KR102354125B1 - Crystalline sillica-based entrapping agent for treating carbon dioxide containing radioactive carbon and method for preparing the same and system for treating carbon dioxide containing radioactive carbon using the same - Google Patents

Abstract

The present invention relates to a silica structure; and a crystalline structure comprising boron oxide ions and alkaline earth metal ions impregnated in the silica structure, wherein oxygen ions in the alkaline earth metal ion and the boron oxide ion form an ionic bond. Silica-based trapping agent; its manufacturing method; And it relates to a radiocarbon-containing carbon dioxide treatment system using the same.

Description

CRYSTALLINE SILLICA-BASED ENTRAPPING AGENT FOR TREATING CARBON DIOXIDE CONTAINING RADIOACTIVE CARBON AND METHOD FOR PREPARING THE SAME AND SYSTEM FOR TREATING CARBON DIOXIDE CONTAINING RADIOACTIVE CARBON USING THE SAME}

The present invention relates to a crystalline silica-based trapping agent for treating carbon dioxide containing radioactive carbon, a method for preparing the same, and a system for treating carbon dioxide containing radioactive carbon using the same.

Among various wastes generated from nuclear power facilities, the problem of treatment of carbon waste containing radioactive carbon (C-14) is seriously emerging. Not only is the amount of radiocarbon-containing carbon waste stored and stored in nuclear facilities significant, but at this time, the half-life of radiocarbon is also incredibly long, about 5730±40 years. Moreover, unlike other radionuclides, since radiocarbon can be substituted with organic matter, it has the potential to be very harmful to living things, so it must be treated in a stable form.

When carbon waste containing radiocarbon (C-14) is thermochemically treated, carbon dioxide containing radioactive carbon is generated, and a technology is required to capture it and make it into a form suitable for subsequent treatment. Accordingly, various methods have been developed to effectively capture radiocarbon-containing carbon dioxide. In order to make it suitable for subsequent treatment, it should be captured in the form of carbonate. However, since extreme conditions are mainly required to form the carbonate, it is not suitable for the stability of radioactive waste when dealing with carbon dioxide containing radioactive carbon. Therefore, there is a need for a technology for capturing radiocarbon-containing carbon dioxide with high efficiency (fast reaction rate and high capture amount) under mild reaction conditions.

Korean Patent Publication No. 10-1545440 (2015. 08. 11.)

The present invention is for capturing radioactive carbon-containing carbon dioxide with high efficiency (fast reaction rate and high capture amount) under mild reaction conditions, comprising: a silica structure; and a crystalline structure comprising boron oxide ions and alkaline earth metal ions impregnated in the silica structure, wherein oxygen ions in the alkaline earth metal ion and the boron oxide ion form an ionic bond. An object of the present invention is to provide a silica-based collector and the like.

However, the technical problem to be achieved by the present invention is not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

The present invention relates to a silica structure; and a crystalline structure comprising boron oxide ions and alkaline earth metal ions impregnated in the silica structure, wherein oxygen ions in the alkaline earth metal ion and the boron oxide ion form an ionic bond. A silica-based collector is provided.

In an embodiment of the present invention, (a) mixing silica, boron oxide and alkaline earth metal oxide, melting and cooling to prepare an amorphous silica-based trapping agent; and (b) raising the temperature of the prepared amorphous silica-based trapping agent to a crystalline temperature or higher, maintaining it for a certain period of time, and then cooling it. provide a way

In another embodiment of the present invention, a carbon dioxide gas cylinder for supplying carbon dioxide containing radioactive carbon; a carbon dioxide capture reactor for converting the supplied carbon dioxide into liquefaction and carbonate; and a carbon dioxide detector for detecting the generation of the uncaptured carbon dioxide, wherein the carbon dioxide capture reactor includes the crystalline silica-based collector dispersed in water, and provides a carbon dioxide treatment system containing radioactive carbon.

The crystalline silica-based scavenger for the treatment of carbon dioxide containing radioactive carbon according to the present invention has a silica structure; and a crystalline structure comprising boron oxide ions and alkaline earth metal ions impregnated in the silica structure, wherein oxygen ions in the alkaline earth metal ions and the boron oxide ions form an ionic bond, such crystals Sexual structures can be formed through molecular rearrangement by controlled heat treatment.

