KR20130126437A - Method for preparation of magnesium oxide architectures with meso-macro pores - Google Patents

Abstract

Provided are a method for manufacturing a magnesium oxide structure and the magnesium oxide structure manufactured thereby. The magnesium oxide structure manufactured by a method according to the present invention has meso-macro pores and improves a surface area and strength, thereby providing a catalyst with improved catalyst activation. [Reference numerals] (AA) Mesoporous precursor;(BB) Additive;(CC) Powder mixture;(DD) Porous powder shaped article;(EE) Meso-macro porous structure;(FF) Inorganic binder

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method for preparing a magnesium oxide structure having meso-macropores,

The present invention relates to a method for producing a magnesium oxide structure that can be used as a catalyst carrier, an adsorbent such as carbon dioxide, and the like. To a method for producing a magnesium oxide structure having meso-macro pores.

Magnesium oxide, an insulator with a wide bandgap, is widely used in catalysts, carbon dioxide adsorbents, refractory materials, paints, and superconductors. Magnesium oxide with controlled nanostructures is most often obtained by thermal decomposition of various magnesium compounds such as hydroxides, oxalates, carbonates, nitrates and the like.

In general, the reactivity of solid materials depends on its chemical initial stage, and studies on magnesium oxide obtained through the decomposition pathways of various compounds such as magnesium hydroxide, magnesium carbonate, etc., indicate that they have a high activity for adsorption and catalysis . However, the bottom-up process, a method for obtaining nanostructured magnesium oxide for heterogeneous catalysis, still has room for improvement because it makes it difficult to control and reproducible use of nanostructures.

On the other hand, a catalyst carrier used for reactions such as Fischer-Tropsch synthesis, steam reforming and the like has a meso-macro structure in order to have high permeability of the reaction gas and high activity of the catalyst. ). ≪ / RTI > In addition, the catalyst carrier should have high strength for long-term use under high-temperature and high-pressure reaction conditions, and maintain the porous nanostructure. That is, in order to have a high strength of a catalyst support made of an inorganic material, it is necessary to sinter at a high temperature. In the case of sintering at a high temperature, the porous nanostructure formed to raise the catalytic reaction easily collapses and the macro- .

Therefore, there is a need to develop a method for producing a magnesium oxide structure capable of forming and maintaining a nanostructure having meso-macro-pores even at a high firing temperature.

SUMMARY OF THE INVENTION The present invention provides a method for producing a magnesium oxide structure having meso-macro-pores having high strength and large specific surface area.

Another object of the present invention is to provide a magnesium oxide structure manufactured by the above method.

It is another object of the present invention to provide a catalyst comprising the magnesium oxide structure produced by the above production method.

According to an aspect of the present invention,

Preparing a mesoporous magnesium oxide precursor powder;

Mixing the magnesium oxide precursor powder for mesopore formation with an inorganic binder to form a powder mixture; And

And forming and sintering the powder mixture. The present invention also provides a method of manufacturing a magnesium oxide structure having meso-macro-pores.

According to another aspect of the present invention,

A magnesium oxide structure having meso-macro-pores produced by the above method is provided.

According to another aspect of the present invention,

A magnesium oxide structure having meso-macro-pores prepared by the above method; And a catalyst active component supported on the structure.

According to another aspect of the present invention,

Supporting a precursor of a catalytically active component on a magnesium oxide structure having meso-macropores prepared by the above method; And

Heat treating the magnesium oxide structure supporting the catalytically active component precursor in a hydrogen gas atmosphere

And a magnesium oxide-supported catalyst.

The magnesium oxide structure having meso-macropore pores produced by the method according to one aspect of the present invention is characterized in that the supported catalyst has high permeability of the reaction gas and high specific surface area and high strength, separation of carbon dioxide, fixed adsorbent for adsorption, Can be provided.

