JPH03221142A - Adsorbent indicator - Google Patents

Abstract

PURPOSE:To accurately display the adsorption amount of a malodorous sulfur compound by molding a mixture of a metal salt or metal oxide and activated carbon using a binder composed of plastic or a plastic powder. CONSTITUTION:A metal salt or metal oxide and activated carbon are mixed and the resulting mixture is molded using plastic or a plastic powder as a binder to obtain an adsorbent indicator of a malodorous sulfur compound. As the metal salt compound, a copper compound such as copper phosphate, copper sulfate or copper chloride or a lead compound such as lead sulfate or lead oxalate is pref. The latex being the binder for molding is composed of polyacrylonitrile or polybutadiene. Plastic is a thermoplastic resin or a thermosetting resin and the particle size thereof is pref. about 0.1-100mum.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a method for easily determining the lifespan of an adsorbent filter or a filter body.

Adsorbents are used in various fields, but during use they adsorb harmful substances and their performance deteriorates. If it is used for a long time in summer, it often loses its adsorption capacity and, without realizing it, the purifying effect is not obtained. Therefore, when these are used as filters, it is extremely preferable if the lifespan of the filter can be predicted by matching it with the residual capacity of the adsorbent, as this will make it possible to clarify when to replace the filter.

The present invention provides an indicator that changes in correlation with the residual adsorption capacity of an adsorbent for harmful substances, and a method of displaying the filter replacement time in accordance with the filter's residual adsorption capacity by incorporating this indicator. Particularly.

[Conventional technology]

Adsorbents have come to be easily used in ordinary households, but they deteriorate when used for a long period of time. In this case, there is a drawback that it is not possible to know exactly how much of the adsorbent's performance remains.

A conventional method of indicating when to replace a filter is, for example, pasting paper on the filter surface and predicting the service life based on the change in color. This takes advantage of the fact that when cigarette smoke comes in, the resin turns brown/C. However, when this method is used to purify gas that does not contain tobacco smoke, no discoloration to brown occurs, so even if the adsorbent has deteriorated, it will not be indicated.

There is also a method of using a battery and a miniature bulb that takes advantage of changes in battery voltage, but this method takes advantage of the fact that when the light is on, power is consumed and if the battery voltage drops, the miniature bulb disappears. . However, regardless of whether the harmful components in the gas to be treated are high or low in concentration, once a certain period of time has passed,
This would be extremely inappropriate as it would give instructions on the lifespan.

Alternatively, indicators unrelated to the residual performance of the adsorbent were often used, such as attaching a calendar and replacing it after a certain period of time. In this case, even if you do not use it, you will have to replace it when the time comes, which is wasteful.

Normally, the lifespan of a filter is that if it is exposed to high-concentration gas, it will deteriorate within a short period of time, but if it is exposed to low-concentration gas, it will last for a long time. Therefore, as an indicator of filter life, it is necessary to indicate the life according to the residual adsorption capacity of the adsorbent.

If the usage period and residual performance can be estimated in a manner that corresponds to the residual performance of the adsorbent, it will be possible to indicate the service life regardless of the usage period if the adsorbent deteriorates.

Such an indicator and a filter incorporating it are extremely effective industrially.

[Problem that the invention seeks to solve]

By processing a composition that exhibits an indicator function in accordance with the residual adsorption capacity of an adsorbent into a plate shape, a cylinder shape, a cylindrical shape, or a notebook shape and using it as an indicator,
The purpose of the present invention is to mold the indicator so that it can be built into the noiler, integrate it with the adsorbent, and provide an index related to the remaining life of the adsorbent.

[Means for solving problems]

A filter body incorporating an indicator and an indicator of the present invention can be obtained as follows.

Below, we will explain in detail the specifics of how it was made and how it was made.

(1) Indicator manufacturing method and performance (1) Types of indicators The indicator of the present invention can be used for hydrogen sulfide or aldehyde, that is, for hydrogen sulfide, a metal salt compound-activated system can be used. It can be used as an indicator corresponding to the cumulative absorption Wt of hydrogen sulfide. In this case, various metal compounds can be used as the gold TJX salt compound, but copper compounds such as copper phosphate, steel sulfate, and copper chloride, and lead compounds such as lead sulfate and lead oxalate are preferred.

4.Acrylic acid gel impregnated with silver nitrate and activated carbon react with aldehyde compounds such as acetaldehyde and formalin in a 1-to-1 ratio to precipitate silver at °C and reduce electrical resistance, so they can be used as aldehyde sensors. It is.