When the crystalline silica-based trapping agent for treating carbon dioxide containing radioactive carbon according to the present invention is used in a dispersed state in water, ionic bonds can be easily dissociated, so that under mild reaction conditions, high efficiency (fast reaction rate and high collection amount) Carbon dioxide containing radioactive carbon can be captured. In particular, since carbon dioxide containing radioactive carbon can be captured in the form of carbonate suitable for immobilization and solidification, it is expected to create great demand for the capture of radiocarbon in carbon waste.

1 is a photograph comparing SEM images before (a) and after (b) carbon dioxide capture of the crystalline silica-based trapping agent according to Example 1.
Figure 2 (a) is a graph comparing the XRD patterns before and after carbon dioxide capture of the crystalline silica-based trapping agent according to Example 1, Figure 2 (b) is the carbon dioxide of the crystalline silica-based trapping agent according to Example 1 It is a graph comparing the TGA curves before and after collection.
3 is a graph showing the carbon dioxide capture amount calculated from the crystalline silica-based collector according to Example 1 according to the carbon dioxide capture time.
Figure 4 (a) is a graph comparing the XRD patterns before and after carbon dioxide capture of the crystalline silica-based trapping agent according to Example 2, Figure 4 (b) is the carbon dioxide of the crystalline silica-based trapping agent according to Example 2 It is a graph comparing the TGA curves before and after collection.
5 is a graph showing the carbon dioxide capture amount calculated from the crystalline silica-based collector according to Example 2 according to the carbon dioxide capture time.

According to the conventional method, there have been examples of using calcium oxide or the like as a method for capturing radiocarbon-containing carbon dioxide in the form of carbonate, but in the case of calcium oxide, calcium and oxygen are connected by a covalent bond, so it is a very stable mineral by itself. are treated Therefore, when this is used, there is a limit that the mineralization (carbonation) reaction for capturing the radiocarbon-containing carbon dioxide in the form of carbonate hardly occurs or, even if it occurs, the rate is very slow under mild conditions such as room temperature and atmospheric pressure. On the other hand, there is a problem in that a large amount of energy is required to set the high temperature and high pressure conditions, and the handling of radioactive materials is dangerous due to instability to extreme conditions.

Accordingly, the present inventors prepared a crystalline silica-based trapping agent for treating carbon dioxide containing radioactive carbon, in which alkaline earth metal ions include a crystalline structure that forms an ionic bond with oxygen ions in boron oxide ions, instead of the conventional method, When used in a dispersed state, it is possible to easily dissociate ionic bonds, so it is confirmed that radioactive carbon-containing carbon dioxide can be captured with high efficiency (fast reaction rate and high capture amount) even under mild conditions such as room temperature and atmospheric pressure, and the present invention completed.

As used herein, "radioactive carbon" is a type of isotope of carbon, and generally refers to C-14. At this time, the half-life of radiocarbon is also incredibly long, about 5730±40 years. Moreover, radiocarbon, unlike other radionuclides, can be substituted with organic matter, so it has the potential to be very harmful to living things.

Hereinafter, the present invention will be described in detail.

Crystalline silica-based trapping agent for carbon dioxide treatment containing radioactive carbon

The present invention relates to a silica structure; and a crystalline structure comprising boron oxide ions and alkaline earth metal ions impregnated in the silica structure, wherein oxygen ions in the alkaline earth metal ion and the boron oxide ion form an ionic bond. A silica-based collector is provided.

Optionally, as an additive for forming a glass material in the silica structure, sodium oxide, calcium oxide or ions thereof may be further impregnated.

The crystalline silica-based trapping agent according to the present invention refers to a glass material having a crystalline structure for trapping radioactive carbon-containing carbon dioxide in the form of carbonate.

Specifically, the crystalline silica-based scavenger according to the present invention has a silica structure; and a crystalline structure comprising boron oxide ions and alkaline earth metal ions impregnated in the silica structure, wherein the alkaline earth metal ions and oxygen ions in the boron oxide ions form an ionic bond, wherein the crystalline structure is controlled It can be formed through molecular rearrangement by heat treatment. Molecular rearrangement by controlled heat treatment will be described later.

