JPS61137564A - Air drying and sterilizing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method of drying and sterilizing air.

Conventionally, various air sterilization devices and air drying devices have been used in factories manufacturing foods, medicines, electronic parts, and the like. The present invention provides a novel method for continuously drying and sterilizing air.

The present inventor used, as zeolite, a bactericidal agent made of a zeolite-based solid containing ion-exchanged metal ions having a bactericidal effect, and the water content of this zeolite was reduced to 15% by weight.
As mentioned above, we have found that a high and sustained sterilization effect can be obtained by keeping the concentration preferably between 15 and 25% by weight, and that if the drying process is performed after the sterilization process, air drying and sterilization can be carried out continuously without waste. The present invention has been completed.

That is, the present invention provides a method for drying and sterilizing air, in which the water content of the zeolite-based solid is increased to 15% by weight or more, preferably to a disinfectant made of a zeolite-based solid containing ion-exchanged metal ions having a bactericidal effect. 15~
It is dried by a method characterized by contacting with air while maintaining the concentration at 25% by weight, and then drying.

In the present invention, the bactericidal agent is one in which the ion-exchangeable part of a natural or synthetic zeolite made of aluminosilicate retains 1fIi or 1-j 2 [or more] of metal ions having a bactericidal effect.

Preferred examples of metal ions with bactericidal action are Aj', C
! Examples include u and Zn. Therefore, it is possible to use the above-mentioned metals having bactericidal properties alone or in combination for the above-mentioned purpose.

Zeolite is generally an aluminosilicate with a three-dimensionally developed skeleton structure, and generally contains 40 g of Al.
Based on XIJI/no'At! 03 '781
01・ZH! It is represented by O. M represents an ion-exchangeable metal ion, usually a monovalent to divalent metal, and n
corresponds to this valence. On the other hand, X and 1 represent the coefficients of metal oxide and silica, respectively, and 2 represents the number of crystallized water. Many types of zeolites are known, differing in their composition ratio, pore diameter, specific surface area, etc.

The solution of water-soluble salts of metals with bactericidal activity, such as silver, copper, and zinc, used in the present invention easily undergoes ion exchange with zeolite, so using this phenomenon, the above-mentioned metal ions can be extracted singly or It is possible to hold metal ions in a zeolite stationary phase by mixing them, but the zeolite particles holding metal ions have a specific surface area of 150 m''.
79 or above and 810! /A403 molar ratio is preferably 14 or less, particularly 11 or less. If not, the bactericidal effect will be poor. This is thought to be due to the fact that the amount of metal ions fixed on the zeolite is small in the deaf state that can exert its effect. In other words, it is considered that the amount of exchange groups, exchange rate, and accessibility of zeolite are attributed to which physicochemical properties.

Therefore, s I, known as molecular 7-p.
Zeolites with a large O2/A tz Os molar ratio are not preferred in view of the present invention.

Furthermore, when using zeolite with a molar ratio of s I ot/A40s of 14 or less, it is possible to uniformly retain metal ions having a bactericidal effect, and for this reason, a high bactericidal effect can be obtained by using such a zeolite. It turned out that it was possible. In addition, B to2 /ll of zeolite
The acid resistance and alkali resistance of zeolites with a high silica ratio and a molar ratio exceeding 14 increase with increasing StO, but on the other hand, the synthesis thereof takes a long time, and from an economical point of view, it is difficult to use such a high silica ratio. Using zeolite is not a good idea. The aforementioned s + o, /ht, o, ≦1
Natural or synthetic zeolite No. 4 can be used satisfactorily in the fields in which the present structure is normally considered in terms of its acid resistance and alkali resistance, and is also inexpensive and advantageous from an economic point of view. From this point of view, S'O! 'Al4
Advantageously, the 0s molar ratio is 14 or less.

S I O, /'A tgo3 used in the present invention
As the zeolite material having a molar ratio of 14 or less, any natural or synthetic zeolite can be used. For example, natural zeolite is Anal7 (Anal, -
C1m8: 8102/A403: ”b 6~5
．． 6 >, Chabailte
: 5IO1/A403 = 5 2~ &
0 and 4-7.6), clinoptilolite (C
11no-ptllollte: 8102/A
t203 = a 5 = 1 0. 5
'), Elio Suito (Kr1O
nl to: 8101/At! 03=
a 8 ~ 7.4), Faujasite (Fau,
+astte:5to2/Azto3 = 4.2~
4.6), mordenite (mordenite: 8)
101/A403= & 54~1Q, O), Phillipsite (Ph1111pslts: 5102.
/AttOs=2.6 to 4.4). These typically natural zeolites are suitable for the present invention. On the other hand, a typical synthetic zeolite is A-type zeolite (5102/At!03 = t 4~2.4
), X-type zeolite (s+oz, /htto, = 2
~5), Y-type zeolite (810,/Aj,O,=
= 5~6), mordenite (810,, -A403
= 9 to 10), but these synthetic zeolites are suitable as the zeolite material of the present invention. Particularly preferable ones are synthetic A-type zeolite, x-type zeolite, Y-type zeolite, and synthetic or It is natural mordenite.

