KR20030023344A - Method for Removing Ozone Using Natural Manganese Ore as a Catalyst - Google Patents

Abstract

PURPOSE: A method for removing ozone using natural manganese ore catalyst having excellent catalytic activity under sever conditions is provided. CONSTITUTION: The method comprises the steps of (a) fabricating a catalyst made of natural manganese ore containing 60 to 95 wt.% of pyrolusite (β-MnO2) and 0.5 to 20 wt.% of iron oxide, wherein the catalyst contains 0.1 to 5.0 wt.% of transition metals such as Zn, Fe, Co, Ni, Cu, Au, Pt, Pd, and Rh and (b) treating air or gas containing ozone at a temperature in a range of room temperature to 200°C using the catalyst obtained in the step (a), wherein the natural manganese ore catalyst is fabricated by (a1) crushing the natural manganese ore into particles having a size of 0.1-50 micrometers, (a2) adding the transition metal to the particles, (a3) dispersing the natural manganese ore particles into water, thereby obtaining natural manganese ore slurry, and (a4) coating the natural manganese ore slurry on a structure such as pallet, saddle, cylinder and metal plate.

Description

Method for Removing Ozone Using Natural Manganese Ore as a Catalyst}

The present invention relates to a method for removing ozone. More specifically, the present invention relates to a method for removing ozone using a natural manganese ore containing pyrrolusite and iron (III) oxide as a main component as a catalyst.

In general, ozone (O ₃ ) has a very strong oxidation ability because of electrophilic and nucleophilic reactions have been used for sterilization, control of taste and smell, color removal. However, ozone is the main cause of photochemical smog when it remains unreacted in the air, and because of its strong oxidizing power, when exposed to the human body in the range of 0.1 to 1 ppm, Not only cause the respiratory diseases, etc., but also cause odor, causing discomfort. In particular, the need for regulation has been raised due to the continuous generation of various industrial processes, plasma processing processes, household appliances such as refrigerators, photocopiers, sterilizers, aircraft, etc., and emissions to the atmosphere. The government is tightening regulations related to this issue.

As a method for removing ozone, adsorption / decomposition by activated carbon, catalytic decomposition and the like are known.

Among the above methods, the adsorption method has a disadvantage in that it is economical, such as using an adsorbent made of a porous material such as activated carbon or zeolite, or because the performance of the adsorbent is deteriorated according to the adsorption, causing trouble to regenerate it. On the other hand, the catalytic decomposition method can overcome the disadvantages of the above-mentioned adsorption method, and the device is simple and easy to handle, and its utilization is expanding, and research on this has been actively conducted. In this regard, conventionally, ozone decomposition catalysts prepared by impregnating manganese dioxide (MnO ₂ ) in honeycomb are widely known, but have sufficient ozone decomposition activity in a severe environment in which a gas containing a high concentration of ozone has to be treated in a large amount. I couldn't expect it.

In order to overcome this problem, a method of supporting manganese dioxide on a support such as titania, a thin coating with manganese dioxide titania and then supporting various transition metals (Cu, Fe, etc.) and / or precious metals (Pd, Pt, Rh, etc.) Catalysts are used.

US Pat. No. 5,232,886 discloses clay or carbon; Manganese dioxide; Optionally titania; And / or a catalyst, an oxide of an alkali metal or an alkaline earth metal, consisting of an oxide of a metal selected from the group consisting of copper, cobalt, iron, nickel and silver; manganese dioxide; Optionally titania; And / or catalysts made of clay or carbon. The catalyst is prepared in the form of a slurry and used as a wash coating on a structure such as honeycomb, has been reported to have excellent ozone decomposing activity and durability in harsh environments.

U. S. Patent No. 5,187, 137 discloses an ozone reduction catalyst consisting of manganese dioxide and metal palladium and / or palladium oxide as essential components, which active ingredients are supported in a thin film form on cordierite, metal support.

