JP6224007B2 - Gas generating apparatus and gas generating method - Google Patents

Description

  One aspect of the present invention relates to a gas generation apparatus and a gas generation method, and more particularly to an apparatus that generates a gas such as chlorine dioxide or carbon dioxide by reaction.

  Conventionally, it is known to perform, for example, indoor sterilization and deodorization using a device that generates a gas such as chlorine dioxide. Patent Document 1 discloses a gas generator for generating chlorine dioxide gas by bringing gelled stabilized chlorine dioxide and granular citric acid into contact with each other, and a storage container body for storing gelled stabilized chlorine dioxide, A granular citric acid containing part having a lead-out hole for dropping citric acid onto the stabilized chlorine dioxide and a cover part of the storage container body, and the granular citric acid is led out by rotating the cover part Is described that falls on stabilized chlorine dioxide to generate gas.

  Patent Document 2 discloses a gas generation method for generating chlorine dioxide gas by sucking an aqueous solution of chlorous acid into a suction part by capillary action and bringing the aqueous solution of chlorous acid and a decomposing agent into contact with each other through the suction part. An apparatus is described.

JP 2009-256141 A Japanese Patent Laid-Open No. 2-164702

  For example, in a gas generator used for indoor sterilization and deodorization, it is required to stably and continuously generate a gas such as chlorine dioxide. In the invention described in Patent Document 1, the amount of gas generated can be controlled to some extent by making the chemical substance to be mixed into a gel or granular form. However, since the apparatus described in Patent Document 1 needs to drop granular citric acid on stabilized chlorine dioxide by generating vibration when generating chlorine dioxide gas, the generation of chlorine dioxide is stabilized. There is a problem in its sustainability.

  On the other hand, as described in Patent Document 2, it is conceivable to use a structure in which chlorine dioxide is continuously generated by sucking up an alkaline aqueous solution using a capillary phenomenon and gradually bringing it into contact with an acid. However, in this configuration, a large amount of gas is generated at a time when the acid dissolved in the aqueous solution flows backward, and then the amount of generated gas is greatly reduced in a short time, so that the stability and sustainability are poor. It was found that there was a problem.

  Therefore, an object of one aspect of the present invention is to provide a gas generation apparatus and a gas generation method that improve stability and sustainability in generation of gases such as chlorine dioxide and carbon dioxide.

  In order to solve the above-described problem, one aspect of the present invention is a gas generator that generates a gas by a reaction between an alkali and an acid, the container containing an aqueous solution containing one of an alkali and an acid, and a container outside the container. A solid material including the other of the alkali and the acid, and a liquid absorbing member disposed so as to protrude from the inside of the container to the outside of the container, and for sucking out the aqueous solution in the container toward the solid material outside the container, In addition, the solid is poorly water soluble.

  According to the gas generator according to one aspect of the present invention, the aqueous solution containing one of alkali and acid is gradually absorbed by the liquid absorbing member, and the solid and the aqueous solution containing the other of alkali and acid are the liquid absorbing member. By reacting continuously and gently through the gas, gases such as chlorine dioxide and carbon dioxide can be generated stably and continuously. In addition, according to this gas generator, the use of a hardly water-soluble solid material prevents the solid material from dissolving in the aqueous solution and backflowing the liquid absorbing member, so that the reaction proceeds rapidly and a large amount at a time. It is avoided that the amount of gas generated or the amount of gas generated decreases greatly in a short period of time, and the stability and sustainability of gas generation can be greatly improved.

In the gas generator according to one aspect of the present invention, the solid material may be a mixture mixed with a water-absorbing polymer.
In this case, a mixture of an acid or alkali and a water-absorbing polymer is used as a solid, and the water-absorbing polymer sucks up the aqueous solution and keeps it wet, so that the acid and alkali react more continuously and gently. Gases such as chlorine dioxide and carbon dioxide can be generated more stably and stably.

  A gas generation method according to another aspect of the present invention is a gas generation method in which a gas is generated by a reaction between an alkali and an acid, and an aqueous solution containing one of alkali and acid is contained in the container from the container by a liquid absorbing member. The gas is generated by the reaction between the aqueous solution and the solid substance outside the container, and the solid substance contains the other of alkali and acid and is poorly water-soluble.

