JPH09290158A - Catalyst for producing methanol, its production, and production of methanol using the catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a catalyst with high activation at low temperature by preparing the catalyst for producing methanol from reduced copper containing lanthanoid oxide, in which lanthanoid oxide is mixed with copper particles, which is obtained by heat-treating copper oxide containing a lanthanoid compound in inert gas and reducing the heat-treated copper oxide. SOLUTION: A catalyst used in the production of methanol from carbon monoxide and/or carbon dioxide and hydrogen is prepared from reduced copper containing lanthanoid oxide, in which lanthanoid oxide is mixed with copper particles not exceeding 180 angstrom in diameter, which is obtained by heat- treated copper oxide containing a lanthanoid compound in inert gas and reducing the heat treated copper oxide. A preferable copper oxide containing a lanthanoid compound is expressed by a general formula of (Mx Cuy )7 O2 Aw where M is lanthanoid atom including Dy, Ho, Er, Tb, Tm, Yb, and Lu; A is NO3 group and/or halogen atom.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to carbon monoxide and / or
Alternatively, the present invention relates to a catalyst for producing methanol from carbon dioxide and hydrogen, a method for producing the same, and a method for producing methanol using the catalyst. Methanol is a very useful compound that is widely used as a raw material for the synthesis of formalin or the like, or as a solvent or fuel.

[0002]

2. Description of the Related Art Methanol is produced by a gas phase method represented by Lurgi method and ICI method using synthesis gas as a raw material, and CuO-ZnO-M ₂ O ₃ as a catalyst.
It is carried out mainly using a system catalyst (M = Al, Cr, etc.). As an improved version of this catalyst, for example, C
uO-ZnO-M ₂ O ₃ catalyst (M = Al or Cr) to those obtained by adding a phosphorus compound (JP 59-19546 JP), Al in the CuO-ZnO catalyst, Cr, V, among Mg and Mn One containing one oxide selected from the above (JP-A-57-130547) and one containing a CuO-ZnO catalyst with an alkali (JP-A-60-190232).
No.), CuO-ZnO with controlled structure such as pore size
-M ₂ O ₃ catalyst (M = Al or Cr) (JP-59-2
No. 22232) is also known.

However, such CuO--ZnO
The -M ₂ O ₃ -based catalyst (M = Al, Cr, etc.) acts as a catalyst for the water gas shift reaction regardless of its reduction method or usage form (Catalyst Today, 23 (1)
995) 29-42, and Appl. Catal. A:
General, 112 (1994) 57-73), because it also induces a Boudouard reaction (App.
l. Catal. A: General, 112 (199
4) 57-73), in a methanol synthesis reaction using this catalyst, an interconversion reaction between carbon monoxide and carbon dioxide supplied as a raw material always occurs simultaneously. for that reason,
The amount of methanol produced and the selectivity are strongly influenced by these reactions and, in most cases, are significantly lower than the equilibrium composition values. _{Further, CuO-ZnO-M 2 O} 3 catalyst (M = A
1, Cr, etc.), there is also a problem that the production of methanol is suppressed when the carbon dioxide concentration in the reaction system exceeds a certain level (about 5 to 20 mol%) (Stud. Su.
rf. Sci. Catal. , 64 (1991) 272
-274). Therefore, with the CuO-ZnO-M ₂ O ₃ -based catalyst (M = Al, Cr, etc.), a catalyst having a high activity and selectivity, which allows the methanol synthesis reaction to proceed preferentially over the above-described side reaction. Need to develop.

Further, in the production of methanol, the above-mentioned methanol synthesis reaction is an exothermic reaction, and there is a problem that thermal control of the reactor including removal of reaction heat becomes an obstacle in process design. In addition to the process based on the phase method, a process based on the liquid phase method has been tried (Japanese Patent Laid-Open No. 2-
6420).