Japanese Patent Laid-Open No. 8-10619 supports manganese dioxide and palladium oxide on a silica-boria-alumina support, and optionally silver (Ag), iridium (Ir), and lanthanum (La). The catalyst which further added metals, such as these, is disclosed. According to the present invention, the catalyst can be supported and used on a monolithic structure, and has been described as having an advantage of significantly preventing deactivation even when used for a long time at room temperature.

Recently, a catalyst has been developed in which an active metal component is introduced in the form of a multilayer coating on a support. PCT International Publication No. WO / 13772 discloses an active ingredient consisting of manganese dioxide or a palladium-containing material as a first coating on a refractory support such as alumina. And a catalyst composition provided with a second coating with an active ingredient selected from platinum and rhodium containing materials, silver oxides, and combinations thereof. According to the invention, it is described that the ozone removal characteristics are excellent even in a high humidity and low temperature environment of 50% or more.

Looking at the above-described conventional catalyst, the mainstream is a form in which manganese dioxide is used as a basic active ingredient and supported or separately supported or selectively with transition metals or precious metals. However, in order to prepare the catalyst, a number of processes for separately preparing and supporting each single material or precursor used as the support and the active ingredient are required, which is disadvantageous in terms of production cost of the catalyst. In particular, considering the fact that ozone generation sources are gradually diversified from huge industrial processes to general home appliances, a catalyst that can reduce costs significantly and has an ozone removal activity and sustainability equal to or higher than that of the prior art is required, and is easily manufactured. It's happening.

Accordingly, the present inventors have conducted research to overcome the problems of the prior art, and as a result, natural manganese ore containing pyrrolusite as β-MnO ₂ as a first main component and iron (III) oxide as a second main component When used as an ozone removal active ingredient, it was found that not only exhibits ozone decomposition performance equivalent to that of a conventionally known catalyst, but also can significantly reduce costs while maintaining long-term activity.

Accordingly, an object of the present invention is to provide a method for effectively removing ozone present in the atmosphere or gas using a catalyst composed of a natural manganese ore or a combination of natural manganese ores and various active metals.

Another object of the present invention is to provide an ozone removal method having excellent efficiency even in harsh environments and long time use.

In order to achieve the above and other purposes, the ozone removal method of the present invention is to treat the atmosphere or gas containing ozone in the atmosphere or gas by treating in the presence of a catalyst consisting of natural manganese ore and temperature conditions of 200 ℃ at room temperature The ozone is removed, and the natural manganese ore contains 60 to 95% by weight of pyrrolusite as β-MnO ₂ as the first main component and 0.5 to 20% by weight of iron (III) oxide as the second main component. do.

The present invention can all be achieved by the following description.

Usually, natural manganese ores differ in their properties depending on the crystal structure of MnO ₂ contained as a main component in the ore. More specifically, such MnO ₂ is generally divided into α-MnO ₂ (Psilomelane group), β-MnO ₂ (Pyrolusite), Ramsdellite, Manganite, Rhodochrosite, Braunite, Hansmanmite, Bixbyite, Jacobsite, Bementite, etc., and α-MnO ₂ is further subdivided into Cryptomelane, Hollandite, Coronadite, Psilomalane, etc., but Psilomelane, α-MnO ₂ , and Pyrolusite, β-MnO ₂ , account for the majority.

The molecular formula, crystal structure, and hardness according to the type of MnO ₂ contained as a main component in natural manganese ore are shown in Table 1 below.

ore Molecular formula Crystal structure Hardness α-MnO ₂ (Psilomelane Group) CryptomelaneHollanditePsilomelaneCoronadite KMn ₈ O ₁₆ BaMn ₈ O ₁₆ BaMn ₈ O ₁₆ PbMn ₈ O ₁₆ Tetragonal 5 to 6 Pyrolusite β-MnO ₂ Octahedral 6 to 7 Ramsdellite γ-MnO ₂ 3 Manganite γ-MnOOH 4 Rhodochrosite MnCO ₃ 3.5 to 4.5 Braunite Mn ₆ SiO ₁₂ 6.0 to 6.5 Hausmannite Mn ₃ O ₄ 4.8 Bixbyite Mn ₂ Fe ₂ O ₃ 6.0 Jacobsite MnFe ₂ O ₄ 6.0

