JPS5927836A - Production of hydrocarbon - Google Patents

Abstract

PURPOSE:To produce a higher hydrocarbon in high selectivity, by the catalytic reaction of CO with H2 using a catalyst containing ruthenium and thorium and having decreased sensitivity to the reaction temperature which is a weak point of conventional catalyst. CONSTITUTION:A higher hydrocarbon can be produced in high selectivity, by reacting CO with H2 in the presence of a catalyst containing 0.5-10wt% of ruthenium and 1.0-86.0wt% of thorium, e.g. obtained by supporting ruthenium and thorium on a carrier, supporting ruthenium on thorium oxide or a mixture of thorium oxide and other carrier, or homogeneously mixing ruthenium with thorium oxide. The catalyst is preferably prepared by conventional process such as coprecipitation process, evaporation to dryness, immersion, deposition, etc., and heat-treated at 400-500 deg.C for 1-5hr in reducing atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing hydrocarbons by catalytic reaction of carbon monoxide and hydrogen.

The production of hydrocarbons from a mixture of carbon monoxide and hydrogen by contacting the mixture with a catalyst at elevated temperature and pressure is a popular Fischer-Tropsch method for hydrocarbon synthesis. Are known. It is known that ruthenium-containing catalysts have relatively high activity as catalysts for the Fischer-Tropsch synthesis process, but in the relatively high reaction temperature range, a large amount of lower hydrocarbons such as methane are produced, making them difficult to use as high-grade hydrocarbons useful as automobile fuels, etc. There are drawbacks such as low hydrocarbon production. Furthermore, although the Fischer-Tropsch reaction is an exothermic reaction, ruthenium-containing catalysts are sensitive to the reaction temperature, making it difficult to control the reaction.

The method of the present invention provides an improved Fischer-Tropsch hydrocarbon synthesis method, and the inventors have found that when a catalyst containing ruthenium and thorium is used as a Fischer-Tropsch catalyst, higher carbonization can be achieved with high selectivity. Hydrogen, for example, higher hydrocarbons with a carbon number of 5 or more are produced, and the production of methane and lower hydrocarbons is reduced.Also, the drawbacks of ruthenium catalysts, which are said to be sensitive to reaction temperature, have been improved, and the production of hydrocarbons can be improved over a wide range of reaction temperature conditions. The present invention was completed by discovering the fact that the chain growth probability α value of the Schulz-Flory law, which is an index of product composition (distribution), exhibits a high value.

That is, the gist of the present invention resides in - a method for producing hydrocarbons by a catalytic reaction between carbon oxide and hydrogen, characterized in that the reaction is carried out using a catalyst containing ruthenium and thorium; .

The catalyst used in the process of the invention contains both ruthenium and thorium as essential components. Examples of catalysts include ruthenium and thorium supported on a support, ruthenium supported on thorium oxide or a mixture of thorium oxide and other supports, and homogeneous mixtures of ruthenium and thorium oxide. Examples of supports that can be used include alumina, silica, silica alumina, carbon,
Examples of metal oxides include alkali metals such as lithium,
Sodium, potassium, cesium, alkaline earth metals such as beryllium, argentium, calcium, strontium, barium, rare earth elements such as scandium, yttrium, lanthanum, cerium, uranium, Periodic Table IB, I [B, III, ■, v1 ■ Heavy elements such as copper, silver, zinc, gallium, indium, titanium,
There are oxides of metals such as zirconium, tin, lead, vanadium, antimony, bismuth, chromium, molybdenum, and tungsten. Preferred supports are alumina, silica, silica alumina, oxides of metals of Groups I, V and II of the periodic table, most preferably alumina, silica, silica alumina, oxides of vanadium, chromium. It is also preferable to use oxides and mixtures containing these as main oxides and other metal oxides. Examples of mixtures include Al2O3-ZrO2, Al2
O3-MgO1A1203-Ti02-20, Al2
O3-T102-CaO1AI203- ZnO, 5i
02-BeO, 5102-Mg0, 5i02-CaO
X5i02-La203.5i02-Zr02.5i0
2-Ga203, V2O5-C820, V2O5-A
gO-CuO.

