JP2001079398A - Methanol synthesis and cracking catalyst, its production and methanol synthesis and cracking method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a methanol synthesis catalyst having a high catalytic activity and high methanol selectivity even under a low pressure and a methanol cracking catalyst excellent in selectivity to crack methanol into carbon monoxide and hydrogen by carrying palladium on a carrier composed of a mesoporous compound. SOLUTION: The mesoporous compound used as a carrier is a porous body usually having about 2-50 nm center fine pore diameter and preferably having fine pores about 3-10 nm in diameter. As the mesoporous compound, for example, a compound containing the oxide of zirconium, cerium, titanium, silicon or the like. The average particle diameter of the carried palladium is usually about <=10 nm, preferably about <=3 nm as a measured value by the XDR method or the hydrogen adsorption method. Palladium is desirably highly dispersed to be carried on the carrier. The carrying quantity of palladium is usually about 0.5-15 wt.% per total sum of palladium and the mesoporous compound carrier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a catalyst for methanol synthesis, a method for synthesizing methanol using the catalyst, a catalyst for methanol decomposition, and a method for methanol decomposition using the catalyst.

[0002]

2. Description of the Related Art As a method for synthesizing methanol from synthesis gas, a gas phase reaction process performed in Germany in 1923 at 20 MPa and 400 ° C. in the presence of a zinc-chromium-based catalyst has been proposed.
Industrialized.

[0003] In 1959, a copper-zinc catalyst was developed in the UK, and in 1966, a methanol synthesis method at a reaction pressure of 5 MPa was industrialized. After that, the improvement of copper-zinc catalyst and the improvement of the reaction process proceeded.
Industrial methanol synthesis became possible at 1010 MPa and a reaction temperature of 250 to 300 ° C., but in practice, the reaction outlet concentration of methanol was increased, and equipment costs and operation costs became advantageous. It is carried out under the condition of 1010 MPa.

[0004] However, in order to maintain a high reaction pressure, a boosting power is required, so that it is necessary to perform the reaction at a lower pressure in order to reduce operating costs. For example, when performing methanol synthesis using a raw material gas having a composition of 33 vol% of carbon monoxide and 67 vol% of hydrogen at 2 MPa and 250 ° C. using a copper-zinc catalyst, the equilibrium conversion of methanol is 21%. It is not practical.

Under the same conditions, when the reaction temperature is set at 200 ° C., an equilibrium conversion of 60% can be theoretically achieved. Since a catalyst is required, the utility is also poor.

[0006] Catalysts for methanol synthesis other than copper-zinc catalysts have also been developed. For example, a palladium-based catalyst prepared by an impregnation method using a rare earth oxide as a carrier has been reported (Journal of the Chemical Society Chemical Comm.
unications, 1982, Issue 12, p. 645).

[0007] However, this catalyst has a problem that the reaction activity is low and the methanol selectivity is low.

Thus, at lower reaction pressures,
There is a strong need for the development of a catalyst that can efficiently synthesize methanol.

On the other hand, a methanol decomposition reaction is a reverse reaction of a methanol synthesis reaction from carbon monoxide and hydrogen, and is an endothermic reaction. Therefore, if the reaction proceeds with low-temperature exhaust heat of 200 ° C. or less as a heat source, energy recovery of low-temperature exhaust heat becomes possible.

In order to put this into practical use, a catalyst for decomposing methanol having high catalytic activity even at 200 ° C. or lower and having high selectivity to carbon monoxide and hydrogen is required.

However, at present, no suitable catalyst has been found.

[0012]

An object of the present invention is to provide a catalyst for methanol synthesis having excellent catalytic activity even at low pressure and having high methanol selectivity, and a method for synthesizing methanol using the catalyst. Aim. It is another object of the present invention to provide a methanol decomposition catalyst having excellent catalytic activity even at low temperatures and excellent in selectivity to carbon monoxide and hydrogen, and a methanol decomposition method using the catalyst.