The silica structure constitutes a skeleton of a glass material, in which oxygen is shared by two silicons, and may have a network structure.

The boron oxide ion refers to a state in which one or more oxygen bonds are broken in boron oxide to give an anion, and may be _{BO 2} ^-. In addition, the alkaline earth metal ion refers to a state in which all oxygen bonds in the alkaline earth metal oxide are broken so that the alkaline earth metal has a cation, and ^{may be expressed as M 2+} (in this case, M is an alkaline earth metal).

The alkaline earth metal ion has a crystalline structure by forming an ionic bond with an oxygen ion in the boron oxide ion. , it is possible to capture radiocarbon-containing carbon dioxide with high efficiency (fast reaction rate and high capture amount).

More specifically, the crystalline structure may include a structure represented by the following Chemical Formula 1:

[Formula 1]

In the above formula, M is an alkaline earth metal, and the alkaline earth metal ion is at least one selected from the group consisting of strontium (Sr), calcium (Ca), barium (Ba), radium (Ra), magnesium (Mg), and beryllium (Be). It may contain ions, and in consideration of the radius size, it is preferable to include strontium (Sr) or calcium (Ca), and it is most preferable to include strontium (Sr) in terms of efficiency, but is not limited thereto.

Meanwhile, the crystalline silica-based collector may be in a gel state dispersed in water. When the crystalline silica-based trapping agent is dispersed in water, the surface of the crystalline silica-based trapping agent may be converted from a glass state to a gel state. Therefore, after the radiocarbon-containing carbon dioxide is captured, it has the advantage of easy separation.

Method for manufacturing crystalline silica-based trapping agent for carbon dioxide treatment containing radioactive carbon

The present invention comprises the steps of (a) mixing silica, boron oxide and alkaline earth metal oxide, melting, and cooling to prepare an amorphous silica-based trapping agent; and (b) raising the temperature of the prepared amorphous silica-based trapping agent to a crystalline temperature or higher, maintaining it for a certain period of time, and then cooling it. provide a way

First, the method for producing a crystalline silica-based trapping agent according to the present invention comprises the steps of mixing silica, boron oxide and alkaline earth metal oxide, melting, and cooling to prepare an amorphous silica-based trapping agent [step (a)] includes

The molar ratio of the silica, boron oxide and alkaline earth metal oxide is preferably 30: 15: 55 to 40: 25: 35, but is not limited thereto. In this case, the silica serves to constitute a skeleton of the glass material of the silica-based collector. The boron oxide also serves as an additive to form a backbone and form a glass material to lower the viscosity and melting point. In addition, the alkaline earth metal oxide serves to react with carbon dioxide containing radioactive carbon. The melting may be performed at 900° C. to 1400° C. for 0.5 hours to 1.5 hours, and an amorphous silica-based trapping agent can be prepared under these melting conditions. Then, the cooling is characterized in that it is made quickly, the rate may be 100 ℃ / min to 200 ℃ / min. Due to this quenching, rearrangement of the molecules would be impossible.

In addition, sodium oxide, potassium oxide, or a mixture thereof may be mixed as a mesh modified oxide, and the amount thereof may be 1 mol% to 10 mol% based on the silica, boron oxide and alkaline earth metal oxide.

Next, the method for producing a crystalline silica-based trapping agent according to the present invention comprises the steps of raising the temperature of the prepared amorphous silica-based trapping agent above the crystalline temperature, maintaining it for a certain period of time, and then cooling [(b) step ] is included.

By performing a controlled heat treatment on the prepared amorphous silica-based trapping agent to rearrange the molecules, a crystalline structure can be formed. decide to do Therefore, when the crystalline silica-based trapping agent is dispersed in water, it is possible to dissociate ionic bonds and collect radiocarbon-containing carbon dioxide with high efficiency (fast reaction rate and high collection amount) under mild reaction conditions. On the other hand, when the amorphous silica-based trapping agent is dispersed in water, there is a limit in that the trapping efficiency of radiocarbon-containing carbon dioxide is relatively reduced due to the absence of ionic bonds.

