JPH0669969B2 - Hydrocarbon production method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a hydrocarbon having 2 or more carbon atoms such as ethane and ethylene from methane as a raw material.

[Conventional technology]

Methane is abundant as a main component of natural gas, but its low reactivity makes it difficult to use as a raw material for chemical industry. Therefore, conventionally, as a method of producing a hydrocarbon having 2 or more carbon atoms by oxidative coupling of methane, a method of using a catalyst in which lithium is supported on magnesium oxide is known (J. Am. Chem. Soc). ., 1985, 107 , 58
−63; Catalyst, 27 , (6), 443 (1985)).

However, in these methods, satisfactory results have not yet been obtained in terms of the yield of the methane compound having 2 carbon atoms.

[Problems to be solved by the invention]

The present invention provides a method for producing a hydrocarbon having 2 or more carbon atoms from methane, which improves the conversion rate of methane and the yield of a compound having 2 carbon atoms.

[Means for solving problems]

The present inventor has conducted various studies on a catalyst for oxidative coupling of methane, and as a result, by using a catalyst for oxidative coupling of a specific methane having a specific specific surface area, a high conversion rate from methane, ethane, ethylene, etc. It was found that a hydrocarbon having 2 or more carbon atoms can be produced in good yield, and based on this finding, the present invention has been completed.

That is, in the method for producing a hydrocarbon of the present invention, when methane is contacted with a catalyst in the presence of oxygen to produce a hydrocarbon having 2 or more carbon atoms, oxidation of a metal selected from alkali metals and alkaline earth metals is carried out. Or a carbonate or a catalyst comprising at least one other metal component supported on these compounds and having a specific surface area of 50 m ² / g or less is used. As the catalyst used in the present invention, an oxide or carbonate of a metal selected from alkali metals and alkaline earth metals or a compound obtained by supporting one or more other metal components on these compounds is used. Lithium, sodium, potassium, rubidium or cesium is used as the alkali metal, and magnesium, calcium, strontium or barium is used as the alkaline earth metal,
Specific examples of oxides and carbonates of these metals include
Examples thereof include lithium carbonate, magnesium carbonate, strontium carbonate, barium carbonate, magnesium oxide and calcium oxide, and magnesium oxide is preferably used.

In the present invention, the above-mentioned oxide or carbonate may be used alone as the catalyst, but it is preferable to use those compounds carrying one or more other metal components. The yield of ethane and ethylene is improved by using the supported catalyst.

Other metal components include alkali metals, alkaline earth metals or Group IB, Group IIB, Group IIIA, Group IIIB of the Periodic Table.
Clan, IVA, IVB, VA, VB, VIB, V
Group IIB or Group VIII metals are used. Lithium, sodium, potassium, rubidium and cesium are used as the alkali metal, and magnesium, calcium, strontium, barium and the like are used as the alkaline earth metal. Further, copper and silver are used as Group IB metals, zinc is used as Group IIB metals, aluminum and indium are used as Group IIIA metals, and yttrium or lanthanum and samarium are used as Group IIIB metals. Lanthanoid metals, lead as Group IVA metal, zirconium as Group IVB metal, bismuth as Group VA metal, vanadium as Group VB metal, as Group VIB metal. Is preferably chromium, the group VIIB metal is manganese, and the group VIII metal is preferably cobalt, iron or nickel.

In the present invention, the specific surface area of these catalysts needs to be 50 m ² / g or less. 2 carbon atoms when the specific surface area exceeds 50 m ² / g
The yield of hydrocarbons is reduced. From the viewpoint of hydrocarbon yield, the specific surface area is preferably ² to 30 m ² / g.

The catalyst used in the present invention can be prepared, for example, as follows. If necessary, the oxide or carbonate is impregnated with an aqueous solution of an alkali metal salt such as lithium sulfate, sodium sulfate, or potassium sulfate and an alkaline earth metal salt such as barium sulfate or strontium sulfate, or an aqueous solution of the other metal. , Which is evaporated to dryness at 100-200 ° C. Then, if necessary, this is fired at 500 to 700 ° C. in air for 0.5 to 30 hours. In the present invention, a catalyst having a specific surface area of 50 m ² / g or less is used, and in order to control the specific surface area of this catalyst to 50 m ² / g or less, annealing performed on the catalyst obtained by firing is performed. This is performed by controlling the conditions and the amount of metal supported on the catalyst. Annealing is preferably performed at 800-1200 ℃ in air or helium for 2 hours or more. The amount of metal supported is 0-20mo.
It is preferably 1%.

The obtained catalyst is pulverized or pelletized by a compression method, if necessary.

The specific surface area of the catalyst was measured by the BET method.

The catalyst thus obtained was charged with methane at 500 to 1000 ° C.
When contacted in the presence of oxygen at 1, a hydrocarbon having a higher carbon number than methane is obtained.

If the reaction temperature is less than 500 ° C, the reaction hardly progresses, and if the reaction temperature exceeds 1000 ° C, the catalyst deteriorates severely.
The temperature is preferably 0 to 800 ° C.

The methane used in the method for producing hydrocarbons of the present invention is not limited to methane itself, but methane in natural gas can be used. Further, oxygen in the air can also be used as oxygen. Methane and oxygen are allowed to exist in the reaction system at CH ₄ / O ₂ (molar ratio) = 0.1 to 10 to carry out a catalytic partial oxidation reaction. In addition to methane and oxygen, an inert gas such as helium or argon may be present. The reaction is usually
It is carried out by a normal pressure flow method, but if necessary, it may also be carried out under reduced pressure or under increased pressure, usually at a normal pressure to 100 kg / cm ² G. The gas space velocities of methane and oxygen in this reaction are 30 hr ^{-1 to} 400,000 h depending on the reaction temperature and the desired conversion rate.
It is determined in the range up to r ^-1 .