In order to obtain more accurate sensitivity, the shape of the indicator is preferably a shape that does not prevent contact with harmful components, such as a columnar shape, a plate shape, a linear shape, or a cylindrical shape.

(2) Manufacturing method of indicator The indicator of the present invention for hydrogen sulfide and aldehyde can be manufactured as follows. That is, it is obtained by thoroughly mixing 100 parts of a metal chloride with a particle size of 0.1 to 50 μm and activated carbon powder with a particle size of 0.1 to 50 μm in a range of 10 to 1000 parts and molding the mixture. By changing the mixing ratio of this mixed composition of metal salt and activated carbon, the sensitivity to the amount of adsorption can be changed. That is, when the amount of metal salt is small, a small amount of adsorption causes a large change, and when it is large, an indicator is obtained that does not change unless a large amount is adsorbed.

It is necessary to mold these mixtures into the required shape,
Latex or plastic powder can be used as a binder for molding.

As the latex, polyacrylonitrile, polybutadiene, polyarylate, polyvinyl acetate, carboxylmethylcellulose, methylcellulose, etc. can be used. The blending amount is 50 to 100 parts per 100 parts of mixture #J of gold g salt and activated carbon.

The particle size of glasstic is 0.1 to 100μ, which is good! The thickness is 5 to 50μ.

Here, the term "glasstic" refers to thermoplastic resins, thermosetting resins, water-soluble resins, conductive resins, and the like.

Thermoplastic resins include polyethylene/, polypropylene,
ABS, PET, nylon, PBT1 ethylene acrylic #4, PMMAJ14, Meso7Aze pitch, etc. can be used.

As the thermosetting resin, 7 run resin, phenol tM resin, etc. can be used.

As the hydrophilic resin, polyvinyl alcohol resin, EVAL resin, etc. can be used.

As the conductive resin, polyvinylpyrrole, polyacetylene, etc. can be used.

Reinforcing agent In order to improve the strength, a reinforcing agent may be added. As the reinforcing agent, glass fiber, carbon fiber, metal fiber, etc. can be used. II! The fiber diameter is 0.1-30μ, length d
0.5 to 10 cm is optimal. The amount added is 0.5 to 10 parts, preferably 2 to 5 parts.

Mixing Method As the mixing method, ordinary industrial mixing methods such as mixers, ribbon mixers, static mixers, ball mills, sample mills, kneaders, etc. can be used, but are not limited to these methods.

Molding method Platy, cylindrical, and cylindrical shapes can be made using methods such as extrusion molding, roll press, pellet mill, and tablet molding.

The lead wire for detecting electrical resistance can be sprayed with metal at both ends and soldered to it, or can be embedded in the molding process beforehand.
Alternatively, a method such as bonding with a conductive adhesive can be used.

The lead wire of the indicator may be brought out at a predetermined position within the filter mold frame and integrally molded.

As the lead wire, stainless steel wire, steel coated wire, enameled wire, etc. can be used.

■How to use the indicator When used alone, it can be used as an exposure amount indicator.

(2) Manufacturing method of built-in filter, performance failure/Decator can be used with Noilter containing an adsorbent to extract changes in electrical resistance in a form corresponding to the filter's residual adsorption capacity, so it is time to replace the filter. can be accurately predicted. gas phase,
Can be used in liquid phase.

If the general manufacturing method indicator is pellet-shaped, cylindrical, or cylindrical, it can be placed inside the filter. If it is plate-shaped, it will have a bottom shape as the outer frame of the filter.

[Adsorbent]

Any adsorbent can be used for the filter, such as activated carbon, zeolite, silica gel, alumina gel, etc.

Zeolites include natural zeolite, synthetic zeolite, movki, 5-,;/-7"5A, 3A, 4A,
13X.

ZSM-5 etc. can also be used.

The particle size of the adsorbent used in the present invention may be of any size as long as it meets the purpose of use. For gas phase filters, the particle size is 0.5-~
5- is good. Fii in case of liquid phase.

Mefu, tsuyu~32metsu/yu is good. However, it is not limited to this.

1 ft. The adsorbent may be in the form of crushed, pellet, granule, or in the form of a sheet, cloth, cloth, etc.A7). It may have any shape as long as it is necessary as a filter. For handling such as pressure loss and replacement, granulated carbon or a 7-piece adsorbent with an adsorbent attached may be convenient.

