KR102146628B1 - Adsorbent for removing acidic gas and Method for preparing the same - Google Patents

Abstract

The present invention relates to a method for manufacturing an adsorbent, which forms a carrier having a mesoporous pore in a micro-sized pore bonding structure by forcibly inducing pores by adding a surfactant in a state in which natural zeolite, having a small specific surface area and thus having a low value, is dissolved in an aqueous alkali solution, and by inducing bonding with activated carbon powder, thereby capable of increasing pores and a specific surface area to increase acidic gas removal efficiency, as well as increasing economic feasibility and the strength of the manufactured adsorbent.

Description

Adsorbent for removing acidic gas and method for preparing the same {Adsorbent for removing acidic gas and method for preparing the same}

The present invention has a mesoporous pore in a micro-sized pore-bonded structure by forcibly inducing pores by adding a surfactant in a state in which natural zeolite, which has a small specific surface area, and having a low value in an aqueous alkali solution, is forcibly formed. The present invention relates to a method of manufacturing an adsorbent capable of increasing the pores and specific surface area, thereby improving the acidic gas removal efficiency by forming a carrier, as well as achieving economic efficiency and increasing the strength of the prepared adsorbent.

In various electronic product manufacturing processes such as semiconductor manufacturing processes, various types of acid gases are discharged. When the acid gas is discharged into the atmosphere as it is, it is harmful to the human body and causes environmental pollution. Therefore, as in the following patent document, an acidic gas is provided using a purification apparatus using an adsorbent.

<Patent Literature>

Patent Publication No. 10-1395275 (registered on May 08, 2014) "Waste gas purification method and purification device"

However, conventional adsorbents have a problem in that they do not effectively treat acidic gases such as HCl and Cl2 while promoting economic efficiency.

The present invention was devised to solve the above problems,

The present invention has a mesoporous pore in a micro-sized pore-bonded structure by forcibly inducing pores by adding a surfactant in a state in which natural zeolite, which has a small specific surface area of low value, is dissolved in an aqueous alkali solution. The purpose of this is to provide a method for manufacturing an adsorbent capable of increasing the porosity and specific surface area, thereby improving the acidic gas removal efficiency, as well as promoting economic efficiency and increasing the strength of the prepared adsorbent. have.

In addition, the present invention can increase the strength of the prepared adsorbent by allowing sufficient binder action to occur, improve the dispersibility of alkali metals, and perform additional ionization for acidic gas in the reaction process, and effectively disperse heat, An object thereof is to provide a method of manufacturing an adsorbent with improved acid gas removal efficiency.

The present invention is implemented by an embodiment having the following configuration in order to achieve the above object.

According to an embodiment of the present invention, a method for preparing an adsorbent according to the present invention includes a step of forming a carrier mixture by mixing a basic metal chloride and a carrier to form a carrier mixture, and mixing the carrier mixture with an aqueous alkali solution to form a carrier solution. And a mixed solution forming step of forming a mixed solution by adding and reacting the carrier solution into a surfactant solution.

According to another embodiment of the present invention, in the method for preparing an adsorbent according to the present invention, activated carbon and natural zeolite are used as the carrier.

According to another embodiment of the present invention, in the method for preparing an adsorbent according to the present invention, the basic metal chloride is at least one selected from the group consisting of zinc chloride, magnesium chloride, and calcium chloride, and the activated carbon is the basic metal. 80 to 120 parts by weight per 100 parts by weight of chloride is used, and the natural zeolite is characterized in that 80 to 120 parts by weight per 100 parts by weight of the basic metal chloride are used.

According to another embodiment of the present invention, in the method for preparing the adsorbent according to the present invention, a mixture of 8 to 10 g of zinc chloride per 1 g of magnesium chloride is used as the basic metal chloride, and in the step of forming the carrier solution, iron oxide is used. An additionally mixed aqueous alkali solution is used, and the iron oxide is characterized in that 100 parts by weight of the basic metal chloride and 15 to 25 parts by weight are used.

According to another embodiment of the present invention, in the step of forming the mixed solution in the method for preparing an adsorbent according to the present invention, the carrier solution is added to a surfactant solution and reacted at a temperature of 80 to 120°C for 2 to 4 hours. To form a mixed solution, the surfactant solution is formed by mixing 1800 to 2500 parts by weight per 100 parts by weight of basic metal chloride, 80 to 120 g of surfactant per 1 liter of distilled water, and the surfactant is TTAB, DTAB, CTAB, It is characterized in that any one or more selected from the group consisting of Tween-20, Tween-40 and Tween-80 is used.

