KR101306122B1 - A method for sequestration of carbon dioxide by synthesis of magnesite from serpentine - Google Patents

Abstract

The present invention relates to a method for producing cubic magnesium carbonate, namely magnesite by reacting carbon dioxide and serpentine. More specifically, it is pulverized to 43 ~ 74 ㎛ and heat-treated in the range of 600 ~ 800 ℃, mixed in an alkaline solution to prepare a slurry of pH 10 ~ 14 range. The slurry is placed in a high temperature and high pressure reactor, and carbon dioxide is carbonized at a pressure of 1 to 5 MPa at a range of 100 to 250 ° C. to prepare serpentine in the form of cubic magnesium carbonate, that is, magnesite. It is about.
Therefore, the manufacturing method can stably fix or store the carbon dioxide, there is an advantage that can solve the environmental problems caused by greenhouse gases.

Description

A method for sequestration of carbon dioxide by synthesis of magnesite from serpentine}

The present invention relates to a method for producing cubic magnesium carbonate using serpentine and a method for immobilizing carbon dioxide through the method. More specifically, the present invention relates to a method for producing a cubic magnesium carbonate that can fix carbon dioxide by directly performing a carbonation reaction in a single step of manufacturing a cubic magnesium carbonate using serpentine.

Fossil fuels are an important energy source used around the world, accounting for about 80-85% of the total energy sources because of their high energy efficiency, simplicity of storage, established infrastructure and low cost. However, the indiscriminate use of fossil fuels has resulted in the release of large amounts of greenhouse gases, resulting in environmental pollution such as global warming and disturbance of ecosystems. In particular, carbon dioxide is emitted the most among greenhouse gases, and stable carbon dioxide storage technology is required to reduce carbon dioxide.

Mineral carbonation is a technology that converts minerals into CO2 minerals that are thermodynamically stable by reaction with CO _2. Wollastonite (CaSiO ₃ ) and olivine containing alkaline earth metals such as calcium (Ca) and magnesium (Mg) Ca / Mg-silicate minerals, such as Mg ₂ SiO ₄ ), have been mainly used. In addition, such silicate minerals have been recognized as suitable starting materials because they are rich in nature and inexpensive. Serpentine is especially abundant in nature and contains about 40% Mg, which is the most useful mineral for mineral carbonation. Serpentine mines also exist in Korea, and some simple uses such as the agricultural use of powder are known so far and are not yet widely known for industrial use. . In particular, if used as a material for the carbonate mineralization of carbon dioxide, the value will be higher along with environmental problems.

Accordingly, Korean Patent Publication No. 2006-0110119 'Heat treatment method for serpentine for carbonate mineralization raw material' improves reactivity with carbon dioxide than untreated serpentine by pulverizing and heat-treating serpentine to remove -OH group and improving crystallinity of serpentine. The Korean Patent Publication No. 2009-0083541, 'Pretreatment Method of Serpentine for Permanent Immobilization of Carbon Dioxide,' also removes the -OH group from the serpentine to improve the reactivity with carbon dioxide, thereby producing carbonates more effectively. The method is presented. However, the above two conventional inventions only provide a pretreatment method for improving the reactivity of serpentine with carbon dioxide, and do not specifically mention a method of fixing carbon dioxide, and also pretreat the serpentine to obtain serpentine in powder form. There is a process problem that requires a reaction to fix carbon dioxide again.

Republic of Korea Patent Publication No. 2006-0110119 (October 24, 2006) Republic of Korea Patent Publication No. 2009-0083541 (August 04, 2009)

 The present invention is to meet the above requirements, the object of the present invention to prepare a cubic magnesium carbonate using a serpentine, and to propose a carbon dioxide immobilization method through the manufacturing method. More specifically, the purpose of the present invention is to propose a method of immobilizing carbon dioxide by direct carbonation of serpentine in a single process.

The present invention is to achieve the above object, and relates to a carbon dioxide immobilization method according to the method for producing a cubic magnesium carbonate using a serpentine. More particularly, the present invention relates to a method for producing cubic magnesium carbonate, which can fix carbon dioxide through a direct carbonation reaction in a single process.

