KR102015299B1 - Catalysts for reforming bio-gas and methods of manufacturing the same - Google Patents

Abstract

Monolithic supports of a hierarchically porous structure; And it is supported on the support, there is provided a biogas reforming catalyst comprising a compound represented by the following [Formula 1].
[Formula 1]
Sr _1-y Y _y Ti _1-x Ru _x O _3-δ
(Where x is greater than 0 and less than 1. y is greater than 0 and less than 0.1. Δ is greater than 0 and less than 1).

Description

Catalyst for biogas reforming and its manufacturing method {CATALYSTS FOR REFORMING BIO-GAS AND METHODS OF MANUFACTURING THE SAME}

The present invention relates to a catalyst for biogas reforming and a method for preparing the same. More specifically, the present invention relates to a catalyst for dry reforming of bio-gas and a method for producing the same.

Fuel cells, which are in the spotlight as one of the alternatives to fossil fuels, have limited use because they rely heavily on hydrogen production and storage technology. Therefore, research on the hydrogen production method has been actively conducted, and the most economical and environmentally friendly method of the hydrogen production method developed so far is to use a methane reforming reaction using biogas generated from biomass. In particular, in order to prevent energy loss due to the use of steam, a dry reforming reaction using direct methane and carbon dioxide contained in biogas may be used, rather than steam reforming. In the case of the dry reforming reaction, a process for separating carbon dioxide by using a direct reforming reaction using carbon dioxide does not require a separate process, thereby maximizing efficiency.

Generally, nickel-based catalysts are used for the dry reforming reaction, and precious metal catalysts (Ru, Rh, Pd, etc.) are mainly used in order to increase the efficiency of dry reforming. Development is urgent. Therefore, it is essential to develop a catalyst that efficiently decomposes methane and carbon dioxide and resists carbon deposition.

In order to solve this problem, research on the use of a catalyst having a perovskite structure for biogas reforming instead of a noble metal catalyst has been conducted. However, in this case, the catalytic activity is lower than the catalyst using the precious metal. Accordingly, there is still a need for a new catalyst development.

Korean Patent Application No. 10-2013-0133251 Korean Patent Application No. 10-2012-0108535 Korean Patent Application No. 10-2002-0079657

One object of the present invention is to have a high resistance to carbon deposition, high activity and maintain high activity even when the fuel cell using the catalyst is long-term operation, biogas reforming, in particular biogas containing methane and carbon dioxide It is to provide a catalyst for biogas reforming, and a method for producing the same, which can easily produce a synthesis gas including hydrogen, carbon monoxide, etc. during dry reforming.

In one embodiment of the present invention, a monolithic support having a hierarchically porous structure; And it is supported on the support, there is provided a biogas reforming catalyst comprising a compound represented by the following [Formula 1].

[Formula 1]

Sr _1-y Y _y Ti _1-x Ru _x O _3-δ

(Where x is greater than 0 and less than 1. y is greater than 0 and less than 0.1. Δ is greater than 0 and less than 1).

In an exemplary embodiment, x in Chemical Formula 1 may be greater than 0 and less than or equal to 0.05.

In an exemplary embodiment, y in Formula 1 may be greater than 0 and less than or equal to 0.08.

In an exemplary embodiment, the biogas reforming catalyst may be a single phase homogeneous catalyst.

In an exemplary embodiment, the compound represented by [Formula 1] may be supported in the pores of the monolith support.

In an exemplary embodiment, the compound represented by [Formula 1] may be supported by 10 to 50 parts by weight based on 100 parts by weight of the monolith support.

In an exemplary embodiment, the biogas reforming catalyst may exhibit a methane conversion of at least 80% during 60 to 80 hours of operation at a temperature of 750 ~ 900 ℃.

In an exemplary embodiment, the catalyst for biogas reforming may be for biogas dry reforming.

In one embodiment of the present invention, in the production method of the catalyst for biogas reforming, doping substitution of a portion of strontium (Sr) in the perovskite (perovskite) material represented by the following [Formula 2] with yttrium (Y) Preparing a compound represented by the above [Formula 1] by doping and substituting a part of titanium (Ti) with ruthenium (Ru); And coating a compound represented by the above [Formula 1] on a monolithic support to prepare a catalyst for biogas reforming.