[0013]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a catalyst comprising palladium on a support comprising a mesoporous compound has high catalytic activity and high selectivity for methanol synthesis reaction and methanol decomposition reaction. And completed the present invention.

That is, the present invention provides the following methanol synthesis /
The present invention relates to a decomposition catalyst and a methanol synthesis / decomposition method. 1. A catalyst for methanol synthesis in which palladium is supported on a support made of a mesoporous compound. 2. 2. The catalyst for methanol synthesis according to the above 1, wherein the mesoporous compound has a center pore diameter of 2 to 50 nm. 3. A method for producing a catalyst for methanol synthesis, comprising: (1) a step of depositing palladium hydroxide on a mesoporous compound to obtain a catalyst precursor; and (2) heating the obtained catalyst precursor.
A method for producing a catalyst, comprising: a step of oxidizing palladium hydroxide; and (3) a step of subjecting the oxidized catalyst precursor to a reduction treatment. 4. A method for synthesizing methanol by reacting carbon monoxide and / or carbon dioxide with hydrogen in the gas phase, wherein the reaction is carried out in the presence of a catalyst supporting palladium on a support composed of a mesoporous compound. A method for synthesizing methanol. 5. The method for synthesizing methanol according to the above item 4, wherein the reaction pressure is 1 to 15 MPa. 6. The method for synthesizing methanol according to any one of the above items 4 to 5, wherein the reaction temperature is 150 to 300 ° C. 7. A catalyst for methanol decomposition in which palladium is supported on a support made of a mesoporous compound. 8. 8. The catalyst for decomposing methanol according to 7 above, wherein the mesoporous compound has a pore diameter of 2 to 50 nm. 9. A method for producing a catalyst for decomposing methanol, comprising: (1) a step of depositing palladium hydroxide on a mesoporous compound to obtain a catalyst precursor; and (2) heating the obtained catalyst precursor.
A method for producing a catalyst, comprising: a step of oxidizing palladium hydroxide; and (3) a step of subjecting the oxidized catalyst precursor to a reduction treatment. 10. A gas phase decomposition method for decomposing methanol into carbon monoxide and hydrogen, wherein the reaction is carried out in the presence of a catalyst in which palladium is supported on a support made of a mesoporous compound. 11. The method for decomposing methanol according to the above item 10, wherein the reaction pressure is 0.05 to 1 MPa. 12. 12. The method for decomposing methanol according to any of the above 10 to 11, wherein the reaction temperature is 130 to 350 ° C.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The first invention of the present invention relates to a catalyst for methanol synthesis in which palladium is supported on a support comprising a mesoporous compound.

The second invention of the present invention relates to a catalyst for decomposing methanol in which palladium is supported on a support comprising a mesoporous compound.

Hereinafter, the catalyst according to the first invention and the catalyst according to the second invention may be collectively referred to as "catalyst of the present invention".

In the catalyst of the present invention, the mesoporous compound (mesoporous body) used as a carrier usually has a center pore diameter.
About 2 to 50 nm, preferably about 2 to 20 nm, particularly preferably
It is a porous body having pores of about 3 to 10 nm. The mesoporous compound used in the present invention preferably has an almost uniform regular pore structure constituted by one-dimensional pores. One-dimensional pores indicate a state in which cylindrical thin tubes are aligned in the same direction and are further stacked. One example of such a structure is schematically shown in FIG. It is particularly preferable that the mesoporous compound has most of its pores, for example, about 90% or more of pores having a pore diameter of 4 to 6 nm. As the value of the center pore diameter, a value measured by a nitrogen adsorption method is used.

