JPH0549849A - Method for deodorization and treating agent therefor - Google Patents

Abstract

PURPOSE:To provide a method for effective deodorization for various malodors from raw sewage, refrigerator, toilet, etc., of ordinary life to general manufacturing factories, cattle houses, sewage treating facilities, etc. CONSTITUTION:This method for deodorization of malodor and the treating agent feature in that the treating agent contains peroxides and that this treating agent is used for deodorization treatment of gas containing malodors such as hydrogen sulfide and ammonia in the presence of ozone. By using the treating agent containing peroxides, the method for ozone deodorization excellent in deodorization performance and treating performance for unreacted ozone can be obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for deodorizing a gas containing a malodorous component using ozone, and a treating agent used therefor.

[0002]

BACKGROUND OF THE INVENTION There are various sources of offensive odors, from food waste, refrigerators, toilets, etc. in daily life to general production plants, livestock farms, sewage treatment, etc. Also, there are many places in hospitals, hotels, restaurants, etc. that have a unique odor, if not stinking. Ammonia, mercaptans, sulfides, amines, aldehydes, etc. are attracting attention as the causative substances of these malodors or peculiar odors (hereinafter collectively referred to as "malodors"), but they are actually more complicated. And is not limited to these substances. In recent years, as the demand for a technique for removing these malodors has increased, research on the malodor removing technique has become popular, and various methods have been proposed, for example, as follows.

[0003] A masking method for eliminating an offensive odor by emitting an aromatic substance which is stronger than an offensive odor, an adsorption method for adsorbing an offensive odor causing substance by using an activated carbon or other adsorbent, and an acid or alkali neutralizing the offensive odor causing substance. And an acid deodorizing method, in which ozone is added to the odor-causing substance to oxidize and decompose it.

[0004]

However, each of the above-mentioned methods has serious drawbacks. For example, the masking method is not an essential method. The adsorption method has a limited adsorption amount due to the saturated adsorption amount and cannot cope with a strong malodor. Acid and alkali neutralization methods are limited to substances that can be neutralized, and the odors that can be dealt with are limited.

Although the ozone deodorization method does not have the above-mentioned problems, unreacted ozone is not obtained because the odor-causing substance is not sufficiently removed by oxidative decomposition and ozone is extremely harmful even at a low concentration. There is a problem in that it is necessary to remove the gas after the deodorization treatment and exhaust the gas.

[0006]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have conducted various studies on a treating agent to be subjected to the ozone deodorizing method (hereinafter referred to as “ozone deodorizing catalyst”), and as a result, The following inventions have been reached.

That is, the present invention provides: (1) a deodorizing method characterized by using an ozone deodorizing catalyst containing a peroxide when deodorizing a gas containing a malodorous component in the presence of ozone; The deodorizing method according to (1) above, wherein the oxide is at least one selected from barium peroxide, calcium peroxide, zinc peroxide, sodium percarbonate, and sodium perborate, and (3) the ozone deodorizing catalyst contains activated carbon. The deodorizing method according to (1) or (2) above, (4) an ozone deodorizing catalyst containing a peroxide for deodorizing a gas containing a malodorous component in the presence of ozone, (5) peroxide Is barium peroxide, calcium peroxide, zinc peroxide,
The present invention relates to the ozone deodorizing catalyst according to (4), which is at least one selected from sodium percarbonate and sodium perborate, and (6) the ozone deodorizing catalyst according to (4) or (5), which contains activated carbon. INDUSTRIAL APPLICABILITY The ozone deodorizing catalyst of the present invention is excellent in deodorizing treatment ability for an offensive odor-causing substance and also excellent in unreacted ozone treating ability, and can perform effective deodorization.