[Formula 2]

SrTiO ₃

In an exemplary embodiment, the partially doped substitution of the perovskite material with yttrium (Y) and ruthenium (Ru) comprises yttrium (Y), strontium (Sr), titanium (Ti) and ruthenium ( As a solvent for dissolving a compound including Ru), distilled water or deionized water (DIion water) may be used through the Pechini method.

In an exemplary embodiment, after partially doping and replacing the perovskite material with yttrium (Y) and titanium (Ti), the catalyst represented by [Formula 1] is hydrogen, nitrogen, helium and argon It may include the activation process to one or more selected from the group consisting of.

In an exemplary embodiment, the activation treatment may be performed at 750 ° C. to 900 ° C. using hydrogen as the inert gas.

In an exemplary embodiment, the step of coating the compound represented by [Formula 1] on the monolithic (monolithic) support may be performed through a dip coating.

The catalyst for biogas reforming according to the embodiments of the present invention has high catalytic activity despite having less precious metal catalyst than conventional noble metal catalysts, and has excellent resistance to carbon deposition, and thus high It can maintain the activity and proceed with dry reforming reaction using biogas (including carbon dioxide) in large capacity. Thereby, the synthesis gas with a high hydrogen ratio can be manufactured easily with high activity for a long time.

Furthermore, since the biogas reforming catalyst according to the present invention is manufactured through the Pechini method using distilled water or deionized water (DI water) in the manufacturing method thereof, it contains substantially impurities. And can be prepared with a single phase homogeneous catalyst.

In addition, in the biogas reforming catalyst according to the present invention, since the compound represented by Formula 1 is supported on the monolith support through a simple dip coating method, it is possible to manufacture the catalyst very economically and efficiently. In addition, the biogas reforming catalyst according to the present invention, there is an advantage that can be produced without increasing the pressure.

1 is a flow chart showing the flow of the method for producing a biogas reforming catalyst according to an embodiment of the present invention.
2 is an X-ray diffractiometry (XRD) graph of a biogas reforming catalyst according to an embodiment of the present invention and a catalyst according to a comparative example.
3A to 3C are images of the surface of the biogas reforming catalyst according to Comparative Example 3, Example 1, and Example 6 observed with a scanning electron microscope (SEM).
4a to 4c are images of the surface of the biogas reforming catalyst prepared according to Examples 1 to 3 and Examples 6 to 8 with a scanning electron microscope (SEM).
5 is a graph showing the results of experiments on the methane conversion rate according to the operating time in the biogas reforming catalyst according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention disclosed in the text are only illustrated for illustrative purposes, and the embodiments of the present invention may be embodied in various forms and should not be construed as being limited to the embodiments described in the text. .

The present invention may be modified in various ways and may have various forms, and the embodiments are not intended to limit the present invention to the specific disclosed forms, and all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention. It will be understood to include.

Bio-gas in the embodiment of the present invention, biomass such as sewage sludge, food waste (biomass) that can be produced through anaerobic digestion (anaerobic digestion), gasification, and pyrolysis Gaseous fuel. This biogas contains methane (55-70%) and carbon dioxide (30-45%) as main components, and contains impurities such as sulfur (S).

In the embodiment of the present invention, the dry reforming reaction refers to a reaction for producing carbon monoxide and hydrogen by reacting carbon dioxide and methane. Dry reforming reactions are useful in terms of carbon dioxide reuse, and are endothermic and therefore low in reaction. For reference, Scheme 1 below is a scheme of dry reforming of carbon dioxide.

Scheme 1

CH ₄ + CO ₂ ↔ 2CO + 2H ₂ (△ H ₂ = +247 kJ / mol)

In an embodiment of the present invention, a homogenous catalyst refers to a catalyst capable of maintaining a single phase by including an active material substituted in a material lattice.

In the embodiments of the present invention, the long-term stability of the catalyst is the conversion or hydrogen selectivity of the catalyst (molar ratio of generated hydrogen to fuel consumed in the reaction), i.e., the ability to maintain the catalyst activity for a long time higher than the required level. Means. Thus, improved long-term stability of the catalyst means improved lifetime of the catalyst.

