Catalyst for producing high calorific value fuel gas, method for producing the same, and method for producing high calorific value fuel gas

Abstract

To provide a catalyst for producing high calorific value fuel gas, enabling production of a fuel gas composed mainly of methane and further comprising ethane, propane, and butane, from a mixed gas comprising hydrogen and at least one of carbon monoxide and carbon dioxide.SOLUTION: A catalyst for producing high calorific value fuel gas comprising iron, cobalt, and rhenium supported on a carrier mainly composed of activated alumina, wherein the amount of the supported cobalt is 5.0 pts.mass or more and 20 pts.mass or less relative to 100 pts.mass of the carrier, the amount of the supported iron is 0.10 pt.mass or more and 5.0 pts.mass or less relative to 100 pts.mass of the carrier, and the amount of the supported rhenium is 1.0 pt.mass or more and 3.0 pts.mass or less relative to 100 pts.mass of the carrier.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a technology for producing a high-heat-value fuel gas having a higher heat value per unit volume than methane, from a mixed gas containing hydrogen and at least one of carbon monoxide or carbon dioxide, and more specifically, to a technology for producing a fuel gas containing methane as a main component and also containing ethane, propane, and butane. [Background technology]

[0002] In recent years, from the perspective of combating global warming, attention has been focused on carbon-neutral fuels, which do not substantially increase the concentration of carbon dioxide in the atmosphere even when burned.

[0003] Methane can be obtained by capturing carbon dioxide from exhaust gases generated by industrial processes and thermal power plants, electrolyzing the gas using electricity from renewable energy sources such as solar and wind power, and then reacting the resulting hydrogen on a methanation catalyst. Alternatively, electrolyzing a mixed gas consisting of carbon dioxide and water vapor using a solid oxide electrolysis cell (SOEC) produces a gas (synthesis gas) primarily composed of hydrogen and carbon monoxide, which can then be reacted on a methanation catalyst to produce methane. Methane obtained by these methods can be considered a carbon-neutral fuel that does not contribute to global warming, as no additional carbon dioxide is produced when it is burned.

[0004] The methanation reaction (formula 1) in which carbon monoxide and hydrogen are reacted to obtain methane, and the methanation reaction (formula 2) in which carbon dioxide and hydrogen are reacted to obtain methane, are both known. CO+3H2→ CH4+H2O (Formula 1) CO2+4H2→ CH4+2H2O (Formula 2)

[0005] Methanation reactions have long been used to remove carbon monoxide and carbon dioxide from hydrogen for ammonia synthesis, and catalysts supporting Ni, Ru, etc. are known to exhibit high activity (Non-Patent Documents 1 and 2).

[0006] Methanation, in which carbon monoxide or carbon dioxide is reacted with hydrogen to produce methane, is an industrially established technology (e.g., Non-Patent Document 3). However, there are still challenges to be overcome in obtaining a fuel gas of a quality that can be used as a source of city gas.

[0007] Natural gas is generally used as a raw material for city gas, and is composed primarily of methane, with small amounts of ethane, propane, and butane. The composition of natural gas varies depending on the gas field, and its calorific value is not constant. Fluctuations in calorific value can change the combustibility of the gas, potentially causing unstable performance in gas-consuming equipment. Therefore, in gas production in Japan's city gas industry, liquefied petroleum gas (LPG), which is primarily composed of propane or butane, is added to the raw material natural gas (often vaporized liquefied natural gas) to adjust the calorific value to fall within a certain range. In Japan, the calorific value of 1 m3 of natural gas at standard conditions (0°C, 101.325 kPa) is 3 In many cases, city gas with a calorific value (higher heating value) of 45MJ per liter is produced and supplied.

[0008] Under normal reaction conditions, the only hydrocarbon produced by the methanation reaction is methane, and does not contain hydrocarbons with two or more carbon atoms, such as ethane or propane. The calorific value of methane is 39.8 MJ / m 3 Therefore, it is 45MJ / m, which is the general value for city gas. 3 In order to adjust the calorific value, it is necessary to add a large amount of LPG, which is uneconomical. In addition, LPG, which can be considered carbon neutral, has limited distribution and is difficult to obtain.

[0009] Various techniques have been investigated for producing high-heat-value fuel gases containing methane as the main component and saturated hydrocarbons other than methane as minor components by reacting carbon oxides (carbon monoxide and carbon dioxide) with hydrogen.

[0010] Patent Document 1 discloses a catalyst for producing high-calorie gas, characterized in that it comprises a silica or alumina support carrying an iron-group metal as a catalytic substrate in combination with manganese oxide and a platinum-group metal. It is stated that cobalt and iron are particularly preferred as iron-group metals, but the experimental results disclosed are limited to a catalyst in which three components, ruthenium, cobalt, and manganese, are supported on a silica or alumina support. In the preparation of the catalyst described in Patent Document 1, the ruthenium supporting step involves exposure to a high-concentration ammonia-containing gas, which raises concerns about the economic viability of the catalyst preparation step.