Examples of the mesoporous compound include compounds containing oxides such as zirconium, cerium, titanium and silicon, and compounds containing two or more kinds of these oxides. The mesoporous compound can be produced using a known method. For example, a method for producing a mesoporous compound containing cerium oxide is described in Journa.
l of Catalysis, 178, 299-308 (1998), etc.
A method for producing a mesoporous compound containing zirconium oxide is described in Journal of Material Chemistry, Volume 6, pages 89 to 95 (1.
996), and the method for producing a mesoporous compound containing titanium oxide is described in Chemical Materials, Volume 9, pages 2690 to 2693.
(1997), a method for producing a mesoporous compound containing silicon oxide is described in Catalyst, Vol. 37, No. 8, pp. 636-641 (1995).
And so on.

The average particle size of palladium supported on the catalyst of the present invention is not particularly limited as long as a predetermined effect can be obtained. The average particle size of palladium is usually about 10 nm or less, preferably about 3 nm or less, as measured by the XRD method or the hydrogen adsorption method.

In the catalyst of the present invention, it is desirable that palladium be highly dispersed and supported on the carrier.

The supported amount of palladium in the catalyst of the present invention is usually about 0.5 to 15% by weight, preferably about 2 to 10% by weight, based on the total amount of the palladium and the mesoporous compound carrier. If the amount of supported palladium is too small, sufficient catalytic activity will not be exhibited.

The shape of the catalyst of the present invention is not particularly limited, and examples thereof include powder, granules, and strips. The particle size of the catalyst is not particularly limited as long as a predetermined effect is obtained, but is usually about 10 to 100 mesh, preferably 30 mesh.
It is about 80 mesh. The catalyst may be produced using a carrier having a desired particle size, or may be pulverized to a desired particle size after supporting palladium on the carrier.
The former is preferred.

The catalyst of the present invention may be used after being formed into pellets, cylinders, honeycombs, or the like. The molding method is
A method known per se can be used, for example, a method of mixing and molding with a known binder that does not adversely affect the reaction (e.g., silica gel or the like), a known binder that does not adversely affect the reaction (e.g., silica gel or the like) A method of applying a mixture of the above to a substrate such as ceramics.

By using such a shaped catalyst,
While promoting the diffusion of the reactants, the activity of the catalyst can be appropriately controlled.

The catalyst of the present invention (first invention and second invention) can be produced, for example, by a production method having the following steps (hereinafter sometimes referred to as “precipitation precipitation method”). (1) a step of depositing palladium hydroxide on a support composed of a mesoporous compound to obtain a catalyst precursor; (2) a step of heating the obtained catalyst precursor to oxidize palladium hydroxide; and (3) oxidation. A step of subjecting the catalyst precursor thus subjected to reduction treatment to reduce palladium oxide in the catalyst precursor to metal palladium.

Step (1) is a step of precipitating palladium hydroxide on a support comprising a mesoporous compound.

In the step (1), palladium hydroxide is precipitated on the mesoporous compound by, for example, a method of impregnating the mesoporous compound into a palladium compound solution under a condition of about pH 3 to 8, and a catalyst precursor (hereinafter, referred to as “the catalyst precursor”). A precursor).

The palladium compound used in step (1) is not particularly limited as long as it is a compound that dissociates Pd ^{2+ in} a solution. Such compounds include, for example, palladium salts such as palladium chloride, palladium nitrate and palladium acetate. These compounds may be used alone or in a combination of two or more.

The palladium solution used in the step (1) can be prepared by dissolving a palladium compound in a solvent such as water, methanol, acetone or a mixed solvent thereof. Of these, water is preferred. The concentration of the palladium solution can be appropriately set according to the type of the palladium compound to be used and the like, but is usually 0.1 to 5
mol / l, preferably about 0.5 to 2 mol / l.

The pH can be adjusted by, for example, adding a basic compound such as sodium carbonate or potassium carbonate.

In order to efficiently disperse the palladium solution in the pores of the mesoporous compound, palladium hydroxide may be precipitated in the pores of the mesoporous compound while shaking by ultrasonic waves.

