KR20110075323A - Method of water gas shift reaction and method for producing hydrogen using the same - Google Patents

Abstract

PURPOSE: A method for reacting aqueous shift gas and a method for manufacturing hydrogen using the same are provided to simplify operational processes by replacing two-shift reactors with one reactor. CONSTITUTION: Carbon monoxide is reacted with water under the catalyst in a perovskite structure in order to obtain hydrogen and carbon dioxide. The catalyst in the perovskite structure is represented by general formula 1. In the general formula 1, the A is La, Y, Pr, Gd, or Sm. The A' is Na, K, Ca, Sr, Ba, Ga, or Ce. The B is Ni, Co, Cu, Zn, Fe, Ga, Al, Cr, Mn, Ti, V, Mo, W, Zr, Nb, or Sn. The B' is Ru or Rh. The x is between 0 and 1, and the y is between 0 and 0.5. The carbon monoxide is supplied from by-product gases. An aqueous gas shift reaction is implemented in a single reactor at temperature between 400 and 450 degrees Celsius.

Description

Aqueous shift gas reaction method and hydrogen production method using the same {METHOD OF WATER GAS SHIFT REACTION AND METHOD FOR PRODUCING HYDROGEN USING THE SAME}

The present invention relates to an aqueous shift gas reaction method and a hydrogen production method using the same. More specifically, by using a perovskite structure catalyst in the aqueous shift gas reaction, a single CO reactor has a higher CO conversion rate than in the related art. The present invention relates to an aqueous shift gas reaction method and a method for producing hydrogen using the same, which have a low initial investment and low cost.

Recently, hydrogen is receiving a lot of attention as an environment-friendly / high efficiency energy source. Accordingly, research on a technology capable of producing a large amount of hydrogen is being actively conducted. Hydrogen can be produced from a variety of raw materials (naphtha, LNG, Coal, etc.), but among these, the process of producing hydrogen from coal, which is relatively rich in reserve resources, has received much attention.

On the other hand, by-product gas generated in the process of processing coal in steel mills and the like contains a large amount of carbon monoxide, and when the carbon monoxide reacts with water, a water gas shift reaction occurs and hydrogen gas is generated. . The reaction scheme of the water gas shift reaction is as follows.

[Reaction Scheme]

CO + H ₂ O → CO ₂ + H ₂ , -40.1KJ / mol

The hydrogen production method is commercialized by applying the above water gas shift reaction, and a catalyst for water gas shift reaction has been developed and used to obtain higher yield. In order to increase the CO conversion rate of the water gas shift reaction, the hydrogen production method to which the conventional water gas shift reaction is applied is different from each other suitable for a high temperature range of about 400 ° C to 500 ° C and a low temperature range of about 200 ° C to 250 ° C. A two-stage reaction using a catalyst is used. A Fe / Cr-based catalyst is used in the high temperature region and a Cu / Zn-based catalyst is used in the low temperature region.

However, in the conventional hydrogen production method, since two reactors must be configured, the facility investment cost is high, and pyrophoricity when the Fe / Cr catalyst and the Cu / Zn catalyst are exposed to the atmosphere. ), There is a problem that handling is difficult.

The present invention has been made to solve the above problems, and an object thereof is to provide an aqueous gas shift reaction and a hydrogen production method capable of obtaining excellent conversion even with a single reactor.

To this end, the present invention provides a water gas shift reaction method for producing hydrogen and carbon dioxide by reacting carbon monoxide and water in the presence of a perovskite structure catalyst.

In another aspect, the present invention provides a hydrogen production method for producing hydrogen using an aqueous gas shift reaction that reacts carbon monoxide with water in the presence of a perovskite structure catalyst to produce hydrogen and carbon dioxide.

In this case, the perovskite structure of the catalyst is preferably represented by the following formula (1).

Equation (1): (A _1-x A _x ') (B _1-y B _y ') O _{3 ± e}

Wherein A is La, Y, Pr, Gd or Sm

A 'is Na, K, Ca, Sr, Ba, Ag or Ce

B is Ni, Co, Cu, Zn, Fe, Ga, Al, Cr, Mn, Ti, V, Mo, W, Zr, Nb or Sn

B 'is Ru or Rh,

0 <x <1,

0 <y <0.5.

In addition, the carbon monoxide may be supplied from the ironworks by-product gas, the water gas shift reaction is preferably carried out at 400 ℃ ~ 450 ℃. In addition, the water gas shift reaction is preferably carried out in a single reactor.

As in the present invention, when using a perovskite catalyst, it is possible to obtain excellent CO conversion at a high temperature as compared with the conventional catalyst for water gas shift reaction. Therefore, the conventional two-stage reactor can be replaced with one reactor, so that the initial investment cost can be reduced and the process can be simplified.

In addition, since the perovskite catalyst has no spontaneous ignition unlike a conventional catalyst for water gas shift reaction, there is an advantage in that it is easy to handle.