[0011] Patent Document 2 discloses a method for producing a high-calorie hydrocarbon mixed gas from a mixed gas containing carbon monoxide and hydrogen in the presence of a catalyst, characterized by using a mixed catalyst comprising: [A] a first catalyst containing an active component composed of an iron group metal and manganese oxide, or an iron group metal, manganese oxide, and a platinum group metal, and a metal oxide as a support; and [B] a second catalyst composed of a pentasil-type zeolite ion-exchanged with hydrogen and / or a Group VIII metal. While the catalyst described in Patent Document 2 is shown to produce C2-C4 hydrocarbons in high yield, the hydrocarbon synthesis reaction by hydrogenation of carbon monoxide and carbon dioxide is accompanied by the generation of water vapor, and the catalyst is exposed to a high-concentration water vapor atmosphere, raising concerns about the stability over time of the second catalyst composed of pentasil-type zeolite under such conditions.

[0012] Patent Document 3 discloses a catalyst for producing high-calorie gas in which ruthenium and an iron group element are supported on a metal oxide support, with a ruthenium dispersion of 20% or more. When this catalyst is used, the cooperative action of ruthenium and the iron group element allows for a calorific value of 45 MJ / m, which can be supplied as city gas, at a relatively low temperature under conditions of high carbon monoxide conversion. 3 The above shows that a fuel gas containing methane as the main component and C2-C4 hydrocarbons can be obtained.

[0013] However, to ensure sufficient economic viability for a carbon-neutral city gas production process, a catalyst is needed that can show a high conversion rate to hydrocarbons at lower temperatures and that can be easily prepared using inexpensive constituent materials. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] Japanese Patent Application Publication No. 59-46133 [Patent Document 2] Japanese Patent Application Publication No. 63-241099 [Patent Document 3] Japanese Patent Application Laid-Open No. 2010-149109 [Non-patent literature]

[0015] [Non-Patent Document 1] Chemical Process Compilation, edited by the Society of Chemical Engineers, 1970, p.153 [Non-patent document 2] Catalysis Society of Japan, Catalyst Handbook, 2008, p.535 [Non-patent document 3] Kuroda, Journal of the Fuel Association, Vol. 63, No. 9, 1984, p. 790 Summary of the Invention [Problem to be solved by the invention]

[0016] In view of the above problems, the problem that the present invention aims to solve is to provide a catalyst for producing a high calorific value fuel gas that produces a fuel gas containing methane as a main component and also ethane, propane, and butane, from a mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen at a relatively low temperature, and to provide an energy-saving and highly efficient method for producing a high calorific value fuel gas using such a catalyst for producing a high calorific value fuel gas. [Means for solving the problem]

[0017] The catalyst for producing a high calorific value fuel gas according to the present invention is characterized in that it contains iron, cobalt, and rhenium supported on a support primarily composed of activated alumina, the amount of cobalt supported being 5.0 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the support, the amount of iron supported being 0.10 parts by mass or more and 5.0 parts by mass or less per 100 parts by mass of the support, and the amount of rhenium supported being 1.0 parts by mass or more and 3.0 parts by mass or less per 100 parts by mass of the support.

[0018] By using the catalyst having this characteristic configuration, when producing fuel gas from a mixed gas containing hydrogen and at least one of carbon monoxide or carbon dioxide, it is possible to obtain fuel gas with a high conversion rate to hydrocarbons and a high calorific value even at a low reaction temperature, without using expensive constituent materials such as precious metals such as platinum and ruthenium.

[0019] A further characteristic feature of the catalyst for producing a high calorific value fuel gas according to the present invention is that the support contains κ-type alumina.

[0020] By incorporating κ-type alumina into activated alumina, which is the main component of a catalyst for producing high calorific value fuel gas, it is possible to increase the production efficiency of high calorific value fuel gas and also to increase the proportion of relatively heavy hydrocarbons among the hydrocarbons contained in the product obtained by the production of high calorific value fuel gas.

[0021] A further characteristic feature of the catalyst for producing a high calorific value fuel gas according to the present invention is that the catalyst contains 1.0 to 5.0 parts by mass of nickel per 100 parts by mass of the support.

[0022] By supporting nickel on the catalyst for producing a high calorific value fuel gas, it is possible to increase the proportion of light hydrocarbons contained in the product obtained from the production of a high calorific value fuel gas.

[0023] A further characteristic feature of the catalyst for producing a high calorific value fuel gas according to the present invention is that the catalyst contains 1.0 to 5.0 parts by mass of nickel per 100 parts by mass of the support.

[0024] By supporting nickel on the catalyst for producing a high calorific value fuel gas, it is possible to increase the proportion of light hydrocarbons contained in the product obtained from the production of a high calorific value fuel gas.

[0025] A further characteristic feature of the catalyst for producing a high calorific value fuel gas according to the present invention is that the support is a molded body having a particle size of 1.0 mm or more and 20 mm or less.

[0026] According to this characteristic configuration, the catalyst for producing a high calorific value fuel gas has high activity and sufficient strength for industrial use, making it possible to produce a high calorific value fuel gas in an economically advantageous manner.