The deposited palladium hydroxide may be aged for about 0.5 to 24 hours, if necessary. The temperature for aging is not particularly limited, but is usually about 50 to 90 ° C.

The obtained precursor is isolated by a known method such as filtration. The obtained precursor may be washed or dried as necessary.

In step (2), the precursor obtained in step (1) is heated to oxidize the supported palladium hydroxide.

The heating is performed in an oxidizing atmosphere such as air. The heating temperature is not particularly limited, but is usually 200 to 500.
It is about ° C. The heating time is not particularly limited, but is usually
It is about 0.5 to 10 hours.

In step (3), the precursor obtained in step (2) is subjected to a reduction treatment to reduce the supported palladium oxide to metal palladium. Step (3) is a step
The reaction may be performed immediately after (2) is performed, or may be performed immediately before the reaction, for example, after installing a catalyst in the reactor.

Examples of the reduction treatment performed in the step (3) include a gas phase reduction treatment in a reducing gas atmosphere such as hydrogen, a liquid phase reduction treatment using a reducing agent solution such as a formalin solution, and the like. Specific examples of the hydrogen reduction treatment include a method of heating the catalyst at about 200 to 500 ° C. for about 3 to 10 hours in a hydrogen atmosphere.

[0039] The catalyst of the present invention can be regenerated by performing a hydrogen reduction treatment or the like, as needed, after once using it.

The catalyst produced by the above method is different from the impregnation method in which a palladium salt is attached to the surface of a carrier and then calcined in the air to form a palladium oxide. Thus, palladium is supported by being precipitated in the pores thereof, so that palladium can be highly dispersed and supported in the pores of the mesoporous compound, and the palladium obtained has a large specific surface area.

The smaller the content of palladium, the higher the degree of dispersion of palladium, so that the catalytic activity per palladium can be increased.

The catalyst according to the first invention comprises carbon monoxide and
In a method of synthesizing methanol by reacting carbon dioxide and hydrogen in the gas phase, for example, the catalyst exhibits catalytic activity under the following reaction conditions.

The reaction pressure is not particularly limited, but is usually 1
The pressure is about 15 MPa, preferably about 1.2 to 10 MPa, and more preferably 1.5 to 5 MPa. The reaction pressure is approximately equal to the partial pressure of the reactants. If the reaction pressure is too low, the methanol yield will decrease.

The reaction temperature is not particularly limited, but is usually 15
The temperature is about 0 to 300 ° C, preferably about 170 to 250 ° C. If the reaction temperature is too low, the catalytic activity will decrease. If the reaction temperature is too high, the chemical equilibrium is restricted, and sufficient reaction efficiency cannot be obtained unless the reaction pressure is increased.

The composition ratio of the reaction raw materials is not particularly limited, but should be determined in consideration of the stoichiometric relationship of the reaction. The composition ratio of carbon monoxide and / or carbon dioxide to hydrogen is usually about 1 to 5, preferably about 2 to 4, as H ₂ / (CO ₂ + CO) (molar ratio). Carbon monoxide and carbon dioxide may be used alone or in combination.

The reaction raw materials may be diluted with a reaction inert gas such as nitrogen as long as the reaction is not adversely affected. If the dilution is excessive, energy loss occurs when the pressure is increased to the reaction pressure.

The reaction raw materials of carbon monoxide and / or carbon dioxide and hydrogen may be supplied in a gas phase flow system.
The supply amount of the reaction raw material can be appropriately selected depending on the size, shape, reaction temperature, reaction pressure, and the like of the reactor, but is usually about 500 to 10,000 ml / h ^-1 per 1 g of the catalyst, preferably 1,000 to 1,000. It is about 5000 ml · h ^-1 .

The catalyst according to the second invention exhibits catalytic activity under the following reaction conditions in a method in which methanol is reacted in the gas phase to decompose into carbon monoxide and hydrogen.