FIG. 1 is a schematic view illustrating a process for manufacturing a magnesium oxide structure according to an embodiment of the present invention. Referring to FIG.
2A and 2B are FE-SEM photographs of the magnesium oxide precursor powder prepared in Example 1 and Example 2 of the present invention, respectively.
3 is an FE-SEM photograph of the surface of the magnesium oxide structure produced in Example 2 of the present invention.
FIG. 4 is a graph showing the pore diameter versus cumulative pore volume of the magnesium oxide structure prepared according to Example 2 of the present invention measured by the mercury porosimetry method. FIG.
5 is an FE-SEM photograph of the surface of a magnesium oxide-spinel composite carrier produced according to Example 3-1 of the present invention.
6 shows XRD analysis results of the magnesium oxide-spinel composite carrier prepared in Examples 3-1 and 3-2 of the present invention.
7 is an FE-SEM photograph of a catalyst carrying cobalt on the magnesium oxide carrier prepared in Example 7 of the present invention.
8 is an XRD analysis result of a catalyst carrying cobalt on the magnesium oxide carrier prepared in Example 8 of the present invention.
9A is an FE-SEM photograph of the nickel-supported magnesium oxide-spinel catalyst carrier surface prepared according to Example 8 of the present invention. FIG. 9B is an enlarged photograph of FIG. 9A. FIG.
10A is an FE-SEM photograph of a cobalt-supported magnesium oxide-spinel catalyst carrier prepared according to Example 9 of the present invention. 10B is an enlarged photograph of FIG. 10A.

Hereinafter, the present invention will be described in more detail.

According to an aspect of the present invention, there is provided a method of preparing a magnesium oxide structure having meso-macropores, comprising: preparing a magnesium oxide precursor powder for mesoporous formation; Mixing the magnesium oxide precursor powder for mesopore formation with an inorganic binder to form a powder mixture; And molding and sintering the powder mixture.

The mesoporous magnesium oxide precursor powder for use in the production method according to an embodiment of the present invention may be magnesium hydroxide, magnesium hydrogen carbonate, or magnesium carbonate powder. The mesoporous magnesium oxide precursor powder may be spherical, plate-like or cube-shaped having a size of 1 to 500 μm. The mesoporous magnesium oxide precursor powder for forming mesopores is then sintered to form mesopores in the magnesium oxide particles and to form macropores between the magnesium oxide particles to obtain a bimodal catalyst carrier having meso-macropores, A magnesium oxide structure having macropores, and a catalyst or an adsorbent containing the magnesium oxide structure.

In the method for preparing a catalyst carrier according to an embodiment of the present invention, the step of preparing the mesoporous magnesium oxide precursor powder may be carried out by using an inorganic acid salt such as nitrate, sulfate or carbonate of magnesium, an organic acid salt such as acetate, Magnesium complexes and the like in the supercritical carbon dioxide. The supercritical carbon dioxide treatment may be carried out at a pressure of 0.5 to 30 MPa at 30 to 300 캜. Supercritical carbon dioxide treatment is described in detail in Korean Patent Registration No. 1100297 of the present inventor and is incorporated herein by reference.

As another method, an inorganic acid such as nitrate, sulfate or carbonate of magnesium, organic acid salt such as acetate, magnesium hydrate or magnesium complex is dispersed in an organic solvent and then an aqueous alkaline solution such as aqueous ammonia is used to form a precipitate Treated with supercritical carbon dioxide at a temperature of 30 to 300 ° C. and a pressure of 0.5 to 30 MPa for 1 minute to 100 hours and then cooled and separated to obtain a magnesium oxide precursor powder for mesoporous formation can do.

When the mesoporous magnesium oxide powder is mixed with an inorganic binder, a precipitant may be added and mixed.