Hereinafter, the present invention will be described more specifically.

As described above, the present invention relates to a water gas shift reaction method for reacting carbon monoxide and water to produce hydrogen and carbon dioxide, characterized in that the reaction proceeds in the presence of a catalyst of perovskite structure.

The water gas shift reaction is a reaction for generating carbon dioxide and hydrogen by reacting carbon monoxide and water, and can be expressed as in the following scheme.

[Reaction Scheme]

CO + H ₂ O → CO ₂ + H ₂ , -40.1KJ / mol

As described above, various catalysts have been researched and developed to improve the CO conversion of the water gas shift reaction. However, most of the catalysts for water gas shift reactions developed in the related art have difficulty in obtaining a desired conversion rate when used alone, and have a problem in that different catalysts have to be used depending on the temperature range in order to obtain a desired conversion rate. The present inventors have steadily studied to solve such a problem, and found that when the catalyst for the aqueous gas shift reaction is used as the catalyst for the perovskite structure, a high conversion rate can be obtained with only a single catalyst. The present invention has been completed.

The catalyst of the perovskite structure is a mixed metal oxide generally represented by the general structural formula of ABO ₃ , and a general perovskite structure is shown in FIG. 1. In the perovskite structure as shown in FIG. 1, since most metals are stable, various compositions are possible, and show various electric, magnetic, and optical properties depending on the metal used. Therefore, it is possible to prepare a catalyst having a desired performance by adjusting the component and composition ratio.

In this invention, it is especially preferable to use the catalyst represented by following formula (1) among the catalysts of a perovskite structure.

Equation (1): (A _1-x A _x ') (B _1-y B _y ') O _{3 ± e}

At this time, in Formula (1), A is La, Y, Pr, Gd or Sm, A 'is Na, K, Ca, Sr, Ba, Ag or Ce, B is Ni, Co, Cu, Zn, Fe , Ga, Al, Cr, Mn, Ti, V, Mo, W, Zr, Nb or Sn, B 'is Ru or Rh, satisfies 0 <x <1, and satisfies 0 <y <0.5 desirable.

On the other hand, the method for producing a catalyst of the perovskite structure as described above can be prepared through a method well known in the art, for example, glycine-nitrate (GNP) process. That is, the perovskite structure of the catalyst can be prepared by dissolving metal nitrate and glycine in deionized water, heating it to form a powder, and calcining the powder.

The aqueous gas shift reaction of the present invention may be performed by supplying carbon monoxide and water filled with a catalyst of perovskite structure prepared by the above method and proceeding with the reaction. At this time, it is preferable that the said reaction temperature is about 400 degreeC-450 degreeC. When the reaction proceeds in the above temperature range in the presence of a catalyst of perovskite structure, an optimum CO conversion can be obtained.

As can be seen in the examples below, the perovskite structure catalyst of the present invention shows a very good conversion in the above temperature range. Therefore, when using a perovskite structure catalyst as in the present invention, there is no need to use a two-stage reactor as in the prior art, and a sufficient conversion rate can be obtained with only a single reactor.

On the other hand, the present invention can be supplied from the ironworks by-product gas carbon monoxide used as a raw material of the water gas shift reaction. By-product gases in steel mills contain large amounts of carbon monoxide. Therefore, when it is used as a raw material of the water gas shift reaction, the raw material costs and by-product gas treatment costs such as steel mills can be reduced, as well as environmentally friendly.

The present invention also provides a hydrogen production method for producing hydrogen using an aqueous gas shift reaction in which carbon monoxide and water are reacted to generate hydrogen and carbon dioxide in the presence of a perovskite structure catalyst.

At this time, it is preferable to use a catalyst represented by the following formula (1) as the catalyst of the perovskite structure, the catalyst of the perovskite structure, for example, can be produced through a GNP process.

Equation (1): (A _1-x A _x ') (B _1-y B _y ') O _{3 ± e}

At this time, in Formula (1), A is La, Y, Pr, Gd or Sm, A 'is Na, K, Ca, Sr, Ba, Ag or Ce, B is Ni, Co, Cu, Zn, Fe , Ga, Al, Cr, Mn, Ti, V, Mo, W, Zr, Nb or Sn, B 'is Ru or Rh, satisfies 0 <x <1, and satisfies 0 <y <0.5 desirable.

On the other hand, in the hydrogen production method, the water gas shift reaction is preferably carried out in a temperature range of 400 ℃ ~ 450 ℃, unlike the prior art is preferably performed in a single reactor.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

Example

A perovskite catalyst in the form of Sm _0.9 Ba _0.1 Cr _0.95 Ru _0.05 O ₃ was synthesized with a uniform chemical composition using a Glycine-Nitrate Process (GNP). The GNP method is a method for synthesizing a substance by exothermic reaction by dissolving metal nitrate and glycine as fuel in deionized water and heating. The powder produced after heating was calcined at 800 ° C. for 1 hour in an air atmosphere. The catalyst prepared by the above method was in powder form, which was pressed into a mold for pellet production, crushed, and prepared into catalyst particles between 250 and 425 μm using a sieve.