The temperature increase is for freeing the movement of molecules for molecular rearrangement, and is preferably performed at a rate of 1°C/min to 10°C/min, but is not limited thereto.

The temperature rise is made above the crystalline temperature, the crystalline temperature is to be 700 ℃ to 800 ℃, it is necessary to raise the temperature to a temperature higher than that. In this case, when strontium (Sr) oxide is used as the alkaline earth metal oxide, the crystallinity temperature is about 800° C., and when calcium (Ca) oxide is used as the alkaline earth metal oxide, the crystallinity temperature is about 780° C.

Maintaining for a certain period of time above the crystalline temperature is to free the movement of molecules by processing at a high temperature to have a crystalline structure and, while cooling slowly, to rearrange the molecules, and to be maintained for 30 minutes to 10 hours. and preferably maintained for 1 hour to 3 hours, but is not limited thereto. At this time, a crystal that breaks one or more oxygen bonds in the boron oxide to form boron oxide ions with an anion, breaks all oxygen bonds in the alkaline earth metal oxide to form alkaline earth metal ions with positive ions, and forms ionic bonds between them It may contain gender structures. Then, the cooling is characterized in that it is made gradually, the rate may be 5 ℃ / min to 10 ℃ / min. Due to this slow cooling, the molecules may rearrange.

Radiocarbon-containing carbon dioxide treatment system and method

The present invention is a carbon dioxide gas cylinder for supplying carbon dioxide containing radioactive carbon; a carbon dioxide capture reactor for converting the supplied carbon dioxide into liquefaction and carbonate; and a carbon dioxide detector for detecting the generation of the uncaptured carbon dioxide, wherein the carbon dioxide capture reactor includes the crystalline silica-based collector dispersed in water, and provides a carbon dioxide treatment system containing radioactive carbon.

In addition, there is provided a method for treating carbon dioxide containing radioactive carbon using the system.

First, the system for treating carbon dioxide containing radioactive carbon according to the present invention includes a carbon dioxide gas cylinder; carbon dioxide capture reactor; and a carbon dioxide detector, and optionally, a centrifuge, and each device may be connected via tubing.

Specifically, the system for treating carbon dioxide containing radioactive carbon according to the present invention includes a carbon dioxide gas cylinder, wherein the carbon dioxide gas cylinder serves to supply carbon dioxide containing radioactive carbon. A main valve, a regulator, and a needle valve may be further included sequentially at the rear end of the carbon dioxide gas cylinder.

To this end, the carbon dioxide gas cylinder may be charged with a carbon waste gas containing radioactive carbon and optionally a catalyst, which may be carried out under oxygen or air. In addition, the carbon dioxide gas cylinder needs to maintain temperature and pressure conditions for generating radiocarbon-containing carbon dioxide from radiocarbon-containing carbon waste gas, and a temperature of 40° C. to 200° C. and a pressure of ^{10 -1} Pa to 10 ^{5 Pa.} It is preferable to maintain the conditions, but is not limited thereto.

In addition, the radiocarbon-containing carbon dioxide treatment system according to the present invention includes a carbon dioxide capture reactor, wherein the carbon dioxide capture reactor serves to convert the supplied carbon dioxide into liquefaction and carbonate. A plurality of the carbon dioxide capture reactor may be connected in series.

The rate of carbon dioxide supplied to the carbon dioxide capture reactor may be 0.5 ml/min to 5.0 ml/min, preferably 0.5 ml/min to 2.0 ml/min, but is not limited thereto. At this time, when the speed of carbon dioxide supplied to the carbon dioxide capture reactor is faster than the above range, there is a problem in that excessive generation of uncollected carbon dioxide occurs.

In particular, the carbon dioxide trapping reactor includes the crystalline silica-based trapping agent dispersed in water, and the carbon dioxide trapping reactor may include a stirring device for dispersing water and the crystalline silica-based trapping agent. At this time, since the "crystalline silica-based collector", in particular, the "crystalline silica collector dispersed in water" has been described above, a redundant description will be omitted.

