JP2010005496A - Catalyst for fischer-tropsch synthesis and method of manufacturing hydrocarbons - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst for the Fischer-Tropsch synthesis (FT method) which achieves a high CO conversion rate, produces less gas ingredients, allows carrying out a FT synthesis reaction stably and is capable of improving the productivity of hydrocarbons and a method of manufacturing hydrocarbons using it. <P>SOLUTION: The catalyst for the Fischer-Tropsch synthesis consists of at least one metal having an activity on the Fischer-Tropsch synthesis and is supported in a support based on manganese carbonate. The method of manufacturing hydrocarbons using the catalyst is also provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a Fischer-Tropsch synthesis catalyst for producing hydrocarbons from a mixed gas containing hydrogen and carbon monoxide as main components (hereinafter referred to as “synthesis gas”), and hydrocarbons using the catalyst. It relates to the manufacturing method. More specifically, a catalyst mainly comprising manganese carbonate containing a metal having activity against the Fischer-Tropsch reaction (hereinafter referred to as “FT active metal”), and a synthetic gas brought into contact with the catalyst, naphtha, kerosene The present invention relates to a method for producing hydrocarbons such as diesel oil and wax.

  As methods for synthesizing hydrocarbons from synthesis gas, Fischer-Tropsch reaction (Fischer-Tropsch reaction), methanol synthesis reaction, C2 oxygen-containing (ethanol, acetaldehyde, etc.) synthesis reaction and the like are well known. The Fischer-Tropsch reaction is a catalyst using iron group elements such as iron, cobalt and nickel and platinum group elements such as ruthenium as active metals, the methanol synthesis reaction is a copper catalyst, and the C2 oxygen-containing synthesis reaction is a rhodium catalyst. It is known to proceed (see, for example, Non-Patent Document 1).

  By the way, in recent years, gas oil with low sulfur content has been desired from the viewpoint of the preservation of the air environment, and this trend is expected to become stronger in the future. In addition, from the viewpoint that crude oil resources are limited and from the viewpoint of energy security, the development of alternative fuels for oil is desired, and it is expected that this will become increasingly desirable in the future. As a technology that meets these demands, GTL (gas to liquids), a technology that synthesizes liquid fuels such as kerosene from natural gas (main component methane), which is said to have recoverable reserves equivalent to crude oil in terms of energy, is used. is there.

Since natural gas does not contain sulfur or is hydrogen sulfide (H ₂ S) or the like that is easy to desulfurize even if it contains, liquid fuel such as kerosene obtained has almost no sulfur in it. In addition, because of the advantage that it can be used for high-performance diesel fuel having a high cetane number, this GTL has been increasingly attracting attention in recent years.

  As part of the GTL, methods for producing hydrocarbons from synthesis gas by the Fischer-Tropsch reaction (hereinafter referred to as “FT reaction”) (hereinafter referred to as “FT method”) have been actively studied. In order to increase the yield of hydrocarbons in this FT method, a catalyst having excellent performance such as high production capacity of hydrocarbons, that is, high activity, little generation of gas components, and stable activity for a long time. Use is considered effective.

  Conventionally, various FT reaction catalysts have been proposed. For example, a catalyst in which an FT active metal species such as cobalt or iron is supported on a metal oxide carrier such as alumina, silica, silica-alumina, titania, or the like. It has been proposed (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3). Ruthenium catalysts such as a catalyst in which ruthenium is supported on a manganese oxide support and a catalyst in which a third component is further added to the ruthenium supported catalyst have been proposed as catalysts for high selectivity to olefins. (For example, see Patent Document 4 and Patent Document 5).

  These conventionally proposed catalysts show correspondingly excellent selectivity of olefins and corresponding catalytic activity in the FT method using the catalyst, but further improvement in catalytic activity is desired. In general, the higher the activity of the catalyst, the higher the productivity of the target product per catalyst weight, and the smaller the amount of catalyst used to obtain the same amount of target product, the smaller the reactor cost. And equipment costs can be reduced. Further, it is desired that the catalyst for the FT reaction has a low yield of gas components such as methane in the product and has a high yield of useful liquid hydrocarbons such as kerosene and light oil.

“C1 Chemistry”, Catalysis Society of Japan, Kodansha, April 1, 1984, page 25. US Pat. No. 5,733,839 US Pat. No. 5,545,674 European Patent No. 0167215 Japanese Patent Publication No. 3-70691 Japanese Patent Publication No. 3-70692

  In view of the above-described conventional situation, the present invention has a high CO conversion rate, a small amount of gas component generation, and a stable FT synthesis reaction in the FT method, thereby improving the productivity of hydrocarbons. It is an object of the present invention to provide a catalyst for FT synthesis that can be produced, and a method for producing hydrocarbons using the catalyst.