[Adhesive] It may be used as is, or it may be filled into a neuter in bulk. It may be molded into a block shape using a binder. Blocking has the advantage of being able to block the indicators all at once. Suitable plastics to be used as the binder are those that can be heat-fused without using water or organic solvents, such as thermoplastic glass and meso-7A pitch.

The plastic used in the present invention'/C may be one that can impart colorability, adhesiveness, and conductivity when attached to the surface of the adsorbent.

Furthermore, if a glass material can be selected, 7) If it can be given a composite function of a material and an adsorbent, it will become possible to develop even newer methods of condolence. Here, the term "glasstic" refers to thermoplastic resins, thermosetting resins, hydrophilic resins, conductive resins, and the like.

As mature plastic resin, polyethylene/, polypropyleno,
ABS, PET, nylon, PBT, ethylenenoacrylic fii resin, PMMA resin, mesophase pitch, etc. can be used.

As the thermosetting resin, 7 run resin, phenol fat control, etc. can be used.

Hydrophilic resins such as polyvinyl alcohol resin Everumi 1 resin can be used for the fingers.

As the conductive resin, polyvinyl pyrrole, polyacetylene, etc. can be used.

It is preferable to use different adhesive resins depending on the purpose of use. In other words, when used for adsorption of aqueous solutions, it is best to use hydrophilic polymers as adhesives, and when used for filtration of oils, organic solvents, etc., it is best to use hydrophobic polymers as adhesives. Preferable in terms of affinity for substances.

These particle diameters are o, i u m ~ 100
Pms is preferably 5 Pm to 50 μm, but is not limited to this.

[Manufacturing method]

The method of manufacturing the filter containing the indicator of the present invention is to coat or adhere adhesive powder to the surface of the adsorbent in advance, place the adsorbent particles and the indicator to be incorporated into a desired frame at the same time, and heat the filter. Obtained by crimping.

The particle size of the binder is N lpm-100Pm
Preferably, the range is not limited to 57 Am to 50 pm.

The ratio of the adhesive to the adsorbent varies depending on the particle size and specific gravity of the adsorbent, but it is preferably 2 to 10 parts by weight of plastic to 100 parts by weight of the adsorbent, but it is recommended to use the minimum necessary amount to prevent a decrease in adsorption capacity. Good in terms of preventing.

The impregnation can be carried out by mixing, and the mixing method may be a conventional industrial mixing method such as a mixer, ribbon mixer, static mixer, ball mill, sample mill, kneader, etc., but is not limited to this. At the time of mixing, adhesion can be achieved by mixing alone, but in order to strengthen the adhesion between the plastic and the adsorbent, it is better to perform simple heating. As a heat source, under the generation of static electricity or by simultaneously irradiating microwave, infrared rays, far infrared rays, high frequency, etc. during mixing,
Although it can be made stronger, it is not necessary to use these. Furthermore, by heating under reduced pressure during heating, it is possible to prevent low boiling point organic compounds generated from the adhesive from being adsorbed by the adsorbent, thereby preventing the adsorption capacity from decreasing. By increasing the molding pressure, a highly strong acid type body can be obtained.

By using this as a noirter in an air purifier and using a dedicated number, it is possible to accurately indicate its lifespan.

〔Effect of the invention〕

When used alone, it can be used as a sit indicator, and when incorporated into a filter, it can indicate the life of the filter, and in correspondence with the residual adsorption capacity, the entire life can be known. Specific effects will be explained below using Examples.

〔Example〕

Example l 100 parts by weight of powdered activated carbon, 100 parts by weight of phosphoric acid steel, and 35 parts of polyethylene powder with a particle size of 30 μm were thoroughly mixed, and this was prepared into a plate (10 x 50 x 1 theoretical sample 1).
Pellet (5ss*x30■sample 2), cylindrical inner diameter (2
Sample 3) with m*x outer diameter of 6 m*x20 m was molded under heat and pressure. Stainless steel wire glue 111i was attached to both ends of these. ! For 100 parts by weight of powdered activated carbon,
200 parts by weight of copper phosphate (sample 4)) and phosphoric acid w4300
parts by weight (sample 5)) and 35 parts of polyethylene powder with a particle size of 30 μm were mixed well, and this was prepared into a plate shape (10×50 μm).
×1■).

Figure 1 shows the change in electrical resistance of each sensor over time.

As shown in the figure, the electric resistance of the indicator of the present invention changes depending on the extreme gt of hydrogen sulfide, and the life indicator changes.
It has been shown to be effective.

