JPH0686804A - Air cleaning substance and its manufacture - Google Patents

Abstract

PURPOSE:To remove acetaldehyde in main component producing an odor of tobacco by making a carrier body of a silica gel molding having a water resisting property and allowing the carrier body to carry fine grain metal iron. CONSTITUTION:Silica gel having a water resisting property is immersed in aqueous solution dissolving ferrous sulfate and hydrazine with mutually nearly equal mol and then dried, so that the ferrous sulfate of metal salt is reduced to separate metal iron in the liquid phase. Thus, metal iron grains carried on the surface of the silica gel as the carrier body having water resisting property or on the surface fine cavities of the water resisting silica gel molding become fine grains. The CH3CHO removing performance of such constructed air cleaning substance is so excellent that the performance is displayed for a long time. For example, for a deodorizing test apparatus, a circulating fan 2 having a capacity of blasting 400 liters/min can be provided in an enclosed receptacle having a capacity of 40 liters. The filter-like air cleaning substance 3 as a sample, a gas inlet 4 and a gas sample sampling port 5 are provided to circulate gas in the direction of the arrow 6 to test the CH3CHO removing performance of the air cleaning substance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air-purified product for removing CH ₃ CHO (acetaldehyde), which is a main component of tobacco odor, and a method for producing the same. The air-purified product of the present invention can be used, for example, as a household deodorant and a vehicle deodorant.

[0002]

As a method for treating malodorous gas in the air, for example, adsorption method using activated carbon, masking method using other fragrance, chemical removal method for chemically reacting odor, etc., or removal of discomfort is performed. Has been done. But,
The adsorption method using activated carbon has a problem that the deodorizing performance deteriorates in a short period of time. The masking method using other fragrances may not be a fundamental solution because the fragrance may cause new discomfort. As a chemical method of causing a chemical reaction, 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. That is, it is difficult to control the amount of the chemical substance that reacts with the malodorous gas, so that an unnecessary chemical substance is generated, and it is hard to be a fundamental solution.

CH ₃ C, which is the main component of tobacco odor,
For removal of HO, it is difficult to remove even with activated carbon.
As in 6-53744, aniline having high chemical reactivity is impregnated on activated carbon to improve the removal performance.
Various measures have been taken such as chemical reaction with phenylhydrazine to remove it like No. 95319.

[0004]

According to the findings of the present inventors, there are disadvantages such as a bad odor of the above-mentioned chemically reactive substance itself, a difficulty in maintaining the activity of the chemical substance and a short life. It was hard to find a fundamental solution. In view of the above problems, the present invention is particularly applicable to CH ₃ CH which is a main component of tobacco odor.
It is an object of the present invention to provide a method for producing an air-purified product that has excellent O removal performance and exhibits that performance over a long period of time in a simple process.

[0005]

Means for Solving the Problems The present invention is to solve the above problems and is characterized in that a molded body of water-resistant silica gel is used as a carrier, and fine metal iron particles are carried on the carrier. It is a compound. Further, it is a method for producing an air-purified product characterized by precipitating metallic iron on the surface of the silica gel by immersing the water-resistant silica gel in an aqueous solution in which ferrous sulfate and hydrazine are dissolved in approximately equimolar and then drying. .

[0006]

The present inventor has conducted research on a catalyst composition that can be easily handled by supporting various substances including the above-mentioned activated carbon on a specific substance that does not cause a bad odor. As a result, it removes itself from CH ₃ CHO.
It has been found that a water-resistant silica gel having no performance is exposed to an aqueous solution in which ferrous sulfate and hydrazine are dissolved in approximately equimolar amounts, and then dried to exhibit CH ₃ CHO removal performance.

That is, by immersing the water-resistant silica gel in an aqueous solution in which ferrous sulfate and hydrazine are dissolved in approximately equimolar amounts and then drying the ferrous sulfate, which is a metal salt, is subjected to liquid-phase reduction to produce metallic iron. To deposit. As a result, the particles of metallic iron carried on the surface of the water-resistant silica gel, which is the carrier, or on the surfaces of the insides of the fine voids of the molded body of water-resistant silica gel become fine particles.
The H ₃ CHO performance is excellent, and the performance is exhibited for a long period of time. Hereinafter, the present invention will be specifically described based on Examples.

[0008]

[Examples] As shown in Table 1, a molded body obtained by molding water-resistant silica gel into pellets having a diameter of 5 mm was immersed in an aqueous solution containing ferrous sulfate and hydrazine under various conditions, and kept in the air for 1 month. CH ₃ CHO after left to dry naturally
The deodorizing performance was examined. NaOH was used to adjust the pH of the aqueous solution.

As shown in FIG. 1, in the deodorization test apparatus, a circulation fan 2 having a blowing capacity of 400 liters / minute is installed in a closed vessel 1 of 40 liters. In the figure, 3 is a filter-like air purifying material to be a sample, 4 is a gas introduction port, 5 is a gas sample collection port, and the gas is circulated in the direction of arrow 6. C
The initial concentration of H ₃ CHO was 20 ppm, the residual concentration after 30 minutes was measured, and the concentration ratio of the removed gas component was determined.

[0010]

[Table 1]

Table 1 shows the evaluation results of the deodorizing performance. For comparison, a deodorizing performance test of untreated water-resistant silica gel was conducted, but no deodorizing effect was found. As a result, when treated with an aqueous solution of ferrous sulfate and human lazine dissolved in water-resistant silica gel in approximately equimolar amounts, C
A composition having extremely excellent H ₃ CHO performance was obtained.

[0012]

Industrial Applicability According to the present invention, a highly purified air-purified product can be obtained by a simple production method with respect to CH ₃ CHO, which has no deodorant having a satisfactory performance. That is, conventional de-CH ₃ CH
By loading fine particulate metal iron on water-resistant silica gel having no O performance, an air-purified product with high deCH ₃ CHO performance can be obtained.

[Brief description of drawings]

FIG. 1 is an explanatory view showing the structure of a test device for evaluating deodorizing performance.

Claims (2)

[Claims] 1. An air-purified product, characterized in that a molded body of water-resistant silica gel is used as a carrier, and fine metal iron particles are carried on the carrier. 2. An air-purified product characterized by precipitating metallic iron on the surface of the silica gel by immersing the water-resistant silica gel in an aqueous solution in which ferrous sulfate and hydrazine are dissolved in approximately equimolar amounts, and then drying. Production method.