In the embodiment of the present invention, the Pechini method is broadly used for chelation between the acid contained in the polymer resin (citric acid) and the cations dissolved in the solvent, and the metal-chelate complex and polyhydroxyalcohol ( By means of polymerization between titanium isopropoxide), it means a powder synthesis method in which a cation is dispersed to obtain a chemically uniform and stable precursor.

In the exemplary embodiment of the present invention, hierarchically porous structures include two or more pores of different sizes simultaneously among micropores (<2nm), mesopores (2-50 nm), and macropores (> 50 nm). It means a porous structure.

In an embodiment of the present invention, dip-coating refers to a method of dipping a coated material in a coating solution or slurry to coat a precursor on the coated material and baking at an appropriate temperature to form a coating film. In an embodiment of the present invention, a monolith support, which is a coating material, is coated on a perovskite catalyst solution made by Pechini's method and then calcined at about 650 ° C. to prepare a catalyst.

In an embodiment of the invention, 'monolith support' means a support of the catalyst, which is cylindrical. But not limited to, the monolith support may comprise a ceramic, metal, alumina, silica, alumina, titanate (titanate alumina), cordierite _{(Codierite) (2MgO.2Al 2 O 3} .5SiO 2) or the like.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Embodiments of the present invention have been described with reference to the accompanying drawings, which are described for purposes of illustration, whereby the technical idea of the present invention and its configuration and application are not limited.

Catalysts for Biogas Dry Reforming

The catalyst of the present invention is a catalyst for biogas reforming, more specifically, a dry reforming of bio-gas including methane and carbon dioxide, and a monolithic support having a hierarchically porous structure. ; And a compound supported on the monolith support and represented by the following [Formula 1].

[Formula 1]

Sr _1-y Y _y Ti _1-x Ru _x O _3-δ

(Where x is greater than 0 and less than 1. y is greater than 0 and less than 0.1. Δ is greater than 0 and less than 1).

For reference, when yttrium (Y) and ruthenium (Ru) are doped in the perovskite lattice structure of SrTiO ₃ , a slight change may occur in the O content by the doped metal. That is, in [Formula 1] O ₃ of the perovskite may be finely changed to O _3-δ (δ is 0 to 1 or less).

The compound is a part of the perovskite material represented by SrTiO ₃ (Sr) is doped substituted by yttrium (Y) and part of titanium (Ti) doped substituted by ruthenium (Ru). That is, in the perovskite material having the structure of ABO ₃ , the compound includes a part of A site (Sr) and a part of B site (Ti) as different materials (R at Y and B at A), respectively. By doping substitution, the perovskite structure can be maintained.

Thus, unlike conventional catalysts are generally so-called heterogeneous catalysts which are prepared by heat treating the active material on a support and consist of two or more phases, the compound is a single phase homogeneous catalyst when used as a catalyst. It can act as a homogeneous catalyst. Therefore, the catalyst containing the compound can be prepared through a minimized synthesis process is more useful in terms of process efficiency and economics than conventional catalysts.

Of these compounds, Ru (ruthenium) substituted at the titanium site (B site of the perovskite structure) has high catalytic activity. In addition, yttrium (Y) substituted at the strontium site (A site in the perovskite structure) can provide improved electrical conductivity to the catalyst. Moreover, since the perovskite catalyst having the structure of ABO ₃ inherently has excellent resistance to sulfur (S) and carbon (C), the biogas reforming catalyst including the compound has a high resistance to biogas reforming reaction. It may have catalytic activity and may also have high resistance to carbon deposition and / or catalyst poisoning.

In particular, when the catalyst is used in dry reforming, where carbon dioxide is directly added to the reforming reaction by selectively removing carbon dioxide contained in the biogas, the carbon dioxide is directly used in the reforming reaction, and a separate carbon dioxide separation process is not additionally required. Therefore, the effect can be maximized.

In exemplary embodiments, substitution of the titanium site (B site of the perovskite structure), considering both the maintenance of a single phase of the catalyst, prevention of carbon deposition and / or catalyst poisoning, maintenance of the catalyst activity and improved electrical conductivity It is preferable that the amount of ruthenium (Ru), ie, x in Formula 1, is greater than 0 and less than or equal to 0.05 (0 <x ≦ 0.5). In particular, it may be preferred if x is 0.03. In addition, the amount of yttrium (Y) substituted at the strontium site (A site in the perovskite structure), that is, y is greater than 0 and less than or equal to 0.08 (0 <y≤0.08), in particular, y is 0.08 It may be desirable.