The carbon dioxide trapping reactor may contain 1 g to 10 g of the crystalline silica-based trapping agent with respect to 100 ml of the water, and it is preferable to include 2 g to 6 g of the crystalline silica-based trapping agent, not limited This is the content set to minimize the generation of excess carbon dioxide that is not captured.

Dispersion of the crystalline silica-based trapping agent in the carbon dioxide trapping reactor may be performed at 100 rpm to 1,000 rpm conditions, and is preferably performed at 300 rpm to 1,000 rpm conditions, but is not limited thereto. Accordingly, the crystalline silica-based collector can be well dispersed in water.

Since the alkaline earth metal ions in the crystalline silica-based trapping agent have an advantage that they can easily react with carbon dioxide containing radioactive carbon, the carbon dioxide trapping reactor has sufficient advantages even when maintaining mild conditions such as room temperature and atmospheric pressure. Accordingly, the carbon dioxide capture reactor is preferably maintained at a temperature of 20°C to 40°C and a pressure condition of 0.5 atm to 1.5 atm, but is not limited thereto. In addition, the carbon dioxide capture reaction may be performed within 5 hours, preferably for 1 hour to 3 hours.

Optionally, it may further include a centrifuge for separating the carbonate (or the crystalline silica-based trapping agent in which the carbonate is collected) converted in the carbon dioxide capture reactor.

In addition, the radiocarbon-containing carbon dioxide treatment system according to the present invention includes a carbon dioxide detector, wherein the carbon dioxide detector serves to detect the generation of the excess carbon dioxide that is not captured. This can be checked continuously and in real time.

As described above, the crystalline silica-based scavenger for treating radioactive carbon-containing carbon dioxide according to the present invention has a silica structure; and boron oxide ions and alkaline earth metal ions impregnated in the silica structure, wherein the alkaline earth metal ions include a crystalline structure that forms an ionic bond with oxygen ions in the boron oxide ions, such crystals Sexual structures can be formed through molecular rearrangement by controlled heat treatment.

When the crystalline silica-based trapping agent for treating carbon dioxide containing radioactive carbon according to the present invention is used in a dispersed state in water, ionic bonds can be easily dissociated, so that under mild reaction conditions, high efficiency (fast reaction rate and high collection amount) Carbon dioxide containing radioactive carbon can be captured. In particular, since carbon dioxide containing radioactive carbon can be captured in the form of carbonate suitable for immobilization and solidification, it is expected to create great demand for the capture of radiocarbon in carbon waste.

Hereinafter, preferred examples are presented to help the understanding of the present invention. However, the following examples are only provided for easier understanding of the present invention, and the contents of the present invention are not limited by the following examples.

[Example]

Example 1

(1) SiO ₂ , B ₂ O ₃ , Na ₂ O and SrO were mixed in a molar ratio of 35: 20: 5: 40 in a platinum crucible, and melted at about 1350° C. for about 1 hour. Then, the platinum crucible was taken out, and the melt was poured on a graphite plate at about 25° C. and cooled rapidly to prepare an amorphous silica-based trapping agent. Thereafter, the temperature was raised to about 800°C at a rate of about 5°C/min, maintained at that temperature for about 1 hour, and then slowly cooled to about 25°C by turning off the electric furnace to prepare a crystalline silica-based collector. . Thereafter, after grinding with a planetary mill (SPEX SamplePrep 8000M), it was recovered to a constant size of <45 μm through an auto sieve (Orto Alresa OASS 203). At this time, the XRD pattern, TGA curve, and SEM image of the crystalline silica-based collector are confirmed through FIGS. 1(a) and (b) and FIG. 2(a).

Then, 50 ml of ultrapure water and 2 g of a crystalline silica-based trapping agent were added to the carbon dioxide trapping reactor, and then the reactor lid was closed. Thereafter, the crystalline silica-based trapping agent was well dispersed in ultrapure water by stirring at a high speed of about 500 rpm using a stirring device provided in the carbon dioxide trapping reactor.