  According to the gas generation method according to one aspect of the present invention, the aqueous solution containing one of alkali and acid is gradually absorbed by the liquid absorbing member, and the solid and the aqueous solution containing the other of alkali and acid are the liquid absorbing member. By reacting continuously and gently through the gas, gases such as chlorine dioxide and carbon dioxide can be generated stably and continuously. In addition, according to this gas generation method, the use of a poorly water-soluble solid material prevents the solid material from dissolving in the aqueous solution and flowing back through the liquid absorbing member, so that the reaction proceeds rapidly and a large amount is produced at a time. It is avoided that the amount of gas generated or the amount of gas generated decreases greatly in a short period of time, and the stability and sustainability of gas generation can be greatly improved.

In the gas generation method according to one aspect of the present invention, the solid material may be a mixture mixed with a water-absorbing polymer.
In this case, a mixture of an acid or alkali and a water-absorbing polymer is used as a solid, and the water-absorbing polymer sucks up the aqueous solution and keeps it wet, so that the acid and alkali react more continuously and gently. Gases such as chlorine dioxide and carbon dioxide can be generated more stably and stably.

  According to the gas generating device and the gas generating method according to one aspect of the present invention, it is possible to avoid that a large amount of gas is generated at a time or the amount of generated gas is greatly reduced in a short period of time. As a result, the generation of gases such as chlorine dioxide and carbon dioxide can be stabilized, and the sustainability of the gas generation can be greatly improved. In addition, since a large amount of gas such as chlorine dioxide and carbon dioxide is not generated at a time, it is excellent in safety.

It is sectional drawing which shows one Embodiment of the gas generator which concerns on 1 side of this invention. It is the schematic for demonstrating the measurement conditions of the generation amount of gas. It is a graph which shows the generation amount of chlorine dioxide. It is a graph which shows the generation amount of chlorine dioxide at the time of using the mixture of a fumaric acid and a water absorbing polymer. It is a graph which shows the generation amount of a carbon dioxide.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

(Gas generator)
As shown in FIG. 1, a gas generator 1 according to this embodiment includes a container 2 that contains an alkaline aqueous solution L, a liquid absorbent core 3 that is disposed in the container 2 in contact with the alkaline aqueous solution L, A liquid-absorbing mat 4 connected to the upper end of the liquid-absorbent core 3, a non-woven bag 5 disposed on the liquid-absorbing mat 4 and holding the acid solid S, and a lid of the container 2 covered from above the non-woven bag 5 6 are provided.

  The gas generator 1 is a so-called upright device, and the bottle-like container 2 has an opening on the upper side. What is necessary is just to set the internal volume of the container 2 suitably with the kind of gas to generate | occur | produce, a place of use, etc. The material of the container 2 may be any material that does not leak liquid and does not react with chlorite or the like, and may be any resin such as polyethylene terephthalate, paper, metal, ceramic, or glass. Moreover, the shape of the container 2 is not limited to the shape shown in FIG.

  As the liquid stored in the container 2, an appropriate alkaline aqueous solution L corresponding to the type of gas to be generated is selected. When chlorine dioxide is generated, the liquid stored in the container 2 may be an aqueous solution of chlorite. Specific examples of the aqueous solution of chlorite include an aqueous solution of an alkali metal salt of chlorous acid (for example, sodium chlorite), an aqueous solution of an alkaline earth metal salt (for example, calcium chlorite), and the like. More specifically, it can be a sodium chlorite aqueous solution. The concentration of the aqueous solution L is appropriately set according to the concentration and duration of the generated gas. When carbon dioxide is generated, the liquid stored in the container 2 may be an aqueous carbonate solution. Specific examples of the carbonate aqueous solution include sodium bicarbonate and sodium carbonate.

  The combination of the aqueous alkaline solution L and the acid solid S is not necessarily required, and the combination of the aqueous acid solution L and the alkaline solid S may be used. Details of the combination of the acid aqueous solution L and the alkali solid S will be described later.

  The liquid absorption core 3 is a member for sucking up the alkaline aqueous solution L in the container 2 by capillary action. The material of the absorbent core 3 is not particularly limited as long as it can absorb the alkaline aqueous solution L and does not react with chlorite, and is an organic material such as resin or pulp, or a porous material such as glass or other inorganic material. Can be used. As a suitable example of a porous material, the nonwoven fabric which consists of a pulp or a resin material is mentioned. As the resin material, one kind selected from polyethylene terephthalate, acrylic resin, polypropylene, and polyethylene may be used alone, or two or more kinds may be used in combination. In addition, when using the acid aqueous solution L, the material of the liquid absorption core 3 should just absorb the acid aqueous solution L, and should not react with an acid.

