KR102643454B1 - Adsorbent for removal of hazardous gas and methode of manufacturing the same - Google Patents

Abstract

The adsorbent for removing harmful gases according to embodiments of the present invention includes activated carbon and copper oxide supported on the activated carbon. The adsorbent for removing harmful gases contains 2 to 6 parts by weight of copper oxide based on 100 parts by weight of activated carbon. Accordingly, the adsorption capacity and adsorption efficiency for harmful gases can be increased.

Description

Adsorbent for removing hazardous gases and method for manufacturing the same {ADSORBENT FOR REMOVAL OF HAZARDOUS GAS AND METHODE OF MANUFACTURING THE SAME}

The present invention relates to an adsorbent for removing harmful gases and a method for producing the same. More specifically, it relates to an adsorbent for removing harmful gases containing activated carbon and a method for producing the same.

Organic and inorganic harmful gases such as sulfur compounds and aldehydes can cause environmental pollution and have adverse effects on the human body's respiratory system, nervous system, and eyes.

Volatile organic compounds (VOCs) removal facilities are installed and operated to remove harmful gases, but it is impossible to remove all organic and inorganic harmful gases through this.

In particular, sulfur compounds that cause bad odors, such as methyl mercaptan, hydrogen sulfide, dimethyl sulfide, and dimethyl disulfide, have very small molecular sizes, so physical removal is limited.

Various methods have been proposed to remove bad odors. Generally, removal methods using high-temperature heat energy, decomposition using plasma, and dust collection methods using electricity are known.

The method of using thermal energy removes pollutants by burning gas with a high-temperature heat source. To remove contaminants, a temperature higher than the decomposition temperature of the target gas is required, so the heating process cost is high. To compensate for this, a catalyst is applied, which can lower the process temperature and selectively remove gas. For high process efficiency, catalyst performance and lifespan are very important. However, catalysts are vulnerable to poisoning, and damage can increase the differential pressure within the process. In addition, it is suitable for removing gases at high concentrations, but it is difficult to achieve high efficiency at low concentrations. To remove contaminants at room temperature, a large amount of catalyst is required, and the size of the process needs to increase accordingly. After the reaction, by-products may also exist, and additional equipment is needed to remove them, making the equipment larger.

The plasma method decomposes harmful gases down to the atomic level through plasma. However, the conditions for generating and maintaining plasma are difficult, which increases operating costs. In addition, after being decomposed down to the atomic level, contaminants can recombine to create third contaminants, and ozone is generated after the reaction, requiring additional removal equipment.

Because the electrostatic precipitating method uses electricity, the cost of maintaining the process is high. When organic matter or dust is collected, there is a risk of explosion due to static electricity or sparks.

For example, Republic of Korea Patent Publication No. 10-2068184 discloses an adsorbent containing a carbon-based core and an adsorbent shell, but research and development on methods to increase harmful gas removal efficiency and reduce operating costs is necessary. am.

Republic of Korea Patent Publication No. 10-2068184

One object of the present invention is to provide an adsorbent for removing harmful gases with excellent removal performance.

One object of the present invention is to provide a method for producing an adsorbent for removing harmful gases with excellent removal performance.

1. Activated carbon; and copper oxide supported on the activated carbon, wherein the copper oxide is contained in an amount of 2 to 6 parts by weight based on 100 parts by weight of the activated carbon.

2. The adsorbent for removing harmful gases according to 1 above, further comprising 0.1 to 1 part by weight of silver oxide based on 100 parts by weight of the activated carbon.

3. The adsorbent for removing harmful gases according to 1 above, further comprising 3 to 9 parts by weight of an organic acid per 100 parts by weight of the activated carbon.

4. In 1 above, the harmful gas is methyl mercaptan, hydrogen sulfide, dimethyl sulfide, and dimethyl disulfide. An adsorbent for removing harmful gases.

5. Preparing an impregnating composition containing copper oxide; And a method for producing an adsorbent for removing harmful gases, comprising the step of impregnating 2 to 6 parts by weight of copper oxide with the adhesion composition based on 100 parts by weight of activated carbon.