(2) As a simulation experiment, carbon dioxide was generated by injecting carbon dioxide into a carbon dioxide gas cylinder as a simulation, instead of generating radioactive carbon-containing carbon dioxide by putting a radioactive carbon-containing carbon waste gas and a platinum catalyst into a carbon dioxide gas cylinder under oxygen or air. By opening the main valve located at the rear end of the carbon dioxide gas cylinder, the generated carbon dioxide was moved along the plastic tubing at a rate of 1 ml/min to the regulator. Thereafter, a needle valve located at the rear end of the regulator was opened, and the moved carbon dioxide was supplied to the carbon dioxide capture reactor along the plastic tubing.

(3) The supplied carbon dioxide was liquefied for about 3 hours in a carbon dioxide capture reactor maintaining a temperature of about 25° C. and a pressure of about 1 atm, and then a reaction was carried out to convert it into carbonate, and the reaction was carried out through droplets generated in the aqueous solution. Check whether this is going on or not.

(4) The generation of uncaptured carbon dioxide was checked continuously and in real time through a carbon dioxide detector.

(5) After the carbon dioxide capture reaction was completed, the crystalline silica-based trapping agent and aqueous solution in which carbonate was collected were separated and recovered through a centrifugal separator, and the aqueous solution was diluted and used for concentration measurement, and the crystalline silica-based agent in which carbonate was collected The collector was completely dried and then used for quantitative and qualitative analysis. At this time, the SEM image, XRD pattern, and TGA curve of the crystalline silica-based trapping agent in which the carbonate is collected are confirmed through FIGS. 1 and 2 . In addition, the amount of carbon dioxide capture calculated from the crystalline silica-based collector in which the carbonate is captured is confirmed through FIG. 3 .

Comparative Example 1

(1) SiO ₂ , B ₂ O ₃ , Na ₂ O and SrO were mixed in a molar ratio of 35: 20: 5: 40 in a platinum crucible, and melted at about 1350° C. for about 1 hour. Then, the platinum crucible was taken out, and the melt was poured on a graphite plate at about 25° C. and cooled rapidly to prepare an amorphous silica-based trapping agent. Thereafter, while omitting the controlled heat treatment, it was pulverized with a planetary mill (SPEX SamplePrep 8000M), and then recovered to a constant size of <45 μm through an auto sieve (Orto Alresa OASS 203). At this time, the XRD pattern and TGA curve of the amorphous silica-based collector are confirmed through FIG. 2 .

Then, 50 ml of ultrapure water and 2 g of an amorphous silica-based trapping agent were added to the carbon dioxide trapping reactor, and then the reactor lid was closed. Thereafter, the amorphous silica-based trapping agent was well dispersed in ultrapure water by stirring at a high speed of about 500 rpm using a stirring device provided in the carbon dioxide trapping reactor.

Then, carbon dioxide was treated in the same manner as in Example 1 (2) to (5).

Example 2

(1) An amorphous silica-based trapping agent was prepared in the same manner as in Example 1, except that CaO was used instead of SrO. Then, the temperature was raised to about 950°C at a rate of about 10°C/min, maintained at that temperature for about 2 hours, and then slowly cooled to about 25°C by turning off the electric furnace to prepare a crystalline silica-based trapping agent did. Thereafter, after grinding with a planetary mill (SPEX SamplePrep 8000M), it was recovered to a constant size of <45 μm through an auto sieve (Orto Alresa OASS 203). At this time, the XRD pattern and TGA curve of the crystalline silica-based collector are confirmed through FIG. 4 .

Then, 50 ml of ultrapure water and 2 g of a crystalline silica-based trapping agent were added to the carbon dioxide trapping reactor, and then the reactor lid was closed. Thereafter, the crystalline silica-based trapping agent was well dispersed in ultrapure water by stirring at a high speed of about 500 rpm using a stirring device provided in the carbon dioxide trapping reactor.

Then, carbon dioxide was treated in the same manner as in Example 1 (2) to (5).