  The liquid absorbent core 3 is disposed so as to protrude from the inside of the container 2 to the outside of the container 2, and is connected to the liquid absorbent mat 4 outside the container 2 through an opening above the container 2. The liquid absorption mat 4 is disposed so as to close the opening of the container 2 from above. The liquid absorbent mat 4 is impregnated with the alkaline aqueous solution L sucked up by the liquid absorbent core 3, and the nonwoven fabric bag 5 is disposed on the upper surface thereof.

  The material of the liquid absorbent mat 4 is only required to be able to suck up the alkaline aqueous solution L, and may be the same type as the liquid absorbent core 3 described above, or a different material may be adopted. Moreover, the liquid absorption core 3 and the liquid absorption mat 4 may each be comprised with several material. For example, the absorbent core 3 and the absorbent mat 4 are made of pulp as a main raw material and bonded with a binder, and a tissue-like pulp material, non-woven fabric or the like is pasted on the front and back surfaces for surface strength and shape retention. It is good also as a structure.

  Parameters such as porosity, density, or cross-sectional size perpendicular to the longitudinal direction of the porous material constituting the liquid absorbent core 3 and the liquid absorbent mat 4 are appropriately set according to various conditions such as the viscosity of the liquid and the height of the container 2. do it. The liquid absorbent core 3 and the liquid absorbent mat 4 function as a liquid absorbent member for sucking out the alkaline aqueous solution L in the container 2 toward the acid solid S outside the container 2. In addition, the structure of a liquid absorption member is not limited to the liquid absorption core 3 and the liquid absorption mat 4 shown in FIG.

The non-woven bag 5 is for holding the acid solid S. The acid solid S is held in the non-woven bag 5 as a mixture with the water-absorbing polymer. Details of the acid solid S will be described later. The nonwoven fabric bag 5 is a bag formed of a nonwoven fabric having a basis weight of about 20 g / m ² , and a part of the inner mixture comes into contact with the alkaline aqueous solution L soaked from the liquid absorbent mat 4 through the eyes of the nonwoven fabric. An organic material such as resin or pulp can be used as the material of the nonwoven fabric bag 5. In the case where the acid solid S is not a mixture but a tablet or the like, it is sufficient to select and use a coarse-grained one. Select and use.

  The nonwoven fabric bag 5 functions as a holding body for holding the acid solid material S. This holding body does not necessarily need to be the nonwoven fabric bag 5, and may be a mesh bag or a housing or frame having a large number of openings. Further, the material of the holding body may be any material as long as it can be stably held without reacting with an acid, and pulp, resin, or the like can be adopted. In addition, in order to hold | maintain the acid solid substance S, it is not necessary to use bags, such as a nonwoven fabric. A container, a frame, an arm, or the like that appropriately holds the acid solid substance S may be used, and a solid acid such as a mixture of the acid solid substance S and a water-absorbing polymer or a tablet is directly applied to the liquid-absorbing mat 4. You may arrange. Further, the liquid absorbent mat 4 may be used in a state of being folded so as to wrap the acid solid matter S. In addition, when using the alkali solid substance S, the material of the nonwoven fabric bag 5 should just be able to hold | maintain stably, without reacting with an alkali. Furthermore, it is not always necessary to provide a holding body such as the nonwoven fabric bag 5.

In the nonwoven fabric bag 5, the water-absorbing polymer contained in the acid solid S absorbs the alkaline aqueous solution L soaked in the liquid-absorbing mat 4 and swells. Since the water-absorbing polymer is kept wet, the acid mixed with the water-absorbing polymer continuously and gently reacts with the alkaline aqueous solution L, and gases such as chlorine dioxide and carbon dioxide are continuously generated.

The acid solid material S is a solid containing a hardly water-soluble acid. The slightly water-soluble acid means an acid having a solubility at 25 ° C. of 6 [g / 100 mL-H ₂ O] or less. Specific examples of the hardly water-soluble acid include organic acids such as fumaric acid and benzoic acid, and inorganic acids such as boric acid.