When y is 0.08 in [Formula 1], it is considered that the electrical conductivity is the best while maintaining a single phase. However, in this case, if x is 0, that is, there is no substitution of ruthenium at the titanium site, the catalytic activity becomes very low. However, when x is substituted even a small amount (for example, x = 0.01), x = 0.02, 0.05, 0.1. Similar to the above, it can be seen that it shows a very high degree of reforming performance.

In exemplary embodiments, the biogas reforming catalyst may be activated using an inert gas including nitrogen (N), helium (He), argon (Ar), or the like, or reduced using hydrogen (H). It may be activated in an atmosphere. In particular, the catalyst may be activated in a reducing atmosphere, the reactant can be chemisorbed to the active site by removing the oxygen attached to the catalyst surface in the reducing atmosphere.

On the other hand, the compound represented by [Formula 1] may be supported on a monolithic (monolithic) support, specifically, can be supported through a dip-coating (dip-coating) process. When performing dip-coating, the compound represented by the above [Formula 1] may be more easily coated.

In an exemplary embodiment, the material that may be included in the monolithic support is not limited as long as it is a material that can be included in the existing monolithic support, for example, alumina, silica, alumina titanate (alumina) titanate), it may include cordierite _{(Codierite) (2MgO.2Al 2 O 3} .5SiO 2) or the like.

In addition, the monolithic support may have a hierarchically porous structure, and in this case, a plurality of pores having various sizes are formed in the support, and the compound represented by [Formula 1] may be supported in a large amount. have.

In an exemplary embodiment, the specific surface area of the monolith support may be in the range of 34 to 37 cm ² / cm ³ .

On the other hand, with respect to 100 parts by weight of the monolith support, the compound represented by [Formula 1] may be supported by 10 to 50 parts by weight, specifically, may be supported by 20 to 45 parts by weight. When it is supported by less than 10 parts by weight, the performance deterioration phenomenon occurs due to lack of catalyst active point, and if it exceeds 50 parts by weight, the performance of the catalyst may be reduced due to mass transfer limitation.

As described above, the biogas reforming catalyst according to the present invention includes a compound represented by the formula (1) supported on a monolith support having a multi-stage pore structure, and has a very good catalytic performance during the reforming reaction of biogas including carbon dioxide. Can be seen.

In an exemplary embodiment, the biogas reforming catalyst may exhibit a catalyst performance of 80% or more during 60 to 80 hours of operation at a temperature of 750 ~ 900 ℃. Specifically, the biogas reforming catalyst may exhibit a methane conversion of 83% or more during a 70 hour operation at 750 ° C.

Method for producing catalyst for biogas dry reforming

The catalyst according to the exemplary embodiments of the present invention is doped with a portion of strontium (Sr) of yttrium (Y) in the perovskite material represented by the following [Formula 2], and part of titanium (Ti) Preparing a compound represented by [Formula 1] by doping substitution with ruthenium (Ru); And preparing a catalyst for biogas reforming by coating the compound represented by Chemical Formula 1 on a monolithic support. It may be prepared through a method for producing a biogas reforming catalyst comprising a.

[Formula 2]

SrTiO ₃

In an exemplary embodiment, the partially doped substitution of the perovskite material with yttrium (Y) and ruthenium (Ru) comprises yttrium (Y), strontium (Sr), titanium (Ti) and ruthenium ( Using distilled water or deionized water (DI water) as a solvent for dissolving the compound including Ru), it can be carried out through the Pechini method (Pechini method) of the known dry catalyst preparation method.

More specifically, yttrium nitrate [Y (NO ₃ ) ₃ .H ₂ O] and strontium nitrate [Sr (NO ₃ ) ₃ .H ₂ O] are dissolved in distilled or deionized water (DI water) to prepare a first solution. do. Titanium isopropoxide [Ti (OCH (CH ₃ ) ₂ ) ₄ ] and citric acid are sufficiently dissolved in ethylene glycol to prepare a second solution. Ruthenium chloride [(Cl ₃ Ru.xH ₂ O)] is dissolved in distilled or deionized water (DI water) to prepare a third solution. At this time, the compounds of yttrium (Y), strontium (Sr), titanium (Ti) and ruthenium (Ru) are dissolved in distilled water or DI water rather than ethanol as in the prior art, thereby increasing the impurity content in the prepared catalyst. It can be minimized.