In the liquid phase method, since the synthesis gas is introduced into the solvent in which the catalyst is suspended to carry out the reaction, thermal control becomes relatively easy, and the methanol production can be performed at a higher conversion rate than the gas phase method. It can be carried out. However, also in this liquid phase method, since a CuO—ZnO—M ₂ O ₃ based catalyst (M = Al, Cr, etc.) is used as in the gas phase method, the amount of methanol produced by the side reaction as described above. And the problem of reduced selectivity still exists. in this way,
In the conventional method for producing methanol, both in the gas phase method and the liquid phase method, there is a problem that the production amount and selectivity of methanol are lowered due to side reactions that occur concurrently.

On the other hand, a lanthanoid compound-containing copper oxide represented by the general formula (M _x Cu _y ) ₇ O _z A _w (in the formula, M is a group consisting of Dy, Ho, Er, Tb, Tm, Yb and Lu). Represents at least one lanthanoid atom selected from, A represents a halogen atom and / or a NO ₃ group, and x +
y = 1, 0 <x / y ≦ 10, 6 ≦ z ≦ 8, 0.5 ≦ w ≦
A method for producing methanol using lanthanoid oxide-containing reduced copper containing a mixture of lanthanoid oxide and reduced copper, which is obtained by subjecting lanthanoid oxide to reduced copper, is also known (JP-A-6-340419). ), And catalysts that exhibit even higher activity and selectivity are desired.

[0007]

In view of the above technical background, the present invention provides a highly active catalyst for producing methanol (that is, a catalyst for producing methanol from carbon monoxide and / or carbon dioxide and hydrogen). , A catalyst for producing methanol having high activity at low temperature), a method for producing the same, and a method for producing methanol using the catalyst.

[0008]

The object of the present invention is to subject a lanthanoid compound-containing copper oxide to a heat treatment in an inert gas,
Then, a catalyst for methanol production, comprising a lanthanoid oxide-containing reduced copper obtained by subjecting the lanthanoid oxide and copper particles having a particle size of 180Å or less to each other, obtained by a reduction treatment, a method for producing the same, and the catalyst are described. This is achieved by the method of producing methanol used.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As the lanthanoid compound-containing copper oxide of the present invention, a lanthanoid compound-containing copper oxide represented by the general formula (M _x Cu _y ) ₇ O _z A _w (where M is Dy, At least one lanthanoid atom selected from the group consisting of Ho, Er, Tb, Tm, Yb and Lu is shown, A is a NO ₃ group and / or a halogen atom, and x +
y = 1, 0 <x / y ≦ 10, 6 ≦ z ≦ 8, 0.5 ≦ w ≦
9) is preferred. The lanthanoid compound-containing copper oxide represented by the above general formula is a cubic crystal and is used as a precursor of the catalyst for methanol production of the present invention. The halogen atom is preferably a chlorine atom. A part of this lanthanoid compound-containing copper oxide is described in Japanese Patent Application Laid-Open No. 5-43228 related to the application of the present applicant, and the description of the specification can be incorporated as a part of the specification of the present application.

The lanthanoid compound-containing copper oxide (catalyst precursor) includes Dy (dysprosium), Ho (holmium), Er (erbium), Tb (terbium),
Tm (thulium), Yb (ytterbium) and Lu
A predetermined amount of a compound of at least one lanthanoid element selected from the group consisting of (lutetium) and a nitrate of copper are mixed, and the mixture is heated at 150 to 650 ° C., preferably 250
Prepared by heating at ~ 450 ° C. As the compound of the lanthanoid element, at least one of the oxides, nitrates and chlorides of the lanthanoid element is used.

When the heating temperature exceeds 650 ° C., Cu
O and / or oxides of Dy, Ho, Er, Tb, Tm, Yb or Lu are separately formed and are not uniform, which is not preferable. The heating temperature is 150 ° C.
If it is less than the above range, the reaction for producing the lanthanoid compound-containing copper oxide from various metal salts does not proceed smoothly, which is not preferable. The above heating is preferably carried out using a normal heating device such as an electric furnace while removing a volatile decomposition product under the flow of a gas such as oxygen, nitrogen or air or under reduced pressure. The heating time is appropriately selected within the range of 1 minute to 50 hours.

