KR101863289B1 - Manufacturing method of PEI particle crosslinked with glutaraldehyde for adsorbing carbon dioxide, and PEI particle crosslinked with glutaraldehyde manufactured thereby - Google Patents

Abstract

The present invention relates to a process for producing a polyethyleneimine emulsion in the form of water-in-oil (W / O) by adding a polyethyleneimine (PEI) solution as a water-soluble dispersed phase to a continuous phase prepared by mixing an organic solvent and an emulsifier; A second step of adding glutaraldehyde to the polyethyleneimine emulsion to prepare a polyethyleneimine particle crosslinked with glutaraldehyde by proceeding a cross-linking reaction between the amino group of the polyethyleneimine contained in the emulsion and the aldehyde group of glutaraldehyde; And a third step of drying the polyethyleneimine particles crosslinked with the glutaraldehyde. The present invention also relates to a method for producing glutaraldehyde crosslinked polyethyleneimine particles. The PEI particles of the present invention have the advantages of selective carbon dioxide absorption of conventional liquid amines and can compensate for the disadvantages of corrosion by a dry method and complicated processes and dissolution phenomena which are disadvantages of hybrid organic and inorganic materials.

Description

[0001] The present invention relates to a method for producing crosslinked PEI particles for glutaraldehyde for carbon dioxide adsorbent, and to a method for producing glutaraldehyde crosslinked PEI particles, which comprises preparing crosslinked glutaraldehyde (PEI)

The present invention relates to a process for producing a carbon dioxide adsorbent characterized in that glutaraldehyde is added to a polyethyleneimine (PEI) emulsion to produce polyethyleneimine particles in which glutaraldehyde is crosslinked.

In order to reduce carbon dioxide, alternative energy (renewable energy) is used, energy efficiency of fossil fuel combustion system is improved, and carbon capture and storage (CCS) As the most ideal way to reduce carbon dioxide in a short period of time while keeping it, the competition of CCS technology development is accelerated mainly in developed countries.

CO2 capture technology can be roughly divided into pre-combustion capture technology, oxy-fuel combustion technology, and post-combustion capture technology. Pre-combustion capture technology converts carbon or natural gas into hydrogen and carbon dioxide and then recovers carbon dioxide. It collects high-concentration carbon dioxide at high pressure and recovers at low pressure, so it is easy to recover carbon dioxide. Oxyfuel combustion technology is a technology that uses pure oxygen as an oxidizer to increase thermal efficiency. It is currently in research stage to capture pure carbon dioxide by condensing water vapor in gas mixed with carbon dioxide and water vapor generated during combustion. The post-combustion capture technology is the most commercialized technology currently used to separate and capture carbon dioxide generated after combustion such as industrial processes.

In the case of post-combustion capture technology, various mixed gases exist in the exhaust gas through combustion, and a process for separating carbon dioxide is required. Methods for separating carbon dioxide from a mixed gas include membrane separation, absorption, and adsorption. The membrane separation method is a technique of selectively separating carbon dioxide by permeating a mixed gas, which is simple in process and consumes little energy, but is expensive and disadvantageous in high-capacity processing and durability. The absorption method is advantageous in that it absorbs carbon dioxide selectively by using ammonia water and a liquid amine type material (MEA, DEA, TEA, etc.). However, when the apparatus is corroded or absorbed, Is consumed. The adsorption method is a method of adsorbing carbon dioxide using zeolite (13X, 4A, ZSM-5, etc.), activated carbon and hybrid organic hybrid materials (impregnated with amine-based material such as Fumed-Silica, MCM and SBA) There are adsorption and chemical adsorption. Zeolite and activated carbon are physically adsorbed by van der Waals force, and the process is simple and energy efficient. However, the ability of adsorbing carbon dioxide at high temperature is drastically decreased, is affected by moisture, and is lower in carbon dioxide adsorption than absorption method . The organic hybrid composite material has an amine group, which has advantages of liquid amine (selective adsorption of carbon dioxide, high carbon dioxide absorption ability even at low carbon dioxide concentration), and is not influenced by moisture more than physically adsorbed material.