The present invention will be described in detail below. The peroxide used in the present invention can be widely selected from hydrogen peroxide, inorganic peroxides and organic peroxides, but preferred are sodium peroxide, calcium peroxide, barium peroxide and zinc peroxide. Inorganic peroxides such as sodium percarbonate, sodium perborate, perchloric acid and its salts (sodium salt, etc.), persulfuric acid and its salts (sodium salt, etc.), perphosphoric acid and its salts (potassium salt, etc.) , Organic peracids such as peracetic acid and benzoyl peroxide. Particularly preferred peroxides include one or more compounds selected from calcium peroxide, barium peroxide, zinc peroxide, sodium percarbonate and sodium perborate.

The ozone deodorizing catalyst of the present invention preferably contains a commonly used porous carrier in order to improve the performance. Preferred carriers include silica, alumina, silica-alumina, silica-magnesia, natural zeolite, synthetic zeolite, diatomaceous earth, activated carbon, Kanuma soil, clay minerals and inorganic fibers, but are not particularly limited to these. However, any commonly used carrier can be used.

Among them, particularly preferred is activated carbon. The type of activated carbon is not particularly limited, but the specific surface area is 6
It is preferable to use one having a high specific surface area of 00 m ² / g or more. When activated carbon is used as the carrier, both the ability to treat the offensive odor-causing substance and the ability to treat surplus ozone are improved, and the carrier can be used at a lower temperature. In many cases, the ozone deodorizing catalyst is usually molded and used, and in consideration of practicality such as moldability and hardness, it is more preferable to use the activated carbon as a carrier together with other carriers. The proportion of the carrier in the ozone deodorizing catalyst is arbitrary, but is preferably 1 to 99% by weight, particularly preferably 10 to 90% by weight. When activated carbon is used together with other carriers, the proportion of activated carbon in the carrier is preferably 5 to 90% by weight, particularly preferably 10 to 70% by weight.

The ozone deodorizing catalyst of the present invention can be obtained by mixing the respective raw materials, but it is often obtained as a powder depending on the form of the raw materials used, and the powder may be used as it is, but there are restrictions on use. In some cases, it can be molded into various shapes by a known method, and the shape is not particularly limited. For example, it can be used after being formed into a granular shape, a pellet shape, a honeycomb shape, a plate shape, or a cylindrical shape.
Generally, when the powder is molded into pellets or the like, a binder (binder) is often used to facilitate the molding, but the ozone deodorizing catalyst of the present invention is no exception,
It is possible to mold using a commonly used binder.

Preferred binders are bentonite, colloidal silica, white clay, kaolin, inorganic substances such as water glass, sodium alginate, glucose, dextrin, hydroxypropyl cellulose, carboxymethyl cellulose sodium salt, and glue, polyvinyl alcohol, polyvinylpyrrolidinone, etc. Examples of the organic polymer-based binders include, but are not limited to, any commonly used binders can be used.

The raw materials used in producing the ozone deodorizing catalyst of the present invention are not particularly limited, and any of the normally available raw materials can be used. Examples of the malodor causing substance (malodor component) to be deodorized by the method of the present invention include, for example, hydrogen sulfide, methyl mercaptan, ammonia, trimethylamine, methyl sulfide, methyl disulfide, acetaldehyde, styrene, propionic acid, normal valeric acid, isokichi Herbate,
Examples thereof include normal butyric acid, formalin, acrolein, acetic acid, methylamine, dimethylamine and the like.

The amount of ozone to be made to coexist with the offensive odor-causing substance is
The amount is preferably 0.1 to 100 times mol, more preferably 0.5 to 10 times mol of the total amount of the malodor causing substance, although it varies depending on the kind and concentration of the bad smell causing substance. It is necessary to sufficiently mix the gas containing the malodorous component with ozone before the malodorous substance contacts the ozone deodorizing catalyst, and the mixing can be performed by a known method.

The mixed gas of the gas containing a malodorous component and ozone is brought into contact with the ozone deodorizing catalyst, but the temperature at that time is not particularly limited, and for example, a wide temperature range of −10 ° C. to 150 ° C. is possible. is there. In particular, deodorization and removal of unreacted ozone can be performed even at a low temperature of 0 ° C to 50 ° C.