In the present invention, the metal ions that perform the bactericidal action must be retained in the zeolite solid particles through an ion exchange reaction. If it is simply adsorbed or attached without ion exchange, the bactericidal effect and its sustainability will be insufficient.

As a method for retaining metal ions, zeolite can be immersed in a metal ion solution using an ion exchange reaction. For example, when converting various zeolites defined in the present invention to the AP-zeolite of the present invention, normally when converting kf-zeolite, nitric r1! A water-soluble solution of silver, such as silver, is used, but care must be taken not to increase its concentration too much. For example, 8- or X-type zeolites (sodium-
type) to Af-zeolite using an ion exchange reaction, if the silver ion concentration is too high (e.g.
2 MAfNO, when used) By ion exchange, silver ions are replaced with sodium zeo/ in the solid phase, and at the same time, silver oxides etc. are precipitated in the zeolite solid phase. For this,
The disadvantage is that the porosity of zeolite is reduced and the specific surface area is significantly reduced. Furthermore, even if the specific surface area does not decrease significantly, the bactericidal activity decreases due to the presence of silver oxide itself. In order to prevent such excess silver from being deposited on the zeolite phase, the concentration of the silver solution should be diluted, such as CL 5 MAPNO.
, it is necessary to maintain the following. Extremely safe AN
The concentration of o, is below CL1M. Such a concentration of A
When a PNO solution was used, the specific surface area of the Af-zeolite obtained was almost the same as that of the converted material zeolite, and it was found that the bactericidal effect could be exhibited under optimal conditions.

Next, when the zeolites defined in the present invention are converted to Cu-zeolite, the same phenomenon as in the case of AP-zeolite described above occurs depending on the concentration of the copper salt used for ion exchange. For example, when converting A-type or At the same time, basic precipitates such as Cu5(so,)I'0H)4 are precipitated in the zeolite solid phase, which reduces the porosity of the zeolite and significantly reduces the specific surface area. In order to prevent the precipitation of Cu-zeolite into the zeolite phase, it is preferable to keep the concentration of the water-soluble preparation used in a more dilute state, for example, 105 M or less.When using a 0uSO4 solution with such a concentration, the specific surface area of the Cu-zeolite obtained It was found that zeolite is almost equivalent to the converted material zeolite, and has the advantage of being able to exhibit its bactericidal effect in an optimal state.

It has been mentioned that during conversion to AP-zeolite and Cu-zeolite, solid matter may be deposited on the υzeolite solid phase depending on the concentration of salts used for ion exchange.
-When converting to zeolite, the salts used are
This phenomenon is not observed near 3M. Generally, the Zn-zeolite used in the present invention can be easily obtained by using salts having concentrations around the above range.

AP-zeolite, Cu-zeolite and Zn as mentioned above
- When carrying out the ion exchange reaction by the patch method during conversion to zeolite, the zeolite material may be immersed in a salt solution having the above-mentioned contact area. In order to increase the metal content in the zeolite material, the number of patch treatments may be increased. On the other hand, when treating a zeolite material by a column method using a salt solution having the above concentration, the desired metal-zeolite can be easily obtained by filling an adsorption tower with the zeolite material and passing the salt solution through it. can get.

The amount of metal in the metal-zeolite (based on anhydrous zeolite) is not more than 30% by weight of silver, and the preferred range is α001 to 5% by weight. - Regarding the copper and zinc used in the strength wood invention, the amount of copper or zinc occupied in the metal-zeolite (based on anhydrous zeolite) is 35% by weight or less, and the preferable range is from 0.01 to
It is also possible to use silver, copper and zinc ions at 15% by weight in combination; in this case, the total amount of metal ions is 35% by weight or less than 1% of the metal-zeolite (based on anhydrous zeolite). The preferred range depends on the composition ratio of metal ions, but the range is 70, QQ1 to 15.
Shigekei Chi Nichiru.

However, even if metal ions other than silver, copper, and zinc, such as sodium, potassium, calcium, or other metal ions, coexist, the bactericidal effect is not hindered, so the residual or coexistence of these ions is not a problem.