  The inventors of the present invention have intensively studied to achieve the above object. As a result, a catalyst in which an FT active metal is contained in a carrier mainly composed of manganese carbonate is a conventional metal oxide carrier. It was found that the activity was significantly higher than that of the catalyst used, and the generation of gas components was small, and the present invention was completed.

    The detailed mechanism of the improvement in the activity of the catalyst of the present invention and the decrease in the generation of gas has not been elucidated and is currently under intensive study, but is a carrier-based manganese carbonate that is inert to the FT reaction. Is presumed to act on the FT active metal species in some form to improve the activity and suppress the generation of gas.

That is, in order to achieve the above object, the present invention provides a catalyst for FT synthesis having the following constitution and a method for producing hydrocarbons using the catalyst.
1. A Fischer-Tropsch synthesis catalyst comprising a carrier comprising manganese carbonate as a main component and containing at least one metal having activity in a Fischer-Tropsch reaction.
2. 2. The Fischer-Tropsch synthesis catalyst as described in 1 above, wherein the metal having activity for the Fischer-Tropsch reaction is at least one selected from ruthenium and cobalt.
3. 3. The Fischer-Tropsch synthesis catalyst according to 2 above, wherein the ruthenium content is 0.5 to 5% by mass in terms of a catalyst, in terms of metal.
4). 3. The Fischer-Tropsch synthesis catalyst as described in 2 above, wherein the cobalt content is 5 to 40% by mass in terms of catalyst, in terms of metal.
5). A method for producing hydrocarbons, comprising bringing the gas mainly composed of hydrogen and carbon monoxide into contact with the Fischer-Tropsch synthesis catalyst according to any one of 1 to 4 above.

The catalyst using manganese carbonate as a carrier of the present invention has a higher CO conversion rate than conventional catalysts using alumina or silica as a carrier, and can reduce the production ratio of CH ₄ as a gas component. . Further, according to the present invention, a catalyst having high catalyst activity and high hydrocarbon productivity is provided, and effects such as catalyst cost and reactor size reduction are expected.

The present invention is described in detail below.
The Fischer-Tropsch synthesis catalyst of the present invention (hereinafter also referred to as “the catalyst of the present invention”) contains an FT active metal species in a carrier containing manganese carbonate as a main component (hereinafter also referred to as “manganese carbonate carrier”). It is something to be made. Hereinafter, the catalyst of the present invention and the preparation thereof to the production method of hydrocarbons using the same will be described in detail.

<Catalyst and its preparation>
As manganese carbonate which is the main component of the manganese carbonate support in the catalyst of the present invention, those produced and sold industrially can be used, and can also be produced by a conventionally known method. When manganese carbonate is obtained by a known method, it can be obtained by reacting a soluble manganese salt solution with ammonia carbonate or an alkali carbonate (for example, sodium carbonate). It can also be obtained by reaction of divalent manganese ions with carbonate ions or bicarbonate ions. Further, the manganese carbonate carrier may be composed only of manganese carbonate or may contain other components other than manganese carbonate as long as the effect of the intended manganese carbonate in the present invention is not inhibited. Examples of other components include inorganic oxides that are usually used as carriers, such as silica, alumina, silica-alumina, and the like. The content of the other components can be appropriately set as long as the desired effect of manganese carbonate in the present invention is not impaired, but generally 5 to 50% by mass is appropriate based on the carrier.

  Examples of the FT active metal species in the catalyst of the present invention include nickel, cobalt, iron, and ruthenium. Among them, ruthenium and cobalt are preferably selected as highly active metal species. Moreover, these metal seed | species can also be used independently and can also be used in mixture of 2 or more type.

  One method for preparing the catalyst of the present invention is to impregnate and support a FT active metal species on a manganese carbonate carrier as one of the methods for incorporating a FT active metal species into a manganese carbonate carrier. Hereinafter, this impregnation support will be described in the case where the FT active metal species is ruthenium or cobalt which is preferably used. This impregnation support can be performed by a normal impregnation support method. For example, it can be carried out by impregnating a manganese carbonate carrier with an aqueous solution of ruthenium salt or cobalt salt, and then drying and baking. At this time, when two or more metals are supported as FT active metal species, for example, an aqueous solution containing both a ruthenium salt and a cobalt salt may be prepared, impregnated with a ruthenium salt and a cobalt salt at the same time, and then dried and fired. Alternatively, each may be impregnated separately and then dried and fired. The method for impregnating and supporting the FT active metal species on the manganese carbonate support is not particularly limited.