[0016]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The ozone removal rate and deodorization rate in the examples were calculated by the following equations. Ozone removal rate (%) = (1-catalyst layer outlet ozone concentration / catalyst layer inlet ozone concentration)
× 100 Deodorization rate (%) = (1-concentration of substance causing offensive odor at catalyst layer / concentration of substance causing offensive odor at catalyst layer) × 100

Example 1 400 g of 50% calcium peroxide, synthetic zeolite 80
A small amount of water was added to 0 g and 100 g of carboxymethyl cellulose sodium salt as a binder, and the mixture was extruded with a die having a hole diameter of 4 mm by an extrusion molding machine. The extruded udon-like ozone deodorizing catalyst is immediately cut by a cutter at 3 to 10 m.
It was cut into m length and dried at 110 ° C. to obtain a column-shaped ozone deodorizing catalyst. 100 ml of the obtained ozone deodorizing catalyst was filled in a glass reaction tube and kept at 50 ° C.

Air containing 30 ppm of hydrogen sulfide and 50 ppm of ozone was introduced into the ozone deodorizing catalyst at a flow rate of 5 liters per minute after previously humidifying by passing through a water seal. The outlet gas from the ozone deodorizing catalyst layer was introduced into an ozone monitor and an odor-causing substance analyzer (gas chromatograph) to quantify ozone and hydrogen sulfide concentrations. The ozone removal rate and deodorization rate after the continuous operation for 24 hours were as follows. Ozone removal rate = 100% Hydrogen sulfide deodorization rate = 95%

Example 2 In the same manner as in Example 1, except that 400 g of zinc peroxide was used in place of 50% calcium peroxide in the same manner as in Example 1 except that the ozone deodorizing catalyst prepared in the same manner as in Example 1 was used. I went. The results after 24 hours of continuous operation were as follows. Ozone removal rate = 100% Hydrogen sulfide deodorization rate = 94%

Example 3 In Example 1, the same test as in Example 1 was carried out by using 30 ppm of methyl mercaptan instead of hydrogen sulfide as the offensive odor-causing substance. The results after 24 hours of continuous operation were as follows. Ozone removal rate = 100% Methyl mercaptan deodorization rate = 98%

Example 4 250 g of 80% barium peroxide, activated carbon (specific surface area 96
0 m ² / g) 500 g, natural zeolite 450 g and carboxymethylcellulose sodium salt 10 as a binder
A cylindrical ozone deodorizing catalyst was obtained in the same manner as in Example 1 using 0 g. A glass tube was filled with 100 ml of the obtained ozone deodorizing catalyst and kept at 30 ° C.

Air containing 20 ppm of ammonia and 70 ppm of ozone was introduced into the ozone deodorization catalyst at a flow rate of 4 liters per minute after previously humidifying by passing through a water seal. The outlet gas from the ozone deodorizing catalyst layer was subjected to quantitative determination of ozone and ammonia gas concentrations with an ozone monitor and a detector tube. The ozone removal rate and deodorization rate after continuous operation for 3 hours were as follows. Ozone removal rate = 100% Ammonia deodorization rate = 90%

Example 5 In order to examine the effect of activated carbon, an ozone deodorizing catalyst was prepared in the same manner as in Example 1 except that half of the synthetic zeolite was replaced with activated carbon (specific surface area 960 m ² / g). Using this, a test was conducted in the same manner as in Example 1. As a result, the ozone removal rate and hydrogen sulfide deodorization rate after continuous operation for 24 hours were both 10
It was 0%.