On the other hand, the organic hybrid composite material can be prepared by impregnation using a simple impregnation method and a silane coupling method. Simple impregnation can be easily performed by impregnating the support with physically amine-based materials. However, the possibility of leaking or washing out under moisture can be great. The covalent bonding method is strong against moisture, There is a disadvantage in that it is difficult to carry out the reaction with the amine-based material after the reforming and the absorption ability is lower than that of the simple impregnation, and the organic component only operates at a relatively low temperature and is difficult to mass-produce.

Accordingly, the present inventors have manufactured a new carbon dioxide dry adsorbent having a nanometer size by using inverse emulsion technique and cross-linking polymerization from polyethyleneimine (PEI), and adjusted the concentrations of B-PEI and cross-linking agent of various molecular weights, The results of the comparative analysis of the structure, properties, thermal stability and carbon dioxide adsorption / desorption performance show that it has the advantages of selective carbon dioxide absorption of the conventional liquid amine, and the disadvantages of the corrosion by dry method and complicated process and dissolution It has been confirmed that spherical nanometer sized particles capable of complementing the phenomenon can be prepared by reverse phase emulsification technique and crosslinking polymerization, and the present invention has been completed.

KR 2012-0004580 A

It is an object of the present invention to provide a process for the selective adsorption of carbon dioxide of a liquid amine having the advantages of the selective absorption of carbon dioxide by using a conventional method and a spherical nanometer size particle which can compensate for the disadvantage of corrosion by a dry process, And a method for manufacturing the same.

A first aspect of the present invention is a method for producing a polyethyleneimine emulsion in the form of a water-in-oil (W / O) by adding a polyethyleneimine (PEI) solution as a water-soluble dispersed phase to a continuous phase prepared by mixing an organic solvent and an emulsifier step; A second step of adding glutaraldehyde to the polyethyleneimine emulsion to prepare a polyethyleneimine particle crosslinked with glutaraldehyde by proceeding a cross-linking reaction between the amino group of the polyethyleneimine contained in the emulsion and the aldehyde group of glutaraldehyde; And a third step of drying the polyethyleneimine particles crosslinked with glutaraldehyde. The present invention also provides a method for producing glutaraldehyde crosslinked polyethyleneimine particles.

Hereinafter, the present invention will be described in detail.

The present invention is characterized by producing a PEI emulsion in which a PEI solution is dispersed as a water-soluble dispersed phase on a continuous phase.

The organic solvent for the continuous phase may be an aliphatic organic solvent, an aromatic organic solvent, a paraffinic organic solvent, or the like, but is not limited thereto.

The continuous phase emulsifier may be, but is not limited to, polyglycerol ester, polyoxyethylene ester, polyoxyethylene fatty acid ether, polyglycerol ester, polyglycerol ether, or mixtures thereof. Preferably, a homologous sorbitan fatty acid ester (Span series) can be used. The amount of the emulsifier to be used is preferably 2 to 10% by weight of the total weight of the continuous phase. When the amount of the emulsifier is less than 2% by weight, micelles can not be formed and it is difficult to maintain the emulsified state. When the amount of the emulsifier is more than 10% by weight, phase separation may occur and a washing process may be required.

The polyethyleneimine used in the production process of the present invention may be branched polyethyleneimine having a weight average molecular weight of 2,000 to 70,000.

The PEI solution as the water-soluble dispersion phase may be a solution containing polyethyleneimine (PEI) and deionized water. The content of PEI in the PEI solution is preferably 15 to 25% by weight. When the concentration of PEI is less than 15% by weight, the carbon dioxide adsorption capability may deteriorate. Particle formation (emulsion formation) may be difficult due to a low concentration of PEI. When the concentration of PEI is more than 25% by weight, PEI emulsion is not formed .

In addition, the present invention relates to a method for producing glutaraldehyde by reacting a PEI polymer with a glutaraldehyde having an aldehyde group in a short-term end by adding glutaraldehyde to the PEI emulsion prepared by reversed-phase emulsification, Thereby producing crosslinked PEI particles.

The present inventors analyzed the chemical structural change of the crosslinked PEI particles through FT-IR analysis. As a result, peaks at 1656 cm ^-1 (C = N stretching) characteristic of Schiff's reaction which did not exist in pure PEI were generated after the crosslinking reaction and 3357 cm < ^-1 > (NH stretching) peak is shifted to 3400 cm < ^-1 > after the reaction.