The reaction temperature is usually about 130-350 ° C., preferably about 150-300 ° C. If the reaction temperature is too low, the decomposition efficiency of methanol decreases, whereas if the reaction temperature is too high, the selectivity of methanol to dehydrogenation products may decrease due to by-product methane.

The reaction pressure is usually about 0.05-1 MPa, preferably about 0.1-0.5 MPa. If the reaction pressure is too high, a high reaction conversion cannot be obtained due to chemical equilibrium, and if the reaction pressure is too low, the yield of decomposition products will decrease. The methanol partial pressure is usually about 0.01 to 1 MPa, preferably 0.02 to 0.
It is about 5MPa.

The method of supplying methanol is not particularly limited, but it is usually supplied in gaseous form using a gas phase flow system or the like. Methanol is a gas that does not adversely affect the reaction,
For example, it may be supplied after being diluted with helium, nitrogen, argon, or the like.

The amount of methanol to be supplied may be appropriately selected according to the size and shape of the reactor and the reaction temperature, and is usually about 0.1 to 10 mol · h ⁻¹ per 1 g of the catalyst.

[0053]

The catalyst according to the present invention can be used in a methanol synthesis reaction at a lower temperature and a lower pressure compared to a known catalyst in which palladium is supported on an ordinary oxide carrier.
Shows good catalytic activity.

In the catalyst of the present invention, it is considered that the structure of the mesoporous compound contributes to the synthesis of methanol, and the interaction between the carrier and palladium enhances the catalytic activity at low temperature and low pressure.

Further, the catalyst according to the present invention exhibits good catalytic activity and high selectivity to carbon monoxide under low temperature and low pressure conditions in the dehydrogenation decomposition reaction of methanol, as compared with known catalytic reactions. The methanol decomposition reaction can be performed at a favorable rate.

Also in this case, it is considered that the structure of the mesoporous compound contributes to the decomposition of methanol and enhances the reaction activity of palladium.

[0057]

Embodiments of the present invention will be described below. The present invention is not limited to these examples.

Example 1 A mesoporous compound composed of cerium oxide was used in the Journal of Japan.
Catalysis, vol. 178, pp. 299-308 (1998). The center pore diameter of the obtained mesoporous compound was 4 nm as measured by a nitrogen adsorption method, and the maximum pore diameter was 10 nm. The particle size of the mesoporous compound is about 60
It was a mesh. Palladium was supported on this compound by a precipitation method to obtain a desired palladium catalyst. This precipitation method is as follows.

0.26 g of palladium chloride (PdCl ₂ ) was weighed,
This was dissolved in 300 ml of distilled water. The solution was impregnated with 5 g of the above mesoporous compound, and a 1N solution of sodium carbonate was added to adjust the pH to 10 or less, and palladium hydroxide was supported on the carrier. After that, calcination was performed at 500 ° C. for 5 hours through each process of stirring aging (2 hours), washing with water, and drying.

The supported amount of palladium in the obtained palladium-mesoporous compound catalyst was 3% by weight.

Example 2 A mesoporous compound comprising zirconium oxide was used
Synthesized by the method described in l of Material Chemistry, vol. 6, pages 89-95 (1996). The center pore diameter of the obtained mesoporous compound was 5 nm as measured by a nitrogen adsorption method, and the maximum pore diameter was 10 nm. The particle size of the mesoporous compound was about 60 mesh. Palladium was supported on this compound by a precipitation method to obtain a palladium catalyst.
This precipitation method is as follows.

0.26 g of palladium chloride (PdCl ₂ ) was weighed and dissolved in 300 ml of distilled water. This solution was impregnated with 5 g of the above mesoporous compound, and a 1N solution of sodium carbonate was added thereto while shaking with ultrasonic waves to adjust the pH to 10%.
In the following, palladium hydroxide was supported on the carrier. After that, after each process of stirring and aging (2 hours), washing and drying, 5
Baking was performed at 00 ° C. for 5 hours.

