JP5105709B2 - Water gas shift reaction catalyst - Google Patents

Description

  The present invention relates to a novel water gas shift reaction catalyst that can be used for a long period of time.

In recent years, fuel cells have attracted attention as a power generation system that uses clean hydrogen as an energy source and generates no greenhouse gases such as CO _{2 with} no pollution. Such fuel cells have been fully developed and researched for use in fixed facilities such as homes and offices, and mobile facilities such as automobiles.

  Fuel cells are classified according to the electrolyte used, and are classified into alkaline electrolyte type, solid polymer electrolyte type, phosphoric acid type, molten carbonate type, and solid electrolyte type. At this time, in the solid polymer electrolyte type and the phosphoric acid type, the charge transfer body is proton and is also called a proton type fuel cell, and the present invention belongs to this proton type fuel cell.

Examples of the fuel used in the fuel cell include hydrocarbon fuels such as natural gas, LP gas, city gas, alcohol, gasoline, kerosene, and light oil.
Such hydrocarbon fuel is first converted into hydrogen gas and CO gas by a reaction such as steam reforming and partial oxidation, and the CO gas is removed to obtain hydrogen gas. This hydrogen is supplied to the anode, dissociated into protons (hydrogen ions) and electrons by the metal catalyst of the anode, the electrons flow to the cathode while working through the circuit, and the protons (hydrogen ions) diffuse through the electrolyte membrane and become the cathode. In the cathode, water is generated from electrons, hydrogen ions and oxygen supplied to the cathode, and diffuses into the electrolyte membrane. That is, it is a mechanism for taking out an electric current in the process of supplying water with oxygen and hydrogen derived from fuel gas.

  By the way, when the removal of the CO gas in the hydrogen gas is insufficient, there is a problem that the metal catalyst of the anode is poisoned and deactivated. In particular, when the fuel cell is operated at a low temperature, for example, near room temperature, the catalyst is completely deactivated even by the presence of tens of ppm or less of CO. Also, safety problems have been pointed out even when they are not completely deactivated.

For this reason, it has been required to remove the CO gas concentration in the hydrogen gas to at least several ppm level.
Conventionally, as a CO gas removal technique, a cryogenic separation method, a PSA method, an organic / metal membrane separation method, etc. have been proposed, but it is said that there are advantages and disadvantages in terms of CO removal level, compactness, durability, cost, etc. Yes. On the other hand, a method of selectively oxidizing CO by adding a small amount of oxygen to the reformed gas has been studied, and various active components have been proposed. For example, although it has been reported that about 100 to 200 ppm of CO can be tolerated by using a Pt—Ru alloy catalyst, it has been pointed out that there is a safety problem.

Up to now, a catalyst in which metal fine particles are supported as an active component on a metal oxide support has been proposed as a CO gas removal catalyst. (Patent Document 1 (Japanese Patent Publication No. 5-34284), Patent Document 2 (Japanese Patent Publication No. 6-20559), Patent Document 3 (Japanese Patent Publication No. 6-29137), Patent Document 4 (Japanese Patent Laid-Open No. 8-295502). Gazette))
In addition, Debora J, Myers et al, Electrochemical Technology Program, American Institute of Chemical Engineers March 10-14, 2002 (Non-patent Document 1) discusses a glycine-nitric acid method as a method for preparing a support for a water gas shift catalyst. Yes. Specifically, cerium nitrate and a ceria doping agent (zirconium or the like) are dissolved in water, and glycine is mixed therewith. The mixture is heated to evaporate the water and rapidly oxidize the nitrate compound. The produced powder is calcined in air at 800 ° C. for 2 hours to prepare a uniformly doped ceria powder having a specific area of 30 to 60 m ² / g. An active metal such as Pd or Co is supported on this powder to prepare a water gas shift catalyst. And it has been reported that the water gas shift catalyst obtained in this way has high activity.

