JPH1015044A - Deodorant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to obtain an excellent deodorization effect on dimethyl sulfide by incorporating β type zeolite into a deodorant. SOLUTION: A deodorizing device comprises a nichrome wire 1 as a heating element and a catalyst coating layer 3 contg. the β type zeolite formed on the surface of this heating element. As a result, the air contg. malodorous components comes into contact with the catalyst coating layer 3 and absorbs the malodorous materials in the β type zeolite of the catalyst layer 3 when the nichrome wire 1 does not generate heat. The precious metal in the catalyst layer 3 is heated to its activation temp. and the malodorous components adsorbed thus far in the β type zeolite is made odorless and are released into the atmosphere when the nichrome wire generates heat. Simultaneously, the adsorption capability of the β type zeolite is regenerated. The β type zeolite has the excellent adsorbability to the dimethyl sulfide and, therefore, the βtype zeolite is capable of exhibiting the excellent deodorization effect on the dimethyl sulfide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorant used for heating, hot water supply, drying, cooking, refrigeration, air conditioning equipment and the like.

[0002]

2. Description of the Related Art Conventionally, amines, which are malodorous substances generated from foods in refrigerators, using adsorbents such as activated carbon, activated alumina, silica gel, A-type zeolite, Y-type zeolite, X-type zeolite and pentasil-type zeolite. The removal of chemicals, fatty acids, sulfur-containing organic compounds and the like has been performed.

[0003]

However, when the malodorous substance is dimethyl sulfide, which is a saury vegetable odor, activated alumina, silica gel, A-type zeolite, Y-type zeolite, X-type zeolite, and pentasil-type zeolite have a weak deodorizing effect. In addition, activated carbon has a problem that the deodorizing life is short because the adsorption capacity is small.

[0004] An object of the present invention is to provide a deodorant having a high deodorizing effect on dimethyl sulfide.

[0005]

In order to solve this problem, the present invention improves the deodorizing effect on dimethyl sulfide by including a β-type zeolite in the deodorant.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION
It is a deodorant containing β-type zeolite, and since β-type zeolite has a unique pore structure suitable for adsorption of dimethyl sulfide, which is a malodorous substance, it is possible to obtain an excellent deodorizing effect on dimethyl sulfide.

[0007] The invention according to claim 2 is a deodorant comprising β-type zeolite and a binder. By using the binder, the deodorant can be machined into a honeycomb, granular, plate, fin, or cylindrical shape. It can be processed as a deodorant having excellent mechanical strength, and a deodorant having a shape as required can be provided.

[0008] The invention according to claim 3 is a deodorant comprising β-type zeolite, a noble metal and copper oxide, and deodorizes methyl mercaptan, which is a malodorous substance, effectively by the catalytic action of the noble metal and copper oxide. By adsorbing dimethyl disulfide, which is a malodorous substance generated as a by-product when deodorizing, with β-type zeolite, generation of dimethyl disulfide can be suppressed. Further, the heat resistance of the deodorant can be improved by including both a noble metal and copper oxide.

According to a fourth aspect of the present invention, there is provided a deodorizing apparatus comprising a heating element and a catalyst coating layer formed on a surface of the heating element, the catalyst coating layer comprising at least β-type zeolite, a noble metal, copper oxide and an inorganic binder. If the heating element does not generate heat, the air containing the malodorous substance comes into contact with the catalyst coating layer, and the malodorous substance is adsorbed by the β-layer zeolite in the catalyst coating layer, or by the catalytic action of the noble metal and copper oxide. It is deodorized. When the heating element generates heat, the noble metal in the catalyst coating layer is heated to the activation temperature, and the malodorous substance adsorbed on the β-type zeolite is deodorized and released to the atmosphere. At the same time, it becomes possible to regenerate the adsorption capacity of β-zeolite. As a result, the deodorizing ability can be maintained for a long time.

[0010]

EXAMPLES The β-type zeolite used in this example is:
_{(M 2, M) O ·} Al 2 O 3 · nSiO 2 · mH 2 O (M
Is a hydrated silicate represented by monovalent and divalent metals),
It is a high silica zeolite having a three-dimensional pore structure of a 12-membered oxygen ring.

(Example 1) In order to examine the adsorption capacity of β-type zeolite to dimethyl sulfide, the following study was conducted.

A β-type zeolite, carboxymethylcellulose as a binder and water are kneaded at a weight ratio of 20: 3: 30, dried at 100 ° C. for 2 hours, calcined at 150 ° C. for 1 hour, and then reduced to 2-2.5 mm. It was pulverized to produce a deodorant A.

As a comparative example, a deodorant B was prepared by using activated carbon instead of β-zeolite in the deodorant A.

The deodorized substances A and B were subjected to a dimethyl sulfide adsorption capacity measurement test. The test for measuring the adsorption capacity of dimethyl sulfide was carried out in a glass tube having an inner diameter of 8 mm with 0.1 g of deodorant.
And 2 l of air containing 3 ppm of dimethyl sulfide
/ Min and flow continuously through the glass tube to pass the deodorant. Then, the dimethylsulfide concentration immediately after passing through the deodorant was measured intermittently until the adsorption reached saturation, whereby the adsorption capacity of the deodorant at 3 ppm of dimethylsulfide was calculated. The concentration was measured by gas chromatography. The results are shown in (Table 1).