The first solution, the second solution, and the third solution thus prepared are mixed together, sufficiently stirred at about 80 ° C., and dried at about 110 ° C. to prepare a compound represented by Chemical Formula 1.

Meanwhile, after the compound represented by Chemical Formula 1 is prepared, calcination may be performed at a temperature of about 300 ° C. or more and 450 ° C. or less. The calcination process may be performed by one or more times, for example, by performing a first calcination process at about 300 ° C., and by performing a second calcination process at about 450 ° C. Accordingly, it is possible to effectively remove the organic matter that can be generated during the catalyst production.

The processes described above are a Pechini method using distilled or deionized water (DI water) as a solvent.

Accordingly, a gel solution including the compound represented by Chemical Formula 1 may be prepared through the above-described process.

Thereafter, the gel solution may be dip coated on a monolith support, and the compound represented by Chemical Formula 1 may be supported on the monolith support to prepare a catalyst for biogas reforming.

In exemplary embodiments, the dip coating of the gel solution may be achieved by coating a monolith support, which is a coating material, on a Sr _1-y Y _y Ti _1-x Ru _x O _3-δ catalyst solution made by Pechini method. It is fired at about 600 to 700 ℃, and thus, the compound represented by the formula (1) may be supported in a greater amount on the monolith support.

On the other hand, it is possible to control the amount of the catalyst by repeatedly performing the dip coating process. Such a dip coating process has the advantage of saving time or money in a simple manner that does not require complex or large equipment such as vacuum coating or pyrolysis coating.

Thereafter, the activated biogas reforming catalyst may be activated to improve the activity of the catalyst.

In exemplary embodiments, the activation treatment may be performed using an inert gas such as nitrogen, argon, helium, or using a nitrogen balance gas containing hydrogen. In particular, the activation treatment can be carried out under a reducing atmosphere. In the reducing atmosphere, the reactants can be chemisorbed at the active site by removing oxygen adhering to the catalyst surface.

In one embodiment, the activation treatment may be carried out at 750 ℃ to 900 ℃, specifically 800 to 850 ℃ using hydrogen. If the activation process is carried out below the above range may be ineffective catalytic activity improvement, if the activation process is carried out above the range may be rather deteriorate the performance of the catalyst.

As described above, the biogas reforming catalyst prepared according to exemplary embodiments of the present invention may include a material having a perovskite structure supported on a monolith support. Accordingly, since a compound having a greater amount of catalytic activity can be supported on the catalyst support than in the related art, the catalytic activity of the catalyst can be further improved.

For example, when the compound represented by Chemical Formula 1 is Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ (that is, when ruthenium is doped at 3 mol%) and is doped with a monolith support, simple Sr _0.92 Y _0.08 Ti _0.95 Ru _0.05 O _3-δ It can exhibit equivalent to good catalytic activity. Accordingly, high catalytic activity can be exhibited even when a small amount of the noble metal catalyst is used.

In addition, when preparing the catalyst for biogas reforming, an adhesive, a binder, or a pore-forming agent is not used, and thus catalyst activity may be maintained without poisoning by organic matter of the catalyst.

In addition, since the catalyst according to the exemplary embodiments of the present invention is prepared through the Pechini method using distilled water or deionized water (DI water) as a solvent, it is substantially free of impurities. It can be prepared with a single phase homogeneous catalyst.

In addition, when the catalyst is prepared for the catalyst activity, when the activation process is performed only with hydrogen under a reducing atmosphere, it may be prepared to have high catalyst activity and long-term stability.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not to be construed as limited by these embodiments.

Example

Example 1

3.064 g of yttrium nitrate [Y (NO ₃ ) ₃ .H ₂ O (Aldrich)] and 19.469 g of strontium nitrate [Sr (NO ₃ ) ₃ .H ₂ O (Aldrich)] were simultaneously dissolved in DI water. 28.13 g of titanium isopropoxide [Ti (OCH (CH ₃ ) ₂ ) ₄ (Aldrich)] and 76.8 g of citric acid were sufficiently dissolved in 200 g of ethylene glycol, followed by ruthenium chloride [(Cl ₃ Ru.xH ₂ O) (Junsei). 0.622 g was dissolved in DI water for stabilization. Each solution was mixed together at 80 ° C. for 24 hours to prepare a gel solution containing Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ (Ru doped 3%). Subsequently, 0.2 g of Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ may be supported on a monolith support (manufactured by Corning FLORA ^™ ) and then dried at 110 ° C. Finally, heat treatment was performed at 650 ° C. for 5 hours. Thus, a catalyst (hereinafter referred to as Ru-SYT coated monolith) containing Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ supported on a monolith support was prepared.