6. The method of producing an adsorbent for removing harmful gases according to item 5 above, wherein the activated carbon is impregnated with 0.1 to 1 part by weight of silver oxide based on 100 parts by weight.

7. The method of 5 above, wherein the impregnating composition further includes an organic acid, and the impregnating step further includes acid treating the activated carbon with the organic acid.

According to exemplary embodiments, the adsorbent includes activated carbon loaded with a predetermined amount of copper oxide. Harmful gases (e.g., methyl mercaptan, hydrogen sulfide, dimethyl sulfide, dimethyl disulfide) can be removed with high efficiency.

The adsorbent can more effectively remove harmful gases, including silver oxide.

Acid-treated adsorbents can have further improved harmful gas removal efficiency.

1 and 2 are schematic flowcharts showing a method of manufacturing an adsorbent for removing harmful gases according to example embodiments.

Embodiments of the present invention provide an adsorbent for removing harmful gases containing activated carbon carrying copper oxide. The adsorbent for removing harmful gases has excellent removal efficiency for harmful gases.

The adsorbent for removing harmful gases (hereinafter abbreviated as 'adsorbent') can remove harmful gases physically and chemically. The chemical removal may include chemical adsorption of harmful components of the harmful gas. The chemical removal may be performed by an oxidation reaction for the harmful gas.

For example, the harmful gas may include inorganic harmful gas and organic harmful gas. The harmful gas may include odor-causing gas and toxic gas.

In exemplary embodiments, the inorganic harmful gas may include methyl mercaptan, hydrogen sulfide, dimethyl sulfide, and dimethyl disulfide. The harmful gas can be oxidized into water (H ₂ O). For example, the adsorbent for removing harmful gases can chemically adsorb (remove) the hydrogen sulfide and the sulfur contained therein through an oxidation reaction. For example, chemical adsorption can form covalent bonds and have superior fixing power compared to physical adsorption.

Activated carbon contains pores inside the particles and can have a large surface area. The activated carbon can physically adsorb the harmful gas. For example, the activated carbon can adsorb the harmful gas through van der Waals bond.

In some embodiments, the particle size of the activated carbon may be about 0.3 to 4.75 mm. In the above particle size range, removal efficiency for harmful gases can be improved. Preferably, the particle size of the activated carbon may be about 1.7 to 2.36 mm.

For example, the activated carbon may include palm-based activated carbon, coal-based activated carbon, etc. The activated carbon may be granular, spherical, or pellet-shaped. Preferably, the activated carbon may be palm-based.

The activated carbon may be provided as impregnated activated carbon by supporting copper (Cu) oxide and/or silver (Ag) oxide, which will be described later. The copper oxide may have superior adsorption capacity compared to oxides of other metals.

In exemplary embodiments, the activated carbon may be acid treated. In this case, the specific surface area and active sites of the activated carbon may increase. Therefore, the carrying capacity for copper (Cu) oxide and/or silver (Ag) oxide can be increased, and the harmful gas adsorption capacity and selectivity can be improved.

In some embodiments, the acid treatment may promote a harmful gas reduction reaction of the copper (Cu) oxide and the silver (Ag) oxide. For example, the acid treatment helps maintain the oxide state of the copper (Cu) oxide and the silver (Ag) oxide. Accordingly, the reduction capacity for the harmful gas can be improved.

The adsorbent may include copper (Cu) oxide supported on the activated carbon.

The adsorbent may include about 2 to 6 parts by weight of the copper (Cu) oxide based on 100 parts by weight of the activated carbon.

If the copper (Cu) oxide is supported in less than about 2 parts by weight, the removal efficiency for harmful gases may be reduced. If the copper (Cu) oxide is supported in an amount exceeding about 6 parts by weight, it may not be sufficiently dissolved in the solvent, resulting in non-uniform adhesion and making mass production difficult. Accordingly, costs may increase even though the harmful gas removal efficiency is substantially saturated.

Preferably, the copper (Cu) oxide may be included in an amount of about 3 to 5 parts by weight based on 100 parts by weight of the activated carbon.