The method may further include a step of heat-treating the mesoporous magnesium oxide precursor powder for mixing with the inorganic binder and the precipitant before forming the powder mixture. Through this heat treatment, a certain degree of mesopores can be formed in the mesoporous magnesium oxide precursor powder in advance. In doing so, it is possible to prevent cracks which may occur in the subsequent sintering step. The heat treatment may be performed at 600 to 1400 ° C for 5 minutes to 48 hours. The step of forming the powder mixture may include: obtaining a mixed precipitate of a magnesium oxide precursor powder for mesoporous formation and an inorganic binder; And subjecting the precipitated mixture to solid-liquid separation. The mixed precipitate may be prepared by adding a magnesium oxide precursor powder for forming a mesopore to a solution containing an inorganic binder, then dropping the precipitant while stirring the mixed solution, or dispersing the magnesium oxide precursor powder in a solution containing the precipitant And adding the mixed solution to an aqueous solution containing an inorganic binder.

The inorganic binder used in the production method according to one embodiment of the present invention may be a metal hydroxide in the form of an inorganic gel. Examples thereof include magnesium hydroxide obtained by precipitating a metal salt such as magnesium nitrate, magnesium sulfate and magnesium chloride, aluminum hydroxide And metal hydroxides such as zinc hydroxide.

The inorganic binder can strongly bond the magnesium oxide precursor particles when forming the powder mixture into a bead or a pellet form to maintain the molding strength, and can maintain a high strength of the magnesium oxide structure even after sintering.

The mesoporous magnesium oxide precursor powder and the inorganic binder may be mixed in a weight ratio of 1: 9 to 99.9: 0.01. If it is within the above range, a magnesium oxide structure having meso-macropores can be produced.

The solution containing the inorganic binder can be obtained by dissolving the inorganic binder in water or an organic solvent. The organic solvent is preferably an alcohol-based solvent, more preferably methanol or ethanol, and is not particularly limited, but may be used in a concentration of 0.05 to 5 moles.

In the conventional method for preparing a catalyst carrier, an organic binder is used for binding of the catalyst carrier precursor powder and for retaining the porous nanostructure of the carrier. However, since the organic binder is burned at high temperature sintering, the porous nanostructure of the catalyst carrier is broken And as a result, the desired high strength catalyst carrier could not be produced.

However, in the present invention, by using an inorganic binder having high heat resistance, even after high-temperature sintering, the porous nanostructure of the catalyst carrier is maintained and the nanostructure is preserved even after the catalyst is supported, so that a supported catalyst having excellent catalytic activity can be obtained. That is, the inorganic binder acts as a base of the catalyst carrier to maintain the bond between the carrier particles, and also acts as a component forming the porous nanostructure. For example, when magnesium hydroxide is used as the inorganic binder and magnesium hydroxide and aluminum hydroxide are used together in the form of magnesium oxide finally, spinel or magnesium oxide and aluminum oxide are formed depending on the composition or temperature.

In addition, the present invention may further include an organic binder used in a conventional method.

The precipitant used in the production method according to an embodiment of the present invention may be ammonia water.

The powder mixture obtained above is molded and sintered to obtain a magnesium oxide structure having meso-macropore pores. In this case, the forming method is not particularly limited, and for example, a binder, water or an organic solvent may be added to the powder mixture to form a paste or a clay. As the binder, at least one of an inorganic binder and an organic binder may be used. As the inorganic binder, those previously used may be used. As the organic binder, any of those used in this technical field can be used without limitation. Examples of the inorganic binder include cellulose binders, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, gel binders gel-binder and starch may be used. In this case, the molding can be carried out by extrusion molding, pressure molding, coating on a processed sheet, or the like. A pellet-type extruder, a screw-type extruder, or the like, to easily form a bead shape, a pellet shape, a honeycomb shape, or the like.

If necessary, the molded product can be put into an antisolvent or a substitution solvent, that is, an organic solvent of an aromatic hydrocarbon such as dimethyl ether, toluene, or an alcohol-based organic solvent to control the moldability and drying speed.

After molding, if necessary, it is dried and then sintered at 800 to 1,300 ° C to form a magnesium oxide structure having meso-macro-pores. At this time, nitrogen gas can be used as the carrier gas. For example, the temperature is raised from 800 ° C. to 1,300 ° C. at a rate of 1 ° C. to 10 ° C. per minute from a room temperature in a nitrogen gas atmosphere, and is held for 30 minutes to 5 hours, and the temperature is lowered to room temperature again at 1 ° C. to 10 ° C. per minute.