Example 2

In Example 1, the same process was carried out except that the monolith support (manufactured by Corning FLORA ^™ ) was dip coated to carry 0.1 g of Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ .

Example 3

In Example 1, the same process was carried out except that the monolith support (manufactured by Corning FLORA ^™ ) was dip coated to carry 0.3 g of Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ .

Example 4

In Example 1, after the Ru-SYT coated monolith was prepared, the same process was performed except that activation was performed at 750 ° C using a nitrogen balance gas containing hydrogen.

Example 5

In Example 1, after the Ru-SYT coated monolith was prepared, the same process was performed except that activation was carried out at 800 ° C. using a nitrogen balance gas containing hydrogen).

Example 6

In Example 1, after preparing Ru-SYT coated monolith, the same process was carried out except that the activation process at 850 ℃ using a nitrogen balance gas containing hydrogen.

Example 7

In Example 2, after the Ru-SYT coated monolith was prepared, the same process was performed except that activation was performed at 850 ° C using a nitrogen balance gas containing hydrogen.

Example 8

In Example 3, after preparing Ru-SYT coated monolith, the same process was performed except that the activation process was performed at 850 ° C using a nitrogen balance gas containing hydrogen.

 Comparative Example 1

3.064 g of yttrium nitrate [Y (NO ₃ ) ₃ .H ₂ O (Aldrich)] and 19.469 g of strontium nitrate [Sr (NO ₃ ) ₃ .H ₂ O (Aldrich)] were simultaneously dissolved in DI water. . 28.13 g of titanium isopropoxide [Ti (OCH (CH ₃ ) ₂ ) ₄ (Aldrich)] and 76.8 g of citric acid were sufficiently dissolved in 200 g of ethylene glycol, followed by ruthenium chloride [(Cl ₃ Ru.xH ₂ O) (Junsei). 0.622 g was dissolved in DI water for stabilization. Each solution was mixed together at 80 ° C. for 24 hours, dried at 110 ° C., and calcined at 400 ° C. in air to remove organics. Finally, heat treatment was performed at 650 ° C. for 5 hours. Accordingly, Ru was prepared with a catalyst of 3% doped Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ (hereinafter referred to as Ru3-SYT (powder)).

Comparative Example 2

3.064 g of yttrium nitrate [Y (NO ₃ ) ₃ .H ₂ O (Aldrich)], 19.469 g of strontium nitrate [Sr (NO ₃ ) ₃ .H ₂ O (Aldrich)], titanium isopropoxide [Ti (OCH ( Example 3, except that 27.6 g of CH ₃ ) ₂ ) ₄ (Aldrich), 76.8 g of citric acid, 200 g of ethylene glycol, and 1.088 g of ruthenium chloride [(Cl ₃ Ru.xH ₂ O) (Junsei)] were used. The same processes were performed to give Sr ₀ with 5% doped Ru _{. 92} Y _{0 . 08} Ti _{0 . 95} Ru _{0 .} A catalyst of ₀₅ O _{3 -δ} (hereinafter referred to as Ru5-SYT (powder)) was prepared.

Comparative Example 3

A monolith support (from Corning FLORA ^™ ) was used as Comparative Example 3.

Experimental Example 1: Evaluation of Composition of Catalyst

In order to evaluate the composition of the catalyst, X-ray diffraction (X RD) was performed on the catalysts according to Example 1, Comparative Example 1 and Comparative Example 3. The result is as shown in FIG.

Referring to FIG. 2, the catalysts according to Example 1, Comparative Example 1 and Comparative Example 3 have a perovskite structure of SrTiO ₃ as a basic structure, and part of strontium (Sr) is yttrium (Y) and titanium (Ti). It can be seen that some are homogeneous catalysts in single phase each doped and substituted with nickel (Ru). Through this, the catalyst of the present invention is a homogeneous catalyst of a single phase represented by the above [Formula 1], which can be easily prepared through the Pechini method (Pechini method) using distilled water or deionized water instead of ethanol as a solvent. It can be seen.