In the present invention, the reaction molar ratio of polyethyleneimine (PEI): glutaraldehyde is preferably 1: 0.2 to 0.5. When the reaction molar ratio is less than 1: 0.2, particle formation may be difficult, and when it is more than 1: 0.5, solid lumps larger than particles may be formed.

The third step in which the glutaraldehyde-crosslinked PEI particles are dried may be a step of removing residual organic solvent and unreacted residue through centrifugation and drying. For example, after the second step, the residual oil and unreacted residues may be removed by centrifugation three to four times using isopropylalcohol, followed by drying in a vacuum oven for 12 hours.

A second aspect of the present invention provides PEI particles prepared according to the first aspect of the present invention, wherein the glutaraldehyde is crosslinked.

The crosslinked PEI particles produced according to the present invention are characterized by a final decomposition temperature of 450 ° C or higher. Therefore, the final decomposition temperature is advantageous because it exhibits higher thermal stability than PEI having a temperature of about 400 ° C.

The diameter of the crosslinked PEI particles prepared according to the present invention may be 200 nm to 15 탆, preferably 200 nm to 5 탆. The crosslinked PEI particles prepared according to the present invention did not use any inorganic particles such as SiO ₂ and were produced by inducing a small amount of crosslinking reaction within a range that does not impair the inherent CO ₂ adsorption property of PEI. Accordingly, the carbon dioxide adsorbent of the present invention exhibits a high CO ₂ adsorption performance because it contains a relatively large amount of amine functional groups at the same unit weight, as compared with the adsorbent impregnated in conventional inorganic particles, .

Further, a third aspect of the present invention provides a carbon dioxide adsorbent comprising the polyethylene imine particles of the second aspect of the present invention.

The glutaraldehyde crosslinked PEI particles prepared according to the present invention are included in the carbon dioxide adsorbent, and can exhibit a higher CO ₂ adsorption amount than pure PEI.

The glutacaldehyde-crosslinked PEI particles prepared according to the present invention have the advantages of the selective carbon dioxide absorption of the conventional liquid amine and can be used in a dry process to compensate for the disadvantages of corrosion and complicated processes and dissolution phenomena which are disadvantages of hybrid organic and inorganic materials . The glutaraldehyde crosslinked PEI particles prepared according to the present invention may exhibit a higher CO ₂ adsorption amount than the pure PEI particles.

1 is a schematic diagram of a process for producing PEI particles through reversed phase emulsification.
2 is an FE-SEM photograph of 2K-M25, 2K-37.5, and 2K-M50, PEI particles prepared according to the present invention.
3 is an FE-SEM photograph of 25K-M25, 25K-M37.5 and 25K-M50 PEI particles prepared according to the present invention.
4 is an FE-SEM photograph of 70K-M25, 70K-M37.5 and 70K-M50 PEI particles prepared according to the present invention.
FIG. 5 is a graph showing particle size analysis of 2K-M25, 2K-37.5 and 2K-M50, PEI particles prepared according to the present invention.
FIG. 6 is a graph of particle size analysis of 25K-M25, 25K-M37.5 and 25K-M50, PEI particles prepared according to the present invention.
7 is a graph of particle size analysis of 70K-M25, 70K-M37.5 and 70K-M50, PEI particles prepared according to the present invention.
8 is an FT-IR spectrum of (a) PEI 2K, (b) 2K-M25, (c) 2K-M37.5 and (d) 2K-M50.
9 is an FT-IR spectrum of (a) PEI 25K, (b) 25K-M25, (c) 25K-M37.5 and (d) 25K-M50.
10 is an FT-IR spectrum of (a) PEI 70K, (b) 70K-M25, (c) 70K-M37.5 and (d) 70K-M50.
Fig. 11 shows the thermogravimetric analysis results of PEI 2K, 2K-M25, 2K-M37.5 and 2K-M50.
12 shows the results of thermogravimetric analysis of PEI 25K, 25K-M25, 25K-M37.5 and 25K-M50.
13 shows the thermogravimetric analysis results of PEI 70K, 70K-M25, 70K-M37.5 and 70K-M50.
Figure 14 compares the dynamic CO ₂ adsorption after exposure to PEI particles of Table 3 at 75 ° C for 180 minutes.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