Comparative Example 2

(1) An amorphous silica-based trapping agent was prepared in the same manner as in Example 1, except that CaO was used instead of SrO. Thereafter, while omitting the controlled heat treatment, it was pulverized with a planetary mill (SPEX SamplePrep 8000M), and then recovered to a constant size of <45 μm through an auto sieve (Orto Alresa OASS 203). At this time, the XRD pattern of the amorphous silica-based collector is confirmed through FIG.

Then, 50 ml of ultrapure water and 2 g of an amorphous silica-based trapping agent were added to the carbon dioxide trapping reactor, and then the reactor lid was closed. Thereafter, the amorphous silica-based trapping agent was well dispersed in ultrapure water by stirring at a high speed of about 500 rpm using a stirring device provided in the carbon dioxide trapping reactor.

Then, carbon dioxide was treated in the same manner as in Example 1 (2) to (5).

As shown in FIG. 1(a), the average particle size of the crystalline silica-based trapping agent according to Example 1 was found to be at a fine level of about 100 μm or less (about 75 μm) before carbon dioxide capture, but minerals after carbon dioxide capture It is confirmed that the carbonization (carbonation) reaction proceeds, and a large _{number of SrCO 3 having an even size is generated.}

As shown in FIG. 2( a ), as a result of XRD pattern analysis, it was confirmed that the amorphous silica-based trapping agent according to Comparative Example 1 did not have a crystalline structure, but the crystalline silica-based trapping agent according to Example 1 In the case of , it is confirmed to have a crystalline structure (Strontium metaborate; SrB ₂ O _{4 ) through molecular rearrangement.} In addition, in the case of the crystalline silica-based scavenger according to Example 1, a new XRD peak is confirmed after capturing carbon dioxide, which can be considered due to the generation of _{SrCO 3 .}

As shown in FIG. 2(b) , as a result of the TGA curve analysis, in the case of the crystalline silica-based trapping agent according to Example 1, a sharp change in the TGA curve was observed at about 600° C. after 1 hour of carbon dioxide capture, which This may be due to thermal decomposition. On the other hand, even when looking at the TGA curve after 12 hours of carbon dioxide capture, there was no significant difference from the TGA curve after 1 hour of carbon dioxide capture. Through this, the conversion of carbon dioxide into liquefaction and carbonate is completed within 1 hour, and it can be seen that the carbon dioxide has a fast reaction rate. On the other hand, in the case of the amorphous silica-based trapping agent according to Comparative Example 1, compared to the crystalline silica-based trapping agent according to Example 1, the degree of change in the TGA curve at about 600°C after 1 hour of carbon dioxide capture was relatively insignificant. is observed to be

From these results, when the crystalline silica-based trapping agent in which the molecules are rearranged by performing a controlled heat treatment on the amorphous silica-based trapping agent is used, carbon dioxide can be effectively converted into a carbonate form compared to the case of using the amorphous silica-based trapping agent. It can be viewed as being collectible.

_{As shown in Figure 3, the carbon dioxide capture amount (CO 2} capacity) from the crystalline silica-based collector according to Example 1 according to the carbon dioxide capture time was calculated through the following formula:

CO ₂ capacity (mmol CO ₂ /g adsorbent) =

이고, A는 이산화탄소가 분해되기 시작하는 600 ℃의 온도에서 TGA로부터 획득된 중량 %이고, B는 TGA 곡선이 안정된 경우에 중량 %이다. where X is

, A is the weight % obtained from TGA at a temperature of 600° C. at which carbon dioxide starts to decompose, and B is the weight % when the TGA curve is stable.

As a result, it is confirmed that carbon dioxide can be captured with high efficiency (fast reaction rate (≥4.54 mmol/gh) and high capture amount (4.54 mmol/g)). This is a value corresponding to 90% of the theoretical value (5.0 mmol/g) assuming that all of Sr reacted with carbon dioxide, which is significantly higher than that of the amorphous silica-based trapping agent according to Comparative Example 1, which is 4.2 mmol/g. is the value

As shown in FIG. 4( a ), as a result of XRD pattern analysis, it was confirmed that the amorphous silica-based trapping agent according to Comparative Example 2 did not have a crystalline structure, but the crystalline silica-based trapping agent according to Example 2 In the case of , it is confirmed to have a crystalline structure (calcium metaborate; CaB ₂ O _{4 ) through molecular rearrangement.} In addition, in the case of the crystalline silica-based scavenger according to Example 1, a new XRD peak is confirmed after capturing carbon dioxide, which can be considered due to the generation of _{CaCO 3 .}