  Moreover, the acid solid substance S can generate | occur | produce the gas stably and continuously by being made into the mixture mixed with the water absorbing polymer as mentioned above. As the water-absorbing polymer constituting the acid solid S, a neutral or acidic polymer that is difficult to be decomposed by an acid can be used. Specifically, polyacrylic acid can be used as the water-absorbing polymer. The blending amount of the water-absorbing polymer is appropriately selected according to the type of the water-absorbing polymer, the target duration of gas generation, the amount of the aqueous solution L, the hydrophilicity of the components of the solid material S, and the like. The blending amount of the water-absorbing polymer is selected so that at least the total liquid-absorbing amount of the water-absorbing polymer does not exceed that of the aqueous solution L.

  Such a mixture is obtained, for example, by mixing and preparing a powdery organic acid and a powdery or granular water-absorbing polymer. Specifically, a mixture of fumaric acid and polyacrylic acid (for example, trade name “Junron PW-312” manufactured by Toagosei Co., Ltd.) can be used as the acid solid S. The content ratio of the organic acid in the mixture can be 60% or more and 90% or less. The acid solid S is not limited to a mixture with a water-absorbing polymer, and a tablet-like, granular, or gel-like acid may be used alone.

  The lid 6 is a cylindrical lid that covers the upper side of the container 2. The lid 6 is placed on the container 2 so as to accommodate the nonwoven fabric bag 5 and the liquid absorbent mat 4 inside. The same material as the container 2 can be adopted as the material of the lid 6. The material of the lid 6 may be the same as or different from that of the container 2.

  A plurality of openings for discharging the generated gas are formed on the upper surface and side surfaces of the lid portion 6. The lid 6 has an opening having an appropriate shape and area so that the generated gas can be efficiently discharged while preventing external contact with the liquid absorbent mat 4 and the nonwoven fabric bag 5 where a chemical reaction occurs. The shape of the lid 6 and the position of the opening are not limited to those shown in FIG.

(Gas generation method)
Next, a gas generation method using the gas generator 1 will be described. As shown in FIG. 1, in the gas generator 1, the alkaline aqueous solution L in the container 2 is sucked up by the liquid absorbent core 3 and impregnated in the liquid absorbent mat 4. The alkaline aqueous solution L impregnated in the liquid absorbent mat 4 is immersed in the nonwoven fabric bag 5 and sucked up by the water absorbent polymer constituting the acid solid material S held therein, and the water absorbent polymer swells and becomes wet. keep. The acid mixed with the water-absorbing polymer reacts with the alkaline aqueous solution L. By this reaction, a gas such as chlorine dioxide or carbon dioxide is generated and diffuses outside through the opening of the lid 6.

  According to the gas generator 1 and the gas generation method according to the present embodiment described above, the alkaline aqueous solution L is gradually sucked up by the liquid absorbent wick 3, and the acid solid S and the alkaline aqueous solution L are absorbed by the liquid absorbent wick 3 and the liquid absorbent mat. By reacting continuously and gently via 4, gases such as chlorine dioxide and carbon dioxide can be continuously generated.

  Moreover, according to the gas generating device 1 and the gas generating method, by using the hardly water-soluble acid solid S, the acid solid S is dissolved in the alkaline aqueous solution L, and the liquid absorbent core 3 and the liquid absorbent mat 4 flow backward. Can be suppressed. Therefore, according to the gas generator 1 and the gas generation method, it is possible to avoid the chemical reaction from proceeding rapidly due to the backflow of the dissolved acid solid S, and to greatly reduce the gas generation amount in a short time thereafter. Stability and sustainability can be greatly improved.

  Furthermore, according to the gas generator 1 and the gas generation method, a mixture of an acid and a water-absorbing polymer is adopted as the acid solid S, and the water-absorbing polymer sucks up the alkaline aqueous solution L and keeps it in a wet state. And the alkaline aqueous solution L react more continuously and gently, so that gases such as chlorine dioxide and carbon dioxide can be generated more stably and continuously.

  The present invention is not limited to the embodiment described above. For example, instead of the combination of the alkaline aqueous solution L and the acid solid product S, a combination of the acid aqueous solution L and the alkaline solid product S may be adopted.

  In this case, the acid aqueous solution L can be an organic acid aqueous solution or an inorganic acid aqueous solution. Specific examples of the organic acid aqueous solution include an aqueous solution of a carboxylic acid. More specifically, an aqueous solution of citric acid, an aqueous solution of malic acid and the like can be mentioned. Specific examples of the inorganic acid aqueous solution include an aqueous hydrochloric acid solution and an aqueous phosphoric acid solution. The concentration of the acid aqueous solution L is appropriately set according to the concentration and duration of the gas to be generated.

