JPH0596158A - Method for producing composition having air cleaning power - Google Patents

Abstract

(57) [Summary] [Object] The present invention provides a method for producing an air purification material for purifying contaminated air containing malodorous gases represented by NH ₃ and H ₂ S. [Composition] Iron or iron and iron oxide or iron and iron oxide and iron compound are reacted with tannic acid or gallic acid or a mixture thereof in an aqueous solution state to adjust the pH to 5 or more, and then hydrogen sulfide gas is blown into the aqueous solution. React. Iron content is 0.05 to 2 mol / l, and the amount of tannic acid or gallic acid calculated in terms of gallic acid is 0.05 to 2 mol / l.
Of water, the temperature of water is raised to 80 ° C. or higher to react, and after cooling to near room temperature, the amount of hydrogen sulfide gas blown into the aqueous solution is a molar ratio as the amount of sulfur to iron. It is set to 0.005 to 0.1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air purification material for purifying polluted air containing offensive odor gases such as NH ₃ and H ₂ S. The air cleaning material of the present invention can be used, for example, as a household deodorant.

[0002]

2. Description of the Related Art A malodorous gas in the air is removed by an adsorption method using activated carbon, a masking method using another fragrance, or a chemical method for chemically reacting an odor, or reducing unpleasant sensation. ing.

However, the adsorption method using activated carbon has a problem that the deodorizing performance deteriorates in a short period of time, and the masking method using other fragrances may give a new discomfort to the fragrance. I won't.

As a chemical method of chemically reacting, for example, there is a method of oxidizing and decomposing a malodorous gas with ozone, but excessive ozone is harmful to the human body and causes new harm. In other words, it is difficult to control the amount of chemical substances that react with the malodorous gas, so unnecessary chemical substances are generated, and it is difficult to make a fundamental solution.

As a technique for solving these problems, the Journal of the Textile Society of Japan (Fiber and Industry), Vol. 42, No. 12 (1
986), P18-26, it is stated that a complex compound obtained by reacting a ferrous compound and ascorbic acid in an aqueous solution has a deodorizing power for nitrogen compound-based odorous gas.

However, the inventors of the present invention have found that this complex compound has a problem that it has a weak deodorizing power for sulfur compound type odorous gas. According to the findings of the present inventors, there is also a problem that the deodorizing power of this complex compound deteriorates in a relatively short period of time.

The inventors of the present invention have invented a composition in which a reaction product obtained by contacting a metal such as iron or manganese with ascorbic acid or the like is allowed to coexist with unreacted iron or manganese. A patent application was filed under No. 1-2780776. This composition can be manufactured at low cost, and the deterioration of the air cleaning power is extremely small, which solves the problems of the prior art.

According to the research conducted by the present inventors, NH ₃ and (C
The deodorizing performance of basic gas such as H ₃ ) ₃ N is very well adsorbed on a metal complex which is a reaction product of a polybasic acid and a metal.
The adsorption power of H ₃ SH gas is weak. One solution is
This is a method of disposing a solid base as described in Japanese Patent Application No. 63-273195 by the present inventors.

However, in the subsequent research, it was found that the substances having a strong adsorptive power for acidic gas such as H ₂ S are metal hydroxides and metal oxides produced by dissolving metal in an aqueous solution. Furthermore, they have also found that it is necessary to form a state in which a metal and a hydroxide or a metal oxide coexist in order to effectively generate a hydroxide and continue the effect stably for a long period of time.

The reason why the de-CH ₃ SH performance improves as the de-H ₂ S performance improves is considered to be that H of the --SH group has the same properties as H ₂ S. Therefore, it can be inferred that it is effective to effectively generate the metal hydroxide. However, studies by the present inventors have revealed that good de-H ₂ S performance is not a sufficient condition for good de-CH ₃ SH performance.

For example, iron and L-ascorbic acid aqueous solution are brought into contact with each other in the air, and the complex salt produced and the coexisting substance of iron are mixed in an amount of 150.
The reaction product heat-treated at 24 ° C for 24 hours was extremely free of H ₂ S.
Good performance, but slightly inferior CH ₃ SH performance.

As a result of investigating various countermeasures for improving the de-CH ₃ SH performance, iron hydroxide, ferric oxide, Magnetite is generated, and a composition having extremely excellent dehydrogenation of H ₂ S is generated. However, when hydrogen sulfide is adsorbed on it, it is extremely deCH ₃ S depleted as compared with the composition before adsorbing hydrogen sulfide.
It was found that the composition changed to an excellent H performance.

De-CH generated by this hydrogen sulfide adsorption
₃ As a result of detailed investigation of the composition having excellent SH performance,
We have found that iron sulfide has a major effect.

Further, it was also found that similar results can be obtained by reacting a metal having a high sulfur content in advance with an aqueous solution of an acid in the air. It could be solved by the method described in 3-16815.

[0015]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
It is an object of the present invention to further extensively study the composition of No. -16815 to provide a material having an air cleaning power in a new process that is simpler and safer. In particular, it is desired to provide a manufacturing process in which H ₂ S is not generated in the manufacturing process and an operator is not concerned with gas poisoning.