Comparative Example 1

For comparison, the Sud Chemi's Cu / Zn-based catalyst in pellet form was crushed to prepare catalyst particles between 250 and 425 μm using a sieve and used in the experiment.

Comparative Example 2

For comparison, pellets of Sud Chemi's Fe / Cr based catalyst were crushed to prepare catalyst particles between 250 and 425 μm and used in the experiment.

Experimental Example

The reaction apparatus was configured as shown in FIG. 2 to measure WGS (Water Gas Shift) reaction activity of the catalysts of Examples, Comparative Examples 1 and 2. The experimental apparatus consists of a part for quantitatively supplying each reactant, a part carrying a reactant, a reactor installed in an electric furnace, and a water removing part for gas chromatograph (GC) analysis. Syngas, which simulates the by-product gas of steel mills, was manufactured by a professional manufacturer, and a form filled in a high pressure cylinder was used. As the water used for the water gas shift reaction, tertiary deionized water (specific resistance of 15 MPa / cm or more) produced using a deionized water maker was used.

WGS reactant syngas and water were fed to a reactor installed in an electric furnace to proceed with the reaction. At this time, the reactants were supplied at a gas hourly space velocity (GHSV) of 3000 ~ 5000 / h.

Syngas was metered into the reactor using a Mass Flow Controller (MFC). Water was quantitatively supplied using a High Performance Liquid Chromatography (HPLC) pump and evaporated in an evaporator located in a temperature controlled sand bath and then transferred to the reactor in gaseous state, using nitrogen as a carrier gas. . In FIG. 2, the part shown with a thick line shows the tube heated using the heating wire and wrapped with the heat insulation so that evaporated water does not condense on the way.

On the other hand, after the respective catalysts of Examples, Comparative Examples 1 and 2 were respectively installed in the reactor, the WGS reaction was carried out while controlling the temperature of the reactor. Then, the reaction products generated from each reactor were collected for each temperature and analyzed by GC (Gas Chromatograph). Samples were removed by passing through a condenser and a moisture trap to remove moisture and then analyzed by gas chromatograph (GC).

As a result of component analysis, the CO conversion rate according to the temperature when the catalysts of Examples, Comparative Example 1 and Comparative Example 2 were used was shown as shown in FIG. As shown in FIG. 3, it can be seen that when the catalyst of the example is used, the CO conversion rate is remarkably superior to Comparative Examples 1 and 2.

1 is a view showing a perovskite structure.

2 is a view for explaining an experimental apparatus and an experimental method of the experimental example of the present invention.

3 is a view showing the carbon monoxide conversion rate according to the reaction temperature when using the catalysts of Examples and Comparative Examples 1 and 2.

Claims (10)

A water gas shift reaction method for producing hydrogen and carbon dioxide by reacting carbon monoxide and water in the presence of a catalyst of perovskite structure. The method of claim 1, The perovskite structure catalyst is represented by the following formula (1). Formula (1) (A _1-x A _x ') (B _1-y B _y ') O _{3 ± e} Where A is La, Y, Pr, Gd or Sm A 'is Na, K, Ca, Sr, Ba, Ag or Ce B is Ni, Co, Cu, Zn, Fe, Ga, Al, Cr, Mn, Ti, V, Mo, W, Zr, Nb or Sn B 'is Ru or Rh, 0 <x <1, 0 <y <0.5. The method of claim 1, The carbon monoxide is a water gas shift reaction method is supplied from the ironworks by-product gas. The method of claim 1, The water gas shift reaction is carried out at 400 ℃ ~ 450 ℃ water gas shift reaction method. The method of claim 1, Wherein the water gas shift reaction is carried out in a single reactor. A method for producing hydrogen, wherein the hydrogen is produced using an aqueous gas shift reaction in which carbon monoxide and water are reacted in the presence of a perovskite structure catalyst to produce hydrogen and carbon dioxide. The method of claim 6, The perovskite structure catalyst is hydrogen production method represented by the following formula (1). Formula (1) (A _1-x A _x ') (B _1-y B _y ') O _{3 ± e} Where A is La, Y, Pr, Gd or Sm A 'is Na, K, Ca, Sr, Ba, Ag or Ce B is Ni, Co, Cu, Zn, Fe, Ga, Al, Cr, Mn, Ti, V, Mo, W, Zr, Nb or Sn B 'is Ru or Rh, 0 <x <1, 0 <y <0.5. The method of claim 6, The carbon monoxide is a hydrogen production method is supplied from the ironworks by-product gas. The method of claim 6, The water gas shift reaction is hydrogen production method carried out at 400 ℃ ~ 450 ℃. The method of claim 6, Wherein said water gas shift reaction is carried out in a single reactor.

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