Experimental Example 2: Evaluation of Catalyst Performance with or Without Catalyst Activation

In order to evaluate the performance of the catalyst with or without catalyst activation, the catalysts prepared according to Comparative Example 3, Example 1 and Example 6 were used in the dry reforming reaction of the carbon dioxide-containing biogas. At this time, the surface of the catalyst before and after the dry reforming reaction was observed with a scanning electron microscope (SEM). The result is as shown in Figs. 3a to 3c.

3A to 3C, in the case of the catalyst prepared according to Example 1 (FIG. 3B), a large number of pore structures were generated compared to the monolith support (FIG. 3A). On the other hand, in the case of the catalyst prepared according to Example 6 (FIG. 3C), it can be seen that the porous structure is better formed than the catalyst prepared according to Example 1 in which no activation treatment is performed.

Experimental Example 3: Evaluation of Change in Pore Structure of Catalyst According to Supported Amount of Compound

In order to evaluate the performance of the catalyst according to the catalyst activation conditions, the surface of the catalyst prepared according to Examples 1 to 3 and Examples 6 to 8 was observed with a scanning electron microscope (SEM). The result is as shown in Figs. 4A to 4C.

4a to 4c, in the case of catalysts prepared according to Examples 6 to 8 (bottom of each figure), compared to catalysts prepared according to Examples 1 to 3 where no activation treatment was performed (in each figure Top) It was confirmed that the porous structure is significantly more excellent. Accordingly, it was confirmed that the catalyst activated in the reducing atmosphere increases the channel through which the gas flows due to the sintering phenomenon and thus increases the catalytic activity performance.

However, in Example 7, as the amount of _{Sr 0 .92 Y 0 .08 Ti 0} .97 Ru 0 .03 O 3 -δ small, performance degradation occurs due to lack of catalyst activity, and as shown in Example 8 When the amount of Sr _0.92 Y _0.08 Ti _0.97 Ru _0.03 O _3-δ is greater than 0.2 g, it can be seen that a slight performance degradation occurs due to mass transfer limitation. As a result, and confirmed that the most appropriate case in which the _{Sr 0 .92 Y 0 .08 Ti 0} .97 Ru 0 .03 O 3 -δ 0.2g supported on a monolith support.

Experimental Example 4: Evaluation of Performance of Catalyst According to Activation Treatment Temperature

In order to evaluate the performance of the catalyst according to the catalyst activation conditions, the catalyst prepared according to Examples 4 to 6 was used for the dry reforming reaction of the carbon dioxide containing biogas. The results are as shown in Table 1 below.

Activation temperature (℃) Loading amount of Ru3-SYT (g) Methane conversion rate (%) Example 4 750 0.2 10 Example 5 800 0.2 20 Example 6 850 0.2 83

Looking at the table, it was determined that the methane conversion rate is the lowest when the activation temperature is 750 ℃, and as the activation temperature is higher, the catalyst-activated catalyst in the reducing atmosphere increases the channels through which gas can flow due to the sintering phenomenon. It was confirmed that the catalytic activity performance is increased accordingly. In particular, in the case of Example 6, the activation temperature is 850 ℃ it was confirmed that the catalytic activity performance is significantly increased.

Experimental Example 5: Evaluation of Catalyst Performance of Catalyst According to Supported Amount

In order to evaluate the performance of the catalyst according to the supported amount of the compound represented by [Formula 1], the catalysts prepared according to Comparative Examples 1 to 3 and Examples 1 to 3 were used for the dry reforming reaction of the carbon dioxide-containing biogas. The results are as shown in Table 2 below.

catalyst Loading amount of Ru3-SYT (g) Methane conversion rate (%) Comparative Example 1 Ru3-SYT (powder) 0.2 73 Comparative Example 2 Ru5-SYT (powder) 0.2 83 Comparative Example 3 Monolith support 0 0 Example 2 Ru3-SYT / Monoris Support 0.1 64 Example 1 Ru3-SYT / Monoris Support 0.2 83 Example 3 Ru3-SYT / Monoris Support 0.3 80

Looking at the table, it was confirmed that the case of carrying the Ru3-SYT on the monolith support (Examples 1 to 3), the methane conversion rate is much higher than the other cases. In addition, looking at Examples 1 to 3, it can be seen that methane conversion rate increases as the amount of Ru3-SYT is generally increased. However, when the amount of the supported amount is small, the performance deterioration occurs due to the lack of catalyst active point, and the amount of the supported amount is less than 0.2 g. It was found that the higher the amount, the lower the performance due to mass transfer limitation.