According to another embodiment of the present invention, in the mixing solution forming step in the method for preparing the adsorbent according to the present invention, the carrier solution is added dropwise to the surfactant solution.

According to another embodiment of the present invention, in the method for preparing an adsorbent according to the present invention, by adding an acetic acid solution to the mixed solution, adjusting the pH to 9 to 10 and reacting at a temperature of 80 to 120°C for 2 to 4 hours. It characterized in that it comprises a pH adjustment step of obtaining a thickened gelled dried product, and a dough forming step of forming a dough by mixing the dried product with an aqueous solution of zinc oxide and calcium carbonate.

According to another embodiment of the present invention, in the method for preparing the adsorbent according to the present invention, the zinc oxide is used in an amount of 80 to 120 parts by weight per 100 parts by weight of the basic metal chloride, and the aqueous calcium carbonate solution is 100 parts by weight of the basic metal chloride. 50 to 200 parts by weight are used per part by weight, and it is characterized in that it has a 2 to 3 molar concentration.

According to another embodiment of the present invention, in the dough forming step in the preparation method of the adsorbent according to the present invention, zinc hydrogen carbonate is additionally mixed with zinc oxide, and the zinc hydrogen carbonate is 30 per 100 parts by weight of basic metal chloride. It is characterized in that to 50 parts by weight are used.

According to another embodiment of the present invention, in the dough forming step in the method for preparing an adsorbent according to the present invention, nanodiamonds are additionally mixed with the calcium carbonate aqueous solution, and the nanodiamonds are added to 100 parts by weight of basic metal chloride. It is characterized in that 1 to 3 parts by weight are used.

According to another embodiment of the present invention, the adsorbent according to the present invention is characterized in that it is prepared by the method of any one of claims 1 to 10.

According to another embodiment of the present invention, the adsorbent according to the present invention is characterized in that it removes acidic gases.

The present invention can obtain the following effects by the configuration, combination, and use relationship that will be described below with the present embodiment.

The present invention has a mesoporous pore in a micro-sized pore-bonded structure by forcibly inducing pores by adding a surfactant in a state in which natural zeolite, which has a small specific surface area, and having a low value in an aqueous alkali solution, is forcibly formed. Since the carrier is formed, the pores and specific surface area can be increased to improve the acidic gas removal efficiency, as well as economical efficiency.

In addition, the present invention can increase the strength of the prepared adsorbent by allowing sufficient binder action to occur, improve the dispersibility of alkali metals, and perform additional ionization for acidic gas in the reaction process, and effectively disperse heat, There is an effect that the acid gas removal efficiency can be improved.

1 is a SEM image of an adsorbent according to an embodiment of the present invention.

Hereinafter, an adsorbent for removing an acidic gas and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings. Unless otherwise defined, all terms in this specification are the same as the general meaning of the terms understood by those of ordinary skill in the art to which the present invention belongs, and in case of conflict with the meaning of terms used herein, In accordance with the definitions used in the specification. In addition, detailed descriptions of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted. Throughout the specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

Referring to FIG. 1, a method of preparing an adsorbent for removing acidic gas according to an embodiment of the present invention is described with reference to FIG. 1, wherein the method of preparing the adsorbent for removing acidic gas is a carrier mixture in which a basic metal chloride and a carrier are mixed to form a carrier mixture. A forming step, a carrier solution forming step of mixing the carrier mixture with an aqueous alkali solution to form a carrier solution, a mixed solution forming step of adding the carrier solution to a surfactant solution and reacting to form a mixed solution, and the mixed solution A pH adjustment step of adjusting the pH to 9 to 10 by adding an acetic acid solution and drying to obtain a dried product, a dough forming step of forming a dough by mixing an aqueous zinc oxide and calcium carbonate solution with the dried product, and molding the dough And then drying to form an adsorbent. The adsorbent prepared by the above manufacturing method removes the acidic gas, and the acidic gas includes hydrogen chloride (HF, HCl, HBr, etc.), and a lubricant gas (Cl ₂ , F ₂ , ClF _3, etc.).