The alkali solid S is a solid containing a hardly water-soluble alkali. The slightly water-soluble alkali means an alkali having a solubility at 25 ° C. of 6 [g / 100 mL-H ₂ O] or less. When chlorine dioxide is generated, calcium chlorite can be employed as a specific example of a poorly water-soluble alkali. In the case of generating carbon dioxide, calcium carbonate can be employed as a specific example of the poorly water-soluble alkali.

  The alkali solid S can be a mixture containing a water-absorbing polymer. As the water-absorbing polymer constituting the alkali solid S, a neutral or alkaline polymer that is difficult to be decomposed by an alkali can be used. Specifically, sodium polyacrylate is mentioned.

  Even in such a combination of the acid aqueous solution L and the hardly water-soluble alkali solid S, the same effects as those of the combination of the alkali aqueous solution L and the acid solid S can be obtained. That is, also in this case, according to the gas generator 1 and the gas generation method described above, the acid aqueous solution L is gradually sucked up by the liquid absorbent core 3, and the acid aqueous solution L and the alkali solid substance S are absorbed by the liquid absorbent core 3 and the liquid absorbent. By continuously and gently reacting via the mat 4, gases such as chlorine dioxide and carbon dioxide can be continuously generated.

  In addition, the structure of the gas generator 1 described above is not necessarily an upright type, and may be an inverted type in which the container 2 that stores the aqueous solution L opens downward. Moreover, it is not prevented that the container 2 is a horizontal type that opens sideways. In addition, the gas generator 1 may generate carbon dioxide instead of chlorine dioxide that performs sterilization and deodorization in the room. In this case, for example, an aqueous solution L of carbonate (for example, sodium bicarbonate) and an organic acid (for example, fumaric acid) may be used. Carbon dioxide is effective in attracting and capturing mosquitoes.

  Hereinafter, although one side of the present invention is explained in detail by an example and a comparative example, the present invention is not limited to the following examples. First, the case where chlorine dioxide is generated will be described.

Example 1
As shown in FIG. 2, the gas generator 1 shown in FIG. 1 was disposed in a desiccator 10 having an internal capacity of 4L. Here, the material of the container 2 of the gas generator 1 and the material of the liquid absorbent core 3 (diameter 8 mm, length 115 mm, basis weight 18 g / m) are polyethylene terephthalate, liquid absorbent mat 4 (area 34 cm ² , thickness 12 mm, basis weight). The material of 1200 g / m ² ) was a composite of pulp and synthetic fiber, the non-woven bag 5 (weight per unit area 20 g / m ² ) was polyethylene terephthalate, and the material of the lid 6 was polyethylene.

  In the container 2 of the gas generator 1, 300 mL of an aqueous sodium chlorite solution having a concentration of 7.5% by weight as the alkaline aqueous solution L was accommodated. In the non-woven bag 5, 20 g of slightly water-soluble fumaric acid as powdered acid solid S was put. Inside the desiccator 10, a fan 11 for stirring air was installed, and the temperature inside the desiccator 10 was maintained at 25 ° C. A detector tube 12 for measuring the amount of gas generated was connected to the desiccator 10. As the detection tube 12, 23M, 8H manufactured by GASTEC was used.

  The amount of chlorine dioxide generated by placing the gas generator in the desiccator 10 in a state where chlorine dioxide is generated by a chemical reaction, driving the fan 11 and sucking the air in the desiccator 10 into the detection tube 12 after 3 minutes. Was measured.

(Example 2)
The same procedure as in Example 1 was conducted except that 20 g of slightly water-soluble benzoic acid was used as the acid solid S.

(Comparative Example 1)
The same procedure as in Example 1 was performed except that 20 g of citric acid that was not slightly water-soluble was used as the acid solid S.

(Comparative Example 2)
As acid solid substance S, it carried out similarly to Example 1 except having used 20 g of malic acid which is not sparingly water-soluble.

  FIG. 3 shows changes over time in the amount of chlorine dioxide generated in Examples 1 and 2 and Comparative Examples 1 and 2. The vertical axis in FIG. 3 represents the chlorine dioxide concentration (ppm), and the horizontal axis represents the number of days elapsed.