  Examples of the ruthenium salt used for the impregnation support include water-soluble ruthenium salts such as ruthenium chloride, ruthenium nitrate, ruthenium acetate, and ruthenium hexaammonium chloride. Further, as the cobalt salt, cobalt chloride, cobalt nitrate, cobalt acetate, cobalt sulfate, and cobalt formate are preferably used. In addition, it is possible to use an organic solvent such as alcohol, ether or ketone instead of water as a solvent for the ruthenium salt or cobalt salt solution used for impregnation support. In this case, various organic compounds such as ruthenium salt and cobalt salt can be used. Select a salt that is soluble in the solvent.

  The ruthenium content in the catalyst of the present invention is preferably 0.5 to 5% by mass, more preferably 0.8 to 4.5% by mass, and particularly preferably 1 to 4% by mass in terms of catalyst and metal amount. is there. The amount of ruthenium supported is related to the number of active sites. By setting the supported amount of ruthenium to 0.5% by mass or more, the number of active sites is maintained and sufficient catalytic activity can be obtained. Further, by setting the amount of ruthenium supported to 5% by mass or less, it is possible to suppress a decrease in the dispersibility of ruthenium and the expression of ruthenium species that do not interact with the carrier component.

  Further, the content of cobalt is preferably 5 to 40% by mass, more preferably 5 to 35% by mass, and particularly preferably 5 to 30% by mass in terms of catalyst and metal amount. By making the cobalt content 5% by mass or more, a remarkable activity improvement effect as an active metal is recognized. Moreover, by setting it as 40 mass% or less, it can suppress agglomeration of cobalt under the drying process, the calcination process, and the reaction conditions when subjected to the FT reaction in preparing the catalyst. A decrease in specific surface area and pore volume can be suppressed, and furthermore, the amount of gas generated in the product in the FT reaction can be suppressed.

  After impregnating the manganese carbonate support with the FT active metal species, drying and firing are performed. In principle, the drying is performed to evaporate water, and the temperature is preferably 80 to 200 ° C, more preferably 100 to 150 ° C. By setting the drying temperature to 80 ° C. or higher, it is possible to sufficiently promote the transpiration of water, and if it is 200 ° C. or lower, it is possible to suppress the non-uniformity of the active metal component due to the rapid transpiration of water. Therefore, it is preferable.

  The firing temperature is preferably 150 to 300 ° C, more preferably 150 to 250 ° C. By setting the firing temperature within 300 ° C., it is possible to suppress decomposition of manganese carbonate as a carrier component into manganese oxide and carbon dioxide gas. In the present invention, manganese carbonate as a carrier component must be present in the form of a carbonate, and as specifically shown in Comparative Examples described later, manganese oxide does not provide the intended effect of the present invention. . In addition, since an appropriate temperature is required to activate the FT active metal species, the firing temperature is preferably within the above range. Moreover, although the processing time of drying or baking is not decided unconditionally by a processing amount, it is 1 to 10 hours normally. By setting the treatment time to 1 hour or longer, it is possible to reliably evaporate moisture and to suppress the activation of the FT active metal species from being diluted. Further, even if the treatment time exceeds 10 hours, the catalytic activity is almost the same as when the treatment time is 10 hours or less. Therefore, considering workability and productivity, 10 hours or less is preferable. The drying or baking treatment may be performed in the air, or may be an inert gas atmosphere such as nitrogen or helium, or a reducing gas atmosphere such as hydrogen, and is not particularly limited.

  In addition to the above impregnation support method, as a method for producing a catalyst in which an FT active metal species is contained in a manganese carbonate support of the present invention, an aqueous slurry containing manganese carbonate and an FT active metal species is prepared and sprayed. The method of drying is mentioned. The concentration of the slurry in this spray drying method is not particularly limited. However, if the slurry concentration is too low, precipitation of manganese carbonate occurs and the catalyst components are not uniform, which is not preferable. If the slurry concentration is too high, the slurry is fed. Therefore, an appropriate slurry concentration is selected. Further, at this time, silica sol or the like can be added as a binder component for the purpose of adjusting the concentration of the slurry, improving the moldability of the catalyst, and spheroidizing. The amount of the binder added at this time is preferably such that the catalyst activity is not lowered, and is generally selected in the range of 5 to 20% by mass.

  In addition, when a catalyst is produced by a spray drying method, manganese carbonate, an FT active metal species, and a binder component are simultaneously contained in the slurry and sprayed, or a slurry containing manganese carbonate and a binder is sprayed. There is a method of adding an FT active metal species in accordance with the impregnation supporting method. Moreover, it is preferable to implement the ventilation temperature in the spray-drying method within the drying and baking temperature in the above-mentioned impregnation supporting method.