The step of forming a carrier mixture is a step of forming a carrier mixture by mixing a basic metal chloride and a carrier. The basic metal chloride may be used in the form of a powder, and preferably has an average diameter of 0.5 to 200 μm. The basic metal chloride is preferably at least one selected from the group consisting of zinc chloride, magnesium chloride, and calcium chloride, and more preferably, 8 to 10 g of zinc chloride per 1 g of magnesium chloride are used in combination. The carrier may be used in the form of a powder, and coal-based activated carbon and zeolite are preferably used. The coal-based activated carbon is used in an amount of 80 to 120 parts by weight per 100 parts by weight of the basic metal chloride, has a total pore volume of 0.1 to 0.4 cm ³ /g, has an average pore size of 2 to 10 nm, and has an average pore size of 100 to 400 m ² /g. It is desirable to have a specific surface area. The zeolite may be a natural zeolite, 80 to 120 parts by weight per 100 parts by weight of the basic metal chloride is used, has a total pore volume of 0.1 to 0.5 cm ³ /g, has an average pore size of 2 to 20 nm, and 100 to It is preferred to have a specific surface area of 150 m ² /g.

The carrier solution forming step is a step of forming a carrier solution by mixing the carrier mixture with an aqueous alkali solution, and the alkali aqueous solution is used in an amount of 2000 to 3000 parts by weight per 100 parts by weight of a basic metal chloride, and 200 to 600 g sodium hydroxide per 1 liter of distilled water. It is preferably formed by mixing.

The mixed solution forming step is a step of forming a mixed solution by adding the carrier solution to a surfactant solution and reacting at a temperature of 80 to 120°C for 2 to 4 hours, and the surfactant solution is 1800 per 100 parts by weight of a basic metal chloride. To 2500 parts by weight, and preferably formed by mixing 80 to 120 g of surfactant per 1 L of distilled water, and the surfactant is TTAB (tetradecyl trimethyl ammonium bromide), DTAB (dodecyl trimethyl ammonium bromide), CTAB (cetyl trimethyl ammonium bromide) , Tween-20 (polyoxyethylene (20) sorbitan monolaurate), Tween-40 (polyoxyethylene (40) sorbitan monopalmitate), and Tween-80 (polyoxyethylene (80) sorbitan monooleate) Any one or more selected from the group consisting of may be used. When the carrier solution and the surfactant solution are mixed at the same time, the bone grain structure of the carrier is damaged and rearrangement is not performed uniformly, so that basic metals are not dispersed, resulting in a sintering phenomenon, which may degrade the adsorption performance, thus forming the mixed solution. In the step, the carrier solution is added drop by drop to the surfactant solution. The larger the specific surface area of the carrier, the higher the efficiency of physical adsorption, the greater the loading amount of the basic metal, thereby increasing the chemical adsorption efficiency, and thus the acidic gas is more effectively removed.The method of manufacturing the adsorbent has a smaller specific surface area. In a state of dissolving a low-value natural zeolite in an aqueous alkali solution, a surfactant is added to forcibly induce pores to be formed, and to bind with the activated carbon powder, thereby having mesoporous pores in a micro-sized pore-binding structure (i.e., developed pores). Eggplant) by forming a carrier, it is possible to increase the pores and specific surface area. On the other hand, when only activated carbon is used as a carrier, the strength of the prepared adsorbent decreases.In the method of preparing the adsorbent, a surfactant is added in a state in which natural zeolite is dissolved in an aqueous alkali solution to forcibly induce pores to be formed, and to bind with the activated carbon powder. As a result, it is possible to increase the strength as well as increase the specific surface area of the prepared adsorbent. In the case of using an aqueous alkali solution in which iron oxide is additionally mixed in the mixed solution forming step, the acidic gas removal efficiency can be further improved by further increasing dispersibility in the carrier of the basic metal (zinc, magnesium, calcium, etc.). The iron oxide is preferably used in an amount of 15 to 25 parts by weight of 100 parts by weight of a basic metal chloride.

The pH adjusting step is a step of adding an acetic acid solution to the mixed solution to adjust the pH to 9 to 10 and reacting at a temperature of 80 to 120°C for 2 to 4 hours to obtain a thick gelled dried product. When the pH of the dried product is less than 9, the acidic gas removal efficiency decreases, and when the pH of the dried product is greater than 10, the skeleton structure of the carrier is collapsed by strong alkali, and the performance of the adsorbent decreases.