V2O5-Ti 02- CuO, V2O5-Ti 0
2-MgO% V2O5-Ti 02-ZnO1V20
5- TLQz -Biz03, V2O5-ZrO2-
ccto XCr2O3-K2O, Cr203-Ago
-CuOXCr20B-Ti02-CuO, Cr2O3
-Ti02-8i02, etc. These supports increase the catalyst surface area without significantly inhibiting the catalytic properties of ruthenium and thorium, or work together with ruthenium and thorium to enhance the catalytic activity. It is also preferable to use these supports as a mixture with thorium oxide and to support ruthenium on the mixture. In addition, other poorly soluble substances that do not significantly inhibit the catalytic properties of ruthenium and thorium may be mixed with these carriers or the mixture of the carrier and thorium oxide. For this purpose, activators such as alkali metal carbonates, magnesium oxide, zinc oxide or mixtures thereof can also be added as supports or carriers. The carrier carrying ruthenium and thorium, the thorium oxide carrying ruthenium, or the mixture of thorium oxide and the carrier may be in any form such as powder, granules, spheres, or extruded shapes, and usually about 1 to 50%
0tf? /7, preferably about 10-300 m”/f,
Most preferably about 25 to 200 i/? can have a BET surface area of

The content of ruthenium in the catalyst is about 0.01 to 45% by weight,
Preferably about 0.1-20% by weight, most preferably about 0.5%
~10% by weight. The content of thorium in the catalyst is approximately 0.
01-99.9°9% by weight, preferably about 0.1-87.
0% by weight, most preferably about 1.0-86.0% by weight. If the ruthenium content in the catalyst is too low or does not contain ruthenium, almost no reaction will occur, and if the ruthenium content is too high, methane production will be significant or the chain growth probability α will rapidly decrease at high temperatures. Become. Furthermore, if the thorium content in the catalyst is too low or it does not contain thorium, the probability of chain growth in the high temperature range where methane production becomes significant will be low.

The catalyst containing ruthenium and thorium used in the present invention can be prepared by conventional catalyst preparation methods such as coprecipitation method, evaporation-drying method, immersion method, deposition method, and crosstalk method (details of which can be found in, for example, July 3, 1971).
Published on the 1st, edited by the Catalysis Society of Japan, “Catalyst Experiment Manual” 305
It is detailed in the bottom page of pages 340 to 340. ). Examples of ruthenium compounds used for catalyst preparation include ruthenium chloride, ruthenium nitrate,
There are salts such as ruthenium acetate, salts such as ammonia chloride and ruthenium Ru (NHa) sc12, which are soluble in water, and those soluble in organic solvents, such as ruthenium carbonyl (including ruthenium clusters) and ruthenium acetylacetonate. , insoluble thorium compounds such as thorium oxide in these aqueous or organic solvent solutions,
Ruthenium compounds can be supported by adsorption by soaking thorium metal, a carrier, or a mixture thereof, by ion exchange, by adding a precipitant, or by evaporating the solution to dryness. When a ruthenium compound is specifically supported, a thorium compound (described later) may be supported at the same time, or it may be supported before the thorium compound is supported or on phosphorus. ), the ruthenium compound obtained by adding a precipitant to these ruthenium compound solutions or evaporating to dryness is combined with a thorium compound prepared in the same manner (adding a carrier if necessary).
- Co-precipitate by adding a precipitant to a mixed solution of a ruthenium compound solution and a water-soluble or organic solvent-soluble thorium compound (adding a carrier or carrier precursor if necessary). It can be prepared by evaporating a mixed solution to dryness. Insoluble ruthenium compounds such as ruthenium metal powder and ruthenium oxide can also be mixed with a thorium compound (adding a carrier if necessary), suspended in water or an organic solvent, and then evaporated to dryness of the above ruthenium compound solution, adsorbed or deposited. It can be prepared according to the method described by.

Examples of thorium compounds that can be used for catalyst preparation include thorium chloride, logefide, thorium nitrate, thorium formate, and water-soluble compounds that dissolve in water or aqueous solvents, such as urea complex salts of these compounds. In the same manner as in the treatment of the ruthenium compound solution or suspension described above, the silica supported on a carrier, the silica that is kneaded together with the ruthenium compound, or co-precipitated or co-precipitated with the ruthenium compound,
It can be evaporated to dryness and incorporated into the catalyst. As mentioned above, insoluble metal thorium or thorium compounds such as thorium oxide and thorium metal powder are immersed in a solution or suspension of the ruthenium compound and the ruthenium compound is precipitated, precipitated, evaporated to dryness, etc. to remove thorium. It may also be deposited on the surface of a metal or thorium compound. The catalyst of the present invention may be composed only of ruthenium and thorium without a carrier, but it may also be one in which ruthenium and thorium are supported on a carrier, or in which ruthenium is supported on a mixture of a carrier and thorium or a thorium compound. However, a homogeneous mixture of ruthenium, thorium, and a carrier may also be used, and the preparation method thereof is as described above. The catalyst prepared as described above is usually dried and calcined with or without molding by a conventional method. Drying is carried out by holding the temperature at about 80 to 300°C, preferably about 100 to 150°C, for 1 minute to 10 hours, and baking is carried out, for example, by holding at about 30 to 300 degrees Celsius.
It can be carried out by holding the temperature at 0 to 700°C, preferably about 300 to 500°C, for 30 minutes to 24 hours.