Japanese Patent Application Laid-Open No. 64-27645 (Patent Document 5) discloses a shift catalyst comprising metallic copper and zinc oxide and / or magnesium oxide and having a copper metal surface area of at least 70 m ² per gram of copper. It is disclosed that such a catalyst uses 0.3 to 2.5 atoms of zinc oxide and / or magnesium oxide with respect to 1 copper atom.

Further, JP 2000-126597 A (Patent Document 6) discloses a catalyst for low-temperature carbon monoxide conversion reaction composed of copper oxide, zinc oxide and silicon oxide.
Japanese Examined Patent Publication No. 5-34284 Japanese Examined Patent Publication No. 6-20559 Japanese Patent Publication No. 6-29137 JP-A-8-295502 Debora J, Myers et al, Electrochemical Technology Program, American Institute of Chemical Engineers March 10-14, 2002 Japanese Unexamined Patent Publication No. 64-27645 JP 2000-126597 A

  However, as in Patent Documents 1 to 4, the conventional catalyst produced by the precipitation method or the coprecipitation method with the support component and the active metal component is a fine particle with non-uniform size of metal fine particles deposited on the surface. Large particles coexist with each other, or it is difficult to adjust to an optimum particle size that varies depending on the use conditions.For this reason, fine particles aggregate or grow during use and cause a decrease in activity. Originally, there were problems such as low activity efficiency of metal fine particles, insufficient catalyst life, inferior metal utilization efficiency and economical efficiency.

  In addition, although the catalyst of Non-Patent Document 1 contains both crystalline ceria and a crystal of doping component oxide and the activity is improved, performance varies greatly every time the catalyst is manufactured, and is not necessarily used for a long period of time. There was a case that I could not stand.

In addition, the catalyst described in Patent Document 5 is insufficient in activity as a water gas shift catalyst because copper sintering (sintering) is likely to occur.
The conversion catalyst described in Patent Document 6 has a drawback that it cannot be used for a long period of time due to the influence of generated water, probably because zinc oxide is used. That is, the water resistance was insufficient.

Under such circumstances, the appearance of a water gas shift reaction catalyst having high activity and excellent water resistance has been desired.
In view of the above-mentioned problems, the inventors of the present application have intensively studied and found that a catalyst having high activity and sustaining for a long time can be obtained by combining an active metal element and an alkaline earth metal oxide. .

  The water gas shift reaction catalyst according to the present invention contains at least one element selected from Cu, Ni, Co and Sn and an alkaline earth metal oxide, and the content of the element is 40 to 80 in terms of oxide. It is in the range of% by weight, the content of the alkaline earth metal oxide is 1 to 10% by weight, and the balance is an inorganic oxide other than the above.

The molar ratio (Mae) / (Mam) between the number of moles of the alkaline earth metal oxide (Mae) and the number of moles of the oxide of the element (Mam) is in the range of 0.01 to 0.2. preferable.
The inorganic oxide is preferably at least one selected from alumina, silica, zirconia, and titania.

It is preferable that the alkaline earth metal oxide is magnesia.
The inorganic oxide is preferably alumina.

  According to the present invention, it comprises a specific active metal element and an alkaline earth metal oxide, and since it contains a predetermined amount of alkaline earth metal oxide, it has a small effect on water and is excellent in water resistance. It is possible to provide a water gas shift reaction catalyst that can be used over a wide range.

First, the water gas shift reaction catalyst according to the present invention will be described.
Water Gas Shift Reaction Catalyst The water gas shift reaction catalyst according to the present invention contains at least one element selected from the group consisting of Cu , Ni, Co, and Sn as an active metal and an alkaline earth metal oxide.

[Active metal elements]
As the active metal element, an element selected from the group consisting of Cu , Ni, Co, and Sn is used. These elements are usually contained in the catalyst as oxides at the time of catalyst preparation, and are used after being reduced to metals when acting as a shift reaction catalyst.

The reduced active metal is usually in the form of fine particles. The average particle diameter of the metal fine particles is preferably in the range of 1 to 500 nm, more preferably 2 to 200 nm.
Within this range, the surface area of the metal fine particles is high and high activity can be maintained.