The dough forming step is a step of forming a dough by mixing an aqueous solution of zinc oxide and calcium carbonate with the dried product, wherein the zinc oxide serves as a binder, and 80 to 120 parts by weight per 100 parts by weight of the basic metal chloride are used. desirable. Since the calcium carbonate aqueous solution is used, the strength of the adsorbent is increased, so that the calcium carbonate aqueous solution is used in an amount of 50 to 200 parts by weight per 100 parts by weight of the basic metal chloride, and preferably has 2 to 3 molar concentration. In the dough forming step, when zinc hydrogen carbonate (Zn(HCO ₃ ) ₂ ) is additionally used, hydrogen halide and activator gas are additionally ionized by moisture generated in the reaction process, and nanodiamonds are added to the calcium carbonate aqueous solution. When is further mixed, heat is effectively dispersed during the reaction process (the adsorbent reacts with a high-temperature acid gas and the adsorption process is exothermic, so if the temperature in the adsorbent is not uniform, the adsorption reaction efficiency decreases and the adsorbent may be damaged. ), improves acid gas removal efficiency. The zinc hydrogen carbonate is preferably used in an amount of 30 to 50 parts by weight per 100 parts by weight of the basic metal chloride, and the nanodiamond increases the thermal conductivity of the adsorbent so that it has a uniform temperature throughout, and based on 100 parts by weight of the basic metal chloride. It is preferred that 1 to 3 parts by weight are used.

The drying step is a step of forming an adsorbent by molding and drying the dough to form an adsorbent. For example, an adsorbent may be prepared in a pellet form using an extrusion molding machine, and an adsorbent may be prepared in a spherical shape using a rotary molding machine.

Another embodiment of the present invention relates to an adsorbent prepared by the method for producing the adsorbent.

Hereinafter, the present invention will be described in more detail through examples. However, these are only for describing the present invention in more detail, and the scope of the present invention is not limited thereto.

<Example 1> Preparation of adsorbent

1. Example 1

(1) A carrier mixture was prepared by mixing 50 g of basic metal chloride (45 g of ZnCl ₂ ·6H ₂ O and 5 g of MgCl ₂ ·6H ₂ O), 50 g of coal-based activated carbon and 50 g of natural zeolite, and 400 g of sodium hydroxide was dissolved in 1000 ml of distilled water and alkali. An aqueous solution was prepared, and the carrier mixture and an aqueous alkali solution were mixed and stirred for 1 hour to prepare a carrier solution.

(2) 100 g of CTAB was mixed and stirred in 1000 ml of distilled water to obtain a surfactant solution, and the carrier solution was added drop by drop to the surfactant solution, stirred for 1 hour, and reacted in an oven at 100° C. for 3 hours. After adding an acetic acid solution to a pH of 10, it was reacted in an oven at 100° C. for 3 hours. Thereafter, 50 g of zinc oxide was added as a binder, and an aqueous calcium carbonate solution having a concentration of 2.5 mol was mixed to form a dough, and the dough was molded into a spherical shape using a rotary molding machine, and dried at 100° C. to form an adsorbent.

2. Example 2

An adsorbent was formed in the same manner as in Example 1 except that TTAB was used instead of CTAB.

3. Example 3

An adsorbent was formed in the same manner as in Example 1 except that 1100 ml of distilled water was used instead of the surfactant solution.

4. Example 4

An adsorbent was formed in the same manner as in Example 1 except that 1400 ml of distilled water was used instead of the aqueous alkali solution.

5. Example 5

The adsorbent was formed in the same manner as in Example 1 except that the carrier solution was not added dropwise to the surfactant solution and the entire carrier solution was added to the surfactant solution at once.

6. Example 6

₂ · 6H ₂ O 45g and ZnCl ₂ · 6H ₂ O 5g instead of MgCl ₂ · 6H ₂ O 50g The ZnCl were formed and the adsorbent in the same manner as one of Example 1, except that the other conditions used in the.

7. Example 7

Except that CaCl ₂ ·2H ₂ O was used instead of ZnCl ₂ ·6H ₂ O, an adsorbent was formed under the same conditions as in Example 1 1.