Although the catalyst thus prepared may be subjected to the reaction as it is, it is preferably pretreated in a reducing atmosphere such as hydrogen gas. Pretreatment is performed at a temperature of about 30°C or more, preferably about 400°C or more.
The treatment is preferably carried out at 500°C under hydrogen pressure of normal pressure to increased pressure (approximately 300 atm or less) for about 1 minute to 8 hours, preferably about 1 to 5 hours. The pretreatment may be carried out in the Fischer-Tropsch reaction column prior to the reaction and does not need to be carried out in a separate step. By treatment with a reducing gas, ruthenium in the catalyst (partially converted into oxide during the calcination stage) -f! : Most of ruthenium is a simple metal, and 1 lium (most of it becomes an oxide during the firing stage) remains an oxide.

The reaction can be carried out under conventional Fischer-Tropsch reaction conditions. For example, the molar ratio of hydrogen to carbon monoxide (2/co molar ratio) is about 0.1 to 10, preferably about 0.5 to 4, and most preferably 0.5 to 2. Using a mixed gas of
°C preferably about 150-400 °C, most preferably about 200-400 °C
360°C, reaction pressure of about 1 to 300 atm, preferably about 10
~100 atm, most preferably about 10-60 atm
, the feed gas velocity per unit time per catalyst capacity (space velocity, SV) of about 100 to 50,000 hr-', especially about 30
The reaction can be carried out by bringing the raw material gas into contact with the above-mentioned catalyst under the conditions of 0 to 2000 hr-''.The reaction can be carried out using a flow-type fixed catalyst bed, a fluidized bed, a suspended bed, etc. In this case, the catalyst particle diameter is For example, about 1-5 mm each.

The reaction can be carried out with catalyst particles of about 0.5-2.5 mm and about 20-150 microns.

The hydrocarbons produced by the process of the present invention are mostly aliphatic hydrocarbon mixtures consisting of paraffins and olefins. Due to the use of a unique catalyst, the method of the present invention produces less methane than conventional typical ruthenium catalysts, and can produce higher hydrocarbons (e.g., carbon atoms of 5 or more) under a wide range of reaction temperature conditions. It has the effect of showing high selectivity.

The present invention will be explained below with reference to Examples.

Example 1 Catalyst A with ruthenium and thorium supported on γ-alumina
was prepared. That is, a solution of thorium nitrate-urea salt prepared by dissolving 10.26 F of thorium nitrate and 6.69 F of urea in 20 mL of an equal volume mixed solvent of water and ethyl alcohol, and ruthenium chloride RuCl3 .nH2O2,
282Y'e Two solutions dissolved in 40 mt of a mixed solvent of equal volume of water and ethyl alcohol were mixed, and 190v of γ-alumina dried with pure nitrogen at 450°C was immersed in the mixture, and evaporated to dryness. RuCl3-Th on γ-alumina
(N03)4'6(NH2)2Co'2H20
'I carried it. The product was dried at 110° C., then calcined in air at 450° C. for 5 hours in an electric furnace, then compressed into tablets, and further ground into 20 to 32 meshes to obtain catalyst A.

2 mt (1,0'?) of this catalyst was charged into a reaction vessel and pretreated at 300°C for 3 hours through hydrogen gas. Subsequently, the mixture was cooled to below the reaction temperature (100° C.) while passing hydrogen gas therethrough, and then a mixed gas of hydrogen and carbon monoxide was passed through the catalyst layer. The reaction conditions and product composition are shown in Table 1. Similar results were obtained with a catalyst using a mixture of γ-alumina and zirconium oxide instead of γ-alumina as a carrier.

As can be seen in Table 1, methane production was considerably greater than in Comparative Example 1, which will be described later, in which the reaction was carried out using Comparative Catalyst A', in which only ruthenium was supported on γ-alumina, similar to Catalyst A except that it did not contain thorium. It can be seen that the chain growth probability is low and has a high probability of chain growth, which is excellent for synthesizing higher hydrocarbons.

Comparative Example 1 Catalyst A', in which only ruthenium was supported on γ-alumina, was prepared in exactly the same manner as Catalyst A of Example 1, except that thorium was not contained. A reaction was carried out in the same manner as in Example 1 using this catalyst. The reaction conditions and results are shown in Table 1. As seen in Table 1, thorium-free catalyst A'
When the reaction was carried out using , more methane was produced than in Example 1, and less higher hydrocarbons were produced.