In the method for producing a magnesium oxide structure having meso-macropore pores according to an embodiment of the present invention, the kind and concentration of the magnesium oxide precursor, the kind and shape of the metal compound powder produced by the supercritical reaction, the metal compound powder and the precipitate The pore structure and strength of the structure can be appropriately changed depending on the intended use.

FIG. 1 is a schematic view illustrating a process for producing a magnesium oxide structure having meso-macro-pores according to an embodiment of the present invention. Referring to FIG.

As shown in FIG. 1, when an inorganic binder and a precipitant are added to a spherical, plate or cube-shaped mesoporous magnesium oxide precursor powder, a powder mixture in which a magnesium oxide precursor for mesoporous formation is dispersed in an inorganic binder is obtained, And a magnesium oxide structure having meso-macro-pores in which macropores are formed in the particles and macropores are formed in the particles are obtained.

According to another aspect of the present invention, there is provided a magnesium oxide structure having meso-macropore pores produced by the above method. The magnesium oxide structure may be a catalyst carrier or an adsorbent.

In the magnesium oxide catalyst structure according to an embodiment of the present invention, the meso-macropore pores may include macropores existing between the mesopores existing in the magnesium oxide particles and the magnesium oxide particles. The mesopores may have a diameter of 2 to 50 nm and a pore volume of 0.05 to 2 cm 3 / g. The macropore may have a diameter of 50 to 5,000 nm and a pore volume of 0.05 to 20 cm 3 / g. By having the diameter and the volume in the above range, the catalytically active component can be easily positioned on the surface of the structure.

The magnesium oxide structure according to one embodiment of the present invention may have various shapes, for example, beads of a cylindrical or cubic shape, and may have a length of 0.5 to 10 mm.

According to another aspect of the present invention, there is provided a magnesium oxide structure having a meso-macropore pore prepared by the above method; And a catalyst active component supported on the structure.

The catalytically active component varies depending on the use of the catalyst and is not particularly limited and may be selected from the group consisting of Ni, Co, Ru, Rh, Cu, Ag, Au, Pt, Pd, Sb, Sc, Sr, V, Cu, A rare earth element such as Mo, W, Fe, Zr, Zn, Cd, Mn, Ca, Ba, Cs, Cr, Mg, Ti, Al, In, Sn, Se, Fe, Te, Ga, Gd, Ge, Ho, Lu, Tb, Eu, Nd, La, Ta, Hf, Er and Yb.

According to another aspect of the present invention, there is provided a method for preparing a catalyst, comprising: supporting a precursor of a catalytically active component on a magnesium oxide structure having meso-macropore pores produced by the method; And heat treating the magnesium oxide structure bearing the catalytically active component precursor in a hydrogen gas atmosphere.

The method for supporting the catalytically active component precursor is not particularly limited, and for example, a supporting method, a kneading method and the like can be used. Specifically, the step of impregnating the precursor of the catalytically active component with the solution containing the magnesium oxide structure and the step of drying may be repeated. In addition, the supporting step may be performed at atmospheric pressure or vacuum, and the drying may be performed using microwaves to increase the efficiency of supporting the catalytic active material.

In the method for producing the catalyst, the heat treatment step may be performed at 200 to 800 ° C.

In the method for producing a catalyst according to an embodiment of the present invention, after the catalytically active component or the precursor of the catalytically active component is supported on the catalyst layer, the precursor of the catalytically active component or the catalytically active component precursor is reacted with hydrogen, nitrogen, argon, helium, alcohol, methane, propane, isobutane Or reducing the catalytically active component with the carrier gas, which may help to control the size and shape of the catalyst particles by promoting the reaction with the catalytically active component or by inhibiting the reaction.

The catalyst may be excellent in catalytic activity because the catalytically active component is mainly present on the surface of the support.

The catalyst according to one embodiment of the present invention can be used in processes such as a Fischer-Tropsch (FT) process, a reforming process, a natural gas liquefaction (GTL) process, and a biocatalyst process.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these embodiments.