[0015]

[Table 1]

As shown in Table 1, the deodorant containing β-type zeolite can have an excellent adsorption capacity for dimethyl sulfide. This is thought to be because β-type zeolite has excellent adsorption capacity for dimethyl sulfide.

(Example 2) In order to examine the relationship between the purification characteristics of dimethyl sulfide and the constituent components of the deodorant, the following examination was conducted.

Using a ball mill, 400 g of an aqueous colloidal silica solution containing 20 wt% of silica, 50 g of water and 320 g of β-zeolite were mixed to prepare a slurry c. The slurry was loaded on a cordierite honeycomb 400 cell having a size of 70 mm × 40 mm and a thickness of 10 mm by a dipping method, dried at 100 ° C. for 2 hours, and calcined at 500 ° C. for 1 hour to prepare a catalyst supporting honeycomb C having a catalyst film. .
The catalyst carrying amount is 4.0 g.

In the slurry c, slurries prepared by using A-type zeolite, Y-type zeolite, X-type zeolite, and pentasil-type zeolite instead of the β-type zeolite are referred to as slurries d, e, f, and g, respectively. Catalyst supporting honeycombs D, E, F and G were produced.

A dimethyl sulfide purification test was performed on the catalyst-carrying honeycombs C, D, E, F, and G. In the dimethyl sulfide purification test, a catalyst-supporting honeycomb was placed in a 250-liter cubic fluororesin container, dimethyl sulfide was injected into the container at a concentration of 3 ppm, and the air in the container was forcibly forced by a fan. Was passed through a honeycomb to examine the dimethylsulfide concentration after 60 minutes. The concentration was measured by gas chromatography. The results are shown in (Table 2).

[0021]

[Table 2]

As shown in Table 2, the use of β-type zeolite improves the ability to purify dimethyl sulfide. This is considered to be because β-type zeolite has a specific pore structure suitable for adsorption of dimethyl sulfide.

Example 3 In order to examine the relationship between the purification properties of methyl mercaptan and the constituent components of the deodorant, the following examination was conducted.

The aqueous solution of chloroplatinic acid and alumina were sufficiently mixed by using a ball mill, and then calcined and crushed at 500 ° C. to prepare alumina carrying platinum. Using a ball mill, 160 g of this platinum-supported alumina, 400 g of an aqueous colloidal silica solution containing 20 wt% of silica, 50 g of water, 160 g of β-zeolite, and 12 g of copper oxide were mixed to prepare a slurry h. The catalyst-supporting honeycomb H was produced by the method described above. The amount of catalyst carried was 4.0 g, and the platinum content was 100 mg.

Further, a platinum-supported alumina was prepared in which the amount of supported platinum was made half that of the platinum-supported alumina prepared at the time of preparing the slurry H. A slurry i was prepared by mixing 50 g of water using a ball mill, and a catalyst-supporting honeycomb I containing no β-type zeolite was prepared in the same manner as the catalyst-supporting honeycomb C. The platinum content is 100 mg.

The catalyst-supporting honeycombs C, H, and I were subjected to a methyl mercaptan purification test. In the methyl mercaptan purification test, methyl mercaptan was injected into a 250-liter cubic fluoroplastic container so that the concentration became 8 ppm, and the air in the container was forced to pass through the honeycomb by a fan, and after 30 minutes. Was examined for the methyl mercaptan concentration and the amount of dimethyl sulfide generated. The concentration was measured by gas chromatography. The results are shown in (Table 3).

[0027]

[Table 3]

As is clear from Table 3, a deodorant using a noble metal, copper oxide and silica can effectively remove methyl mercaptan, but generates a large amount of dimethyl disulfide. The deodorant using β-type zeolite and silica does not produce dimethyl disulfide, but has a weak deodorizing effect on methyl mercaptan. However, by including β-type zeolite, a noble metal, copper oxide, and silica, methyl mercaptan can be effectively removed and generation of dimethyl disulfide can be suppressed. This is thought to be because β-type zeolite has excellent adsorption ability even for dimethyl disulfide.

Example 4 In order to examine the relationship between the components of the deodorant and the heat resistance, the following examination was conducted.

A slurry j containing no copper oxide was prepared from the slurry h to prepare a catalyst supporting honeycomb J containing no copper oxide.

Further, a slurry k was prepared using alumina not containing platinum in the slurry h, and a catalyst supporting honeycomb K containing no platinum was produced.