Example 2 Catalyst B, in which ruthenium and thorium were supported on silica, was prepared in exactly the same manner as in Example 1, except that silica was entirely used in place of γ-alumina. A reaction was carried out in the same manner as in Example 1 using this catalyst. The reaction conditions and results are shown in Table 1. Similar results were obtained with catalysts in which a mixture of silica and magnesium oxide was used instead of silica as a carrier, and a catalyst in which a mixture of silica and lanthanum oxide was used instead of silica.

Comparative Example 2 Catalyst B' was prepared in exactly the same manner as Catalyst B of Example 2, except that silica was used instead of γ-alumina and thorium was not contained. A reaction was carried out in exactly the same manner as in Example 1 using this catalyst. The reaction conditions and results are shown in Table 1.

Example 3 Powdered chromium oxide Cr2O3 was tablet-molded, pulverized into 20 to 32 meshes, and then vacuum-dried at 450°C to obtain carrier 8.
7.4f, thorium chloride The1.9.3451 and ruthenium chloride RuCl3.nH2O2, 284f were added to 40ml of water. immersed in a solution dissolved in After standing for one day and night, the solvent was removed using a water aspirator to support ruthenium and thorium on the chromium oxide. The product was dried in the open at 100-120°C and then heated in an electric furnace at 450°C in the air.
Catalyst C was prepared by calcining at ℃ for 3 hours.

A reaction was carried out in the same manner as in Example 1 using this catalyst.

The reaction conditions and results are shown in Table 2.In addition, catalysts using a mixture of chromium oxide and potassium oxide as a carrier instead of chromium oxide, and catalysts using a mixture of chromium oxide, titanium dioxide, and copper oxide as a carrier were also used. Similar results were obtained.0 Comparative Example 3 Catalyst C' was prepared in exactly the same manner as Catalyst C of Example 3 except that thorium was not contained. A reaction was carried out in the same manner as in Example 1 using this catalyst. The reaction conditions and results are shown in Table 2.

Example 4 Powdered vanadium pentoxide V2O5 after tableting 20-32
30. Or, thorium nitrate 9
．． 11f and 5.94f of urea were dissolved in 40 ml of an equal volume mixture of water and ethyl alcohol to form a thorium nitrate-urea salt. The solvent was removed using the water removal aspirator, and the product was dried in the air at 100 to 110°C, and then calcined in the air at 550°C for 3 hours in an electric furnace.

-3 of the obtained product 34.4f was placed in a flask,
A ruthenium carbonyl solution (1 mt, that is, a solution of 500 mt of ruthenium carbonyl Ru3(CO) dissolved in 500 mt of tetrahydrofuran, was injected into the system in 5 portions at 50°C under a nitrogen atmosphere. Ruthenium carbonyl was supported on the carrier by repeating the operation of distilling tetrahydrofuran by vacuum distillation each time.After cooling the obtained product with ice water, the atmosphere inside the system was gradually replaced with air. things in the air 1
It was dried at 00°C to prepare a catalyst.

A reaction was carried out in the same manner as in Example 1 using this catalyst.

The reaction conditions and results are shown in Table 2. Similar results were obtained with a catalyst using a mixture of vanadium pentoxide, titanium dioxide, and zinc oxide instead of vanadium pentoxide as a carrier.

Comparative Example 4 Catalyst D' was prepared in exactly the same manner as in Example 4 except that thorium was not contained. A reaction was carried out in the same manner as in Example 1 using this catalyst. The reaction conditions and results are shown in Table 2.

Example 5 Powdered thorium oxide ThO2 was compressed into 20 to 32 meshes, and then 87.4 tons of thorium oxide was vacuum-dried at 450°C, and ruthenium chloride RuC1B.nH2
It was immersed in a solution of O2,284f dissolved in 40 ml of water. After standing for one day and night, the solvent was removed using a water aspirator to support ruthenium on the thorium oxide.

The product was dried in the open at 100-120°C and then calcined in an electric furnace in air at 450°C for 3 hours to prepare catalyst E.
was prepared.

A reaction was carried out in the same manner as in Example 1 using this catalyst.

The reaction conditions and results are shown in Table 2.

As mentioned above, in the Fischer-Tropsch synthesis reaction, the catalyst containing ruthenium and thorium described in the above example produces less methane than the corresponding catalyst of the comparative example, which has the same composition except that it does not contain thorium. It can be seen that the chain growth probability α value can be maintained at a high value under a wide range of reaction temperature conditions, that the synthesis of higher hydrocarbons is excellent, and that a stable product composition can be obtained over a wide temperature range.

Claims (1)

[Claims] A method for producing hydrocarbons by a catalytic reaction between carbon monoxide and hydrogen, characterized in that the reaction is carried out using a catalyst containing ruthenium and thorium 0