The supported amount of palladium in the obtained palladium-mesoporous compound catalyst was 3% by weight.

Example 3 A mesoporous compound composed of titanium oxide was used as a chemical.
Materials, vol. 9, pages 2690 to 2693 (1997). The center pore diameter of the obtained mesoporous compound was 3 nm as measured by a nitrogen adsorption method, and the maximum pore diameter was 10 nm. The particle size of the mesoporous compound is about 50
It was a mesh. A palladium catalyst in which palladium was supported on this compound by a precipitation method was obtained. This precipitation method is as follows.

0.26 g of palladium chloride (PdCl ₂ ) was weighed and dissolved in 300 ml of distilled water. 5 g of the above mesoporous compound was mixed into this solution, and a 1N solution of sodium carbonate was added to adjust the pH to 10 or less, and palladium hydroxide was supported on a carrier. After that, calcination was performed at 500 ° C. for 5 hours through each process of stirring aging (2 hours), washing with water, and drying.

The supported amount of palladium in the obtained palladium-mesoporous compound catalyst was 3% by weight.

Example 4 The catalyst obtained in Example 1 was incorporated into a fixed bed flow type reactor, and the catalyst was subjected to a hydrogen reduction treatment (300 ° C., 1 hour). A reaction gas consisting of one volume of carbon monoxide was supplied at a pressure of 2 MPa and a space velocity of 3600 ml · h ⁻¹ · g ⁻¹ , and a methanol synthesis reaction was performed at a reaction pressure of 2 MPa.

As a result, the amount of methanol produced per gram of the catalyst was 4.0 mmol · h ⁻¹ , and the methanol selectivity was 97.7%. The main by-product was methane.

Example 5 Using the catalyst obtained in Example 2, a methanol synthesis reaction was carried out in the same manner as in Example 4 except that the reaction temperature was changed to 250 ° C.

As a result, the amount of methanol produced per gram of the catalyst was 6.3 mmol · h ⁻¹ , and the methanol selectivity was 96.2%.

Example 6 Using the catalyst obtained in Example 3, a methanol synthesis reaction was carried out in the same manner as in Example 4.

As a result, the amount of methanol produced per gram of the catalyst was 3.1 mmol · h ⁻¹ , and the methanol selectivity was 91.5%.

Example 7 The catalyst obtained in Example 1 was incorporated in a fixed bed flow reactor, and the catalyst was subjected to a hydrogen reduction treatment (300 ° C., 1 hour). A reaction gas consisting of one volume of carbon dioxide was supplied at a pressure of 2 MPa and a space velocity of 3600 ml · h ⁻¹ · g ⁻¹ to perform a methanol synthesis reaction at a reaction pressure of 2 MPa.

As a result, the amount of methanol produced per 1 g of the catalyst was 3.5 mmol · h ⁻¹ , and the methanol selectivity was 63%. The major by-product was carbon monoxide. By-produced carbon monoxide is separated and recovered together with the unreacted reaction gas, and is added to the raw material, whereby it can be recycled and recycled to synthesize methanol.

Example 8 The catalyst obtained in Example 1 was incorporated in a fixed-bed flow reactor, and the catalyst was subjected to a hydrogen reduction treatment, and then methanol diluted with argon (methanol partial pressure: 0.02MP)
a, a reaction pressure of 0.1 MPa and a space velocity of 25000 ml · h ⁻¹ · g ⁻¹ ) were supplied, and a methanol decomposition reaction was carried out at a reaction temperature of 160 ° C.

As a result, the steady decomposition activity per gram of the catalyst was 30 mmol · h ⁻¹ , and the selectivity to carbon monoxide was 100%.