The lanthanoid compound-containing copper oxide (catalyst precursor) thus prepared has a 2θ of 16.0.
16.8 °, 29.5-34.0 °, 37.8-39.
It is a compound having characteristic X-ray diffraction spectrum peaks of 5 °, 41.0 to 43.0 °, and 54.6 to 57.0 °. These peaks are assigned to the plane indices 111, 222, 400, 331 and 440 of the cubic crystal, respectively. The axial length a of this crystal is about 9.2 to 9.
It is 8Å.

From the X-ray diffraction spectrum data, this lanthanoid compound-containing copper oxide (catalyst precursor) was identified as Ag.
It is recognized as a cubic crystal having a composition similar to ₇ O ₈ (NO ₃ ). Specifically, for example, when ytterbium oxide is used as the lanthanoid compound, the lanthanoid compound-containing copper oxide (ytterbium compound-containing copper oxide) is a lanthanoid represented by a copper atom and M in a cubic crystal lattice. It is recognized as a compound in which atoms (ytterbium atoms) are regularly arranged, and copper atoms and lanthanoid atoms (ytterbium atoms) are mixed at an atomic level.

In the present invention, the lanthanoid compound-containing copper oxide (catalyst precursor) prepared as described above is further heat-treated in an inert gas before being subjected to the reduction treatment so that the desired activity and selectivity can be obtained. An excellent catalyst for methanol production can be obtained. By this heat treatment of the lanthanoid compound-containing copper oxide (catalyst precursor), NO ₃ groups and / or halogen atoms are partially removed from the lanthanoid compound-containing copper oxide without destroying its crystal structure, It becomes possible to control the size of the copper particles during the reduction. Nitrogen gas,
The above-mentioned lanthanoid compound-containing copper oxide (catalyst precursor) in or under an atmosphere of an inert gas such as argon gas
At 350-650 ° C, preferably 350-500 ° C,
It is carried out by heating for 0.5 to 20 hours, preferably 1 to 10 hours. When the heat treatment temperature exceeds 650 ° C., the lanthanoid compound-containing copper oxide is decomposed to form copper oxide and lanthanoid oxide, which is not preferable. When the lanthanoid compound-containing copper oxide contains a NO ₃ group, the heat treatment temperature is particularly preferably 350 to 500 ° C.
Further, when the heat treatment temperature is lower than 350 ° C., the above-mentioned treatment effect is not sufficient and a catalyst for methanol production excellent in activity and selectivity cannot be obtained.

The heat-treated lanthanoid compound-containing copper oxide is then reduced at a relatively low temperature. When the reduction temperature is too high, sintering occurs, and when the reduction temperature is low, the reduction does not proceed. Therefore, this reduction treatment is performed by reducing the lanthanoid compound-containing copper oxide at 200 to 350 ° C. with a reducing gas such as hydrogen or carbon monoxide. By contacting with a gas containing. The reduction treatment can be performed under any conditions of normal pressure, increased pressure and reduced pressure, and the reduction time is, for example, 0.1 to 10 hours, although it depends on the reduction conditions. Note that this reduction treatment may be carried out by putting the lanthanoid compound-containing copper oxide in a reactor different from the reactor for methanol production and raising the temperature to a predetermined temperature while circulating a reducing gas. It is also possible to charge the lanthanoid compound-containing copper oxide and the reducing gas into the reactor for use and then raise the temperature to a predetermined temperature before the methanol production.