For example, the copper (Cu) oxide may include copper oxide (I; Cu ₂ O) or copper oxide (II; CuO). Preferably, copper(II) oxide, which has excellent reducing properties, can be used.

For example, copper(II) oxide can remove hydrogen sulfide by adsorbing the sulfur component of hydrogen sulfide through the reaction shown in Scheme 1 below.

[Scheme 1]

H ₂ S + CuO -> H ₂ O + CuS

In exemplary embodiments, silver (Ag) oxide may be supported on the activated carbon. The silver (Ag) oxide can chemically adsorb the harmful gas.

Additionally, the silver (Ag) oxide can promote the chemical adsorption reaction of the copper (Cu) oxide. For example, the silver (Ag) oxide can promote the oxidation of the harmful gas by promoting the reduction reaction of the (Cu) copper oxide.

In exemplary embodiments, the silver (Ag) oxide may include silver oxide (I; Ag ₂ O) or silver oxide (II; AgO). When silver(II) oxide is used, the oxidation reaction of the harmful gas may be promoted.

For example, silver(II) oxide can remove hydrogen sulfide through the reaction of Scheme 2 below.

[Scheme 1]

H ₂ S + AgO -> H ₂ O + AgS

In exemplary embodiments, the silver (Ag) oxide may be included in an amount of about 0.1 to 1 part by weight based on 100 parts by weight of the activated carbon. For example, if the silver (Ag) oxide is included in less than about 0.1 parts by weight, the harmful gas removal efficiency of the adsorbent may be reduced. If the silver (Ag) oxide is included in an amount exceeding about 1 part by weight, agglomeration or poisoning of the silver oxide particles may occur.

Preferably, the silver oxide may be included in an amount of about 0.2 to 0.5 parts by weight based on the activated carbon.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, this is only illustrative and the present invention is not limited to the specific embodiments described as examples.

1 is a schematic flowchart showing a method of manufacturing an adsorbent for removing harmful gases according to example embodiments. Hereinafter, a method of manufacturing an adsorbent for removing harmful gases according to exemplary embodiments will be described with reference to FIG. 1.

Prepare an impregnating composition containing copper (Cu) oxide (eg, step S10). The adhesion composition can attach the copper oxide to the external surface and internal pore surface of activated carbon particles.

In some embodiments, the adhesion composition may include an aqueous solution in which the copper (Cu) oxide is dispersed and/or dissolved. In some embodiments, the adhesion composition may include an organic solvent.

In exemplary embodiments, the adhesion composition may include about 2 to 6 parts by weight of copper (Cu) oxide based on 100 parts by weight of activated carbon to be impregnated. In this case, about 2 to 6 parts by weight of copper (Cu) oxide can be supported on the activated carbon through the adhesion composition, based on 100 parts by weight of the activated carbon.

In exemplary embodiments, the adhesion composition may include silver (Ag) oxide. For example, the adhesion composition includes both the copper (Cu) oxide and the silver (Ag) oxide, and deposits copper (Cu) oxide particles and silver (Ag) oxide particles on at least a portion of the inner and outer surfaces of the activated carbon particles. It can be adhered (coated).

In exemplary embodiments, about 0.1 to 1 part by weight of silver (Ag) oxide may be supported on the activated carbon through the adhesion composition, based on 100 parts by weight of the activated carbon.

In exemplary embodiments, activated carbon may be added to the impregnation composition, the impregnation composition may be stirred, and the solvent may be evaporated to support the copper (Cu) oxide and/or the silver v oxide on the activated carbon ( For example, step S20). Through this, an adsorbent for removing harmful gases can be manufactured. The solvent can be removed by heating or drying under reduced pressure.

Figure 2 is a schematic flowchart showing a method of manufacturing an adsorbent for removing harmful gases according to example embodiments. Descriptions of processes that are substantially the same as those described with reference to FIG. 1 may be omitted.

In exemplary embodiments, acid may be added to the adhesion composition (eg, step S30). For example, the activated carbon may be acid treated by acid added to the impregnating composition. For example, the acid treatment may be performed before depositing the copper (Cu) oxide.