  As a result of the experiment, in Examples 1 and 2, the generation amount of chlorine dioxide was stably maintained over 35 days, whereas in Comparative Examples 1 and 2, the chemical reaction was excessive in a short period (several days). As a result, a large amount of gas was generated immediately after the start of the reaction, and then the amount (concentration) of chlorine dioxide rapidly decreased. In Comparative Examples 1 and 2, the generation amount of chlorine dioxide continued to decrease thereafter, and after 25 days, the results were lower than Examples 1 and 2. In Examples 1 and 2, the generation amount maintaining the chlorine dioxide concentration of about 2 ppm was stably obtained for a long time.

(Example 3)
Similarly to Example 1, the gas generator 1 shown in FIG. 1 was used. The container 2 of the gas generator 1 contained 300 ml of an aqueous sodium chlorite solution having a concentration of 5% by weight as the alkaline aqueous solution L. The non-woven bag 5 has 10 g of slightly water-soluble fumaric acid as powdered acid solid S and polyacrylic acid (trade name “Junron PW-312”, Junlon is a registered trademark) 2.5 g Was added to the mixture.

  Inside the desiccator 10, a fan 11 for stirring air was installed, and the temperature inside the desiccator 10 was maintained at 25 ° C. A detector tube 12 for measuring the amount of gas generated was connected to the desiccator 10. As the detection tube 12, 23M, 8H manufactured by GASTEC was used.

  The amount of chlorine dioxide generated by placing the gas generator in the desiccator 10 in a state where chlorine dioxide is generated by a chemical reaction, driving the fan 11 and sucking the air in the desiccator 10 into the detection tube 12 after 3 minutes. Was measured.

(Comparative Example 3)
The same procedure as in Example 1 was performed except that 20 g of citric acid that was not slightly water-soluble was used as the acid solid S.

(Comparative Example 4)
As acid solid substance S, it carried out similarly to Example 1 except having used 20 g of malic acid which is not sparingly water-soluble.

  FIG. 4 shows the changes over time in the amount of chlorine dioxide generated in Example 3 (fumaric acid + polyacrylic acid), Comparative Example 3 (citric acid), and Comparative Example 4 (malic acid). The vertical axis in FIG. 4 indicates the chlorine dioxide concentration (ppm), and the horizontal axis indicates the number of days elapsed.

  As a result of the experiment, in Example 3, the generated amount of chlorine dioxide was stably maintained over 55 days, whereas in Comparative Examples 3 and 4, the chemical reaction proceeded excessively in a short period (several days). A large amount of gas was generated immediately after the start of the reaction, and then the amount of chlorine dioxide generated rapidly decreased. In Comparative Examples 3 and 4, the generation amount of chlorine dioxide continued to decrease thereafter, and the results after Example 25 were lower than Example 3. Moreover, compared with Examples 1 and 2, Example 3 was able to obtain the generation amount which brings about 2.5 times as much chlorine dioxide concentration on the 56th day.

  Furthermore, in Example 3, the concentration of the aqueous sodium chlorite solution is 5% by weight, which is less than the concentration of 7.5% by weight of Examples 1 and 2, and sufficient chlorine dioxide over 55 days. The amount of generation was kept. That is, by using fumaric acid as a mixture with polyacrylic acid, it was possible to efficiently maintain more stable generation of chlorine dioxide.

  Next, the case where carbon dioxide is generated will be described.

Example 4
Similarly to Example 1, the gas generator 1 shown in FIG. 1 was used. The container 2 of the gas generator 1 contained 300 ml of an aqueous citric acid solution having a concentration of 10% by weight as the aqueous acid solution L. In the non-woven bag 5, 30 g of poorly water-soluble calcium carbonate as a powdery alkali solid S and 1.0 g of sodium polyacrylate (trade name “Leogic”, registered trademark) manufactured by Toagosei Co., Ltd.) are mixed. The mixed mixture was added.

  Inside the desiccator 10, a fan 11 for stirring air was installed, and the temperature inside the desiccator 10 was maintained at 25 ° C. A detector tube 12 for measuring the amount of gas generated was connected to the desiccator 10. As the detection tube 12, 2LL manufactured by GASTEC was used.

  A gas generator is disposed in the desiccator 10 in a state where carbon dioxide is generated by a chemical reaction, the fan 11 is driven, and after 10 minutes, the detection tube 12 sucks the air in the desiccator 10 to generate carbon dioxide. Was measured.

(Comparative Example 5)
The same procedure as in Example 4 was performed except that 30 g of potassium carbonate that was not slightly water-soluble was used as the acid solid S.