8. Example 8

An adsorbent was formed in the same manner as in Example 1 except that the same amount of distilled water was used instead of the aqueous calcium carbonate solution.

9. Example 9

An adsorbent was formed in the same manner as in Example 1 except that 10 g of iron oxide was additionally used in the aqueous alkali solution.

10. Example 10

Except that 50 g of zinc oxide and 20 g of zinc hydrogen carbonate were additionally used, an adsorbent was formed in the same manner as 9 of Example 1.

11. Example 11

An adsorbent was formed in the same manner as in Example 1, except that 1 g of nano diamonds (using PL-D-G01) was additionally used in the calcium carbonate aqueous solution.

<Example 2> Physical properties confirmation

1. The specific surface area (m ² /g) of the adsorbents prepared in Example 1 1 to 5 and 11 was measured using a BET apparatus (specific surface area analyzer), and the results are shown in Table 1. In addition, the adsorbents prepared in Example 1 1 and 3 were measured by SEM, and the results are shown in Fig. 1 (Fig. 1A is an SEM image of the adsorbent prepared in Example 1, Figure 1 (b) is a SEM image of the adsorbent prepared in Example 1 3).

2. Looking at Table 1, it can be seen that the specific surface area of the adsorbents prepared in Example 1 3 to 5 was significantly smaller than that of the adsorbents prepared in Example 1, 2 and 11, and no surfactant was used. Or, when the alkali aqueous solution is not used when the carrier solution is formed, or when the carrier solution and the surfactant solution are mixed together, it can be seen that the specific surface area of the prepared adsorbent is small, and in the adsorbents prepared in Example 1 1 and 2 In comparison, the specific surface area of the adsorbent prepared in Example 1 11 was small, but there was little difference, so it was found that the effect on the untargeted by the additive added to impart a specific function after the formation of mesoporous pores was small. have. In addition, looking at Figure 1, the adsorbent prepared in Example 1 1 has mesoporous pores (pore diameter of 3.53 nm), whereas the adsorbent prepared in Example 1 3 has a smooth surface area. It can be seen that the adsorbent prepared in Example 1 of 1 had a mesoporous pore structure and thus increased specific surface area.

Example 1-1 Example 1-2 Example 1-3 Example 1-4 Example 1-5 Example 1-11 Specific surface area (m ² /g) 512 498 110 190 200 459

<Example 3> Acid gas treatment efficiency evaluation

1. The adsorption removal experiment was carried out by putting 20 ml of each of the adsorbents prepared in Examples 1 to 11 in a cylindrical reactor made of glass having an inner diameter of 25 mm and a height of 80 mm. Hydrogen chloride (HCl) standard gas (manufactured with 998umol/mol N ₂ Balance) was continuously flowed by maintaining a constant flow rate of 1LPM, and the gas flowing out after the reaction was analyzed through FT-IR (MIDAC, Korea). When the concentration of reached 10 ppm, it was reported as the time of destruction, and the amount of HCl gas removed per 1 L of adsorbent was evaluated as adsorption performance, and the results are shown in Table 2. In addition, chlorine (Cl ₂ ) standard gas (manufactured with 1,012 umol/mol N ₂ Balance) was kept constant at a flow rate of 5 LPM, and the gas flowed out after the reaction was collected in a Tedler bag and a detection tube (gas Tec, Japan), and when the concentration of the collected gas reaches 10 ppm, the time of destruction was reported, and the amount of Cl ₂ removed per 1 L of adsorbent was evaluated as adsorption performance, and the results are shown in Table 2.

2. Looking at Table 2, as confirmed in Example 2, it can be seen that the adsorbents prepared in 3 to 5 of 1 of Example 1 with a small specific surface area have low acid gas removal efficiency, and are prepared in Example 1 of 1 The resulting adsorbent can be confirmed to have better acid gas removal efficiency than the adsorbents prepared in Example 1 6 and 7, so that Zn has better acid gas removal efficiency than Ca, and when Mg is added than when Zn alone is used, the cocatalyst It can be seen that it improves the acid gas removal efficiency by performing the role of In addition, the adsorbents prepared in Example 1 9 to 11 have better acid gas removal efficiency than the adsorbent prepared in Example 1 1, which improves the dispersibility of alkali metals when iron oxide is used, and zinc hydrogen carbonate is used. In this case, the hydrogen halide and the lubricant gas are further ionized by the moisture generated in the reaction process, and when nanodiamonds are used, heat is effectively dispersed, thereby improving the acid gas removal efficiency.

