phenol and 1 to 3 mol of formalin as an alkaline catalyst such as NaOH, KOH, Ca (OH) 2, Ba.
In the presence of (OH) 2, NH2 (CH2CH3), etc.
It is a liquid having a viscosity at room temperature of 1000 to 20000 cps, which is obtained by condensing by heating at 100 ° C. and then distilling off water under reduced pressure until the solid content becomes 60 to 80%.

In the present invention, the lipophilic compound having a boiling point of 100 ° C. or higher and being liquid at room temperature is, for example, a straight-chain compound such as octane, nonane, decane, undecane, dodecane, kerosene, mineral oil, liquid paraffin, or the like. Examples thereof include branched alkyl compounds and cyclic alkylene compounds such as toluene and xylene. Among these, liquid paraffin is preferable because it has a viscosity similar to that of resole and a stable oil-in-water dispersion system can be prepared when mixed.

The lipophilic compound (b) is usually added in an amount of 1 to 1 with respect to 100 parts by weight of the resol type phenol resin (a).
00 parts by weight, preferably 10 to 60 parts by weight. If the amount of the lipophilic compound (b) is too small, the porous structure of the activated carbon porous body will be small, resulting in poor adsorption performance and liquid impregnation property. In addition, explosion occurs during carbonization and activation, making it difficult to produce activated carbon. On the other hand, when the amount exceeds the above range, the curing property of the resole becomes poor. In addition, the shrinkage of the cured product is large during carbonization, and cracking is likely to occur.

The liquid compound (c) having a boiling point of 100 ° C. or higher in the present invention means, for example, an oxyalkylene compound having a degree of polymerization of 2 or higher, for example, diethylene glycol, triethylene glycol, polyethylene glycol having a molecular weight of less than 1000. , Dipropylene glycol,
Examples thereof include polypropylene glycol having a molecular weight of less than 1000, glycerin and the like. Among these, polyethylene glycol having a molecular weight of 400 to 600 or dipropylene glycol is preferable because it is relatively close to the viscosity of the resole and has a suitable compatibility.

Resol type phenolic resin (a) 10 of this liquid compound (c) having a boiling point of 100 ° C. or higher
The compounding amount with respect to 0 part by weight is usually 1 to 100 parts by weight, preferably 10 to 60 parts by weight. When the amount of the hydrophilic compound (c) is too small, the dispersion stability of the lipophilic compound (b) is poor, and phase separation easily occurs. On the other hand, when the amount exceeds the above range, the curing property of the resole is impaired, and the hydrophilicity is high. The compound and the resole are easily phase separated.

In the present invention, the compounding ratio of the lipophilic compound (b) and the hydrophilic compound (c) is preferably in the range of 0.3 to 3, and when it is out of this range, the mixture is likely to undergo phase separation. Become.

As the curing agent used for curing the resol type phenolic resin (a) in the present invention, various known strongly acidic compounds, for example, inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, pyrophosphoric acid and polyphosphoric acid are used. , Organic acids such as phenolsulfonic acid, benzenesulfonic acid, toluenesulfonic acid, and metacresolsulfonic acid, or a mixture thereof. The amount of the curing agent used is usually in the range of 1 to 30 parts by weight with respect to 100 parts by weight of the resol type phenol resin.

The resin composition that can be used as a raw material for the activated carbon porous structure used in the filter for ozone decomposition of the present invention contains the above-mentioned components as essential components, but a small amount of other components other than the above, such as activated carbon. Disintegrating filler for improving the gas adsorption performance of the porous body, such as polyethylene, flour, etc., other carbon materials for diversifying the pore size, such as activated carbon, carbon black, mesophase pitch powder, graphite powder, etc. It may contain a metal salt compound or the like for promoting.

In the present invention, the resol-type phenolic resin (a) is a lipophilic compound having a boiling point of 100 ° C. or higher and is liquid at room temperature (b), and a hydrophilic liquid compound having a boiling point of 100 ° C. or higher (c) is used. If necessary, a mixture of a surfactant, other filler, etc. is stirred and mixed, and / or at the same time, a curing agent is mixed. As a method of mixing the above components, a method of continuously, batchwise, or simultaneously using a mixer having a stirring blade that rotates at high speed can be preferably used.