The lanthanoid oxide-containing reduced copper obtained as described above is a mixture of lanthanoid oxide and copper reduced to metallic copper (X-ray photoelectron spectroscopy spectrum and transmission electron microscope ( TEM)),
The particle size of the copper particles reduced to metallic copper was 180 Å or less (according to X-ray diffraction spectrum). Such reduced lanthanoid oxide-containing copper, that is, lanthanide oxide, has a particle size of 180Å or less, particularly 50 to 180.
Å, preferably 100-180 Å, more preferably 12
The reduced lanthanide oxide-containing copper mixed with 0 to 180Å copper particles is used as a catalyst for methanol production having excellent activity and selectivity in a method for producing methanol from carbon monoxide and / or carbon dioxide and hydrogen. It is preferably used.

In the present invention, methanol is produced by reacting carbon monoxide and / or carbon dioxide with hydrogen in the gas phase or liquid phase in the presence of the above-mentioned reduced copper containing lanthanoid oxide. The form in which the lanthanoid oxide-containing reduced copper is present in the reaction system is not particularly limited, and may be present as it is, for example, in the form of a granular or fine powder, or supported on a granular or fine powder carrier. It may be present in a different form. In the gas phase reaction, the lanthanoid oxide-containing reduced copper is preferably present in a fixed bed or a fluidized bed in the form of particles or fine powder.

The reaction in the gas phase is carried out in a normal atmospheric pressure or elevated pressure flow system or in a reduced pressure closed circulation system at a reaction temperature of 150 to 300 in the presence of the above-mentioned reduced copper containing lanthanoid oxide.
℃, preferably 180-250 ℃, gas hourly space velocity is 10
0 to 20000 hr ^-1 , preferably 3000 to 1000
It is performed under the condition of ⁰ hr ^-1 . When the reaction is carried out under pressure, the reaction pressure is 1 to 120 kg / cm ² G, preferably 10 to
120 kg / cm ² G, more preferably 20-50 kg
/ Cm ² G, 5 torr when the reaction is performed under reduced pressure
From the above, less than 760 torr, preferably 50 to 500
is torr.

The reaction in the liquid phase is a pressure flow system or a pressure batch system in the presence of the above-mentioned reduced copper containing lanthanoid oxide, in the same temperature, pressure, gas composition, and gas phase reaction as in the gas phase reaction.
It is done at gas space velocity. That is, the reaction temperature is 150 to 3
The reaction pressure is 1 to 00 ° C, preferably 180 to 250 ° C.
120 kg / cm ² G, preferably 10-120 kg /
cm ² G, more preferably 20 to 50 kg / cm ² G. And in the case of a pressurized distribution system, the gas space velocity is 1
00 to 20000 hr ^-1 , preferably 3000 to 100
The reaction is carried out under the condition of 00 hr ^-1 . In the case of the liquid phase reaction, the reaction is carried out in a solvent, and the lanthanoid oxide-containing reduced copper is added to the solvent in an amount of 1 to 60, for example.
It is used by suspending it in a solvent at a ratio of 5% by weight, preferably 5 to 50% by weight.

The solvent may be any solvent which is stable under the reaction conditions and which can suspend the catalyst, and includes, for example, (1) a halogen atom having 6 to 20 carbon atoms such as hexane, heptane, octane, decane and dodecane. Not aliphatic hydrocarbons,
(2) Carbon number 6 to 1 such as benzene, toluene and xylene
An aromatic hydrocarbon of 2, an ether such as (3) dimethyl ether, diethyl ether, diisopropyl ether,
At least one solvent selected from (4) ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, and (5) aliphatic halogenated hydrocarbons such as dichloromethane, chloroform and dichloroethane can be used. It is also possible to use a commercially available paraffin-based or naphthene-based mineral oil as it is.