It is difficult to obtain a metal fine particle having a small average particle diameter, and even if it is obtained, the stability may be small, and the activity may decrease with time.
If the average particle size of the metal fine particles is too large, the surface area of the metal fine particles is reduced, and the activity may be insufficient.

The average particle diameter of the metal fine particles in the catalyst is measured as follows.
The water gas shift reaction catalyst was charged into a stainless steel reaction tube, after 30 minutes hydrogen reduction at the catalyst layer temperature 250 ° C., the catalyst layer was maintained at 60 ° C., to pulsing the N ₂ O gas. In the first and second pulses, chemisorption occurs and then becomes smaller than the pulse area. This was continued until the pulse area did not change, and the amount obtained by subtracting the first and second small areas from that area was taken as the amount of chemisorption. Obtained by the following formula.
(1) Calculation parameters V _cham / mol · g ⁻¹ : Chemical adsorption amount MW: Supported metal atomic weight σ _m / nm ² : Supported metal cross section SF: Stoichiometry (assumed 1)
c / wt%: supported metal amount ρ / g · cm ^-3 : supported metal density (2) calculation formula metal dispersity, Dm /% = chemical adsorption site / number of supported metal atoms × 100
= V _cham · SF · MW / (c / 100) × 100
Metal surface area (per gram of catalyst)
A _m (m ² / g) = V _cham・ 6.02 × 10 ²³・ SF ・ σ _m・ 10 ^-18
Metal surface area (per gram of supported metal)
A _m (m ² / g) = V _cham・ 6.02 × 10 ²³・ SF ・ σ _m・ 10 ^-18・ 100 / c
Average particle size S _m (nm) = 2r × 10 ⁹ = 6c / (A _m × 100 × ρ × 10 ⁶ ) × 100 × 10 ⁹
= 60c / (A _m × ρ)
The reduction process will be described later.

[Alkaline earth metal oxides]
As the alkaline earth metal oxide, one or more alkaline earth metal oxides selected from BeO, MgO, CaO, SrO, BaO, and RaO are used. Of these, MgO is preferable because it has a high effect of improving water resistance.

  When the content of the alkaline earth metal oxide in the water gas shift reaction catalyst is less than 1% by weight as an oxide, the effect of improving the water resistance is not sufficiently obtained. When the content exceeds 10% by weight as an oxide, the activity tends to decrease.

Alkaline earth metal oxides may be simply mixed with or complexed with oxides of active metal elements.
[Inorganic oxide]
The water gas shift reaction catalyst of the present invention further contains an inorganic oxide in addition to the active metal element and the alkaline earth metal oxide. As the inorganic oxide, one or more selected from alumina, silica, zirconia, and titania are preferable.

When these inorganic oxides (including composite inorganic oxides and mixed inorganic oxides) are contained, a water gas shift reaction catalyst having a high specific surface area and high activity can be obtained.
Among them, alumina is preferable because it has a high specific surface area catalyst when it is a composite oxide with an oxide of an active metal element and an alkaline earth metal oxide, and exhibits an excellent activity and water resistance. It is.

[composition]
In the water gas shift reaction catalyst according to the present invention, the content of the active metal element as an oxide is in the range of 40 to 80% by weight, and the content of the alkaline earth metal oxide is in the range of 1 to 10% by weight. . In the normal state, the catalyst according to the present invention may be a mixture of oxides or a composite oxide, which is reduced during use to metallize the active metal element.

The content of the active metal element in the water gas shift reaction catalyst is more preferably in the range of 45 to 75% by weight in terms of oxide.
If the content of the active metal element is in the above range as an oxide, the water gas shift reaction activity can be increased. When the content of the active metal element is small, the water gas shift reaction activity becomes insufficient. If the content of the active metal element is too large, the content of alkaline earth metal oxides and inorganic oxides will decrease, resulting in insufficient water resistance (insufficient alkaline earth metal oxides), and insufficient activity. (Inorganic oxide shortage).