  As another method for producing a catalyst in which an FT active metal is contained in a manganese carbonate carrier of the present invention, a manganese carbonate carrier or a carrier containing manganese carbonate and a binder prepared by spray drying is used as an aqueous solution of an FT active metal species. Or by adsorbing the active metal on the support (equilibrium adsorption method), or after immersing the support in an aqueous solution of FT active metal species, adding an alkaline precipitant solution such as ammonia water to the active metal on the support There is a method of precipitating (deposition method).

<Method for producing hydrocarbons>
In the method for producing hydrocarbons of the present invention, the catalyst of the present invention prepared as described above is subjected to the FT reaction, that is, the catalyst is brought into contact with synthesis gas mainly composed of hydrogen and carbon monoxide. Done. In the method for producing hydrocarbons of the present invention, the type of the reactor for the FT reaction includes a fixed bed, a fluidized bed, a suspension bed, a slurry bed, and the like, and is not particularly limited. Next, a method for producing the hydrocarbons of the present invention using a slurry bed will be described.

  When the method for producing the hydrocarbons of the present invention is performed in a slurry bed, the shape of the catalyst is preferably spherical, and the preferred range for the catalyst particle distribution is 1 μm or more and 150 μm or less, more preferably 5 μm or more and 120 μm or less, Most preferably, it is 10 μm or more and 110 μm or less. In the case of the slurry bed reaction mode, the catalyst is dispersed in a liquid hydrocarbon and used. Therefore, by setting the catalyst particle diameter to 1 μm or more, the outflow of the catalyst particles to the downstream side due to the particles being too fine. It is possible to suppress the decrease in the catalyst concentration in the reaction vessel and to suppress the downstream device from being damaged by the catalyst fine particles. In addition, by setting the catalyst particle diameter to 150 μm or less, it is possible to suppress a decrease in reaction activity due to non-uniform slurry without catalyst particles being dispersed throughout the reaction vessel. The spherical shape of the catalyst with no irregularities reduces the generation of fine particles due to catalyst cracking or pulverization due to contact between the catalysts or contact between the catalyst and the inner wall of the reactor in the reaction mode of the slurry bed. Therefore, it is preferable.

  In the method for producing hydrocarbons of the present invention, the catalyst of the present invention prepared as described above is subjected to a reduction treatment (activation treatment) in advance before being subjected to the FT reaction. By this reduction treatment, the catalyst is activated so as to exhibit a desired catalytic activity in the FT reaction. If this reduction treatment is not performed, the FT active metal species are not sufficiently reduced and do not exhibit the desired catalytic activity in the FT reaction.

  This reduction treatment is preferably performed by a method in which the catalyst is brought into contact with the reducing gas in a slurry state dispersed in liquid hydrocarbons, or a method in which the reducing gas is simply vented and brought into contact with the catalyst without using hydrocarbons. it can. As the liquid hydrocarbons in which the catalyst is dispersed in the former method, various liquids such as olefins, alkanes, alicyclic hydrocarbons, and aromatic hydrocarbons can be used as long as they are liquid under the processing conditions. Hydrocarbons can be used. Further, it may be a hydrocarbon containing a hetero element such as oxygen-containing or nitrogen-containing. The number of carbons of these hydrocarbons is not particularly limited as long as they are liquid under the processing conditions, but generally those of C6 to C40 are preferred, those of C9 to C40 are more preferred, and those of C9 to C35 are preferred. Is most preferred. If it is heavier than C6 hydrocarbons, the vapor pressure of the solvent does not become too high, and the range of processing conditions is not limited, which is preferable. Moreover, if it is lighter than C40 hydrocarbons, the solubility of the reducing gas does not decrease, and sufficient reduction treatment can be performed, which is preferable.

  In addition, the amount of catalyst dispersed in the hydrocarbons in the reduction treatment is appropriately 1 to 50% by mass, preferably 2 to 40% by mass, more preferably 3 to 30% by mass. If the amount of catalyst is 1% by mass or more, it is possible to prevent the reduction efficiency of the catalyst from being excessively lowered. Therefore, as a method for preventing a reduction in the reduction efficiency of the catalyst, there is a method for reducing the flow rate of the reducing gas. Thereby, it can be avoided that the dispersion of gas (reducing gas) -liquid (solvent) -solid (catalyst) is impaired. A catalyst amount of 50% by mass or less is preferable because the viscosity of the slurry in which the catalyst is dispersed in hydrocarbons does not become too high, the bubble dispersion is good, and the catalyst is sufficiently reduced.