[0016]

According to the present invention, (1) iron or iron and iron oxide or iron and iron oxide and an iron compound are reacted with tannic acid or gallic acid or a mixture thereof in an aqueous solution state to have a pH of 5 or more. After that, the method for producing a composition having an air cleaning power is characterized in that hydrogen sulfide gas is blown into the aqueous solution to react.

The iron content of (2) (1) is 0.05 to 2
mol / l and the amount of tannic acid or gallic acid calculated in terms of gallic acid are mixed with water at a ratio of 0.05 to 2 mol / l, the temperature of water is raised to 80 ° C. or higher to react, and the temperature is kept around room temperature. A method for producing a composition having an air cleaning power, characterized in that the amount of hydrogen sulfide gas blown into the aqueous solution after cooling is 0.005 to 0.1 in terms of the amount of sulfur to iron Is.

Further, (3) (1) H ₂ S gas is 10 p
Air diluted below pm or concentrated H ₂ S
The gas is enclosed in a container whose volume can be freely changed while maintaining the atmospheric pressure, and the outlet of the container is iron or iron and iron oxide or iron and iron oxide and iron compounds and tannic acid or gallic acid or a mixture thereof in an aqueous state. It is a method for producing a composition having an air cleaning power, which comprises reacting in a structure of being connected to an aqueous solution having a pH of 5 or more.

Further, the composition of (4) (1) contains Fe, N
A method for producing a composition having an air cleaning power, which is a composition coexisting with one or more metals selected from i, Cr, Mn, Co, Cu and Zn or a sulfide thereof.

[0020]

[Function] The concentration of H ₂ S gas that causes no health hazard is 10
It is said to be below ppm. Therefore, if used by diluting 10ppm or less in advance air H ₂ S gas, event H ₂ S
It is safe even if gas flows out.

However, although it is safe to use a low concentration gas, the volume of the gas used increases by that much, and the efficiency is not good. When a 100% H ₂ S gas or a high concentration H ₂ S gas close to the H ₂ S gas is used, it is necessary to devise an extra gas that is not absorbed by iron oxide to leak out.

More specifically, the reaction may be advanced using an apparatus having the function of the structure shown in FIG. That is, iron or iron and iron oxide or iron and iron oxide and iron compound are reacted with tannic acid or gallic acid or a mixture thereof in an aqueous solution state to prepare an aqueous solution having a pH of 5 or more.

The H ₂ S gas is placed in a container 3 such as a Tedlar pack 3 equipped with a valve 4 and an inlet / outlet pipe 5, the shape of which changes while maintaining the atmospheric pressure according to the volume of the content gas. If the amount of H ₂ S gas is too large, the risk in case of outflow increases, and if it is too small, the amount of FeS produced is small and the deodorizing performance deteriorates. It is preferably adjusted to about 0.05.

An inlet / outlet pipe 5 for the Tedlar pack 3 in the aqueous solution 1.
When the valve 4 is opened while immersing the H ₂ S and stirring the aqueous solution, the H ₂ S gas reacts with the iron oxide in the aqueous solution and is gradually consumed. When the target amount is absorbed, the valve 4 is closed and the work is finished.

The amount of iron, tannic acid or gallic acid to achieve these purposes is 0.05 to 2 mo, respectively.
1 / l. If the blending amount is too small, the effect is small, and if the blending amount is too large, the viscosity of the solution becomes too high and the manufacturing work becomes difficult, which is not practical.

A specific method for simultaneously achieving appropriate work efficiency and performance is a method in which substantially equimolar iron and an aqueous solution of an organic acid are heated in a hot water state for reaction, and then hydrogen sulfide is adsorbed.

By heating iron and an aqueous solution of an organic acid in a hot water state to react with each other, not only a complex of iron and an organic acid is produced, but also iron oxide which reacts extremely rapidly with H ₂ S gas is produced. H
₂ S gas reacts with iron oxide to produce iron sulfide and water.
₂ S gas does not escape into the atmosphere. The unreacted excess H ₂ S gas remaining in the Tedlar pack does not escape to the atmosphere because the outlet is sealed with the aqueous solution.

Even when iron and an aqueous solution of an organic acid are mixed and kept at room temperature for a long period of time, iron oxide and magnetite are produced to some extent, and therefore, an effect which is about a fraction of that in the case of reacting in hot water can be obtained. Since the amount of iron oxide produced in (1) is small and not perfect, it is preferable to raise the temperature of the aqueous solution as much as possible to react.

The substances having the air cleaning power produced in this manner are Fe, Ni, Cr, Mn, Co, Cu and Z.
By coexisting with a metal such as n, there is an effect that a life period for exhibiting deodorizing performance is extended due to an effect of forming a new metal oxide with the passage of time.

Next, examples of the present invention will be described.

[0031]

【Example】

[0032]

Example 1 An aqueous solution containing 1.2 mol / l of carbonyl iron powder and 1.2 mol / l of tannic acid in terms of gallic acid was heated to 100 ° C., reacted with stirring for 10 minutes, and cooled to room temperature. 90% concentration in 1 liter of the aqueous solution
The deodorizing agent solution was produced by absorbing 100 cc of H ₂ S gas.