Natural manganese ores used as catalyst components in the present invention are mostly found in the surface deposits and have a complex oxide form consisting of oxides such as Mn, Fe, Ca, Mg, Al, and Si. Since such natural manganese ore itself serves as both the active ingredient and the support at the same time, it can be used only by a simple mechanical operation without going through a separate process. In particular, the natural manganese ore used in the present invention contains 60 to 95% by weight of pyrrolusite as β-MnO ₂ as the first main component, and 0.5 to 20% by weight of iron (III) oxide as the second main component. Average chemical composition and physical properties of one embodiment of the natural manganese ore usable in the present invention are shown in Tables 2 to 4.

Composition of Manganese Ore Item Mn SiO ₂ Al ₂ O ₃ Fe CaO MgO ¹⁾ O ₂ balance of Mn and Fe weight% 51.85 3.13 2.51 3.86 0.11 0.25 38.33

^{1) In} the case of Mn and Fe, MnO ₂ , Mn ₂ O ₃ , Mn ₃ O ₄ , FeO, Fe ₂ O ₃ , Fe ₃ O ₄ exist, but MnO ₂ and Fe ₂ are most present in nature Assuming O ₃ , the amount of MnO ₂ represents about 84% by weight.

Natural Manganese Ore Diffraction plane spacing 3.11 2.39 2.15 1.62 Strength ratio 1.0 0.5 0.2 0.4

As can be seen from the table, the peak of the natural manganese ore shows a measured value similar to pyrrolusite which is β-MnO ₂ , such as having a maximum intensity at 3.11 Hz.

Average molecular size (mm) 0.359, 0.715 Specific gravity (㎏ / g) 3980 Specific volume of voids (cm 3 / g) 0.0392 (5-3,000 kPa) Specific surface area (㎡ / g) 11.0

As can be seen from the chemical composition shown in Table 2, since the natural manganese ore contains various metal oxides as other components in addition to pyrrolusite and iron oxide, synergistic effects are caused between components, and thus denitrification compared to catalysts of individual components only. Performance can be improved.

The catalyst using the natural manganese ore of the present invention may be prepared in the form of a catalyst body coated on a catalyst body or an extruded catalyst body by grinding in powder form. The basic principle of the production method of such a catalyst body is already well known in the art.

An example of a method of extruding the natural manganese ore in the form of a catalyst may be described as follows.

First, 80 to 95% by weight of natural manganese ore, 3 to 30% by weight of water, and 1 to 10% by weight of a binder for maintaining mechanical strength are kneaded, and then kneader is kneaded. Knead evenly using. Such binder components include inorganic binders such as silica sol, alumina sol, tartan sol, kaolin, bentonite, montmorilite, and clays free of alkali metals, and polyvinyl alcohol, glycerin, methyl cellulose, hydroxy methyl cellulose and hydroxy. Organic binders such as propyl methyl cellulose can be used. Then, it is molded into a catalyst body such as honeycomb and saddle through an extruder (for example, an orga-screw type extruder), and may be manufactured by drying and firing.

On the other hand, an example of a method of coating the natural manganese ore on the structure is as follows. Such a structure is not limited to honeycomb, and various types of structures such as pellets, saddles, cylinders, and metal plates may be used. First, a natural manganese ore is pulverized (preferably about 0.1 to 50 μm) and added to and dispersed in water to prepare a slurry having a natural manganese ore content of about 20 to 60 wt%, preferably 20 to 40 wt%. . In addition, additives such as a binder for firmly fixing the natural manganese ore on the structure to maintain mechanical strength and a dispersant for uniformly dispersing the natural manganese ore powder in water as a medium may be added. Such binder components include the aforementioned organic or inorganic binders, and are preferably used to have a content of 2 to 30% by weight in the slurry. In addition, as a dispersing agent, ammonium, amine, carboxyl-type polyelectrolyte, etc. can be used, Preferably it is used at 0.1-2 weight%. The slurry prepared as described above is applied to the structure by various methods such as dip, spray, roll coating, and the like, and then dried under firing in an air atmosphere. At this time, the amount of the catalyst component fixed on the structure preferably has a range of about 50 ~ 330g / L.