  Moreover, 140-250 degreeC is preferable, the processing temperature of this reduction process has more preferable 150-200 degreeC, and its 160-200 degreeC is the most suitable. If it is 140 degreeC or more, FT active metal seed | species will fully be reduce | restored and sufficient reaction activity will be obtained. Moreover, if it is 250 degrees C or less, the danger that the decomposition | disassembly to manganese oxide of the manganese carbonate of a support component will advance and an activity fall will be avoided.

  For this reduction treatment, a reducing gas mainly containing hydrogen is preferably used. The reducing gas to be used may contain a certain amount of components other than hydrogen, for example, water vapor, nitrogen, rare gas, etc. within a range that does not hinder the reduction.

  Moreover, although this reduction process is influenced also by hydrogen partial pressure and process time with the said process temperature, 0.1-10 MPa is preferable, as for hydrogen partial pressure, 0.5-6 MPa is more preferable, and 1-5 MPa. Is most preferred. The reduction treatment time varies depending on the amount of catalyst, the amount of hydrogen flow, etc., but is generally preferably 0.1 to 72 hours, more preferably 1 to 48 hours, and most preferably 4 to 48 hours. If the treatment time is 0.1 hour or longer, it is possible to avoid insufficient activation of the catalyst. Moreover, if it is 72 hours or less, it is enough for the improvement of catalyst performance.

In the method for producing hydrocarbons of the present invention, the catalyst of the present invention reduced as described above is used for the FT reaction, that is, the hydrocarbon synthesis reaction.
The FT reaction in the method for producing hydrocarbons of the present invention is in a dispersed state in which a catalyst is dispersed in liquid hydrocarbons, and a synthesis gas comprising hydrogen and carbon monoxide is brought into contact with the dispersed catalyst. At this time, as the hydrocarbons in which the catalyst is dispersed, the same hydrocarbons used in the reduction treatment performed in advance can be used. That is, various hydrocarbons including olefins, alkanes, alicyclic hydrocarbons, aromatic hydrocarbons can be used as long as they are liquid under the reaction conditions, including oxygen, nitrogen, etc. The number of carbons does not need to be particularly limited, but is generally preferably C6 to C40, more preferably C9 to C40, and most preferably C9 to C35. preferable. If it is heavier than C6 hydrocarbons, the vapor pressure of the solvent does not become too high, and the reaction condition width is not limited, which is preferable. Moreover, if it is lighter than C40 hydrocarbons, the solubility of the raw material synthesis gas will not decrease, and a decrease in reaction activity can be avoided. In the reduction treatment performed in advance, in the case where a method in which the catalyst is dispersed in liquid hydrocarbons is employed, the liquid hydrocarbons used in the reduction treatment can be used as they are in this FT reaction.

  The amount of the catalyst dispersed in the hydrocarbons in the FT reaction is preferably 1 to 50% by mass, more preferably 2 to 40% by mass, and most preferably 3 to 30% by mass. If the amount of catalyst is 1% by mass or more, it is possible to avoid a lack of catalyst activity. In addition, if the activity is insufficient, in order to make up for the lack of activity, the aeration amount of the synthesis gas is decreased, and the gas (synthesis gas) -liquid (solvent) -solid (catalyst) dispersion is caused by the decrease in the aeration amount of the synthesis gas. Is damaged. Further, if the amount of catalyst is 50% by mass or less, it is possible to avoid that the viscosity of the slurry in which the catalyst is dispersed in hydrocarbons becomes too high, resulting in poor bubble dispersion and insufficient reaction activity. .

The synthesis gas used for the FT reaction only needs to contain hydrogen and carbon monoxide as main components, and other components that do not interfere with the FT reaction may be mixed. Further, since the rate (k) of the FT reaction depends on the first order of the hydrogen partial pressure, it is desirable that the partial pressure ratio of hydrogen and carbon monoxide (H ₂ / CO molar ratio) is 0.6 or more. Since this reaction is a reaction accompanied by volume reduction, the higher the total value of the partial pressure of hydrogen and carbon monoxide, the better. The upper limit of the partial pressure ratio of hydrogen and carbon monoxide is not particularly limited, but the practical range of the partial pressure ratio is preferably 0.6 to 2.7, more preferably 0.8 to 2.5, and particularly Preferably it is 1-2. If this partial pressure ratio is 0.6 or more, it is possible to prevent the yield of produced hydrocarbons from decreasing, and if this partial pressure ratio is 2.7 or less, gas is produced in the produced hydrocarbons. The tendency to increase the components and light components can be suppressed.