Example 1

25.6 g of magnesium nitrate hexahydrate (Mg (NO ₃ ) ₂ .6H ₂ O, 98%, Junsei) was dissolved in 1,000 ml of ethanol to obtain an ethanol solution of magnesium nitrate hexahydrate of 0.1 M concentration. The solution was placed in a supercritical reactor (self-made) capable of controlling the pressure and temperature, and a carbon dioxide fluid was injected at a flow rate of 24 cc / min while stirring. The reaction temperature was raised to 150 MPa and pressure was increased to 20 MPa, For 10 to 240 minutes. The supercritical reactor was then cooled to ambient temperature and the pressure was slowly drained to atmospheric pressure. The filtrate was separated from the reaction product and dried at a temperature of 100 DEG C or less to obtain a fine powder of a magnesium oxide precursor for mesoporous formation. The dried fine powder has a spherical or cubic shape and has a specific surface area of 1.5 to 87.7 m ² / g as measured by the BET method as shown in Table 1, and a specific surface area of 67.5 to 90.3 m ² / g after calcination at 600 ° C Specific surface area.

Table 1 shows the BET specific surface area of the magnesium oxide precursor powder prepared by varying the reaction temperature in the supercritical carbon dioxide treatment for obtaining the mesoporous magnesium oxide precursor powder and the BET specific surface area of the magnesium oxide powder after calcination at 600 ° C .

Reaction temperature (℃) BET (m ² / g) Average pore size (nm) Firearm Volume
(Cm3 / g) Magnesium oxide precursor Magnesium oxide
powder Magnesium oxide
powder 50 87.7 86.2 - - 80 78.7 79.1 - - 140 63.0 67.5 - - 150 3.4 78.2 2.4 0.245 180 2.1 90.3 2.4 0.291 200 1.5 70.6 2.5 0.185

By comparing the BET specific surface area of the magnesium oxide precursor and the BET specific surface area after sintering, it can be seen that the magnesium oxide precursor subsequently forms the mesopores of the magnesium oxide structure.

1.7 g of the spherical mesoporous magnesium oxide precursor powder obtained above was placed in 1,000 ml of a 0.1 M magnesium nitrate hexahydrate aqueous solution and stirred while a 1 M ammonia aqueous solution was added dropwise to the pH of the mixed solution to 8 to 11 to form a precipitate. The sludge - state powder mixture was obtained by centrifugation and solid - liquid separation. A cellulose binder and water were added to the powder mixture to prepare a paste, which was extruded to obtain a cylindrical bead-shaped molded body having a diameter of about 0.5 to 3 mm and a height of 0.5 to 5 mm.

The temperature of the molded powder mixture was raised from room temperature to 5 ° C per minute in a nitrogen gas atmosphere, maintained at 1,300 ° C for 1 hour, and further cooled down to room temperature at 5 ° C per minute. The specific surface area of the bead type magnesium oxide structure after firing was 40.3 m ² / g as measured by the BET method.

Example 2

The volume of the ammonia aqueous solution used in the preparation of the bead type magnesium oxide structure in Example 1 was measured. To the aqueous ammonia solution of 1 M in the same volume as the above, the cubic magnesium oxide precursor for mesoporous formation Magnesium oxide structure was obtained in the same manner as in Example 1, except that 1.7 g of the powder was added to 1,000 ml of 0.1 M magnesium nitrate hexahydrate aqueous solution with stirring to form a precipitate.

The specific surface area of the bead type magnesium oxide structure after firing was 49.8 m ² / g as measured by the BET method.

2A and 2B are FE-SEM photographs of the mesoporous magnesium oxide precursor powder prepared in Example 1 and Example 2 of the present invention, respectively. 2A is a spherical magnesium oxide precursor powder and FIG. 2B is a cube-shaped magnesium oxide precursor powder.

3 is an FE-SEM photograph of the surface of the magnesium oxide structure produced according to Example 2. Fig. As shown in FIG. 3, it can be confirmed that cube-shaped magnesium oxide having an inorganic binder as a matrix is well distributed.