<Material>

=2,000, Da; 50wt% solution in water, Sigma-Aldrich), 25K(

=25,000, Sigma-Aldrich), 70K(

=70,000, Da; 30wt% solution in water, Junsei)을 구입하여 사용하였다. 연속상으로 중질 광유(Daejung)를 사용하였고, 분산상으로 탈이온수((DI water, Dream Plus II, JEIO-TECH)를 사용하였다. 계면활성제로는 span 80(Sorbitan Monooleate, Sigma-Aldrich)을 사용하였고, 가교제로 glutaraldehyde (25 wt% solution in water, Junsei)를 사용하였다.The branched polyethylenimine (PEI) used in the particle preparation has three different average molecular weights, 2K

= 2,000, Da; 50 wt% solution in water, Sigma-Aldrich), 25K (

= 25,000, Sigma-Aldrich), 70K (

= 70,000, Da; 30wt% solution in water, Junsei) were purchased and used. (DI water, Dream Plus II, JEIO-TECH) was used as the dispersed phase, span 80 (Sorbitan Monooleate, Sigma-Aldrich) was used as the surfactant, , Glutaraldehyde (25 wt% solution in water, Junsei) was used as a crosslinking agent.

Example 1: Preparation of PEI particles by reversed phase emulsification method

60 g of mineral oil and Span-80 were added to a 250 mL beaker and stirred at 200 rpm for 5 minutes to prepare a continuous phase. Span-80 was added in an amount of 5% by weight based on the total weight of the continuous phase. The PEI solution was dissolved in deionized water to prepare a 20 wt% PEI solution. 40 g of PEI solution was added to the continuous phase in which Span-80 was dissolved, and dispersed at 5000 rpm for 3 minutes using a homogenizer to obtain water- Emulsion of the form. The obtained W / O emulsion was transferred to a 600 mL beaker and stirred at 200 rpm using a magnetic stirrer. Then, the glutaraldehyde solution was added to 0.2 mL · min ^. (UniSpense PRO, Wheaton) through a latex tube having an inner diameter of 3 mm at a speed of ¹ mm / sec and crosslinked at 25 ° C for 24 hours to prepare cross-linked PEI particles. The molar ratio of PEI to glutaraldehyde was adjusted according to the following Table 1. Then, the residual oil and unreacted residues were removed by centrifugation three to four times with isopropylalcohol and dried in a vacuum oven for 12 hours. Fig. 1 shows a schematic diagram of the experiment. PEI of different molecular weight was also carried out in the same manner.

Name of sample PEI molecular weight The NH ₂ group (mol) The aldehyde group (mol) in glutaraldehyde Mall / Mall
(%) 2K-M25 2,000 0.0176 0.0044 25 2K-M37.5 2,000 0.0176 0.0066 37.5 2K-M50 2,000 0.0176 0.0088 50 25K-M25 25,000 0.0246 0.0062 25 25K-M37.5 25,000 0.0246 0.093 37.5 25K-M50 25,000 0.0246 0.0123 50 70K-M25 70,000 0.0254 0.0064 25 70K-M37.5 70,000 0.0254 0.0096 37.5 70K-M50 70,000 0.0254 0.0127 50

Experimental Example 1: Morphology analysis of PEI particles

SEM analysis was carried out using the JSM-6701F (JEOL) model to analyze the surface, shape and size of the crosslinked PEI particles according to Example 1. Samples were platinum coated prior to analysis.

Figs. 2 to 4 are FE-SEM photographs of PEI particles according to crosslinking of respective molecular weights. From the photographs of the prepared particles, it was confirmed that the single particle was perfectly spherical. It can be seen that the size is formed to be about 1 탆 or less, and the size is not uniform though dispersed.

It is also known that particles that have collapsed or broken (particles half-and-half rolled or amorphous, etc.) are visible because the cross-linked PEI removes the continuous phase and water through centrifugation It is presumed that the strength is difficult to maintain the structure of the sphere.

Experimental Example 2: Particle size analysis (PSA)

To determine the size and distribution of crosslinked PEI particles, the size of each sample was compared using a mastersizer 2000 model from Malvern and isopropylalcohol as a dispersion medium.

FIGS. 5 to 7 are graphs illustrating the particle size of the PEI particles produced through the PSA. As a result of the particle size analysis, it can be seen that the distribution of 2K and 25K shows a distribution ranging from 200 nm to 2 μm at a small size as shown in an SEM photograph, and at 300 K to 5 μm at 70 K, Of the chain length of the polymer due to the use of PEI.