The carbon monoxide, carbon dioxide and hydrogen used in the production of the methanol of the present invention may be a mixture of pure gases, but normally those industrially obtained as synthesis gas or water gas are preferably used. To be done. The ratio of hydrogen to carbon monoxide or carbon dioxide in these gases is hydrogen: carbon monoxide (H ₂ : CO) or hydrogen: carbon dioxide (H ₂ : CO 2).
CO ₂ ) in a volume ratio of 10: 1 to 1: 5, preferably 5:
It can be set in a wide range of 1 to 1: 2. When carbon monoxide and carbon dioxide coexist, the ratio [H ₂ : (CO + CO ₂ )] of hydrogen to the total amount thereof is within the above range, that is, 10: 1 to 1: 5. It can take a value. The concentrations of nitrogen, methane, etc. coexisting in these gases are not particularly limited. After completion of the reaction, the produced methanol is easily separated and purified by distillation or the like in both gas phase reaction and liquid phase reaction.

[0022]

EXAMPLES Next, the present invention will be described with reference to Examples and Comparative Examples.
Explain physically. Example 1 7.18 g (18.22 mmol) of ytterbium oxide
And 52.8 g (218 mmol) of copper nitrate trihydrate in a mortar
Grind in the middle, mix well, and at 330 ° C under air circulation.
Heated for 2 hours. As a result, copper containing lanthanoid compounds
As an oxide, a cubic X-ray diffraction pattern (CuKα
Line use: 2θ = 16.4 ° [111], 33.2 ° [2
22], 38.5 ° [400], 42.1 ° [33
1], 55.6 ° [440]) ytterbium
Compound-containing copper oxide [(Yb_1/7Cu _6/7)₇O₈NO
_Three] 27.5g was produced.

Next, this ytterbium compound-containing copper oxide (catalyst precursor) was heated at 400 ° C. for 1 hour in a nitrogen gas atmosphere to be heat-treated. After completion of the heat treatment, 0.05 g of the ytterbium compound-containing copper oxide was charged into a glass reaction tube having an inner diameter of 12 mm, and the temperature was gradually increased while circulating hydrogen gas at 100 ml / min in a closed circulation system under a pressure of 400 torr. A reduction treatment was performed at 200 ° C. for 2 hours to obtain ytterbium oxide-containing reduced copper as the lanthanoid oxide-containing reduced copper.

After completion of the reduction treatment, hydrogen gas was exhausted, and the obtained reduced copper containing ytterbium oxide was used as a catalyst for 40
Under a pressure of 0 torr, reaction was carried out at 200 ° C. for 8 hours while circulating a mixed gas of H ₂ : CO (volume ratio) = 3: 1 in a closed circulation system to produce methanol. After completion of the reaction, the produced methanol was cooled and collected with liquid nitrogen and analyzed by gas chromatography (TCD). As a result, the produced amount of methanol was 327 μmol / g-cat.
Met.

The ytterbium oxide-containing reduced copper obtained as described above has an X-ray diffraction pattern (CuKα
Line use: 2θ = 43.3 °, 50.3 °), the particle size of copper particles reduced to metallic copper was 166Å, and the diffraction peak of ytterbium oxide was not observed.
In addition, from the X-ray photoelectron spectroscopy spectrum and the transmission electron microscope (TEM), copper reduced to metallic copper and ytterbium oxide were mixed.

Comparative Example 1 A catalyst was prepared in the same manner as in Example 1 except that the ytterbium compound-containing copper oxide (catalyst precursor) was not heat-treated in a nitrogen gas atmosphere. Manufacturing and product analysis was performed. As a result, the amount of methanol produced was 295 μmol / g-cat. Met.

Example 2 A catalyst was prepared in the same manner as in Example 1 except that the temperature of the reduction treatment was changed to 250 ° C. and methanol was produced and the product was analyzed. As a result, the amount of methanol produced was 580 μmol / g-cat. Met.

Examples 3 to 5 Catalysts were prepared in the same manner as in Example 1 except that the temperature of the reduction treatment and the reaction temperature of methanol production were changed as shown in Table 1 to produce methanol. The product was analyzed. Table 1 shows the results.

Comparative Example 2 A catalyst was prepared in the same manner as in Example 1 except that the reduction treatment was carried out at 400 ° C., and methanol was produced and the product was analyzed. As a result, the amount of methanol produced was 280 μmol / g-cat. Met. Example 1
The results of No. 5 and Comparative Examples 1 and 2 are shown in Table 1.