FIG. 4 is a graph showing the pore diameter versus cumulative pore volume of the magnesium oxide structure prepared according to Example 2, measured by the mercury porosimetry method. As shown in FIG. 4, the magnesium oxide structure according to an embodiment of the present invention has a meso-macro pore distribution, and the mesopores (about 6-35 nm) and macropores (about 250-5,000 nm) You can see the two obvious maximum values. The average pore size (including mesopores and macropores), specific surface area and porosity were 2,425 nm, 49.8 m ² / g and 62.1%, respectively. From FIG. 4, it can be seen that a magnesium oxide structure having meso-macro pores was stably prepared.

Examples 3-1, 3-2, 3-3, and 3-4

The volume of the aqueous ammonia solution used in Example 1 was measured and 1.7 g of the cube-shaped magnesium oxide precursor powder prepared in Example 2 was added to a 1 M aqueous ammonia solution having the same volume as that of Example 1, Except that 1,000 ml of a mixed solution of 0.1 M of magnesium nitrate hexahydrate aqueous solution and 0.1 M of aluminum nitrate nonahydrate aqueous solution was added with stirring to form a precipitate. In Example 3-2 at 1,100 ° C, in Example 3-3 at 1,200 ° C, in Example 3-4 at 1,300 ° C And each was fired for 1 hour to obtain a magnesium oxide structure.

The specific surface area of the magnesium oxide structure after firing was 64.0, 45.0, 50 and 25.0 m ² / g after calcination at 1,000 ° C, 1,100 ° C, 1,200 ° C and 1,300 ° C, respectively, as measured by the BET method.

5 is a scanning electron microscope (FE-SEM, Hitachi, S-4100) of the surface of a magnesium oxide structure produced by the method of Example 3-1 of the present invention. As shown in FIG. 5, it can be seen that the magnesium oxide particles on the cube are well bonded by the inorganic binder, and the pores are formed between the cube-shaped particles.

FIG. 6 is a result of XRD analysis of a bead type magnesium oxide structure manufactured by firing at 1,100 ° C. and 1,200 ° C. according to Examples 3-2 and 3-3, respectively. As a result of X-ray analysis, only the magnesium oxide and spinel two phases were identified, and it was confirmed that the magnesium oxide particles on the cube had the magnesium oxide-spinel composite structure having the spinel phase inorganic binder as a matrix .

Example 4

Nickel nitrate hexahydrate was weighed so as to have a nickel content of 15 wt% with respect to the weight of the bead-shaped magnesium oxide carrier obtained in Example 1, and then impregnated with an alcohol solution having a molar concentration of 4.5 mol / L. Then, it was dried at 100 ° C using a microwave. The impregnation and drying step was repeated three times to infiltrate the precursor of the catalytically active substance.

The magnesium oxide beads carrying the catalytically active substance precursor were heated from room temperature to 5 ° C./minute in a mixed gas atmosphere of hydrogen and nitrogen at a volume fraction of 2: 1, maintained at 400 ° C. for 1 hour and then cooled down to room temperature at 5 ° C./minute To thereby reduce the catalytically active substance.

The specific surface area of the reduced nickel supported catalyst was 88.5 m ² / g as measured by the BET method.

Example 5

In Example 4, the precursor of the catalytically active substance was impregnated under the same supporting conditions using cobalt nitrate hexahydrate instead of nickel nitrate hexahydrate as a precursor of the catalytically active substance.

The magnesium oxide bead carrying the catalytically active substance precursor was heated from room temperature to 5 ° C per minute in a hydrogen gas atmosphere, maintained at 500 ° C for 5 hours, and cooled to room temperature at 5 ° C per minute to reduce the catalytically active substance.

The specific surface area of the reduced cobalt loaded catalyst was 120.27 m ² / g as measured by the BET method.