Example 2 10 grams of PMMA gel with a water absorption rate of 100 times was dissolved in nitric acid*
Pour it into 1 liter of water containing 5g, let it absorb water, and make nitrate!
A PMMA gel containing 1 silver t-5Q wt % was obtained. This was extruded into a cylindrical shape with a diameter of 10 cm and dried at 150°C for 5 hours to obtain a silver nitrate-impregnated gel with a diameter of about 5 cm. (Sample 6) Lead iIA was attached to both ends of this sample and used as a hydrogen sulfide adsorption amount indicator.

FIG. 2 shows the relationship between the amount of hydrogen sulfide adsorption and electrical resistance.

As shown in the figure, the PMMA gel-silver nitrate molded article of the present invention can be used as a hydrogen sulfide adsorption amount indicator.

Example 3 Nitric acid #120 parts by weight, activated carbon powder 20 parts by weight, particle size 2
10 parts by weight of 0μ polypcopylene powder was thoroughly mixed, and the mixture was heated and molded into a plate shape of 10×50×1 size (sample 7).

In the same manner as in Example 1, acetaldehyde gas was introduced 2 d at a time. FIG. 3 shows the change in electrical resistance of the indicator at this time.

As shown in the figure, it can be clearly seen that the aldehyde indicator of the present invention can be an indicator corresponding to aldehyde adsorption 1.

Example 4 Hydrogen sulfide indicator sample 1 prepared in Example 1,
Using Samples 2 and 3, an air purifier filter with a built-in hydrogen sulfide indicator was created.

The plate-shaped sensor (sample 1) was used as part of the frame of the filter, and the pellet-shaped sensor (sample 2) was filled inside the filter together with pellet-shaped activated carbon. The cylindrical sensor (Sample 3) was placed inside the filter with the hole facing the direction of the wind flow.

The size of this filter was 17 mm x 19 cm x 9 m, and the amount of activated carbon charged was '/180 g. The hydrogen sulfide adsorption amount of this activated carbon before use was 28a6.

The air purifier containing this filter was placed in a box with an internal volume of 1 cubic meter, hydrogen sulfide was continuously injected, and changes in the electrical resistance of each sensor were measured.

Figure 4 shows the installation status of each sensor that can be placed on the filter, Figure 5
is the change in electrical resistance of each sensor over time. As shown in the figure, the electrical resistance of the filter of the present invention changes depending on the amount of hydrogen sulfide processed by the filter, making it clear that it is effective as a life sensor.

At this time, the amount of hydrogen sulfide adsorbed by the used activated carbon was 3.0%.
Met.

For comparison, in the case of a light bulb type indicator used as a lifespan indicator, the light did not go out because the light bulb was used for a short time.

The white paper from which the label was removed at the beginning of the 1fc stool is white tt.
There was no change. This is because the processing gas is not tobacco smoke.

It can thus be seen that the conventional indicators give value indications that are independent of the residual performance of the adsorbent in the filter.

Example 5 The aldehyde indicator prepared in Example 3 was molded into a filter in the same manner as in Example 4, and acetaldehyde gas ft2d was introduced in the same manner as in Example 4. FIG. 6 shows the change in electrical resistance of the indicator at this time.

The amount of acetaldehyde adsorbed by the activated carbon filled in this filter before use was 5 wt%, and the amount of acetaldehyde adsorbed by the activated carbon after use was Q, 2 vt%.

As shown in the figure, it can be seen that the filter with a built-in indicator of the present invention can indicate the lifespan corresponding to the acetaldehyde adsorption capacity.

[Brief explanation of drawings]

Figure 1 Example 1, relationship between hydrogen sulfide adsorption amount and electrical resistance Figure 2 Example 2, relationship between hydrogen sulfide adsorption amount and electrical resistance Figure 3 Example 3, relationship between aldehyde adsorption amount and electrical resistance Figure 4 Figure 5 Figure 6 Example 4, Example 4, Example 5, Air Film and Inday caterer layout plan Filter usage time and index Icator electrical resistance relationship Filter usage time and index Icator electrical resistance relationship

Claims (3)

[Claims] (1) An adsorption amount indicator for malodorous sulfur compounds made by mixing metal salts or metal oxides with activated carbon and molding the mixture with latex or plastic powder as a binder. (2) An adsorption amount indicator for malodorous sulfur compounds obtained by incorporating silver salt or silver oxide into a polymetal methacrylate gel. (3) An aldehyde adsorption amount indicator made by mixing silver salt or silver oxide with activated carbon and molding the mixture using latex or plastic powder as a binder.