[0027] A characteristic feature of the method for producing a catalyst for producing a high calorific value fuel gas according to the present invention is that it is a method for producing a catalyst for producing a high calorific value fuel gas, containing cobalt, iron, and rhenium supported on a carrier mainly composed of activated alumina, and includes an impregnation step of impregnating the carrier with an aqueous solution containing water-soluble compounds of cobalt, iron, and rhenium to obtain an impregnated body, a drying step of drying the impregnated body to obtain a dried body, and a calcination step of calcining the dried body in air at a temperature of 350°C to 500°C.

[0028] According to this method, it is possible to produce a catalyst for producing a high calorific value fuel gas using relatively inexpensive constituent materials, which has a high conversion rate to hydrocarbons even at a relatively low temperature, and which is capable of producing a fuel gas with a high calorific value.

[0029] A further characteristic feature of the method for producing a catalyst for producing a high calorific value fuel gas according to the present invention is that the support contains κ-type alumina.

[0030] By incorporating κ-type alumina into activated alumina, which is the main component of a catalyst for producing high calorific value fuel gas, it is possible to increase the production efficiency of high calorific value fuel gas and also to increase the proportion of relatively heavy hydrocarbons among the hydrocarbons contained in the product obtained by the production of high calorific value fuel gas.

[0031] A further characteristic feature of the method for producing a catalyst for producing a high calorific value fuel gas according to the present invention is that the catalyst contains nickel.

[0032] By supporting nickel on the catalyst for producing a high calorific value fuel gas, it is possible to increase the proportion of light hydrocarbons contained in the product obtained from the production of a high calorific value fuel gas.

[0033] A further characteristic feature of the method for producing a catalyst for producing a high calorific value fuel gas according to the present invention is that the catalyst contains nickel.

[0034] By supporting nickel on the catalyst for producing a high calorific value fuel gas, it is possible to increase the proportion of light hydrocarbons contained in the product obtained from the production of a high calorific value fuel gas.

[0035] A further characteristic feature of the method for producing a catalyst for producing a high calorific value fuel gas according to the present invention is that the support is a molded body having a particle size of 1.0 mm or more and 20 mm or less.

[0036] According to this characteristic configuration, the catalyst for producing a high calorific value fuel gas has high activity and sufficient strength for industrial use, making it possible to produce a high calorific value fuel gas in an economically advantageous manner.

[0037] The method for producing a high calorific value fuel gas according to the present invention is characterized in that a mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen is brought into contact with a catalyst comprising activated alumina carrying cobalt, rhenium, and iron at a temperature of 225°C to 325°C to obtain a gas containing methane as the main component and also containing ethane, propane, and butane.

[0038] According to this method, a fuel gas with a high calorific value can be produced from a mixed gas containing hydrogen and at least one of carbon monoxide or carbon dioxide with a high conversion rate even at a low temperature using a catalyst made of relatively inexpensive constituent materials, making it possible to economically advantageously produce a fuel gas with a high calorific value.

[0039] The method for producing a high calorific value fuel gas according to the present invention is characterized in that a mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen is brought into contact with a catalyst comprising activated alumina carrying cobalt, rhenium, nickel, and iron at a temperature of 225°C to 325°C to obtain a gas containing methane as the main component and also containing ethane, propane, and butane.

[0040] According to this method, a fuel gas with a high calorific value can be produced from a mixed gas containing hydrogen and at least one of carbon monoxide or carbon dioxide with a high conversion rate even at a low temperature using a catalyst made of relatively inexpensive constituent materials, making it possible to economically advantageously produce a fuel gas with a high calorific value. DETAILED DESCRIPTION OF THE INVENTION

[0041] Hereinafter, embodiments of a catalyst for producing a high calorific value fuel gas, a method for producing the same, and a method for producing a high calorific value fuel gas according to the present invention will be described.

[0042] The main component of the catalyst for producing high calorific value fuel gas according to the embodiment of the present invention is activated alumina, which is a transition alumina typified by γ-type and κ-type. Activated alumina undergoes a phase transition to α-type by, for example, calcination at a high temperature of 1100°C or higher. However, α-type alumina has a small specific surface area and is therefore unable to support the active metal in a highly dispersed state, making it unsuitable as a support for the molded catalyst for preparing the high calorific value component of the present invention.

[0043] The catalyst for producing a high calorific value fuel gas of the present invention comprises cobalt, rhenium, nickel and iron supported on activated alumina.

[0044] In the catalyst for producing a high calorific value fuel gas of the present invention, cobalt acts as the main active metal responsible for the function of synthesizing hydrocarbons through the hydrogenation reaction of carbon monoxide and carbon dioxide.

[0045] The amount of cobalt supported should be 5.0 to 20 parts by mass, more preferably 7.0 to 15 parts by mass, per 100 parts by mass of activated alumina. If the amount is less than 5.0 parts by mass, sufficient catalytic activity cannot be obtained, resulting in a low conversion rate of carbon monoxide or carbon dioxide. The post-reaction gas contains large amounts of carbon monoxide, carbon dioxide, and hydrogen, which require expensive separation, potentially reducing the economic viability of fuel gas production. Furthermore, if the amount of cobalt supported is more than 20 parts by mass per 100 parts by mass of activated alumina, catalytic activity commensurate with the supported amount cannot be obtained, potentially resulting in economic disadvantages.