  The molar ratio (Mae) / (Mam) of the number of moles (Mae) of the alkaline earth metal oxide and the number of moles (Mam) as the oxide of the active metal element is 0.01 to 0.2, Furthermore, it is preferable that it exists in the range of 0.02-0.15. When the molar ratio is in the above range, a water gas shift reaction catalyst having high heat resistance can be obtained.

  If the molar ratio (Mae) / (Mam) is small, the amount of the alkaline earth metal oxide is too small, so that the effect of improving water resistance may not be sufficiently obtained. When the ratio (Mae) / (Mam) is too large, the activity of the catalyst tends to decrease.

Although the mechanism of improving the water resistance when the molar ratio (Mae) / (Mam) is within the above range is not necessarily clear, the alkaline earth metal oxide interacts with water vapor (condensed water) rather than the active metal. Therefore, it is considered that the sintering of active metal is suppressed, the water resistance of the inorganic oxide is improved, and the water gas shift reaction is promoted by the combination of water vapor with the alkaline earth metal oxide. .

  Further, the content of the inorganic oxide in the water gas shift reaction catalyst is desirably in the range of 10 to 59% by weight, more preferably 20 to 50% by weight as the oxide. If it exists in the said range, the specific surface area of a catalyst will become small and a highly active catalyst can be obtained. When the content of the inorganic oxide is small, the specific surface area of the catalyst is decreased, and the activity may be insufficient. Moreover, when there is too much content, an active metal oxide and an alkaline-earth metal oxide will decrease, and activity and water resistance may become inadequate.

The water gas shift reaction catalyst according to the present invention as described above has a specific surface area of 50 to 300 m ² / g.
Furthermore, it is preferable that it exists in the range of 100-300 m < ² > / g. Within this range, high catalytic activity is exhibited.

  The catalyst is appropriately formed into a desired shape and then subjected to reduction treatment before use. For example, it may be processed into a sheet or hardened into a lump. Further, it may be formed into a desired shape such as a honeycomb, cylinder, or bead.

Catalyst Production Method The above-described water gas shift catalyst can be produced by a known method.
Specifically, an active metal compound solution of Cu, Ni, Co, and Sn is mixed with an alkaline earth metal compound solution, and a compound that induces an inorganic oxide, and an acid / alkali are added to neutralize the solution.・ Hydrolysis is sufficient.

  First, an aqueous solution of copper, nickel, cobalt, and tin compounds (salts, organic salts, complex salts), which are active metal element materials, is prepared. Copper, nickel, cobalt and tin compounds include copper nitrate, copper sulfate, copper chloride, copper acetate, nickel nitrate, nickel sulfate, nickel chloride, nickel acetate, cobalt nitrate, cobalt sulfate, cobalt chloride, cobalt acetate, An alkoxide etc. are mentioned.

  The concentration of the active metal compound aqueous solution is not particularly limited, but is preferably in the range of 0.5 to 15% by weight, more preferably 1.0 to 5.0% by weight as an oxide. In such a concentration range, mixing with the alkaline earth metal oxide raw material aqueous solution and the added inorganic oxide raw material aqueous solution is uniform, the specific surface area is high, and the activity and water resistance are excellent. A water gas shift reaction catalyst can be obtained.

  Examples of alkaline earth metal compounds include magnesium nitrate, magnesium chloride, magnesium sulfate, calcium nitrate, calcium chloride, calcium sulfate, strontium nitrate, strontium chloride, strontium sulfate, calcium, magnesium, organic salts of each alkaline earth metal, alkoxide, etc. Is mentioned.

The concentration of the alkaline earth metal compound aqueous solution is preferably 0.1 to 15% by weight, more preferably 1.0 to 5.0% by weight as an oxide.
Furthermore, water-soluble compounds are desirable as the compounds for deriving inorganic oxides to be used as needed. Specifically, aluminum nitrate, aluminum sulfate, sodium aluminate, aluminum chloride, sodium silicate, zirconium nitrate oxide, sulfate oxidation Zirconium, titanium sulfate, titanium tetrachloride and the like can be mentioned.