Example 6

A catalyst in which nickel was supported on the magnesium oxide structure was obtained in the same manner as in Example 4 except that the bead type magnesium oxide structure of Example 2 was used. The specific surface area of the reduced nickel supported catalyst was 105.6 m ² / g as measured by the BET method.

Example 7

A catalyst in which cobalt was supported on the magnesium oxide structure was obtained in the same manner as in Example 5 except that the bead type magnesium oxide catalyst support of Example 2 was used. The specific surface area of the reduced cobalt supported catalyst was 223.5 m ² / g as measured by the BET method. 7 is an FE-SEM photograph of a catalyst carrying cobalt on the magnesium oxide carrier prepared in Example 7 of the present invention. As shown in FIG. 7, it can be observed that an inorganic binder matrix of a three-dimensional nanoweb structure is formed between the magnesium oxide particles on the cube.

Fig. 8 shows XRD analysis results of a catalyst in which cobalt was supported on a magnesium oxide carrier in Example 7 of the present invention. As can be seen from FIG. 8, only the two main peaks of magnesium oxide and cobalt were confirmed, indicating that the cobalt nano-catalyst was well dispersed in the magnesium oxide carrier.

Example 8

A catalyst in which nickel was supported on the magnesium oxide structure was obtained in the same manner as in Example 6 except that the bead type magnesium oxide structure produced in Example 3-1 was used. The specific surface area of the reduced nickel supported catalyst was 85 m ² / g as measured by the BET method.

Example 9

A catalyst having cobalt supported on a magnesium oxide structure was obtained in the same manner as in Example 7, except that the bead type magnesium oxide structure produced in Example 3-1 was used. The specific surface area of the reduced cobalt supported catalyst was 104 m ² / g as measured by the BET method.

Example No. Catalytically active substance Specific surface area
(m ² / g) Total pore volume
(cm < ³ > / g) Average pore diameter
(nm) Example 1 - 40.3 0.2144 21.2 Example 2 - 49.8 0.2830 22.7 Example 3-1 -  64.0  0.2861  17.8 Example 3-2 -  45.0  0.1985  12.7 Example 3-3 - 50.0 0.1599 12.7 Example 3-4 - 25.0 0.1055 11.5 Example 4 nickel 88.5 0.3015 13.6 Example 5 cobalt 120.3 0.4684 15.6 Example 6 nickel 105.6 0.4065 15.7 Example 7 cobalt 223.5 0.7045 12.6 Example 8 nickel  101.0  0.2180  8.4 Example 9 cobalt  85.0  0.1331  6.2

From Table 2, it can be seen that when the catalytic active material is loaded on the magnesium oxide structure, the specific surface area and the total pore volume increase. In addition, it can be seen that the specific surface area of the magnesium oxide structure produced according to Example 2 is further increased, so that the structure made by the method of Example 2 can be more advantageous from the viewpoint of activity than Example 1. Further, it can be seen that the specific surface area is further increased when the catalytic active material such as nickel and cobalt is supported according to Examples 6 and 7, and therefore, the magnesium oxide produced by the methods of Examples 6 and 7 The metal catalyst supported on the beads may be advantageous in terms of activity. In terms of chemical stability, the magnesium oxide-spinel structures of Examples 8 and 9 may be advantageous over the magnesium oxide structures of Examples 6 and 7.

FIG. 9A is an FE-SEM photograph of the nickel-supported magnesium oxide-spinel catalyst surface prepared according to Example 8 of the present invention. FIG. FIG. 9B is an enlarged view of FIG. 9A by 3.5 times. As shown in FIG. 9A, it can be seen that nanoscale nickel nanoparticles are formed on the surface of the cube-shaped magnesium oxide carrier particles.

10A is an FE-SEM photograph of the surface of a magnesium oxide-spinel catalyst supported on cobalt prepared according to Example 9 of the present invention. As shown in Figs. 10A and 10B (an enlarged view of Fig. 10A), it is observed that the particles on the cube are strongly bonded by the inorganic binder of the nano-web structure and the cobalt nanoparticles are formed on the surfaces of the cube particles and the nano- can do.