[0046] Furthermore, in the catalyst for producing high calorific value fuel gas according to an embodiment of the present invention, rhenium functions as a promoter and contributes to improving the reducibility of cobalt. If the amount of rhenium supported is less than 0.1 parts by mass per 100 parts by mass of activated alumina, the cobalt exists as an oxide in the catalyst, and the reduction reaction of carbon monoxide and carbon dioxide does not proceed sufficiently. On the other hand, the effect of rhenium as a promoter is sufficiently obtained if the amount supported is 1.0 part by mass or more per 100 parts by mass of activated alumina. Furthermore, if the amount of rhenium supported is more than 3.0 parts by mass per 100 parts by mass of activated alumina, catalytic activity commensurate with the amount supported may not be obtained, which may be economically disadvantageous.

[0047] The catalyst for producing a high calorific value fuel gas of the present invention may also contain nickel, which functions as a promoter to supplement the function of cobalt in synthesizing hydrocarbons through the hydrogenation reaction of carbon monoxide and carbon dioxide, thereby improving the methane yield. When nickel is contained, the amount of nickel supported is 1.0 to 5.0 parts by mass, more preferably 3.0 to 5.0 parts by mass, per 100 parts by mass of activated alumina.

[0048] Furthermore, in the catalyst for producing a high calorific value fuel gas of the present invention, iron acts as a catalytic active site that promotes carbon chain growth. If the amount of supported iron is less than 0.1 parts by mass per 100 parts by mass of activated alumina, carbon chain growth will not proceed, resulting in a decrease in the amounts of ethane, propane, and butane produced, and a decrease in the calorific value of the resulting fuel gas. On the other hand, if the amount of supported iron is more than 5.0 parts by mass per 100 parts by mass of activated alumina, the hydrocarbon synthesis activity of cobalt, nickel, and rhenium will be reduced, resulting in a decrease in the carbon monoxide or carbon dioxide conversion rate. From these perspectives, the amount of supported iron is preferably 0.10 to 5.0 parts by mass per 100 parts by mass of activated alumina.

[0049] Furthermore, if the total amount of cobalt, rhenium, nickel, and iron loaded is greater than 25 parts by mass per 100 parts by mass of activated alumina, the degree of dispersion of the loaded cobalt, rhenium, nickel, and iron will be low, and in addition, gas diffusivity in the activated alumina carrier will be reduced, which may result in an inability to obtain activity commensurate with the loaded amounts. From the above viewpoints, it is preferable that the amount of cobalt loaded is 5.0 to 20 parts by mass per 100 parts by mass of activated alumina, the amount of rhenium loaded is 1.0 to 3.0 parts by mass, the amount of nickel loaded is 0.0 to 5.0 parts by mass per 100 parts by mass of activated alumina, and the amount of iron loaded is 0.10 to 5.0 parts by mass per 100 parts by mass of activated alumina.

[0050] The catalyst for producing a high calorific value fuel gas according to an embodiment of the present invention may be of any shape, but is usually a molded body having a particle size of 1 to 20 mm. Here, a particle size of 1 to 20 mm means that if the molded body is spherical, its diameter is in the range of 1 to 20 mm, if the molded body is cylindrical, its diameter and length are in the range of 1 to 20 mm, and if the molded body has another shape, its hydrodynamic equivalent diameter is in the range of 1 to 20 mm.

[0051] If the particle size of the molded bodies is smaller than 1 mm, the pressure loss when the reaction gas flows through a reaction vessel filled with the molded catalyst bodies increases, which may reduce the economic viability of the high calorific value fuel gas production process.On the other hand, if the particle size is larger than 20 mm, the geometric surface area of ​​the molded bodies becomes relatively small, which may reduce the catalytic activity.

[0052] In addition, in order for cobalt to function sufficiently as an active site for the hydrogenation reaction of carbon monoxide or carbon dioxide, it is preferable that the cobalt, which is responsible for catalytic activity, and the rhenium, which promotes its reducibility, are distributed in close proximity in the molded catalyst body.

[0053] A method for producing a catalyst for producing a high calorific value fuel gas according to an embodiment of the present invention includes an impregnation step of impregnating an activated alumina molded body with an aqueous solution containing water-soluble compounds of cobalt, rhenium, and iron to obtain a cobalt-rhenium-iron impregnated body, a drying step of drying the impregnated body to obtain a dried body, and a calcination step of calcining the dried body in air at a temperature of 350°C to 500°C to obtain activated alumina having cobalt, rhenium, and iron dispersed thereon.

[0054] According to this method, it is possible to produce a catalyst for producing a high calorific value fuel gas using relatively inexpensive constituent materials, which has a high conversion rate to hydrocarbons even at a relatively low temperature, and which is capable of producing a fuel gas with a high calorific value.

[0055] A method for producing a catalyst for producing a high calorific value fuel gas according to an embodiment of the present invention includes an impregnation step of impregnating activated alumina with an aqueous solution containing water-soluble compounds of cobalt, rhenium, nickel, and iron to obtain a cobalt-rhenium-iron-nickel impregnated body, a drying step of drying the impregnated body to obtain a dried body, and a calcination step of calcining the dried body in air at a temperature of 350°C to 500°C to obtain activated alumina having cobalt, rhenium, iron, and nickel dispersed thereon.