The method for producing the cubic magnesium carbonate is as follows.

a) grinding the serpentine to heat treatment at 600 ~ 800 ℃;

b) preparing a mixture by adding an alkaline solution to the serpentine particles pretreated in step a);

c) injecting carbon dioxide (CO ₂ ) into the prepared mixture at 1 to 5 MPa and performing a carbonation reaction at 100 to 250 ° C. to prepare a slurry containing cubic magnesium carbonate; It relates to a method for producing a cubic magnesium carbonate comprising a.

Also, if necessary, after step c), d) obtaining a cubic magnesium carbonate solid from the prepared slurry; It relates to a cubic magnesium carbonate production method further comprising.

The following describes each configuration step in detail.

The particle size of the serpentine in step a) is not particularly limited, but is preferably in the range of 43 ~ 73㎛. When the serpentine particles are in the above range, the transition to the cubic magnesium carbonate according to the carbonation reaction is smooth and excellent in crystallinity, and thus it is easy to prepare pure cubic magnesium carbonate. That is, when the particle size of the serpentine is in the above range, the reactivity is improved, thereby increasing carbonation efficiency and easily storing and removing carbon dioxide (CO ₂ ).

In addition, if the heat treatment temperature in step a) is less than 600 ℃, it is not possible to remove the water (crystallized water) formed a structural bond in the mineral and the structural water present in the serpentine crystal. When the water exceeds 800 ° C., the structural water and moisture in the serpentine are removed, and lattice deformation and recombination between the serpentine cyclic components are generated by high temperature, so that a multi-phase complex oxide is formed and is stable without being decomposed at the temperature. There is this.

In addition, the heat treatment time in step a) is not significantly limited, but preferably 1 to 4 hours, it is easy to remove the impurities in the serpentine in the range of the time.

In addition, the serpentine particles pre-treated in the step a) is preferably included 1 to 20 parts by weight based on 100 parts by weight of the alkaline solution. More preferably, 1 to 10 parts by weight is easy to recrystallize the cubic magnesium carbonate.

In step b), the alkali solution may be used by dissolving an alkali metal salt in an aqueous solution, and the alkali metal salt may include hydroxides, carbonates, hydrogen carbonates, and the like of alkali metals such as sodium and potassium. Preferably, sodium hydroxide can be used after being dissolved in distilled water. The pH of the alkaline solution is preferably in the range of 10-14. When the pH is in the range, the recrystallization of the cubic magnesium carbonate during the carbonation reaction is easy to improve the recovery rate of magnesium carbonate.

The step c) relates to a carbon dioxide immobilization reaction in which a slurry containing cubic magnesium carbonate is prepared by directly injecting carbon dioxide into the mixture prepared in step b) to perform a direct carbonation reaction. More specifically, step c) relates to the reaction of the carbonate minerals produced by hydrothermal reaction of the metal ions (Mg ^{2 +)} and carbon dioxide gas extracted from the serpentine in the same reactor.

When the carbon dioxide is injected in step c), the pressure is 1 to 5 MPa, and the carbonation reaction temperature is preferably 100 to 250 ° C. When the injection pressure of the carbon dioxide is injected below 1 MPa or more than 5 MPa, it is difficult to crystallize magnesium carbonate due to the lowering of the elution of Mg ^{2 +} ions and the pH decrease during the carbonation reaction, thereby reducing the recovery rate of the cubic magnesium carbonate. There is this.

In addition, when the carbonation reaction proceeds directly below 100 ° C or above 250 ° C, the reaction between serpentine and carbon dioxide is unstable in the same reactor, and the carbonation reaction is inhibited, or other saponite or the like. The formation of phases may cause difficulties in the manufacture of magnesium carbonate, resulting in a reduction in the carbonation rate.

After step c), d) obtaining a cubic magnesium carbonate solid from the prepared slurry; It may further comprise a cubic magnesium carbonate.

Cubic magnesium carbonate prepared by the above production method in the present invention can be confirmed by the X-ray diffraction analysis results of FIG. 2 and electron micrographs of FIG. 3. More specifically, in the X-ray diffraction analysis of FIG. 2, it was confirmed that the bottom intervals were 2.747 kPa (104), 2.108 kPa (113), and 1.705 kPa (116), and thus, cubic magnesium carbonate was prepared. 3 shows that the cubic magnesium carbonate was produced visually.

According to the method for producing cubic magnesium carbonate according to the present invention, it is possible to produce cubic magnesium carbonate which is economical and excellent in crystallinity by directly carbonizing the serpentine particles in a single process.

In addition, by producing a cubic magnesium carbonate with the production method of the present invention can be stably fixed or stored carbon dioxide.