The zeolite containing bactericidal metal ions through ion exchange as described above can be in powder form, in the form of pellets made by solidifying the powder according to a conventional method, or in the form of a porous body with many voids formed from the powder. It can be any shape. Alternatively, the zeolite can be a fine powder dispersed and supported within an organic polymer. In this case, the shape of the zeolide can be from 1 micron to several tens of microns or several hundred microns, and the organic polymer itself can be in any shape such as fibrous or granular. Methods for dispersing and supporting the sterilizing metal-containing zeolite within an organic polymer include, for example, adding the zeolite to raw material monomers and mixing and polymerizing them, adding and mixing them to a reaction intermediate, and adding the zeolite to the polymer at the end of polymerization. There are a method of mixing, a method of adding and mixing to polymer pellets and molding, a method of adding and mixing to a dope for molding, for example, a spinning dope (4)
? Zeolite can also be used in the form of being dispersed and supported in an organic or inorganic foam capable of finely distributing air.

In the above, it was described that the zeolite-based solid containing bactericidal metal ions is converted into a usage form, but this order is reversed and the zeolite-based solid is first turned into a usage form, and then the zeolite-based solid is converted into a usage form.
The germicidal metal ions can also be retained in the zeolite by ion exchange in the same manner as described above. In this case, zeolite solid particles supported on organic polymers such as fibers can also be sufficiently ion-exchanged (Japanese Patent Application Laid-Open No. 135235/1983).

In the present invention, the bactericidal action of the bactericidal metal ions retained in the zeolite solid is thought to be due to the conversion of oxygen to ozone by the catalytic action of the metal, which oxidizes bacterial enzymes and kills the bacteria.

However, it has been found that this bactericidal effect is not sufficiently effective unless the zeolite solid contains a certain amount of water. moisture content,
Preferably, it is necessary to have a moisture content of 15 to 25% by weight.

Therefore, in the air drying and sterilization method of the present invention, it is necessary to perform the drying step after the sterilization step. Otherwise, a separate means would be required to maintain the moisture content of the zeolite solid particles within the above range, and it would be unreasonable for air once dried to absorb moisture again during the sterilization process. Chiru.

Here, the drying step itself can be performed by a conventionally known method. For example, air can be passed through a column packed with conventional desiccants.

The desiccant is not particularly limited, but for example, zeolite particles, alumina gel particles, activated carbon, silica gel, or a mass formed by adhesively molding these can be used.

Moreover, as an operating method for the drying process, a so-called PSS method, which cycles the steps of adsorption, depressurization, purge, and pressurization, can be adopted.

As shown in FIG. 1, the apparatus for carrying out the method of the present invention includes first passing air through a sterilizing column 1 filled with a sterilizing agent, and then passing air through one of two drying columns. 2 is subjected to a regeneration process to absorb and remove water 5
In normal use, the regeneration process of the bacterial column filled with sterilizing agent A and desiccant agent A is almost unnecessary, or as shown in Figure 2, two sterilizing/drying columns filled with 1 sterilizing agent A and 1 desiccant agent A are prepared. Then, air is passed through the sterilizer-filled side of one column to sterilize and dry it, and the other column is subjected to regeneration treatment.6 As described above, according to the present invention, sterilization and drying can be carried out continuously and efficiently. A possible method was provided.

[Brief explanation of the drawing]

1 and 2 are flow diagrams of an apparatus for carrying out the method of the present invention, and the numbers in the hollows indicate the following: 1: Sterilizing column 2: Drying column a: Sterilizing agent b = desiccant. Figure 2

Claims (1)

[Claims] 1. In a method for drying and sterilizing air, a sterilizing agent consisting of a zeolite solid containing ion-exchanged metal ions having a sterilizing effect has a moisture content of 15% by weight or more. A method characterized by contacting with air while maintaining the temperature, and then drying. 2. The method according to claim 1, wherein the metal ion having a bactericidal effect is one or more metal ions selected from the group consisting of silver, copper, and zinc. 3. The moisture content of the zeolite solid is 15% by weight to 25% by weight.
% by weight. 4. The method according to claim 1, wherein the zeolite solid has a specific surface area of 150 m^2/g or more and a SiO_2/Al_2O_3 molar ratio of 14 or less. 5. The method according to claim 1, wherein the zeolite solid is composed of A-type zeolite, X-type zeolite, Y-type zeolite or mordenite. 6. The method according to claim 1, wherein the zeolite solid is formed into a porous body with many voids. 7. The method according to claim 1, wherein the zeolite solid is supported in particulate form and dispersed in the fibers.