In the ozonolysis filter of the present invention, the viscosity of the resin composition used as a raw material immediately after stirring and mixing is usually 50,000 cps or less. Due to such a low viscosity, bubbles can not be mixed during stirring, and a homogeneous activated carbon porous material structure can be obtained in terms of bulk density and the like.

In the activated carbon porous material structure used for the filter for ozone decomposition of the present invention, the resin cured product thus obtained is used as it is, or after being cut into a plate-like body, it is carbonized in a non-oxidizing atmosphere. To make a carbon porous body. The non-oxidizing atmosphere means, for example, Ar gas, He gas, N2 gas, halogen gas, ammonia gas, CO gas, hydrogen gas, a mixed gas thereof, a water gas or the like. The temperature for carbonization is preferably in the range of 500 ° C to 1200 ° C, particularly 600 to 900 ° C.

The carbon porous body obtained as described above is
Further, activation treatment is applied to activate. The activation step may be continuous with the carbonization step or may be a step separate from the carbonization step. Activation of the carbon porous body is performed by heating the carbon porous body in an atmosphere of an oxidizing gas or a mixed gas of an oxidizing gas and an inert gas. Heating temperature is 600 ° C-120
The temperature is 0 ° C, preferably 750 to 1000 ° C. As the oxidizing gas, known oxidizing gases such as water vapor, carbon dioxide, oxygen, air and the like are used. These are usually mixed with an inert gas such as N2 for easy control.

The activated carbon porous body produced by the above method has a bulk density of preferably 0.3 g / cm 3 or more, particularly 0.4 g / cm 3 or more and 0.7 g / cm 3 or less,
It has a specific surface area of 700 m 2 / g or more.

The ozone decomposing filter according to the present invention comprises such an activated carbon porous material arranged in a flow path of air containing a malodorous component and the like.

Various shapes can be considered as the shape of the activated carbon porous material structure, and examples thereof include a plate shape, a rod shape, a plate shape with holes formed therein, and a honeycomb shape. Since the above-mentioned resin composition used in the present invention has a low viscosity, even such a complicated shape can be easily produced by casting or another molding method.

The activated carbon porous material structure, which is the main constituent material of the filter for ozone decomposition according to the present invention, may have a grid structure formed by arranging a plurality of activated carbon porous material structures at predetermined intervals. Such a grid structure is preferable because it is easy to manufacture and the pressure loss is small. For example, the wind speed is 1 m / m.
The pressure loss of 0.5 mmH2O or less can be reached at s.

[0024]

The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples unless it exceeds the gist. Example 1 {Production of activated carbon porous material structure} 100 parts by weight of a resole-type phenol resin (abbreviation: resole) having a viscosity at 25 ° C. of 4800 cps was used as a surfactant, and a sulfuric acid ester of a polyoxyethylene 2 mol adduct of castor oil was used. 5 parts by weight of sodium salt, a high boiling point hydrophilic compound having a molecular weight of 6
25 parts by weight of polyethylene glycol (abbreviated as PEG) of 00 and 25 parts by weight of liquid paraffin (abbreviated as flow para) as a high-boiling lipophilic compound are stirred for 5 minutes at a speed of 6000 rpm with a stirrer having three stages of pin blades. Stir well. The viscosity of this mixture was 3500 cps.

20 parts by weight of paratoluene sulfonic acid was added to this mixture as a curing agent, stirred at the same stirring speed for 1 minute, mixed and left in an air oven at 70 ° C. for 5 minutes and then taken out. After passing through while a myriad of cylindrical protrusions were formed, the porous plate of the polymer cured product was manufactured by further completely curing it in an air oven.

The porous plate of the polymer cured product was placed in an electric furnace, heated to 700 ° C. at a rate of 1.5 ° C./min in an N 2 atmosphere, kept at the same temperature for 1 hour, and then cooled. The carbon porous plate obtained by the above method was put in a ceramic fiber board box having a thickness of 3 mm, and this box was put in an electric furnace to obtain N2.
The temperature was raised to 900 ° C at a rate of 3 ° C / min, then N
The activating gas was introduced at a ratio of 2 / H2O = 9/1 for 3 hours, then cooled and taken out. In this way, the specific surface area of 950m
2 / g, bulk density 0.30 g / cm3, thickness 3.5 mm,
An activated carbon porous plate A having an opening ratio of 45% was obtained.