1 is a diagram illustrating a manufacturing process of cubic magnesium carbonate using serpentine according to the present invention.
Figure 2 is a graph showing the results of the cubic magnesium carbonate X-ray diffraction analysis according to the carbon dioxide injection pressure when manufacturing the cubic magnesium carbonate using the serpentine of the present invention.
(a: serpentine b: cubic magnesium carbonate prepared after carbonation at 1.5 MPa, c: cubic magnesium carbonate prepared after carbonation at 3 MPa)
Figure 3 is a scanning electron micrograph of the cubic magnesium carbonate using the serpentine of the present invention.
4 is a graph showing the results of XRD analysis of the cubic magnesium carbonate of Comparative Example 1. (a: x-ray diffraction pattern after heat treatment, b: x-ray diffraction pattern after carbonation reaction)

The present invention will be described in more detail with reference to the following examples. However, the following examples are only to aid the understanding of the present invention, and the scope of the present invention in any sense is not limited by these examples.

Hereinafter, the technical and scientific terms used herein will be understood by those skilled in the art without departing from the scope of the present invention. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

Hereinafter, physical properties were measured by the following method.

1. X-ray diffraction

 X-Ray Diffractometers equipped with graphite (or monochromator) (X'Pert PRO Multi Purpose X-Ray Diffractometer; Cukα radiation (Max. 60 kV, 55 mA)), 2θ range, 1-65.

2. Electron Microscope

Morphology was observed with a scanning electron microscope (FE-SEM, S-4700, Hitachi, Japan).

Example 1

Using a stirring mill (Attrition Mill, KMC-1B, KMC.), A 2mm size zircon ball was charged at 60 vol% in a 1L pot, and stirred for 1 hour at a rotational speed of 1500rpm to grind the serpentine to a size of 63 μm. To prepare serpentine particles. The serpentine particles were heat treated at 630 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 13, and 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 3 MPa, and then reacted for 1 hour with stirring at 150 ° C. to prepare a stable magnesium carbonate slurry. PH after carbonation reaction was 7.2.

The magnesium carbonate slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain 14.6 g of white magnesium carbonate powder.

The prepared magnesium carbonate powder structure was confirmed using an X-ray diffractometer, and is shown in FIG. 2 (C).

[Example 2]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 630 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust pH to 13, and then 10 g of the pulverized serpentine was added to a 1 L reaction vessel.

Injecting carbon dioxide (CO ₂ ) gas into the reaction vessel at a pressure of 1.5 MPa, and reacted for 1 hour while stirring at 150 ℃ to prepare a stable magnesium carbonate slurry.

The magnesium carbonate slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain 13.85 g of white magnesium carbonate powder.

The prepared magnesium carbonate powder structure was confirmed using an X-ray diffractometer, and is shown in FIG. 2 (b).

[Example 3]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 700 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 13, and 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 4 MPa, and reacted for 1 hour with stirring at 250 ° C. to prepare a stable magnesium carbonate slurry.

The magnesium carbonate slurry prepared above was separated from the solid and liquid portions using a centrifugal separator, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white magnesium carbonate powder.

The prepared magnesium carbonate powder structure was confirmed by using an X-ray diffractometer, and it was confirmed that cubic magnesium carbonate was produced by obtaining a graph of the same pattern as in FIG. 2C.

Example 4

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 650 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 10, and then 10 g of the pulverized serpentine particles were added to a 1L reaction vessel.

Injecting carbon dioxide (CO ₂ ) gas into the reaction vessel at a pressure of 1 MPa, and reacted for 1 hour while stirring at 100 ℃ to prepare a stable magnesium carbonate slurry.

The magnesium carbonate slurry prepared above was separated from the solid and liquid portions using a centrifugal separator, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white magnesium carbonate powder.

The prepared magnesium carbonate powder structure was confirmed by using an X-ray diffractometer, and it was confirmed that cubic magnesium carbonate was produced by obtaining a graph of the same pattern as in FIG. 2B.

[Example 5]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 630 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust pH to 13, and then 10 g of the pulverized serpentine particles were added to a 1L reaction vessel.

Injecting carbon dioxide (CO ₂ ) gas into the reaction vessel at a pressure of 3 MPa, and reacted for 1 hour while stirring at 250 ℃ to prepare a stable magnesium carbonate slurry.

