JPH09253495A - Methanol synthesis catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To synthesize methanol with high activity and durability by using a gas primarily consisting of hydrogen and carbon monoxide by using a catalyst containing oxides of at least copper, zinc, aluminum and gallium and further containing metal oxides of manganese, chromium and the like. SOLUTION: A synthetic gas primarily consisting of hydrogen and carbon monoxide and/or carbon dioxide is used to synthesize methanol. A matter containing oxides of at least copper, aluminum and gallium and further containing at least one metal oxide of manganese, chromium, niobium, vanadium and indium oxide is used as a catalyst in synthesizing. Since the catalyst contains highly dispersed copper, the catalyst exhibits a high activity for synthesis of methanol and the activity can be maintained for a long time.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a catalyst for synthesizing methanol from a gas containing hydrogen (H ₂ ) and carbon monoxide (CO) as main components.

[0002]

2. Description of the Related Art The research and development of a methanol synthesis catalyst has been conducted for a long time, and a catalyst having a composition such as zinc oxide-chromium oxide or copper oxide-zinc oxide is prepared by a coprecipitation method or the like. In particular, a ternary or quaternary catalyst composed of copper oxide-zinc oxide-aluminum oxide and / or chromium oxide has high methanol synthesis activity and is widely used. On the other hand, methanol is MTBE (methyl tertiary
Butyl ether), gasoline, petrochemical intermediate products, raw materials for the production of hydrogen, carbon monoxide, city gas, etc., and for fuel, it is expected that demand will increase more and more in the future. A synthesis plant is expected to be built. In addition, methanol is currently produced by using a gas containing hydrogen and carbon monoxide as main components, which is produced by a steam reforming reaction of natural gas, as a raw material and contacting it with the above-mentioned three-way catalyst.

In addition to the above-mentioned three-way catalyst or four-way catalyst, a catalyst composed of copper oxide-zinc oxide-manganese oxide (Japanese Patent Publication No.
6-9376), a catalyst composed of copper oxide-zinc oxide-silicon oxide (JP-B-63-39287), and a catalyst composed of copper oxide-zinc oxide-gallium oxide (JP-A-6-36
However, since it is difficult to say that the activity of synthesizing methanol is low and the life is long, it is desired to develop a high-performance methanol synthesis catalyst.

[0004]

The catalyst composed of each oxide of copper, zinc and aluminum has a high methanol synthesis activity, but has a problem that the activity decreases with time. In view of the above technical level, the present invention intends to provide a catalyst having high activity and excellent durability.

[0005]

[Means for Solving the Problems] As a result of earnestly carrying out research and development of a catalyst that exceeds the performance of existing methanol synthesis catalysts, the present inventors have highly dispersed copper, which plays the most important role in methanol synthesis activity, Moreover, the inventors have found a methanol synthesis catalyst with a small decrease in activity and completed the present invention. That is, the present invention contains, as a catalyst for synthesizing methanol from a synthesis gas containing hydrogen and carbon monoxide and / or carbon dioxide as main components, at least oxides of copper, zinc, aluminum and gallium, and further contains manganese (Mn ), Chromium (Cr), niobium (Nb), vanadium (V), indium (In), and at least one metal oxide.

[0006]

The preferred composition ratio (atomic ratio) of the methanol synthesis catalyst of the present invention is Cu: Zn: Al: Ga: α.
= 100: 10 to 200: 1 to 20: 1 to 20: 1 to 2
0. Here, α represents one or more metals of Mn, Cr, Nb, V, and In.

Hereinafter, an example of the method for producing the methanol synthesis catalyst of the present invention will be described in more detail. First, while keeping the precipitant aqueous solution warm and stirring, an aqueous solution containing one or more metals of Mn, Cr, Nb, V and In and each metal salt of Al, Ga and Zn is dropped to deposit a precipitate. After the dropping, an aqueous solution containing Cu is then dropped to form a precipitate. When the pH at the end of dropping is 4 or more, almost all the dropped metal ions are deposited as a precipitate.

The precipitant aqueous solution is an alkaline solution,
Usually 0.1 to 10M concentration of Na_TwoCO _ThreeAqueous solution, NaH
CO_ThreeAqueous solution, NaOH aqueous solution, K_TwoCO_ThreeAqueous solution, N
H_ThreeUsed as an aqueous solution, especially Na_TwoCO_ThreeWater soluble
Liquids are preferred. In addition, the temperature of the solution when forming the precipitate
It is preferable to keep the temperature in the range of 15 to 90 ° C.

Further, Cu, Zn, Al, Ga and M
The metal salts of n, Cr, Nb, V, and In are used in the form of nitrates, chlorides, sulfates, and nitrates as an aqueous solution having a concentration of 0.01 to 1.0 M, and particularly preferably used as nitrates. Further, the dropping time and the aging time have no particular influence on the methanol synthesis activity of the catalyst, but they may be the conditions under which the metal ions are uniformly dispersed and the precipitate is deposited. Usually, the dropping time: 1 minute to 3 hours, the aging time It is carried out for 1 minute to 3 hours. The resulting precipitate has various crystal species,
After thoroughly removing alkali metal ions and anions,
A methanol synthesis catalyst is obtained by firing in the range of 200 to 400 ° C.

By using the catalyst of the present invention, a gas containing H ₂ and CO or a gas containing H ₂ , CO and CO ₂ is used as a synthesis gas as a raw material for a methanol synthesis reaction, and pressure:
It is possible to synthesize methanol with long-term and stable performance at a temperature of 200 kg / cm ² G or less and a temperature of 100 to 300 ° C.