Meanwhile, in the present invention, a catalyst having a form in which precious metals such as platinum, palladium, and rhodium and transition metals such as zinc, iron, cobalt, nickel, and copper are additionally introduced into the natural manganese ore in order to improve catalyst performance. The transition metal precursors available at this time include zinc nitrate hydrate, zinc acetate dihydrate, iron acetate, iron nitrate dihydrate, and iron oxalate hydrate. oxalate dihydrate, cobalt nitrate hexahydrate, cobalt acetate, etc. Precious metal precursors include palladium chloride, palladium nitrate, and platinum nitrate chloride. , Silver nitrate (Silver nitrate) and the like, but is not necessarily limited thereto.

The additional metal component may be introduced as a single component or a mixed component, and preferably has an amount of about 0.1 to 5 wt% based on the weight of the natural manganese ore.

For example, the catalyst body in the form of an extruded body is extruded after kneading and kneading by adding an appropriate amount of additives such as the above-described plasticizer and binder to the natural manganese ore powder after carrying out the additional metal component. Can be prepared via.

In addition, the coated catalyst body may also be prepared by various methods. As an example of such a method, the additional metal component is supported on a natural manganese ore powder, followed by drying and firing (preferably 400 to 450 ° C.), and then powdered to prepare a slurry by the above-described method. Apply. As another example, a slurry may be prepared by mixing an additional metal component with natural manganese ore powder and then coated on the structure, or as described above, the structure coated with the natural manganese ore is immersed in a solution in which the additional metal component is dissolved and dried. And it can be manufactured through a calcination process (preferably 400 ~ 450 ℃).

According to the invention. The catalyst prepared as described above may be used to remove ozone in a gas containing ozone. At this time, the treatment temperature of the ozone-containing gas is about 200 ° C or lower, and preferably in the range from room temperature to 200 ° C. In addition, the amount of gas that can be treated and the ozone concentration in the gas vary depending on the characteristics of the catalyst. For example, a catalyst prepared using only natural manganese ore is 95% by treating a gas supplied at an ozone concentration of 1 to 10 ppm at room temperature and a gaseous hourly space velocity (GHSV) of 10,000 to 50,000 hr ^-1 . The above ozone removal efficiency can be achieved. In addition, catalysts made of natural manganese ore and additional metal components can achieve ozone removal efficiency of more than 90% by treating gas supplied at ozone concentration of 1 to 25 ppm and space velocity of 10,000 to 100,000 hr ^-1 at room temperature. have.

As described above, the catalyst of the present invention, unlike conventionally known catalysts, can use natural manganese ore itself and thus can be manufactured more simply and at low cost, and has an ozone removal efficiency equal to or higher than that of a conventional catalyst. In addition, the natural manganese ore used in the catalyst has the advantage of being able to prevent the degradation of the catalyst activity due to long time use.

The present invention can be more clearly understood by the following examples, which are only intended to illustrate the present invention and are not intended to limit the scope of the invention.

Example 1

250 g of natural manganese ore containing 84% by weight of pyrrolusite and 4% by weight of iron (III) were ground to a particle size of 0.1 to 50 µm and poured into 500 g of water to obtain a concentration of about 33% by weight of natural manganese ore. Was made. At this time, 0.5ml (about 1g) of 5468CF (NOP Co.) was added as a dispersant so that the particles of the natural manganese ore powder were evenly dispersed in water as a medium, and 16g of alumina sol was added as a binder. Then, a slurry was prepared by mixing and grinding at 600 rpm for 15 minutes using a high speed mill (trade name: Attrition Mill).