The catalyst-supporting honeycombs H, J, and K were subjected to a methyl mercaptan purification test. In the methyl mercaptan purification test, methyl mercaptan was injected into a 250-liter cubic fluoroplastic container so that the concentration became 8 ppm, and the air in the container was forced to pass through the honeycomb by a fan, and after 30 minutes. Was examined for methyl mercaptan concentration. The concentration was measured by gas chromatography. After the adsorption test, the catalyst-supporting honeycomb
After performing a heat resistance test of heating in air at 0 ° C. for 168 hours,
After cooling to room temperature, the methyl mercaptan purification test was performed again to examine the heat resistance of the deodorized body. The results are shown in Table 4 below.

[0033]

[Table 4]

As is clear from Table 4, the deodorant to which only a noble metal or copper oxide is added has a reduced deodorizing property when heated at 700 ° C., but by adding both copper oxide and noble metal. In addition, the heat resistance of the deodorant can be improved.

(Example 5) The following examination was conducted in order to examine the regeneration effect of a deodorant by heating.

FIG. 1 shows an embodiment of the deodorizing apparatus of the present invention.
In FIG. 1, 1 is a coiled nichrome wire of 40Ω, 2 is a quartz tube covering the outer periphery of the nichrome wire 1, and 3 is a deodorant containing at least β-type zeolite formed on the surface of the quartz tube 2, a noble metal, copper oxide and an inorganic binder. Catalyst coating layer consisting of body, 4
Are insulating caps provided at both ends of the quartz tube 2.

The slurry h was prepared with an outer diameter of 10 mm and an inner diameter of 8 mm
240 mm at the center of the outer peripheral surface of the quartz tube 2 having a length of 348 mm
, And dried at 100 ° C. for 2 hours and baked at 500 ° C. for 1 hour. The catalyst coating weight was 1.0 g and the platinum content was 25 mg.

A heating element H having a catalyst coating layer 3 was prepared by mounting a coiled nichrome wire 1 of 40Ω in the quartz tube 2 and attaching insulating caps to both ends of the quartz tube 2.

The heating element was subjected to a dimethyl sulfide purification test. The test method is the same as the dimethyl sulfide purification test in Example 2. First, the heating element H is placed in a 250-liter cubic fluororesin container, dimethyl sulfide is injected into the container so that the concentration becomes 3 ppm, and the air in the container is forcibly removed by the fan. And the dimethyl sulfide concentration after 60 minutes was examined, and the result was regarded as the first test result. Next, after opening and replacing the inside of the container, the same experiment was performed, and the result was the second test result.
Further, after the experiment, the container was opened, and electricity was supplied for 10 minutes so that the temperature of the outer surface at the center of the heating element H became 350 ° C. After cooling the heating element H to near room temperature, a dimethylsulfide purification test was performed again, and the result was the first test after regeneration. The results are shown in (Table 5).

[0040]

[Table 5]

As shown in Table 5, the dimethyl sulfide adsorption ability is deteriorated in the second test result with respect to the first test result, but the adsorption ability is regenerated by regeneration. This is considered to be because the noble metal is activated by heating the catalyst coating layer, and the adsorption ability of β-type zeolite is regenerated by oxidative decomposition of dimethylsulfide adsorbed on β-type zeolite.

[0042]

As described above, according to the present invention, an excellent deodorizing effect on dimethyl sulfide can be obtained by including a β-type zeolite in the deodorant.

Also, by including a β-type zeolite and a binder in the deodorant, it becomes possible to process it into a honeycomb, granule, plate, fin, or cylindrical shape as a deodorant having excellent mechanical strength. Can be provided.

Further, by including β-type zeolite, a noble metal and copper oxide in the deodorant, methyl mercaptan can be effectively deodorized, and generation of dimethyl disulfide generated when deodorizing methyl mercaptan can be suppressed.
Further, the heat resistance of the deodorant can be improved.

Further, the deodorizing device is constituted by a heating element and a catalyst coating layer containing at least β-type zeolite, a noble metal, copper oxide and an inorganic binder formed on the surface of the heating element. Then, the air containing the malodorous substance comes into contact with the catalyst coating layer, and the malodorous substance is adsorbed by the β-type zeolite in the catalyst coating layer, or deodorized by the catalytic action of the noble metal and copper oxide. When the heating element generates heat, the noble metal in the catalyst coating layer is heated to the activation temperature, and the malodorous substance adsorbed on the β-type zeolite is deodorized and released to the atmosphere. At the same time, it is possible to regenerate the adsorption capacity of β-type zeolite, and it is possible to maintain the deodorizing capacity for a long period of time.

[Brief description of the drawings]

FIG. 1 is a cutaway front view of a deodorizing device according to a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nichrome wire 2 Quartz tube 3 Catalyst coating layer 4 Insulation cap

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masami Matsunaga 4-2-5 Takaidahondori, Higashiosaka City, Osaka Inside Matsushita Refrigeration Co., Ltd.

Claims (4)

[Claims] 1. A deodorant comprising β-type zeolite. 2. The deodorant according to claim 1, further comprising a binder. 3. The deodorant according to claim 1, comprising a noble metal and copper oxide. 4. A deodorizing apparatus comprising a heating element and a catalyst coating layer formed on the surface of the heating element and formed of a deodorizing body containing at least β-type zeolite, a noble metal, copper oxide and an inorganic binder.