The concentration of these compound aqueous solutions is also preferably in the range of 0.1 to 15% by weight, more preferably 1.0 to 5.0% by weight as the inorganic oxide.
Subsequently, each aqueous solution is mixed. The mixing ratio is such that the composition in the resulting water gas shift reaction catalyst is in the above range. When mixing each raw material aqueous solution, it is preferable to mix uniformly, stirring moderately. Moreover, you may add an acid and / or an alkali so that the pH of the aqueous solution mixed or the hydrogel to produce | generate may become the range of 5.5-10.5 as needed, and also 6.5-9.0. As the acid and alkali, those that do not hinder the function as a catalyst are desirable. Examples of the acid include nitric acid, sulfuric acid, hydrochloric acid, and organic acids. Examples of the alkali include sodium hydroxide, sodium carbonate, and potassium hydroxide. , Ammonia, amines and the like.

Moreover, it is preferable that the temperature at the time of mixing exists in the range of 5-75 degreeC in general.
Mixing produces a mixed hydrogel of oxides of active metal elements, alkaline earth metal oxides and inorganic oxides.

When the pH falls within the above range, a catalyst having a high specific surface area can be obtained.
When the pH of the produced hydrogel is out of the above range, gelation becomes insufficient, the specific surface area decreases, and the activity may decrease.

  Subsequently, the obtained hydrogel may be aged as necessary. The aging temperature is preferably in the range of 15 to 90 ° C. The aging time varies depending on the temperature, but is generally 10 minutes to 12 hours. When aging is performed under such conditions, the composition of the mixed components is promoted, the growth of particles in the hydrogel can be controlled, and a catalyst having a high specific surface area can be obtained with good reproducibility. It may be either agitated or not at the time of aging.

The resulting hydrogel is then filtered, washed and dried. In addition, after aging, it may filter and wash | clean, and you may disperse | distribute again in solvents, such as water, and may age | cure | ripen.
Washing is not particularly limited as long as the by-produced salt and excess base can be removed, and a conventionally known method can be employed. For example, it can be cleaned using pure water, preferably warm water, or ammonia water.

It is preferable that the washed hydrogel is usually dried at 50 to 130 ° C.
It is desirable that the oxide powder obtained by drying is pulverized when there is an aggregate of about 3 mm or more to obtain a powder of about 1 mm or less. By crushing, the agglomerates do not become hard solids when fired at a high temperature later, can be fired uniformly, and can be easily molded and used for molding. Is obtained.

As a molding method, a known method can be adopted, for example,
・ Method of spray-drying dispersion liquid in which composite oxide powder is dispersed in water ・ Method of filling composite oxide powder directly into a molding container and pressurizing and molding ・ Adding moisture to composite oxide powder, necessary Depending on the method, there may be mentioned a method of adding a molding aid, kneading, pressing from a die to form a pellet cut into an appropriate length, a method of forming a pellet into a spherical shape with a rotary granulator, and the like.

  It is desirable that the obtained complex oxide powder (molded body) is fired in the range of 200 to 900 ° C, more preferably 250 to 750 ° C. By calcining in this range, a highly active catalyst having high water resistance, high surface area can be obtained.

When the firing temperature is low, some of the inorganic oxide, alkaline earth metal oxide and active metal oxide remain as hydroxide, and sufficient activity may not be obtained.
If the firing temperature of the composite oxide powder or molded product is too high, the specific surface area may decrease, and the resulting catalyst may have insufficient activity.

  The water gas shift catalyst thus obtained is reduced during use. In the reduction treatment, after the water gas shift catalyst is filled, the heat treatment is carried out in the range of 150 to 450 ° C., further 200 to 400 ° C. in a reducing gas atmosphere.

As the reducing gas, hydrogen gas is usually used, and at this time, an inert gas such as nitrogen gas can be mixed and used.
When the reduction treatment temperature is less than 150 ° C., the reduction of the active metal oxide is insufficient, and sufficient activity may not be obtained.

When the reduction treatment temperature exceeds 450 ° C., agglomerated metal fine particles may be formed, or metal fine particles having a large particle diameter may be formed, resulting in insufficient activity.
In addition, although reduction processing time changes with reduction processing temperature, 0.5 to 5 hours are preferable normally.