On the other hand, the honeycomb made of cordierite having a length of 150 mm (length) x 150 mm (width) x 50 mm (length) was wash-coated to be about 100 g / L by dipping in the slurry. Then, the mixture was dried at 105 ° C. for 12 hours and then calcined at 400 ° C. for 4 hours in an air atmosphere to prepare a catalyst body.

Ozone removal performance of the catalyst prepared as described above was measured as follows.

The test was performed under a space velocity of 30,000 hr ⁻¹ ozone containing gas, an ozone concentration of 1 ppm and room temperature conditions.

At this time, the ozone removal rate is determined by the following Equation 1, the results are shown in Table 5 below.

Comparative Example 1

Impregnated onto Aldrich's alumina (100 mesh) support using manganese nitrate as a precursor of manganese dioxide (MnO ₂ ), and then calcined under an air atmosphere at 400 ° C. for 4 hours to provide MnO ₂ [5] / Al ₂ O ₃ Was prepared. Then, after the slurry was prepared in the same manner as in Example 1 using the catalyst prepared as described above was washed with a honeycomb. Thereafter, the mixture was dried at 105 ° C. for 12 hours and then calcined at 400 ° C. for 4 hours in an air atmosphere to prepare a catalyst body. Separately, a manganese dioxide slurry was prepared and was washed with a honeycomb in the same manner as in Example 1 to prepare a catalyst body.

The ozone removal performance of the catalyst prepared as described above was measured under the same conditions as in Example 1, and the results are shown in Table 5 below.

Example 2

Using the catalyst prepared as in Example 1, by changing the space velocity and ozone concentration of the ozone-containing gas, the ozone removal performance was measured accordingly. At this time, the space velocity was changed in the range of 15,000 to 30,000 hr ⁻¹ , and the ozone concentration was in the range of 1 to 5 ppm. The results are shown in Table 5 below.

Comparative Example 2

Using the catalyst prepared as in Comparative Example 1, the performance of the catalyst was tested by changing the space velocity and ozone concentration of the ozone-containing gas under the same reaction conditions as in Example 2. The results are shown in Table 5 below.

Space velocity (GHSV) (hr ^-1 ) NMO MnO ₂ / Al ₂ O ₃ MnO ₂ Ozone removal rate (%) Ozone removal rate (%) Ozone removal rate (%) 1 ppm 4.5 ppm 1 ppm 4.5 ppm 1 ppm 4.5 ppm 15,000 99.8 99.6 68.5 44.6 99.3 99.2 20,000 99.6 99.3 63.0 33.0 99.3 99.0 25,000 99.3 99.2 58.2 25.7 99.2 98.2 30,000 99.0 99.1 55.7 23.7 99.0 98.1

According to the table, in the case of the catalyst body having a form in which manganese dioxide was supported on alumina, the ozone removal rate was about 25 to 45% compared with the result obtained in Example 1. In addition, when pure MnO ₂ was used, the absolute amount of manganese oxide was much higher than that of the alumina catalyst supporting manganese dioxide, and thus the ozone removal rate was almost comparable to that of the catalyst of Example 1, but a large amount of manganese dioxide was used. It was economically disadvantageous.

Example 3

The catalyst prepared as in Example 1 was used to test the ozone removal performance over the reaction time. The reaction conditions were 5 ppm ozone concentration, room temperature, and a space velocity of 8,000 hr ⁻¹ , and the test results are shown in Table 6 below. At this time, ozone was supplied using an ozone lamp.

time One 3 5 7 10 15 20 26 39 44 63 % Conversion 99.8 100.0 100.0 100.0 100.0 99.9 99.8 99.6 99.7 99.9 99.8

time 92 98 105 114 123 140 161 170 186 % Conversion 99.8 100.0 99.8 99.9 99.9 99.9 99.9 99.9 99.9

Example 4

Fe (NO ₃ ) ₃ .9H ₂ O (Aldrich) was impregnated into the natural manganese ore (NMO) powder used in Example 1, dried at 110 ° C. for 12 hours, and calcined at 400 ° C. for 4 hours in an air atmosphere. A Fe ₂ O ₃ [5] / NMO catalyst was prepared. The catalyst was prepared as a slurry as in Example 1 and coated on a honeycomb to prepare a catalyst body, and ozone removal performance was measured under a space velocity of 30,000 hr ⁻¹ , an ozone concentration of 1 ppm, and room temperature. The results are shown in Table 7 below.