Experimental Example 3: Analysis of chemical structure of PEI particles

FT-IR analysis was performed using Varian's 660-IR to confirm the presence of PEI and glutaraldehyde reaction and the chemical structure of each polymer structure. The spectrum of 4000-400 cm ^-1 region was analyzed.

FT-IR results of 2K, 25K and 70K PEI and PEI particles prepared according to the present invention are shown in Figs. 8-10.

PEI shows peaks at 3357 cm ^-1 to 3295 cm ^-1 , indicating NH stretching of the primary and secondary amines, with two peaks at the peak of this region indicating primary amines and one secondary amine. 2935 cm ^-1 and 2813 cm ^-1 indicate symmetric and asymmetric CH stretching. 1640 cm ^-1 to 1560 cm ^-1 are NH bending and represent primary and secondary amines. 1465 cm ^-1 indicates CH bending, 1350 cm ^-1 at 1000 cm ^-1 indicates CN stretching, and PEI particles show the same peak.

Comparing peaks of PEI particles to PEI, it can be seen that peaks which were not found in PEI at 1656 cm ^-1 appear in PEI particles. 1656 cm ^-1 is a C = N stretching band. It can be seen that the amine group of PEI and the aldehyde group of glutaraldehyde are the peaks formed by the reaction of Schiff's reaction, and PEI particles are formed by Schiff's reaction. In addition, 3357 cm ^-1 , which is the peak with the primary amine, is chemically transferred to 3400 cm ^-1 at the double peak with increasing cross-linking agent, and the peak shifts to one peak, indicating that the primary amine reacted with glutaraldehyde.

Experimental Example 4: Analysis of thermal stability of PEI particles

By using a thermal stability and a crosslinking degree TA Instrument Inc. thermogravimetric analysis (TGA) Q500 model to evaluate the thermal stability according to the PEI compared to PEI particles using N ₂ gas at a temperature of 100 ℃ ~ 600 ℃ PEI and PEI We investigated the change of mass decrease with particle temperature. FIGS. 11 to 13 show TGA graphs of PEI 2K, 25K and 70K and PEI particles, respectively.

In the case of PEI, mass reduction is observed from 30 ° C to about 160 ° C, which is attributed to the decrease in mass due to physically adsorbed CO ₂ and the decrease in mass due to the evaporation of water in the PEI solution. After that, it gradually decreased to 250 ° C, and mass reduction rapidly occurred from about 300 ° C to 400 ° C, and all of the PEI was decomposed at about 420 ° C.

In the case of PEI particles, mass reduction occurs from 50 ° C to 160 ° C, which is judged to be a decrease in the mass of CO ₂ and water as in PEI. Although the rapid mass reduction began at 300 ° C similar to PEI, it was found that the decomposition rate was slower than that of PEI, and it remained at least 80% even at around 350 ° C. The final decomposition temperature is 450 ° C, which is about 50 ° C higher than that of PEI. This difference is attributed to the increase in thermal stability of PEI due to crosslinking. Thus, it can be seen that PEI particles are thermally more stable than PEI particles. Particularly, the PEI particles of the present invention can be applied to various fields requiring thermal stability because there is almost no reduction in mass even at around 350 ° C.

Experimental Example 5: Specific surface area analysis

When a PEI solution is dissolved in water and a crosslinking agent is added, a network structure is formed due to the crosslinking agent, and a substance having a specific surface area is produced. Likewise, it is assumed that particles made using reversed phase emulsification method and crosslinking reaction have a network structure and particles capable of expanding and contracting to some extent while having fine pores on the surface and inside, Area), but the particles prepared by reversed phase emulsification showed no porosity. The results are shown in Table 2 below.

PEI MW Name of sample Specific surface area (m &lt; 2 &gt; / g)
2,000
2K-M25 5.18 2K-M37.5 4.09 2K-M50 5.01
25,000
25K-M25 6.66 25K-M37.5 6.92 2K-M50 10.2
70,000
70K-M25 4.24 70K-M37.5 4.45 70K-M50 4.09

Experimental Example 6: Analysis of CO ₂ adsorption characteristics according to molecular weight and crosslinking agent concentration of PEI

In order to analyze the CO ₂ adsorption characteristics of polymer structures containing amine groups, mass changes of CO ₂ gas flowing at 75 ° C for 120 minutes were analyzed and compared.