Example 6 A glass tube was filled with 60 ml of the ozone deodorizing catalyst of Example 5, and the temperature of the ozone deodorizing catalyst was maintained at 30 ° C. After passing through a water seal and humidifying in advance, hydrogen sulfide 30ppm, and 50pp
6 m / min of air containing ozone of 6 m / min.
It was introduced at a flow rate of 1 liter and tested. The ozone removal rate and the hydrogen sulfide deodorization rate after the continuous operation for 24 hours were as follows. Ozone removal rate = 100% Hydrogen sulfide deodorization rate = 98%

Example 7 A glass tube was filled with 60 ml of the ozone deodorizing catalyst of Example 5, and the temperature of the ozone deodorizing catalyst was maintained at 30 ° C. After passing through a water seal and humidifying in advance, hydrogen sulfide 15ppm, and 50pp
6 m / min of air containing ozone of 6 m / min.
It was introduced at a flow rate of 1 liter and tested. The ozone removal rate and the hydrogen sulfide deodorization rate after the continuous operation for 24 hours were as follows. Ozone removal rate = 100% Hydrogen sulfide deodorization rate = 100%

Example 8 200 g of sodium perborate, activated carbon (specific surface area 960
m ² / g) 800 g, silica alumina 450 g, silica aerosil 200 g and carboxymethyl cellulose sodium salt 80 g as a binder were used to obtain a cylindrical ozone deodorizing catalyst in the same manner as in Example 1. A test was conducted in the same manner as in Example 6 using 60 ml of the obtained ozone deodorizing catalyst. The results after 24 hours of continuous operation were as follows. Ozone removal rate = 100% Hydrogen sulfide deodorization rate = 96%

Example 9 A test was conducted in the same manner as in Example 8 except that 200 g of sodium percarbonate was used in place of sodium perborate in Example 8. The results after 24 hours of continuous operation were as follows. Ozone removal rate = 100% Hydrogen sulfide deodorization rate = 95%

Comparative Example 1 In order to see the effect of peroxide, 1000 g of the synthetic zeolite used in Example 1 and 100 g of carboxymethyl cellulose sodium salt as a binder were used, and calcium peroxide was not used. A cylindrical agent was obtained by molding in the same manner as in. A test was conducted in the same manner as in Example 1 using 100 ml of the obtained agent. The results after 24 hours of continuous operation were as follows. Ozone removal rate = 85% Hydrogen sulfide deodorization rate = 14%

Comparative Example 2 In order to see the effect of peroxide, a tableting product (activated carbon content of about 20%) containing activated carbon commercially available as an ozone decomposer and Kanuma soil as main components was used as an ozone deodorizing catalyst. The same test as in Example 6 was carried out. The results after 24 hours of continuous operation were as follows. Ozone removal rate = 75% Hydrogen sulfide deodorization rate = 45%

Comparative Example 3 In order to see the effect of peroxide, in Example 5, 400 g of activated carbon, 400 g of synthetic zeolite and 100 g of sodium salt of carboxymethyl cellulose as a binder were used, and ozone was used without using 50% calcium peroxide. A deodorizing catalyst was produced and tested in the same manner as in Example 6.
The results after 24 hours of continuous operation were as follows. Ozone removal rate = 88% Hydrogen sulfide deodorization rate = 67%

[0031]

EFFECT OF THE INVENTION The ozone deodorizing catalyst of the present invention is excellent in deodorizing treatment ability against a malodor causing substance and also excellent in unreacted ozone treating ability, and the method of the present invention is effective for all malodors from household use to industrial use. Can be deodorized.

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location B01J 27/232 A 6750-4G

Claims (6)

[Claims] 1. A deodorizing method characterized by using a treating agent containing a peroxide when deodorizing a gas containing a malodorous component in the presence of ozone. 2. The deodorizing method according to claim 1, wherein the peroxide is at least one selected from barium peroxide, calcium peroxide, zinc peroxide, sodium percarbonate and sodium perborate. 3. The deodorizing method according to claim 1, wherein the treating agent contains activated carbon. 4. A treatment agent containing a peroxide for deodorizing a gas containing a malodorous component in the presence of ozone. 5. The treating agent according to claim 4, wherein the peroxide is at least one selected from barium peroxide, calcium peroxide, zinc peroxide, sodium percarbonate and sodium perborate. 6. The treating agent according to claim 4 or 5, which contains activated carbon.