Experimental Example 6: Performance Evaluation of Catalysts of Methane Conversion Rate During Long Time Operation

In order to evaluate the performance of the catalyst according to the long time operation, the catalyst prepared according to Example 1 was used for the dry reforming reaction of the biogas containing carbon dioxide. The results are shown in FIG.

Referring to FIG. 5, when the catalyst prepared according to Example 1 is used, even after the reaction is performed for 70 hours or more, the catalyst performance is maintained even though the reaction time for which the catalyst is used is long due to high resistance to carbon deposition. Could confirm. Accordingly, by maintaining high activity even when the fuel cell using the catalyst is operated for a long time, the synthesis gas containing hydrogen, carbon monoxide, etc. during biogas reforming, especially dry reforming of biogas containing methane and carbon dioxide, can be facilitated. It could be confirmed that it can be manufactured.

Claims (13)

As a catalyst for biogas reforming,
Monolithic supports of a hierarchically porous structure; And
It is supported on the support, and includes a compound having a perovskite structure represented by the following [Formula 1],
The biogas reforming catalyst is a single phase homogeneous catalyst,
The compound represented by the following [Formula 1] is supported by 10 to 50 parts by weight based on 100 parts by weight of the monolith support,
The catalyst is a biogas reforming catalyst having a sintered channel on the surface.
[Formula 1]
Sr _1-y Y _y Ti _1-x Ru _x O _3-δ
(Where x is greater than 0 and less than 1. y is greater than 0 and less than 0.1. Δ is greater than 0 and less than 1). The method of claim 1,
x is greater than 0 and less than or equal to 0.05 biogas reforming catalyst. The method of claim 2,
y is greater than 0 and 0.08 or less, the catalyst for biogas reforming. delete The method of claim 1,
A catalyst for biogas reforming, wherein a compound represented by the above [Formula 1] is supported in pores of the monolith support. delete The method of claim 1,
The biogas reforming catalyst is a biogas reforming catalyst exhibiting a methane conversion of 80% or more during the operation of 60 to 80 hours at a temperature of 750 ~ 900 ℃. The method of claim 1,
The biogas reforming catalyst is a biogas reforming catalyst for dry reforming biogas. In the method for producing a biogas reforming catalyst according to claim 1,
In the perovskite material represented by [Formula 2], a portion of strontium (Sr) is doped by yttrium (Y), and a portion of titanium (Ti) is doped by ruthenium (Ru), thereby replacing Preparing a compound represented by 1]; And
And coating a compound represented by the above [Formula 1] on a monolithic support to prepare a catalyst for biogas reforming.
10 to 50 parts by weight of the compound represented by [Formula 1] is supported based on 100 parts by weight of the monolith support,
After partially doping and replacing the perovskite material with yttrium (Y) and titanium (Ti), the catalyst represented by [Formula 1] is one selected from the group consisting of hydrogen, nitrogen, helium and argon Including the above activating treatment, the activated catalyst is a method of producing a catalyst for biogas reforming, the surface is sintered so that the channel through which gas can flow compared to before the activation treatment.
[Formula 2]
SrTiO ₃ The method of claim 9,
Partial doping substitution of the perovskite material with yttrium (Y) and ruthenium (Ru),
Pechini method using distilled or deionized water (DI water) as a solvent for dissolving a compound containing yttrium (Y), strontium (Sr), titanium (Ti) and ruthenium (Ru) To be carried out through, the production method of the catalyst for biogas reforming. delete The method of claim 9,
The activation process is to be carried out at 750 ℃ to 900 ℃ using a gas containing hydrogen as an inert gas, biogas reforming method for producing a catalyst. The method of claim 9,
Coating the compound represented by [Formula 1] on a monolithic (monolithic) support is to be carried out through a dip coating, a method for producing a catalyst for biogas reforming.

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