Further, in the present invention, the catalyst can be used in any of a fixed bed, a fluidized bed and a moving bed.

By converting methane to ethane or ethylene by the method of the present invention, it can be used as a petrochemical raw material for the production of ethylene oxide, ethylbenzene, ethyl chloride, ethylene dichloride, ethylene alcohol, polyethylene, etc. It is possible to obtain the final product.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is in no way limited by these examples.

Example 1 A commercially available magnesium oxide powder was calcined at 500 ° C. for 1 hour,
After that, annealing was performed at 1000 ° C. for 2 hours while purging with helium to obtain a specific surface area of 17 m ² / g (BET method). 2g of this catalyst (powder) was put into a quartz glass reaction tube and placed in an electric furnace for 75
Methane 1.5 ml / min, air 37.5 ml / min while heating to 0 ℃
A gas obtained by diluting the mixed gas of helium with 50 ml / min of helium was introduced and reacted. The obtained product was analyzed by gas chromatography. The results are shown in Table 1.

Comparative Example 1 The same procedure as in Example 1 was carried out, except that a catalyst having an annealing temperature of 800 ° C. and a specific surface area of 70 m ² / g was used. The results are shown in Table 1.

Example 2 A commercially available magnesium oxide powder was impregnated with a sodium sulfate aqueous solution so as to have a concentration of 0.2 mol%, and then dried, and the temperature was 500 ° C.
After firing for 1 hour at 1000 ° C., annealing was performed at 1000 ° C. for 2 hours while purging with helium to obtain a specific surface area of 7 m ² / g.
The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Example 3 The procedure of Example 2 was repeated, except that the amount of sodium sulfate supported was 5.0 mol%, the annealing temperature was 800 ° C., and the specific surface area was 11 m ² / g. The results are shown in Table 1.

Example 4 Example 4 was carried out in the same manner as in Example 2 except that a catalyst having a supported amount of sodium sulfate of 15.0 mol%, an annealing temperature of 800 ° C. and a specific surface area of 2 m ² / g was used. The results are shown in Table 1.

Comparative Example 2 Example 2 was repeated except that the annealing temperature was 800 ° C. and the specific surface area was 212 m ² / g. The results are shown in Table 1.

Example 5 Lithium sulfate aqueous solution was added to commercially available magnesium oxide powder.
After impregnation to 1.3 mol%, the mixture was dried, calcined at 500 ° C. for 1 hour, and then annealed at 850 ° C. for 2 hours while purging with helium to have a specific surface area of 2 m ² / g. The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Example 6 Commercially available magnesium oxide powder was impregnated with an aqueous strontium sulfate solution to an amount of 5.0 mol%, and then dried.
It was baked at 00 ° C. for 1 hour and then annealed at 850 ° C. for 2 hours while purging with helium to make the specific surface area 14 m ² / g. The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Comparative Example 3 A specific surface area of 5 was obtained in the same manner as in Example 6 except that the baking was performed at 550 ° C. for 1 hour and the annealing temperature was 750 ° C.
9 m ² / g of catalyst was obtained. The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Example 7 A barium sulfate aqueous solution was added to a commercially available magnesium oxide powder.
Impregnate to 5.0 mol% and dry, then at 500 ℃ 1
It was calcined for an hour and then annealed at 850 ° C. for 2 hours while purging with helium to make the specific surface area 6 m ² / g. The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Example 8 To a commercially available magnesium oxide powder, a potassium sulfate aqueous solution was added.
Impregnate to 2.0 mol% and dry,
It was calcined for an hour and then annealed at 1000 ° C. for 2 hours while purging with helium to make the specific surface area 10 m ² / g. The reaction conditions were the same as in Example 1 except that the reaction temperature in Example 1 was 800 ° C. The results are shown in Table 1.

Comparative Example 4 The same procedure as in Example 8 was carried out except that a catalyst having an annealing temperature of 800 ° C. and a specific surface area of 66 m ² / g was used. The results are shown in Table 1.

[Effect of the Invention] The method for producing a hydrocarbon having 2 or more carbon atoms from methane of the present invention is excellent in the conversion rate of methane and the yield of a compound having 2 carbon atoms, and its industrial value is extremely large.

Claims (4)

[Claims] 1. When contacting methane with a catalyst in the presence of oxygen to produce a hydrocarbon having 2 or more carbon atoms, an oxide or carbonate of a metal selected from an alkali metal and an alkaline earth metal, or a metal oxide or a carbonate thereof. A process for producing a hydrocarbon, which comprises using a catalyst having one or more other metal components supported on a compound and having a specific surface area of 50 m ² / g or less. 2. The method for producing a hydrocarbon according to claim 1, wherein the alkali metal is lithium, sodium, potassium, rubidium or cesium. 3. The method for producing a hydrocarbon according to claim 1, wherein the alkaline earth metal is magnesium, calcium, strontium or barium. 4. The other metal component is an alkali metal, an alkaline earth metal, or Group IB, Group IIB, Group IIIA, or Group I of the periodic table.
IIB group, IVA group, IVB group, VA group, VB group, VIB group,
The method for producing a hydrocarbon according to claim 1, which is a Group VIIB or Group VIII metal.