[0056] According to this method, it is possible to produce a catalyst for producing a high calorific value fuel gas using relatively inexpensive constituent materials, which has a high conversion rate to hydrocarbons even at a relatively low temperature, and which is capable of producing a fuel gas with a high calorific value.

[0057] Activated alumina is a transition alumina, typically γ-type or κ-type, and is generally molded into a spherical or cylindrical shape with a diameter of 1.0 mm to 20 mm, although the size and shape are not critical. Such molded bodies are obtained by rolling granulation or tableting. Examples of water-soluble cobalt compounds that can be used include cobalt nitrate (Co(NO3)2) and cobalt acetate (Co(CH3COO)2).

[0058] Examples of water-soluble compounds of rhenium that can be used include perrhenic acid (HReO4) and ammonium perrhenate (NH4ReO4).

[0059] An example of a water-soluble nickel compound that can be used is nickel nitrate (Ni(NO3)2).

[0060] Examples of water-soluble iron compounds that can be used include iron (III) nitrate (Fe(NO3)3), iron (II) nitrate (Fe(NO3)2), iron (III) chloride (FeCl3), and iron (II) chloride (FeCl2).

[0061] The temperature and time of the cobalt-rhenium-iron-nickel impregnation step are not particularly limited, but it can be carried out, for example, at room temperature for about 1 to 20 hours.

[0062] There are no particular restrictions on the temperature and time of the drying step, but it can be carried out, for example, at 80°C to 200°C for about 1 to 20 hours.

[0063] If the temperature of the calcination step is too low, the decomposition of the cobalt, rhenium, iron, and nickel compounds may be insufficient, and if it is too high, the sintering of the activated alumina may proceed, reducing its specific surface area. Therefore, the temperature is preferably 300°C or higher and 600°C or lower, and more preferably 350°C or higher and 500°C or lower.

[0064] If the calcination time is too short, there is a risk that the decomposition of the cobalt, rhenium, iron, and nickel compounds will be insufficient, whereas if it is too long, it will be economically disadvantageous and there is also a risk that the specific surface area of ​​the activated alumina will decrease. Therefore, it is preferable to set the calcination time to about 1 hour or more and 20 hours or less.

[0065] The gas flowing in the firing step may be air, but oxygen or nitrogen may be added as necessary to adjust the oxygen concentration.

[0066] In a method for producing a high calorific value fuel gas according to an embodiment of the present invention, a mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen is contacted with a catalyst comprising activated alumina supported with cobalt, rhenium, iron, and nickel compounds at a temperature of 225°C to 325°C to obtain a gas containing methane as the main component and also containing ethane, propane, and butane.

[0067] The ratio of carbon monoxide or carbon dioxide to hydrogen in a mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen is as follows: if only carbon monoxide is contained as the carbon oxide, the hydrogen / carbon monoxide molar ratio is 2.5 to 3; if only carbon dioxide is contained as the carbon oxide, the hydrogen / carbon monoxide molar ratio is approximately 3.5 to 4; and if both carbon monoxide and carbon dioxide are contained as carbon oxides, the hydrogen / (carbon monoxide + carbon dioxide) molar ratio is appropriately selected within the range of 2.5 to 4. If the hydrogen / carbon monoxide (or carbon dioxide) molar ratio is higher than the above, a large amount of hydrogen will remain in the produced fuel gas, which may be economically disadvantageous. In addition, the production of C2-C4 hydrocarbons will be more difficult, which may reduce the calorific value of the fuel gas. On the other hand, if the hydrogen / carbon monoxide (or carbon dioxide) molar ratio is lower than the above, a large amount of carbon monoxide and carbon dioxide will remain in the produced fuel gas, which may be economically disadvantageous.

[0068] The catalyst for producing a high calorific value fuel gas according to an embodiment of the present invention has high activity in synthesizing hydrocarbons from carbon monoxide and carbon dioxide, but its activity is insufficient at temperatures below 225° C. Furthermore, at temperatures above 325° C., the rate of methane production becomes extremely fast relative to the production of C2-C4 hydrocarbons, which increases the proportion of methane in the fuel gas and may result in a decrease in the calorific value of the fuel gas.

[0069] Therefore, the temperature at which the mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen is brought into contact with the catalyst for producing a high calorific value fuel gas is set to 225°C or higher and 325°C or lower.

[0070] The reaction of carbon monoxide and carbon dioxide with hydrogen to obtain hydrocarbons generates a relatively large amount of heat, so if the reaction is carried out adiabatically, the temperature of the catalyst layer may rise by approximately 200 to 400°C. If the temperature of the catalyst layer rises, the supported cobalt, rhenium, nickel, and iron may aggregate, reducing catalytic activity, and the activated alumina may sinter and undergo a phase change, reducing the strength of the catalyst. In addition, the generated C2-C4 hydrocarbons may decompose on the catalyst, reducing the calorific value of the fuel gas.