A urethane foam having a coarseness of 20 PPI was dipped in the aqueous solution to apply the reaction product and dried at room temperature for 24 hours to produce a deodorizing filter. The deodorizing filter had a size of about 80 mm × 100 mm × 12 mm and a weight of about 15 g.

The deodorizing performance was evaluated using a test apparatus having the structure shown in FIG. The internal volume of the test apparatus was 40 l, and the air volume of the circulation fan was about 400 l / min.

First, the de-CH ₃ SH performance is evaluated first,
Subsequently, the NH ₃ removal performance and the H ₂ S removal performance were evaluated. The evaluation results are shown in Table 1.

[0036]

Example 2 A porous iron body produced by applying fine 10 μ-under powder of pig iron to urethane foam having a coarseness of 20 PPI and firing in a non-oxidizing atmosphere at 1150 ° C. for 2 hours was the same as in Example 1. Produced iron powder, tannic acid, H ₂ S
A deodorizing filter was manufactured by immersing in a reaction aqueous solution of gas and leaving it for 2 hours at room temperature to dry. The resulting deodorizing filter had a size of about 80 mm × 90 mm × 10 mm and a weight of about 40 g.

The deodorizing performance was evaluated using a test apparatus having the structure shown in FIG. The internal volume of the test apparatus was 40 l, and the air volume of the circulation fan was about 400 l / min. First, the de-CH ₃ SH performance is evaluated first, followed by the de-NH ₃ performance and de-H treatment.
₂ S performance was evaluated. The evaluation results are shown in Table 2.

[0038]

Example 3 Similar to Example 2, 10% sulfur and 20%
A ferroalloy porous body containing 10% Mn was produced. Using the alloyed iron porous body, it was immersed in a reaction aqueous solution of iron powder, tannic acid, and H ₂ S gas produced in the same manner as in Example 1, and allowed to stand at room temperature for 2 weeks for drying to produce a deodorizing filter.
The size of the finished deodorizing filter is about 85 mm x 9
It was 5 mm × 10 mm and weighed about 50 g.

The deodorizing performance was evaluated using a test apparatus having the structure shown in FIG. The internal volume of the test apparatus was 40 l, and the air volume of the circulation fan was about 400 l / min. First, the de-CH ₃ SH performance is evaluated first, followed by the de-NH ₃ performance and de-H treatment.
₂ S performance was evaluated. The evaluation results are shown in Table 3.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

[0043]

INDUSTRIAL APPLICABILITY According to the present invention, NH ₃ removal performance and H ₂ S removal
Performance, deoxidized (CH ₃ ) ₃ N performance is good, and further de-CH ₃ S
An air-purified product with excellent H performance can be manufactured safely and efficiently.

[Brief description of drawings]

FIG. 1 is an explanatory view showing the structure of an apparatus for adsorbing and reacting H ₂ S gas with an aqueous solution according to the present invention.

FIG. 2 is an explanatory view showing the structure of a test device for evaluating deodorizing performance.

[Explanation of symbols] 1 aqueous solution 2 stirrer 3 Tedlar pack (container) 4 valve 5 inlet / outlet pipe 6 closed container 7 circulation fan 8 deodorizing filter 9 gas inlet port 10 gas sample collection port 11 gas circulation direction

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B01D 53/34 131 6953-4D C09K 3/00 S 9049-4H

Claims (4)

[Claims] 1. After reacting iron or iron and iron oxide or iron and iron oxide and iron compound with tannic acid or gallic acid or a mixture thereof in an aqueous solution to adjust the pH to 5 or more,
A method for producing a composition having an air cleaning power, which comprises reacting by blowing hydrogen sulfide gas into the aqueous solution. 2. The iron content of claim 1 is 0.05 to 2 mol /
1, and the amount of tannic acid or gallic acid calculated in terms of gallic acid were mixed with water at a ratio of 0.05 to 2 mol / l, the temperature of water was raised to 80 ° C. or higher to react, and cooled to around room temperature. A method for producing a composition having an air cleaning power, characterized in that the amount of hydrogen sulfide gas to be added later to the aqueous solution is 0.005 to 0.1 in terms of a molar ratio as a sulfur content to an iron content. 3. The H ₂ S gas of claim 1 is diluted with air to 10 ppm or less, or the concentrated H ₂ S gas is enclosed in a container whose volume can be freely changed while maintaining atmospheric pressure,
When the outlet of the container is made to react with iron or iron and iron oxide or iron and iron oxide and iron compound and tannic acid or gallic acid or a mixture thereof in an aqueous solution state and connected to an aqueous solution whose pH is 5 or more, the reaction is performed. A method for producing a composition having a characteristic air cleaning power. 4. The composition of claim 1 comprising Fe, Ni, Cr,
A method for producing a composition having air cleaning power, which is a composition coexisting with one or more metals selected from Mn, Co, Cu and Zn or a sulfide thereof.