The acid treatment may modify the properties of the outer surface and inner pore surface of the activated carbon. For example, the inner and outer surface areas of the activated carbon may increase, thereby increasing the hydrogen sulfide adsorption capacity of the copper (Cu) oxide and the silver (Ag) oxide.

In exemplary embodiments, the acid added to the adhesion composition may be an organic acid. For example, the organic acid may include a divalent organic acid having 2 to 6 carbon atoms.

For example, the divalent organic acid may include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, or derivatives thereof. Preferably, the divalent organic acid may include succinic acid or a derivative thereof.

In this case, the copper (Cu) oxide, silver (Ag) oxide, and organic acid can be more uniformly deposited on the activated carbon, and the manufacturing process can be simplified by unifying the impregnation and acid treatment processes.

In exemplary embodiments, the acid treatment may be performed with about 3 to 9 parts by weight of an organic acid based on 100 parts by weight of the activated carbon. Preferably, the organic acid may be used in an amount of about 5 to 7 parts by weight based on 100 parts by weight of the activated carbon.

For example, if the amount of the organic acid used is less than about 5 parts by weight based on 100 parts by weight of the activated carbon, the active site of the activated carbon may not substantially increase.

If the amount of the organic acid used exceeds about 7 parts by weight based on 100 parts by weight of the activated carbon, the activity of the activated carbon itself may be reduced due to closure of internal pores of the activated carbon or agglomeration phenomenon. In this case, the amount of harmful gas adsorption and removal may be reduced.

Adsorbents for removing harmful gases according to example embodiments may be applied to air purification filters. For example, an air purification filter can be manufactured by adsorbing and coating the adsorbent on a breathable material such as non-woven fabric. The adsorbent may be dispersed in a solvent and applied to the permeable material, and when the solvent is removed, the adsorbent may be adsorbed and coated on the permeable material.

The air purification filter can physically adsorb and remove harmful gases through the activated carbon, and chemically adsorb and remove harmful gases through the copper (Cu) oxide and silver (Ag) oxide.

Hereinafter, experimental examples including specific examples and comparative examples are presented to aid understanding of the present invention, but these are only illustrative of the present invention and do not limit the scope of the appended claims, and do not limit the scope and technical idea of the present invention. It is obvious to those skilled in the art that various changes and modifications to the embodiments are possible within the scope, and it is natural that such changes and modifications fall within the scope of the appended patent claims.

Example 1

Coconut-based activated carbon with an average particle diameter of 1.7-2.36 mm was prepared. An adhesion composition was prepared by dispersing 4 parts by weight of copper (II) oxide carbonate in deionized water per 100 parts by weight of activated carbon.

Activated carbon was vacuum stirred in a flask to remove impurities, and then the impurity composition was added. The adsorbent for removing harmful gases containing copper(II) oxide was prepared by drying the adhesion composition for 1 h at 100 ^o C and heat-treating it for 20 h at 170 ^o C in an oxygen atmosphere. The heat treatment temperature was set to the temperature at which copper(II) oxide carbonate decomposes. If the temperature is below the above temperature, it is difficult to form copper (Cu) oxide, and if the temperature is above the temperature, burning occurs.

Comparative Examples 1 to 5

Comparative Example 1 in the same manner as Example 1, except that nickel (II) oxide, manganese (IV) oxide, iron (III) oxide, zinc oxide, and magnesium oxide were added to activated carbon instead of copper (II) oxide. Adsorbents from 5 to 5 were prepared.

Experimental Example 1

After filling the reactor with the adsorbents of Example 1 and Comparative Examples 1 to 5, the time taken for the removal rate of H ₂ S to reach 94% by passing a gas containing 60 ppm of H ₂ S at 0.25 m/s (breakthrough time) ) was measured and shown in Table 1 below.

The removal rate was calculated based on the amount of hydrogen sulfide discharged from the rear end of the reactor compared to the front end of the reactor.

