JPS6363626A - Production of hydrocarbon - Google Patents

Abstract

PURPOSE:To improve the oxidation conversion of methane and the yield of the objective compound in the production of a >=2C hydrocarbon, by contacting methane with a catalyst in the presence of oxygen using a specific catalyst composed of a specific metal oxide or carbonate, etc., and having a specific surface area. CONSTITUTION:A >=2C hydrocarbon such as ethane, ethylene, etc., is produced by contacting methane with a catalyst in the presence of oxygen. The catalyst used in the above process has a specific surface area of <=50m<2>/g and is produced by using a carrier consisting of an oxide or carbonate of a metal selected from an alkali metal such as Li, Na, K, Rb or Cs, etc., and an alkaline earth metal such as Mg, Ca, Sr or Ba, etc., or a compound of the above metal and supporting a metal other than the above metal, e.g. alkali metal, alkaline earth metal of metal of group IB, IIB, IIIA, IIIB, IVA, IVB, VA, VB, VIB, VIIB or VIII of the periodic table on the carrier. The objective compound can be produced from methane in high yield and conversion.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing hydrocarbons having two or more carbon atoms, such as ethane and ethylene, using methane as a raw material.

[Conventional technology]

Methane is abundant as the main component of natural gas, but its low reactivity makes it difficult to use as a raw material for the chemical industry. Therefore, as a method for producing hydrocarbons having two or more carbon atoms by oxidative cambling of methane, a method using a catalyst in which lithium is supported on magnesium oxide has been known (J, Am, Chem, Soc.
,, 1985.107.58-63; Catalyst, - Shadow 21,
(6), 443 (1985)).

However, these methods have not yet yielded satisfactory results in terms of the yield of methane having two carbon atoms.

[Problem that the invention seeks to solve]

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

[Means for solving problems]

As a result of various studies on catalysts for oxidative coupling of methane, the present inventors have discovered that by using a specific catalyst for oxidative coupling of methane with a specific specific surface area, ethane can be converted from methane at a high conversion rate. It was discovered that hydrocarbons having two or more carbon atoms, such as ethylene, can be produced with good yield, and based on this knowledge, the present invention was completed.

That is, the method for producing hydrocarbons of the present invention involves the oxidation of a metal selected from alkali metals and alkaline earth metals in producing hydrocarbons having 2 or more carbon atoms by contacting methane with a catalyst in the presence of oxygen. A catalyst consisting of one or more other metal components supported on metal or carbonate or a compound thereof, and the specific surface area of the catalyst is 5Qm/
It is characterized by using a material with a weight of less than g.

The catalyst used in the present invention is an oxide or carbonate of a metal selected from alkali metals and alkaline earth metals, or a compound prepared by supporting one or more other metal components on the metal oxide or carbonate. . As the alkali metal, lithium, sodium, potassium, rubidium or cesium is used, and as the alkaline earth metal, magnesium, calcium, strontium or barium is used.
Specifically, oxides and carbonates of these metals include:
Examples include lithium carbonate, magnesium carbonate, strontium carbonate, barium carbonate, magnesium oxide, calcium oxide, etc., and preferably magnesium oxide is used.

In the present invention, the above-mentioned oxides or carbonates may be used alone as the catalyst, but preferably these compounds supported with one or more other metal components are used. By using a supported catalyst, the yield of ethane and ethylene is improved.

Other metal components include alkali metals, alkaline earth metals, or groups 1B, nB, mA, and m of the periodic table.
A metal of Group B, Group (IV), Group 1T/B, Group (IV), Group VB, Group VIB, Group (IV), or Group 1 is used. As the alkali metals, lithium, sodium, potassium, rubidium, and cesium are used; as the alkaline earth metals, magnesium, calcium, strontium, barium, etc. are used; as the Group 1B metals, copper and silver are used; The metal of Group 1IB is zinc, the metal of Group 111A is aluminum or indium, the metal of Group mB is yttrium or lanthanide metals such as lanthanum, samarium, etc.
The group 17A metal is lead, the group B metal is zirconium, the group IVB metal is bismuth, the group VA metal is vanadium, the group VIB metal is chromium, Preferably, manganese is used as the Group 1 B metal, and cobalt, iron, and nickel are used as the Group 1 metals.

In the present invention, the specific surface area of these catalysts is 50rd/
It must be less than g. When the specific surface area exceeds 50rd/g, the yield of hydrocarbons having 2 carbon atoms decreases. From the viewpoint of hydrocarbon yield, the specific surface area is preferably 2 to 30 m2/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 nitrate, sodium nitrate, or potassium nitrate and an alkaline earth metal salt such as barium nitrate or strontium nitrate, or an aqueous solution of the other metal. This is then evaporated to dryness at 100-200°C, and then evaporated to 500-70°C as necessary.
Calcinate in air at 0°C for 0.5 to 30 hours. In the present invention, a catalyst with a specific surface area of 50 rrr/g or less is used, and the specific surface area of this catalyst is SOr+? /g or less is achieved by controlling the annealing conditions applied to the fired catalyst and the amount of metal supported on the catalyst. Annealing is 800-120
The coffin is preferably carried out at 0° C. in air or helium for 2 hours or more, and the amount of metal supported is preferably 0 to 2Qmo1%.

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

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

Methane was added to the catalyst thus obtained at 500-100%
When contacted at 00°C in the presence of oxygen, a hydrocarbon with a higher carbon number than methane is obtained.

If the reaction temperature is less than 500°C, the reaction will hardly proceed,
If the reaction temperature exceeds 100°C, the deterioration of the catalyst will become severe, so it is preferably 700 to 800°C.