[0071] The method for producing a high calorific value fuel gas according to an embodiment of the present invention is preferably carried out using a heat exchange reactor, while removing the heat of reaction and maintaining the catalyst temperature in the range of 225°C to 325°C. It is preferable that the entire catalyst layer be maintained in the range of 225°C to 325°C, but there is no significant problem if part of the catalyst layer is outside this range. However, parts of the catalyst layer whose temperature is below 225°C do not contribute to the progress of the reaction, which may be economically disadvantageous. In addition, if the catalyst layer temperature significantly exceeds 325°C, the decomposition of the C2-C4 hydrocarbons may progress.

[0072] The shape of the heat exchange reactor may be a shell-and-tube type or a plate type reactor, and when a shell-and-tube type reactor is employed, the catalyst may be packed on either the shell side or the tube side.

[0073] In the method for producing a high calorific value fuel gas of the present invention, a portion of the reactor outlet gas may be recycled to the reactor inlet, or the gas obtained after condensing and separating hydrocarbons having 5 or more carbon atoms from the produced fuel gas may be recycled to the reactor inlet, or hydrogen and / or carbon dioxide may be separated from the produced fuel gas by membrane separation and recycled to the reactor inlet.

[0074] The reaction pressure in the method for producing a high calorific value fuel gas according to an embodiment of the present invention is not particularly limited, but is carried out under an absolute pressure of 0.3 MPa to 3 MPa, preferably 0.3 MPa to 1 MPa.

[0075] In this application, high calorific value fuel gas is defined as a gas with a volume of 1 m3 under standard conditions (0°C, 101.325 kPa). 3 This refers to gas with a calorific value (higher calorific value) of 41MJ or more per unit.

[0076] (Example) The present invention will be described in more detail below based on examples and comparative examples, but the present invention is not limited to the following examples.

[0077] Example 1 9.0 g of iron nitrate nonahydrate (Fe(NO3)3·9H2O), 12.3 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), and 1.08 g of ammonium perrhenate (NH4ReO4) were dissolved in 13 g of pure water to obtain an aqueous solution containing iron compounds, cobalt compounds, and rhenium compounds. Activated alumina (Sumitomo Chemical Co., Ltd., KHA-24, 2.0-4.0 mm spherical molded body, BET specific surface area 162 m) was used. 2 25.0 g of cobalt-rhenium-iron-supported alumina (cobalt-rhenium-iron / g) was immersed in the aqueous solution for 15 hours, evaporated to dryness on a hot plate, and then dried in a dryer at 90°C for 1 hour and then at 115°C for 1 hour to obtain a dried body. This dried body was loaded into an electric furnace, heated from room temperature to 360°C over 3 hours while passing air through it, and calcined by holding at 360°C for 6 hours. Thereafter, it was allowed to cool to room temperature over 3 hours to obtain cobalt-rhenium-iron-supported alumina A.

[0078] Example 2 An aqueous solution containing cobalt, rhenium, and iron compounds was prepared by dissolving 12.3 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), 1.08 g of ammonium perrhenate (NH4ReO4), and 9.04 g of iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O) in 10 g of purified water. 25.1 g of activated alumina (Sumitomo Chemical, KHA-24; 2-4 mm spherical bodies were calcined in an electric furnace at 1045°C for 6 hours under airflow, resulting in the presence of kappa-alumina.) was immersed in the solution for 15 hours, evaporated to dryness on a hot plate, and then dried in an oven at 90°C for 1 hour and then at 115°C for 1 hour. This dried body was loaded into an electric furnace, and while passing air through it, the temperature was raised from room temperature to 360°C over 3 hours, and then calcined by maintaining it at 360°C for 6 hours. Thereafter, it was allowed to cool to room temperature over 3 hours, and cobalt-rhenium-iron-supported alumina B was obtained.

[0079] Example 3 An aqueous solution containing cobalt, rhenium, and iron compounds was prepared by dissolving 17.89 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), 1.08 g of ammonium perrhenate (NH4ReO4), and 0.90 g of iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O) in 10 g of purified water. 25.1 g of activated alumina (Sumitomo Chemical, KHA-24; 2-4 mm spherical bodies were calcined in an electric furnace at 1045°C for 6 hours under airflow, resulting in the presence of kappa-alumina.) was immersed in the solution for 15 hours, evaporated to dryness on a hot plate, and then dried in an oven at 90°C for 1 hour and then at 115°C for 1 hour. This dried body was loaded into an electric furnace, and while passing air through it, the temperature was raised from room temperature to 360°C over 3 hours, and then calcined by holding at 360°C for 6 hours. Thereafter, it was allowed to cool to room temperature over 3 hours, and cobalt-rhenium-iron-supported alumina C was obtained.