Comparative Example 3

After impregnating onto Aldrich's alumina (100 mesh) support, it was dried at 110 ° C. for 12 hours and calcined at 400 ° C. for 4 hours in an air atmosphere to produce Fe ₂ O ₃ [5] / Al ₂ O _3. Catalyst was prepared. The catalyst was prepared as a slurry as in Example 1, coated on a honeycomb to prepare a catalyst, and ozone removal performance was measured under the same conditions as in Example 4. The results are shown in Table 7 below.

Example 5

Using the catalyst prepared as in Example 4, by varying the space velocity and ozone concentration of the ozone-containing gas, the ozone removal performance was measured at room temperature. At this time, the space velocity was in the range of 15,000 to 50,000 hr ⁻¹ , and the ozone concentration was changed in the range of 1 to 5 ppm. The results are shown in Table 7 below.

Comparative Example 4

Using the catalyst prepared as in Comparative Example 3, the performance of the catalyst was tested by changing the space velocity and ozone concentration of the ozone-containing gas under the same reaction conditions as in Example 5. The results are shown in Table 7 below.

Space velocity (GHSV) (hr ^-1 ) Fe ₂ O ₃ [5] / NMO Fe ₂ O ₃ [5] / Al ₂ O ₃ Ozone removal rate (%) Ozone removal rate (%) 1 ppm 4.5 ppm 1 ppm 4.5 ppm 15,000 99.9 99.9 3.1 3.1 20,000 99.9 99.8 2.8 2.7 25,000 99.7 99.7 2.2 2.0 30,000 99.6 99.5 2.0 1.4 40,000 99.3 99.2 0.8 0.3 50,000 99.1 99.0 0.7 0.1

Example 6

The natural manganese ore (NMO) powder used in Example 1 was impregnated with different amounts of Zn (NO ₃ ) ₂ .6H ₂ O (Aldrich), and then dried at 110 ° C. for 12 hours and at 400 ° C. for 4 hours. Firing in an air atmosphere produced ZnO [0.1] / NMO catalyst and ZnO [0.5] / NMO catalyst. The catalyst was prepared as a slurry as in Example 1 and coated on a honeycomb to prepare a catalyst body. The ozone removal performance was measured at room temperature by varying the space velocity and ozone concentration of the ozone-containing gas. At this time, the space velocity was in the range of 15,000 to 50,000 hr ⁻¹ , and the ozone concentration was changed in the range of 1 to 5 ppm. The results are shown in Table 8 below.

Space velocity (GHSV) (hr ^-1 ) ZnO [0.1] / NMO ZnO [0.5] / NMO Ozone removal rate (%) Ozone removal rate (%) 1 ppm 4.5 ppm 1 ppm 4.5 ppm 15,000 99.9 99.9 99.9 99.9 20,000 99.9 99.9 99.9 99.9 25,000 99.9 99.8 99.9 99.8 30,000 99.8 99.6 99.8 99.6 40,000 99.6 99.4 99.7 99.5 50,000 99.4 99.2 99.5 99.3

Example 7

Except for the fact that the content of ZnO impregnated in natural manganese ore (NMO) is 2% by weight, the catalyst body prepared according to the same method as in Example 6 was used at high ozone concentration (15 ppm) according to the space velocity. Ozone removal performance was measured. The results are shown in Table 9 below.