  FIG. 5 shows changes over time in the amount of carbon dioxide generated in Example 4 (calcium carbonate + sodium polyacrylate) and Comparative Example 5 (potassium carbonate). The vertical axis in FIG. 5 indicates the carbon dioxide concentration (ppm), and the horizontal axis indicates the elapsed days.

  As a result of the experiment, a large amount of carbon dioxide was generated in both Example 4 and Comparative Example 5 for several days (less than 5 days) from the start of the experiment. This is considered to be because a large amount of neutralization reaction occurred because the acid aqueous solution L sucked up from the liquid absorbent core 3 permeates into the dry poorly water-soluble alkali solid S at the start of the experiment. After the hardly water-soluble alkali solid S is filled with the neutralized water, the acid aqueous solution L is supplied to the alkali solid S by the amount of the neutralized water evaporated from the alkali solid S, and the neutralization reaction is performed. As it occurs, the generation of carbon dioxide is thought to be slow. In order to moderate the initial gas generation, it is conceivable to make the alkali solid S in a wet state in advance, or to reduce the diameter of the liquid absorbent core 3 so as to moderate the initial liquid supply amount.

  Thereafter, in Example 4, the generated amount of carbon dioxide was stably maintained over 28 days, whereas in Comparative Example 5, a large amount of carbon dioxide was generated immediately after the start of the reaction, and then rapidly The amount of generated was reduced, and after 5 days, the result was lower than Example 4. In Comparative Example 5, the amount of carbon dioxide generated continued to decrease thereafter, and almost no carbon dioxide was detected before 15 days. In Example 4, compared to Comparative Example 5, it was possible to obtain a generation amount that resulted in a carbon dioxide concentration of about 3.75 times on the seventh day.

  Further, although not shown in FIG. 5, as another example, an experiment using an alkali solid S composed of only 30 g of poorly water-soluble calcium carbonate was performed. Also in this example, compared with Comparative Example 5, the amount of carbon dioxide generated could be stably maintained for a sufficiently long time. In addition, compared with this Example, Example 4 in which sodium polyacrylate was mixed as a water-absorbing polymer was able to efficiently maintain more stable generation of carbon dioxide.

  When solid substance S is a mixture containing a water-absorbing polymer as in Example 3 or Example 4, the reason why a more stable gas generation can be obtained is as follows. Since a water-soluble acid or alkali is used, it is considered that the solid S does not easily penetrate into the aqueous solution L as it is. For this reason, when the reaction between the acid in contact with the liquid-absorbing mat 4 and the alkali is completed, the poorly water-soluble component inside the solid material S cannot react properly, and the amount of gas generated is considered to decrease. . Therefore, it is presumed that by mixing the water-absorbing polymer with the solid material S, the aqueous solution L reaches the center of the solid material S and the reaction occurs without waste.

DESCRIPTION OF SYMBOLS 1 ... Gas generator 2 ... Container 3 ... Liquid absorption core (liquid absorption member) 4 ... Liquid absorption mat (liquid absorption member) 5 ... Non-woven bag (holding body) 6 ... Cover part 10 ... Desiccator 11 ... Fan 12 ... Detector tube L ... Aqueous solution S ... Solid matter

Claims (4)

A gas generator that generates a gas by a reaction between an alkali and an acid,
A vessel containing an aqueous solution containing alkali,
A solid matter disposed outside the container and containing a poorly water-soluble organic acid ;
A liquid-absorbing member disposed so as to protrude out of the container from the inside of the container, and for sucking out the aqueous solution in the container toward the solid matter outside the container;
The solid is a mixture of the organic acid and a water-absorbing polymer,
The gas generator in which the content ratio of the organic acid in the mixture is 60% or more and 90% or less . The gas generator according to claim 1, wherein the organic acid is at least one selected from the group consisting of fumaric acid and benzoic acid. A gas generation method for generating a gas by a reaction between an alkali and an acid,
Aqueous solution containing alkali is sucked out of the vessel of the container by the liquid absorbing member,
A gas is generated by the reaction between the aqueous solution and the solid substance outside the container,
The solid material includes a slightly water-soluble organic acid ,
The solid is a mixture of the organic acid and a water-absorbing polymer,
The gas generation method wherein the content ratio of the organic acid in the mixture is 60% or more and 90% or less . The gas generation method according to claim 3, wherein the organic acid is at least one selected from the group consisting of fumaric acid and benzoic acid.

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