The reduced active metal is in the form of fine particles and is present in the composite oxide powder.
The water gas shift catalyst after the reduction treatment is used for the CO removal reaction so as not to come into contact with outside air or moisture as much as possible.

In addition, the deactivated catalyst can be reduced and used again, or once brought into contact with water, it can be regenerated by calcining and reducing again.
[Example]
Hereinafter, although an example explains, the present invention is not limited by these examples.

[Example 1]
Preparation of water gas shift reaction catalyst (1) 181.7 g of copper (II) nitrate trihydrate and 16.9 g of magnesium nitrate hexahydrate were added to 4333 water.
It melt | dissolved in 3g and was set as the A liquid.

Separately, sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 172
. 2533.3 g of water was added to 8 g, and 32.5 g of sodium hydroxide was further dissolved to prepare a solution B.
Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.

  After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then calcined at 350 ° C. for 1 hour in the air to obtain a composite oxide powder (1) composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder (1) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (1). Prepared.

Activity test Water gas shift reaction catalyst (1) 0.8ml was filled in a stainless steel reaction tube with an inner diameter of 6mm, and the catalyst layer temperature was 250 ° C for 1 hour under the flow of hydrogen-nitrogen mixed gas (H ₂ concentration 10 vol%) Reduced. With respect to the water gas shift catalyst after the reduction treatment, the average particle size of the metal fine particles and the amount per 1 g of the catalyst were determined by the above-described method. These numerical values are shown together in Table 1.

Next, after the catalyst layer temperature was set to 200 ° C., the reaction gas mixture (carbon monoxide 6.7% by volume, carbon dioxide 8.0% by volume, hydrogen 52.0% by volume, water vapor 33.3% by volume) ) Was distributed such that SV = 12,000 h ⁻¹ .

  The product gas in the steady state after about 1 hour was analyzed by gas chromatography, the CO concentration at the outlet of the reaction tube was measured, and the CO conversion was calculated from the CO concentration at the inlet of the reaction tube and the decrease rate of the CO concentration at the outlet. . The results are shown in Table 1.

Similarly, the reaction temperature was 230 ° C. and 250 ° C., and the CO conversion rate was evaluated. The results are also shown in Table 1.
Water resistance test After reduction treatment for 1 hour in the same manner as in the activity test, the catalyst layer temperature was lowered to 110 ° C., and then the reaction mixed gas was supplied to replace the hydrogen-nitrogen mixed gas in the catalyst layer. The supply of the reaction gas mixture was stopped and the front and back of the reaction tube were closed with valves, and then the temperature of the catalyst layer was lowered to room temperature to condense water vapor. Thereafter, while supplying nitrogen gas, drying is performed at 130 ° C. for 4 hours, and then reduction treatment-reaction is performed in the same manner as in the activity test, and the reaction temperature is set to 200.
The CO conversion was evaluated at 0 ° C, 230 ° C, and 250 ° C. The difference in the conversion rate from the one not subjected to the condensation treatment of water vapor is the evaluation of water resistance, and the one having no difference indicates that the water resistance is good.

The results are shown in Table 1.
[Example 2]
Preparation of water gas shift reaction catalyst (2) 91.7 g of copper (II) nitrate trihydrate and 16.9 g of magnesium nitrate hexahydrate were dissolved in 2173.3 g of water, and 56.3 g of 63.5% nitric acid was dissolved. In addition, A solution was obtained.

Separately, a sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 306
. 4493.3 g of water was added to 4 to prepare a B solution.
Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.

  After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then calcined at 350 ° C. for 1 hour in the air to obtain a composite oxide powder (2) composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder (2) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (2). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Example 3]
Preparation of water gas shift reaction catalyst (3) 244.6 g of copper (II) nitrate trihydrate and 16.9 g of magnesium nitrate hexahydrate were added to 5506 water.
. It melt | dissolved in 6g and was set as A liquid.

Separately, sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%)
1160 g of water was added to 1 and 70.9 g of sodium hydroxide was further added and dissolved to prepare a solution B.
Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.