[0080] Example 4 An aqueous solution containing cobalt, rhenium, iron, and nickel compounds was prepared by dissolving 8.64 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), 1.08 g of ammonium perrhenate (NH4ReO4), 9.04 g of iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O), and 3.72 g of nickel nitrate hexahydrate (Ni(NO3)2·6H2O) in 8 g of purified water. 25.1 g of activated alumina (Sumitomo Chemical, KHA-24, 2-4 mm spherical compacts) was immersed in the solution for 15 hours, evaporated to dryness on a hot plate, and then dried in an oven at 90°C for 1 hour and then at 115°C for 1 hour. This dried body was loaded into an electric furnace, and while air was flowing through it, the temperature was raised from room temperature to 360°C over 3 hours, and then calcined by maintaining it at 360°C for 6 hours. Thereafter, it was allowed to cool to room temperature over 3 hours, and cobalt-rhenium-iron-nickel supported alumina D was obtained.

[0081] Example 5 An aqueous solution containing cobalt, rhenium, iron, and nickel compounds was prepared by dissolving 8.64 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), 1.08 g of ammonium perrhenate (NH4ReO4), 9.04 g of iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O), and 3.72 g of nickel nitrate hexahydrate (Ni(NO3)2·6H2O) in 8 g of purified water. 25.1 g of activated alumina (Sumitomo Chemical, KHA-24; 2–4 mm spherical bodies were calcined in an electric furnace at 1045°C for 6 hours under airflow, resulting in the presence of kappa-alumina.) was immersed in the solution for 15 hours, evaporated to dryness on a hot plate, and then dried in an oven at 90°C for 1 hour and then at 115°C for 1 hour. This dried body was loaded into an electric furnace, and while air was flowing through it, the temperature was raised from room temperature to 360°C over 3 hours, and then calcined by holding at 360°C for 6 hours. Thereafter, it was allowed to cool to room temperature over 3 hours, and cobalt-rhenium-iron-supported alumina E was obtained.

[0082] (Comparative Example 1) 18.5 g of cobalt nitrate hexahydrate (Co(NO) 6H O) and 0.72 g of ammonium perrhenate (NHReO) were dissolved in 17 g of pure water to obtain an aqueous solution containing cobalt and rhenium compounds. Activated alumina (Sumitomo Chemical, KHA-24, 2.0-4.0 mm spherical molded body, BET specific surface area 162 m) was used. 2 25.0 g of cobalt-rhenium-supported alumina (cobalt-rhenium / g) was immersed in the aqueous solution for 15 hours, evaporated to dryness on a hot plate, and then dried for 1 hour in a dryer maintained at 120°C to obtain a dried body. This dried body was loaded into an electric furnace, heated from room temperature to 360°C over 3 hours while air was circulated, and calcined by maintaining at 360°C for 6 hours. Thereafter, the material was allowed to cool to room temperature over 3 hours to obtain cobalt-rhenium-supported alumina F.

[0083] (Comparative Example 2) An aqueous solution containing cobalt and rhenium compounds was prepared by dissolving 12.3 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O) and 0.72 g of ammonium perrhenate (NH4ReO4) in 9 g of purified water. 25.0 g of activated alumina (Sumitomo Chemical, KHA-24; 2–4 mm spherical compacts were calcined in an electric furnace at 1045°C for 6 hours with air flow, so the activated alumina contains kappa-alumina). This solution was then immersed and impregnated for 15 hours. The mixture was evaporated to dryness on a hot plate, then dried in an oven at 90°C for 1 hour and then at 115°C for 1 hour. This dried product was then loaded into an electric furnace and calcined at 360°C for 6 hours with air flow. Thereafter, the mixture was allowed to cool to room temperature over 3 hours, and cobalt-rhenium-supported alumina G was obtained.

[0084] (Comparative Example 3) 6.2 g of nickel nitrate hexahydrate (Ni(NO3)2·6H2O), 12.3 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), and 1.08 g of ammonium perrhenate (NH4ReO4) were dissolved in 13 g of pure water to obtain an aqueous solution containing nickel, cobalt, and rhenium compounds. Activated alumina (Sumitomo Chemical Co., Ltd., KHA-24, 2.0-4.0 mm spherical molded body, BET specific surface area 162 m) was used. 2 25.1 g of cobalt-rhenium-nickel-supported alumina (H) was immersed in the aqueous solution for 15 hours, evaporated to dryness on a hot plate, and then dried in a dryer at 90°C for 1 hour and then at 115°C for 1 hour to obtain a dried body. This dried body was loaded into an electric furnace, heated from room temperature to 360°C over 3 hours while passing air through it, and calcined by holding at 360°C for 6 hours. It was then allowed to cool to room temperature over 3 hours to obtain cobalt-rhenium-nickel-supported alumina H.

[0085] Comparative Example 4 An aqueous solution containing cobalt, rhenium, iron, and nickel compounds was prepared by dissolving 12.1 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), 1.51 g of ammonium perrhenate (NH4ReO4), 12.65 g of iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O), and 5.20 g of nickel nitrate hexahydrate (Ni(NO3)2·6H2O) in 13 g of pure water. A zirconia (manufactured by Daiichi Kigenso Kagaku Kogyo Co., Ltd., RSC-HP, cylindrical molded body 3.0 mm diameter x 3.0 mm height, BET specific surface area 45.8 m) was used. 2 35.1 g of zirconia (cobalt-rhenium-iron-nickel supported zirconia I) was immersed in the aqueous solution for 15 hours, evaporated to dryness on a hot plate, and then dried in a dryer maintained at 120°C for 3 hours to obtain a dried body. This dried body was loaded into an electric furnace, heated from room temperature to 360°C over 3 hours while passing air through it, and calcined by maintaining it at 360°C for 6 hours. Thereafter, it was allowed to cool to room temperature over 3 hours to obtain cobalt-rhenium-iron-nickel supported zirconia I.