{Manufacture of Filter} A plate having a length of 100 mm and a width of 100 mm was cut out from the plate-like activated carbon porous body and fixed to a plastic frame to manufacture a filter for ozone decomposition.

{Performance Evaluation} [Pressure Loss] The above filter structure is set in a filter holder formed in a part of a 67 mmφ conduit, and a pressure gauge is arranged on each of the upstream and downstream sides of the holder. A blower for discharging air was attached, and the pressure loss due to the filter structure was measured as follows by operating these pressure gauges and blowers.
That is, after mounting the filter structure on the above holder, drive the blower to discharge the air through the conduit at a speed of 100 cm / sec, measure the pressure on the upstream side and the downstream side of the filter, and measure the pressure difference. The pressure loss was measured by indicating the loss (mmH2O).

[Ozone Decomposing Performance] An ozone generator is attached upstream of the above conduit. Operate the blower to discharge the air in the system at a speed of 50 cm / s and adjust the ozone concentration in the conduit to 10 ppm. Then attach the filter to the filter holder and immediately restart the blower. The concentration of ozone in the chamber after 10 minutes was measured by a gas detector tube. The test was terminated 1 hour after the test was started, and the weight residual ratio of the filter after the test was measured. The above measurement results are shown in the table. Shown in 1.

Example 2 In the filter structure of Example 1, the performance evaluation was performed in the same manner as in Example 1 except that the aperture ratio was adjusted to 60%. The results are shown in the table. Shown in 1.

Example 3 Instead of the raw resin composition used in Example 1, Example 1 was used.
100 parts by weight of the resole used in Example 5, 5 parts by weight of sodium sulfate of a polyoxyethylene 2 mol adduct of castor oil, 25 parts by weight of PEG having a molecular weight of 600, 25 parts by weight of liquid para, and 50 parts by weight of mesophase pitch powder. Example 1 was repeated except that the composition consisting of
Activated carbon porous plate B was obtained. A filter for ozone decomposition was produced from this activated carbon porous plate in the same manner as in Example 1, and the performance of the filter was evaluated in the same manner. The results are shown in the table. Shown in 1.

Comparative Example 1 The performance of a honeycomb activated carbon filter, which is commercially available as an ozone decomposition filter for a copying machine, was evaluated in the same manner as in Example 1. The results are shown in the table. Shown in 1

Comparative Example 2 Instead of the raw material resin composition used in Example 1, Example 1 was used.
100 parts by weight of the resol used in step 1, 10 parts by weight of paratoluene sulfonic acid as a curing agent, and CFC 1 as a blowing agent.
23b 2 parts by weight of the composition as a raw material was stirred and poured into a wooden mold, and the wooden mold was left in an air oven at 80 ° C. for 1 hour to be foam-molded. After curing, a block-shaped cured product was obtained. Was cut in the same manner as in Example 1 except that a plate having a thickness of 7 mm was obtained to obtain an activated carbon porous plate C. A filter for ozone decomposition having the same shape as in Example 1 was made from this activated carbon porous plate, and its performance was evaluated. The results are shown in the table.
Shown in 1.

[0034]

[Table 1]

[0035]

INDUSTRIAL APPLICABILITY The filter for ozonolysis of the present invention uses a composition comprising resol / lipophilic compound / hydrophilic compound as a raw material resin composition, whereby a composition having excellent fluidity can be obtained. Resin sheet can be molded,
Therefore, it can be formed into a thin wall having a thickness of about 1 mm and various shapes. Therefore, the filter can be thinner than before. In addition, the filter for ozone decomposition of the present invention is excellent in decomposition performance and long life because the activated carbon porous material used in the present invention has a high bulk specific gravity. In addition, since the activated carbon porous body, which is the main constituent material, has a large strength, no strength problem occurs. From the above points, the ozone decomposing filter of the present invention is more compact than the conventional one, and has an advantage that it does not take up a space in a facsimile, a copying machine or the like.

Claims (1)

[Claims] 1. Resol type phenolic resin (a) 100 parts by weight, lipophilic compound (b) 1 to 100 parts by weight which is liquid at room temperature and has a boiling point of 100 ° C. or more, hydrophilic 100 ° C.
The activated carbon porous structure obtained by carbonizing and activating the cured product of the composition comprising 1 to 100 parts by weight of the liquid compound (c) having the above boiling point is disposed in the air passage. Characteristic ozone decomposition filter.