  After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then calcined in the air at 350 ° C. for 1 hour to obtain a composite oxide powder (3) composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder (3) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (3). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Example 4]
Preparation of water gas shift reaction catalyst (4) 183.5 g of copper (II) nitrate trihydrate and 6.5 g of magnesium nitrate hexahydrate were dissolved in 4066.6 g of water to prepare a solution A.

Separately, a sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 177
. 2600 g of water was added to No. 3, and 29.0 g of sodium hydroxide was further added and dissolved to obtain a solution B.

Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then calcined in the air at 350 ° C. for 1 hour to obtain a composite oxide powder (4) composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder (4) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (4). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Example 5]
Preparation of water gas shift reaction catalyst (5) 183.5 g of copper (II) nitrate trihydrate and 37.7 g of magnesium nitrate hexahydrate were dissolved in 4386.6 g of water to prepare solution A.

Separately, sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 155
. 2280 g of water was added to No. 5, and 42.8 g of sodium hydroxide was further added to dissolve it.

Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then fired at 350 ° C. for 1 hour in the air to obtain a composite oxide powder (5) composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder (5) is filled into a tablet molding machine, press-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (5). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Example 6]
Preparation of water gas shift reaction catalyst (6) 183.4 g of cobalt (II) nitrate hexahydrate and 16.9 g of magnesium nitrate hexahydrate were dissolved in 4040 g of water to prepare solution A.

Separately, a sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 179
. 2626.7 g of water was added to 1, and 31.1 g of sodium hydroxide was further added to dissolve it to prepare a liquid B.

Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then fired at 350 ° C. for 1 hour in the air to obtain a composite oxide powder (6) composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder (6) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (6). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Example 7]
Preparation of water gas shift reaction catalyst (7) 182.3 g of copper (II) nitrate trihydrate and 15.3 g of calcium nitrate tetrahydrate were dissolved in 4146.7 g of water to prepare a solution A.

Separately, a sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 171
. 2520 g of water was added to 8 g, and 32.7 g of sodium hydroxide was further dissolved to prepare a solution B.
Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.

  After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then calcined in the air at 350 ° C. for 1 hour to obtain a composite oxide powder (7) composed of cobalt oxide, magnesium oxide and alumina.

Next, the composite oxide powder (7) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (7). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Example 8]
Preparation of water gas shift reaction catalyst (8) 182.3 g of copper (II) nitrate trihydrate, 16.9 g of magnesium nitrate hexahydrate and 219.1 g of zirconium nitrate dihydrate were dissolved in 6733.3 g of water. It was set as A liquid.

Separately, 91.1 g of sodium hydroxide was dissolved in 728.9 g of water to obtain solution B.
Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then fired at 350 ° C. for 1 hour in the air to obtain a composite oxide powder (8) composed of cobalt oxide, magnesium oxide and zirconium oxide. .

Next, the composite oxide powder (8) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (8). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Example 9]
Preparation of water gas shift reaction catalyst (9) 116.2 g of copper (II) nitrate trihydrate, 63.3 g of cobalt (II) nitrate hexahydrate and 16.9 g of magnesium nitrate hexahydrate were dissolved in 4040 g of water. It was set as A liquid.

Separately, a sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 179
. 2626.7 g of water was added to 1 g, and 31.0 g of sodium hydroxide was further dissolved to prepare a solution B.

Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel is dried at 120 ° C. for one day and then calcined at 350 ° C. for 1 hour in the air to obtain a composite oxide powder comprising copper oxide, cobalt oxide, magnesium oxide and aluminum oxide (9) Got.

Next, the composite oxide powder (9) is filled into a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size is adjusted to 20 to 42 mesh to adjust the water gas shift reaction catalyst (9). Prepared.

The obtained catalyst was evaluated in the same manner as in Example 1.
The results are shown in Table 1.
[Comparative Example 1]
Preparation of catalyst sample 183.5 g of copper (II) nitrate trihydrate was dissolved in 4000 g of water to prepare solution A.