Space velocity (GHSV) (hr ^-1 ) Ozone removal rate (%) 13,073 99.9 26,147 99.9 52,294 99.4 78,441 96.6 104,588 89.8 130,736 85.4 169,956 81.7

Relative humidity 55.8% RH (using ozone lamp)

Example 8

The natural manganese ore (NMO) powder used in Example 1 was impregnated with varying content of AgNO ₃ (Aldrich), and then dried at 110 ° C. for 12 hours and calcined at 400 ° C. for 4 hours in an air atmosphere to give Ag [0.1 ] / NMO catalyst and Ag [0.5] / NMO catalyst were prepared. The catalyst was prepared as a slurry as in Example 1, coated on a honeycomb to prepare a catalyst body, and the ozone removal performance was measured at room temperature. At this time, the space velocity was in the range of 15,000 to 50,000 hr ⁻¹ , and the ozone concentration was changed in the range of 1 to 5 ppm. At this time, ozone was generated from the ozone generator and used. The results are shown in Table 10 below.

Example 9

The natural manganese ore (NMO) powder used in Example 1 was impregnated with Pt (NO ₃ ) (Merk) and Pd (NO ₃ ) ₂ (Aldrich), respectively, and dried at 110 ° C. for 12 hours and at 400 ° C. for 4 hours. It was calcined under an air atmosphere to prepare Pt [0.5] / NMO catalyst and Pd [0.5] / NMO catalyst. The catalyst was prepared as a slurry as in Example 1, coated on a honeycomb to prepare a catalyst, and the ozone removal performance was measured at room temperature. At this time, the reaction conditions were the same as in Example 8, the results are shown in Table 10 below.

Space velocity (hr ^-1 ) Ag [0.1] / NMO Ag [0.5] / NMO Pt [0.5] / NMO Pd [0.5] / NMO Ozone removal rate (%) Ozone removal rate (%) Ozone removal rate (%) Ozone removal rate (%) 1 ppm 4.5 ppm 1 ppm 4.5 ppm 1 ppm 4.5 ppm 1 ppm 4.5 ppm 15,000 99.9 99.9 99.9 99.9 99.9 99.9 99.9 99.9 20,000 99.9 99.9 99.9 99.9 99.9 99.9 99.9 99.9 25,000 99.9 99.8 99.9 99.8 99.9 99.7 99.9 99.9 30,000 99.6 99.5 99.7 99.6 99.7 99.3 99.9 99.8 40,000 99.5 99.4 97.5 99.3 99.3 99.1 99.7 98.6 50,000 99.4 99.3 95.4 99.2 99.1 99.0 99.5 96.4

Example 10

The catalyst body was prepared in the same manner as in Example 9 except that the sintering temperature was changed to 500 ° C. after Pd (NO ₃ ) ₂ (Aldrich) was impregnated with natural manganese ores in the preparation of the Pd [0.5] / NMO catalyst. To prepare the ozone removal performance was measured. The results are shown in Table 11 below in comparison with Example 9.

Space velocity (GHSV) (hr ^-1 ) Ozone removal rate (%) 400 ℃ 500 ℃ 15,000 99.9 99.7 99.9 99.7 20,000 99.9 99.4 99.9 99.6 30,000 99.9 99.2 99.8 99.3 40,000 98.7 98.2 99.6 96.1 50,000 97.5 96.7 99.4 94.2

Example 11

For the catalyst body prepared in Example 1, ozone removal performance was tested while changing the concentration of ozone in the range of about 1 to 25 ppm. Ozone was supplied using an ozone lamp, the results are shown in Table 12 below.

Space velocity (hr ^-1 ) Inlet ozone concentration (ppm) Ozone removal rate (%) 6536 25.2 99.96 13073 13.36 99.42 26147 7.62 99.01 39220 4.03 89.57 52294 3.65 87.78 65368 2.92 86.39 78441 2.65 85.32

Example 12

In the catalyst body prepared as in Example 1, the content of natural manganese ore (NMO) fixed to the honeycomb was changed to 50 g / l, 100 g / l, 200 g / l and 330 g / l, respectively, and 0.3 wt% of Pd. It was supported. The ozone removal performance was measured according to the space velocity change of the catalyst body, and the results are shown in Table 13 below.