In order to desorb the CO ₂ of the sample as much as possible, the sample was stabilized by purging with nitrogen for 180 minutes at a temperature of 75 ° C where CO ₂ adsorption / desorption is most likely to occur. The maximum value (mg or mmol) of CO ₂ adsorbed per 1 g of each adsorbent when exposed to CO ₂ for 180 minutes after nitrogen purge is summarized in Table 3, and the graph of CO ₂ adsorption over time of each adsorbent is shown in FIG. .

As a result of the analysis, it can be seen that the adsorption rate is fast enough to cause more than 90% CO ₂ adsorption within the initial 30 minutes. The most adsorbed carbon dioxide in the produced samples is 70K-M25 The adsorption amount was measured to be 2.94 mmol. The higher the molecular weight, the more CO ₂ adsorption occurred. This is because the higher the molecular weight, the higher the secondary amine content.

Name of sample Absorption CO2 maximum value
(mg CO ₂ / g adsorbent) Absorption CO2 maximum value
(mmol CO ₂ / g adsorbent) (a) 2K-M25 32.90 0.75 (b) 2K-M37.5 46.09 1.05 (c) 2K-M50 78.02 1.77 (d) 25K-M25 72.31 1.64 (e) 25K-M37.5 90.02 2.05 (f) 25K-M50 95.80 2.18 (g) 70K-M25 129.19 2.94 (h) 70K-M37.5 128.22 2.92 (k) 70K-M50 84.25 1.91

The carbon dioxide adsorbent of the present invention was prepared by not using any inorganic particles such as SiO ₂ and inducing a small amount of crosslinking reaction within a range that does not impair the inherent CO ₂ adsorption property of PEI. Since the carbon dioxide adsorbent of the present invention is composed of only 100% organic material, it is relatively light compared to the adsorbent impregnated in the conventional inorganic particles, and thus it has a high CO ₂ adsorption performance because it contains much larger amounts of amine functional groups at the same unit weight However, the amount of adsorption was similar to that of the adsorbed material impregnated in the porous material. From this, it can be seen that the portion of the PEI particles of the present invention capable of adsorbing carbon dioxide does not exist outside the surface. In the case of impregnated adsorbents, the adsorption capacity of carbon dioxide was lowered due to the reduction of specific surface area in the case of over 50% impregnation. Therefore, if the specific surface area of the PEI particles can be controlled, the CO ₂ adsorption ability is expected to be further improved compared to the same unit weight.

Claims (9)

A first step of preparing a water-in oil (W / O) type polyethyleneimine emulsion by adding a polyethyleneimine (PEI) solution as a water-soluble dispersed phase to a continuous phase prepared by mixing an organic solvent and an emulsifier;
A second step of adding glutaraldehyde to the polyethyleneimine emulsion to prepare a polyethyleneimine particle crosslinked with glutaraldehyde by proceeding a cross-linking reaction between the amino group of the polyethyleneimine contained in the emulsion and the aldehyde group of glutaraldehyde; And
And a third step of drying the crosslinked polyethyleneimine particles of the glutaraldehyde,
Wherein the polyethyleneimine has a weight average molecular weight of more than 25,000 but not more than 70,000 and a reaction molar ratio of polyethyleneimine and glutaraldehyde is 1: 0.25 to 0.375 so as to increase the amount of carbon dioxide adsorption, and carbon dioxide gas containing glutaraldehyde crosslinked polyethyleneimine particles A method for producing an adsorbent. The process according to claim 1, wherein the amount of the emulsifier used is 2 to 10% by weight of the total weight of the continuous phase. delete The production method according to claim 1, wherein the content of polyethyleneimine in the polyethyleneimine solution is 15 to 25% by weight. delete A carbon dioxide adsorbent comprising glutaraldehyde crosslinked polyethyleneimine particles prepared according to any one of claims 1, 2, and 4. 7. The carbon dioxide adsorbent according to claim 6, wherein the final decomposition temperature of the polyethyleneimine particles is 450 DEG C or higher. The carbon dioxide adsorbent according to claim 6, wherein the diameter of the polyethyleneimine particles is 200 nm to 15 占 퐉. delete

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