As the methane used in the method for producing hydrocarbon Φ of the present invention, not only methane itself but also methane in natural gas can be used. Moreover, oxygen in the air can also be used. Methane and oxygen are in the reaction system, CH410□
(molar ratio)=0.1 to 10, and a catalytic partial oxidation reaction is carried out. Further, in addition to methane and oxygen, an inert gas such as helium or argon may be present. The reaction is usually carried out by the normal pressure flow method, but if necessary,
It can be carried out under reduced pressure or increased pressure, usually at normal pressure to 100k.
It will be held at g/aJG. The gas space velocity of methane and oxygen in this reaction varies from 30 hr-' to 400 hr-' depending on the reaction temperature and desired conversion rate. It can be determined in the range up to OO0hr-'.

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

By converting methane into ethane or ethylene by the method of the present invention, it can be used as a petrochemical raw material for producing ethylene oxide, ethylbenzene, ethyl chloride, ethylene dichloride, ethyl alcohol, polyethylene, etc., and many more can be obtained from these. It becomes possible to obtain the final product.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited in any way by these examples.

Example 1 Commercially available magnesium oxide powder was fired at 500° C. for 1 hour, and then annealed at 1000° C. for 2 hours while purging with helium to give a specific surface area of 17 resistance/g (BET method). 2 g of this catalyst (powder) was placed in a quartz glass reaction tube, and while heated to 750°C in an electric furnace, 1.5 m of methane was added.
j! A mixed gas of 3.75 mff/min of air and diluted with 50 mff/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 was used with an annealing temperature of 800°C and a specific surface area of 10rd/g. The results are shown in Table 1.

Example 2 Commercially available magnesium oxide powder was impregnated with an aqueous sodium nitrate solution to a concentration of 0.2 mol%, and then dried.
Calcined at 00℃ for 1 hour, then annealed at 1000℃ for 2 hours with helium purge to reduce the specific surface area to 7r.
r? /g. The reaction conditions were the same as in Example 1.

The results are shown in Table 1.

Example 3 In Example 2, the supported amount of sodium nitrate was 5.0 mol%, the annealing temperature was 800°C, and the specific surface area was 11r.
The same procedure as in Example 2 was carried out except that a catalyst of rX/g was used. The results are shown in Table 1.

Example 4 In Example 2, the supported amount of sodium nitrate was changed to 15.0
Mol%, annealing temperature 800℃, specific surface area 2f
The same procedure as in Example 2 was carried out except that a catalyst with fl/g was used. The results are shown in Table 1.

Comparative Example 2 The same procedure as in Example 2 was conducted except that the annealing temperature was 800° C. and the specific surface area was 212 rrr/g. The results are shown in Table 1.

Example 5 Commercially available magnesium oxide powder was impregnated with a lithium nitrate aqueous solution to a concentration of 1.3 mol%, and then dried.
It was fired at 0° C. for 1 hour, and then annealed at 850° C. for 2 hours while purging with helium to give a specific surface area of 2d/&. 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 a strontium nitrate aqueous solution to a concentration of 5.0 mol %, dried, baked at 500°C for 1 hour, and then annealed at 850°C for 2 hours while purging with helium. , the specific surface area is 14
m/g. The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Comparative Example 3 A catalyst with a specific surface area of 59%/g was obtained in the same manner as in Example 6, except that the calcination was performed at 550° C. for 1 hour and the annealing temperature was changed to 750° C. The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Example 7 Commercially available magnesium oxide powder was impregnated with an aqueous barium nitrate solution to a concentration of 5.0 mol%, and then dried.
℃ for 1 hour, and then annealed at 850℃ for 2 hours while purging with helium, and the specific surface area was 6r+? /g
The reaction conditions were the same as in Example 1. The results are shown in Table 1.

Example 8 Commercially available magnesium oxide powder was impregnated with an aqueous solution of potassium nitrate to a concentration of 2.0 mol%, and then dried.
℃ for 1 hour, and then annealed at 1000℃ for 2 hours with helium purge to reduce the specific surface area to 10rrr.
/g. The reaction conditions were as in Example 1, with the reaction temperature being 8.
The procedure was the same as in Example 1 except that the temperature was 00°C. The results are shown in Table 1.

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

Blank space below [Effects of the invention] The method of producing hydrocarbons having two or more carbon atoms from methane of the present invention has an excellent conversion rate of methane and a yield of compounds having two carbon atoms, and its industrial value is extremely large. .

Claims (1)

[Claims] 1. Methane is brought into contact with a catalyst in the presence of oxygen to reduce the number of carbon atoms to 2.
In producing the above hydrocarbons, a catalyst consisting of an oxide or carbonate of a metal selected from alkali metals and alkaline earth metals, or a compound thereof with one or more other metal components supported, A method for producing hydrocarbons, characterized in that the catalyst has a specific surface area of 50 m^2/g or less. 2. Alkali metals are lithium, sodium, potassium,
The method for producing a hydrocarbon according to claim 1, which is rubidium or cesium. 3. Claim 1 in which the alkaline earth metal is magnesium, calcium, strontium or barium
Method for producing hydrocarbons as described in Section 1. 4. Other metal components are alkali metals, alkaline earth metals, or Groups IB, IIB, IIIA, and III of the periodic table.
Group B, Group IVA, Group IVB, Group VA, Group VB, Group V
The method for producing a hydrocarbon according to claim 1, which is a metal of Group IB, Group VIIB, or Group VIII.