Example 9 The catalyst obtained in Example 2 was incorporated in a fixed bed flow type reactor, and the catalyst was subjected to a hydrogen reduction treatment, and then methanol diluted with argon (methanol partial pressure: 0.02MP)
a, a reaction pressure of 1 MPa) and a space velocity of 25000 ml · h ⁻¹ · g ⁻¹ ) were supplied, and a methanol decomposition reaction was performed at a reaction temperature of 180 ° C.

As a result, the steady decomposition activity per gram of the catalyst was 52 m
mol · h ⁻¹ and the selectivity to carbon monoxide was 100%.

Example 10 The catalyst obtained in Example 3 was incorporated in a fixed-bed flow reactor, and the catalyst was subjected to a hydrogen reduction treatment. Then, methanol diluted with argon (methanol partial pressure: 0.02 MPa) was added thereto.
a, a reaction pressure of 0.1 MPa) and a space velocity of 25000 ml · h ⁻¹ · g ⁻¹ ) were supplied to carry out a methanol decomposition reaction at a reaction temperature of 160 ° C.

As a result, the steady decomposition activity per gram of the catalyst was 41 m
mol · h ⁻¹ and the selectivity to carbon monoxide was 100%.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating a part of a mesoporous compound having one-dimensional pores.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (Reference) C07C 31/04 C07C 31/04 F term (Reference) 4G040 EA02 EB16 EB23 EC03 EC08 4G069 AA03 AA08 AA12 AA14 BA04B BA05B BB04B BB05A BB05A BC43A BC50B BC51A BC72A EA02Y EA06 EA18 EB18Y EC10X FA02 FA08 FB08 FB30 FB34 FB39 FB43 FC06 FC07 4H006 AA02 AC41 BA25 BA56 BA81 BC10 BC11 BC13 BE20 BE40 BE41

Claims (12)

[Claims] 1. A catalyst for methanol synthesis in which palladium is supported on a support comprising a mesoporous compound. 2. A mesoporous compound having a center pore diameter of 2 to 50 n.
The catalyst for methanol synthesis according to claim 1, wherein m is m. 3. A method for producing a catalyst for methanol synthesis, comprising: (1) a step of depositing palladium hydroxide on a mesoporous compound to obtain a catalyst precursor; and (2) heating the obtained catalyst precursor to obtain water. Oxidizing palladium oxide, and (3)
A method for producing a catalyst, comprising a step of subjecting an oxidized catalyst precursor to a reduction treatment. 4. A method for synthesizing methanol by reacting carbon monoxide and / or carbon dioxide with hydrogen in a gaseous phase, wherein the reaction is carried out on a support comprising a mesoporous compound in the presence of a catalyst carrying palladium. A method for synthesizing methanol, comprising: 5. The method for synthesizing methanol according to claim 4, wherein the reaction pressure is 1 to 15 MPa. 6. The reaction temperature according to claim 4, wherein the reaction temperature is 150 to 300 ° C.
The method for synthesizing methanol according to any one of the above. 7. A catalyst for methanol decomposition in which palladium is supported on a support comprising a mesoporous compound. 8. The catalyst for methanol decomposition according to claim 7, wherein the mesoporous compound has a pore size of 2 to 50 nm. 9. A method for producing a catalyst for decomposing methanol, comprising: (1) a step of depositing palladium hydroxide on a mesoporous compound to obtain a catalyst precursor; and (2) heating the obtained catalyst precursor to obtain Oxidizing palladium oxide, and
(3) A method for producing a catalyst, comprising a step of subjecting the oxidized catalyst precursor to a reduction treatment. 10. A process for decomposing methanol into carbon monoxide and hydrogen, wherein the reaction is carried out in the presence of a catalyst comprising palladium supported on a support comprising a mesoporous compound. . 11. The reaction pressure according to claim 10, wherein the reaction pressure is 0.05 to 1 MPa.
4. The method for decomposing methanol according to 1. 12. The method according to claim 10, wherein the reaction temperature is 130 to 350 ° C.
12. The method for decomposing methanol according to any one of items 11 to 11.