  Another component that does not interfere with the FT reaction that may be mixed in the synthesis gas includes carbon dioxide. In the method for producing hydrocarbons of the present invention, synthesis gas mixed with carbon dioxide obtained by a reforming reaction of natural gas or petroleum products can be used without any problem. Also, other components that do not interfere with the FT reaction other than carbon dioxide may be mixed. For example, methane or steam obtained from steam reforming reaction or autothermal reforming reaction of natural gas, petroleum products, etc. Or a synthesis gas containing partially oxidized nitrogen or the like may be used. The carbon dioxide can also be positively added to synthesis gas that does not contain carbon dioxide. In carrying out the method for producing hydrocarbons of the present invention, a synthesis gas containing carbon dioxide obtained by reforming natural gas or petroleum products by a self-thermal reforming method or a steam reforming method, If the FT reaction is used as it is without decarboxylation to remove carbon dioxide, the equipment construction cost and operation cost required for the decarboxylation treatment can be reduced, and the hydrocarbons obtained by the FT reaction can be produced. Cost can be reduced.

  In the method for producing hydrocarbons of the present invention, the total pressure of the synthesis gas (mixed gas) subjected to the FT reaction (total value of partial pressures of all components) is preferably 0.5 to 10 MPa, and 0.7 to 7 MPa. More preferably, 0.8-5 MPa is still more preferable. If this total pressure is 0.5 MPa or more, chain growth is sufficient, and it is possible to prevent the yield of gasoline, kerosene, wax, and the like from decreasing. In terms of equilibrium, the higher the partial pressure of hydrogen and carbon monoxide, the more advantageous. However, if the total pressure is 10 MPa or less, the plant construction cost increases and the operation is increased by increasing the size of the compressor required for compression. The disadvantages from the industrial point of view, such as rising costs, can be suppressed accordingly.

Generally, in this FT reaction, if the H ₂ / CO molar ratio of the synthesis gas is the same, the lower the reaction temperature, the higher the chain growth probability and the C5 + selectivity (for products having 5 or more carbon atoms in the FT-reactive organism). Ratio) increases, but CO conversion decreases. Conversely, if the reaction temperature is increased, the chain growth probability and C5 + selectivity are lowered, but the CO conversion is increased. In addition, the higher the H ₂ / CO ratio, the higher the CO conversion rate, the lower the chain growth probability and C5 + selectivity, and vice versa when the H ₂ / CO ratio is low. The effect of these factors on the reaction varies depending on the type of catalyst used, but in the method using the catalyst of the present invention, the reaction temperature is suitably 200 to 350 ° C, and 210 to 310 ° C. Preferably, 220 to 290 ° C is more preferable. The CO conversion rate is defined by the following formula.
[CO conversion rate]
CO conversion rate = [(number of moles of CO in raw material gas per unit time) − (number of moles of CO in outlet gas per unit time)] / number of moles of CO in raw material gas per unit time × 100

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not limited to these Examples.

In the following Examples, CO analysis was performed by a thermal conductivity gas chromatograph (TCD-GC) using Active Carbon (60 / 80mesh) as a separation column. Incidentally, the raw material gas used was 25 vol% added syngas as an internal standard (mixed gas of _{H 2} and CO) to Ar. Qualitative and quantitative analysis was performed by comparing the peak position and peak area of CO with Ar. The chemical component of the catalyst was identified by ICP (CQM-10000P, manufactured by Shimadzu Corporation).

Further, CH ₄ selectivity was calculated by the following equation.
CH ₄ selectivity (%) = (CH ₄ moles in outlet gas per unit time) / {(number of CO moles in raw material gas per unit time) − (number of CO moles in outlet gas per unit time) )} × 100

Example 1
Manganese carbonate (II) n hydrate manufactured by Wako Pure Chemical Industries was used as manganese carbonate.
After drying at 150 ° C. for 5 hours in advance, 4.925 g of manganese carbonate was weighed and impregnated with an aqueous solution in which 0.184 g of ruthenium chloride (Ru Assay 40.79% by mass made by Kojima Chemical) was dissolved in 3.0 g of water. After standing for a period of time, it was dried in air at 80 ° C. for 3 hours and then calcined at 150 ° C. for 3 hours to obtain Catalyst A.
As a result of structural analysis of the catalyst A by X-ray diffraction, manganese maintained manganese carbonate. Moreover, as a result of conducting the chemical composition analysis of the catalyst A by ICP, ruthenium was 1.5 mass% in metal conversion.