Space velocity (hr ^-1 ) 50g / ℓ 100 g / ℓ 200 g / ℓ 330 g / ℓ 24794 99.99 99.99 99.99 99.99 37261 99.75 99.81 99.81 99.80 49777 99.52 99.54 99.53 99.53 62293 99.48 99.50 99.51 99.50 74828 99.12 99.21 99.20 99.18

As described above, when the ozone removal catalyst using the natural manganese ore of the present invention is used, the ozone removal performance of the manganese dioxide, which is known to have ozone removal performance in the past, or a catalyst carrying a transition metal or a noble metal, can exhibit more than equivalent ozone removal performance. It was confirmed that there is. In addition, as can be seen in Example 3, it was confirmed that there is almost no change in catalytic activity according to long-term use.

Since the catalyst prepared using the natural manganese ore of the present invention has a complex oxide form containing pyrrolusite and iron (III) oxide as its main components and various oxides, a synergistic effect is induced to effectively remove ozone present in the atmosphere or gas. It can remove, and has the advantage of excellent ozone removal performance even in harsh environment and long time use.

All simple modifications and variations of the present invention fall within the scope of the present invention, and the specific scope of the present invention will be apparent from the appended claims.

Claims (11)

Atmospheric or gas containing ozone is treated at a temperature of 200 ° C. at room temperature and in the presence of a catalyst composed of natural manganese ore to remove ozone contained in the atmosphere or gas, and the natural manganese ore is 60 to 1 as the main component. 95% by weight of β-MnO ₂ pyrrolusite and 0.5 to 20% by weight of iron (III) oxide as the second main component. The method of claim 1, wherein the catalyst further comprises 0.1 to 5.0% by weight of an additional metal component selected from one or two or more selected from the group consisting of Zn, Fe, Co, Ni, Cu, Au, Pt, Pd and Rh. Ozone removal method characterized by the above-mentioned. The ozone removal method according to claim 1, wherein the catalyst has a form of a catalyst body obtained by extruding a powder obtained by grinding the natural manganese ore into a size of 0.1 to 50 µm. The slurry of claim 1, wherein the catalyst grinds the natural manganese ore to a size of 0.1 to 50 μm and disperses it in water to produce a slurry having a content of 20 to 60 wt% of the natural manganese ore. Ozone removal method characterized in that it has the form of a catalyst body coated on. 5. The method of claim 4, wherein said structure is selected from the group consisting of honeycomb, pellets, saddles, cylinders and metal plates. The ozone removal method according to claim 2, wherein the catalyst has a form of a catalyst body extruded after the additional metal component is supported on the natural manganese ore powder crushed to a size of 0.1 to 50 µm. [Claim 3] The content of the natural manganese ore according to claim 2, wherein the catalyst is dispersed in water after supporting the additional metal component in the powder of the natural manganese ore ground to a size of 0.1 to 50 µm. Ozone removal method characterized in that it has the form of a catalyst body coated on the structure after the slurry is prepared. The method of claim 2, wherein the catalyst is pulverized the natural manganese ore to the size of 0.1 to 50㎛ and dispersed in water to prepare a slurry having a content of 20 to 60% by weight of the natural manganese ore after the slurry on the structure Coating on; And a catalyst body produced by the method comprising the step of supporting the additional metal component on the coated structure. The ozone removal rate of the catalyst according to claim 1, wherein when the ozone-containing atmosphere or gas is treated at a space velocity of 10,000 to 50,000 hr ⁻¹ , an ozone concentration of ¹ to 10 ppm, and room temperature, the ozone removal rate of the catalyst is 95% or more. How to remove ozone. The ozone removal rate of the catalyst according to claim 2, wherein when the ozone-containing atmosphere or gas is treated at a space velocity of 10,000 to 100,000 hr ⁻¹ , an ozone concentration of ¹ to 25 ppm, and room temperature, the ozone removal rate of the catalyst is 90% or more. How to remove ozone. 9. The ozone removal method according to any one of claims 4, 7, and 8, wherein the amount of the catalyst component fixed on the structure is 50 to 330 g / l.