While the preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Accordingly, the scope of protection of the present invention should be determined by the appended claims.

Claims (27)

Preparing a mesoporous magnesium oxide precursor powder;
Mixing the magnesium oxide precursor powder for mesopore formation with an inorganic binder to form a powder mixture; And
Forming and sintering the powder mixture;
A method for producing a magnesium oxide catalyst carrier having meso-macro pores. The method of claim 1,
Wherein the mesoporous magnesium oxide precursor powder is magnesium hydroxide, magnesium hydrogencarbonate or magnesium carbonate powder. The method of claim 1,
Wherein the inorganic binder is at least one selected from magnesium hydroxide, aluminum hydroxide and zinc hydroxide. The method of claim 1,
Wherein the step of preparing the mesoporous magnesium oxide precursor powder comprises treating supercritical carbon dioxide with magnesium nitrate. 5. The method of claim 4,
Wherein the supercritical carbon dioxide treatment is carried out at a pressure of 0.5 to 30 MPa at 30 to 300 占 폚. The method of claim 1,
Wherein the magnesium oxide precursor powder for mesopore formation is mixed with an inorganic binder by adding a precipitant. The method of claim 1,
The step of forming the powder mixture includes: obtaining a mixed precipitate of a magnesium oxide precursor powder for forming a mesopore and an inorganic binder; And subjecting the precipitated mixture to solid-liquid separation. The method of claim 1,
Wherein the precipitating agent is ammonia water. The method of claim 1,
Wherein the mesoporous magnesium oxide precursor powder and the inorganic binder are mixed at a weight ratio of 1: 9 to 99.9: 0.01. The method of claim 1,
Further comprising the step of heat treating the mesoporous magnesium oxide precursor powder prior to mixing the mesoporous magnesium oxide precursor powder with an inorganic binder and a precipitant to form a powder mixture. The method of claim 10,
Wherein the heat treatment is performed at a temperature of 700 to 1,300 DEG C for 10 minutes to 5 hours. The method of claim 1,
Wherein the mesoporous magnesium oxide precursor powder is spherical, plate-like or cubic. The method of claim 1,
Wherein the mesoporous magnesium oxide precursor powder has a size of 1 to 500 탆. The method of claim 1,
Wherein the sintering step is performed at 800 to 1300 占 폚. Magnesium oxide structure having meso-macro pores produced by the method according to any one of claims 1 to 14. 16. The method of claim 15,
A magnesium oxide structure further comprising spinel. 17. The method according to claim 15 or 16,
The meso-macro pores are magnesium oxide structure comprising meso pores present in the particles and macro pores present between the particles. 18. The method of claim 17,
Wherein the mesopores have a diameter of 2 to 50 nm and a pore volume of 0.05 to 2 cm < 3 > / g. 18. The method of claim 17,
Wherein the macropore has a diameter of 50 to 5,000 nm and a pore volume of 0.05 to 20 cm < 3 > / g. 16. The method of claim 15,
A magnesium oxide structure in the form of a cylindrical or cubic bead. A magnesium oxide structure having a mezo-macropore pore according to claim 15; And
And a catalytically active component supported on the structure. The method of claim 21,
Wherein the catalytically active component is at least one selected from the group consisting of Ni, Co, Pt, Pd, Rh, Cu, Fe, Ag and Au. Supporting a catalytically active component precursor on a magnesium oxide structure having meso-macropores according to claim 15; And
Heat treating the magnesium oxide structure supporting the catalytically active component precursor in a hydrogen gas atmosphere
Wherein the magnesium oxide-supported catalyst is a magnesium oxide-supported catalyst. 24. The method of claim 23,
Wherein the step of impregnating the catalytically active component precursor with the solution containing the magnesium oxide structure and the step of drying are repeated. 24. The method of claim 23,
Wherein the supporting step is carried out at atmospheric pressure or vacuum. 24. The method of claim 23,
Wherein the drying is performed using microwave. 24. The method of claim 23,
Wherein the heat treatment is performed at a temperature of 200 to 800 캜.

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