Catalyst A (2.4 g) was charged into a reactor having an internal volume of 100 ml together with 40 ml of normal hexadecane (slurry concentration: 7.2 wt%) as a dispersion medium, a hydrogen partial pressure of 0.9 MPa · G, a temperature of 170 ° C., and a flow rate of 100 (STP). ) Hydrogen was brought into contact with catalyst A at ml / min (STP: standard temperature and pressure) and reduced for 3 hours. After the reduction, the FT reaction was carried out at a temperature of 260 ° C. and a H ₂ + CO pressure of 0.9 MPa · G by switching to a synthesis gas having an H ₂ / CO ratio of about 2 (including about 25 vol. Ar).
W / F (weight / flow) [g · hr / mol] was about 11 g · hr / mol. The CO conversion 20 hours after the start of the FT reaction was about 51.5%, the CH ₄ selectivity was about 10.5%, and the CO conversion after 100 hours was about 50.2%.

Example 2
Catalyst B was obtained in the same manner as in Example 1 except that the amounts of manganese carbonate and ruthenium chloride were adjusted so that the content of ruthenium was 3.0% by mass.
As a result of analyzing the chemical composition of the catalyst B by ICP, ruthenium was 2.9% by mass in terms of metal. This catalyst B was subjected to the FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 70.9%, the CH ₄ selectivity was 11.5%, and the CO conversion after 100 hours was about 70.3%.

Example 3
As manganese carbonate, the same manganese carbonate (II) n hydrate manufactured by Wako Pure Chemical Industries, Ltd. as in Example 1 was used.
After drying at 150 ° C. for 5 hours in advance, 4.5 g of manganese carbonate is weighed, and 2.463 g of cobalt nitrate (Co (NO ₃ ) ₂ · 6H ₂ O manufactured by Wako Pure Chemical Industries) is dissolved in 3.0 g of water. The obtained aqueous solution was impregnated and allowed to stand for 1 hour, dried in air at 80 ° C. for 3 hours, and then calcined at 200 ° C. for 3 hours to obtain Catalyst C.
As a result of structural analysis of the catalyst C by X-ray diffraction, manganese maintained manganese carbonate. Moreover, as a result of conducting the chemical composition analysis of the catalyst C in ICP, cobalt was 10.1 mass% in metal conversion. This catalyst C was subjected to the FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 62.4%, the CH ₄ selectivity was about 11.8%, and the CO conversion after 100 hours was about 60.1%.

Example 4
Catalyst D was obtained in the same manner as in Example 3, except that the amounts of manganese carbonate and cobalt nitrate were adjusted so that the cobalt content was 30% by mass.
As a result of conducting the chemical composition analysis of the catalyst D by ICP, cobalt was 30.2 mass% in metal conversion. This catalyst D was subjected to FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 68.2%, the CH ₄ selectivity was about 20.8%, and the CO conversion after 100 hours was about 67.1%.

Example 5
As manganese carbonate, the same manganese carbonate (II) n hydrate manufactured by Wako Pure Chemical Industries, Ltd. as in Example 1 was used.
After drying at 150 ° C. for 5 hours in advance, 4.425 g of manganese carbonate was weighed, and 0.184 g of ruthenium chloride (Ru Assay 40.79% by mass made by Kojima Chemical) and cobalt nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 3.0 g of water. After impregnating an aqueous solution in which 2.463 g of Co (NO ₃ ) ₂ · 6H ₂ O) was dissolved, the mixture was allowed to stand for 1 hour, dried in air at 80 ° C. for 3 hours, and then calcined at 200 ° C. for 3 hours to obtain catalyst E. Obtained.
As a result of structural analysis of the catalyst E by X-ray diffraction, manganese maintained manganese carbonate. Moreover, as a result of conducting the chemical composition analysis of the catalyst E in ICP, ruthenium was 1.5 mass% in metal conversion, and cobalt was 10.1 mass% in metal conversion. This catalyst E was subjected to FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 76.7%, the CH ₄ selectivity was about 35.4%, and the CO conversion after 100 hours was about 76.2%.

Comparative Example 1
Catalyst F was obtained in the same manner as in Example 1 except that manganese oxide (III) (Mn ₂ O ₃ ) manufactured by Wako Pure Chemical Industries, Ltd. was used instead of manganese carbonate.
As a result of structural analysis of the catalyst F by X-ray diffraction, manganese was Mn ₂ O ₃ . As a result of analyzing the chemical composition of the catalyst F by ICP, ruthenium was 1.6% by mass in terms of metal. This catalyst F was subjected to FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 31.0%, the CH ₄ selectivity was about 8.5%, and the CO conversion after 100 hours was about 23.1%.

Comparative Example 2
Catalyst G was obtained in the same manner as in Example 1 except that manganese oxide (II) (MnO) manufactured by Wako Pure Chemical Industries, Ltd. was used instead of manganese carbonate.
As a result of structural analysis of the catalyst G by X-ray diffraction, manganese was MnO. As a result of analyzing the chemical composition of the catalyst G by ICP, ruthenium was 1.5% by mass in terms of metal. This catalyst G was subjected to the FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 11.2%, the CH ₄ selectivity was about 7.2%, and the CO conversion after 100 hours was about 9.3%.