[0011]

EXAMPLES The present invention will be described in more detail with reference to the following examples, and the effects of the catalyst of the present invention will be clarified. However, the description of the examples is not limited unless the essence of the present invention is impaired. is not.

(Example 1) Sodium carbonate: 2.5 mo
1 is dissolved in 2 liters of water and kept warm at 60 ° C. This alkaline aqueous solution is referred to as solution A. Zinc nitrate: 0.18mo
1 and aluminum nitrate: 0.03 mol, gallium nitrate: 0.015 mol, and chromium nitrate: 0.015 mo
1 is dissolved in 600 cc of water and kept at 60 ° C., and this acidic solution is referred to as solution B. Furthermore, copper nitrate: 0.3 mol
Is dissolved in 300 cc of water and kept at 60 ° C., and this acidic solution is referred to as solution C.

First, the solution B is added to the solution A with stirring 30 times.
A uniform suspension is added dropwise over a minute to obtain a suspension. Next, solution C
Was added dropwise to the suspension at a constant rate over 30 minutes, and
Get the item. After dropping, aging for 2 hours, then the precipitate
Filtration and Na ion, NO _ThreeIons are not detected
To wash. Further, it is dried at 100 ° C. for 24 hours,
Methanol synthesis by baking at 300 ° C for 3 hours
The catalyst is referred to as catalyst 1.

(Example 2) Zinc nitrate in solution B: 0.3 mo
1, aluminum nitrate: 0.05 mol, gallium nitrate: 0.03 mol, indium nitrate: 0.03 mol
A methanol synthesis catalyst was prepared by the same preparation method as in Example 1 except that was used. This catalyst is referred to as catalyst 2. Further, in the liquid B, zinc nitrate: 0.15 mol, aluminum nitrate: 0.015 mol, gallium nitrate: 0.015 m
Ol, manganese nitrate: 0.015 mol, and in the solution B, zinc nitrate: 0.15 mol, aluminum nitrate: 0.
006 mol, gallium nitrate: 0.006 mol, niobium nitrate: 0.006 mol, and liquid B: zinc nitrate:
0.15 mol, aluminum nitrate: 0.006mo
1, gallium nitrate: 0.006 mol, and vanadium chloride 0.006 mol were prepared in the same manner as in Example 1 to obtain catalyst 3, catalyst 4, and catalyst 5.

Example 3 Example 1 was repeated except that the solutions A, B and C having the same composition as the catalyst 1 of Example 1 were used and the mixed solution of the solutions B and C was added dropwise to the solution A. Catalyst 6 was obtained in the same manner.

(Example 4) Zinc nitrate in solution B: 0.15 m
ol, aluminum nitrate: 0.009 mol: gallium nitrate: 0.006 mol, chromium nitrate: 0.006 mo
1, vanadium chloride: A methanol synthesis catalyst was prepared by the same preparation method as in Example 1 except that 0.006 mol was used. This catalyst is referred to as catalyst 7. Further, in the liquid B, zinc nitrate: 0.15 mol, aluminum nitrate: 0.00
9 mol, gallium nitrate: 0.006 mol, manganese nitrate: 0.006 mol, indium nitrate: 0.006
A methanol synthesis catalyst was prepared in the same manner as in Example 1 except that mol was used. This catalyst is referred to as catalyst 8.

(Comparative Example 1) The same procedure as in Example 1 was repeated except that chromium nitrate was not added and gallium nitrate or aluminum nitrate was not added.
Composition _{CuO-ZnO-Al 2 O 3} (Cu: Zn: Al
= 100: 60: 10) catalyst 9 and CuO-ZnO-G
A catalyst 10 of a ₂ O ₃ (Cu: Zn, Ga = 100: 60: 10) was prepared. Moreover, in the preparation method of Example 1, the composition was CuO-ZnO-SiO by the same method except that silica sol or manganese nitrate was used instead of aluminum nitrate, gallium nitrate and chromium nitrate.
₂ (Cu: Zn: Si = 100: 60: 10) catalyst 1
1 and _{CuO-ZnO-MnO x (Cu} : Zn: Mn = 1
Catalyst 12 of 00:60:10, x = 1.5 to 2) was prepared.

(Example) An activity evaluation test of the methanol synthesis reaction of the catalysts 1 to 12 obtained in Examples 1 to 4 and Comparative Example was conducted under the conditions shown in Table 1 below.

[0019]

[Table 1]

The catalyst was sized to 16 to 28 mesh, charged into a ₂ cc microreactor, subjected to a reduction treatment with H ₂ 3% / N ₂ base gas, and then a raw material gas was supplied to evaluate the initial activity. Table 2 shows the results of evaluating the initial activity of each catalyst.

[0021]

[Table 2] The reaction products were all methanol and water. As shown in Table 2, the catalyst prepared in the present invention is the conventional catalyst 9
It was found that the methanol synthesis activity was higher than that of -12.

(Experimental Example 2) Catalysts 1 and 9 used for initial activity evaluation were used as durability test catalysts. The reaction conditions are
Except for the reaction pressure, the same as in Experimental Example 1, the activity results are shown in Table 3.

[0023]

[Table 3] The reaction products were all methanol and water. As shown in Table 3, it was found that the catalyst prepared according to the present invention has a higher methanol synthesis activity than the conventional catalyst and is excellent in durability.

[0024]

The methanol synthesis catalyst of the present invention has a high methanol synthesis activity and can maintain the activity for a long period of time, so that methanol can be efficiently synthesized.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C07C 31/04 B01J 23/84 311Z

Claims (1)

[Claims] 1. A methanol synthesis containing at least each oxide of copper, zinc, aluminum and gallium, and further containing at least one metal oxide of manganese, chromium, niobium, vanadium and indium. catalyst.