Supporting ingredient Content (parts by weight) 94% breakthrough time (minutes) Agglomeration? Example 1 CuO 4 840 X Comparative Example 1 NiO 4 0 X Comparative Example 2 MnO 4 93 X Comparative Example 3 FeO 4 0 X Comparative Example 4 ZnO 4 225 X Comparative Example 5 MgO 4 0 X

Referring to Table 1, it was confirmed that the hydrogen sulfide removal capacity and removal efficiency of the examples using copper oxide were significantly improved compared to the comparative examples using metal oxides.

Examples 2, 3 and Comparative Examples 6 to 8

In Example 1, an adsorbent was prepared by supporting copper (II) oxide in the amount shown in Table 2 below, based on 100 parts by weight of activated carbon.

The breakthrough time of the adsorbent was evaluated and is shown in Table 2 below.

Supporting ingredient Content (parts by weight) 94% breakthrough time (minutes) Aggregation or not Example 2 CuO 2 540 X Example 3 CuO 6 900 O Comparative Example 6 CuO One 150 X Comparative Example 7 CuO 8 795 O Comparative Example 8 CuO 10 780 O

Referring to Table 2, in the case of comparative examples in which the Cu content exceeded 6 parts by weight relative to 100 parts by weight of activated carbon, agglomeration of the adsorbent occurred. In addition, in the comparative example where the Cu content was less than 2 parts by weight compared to 100 parts by weight of activated carbon, the breakthrough time was reduced.

Examples 4 to 6

In Example 1, silver(II) oxide was added to the impregnation composition in the amount shown in Table 3 below based on the total weight of activated carbon, and through this, copper(II) oxide and silver(II) oxide were impregnated on the activated carbon to form an adsorbent. Ready.

Supporting ingredient Content (parts by weight) 94% breakthrough time (minutes) Agglomeration? Example 4 CuO/AgO 4 / 0.25 1390 X Example 5 CuO/AgO 4 / 0.5 1250 X Example 6 CuO/AgO 4 / 1 1103 X

Referring to Table 3, when Ag was added during the adhesion process of activated carbon, the highest breakthrough time was observed at 0.25%, and as the content increased, it actually decreased.

Examples 7 to 9

In Example 4, an adsorbent was prepared by adding succinic acid in the amount shown in Table 4 below based on 100 parts by weight of activated carbon to the impregnation composition, and then adsorbing the activated carbon.

The breakthrough time of the prepared adsorbent was evaluated and is shown in Table 4 below.

acid composition Content (parts by weight) 94% breakthrough time (minutes) Agglomeration? Example 7 CuO/AgO/succinic acid 4 / 0.25 / 3 1050 X Example 8 CuO/AgO/succinic acid 4 / 0.25 / 6 1800 X Example 9 CuO/AgO/succinic acid 4 / 0.25 / 9 950 O

Referring to Table 4, it was confirmed that the harmful gas removal capacity and efficiency of the adsorbent increased when 6% succinic acid was used in the adhesion process of activated carbon. However, when 9% succinic acid was used as in Example 9, the performance decreased due to agglomeration.

Claims (7)

activated carbon; and
It includes copper oxide and silver oxide containing AgO supported together on the activated carbon,
An adsorbent for removing harmful gases, wherein the copper oxide is contained in an amount of 2 to 6 parts by weight based on 100 parts by weight of the activated carbon, and the silver oxide is contained in an amount of 0.1 to 1 part by weight based on 100 parts by weight of the activated carbon.
delete The adsorbent for removing harmful gases according to claim 1, further comprising 3 to 9 parts by weight of an organic acid per 100 parts by weight of the activated carbon.
The method of claim 1, wherein the harmful gas is methyl mercaptan, hydrogen sulfide, dimethyl sulfide, and dimethyl disulfide. The adsorbent for removing harmful gases.
Preparing an impregnating composition containing copper oxide and silver oxide containing AgO; and
A method for producing an adsorbent for removing harmful gases, comprising the step of impregnating 2 to 6 parts by weight of copper oxide based on 100 parts by weight of activated carbon and 0.1 to 1 part by weight of silver oxide based on 100 parts by weight of activated carbon with the impregnation composition.
delete The method of claim 5, wherein the impregnating composition further includes an organic acid, and the impregnating step further comprises acid treating the activated carbon with the organic acid.