Example HCl adsorption Cl ₂ adsorption Breaking time (min) Adsorption amount (L/L) Breaking time (min) Adsorption amount (L/L) One 180 44 115 29 2 175 46 119 26 3 50 15 25 12 4 70 23 33 15 5 68 25 31 14 6 150 38 99 23 7 171 41 105 24 8 175 42 110 26 9 220 53 133 35 10 309 79 200 41 11 400 98 270 53

<Example 4> Evaluation of compressive strength

1. The compressive strength (Kgf) was measured for the adsorbents prepared in Example 1 1 and 8. The compressive strength of the adsorbent prepared in Example 1 1 was 6.4, and the compressive strength of the adsorbent prepared in Example 1 1 was 2.7.

2. It can be seen that the adsorbent prepared in Example 1 of 1 has a higher compressive strength than the adsorbent prepared in Example 1 of 8, so when a calcium carbonate aqueous solution is used, sufficient binder action occurs to improve the strength of the adsorbent. Can be seen.

In the above, the applicant has described the preferred embodiments of the present invention, but such embodiments are only one embodiment embodying the technical idea of the present invention, and any change or modification of the present invention as long as the technical idea of the present invention is implemented. It should be construed as falling within the scope.

Claims (12)

A carrier mixture formation step of mixing a basic metal chloride and a carrier to form a carrier mixture, a carrier solution formation step of mixing the carrier mixture with an aqueous alkali solution to form a carrier solution, and adding the carrier solution to a surfactant solution and reacting A mixed solution forming step of forming a mixed solution, and an acetic acid solution is added to the mixed solution to adjust the pH to 9 to 10 and react at a temperature of 80 to 120°C for 2 to 4 hours to obtain a thick gelled dried product. A pH control step to be obtained, and a dough forming step of forming a dough by mixing an aqueous zinc oxide and calcium carbonate solution with the dried product,
Activated carbon and natural zeolite are used as the carrier, 80 to 120 parts by weight of the activated carbon are used per 100 parts by weight of the basic metal chloride, and 80 to 120 parts by weight of the natural zeolite are used per 100 parts by weight of the basic metal chloride,
In the step of forming the carrier solution, an alkaline aqueous solution further mixed with iron oxide is used, and the iron oxide is used in an amount of 15 to 25 parts by weight per 100 parts by weight of the basic metal chloride,
In the dough forming step, zinc hydrogen carbonate is additionally mixed with zinc oxide, and nanodiamonds are further mixed with the calcium carbonate aqueous solution,
The zinc oxide is used at 80 to 120 parts by weight per 100 parts by weight of the basic metal chloride, the calcium carbonate aqueous solution is used at 50 to 200 parts by weight per 100 parts by weight of the basic metal chloride, and the zinc hydrogen carbonate is used per 100 parts by weight of the basic metal chloride. 30 to 50 parts by weight is used, and the nano-diamond is 1 to 3 parts by weight per 100 parts by weight of the basic metal chloride. delete The method of claim 1,
The basic metal chloride is a method for producing an adsorbent, characterized in that at least one selected from the group consisting of zinc chloride, magnesium chloride, and calcium chloride is used. The method of claim 3,
The basic metal chloride is a method for producing an adsorbent, characterized in that a mixture of 8 to 10 g of zinc chloride per 1 g of magnesium chloride is used. The method of claim 4,
In the mixed solution forming step, the carrier solution is added to a surfactant solution and reacted at a temperature of 80 to 120° C. for 2 to 4 hours to form a mixed solution,
The surfactant solution is formed by mixing 1800 to 2500 parts by weight per 100 parts by weight of basic metal chloride, and 80 to 120 g of surfactant per 1 liter of distilled water,
The surfactant is a method of producing an adsorbent, characterized in that at least one selected from the group consisting of TTAB, DTAB, CTAB, Tween-20, Tween-40 and Tween-80 is used. The method of claim 5,
In the mixed solution forming step, the carrier solution is added drop by drop to the surfactant solution. delete delete delete delete delete delete

Images