The magnesium carbonate slurry prepared above was separated from the solid and liquid portions using a centrifugal separator, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white magnesium carbonate powder.

The prepared magnesium carbonate powder structure was confirmed by using an X-ray diffractometer, and it was confirmed that cubic magnesium carbonate was produced by obtaining a graph of the same pattern as in FIG. 2C.

Comparative Example 1

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 630 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 13, and 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

Carbon dioxide (CO ₂ ) gas was injected into the reaction vessel at a pressure of 0.5 MPa and reacted for 1 hour while stirring at 100 ° C.

The slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain 8.2 g of a reactant.

The prepared powder was confirmed using an X-ray diffractometer, but it was confirmed that no cubic magnesium carbonate was prepared by obtaining a graph of the pattern shown in FIG. 4.

Comparative Example 2

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 630 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust pH to 7, and 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 7 MPa and reacted for 1 hour with stirring at 100 ° C.

The slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white powder.

The prepared white powder was confirmed using an X-ray diffractometer, but it was confirmed that cubic magnesium carbonate was not produced by obtaining a graph of the same pattern as the pattern shown in FIG.

[Comparative Example 3]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 630 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 13, and 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 3 MPa, and reacted for 1 hour while stirring at 80 ° C.

The slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain 8.29 g of a white powder.

The prepared white powder was confirmed using an X-ray diffractometer, but it was confirmed that cubic magnesium carbonate was not produced by obtaining a graph of the same pattern as the pattern shown in FIG.

[Comparative Example 4]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 630 ° C. for 2 hours.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 13, and 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 3 MPa and reacted for 1 hour with stirring at 290 ° C.

The magnesium carbonate slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white reactant.

The prepared white powder was confirmed using an X-ray diffractometer, but it was confirmed that cubic magnesium carbonate was not produced by obtaining a graph of the same pattern as the pattern shown in FIG.

[Comparative Example 5]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 630 ° C. for 1 hour.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 5, and then 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 3 MPa, and reacted for 1 hour with stirring at 100 ° C.

The magnesium carbonate slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white powder.

The prepared white powder was confirmed using an X-ray diffractometer, but it was confirmed that cubic magnesium carbonate was not produced by obtaining a graph of the same pattern as the pattern shown in FIG.

[Comparative Example 6]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 680 ° C. for 1 hour.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust pH to 3, and then 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 3 MPa, and reacted for 1 hour with stirring at 200 ° C.

The slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white powder.

The prepared white powder was confirmed using an X-ray diffractometer, but it was confirmed that cubic magnesium carbonate was not produced by obtaining a graph of the same pattern as the pattern shown in FIG.

[Comparative Example 7]

Serpentine particles were prepared by grinding the serpentine to a size of 63 μm using the same apparatus as in Example 1. The serpentine particles were heat treated at 850 ° C. for 1 hour.

Then, sodium hydroxide (NaOH, OCI company Ltd.) was added to 200 ml of distilled water to adjust the pH to 13, and 10 g of the pulverized serpentine particles were added to a 1 L reaction vessel.

The reaction vessel was injected with carbon dioxide (CO ₂ ) gas at a pressure of 0.2 MPa and reacted for 1 hour with stirring at 100 ° C.

The slurry prepared above was separated from the solid and liquid portions using a centrifuge, that is, dehydrated, dried at a temperature of 90 ° C., and pulverized to obtain a white powder.

The prepared white powder was confirmed using an X-ray diffractometer, but it was confirmed that no cubic magnesium carbonate was produced by obtaining a graph of the same pattern as that shown in FIG.

Claims (3)

a) placing a serpentine particle having a particle size of 43 to 73 μm in a reactor and heat-treating at 600 to 800 ° C .;
b) mixing the mixture with heat-treated serpentine particles by adding an alkaline solution having a pH of 10 to 14 in the reactor;
c) injecting carbon dioxide (CO ₂ ) into the prepared mixture at 1 to 4 MPa, and preparing a slurry to produce a slurry containing cubic magnesium carbonate by carbonation at 100 to 250 ° C .;
The mixing weight ratio of the alkaline solution and the serpentine particles in step b) is 1: 0.01 to 0.1 method of producing a cubic magnesium carbonate. According to claim 1, After the step c), d) obtaining a cubic magnesium carbonate solid from the slurry prepared; cubic magnesium carbonate production method further comprising. delete

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