Comparative Example 3
After sufficiently drying spherical silica (Q-30) manufactured by Fuji Silysia Chemical instead of manganese carbonate, 4.925 g was weighed, and then ruthenium chloride in 6.06 g of water (Ru Assay 40.79% by mass manufactured by Kojima Chemical). An aqueous solution in which 0.184 g was dissolved was impregnated and left for 1 hour, then dried in air at 80 ° C. for 3 hours, and then calcined at 200 ° C. for 3 hours to obtain Catalyst H.
As a result of analyzing the chemical composition of the catalyst H by ICP, ruthenium was 1.6% by mass in terms of metal. This catalyst H was subjected to FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 15.7%, the CH ₄ selectivity was about 16.6%, and the CO conversion after 100 hours was about 14.8%.

Comparative Example 4
Aluminum oxide powder (manufactured by Pural SB, Condea) was sufficiently dried in place of manganese carbonate, and 4.925 g was weighed. Then, 4.43 g of water was mixed with ruthenium chloride (Ru Assay 40.79% by mass, manufactured by Kojima Chemical). An aqueous solution in which 184 g was dissolved was impregnated, left for 1 hour, dried in air at 80 ° C. for 3 hours, and then calcined at 200 ° C. for 3 hours to obtain Catalyst I.
As a result of analyzing the chemical composition of the catalyst I by ICP, ruthenium was 1.5% by mass in terms of metal. This catalyst I was subjected to the FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 30.2%, the CH ₄ selectivity was about 21.0%, and the CO conversion after 100 hours was about 18.9%.

Comparative Example 5
After spherical silica (Q-30) manufactured by Fuji Silysia Chemical Co., Ltd. was sufficiently dried instead of manganese carbonate, 4.5 g was weighed, and cobalt nitrate (Co (NO ₃ manufactured by Wako Pure Chemical Industries) was added to 5.54 g of water. ₂ ) 6H ₂ O) An aqueous solution in which 2.463 g was dissolved was impregnated and allowed to stand for 1 hour, dried in air at 80 ° C. for 3 hours, and then calcined at 200 ° C. for 3 hours to obtain Catalyst J.
As a result of analyzing the chemical composition of the catalyst J by ICP, cobalt was 10.2% by mass in terms of metal. This catalyst J was subjected to the FT reaction in the same manner as in Example 1. The CO conversion after 20 hours from the start of the FT reaction was about 36.2%, the CH ₄ selectivity was about 43.5%, and the CO conversion after 100 hours was about 30.7%.

Comparative Example 6
Catalyst K was obtained in the same manner as in Comparative Example 5 except that the amounts of spherical silica, water and cobalt nitrate were adjusted so that the cobalt content was 30% by mass.
As a result of analyzing the chemical composition of the catalyst K by ICP, cobalt was 30.1% by mass in terms of metal. This catalyst K was subjected to the FT reaction in the same manner as in Example 1. The CO conversion 20 hours after the start of the FT reaction was about 61.6%, the CH ₄ selectivity was about 50.7%, and the CO conversion after 100 hours was about 57.5%.

The experimental results of Examples 1 to 5 and Comparative Examples 1 to 6 are shown in Tables 1 and 2. From Tables 1 and 2, the catalyst using the manganese carbonate carrier of the present invention has a higher CO conversion rate than the conventional catalyst using alumina or silica as a carrier, and the production ratio of CH ₄ which is a gas component. Is clearly low. Furthermore, it turns out that the performance of the catalyst of this invention is exhibited stably for a long time. Further, it can be seen that such an effect of the present invention is not observed when a manganese oxide carrier is used, but is manifested by using a manganese carbonate carrier.

Claims (5)

  A Fischer-Tropsch synthesis catalyst comprising a carrier comprising manganese carbonate as a main component and containing at least one metal having activity in a Fischer-Tropsch reaction.   The catalyst for Fischer-Tropsch synthesis according to claim 1, wherein the metal having activity for the Fischer-Tropsch reaction is at least one selected from ruthenium and cobalt.   3. The Fischer-Tropsch synthesis catalyst according to claim 2, wherein the ruthenium content is 0.5 to 5% by mass in terms of catalyst and metal.   The catalyst for Fischer-Tropsch synthesis according to claim 2, wherein the cobalt content is 5 to 40% by mass in terms of a catalyst, in terms of metal.   A method for producing hydrocarbons, comprising bringing the gas mainly composed of hydrogen and carbon monoxide into contact with the Fischer-Tropsch synthesis catalyst according to any one of claims 1 to 4.