As shown in FIG. 4(b), as a result of the TGA curve analysis, in the case of the crystalline silica-based trapping agent according to Example 2, a change in the TGA curve was observed at about 600° C. 1 hour after carbon dioxide capture, which is the thermal decomposition of carbonate may be considered due to

As shown in FIG. 5 , as a result of calculating the amount of the crystalline silica-based trapping agent according to Example 2 according to the carbon dioxide trapping time, relatively high efficiency (relatively fast reaction rate (≥3.82 mmol/gh) and relatively high It is confirmed that carbon dioxide can be captured with a capture amount (3.40 mmol/g)). This is a value corresponding to 51% of the theoretical value (6.6 mmol/g) assuming that all of Ca reacted with carbon dioxide.

The above description of the present invention is for illustration, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (13)

silica structure; and
Including boron oxide ions and alkaline earth metal ions impregnated in the silica structure,
and a crystalline structure in which oxygen ions in the alkaline earth metal ions and the boron oxide ions form an ionic bond,
The crystalline structure is a crystalline silica-based trapping agent for treating carbon dioxide containing radioactive carbon comprising a structure represented by the following formula (1).
[Formula 1]

In the above formula, M is an alkaline earth metal.
delete The method of claim 1,
The alkaline earth metal ion includes at least one ion selected from the group consisting of strontium (Sr), calcium (Ca), barium (Ba), radium (Ra), magnesium (Mg) and beryllium (Be), crystalline silica-based collector.
The method of claim 1,
The crystalline silica-based trapping agent is in a gel state dispersed in water, the crystalline silica-based trapping agent.
(a) mixing silica, boron oxide and alkaline earth metal oxide, melting and cooling to prepare an amorphous silica-based scavenger; and
(b) raising the temperature of the prepared amorphous silica-based trapping agent to a crystalline temperature or higher, maintaining it for a certain period of time, and then cooling to prepare a crystalline silica-based trapping agent; including,
The crystalline silica-based trapping agent is a method for producing a crystalline silica-based trapping agent comprising a structure represented by the following formula (1).
[Formula 1]

In the above formula, M is an alkaline earth metal.
6. The method of claim 5,
The molar ratio of silica, boron oxide and alkaline earth metal oxide in step (a) is 30: 15: 55 to 40: 25: 35, the method for producing a crystalline silica-based trapping agent.
6. The method of claim 5,
The melting in step (a) is carried out at 900 ℃ to 1400 ℃, a method for producing a crystalline silica-based trapping agent.
6. The method of claim 5,
The crystallinity temperature in step (b) is 700 ℃ to 800 ℃, the method for producing a crystalline silica-based trapping agent.
6. The method of claim 5,
The method of producing a crystalline silica-based trapping agent, wherein the temperature increase in step (b) is performed at a rate of 1 °C / min to 10 °C / min.
6. The method of claim 5,
The maintenance in step (b) is for 30 minutes to 10 hours, the method for producing a crystalline silica-based trapping agent.
a carbon dioxide gas cylinder for supplying carbon dioxide containing radioactive carbon;
a carbon dioxide capture reactor for converting the supplied carbon dioxide into liquefaction and carbonate; and
A carbon dioxide detector for detecting the generation of the uncaptured carbon dioxide,
The carbon dioxide capture reactor comprises a crystalline silica-based collector according to any one of claims 1, 3 and 4 dispersed in water, a carbon dioxide treatment system containing radioactive carbon.
12. The method of claim 11,
The carbon dioxide capture reactor contains, with respect to 100 ml of the water, 1 g to 10 g of the silica-based trapping agent, a carbon dioxide treatment system containing radioactive carbon.
12. The method of claim 11,
The carbon dioxide capture reactor maintains a temperature of 20° C. to 40° C. and a pressure condition of 0.5 atm to 1.5 atm, a carbon dioxide treatment system containing radioactive carbon.

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