Separately, a sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9% by weight) 181.
2666.7 g of water was added to No. 9, and 26.1 g of sodium hydroxide was further added and dissolved to obtain a B solution.

Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then fired at 350 ° C. for 1 hour in the air to obtain a composite oxide powder composed of copper oxide and alumina.

Next, the composite oxide powder was filled in a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size was adjusted to 20 to 42 mesh to prepare a sample for catalyst comparison.
The obtained catalyst was evaluated in the same manner as in Example 1.

The results are shown in Table 1.
[Comparative Example 2]
Preparation of catalyst sample 183.5 g of copper (II) nitrate trihydrate and 207.8 g of magnesium nitrate hexahydrate were added to water 613
It melt | dissolved in 3.3 g and was set as A liquid.

Separately, sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%)
Water 333.3g was added to 4, and sodium hydroxide 118.7g was further added and melt | dissolved, and it was set as B liquid.

Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then fired at 350 ° C. for 1 hour in the air to obtain a composite oxide powder composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder was filled in a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size was adjusted to 20 to 42 mesh to prepare a sample for catalyst comparison.
The obtained catalyst was evaluated in the same manner as in Example 1.

The results are shown in Table 1.
[Comparative Example 3]
Preparation of catalyst sample 281.3 g of copper (II) nitrate trihydrate and 16.9 g of magnesium nitrate hexahydrate were added to 5306 water
. It melt | dissolved in 7g and was set as A liquid.

Separately, sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%)
1360 g of water was added to 5 g, and further 93.6 g of sodium hydroxide was added and dissolved to obtain B solution.

Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.
After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then fired at 350 ° C. for 1 hour in the air to obtain a composite oxide powder composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder was filled in a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size was adjusted to 20 to 42 mesh to prepare a sample for catalyst comparison.
The obtained catalyst was evaluated in the same manner as in Example 1.

The results are shown in Table 1.
[Comparative Example 4]
Preparation of sample for comparison with catalyst 45.9 g of copper (II) nitrate trihydrate and 16.9 g of magnesium nitrate hexahydrate were added to water 6133.
It melt | dissolved in 3g, and also 63.5% nitric acid 126.5g was added and it was set as A liquid.

Separately, sodium aluminate aqueous solution (concentration as Al ₂ O ₃ : 38.9 wt%) 375
. 5506.7g of water was added to 5, and it was set as B liquid.
Next, liquid B was heated to 50 ° C., and liquid A was added with stirring to prepare a hydrogel.

  After this hydrogel slurry was aged by stirring at 50 ° C. for 30 minutes, the gel was filtered and thoroughly washed with warm water. The washed gel was dried at 120 ° C. for one day and then fired at 350 ° C. for 1 hour in the air to obtain a composite oxide powder composed of copper oxide, magnesium oxide and alumina.

Next, the composite oxide powder was filled in a tablet molding machine, pressure-molded at 50 kg / cm ² , then pulverized, and the particle size was adjusted to 20 to 42 mesh to prepare a sample for catalyst comparison.
The obtained catalyst was evaluated in the same manner as in Example 1.

  The results are shown in Table 1.

Claims (4)

(i) one or more elements selected from Cu and Co; (ii) one or more alkaline earth metal oxides selected from magnesia and calcia (CaO); and (iii) the balance selected from alumina and zirconia. One or more inorganic oxides,
In the range content is 40 to 80% by weight in terms of oxide of the element (i), water gas shift, wherein the content of the alkaline earth metal oxide (ii) is 1-10 wt% Reaction catalyst.   The molar ratio (Mae) / (Mam) between the number of moles of the alkaline earth metal oxide (Mae) and the number of moles of the oxide of the element (Mam) is in the range of 0.01 to 0.2. The water gas shift reaction catalyst according to claim 1, wherein the catalyst is a water gas shift reaction catalyst.   The water gas shift reaction catalyst according to claim 1 or 2, wherein the alkaline earth metal oxide is magnesia.   The water gas shift reaction catalyst according to any one of claims 1 to 3, wherein the inorganic oxide is alumina.