[0030]

[Table 1]

[0031] In Example 6 Example _2, H 2: CO (volume ratio) = 3: Instead of the gas mixture of 1, H _2: CO ₂ (volume ratio) = 3: addition to using one of the mixed gas In the same manner as in Example 2, a catalyst was prepared and methanol was produced and the product was analyzed. As a result, the amount of methanol produced was 485 μmol / g-cat.
Met.

Example 7 In Example 2, a mixed gas of H ₂ : CO ₂ (volume ratio) = 6: 1 was used instead of the mixed gas of H ₂ : CO (volume ratio) = 3: 1. In the same manner as in Example 2, a catalyst was prepared and methanol was produced and the product was analyzed. As a result, the amount of methanol produced was 625 μmol / g-cat.
Met.

Comparative Example 3 In Example 1, an industrial methanol production catalyst (CuO: ZnO: Al ₂ O ₃ (weight ratio) = 42) made of CuO—ZnO—Al ₂ O ₃ was used instead of the reduced copper containing ytterbium oxide. 0.5: 47.5: 10) 0.05 g to 350
Production of methanol and analysis of products were carried out in the same manner as in Example 1 except that the reaction was carried out at 250 ° C. using the catalyst reduced at ° C. As a result, the amount of methanol produced is 134 μm.
ol / g-cat. Came out.

Comparative Example 4 In Example 1, an industrial methanol production catalyst (CuO: ZnO: Cr ₂ O ₃ (weight ratio) = 60, which was made of CuO—ZnO—Cr ₂ O ₃ instead of the reduced copper containing ytterbium oxide, was used. : 30: 30) The production of methanol and analysis of the product were carried out in the same manner as in Example 1 except that the reaction was carried out at 250 ° C. using a catalyst obtained by reducing 0.05 g at 300 ° C. As a result, the amount of methanol produced was 121 μmol / g
-Cat. Came out.

[0035]

INDUSTRIAL APPLICABILITY According to the present invention, in a method for producing methanol by reacting carbon monoxide and / or carbon dioxide with hydrogen, a highly active catalyst for producing methanol, that is, high activity even at low temperature (200 ° C.) Methanol can be efficiently produced using the catalyst for producing methanol.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI technical display location // C07B 61/00 300 C07B 61/00 300 (72) Inventor Ryoji Sugise Ube-shi, Yamaguchi Prefecture 1978 number Kogushi 5 Inside the Ube Laboratory at Ube Industries, Ltd.

Claims (5)

[Claims] 1. A lanthanoid oxide-containing reduction containing a mixture of lanthanoid oxide and copper particles having a particle size of 180Å or less, which is obtained by heat-treating a lanthanoid compound-containing copper oxide in an inert gas and then subjecting it to a reduction treatment. Catalyst for methanol production consisting of copper. 2. The lanthanoid compound-containing copper oxide is a lanthanoid compound-containing copper oxide represented by the general formula (M _x Cu _y ) ₇ O _z A _w (where M is Dy, Ho, Er, T).
b, Tm, Yb and at least one lanthanoid atom selected from the group consisting of Lu, A represents a NO ₃ group and / or a halogen atom, x + y = 1, 0 <x / y ≦
10, 6 ≦ z ≦ 8, 0.5 ≦ w ≦ 9), The catalyst for methanol production according to claim 1. 3. The catalyst for methanol production according to claim 1, wherein the copper particles have a particle size of 50 to 180Å. 4. A copper oxide containing a lanthanoid compound is heat-treated at 350 to 650 ° C. in an inert gas, and then 200
The method for producing a catalyst for methanol production according to claim 1, wherein the reduction treatment is performed at ˜350 ° C. 5. A method for producing methanol, which comprises reacting carbon monoxide and / or carbon dioxide with hydrogen in the presence of the catalyst for producing methanol according to claim 1.