[0086] (Comparative Example 5) An aqueous solution containing cobalt, rhenium, iron, and nickel compounds was prepared by dissolving 8.64 g of cobalt nitrate hexahydrate (Co(NO3)2·6H2O), 1.51 g of ammonium perrhenate (NH4ReO4), 12.65 g of iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O), and 8.67 g of nickel nitrate hexahydrate (Ni(NO3)2·6H2O) in 13 g of pure water. Activated zirconia (manufactured by Daiichi Kigenso Kagaku Kogyo Co., Ltd., RSC-HP, cylindrical molded body 3.0 mm diameter x 3.0 mm height, BET specific surface area 45.8 m) was used. 2 35.2 g of zirconia (cobalt-rhenium-iron-nickel supported zirconia) was immersed in the aqueous solution for 15 hours, evaporated to dryness on a hot plate, and then dried in a dryer maintained at 120°C for 3 hours to obtain a dried body. This dried body was loaded into an electric furnace, heated from room temperature to 360°C over 3 hours while air was circulating, and calcined by maintaining at 360°C for 6 hours. Thereafter, the mixture was allowed to cool to room temperature over 3 hours to obtain cobalt-rhenium-iron-nickel supported zirconia J.

[0087] (Catalyst analysis results) The BET specific surface area was measured for each of catalysts A, B, C, D, E, F, and G. The results are shown in Table 1. [Table 1]

[0088] <Method for measuring BET specific surface area> The BET specific surface area of ​​each sample before and after high-temperature calcination was measured by the BET single-point method using the nitrogen adsorption amount at liquid nitrogen temperature under the condition of a relative pressure (P / P0) of 0.3.

[0089] (Evaluation results of hydrocarbon synthesis activity) The hydrocarbon synthesis activity was evaluated for each of Catalysts A, B, C, D, E, F, and G. The results are shown in Table 2. [Table 2]

[0090] <Method for evaluating hydrocarbon synthesis activity> A stainless steel reaction tube (inner diameter 16 mm) was filled with 5 mL of catalyst to form a catalyst layer. Then, while heating the catalyst layer to maintain its temperature at 400°C, a reducing gas consisting of a mixture of nitrogen gas and 10% hydrogen gas (by volume) was circulated at a rate of 12.0 L / h (volume under standard conditions of 0°C and 101.325 kPa, hereinafter the same) to carry out a reduction treatment for 1 hour. After the reduction treatment, the catalyst bed temperature was raised to 225°C, and a gas mixture with a volume ratio of carbon monoxide, carbon dioxide, hydrogen, and nitrogen (CO:CO:H:N = 3:1:13:15) was passed through the catalyst bed at a flow rate of 20 L / h. The concentrations of carbon monoxide, carbon dioxide, hydrogen, nitrogen, and hydrocarbons with carbon numbers of 1 to 6 (methane to hexane) in the catalyst bed outlet gas were analyzed using a gas chromatograph (Shimadzu GC-2014B, equipped with TCD and FID detectors). Subsequently, while the test gas was still flowing, the catalyst bed temperature was raised in 25°C increments up to 325°C, and the catalyst bed outlet gas was similarly analyzed by gas chromatograph. The reaction pressure was 0.7 MPa (absolute pressure). Note that nitrogen was not essential for the reaction; it was added to mitigate temperature rise and facilitate control of the catalyst bed temperature. From the analysis results of the catalyst bed outlet gas, the hydrocarbon yield, C1-C4 hydrocarbon yield, and calorific value were calculated using the following formula. The C1-C4 hydrocarbon yield indicates the proportion of carbon monoxide supplied to the catalyst bed that was converted to C1-C4 hydrocarbons. The C1-C4 hydrocarbon calorific value was calculated based on the calorific value of the C1-C4 hydrocarbon components that can be used as a town gas feedstock, assuming that hydrocarbons of C5 or higher are separated from the produced gas by condensation, and that hydrogen, carbon monoxide, and carbon dioxide are separated by methods such as membrane separation. Note that C2-C4 hydrocarbons may contain very small amounts of unsaturated hydrocarbons (e.g., ethylene). However, if necessary, these can be easily converted to saturated hydrocarbons (e.g., ethane) by passing them through a hydrogenation catalyst and hydrogenating them with unreacted hydrogen. Therefore, the calorific value of unsaturated hydrocarbons (e.g., ethylene) was calculated using the calorific value of the corresponding saturated hydrocarbon (e.g., ethane). Hydrocarbon yield (%) = (carbon content of hydrocarbons in the gas at the outlet of the catalyst layer) / (carbon content of all gases in the gas at the outlet of the catalyst layer) C1-C4 hydrocarbon yield (%) = (carbon content of C1-C4 hydrocarbons in the gas at the outlet of the catalyst layer) / (carbon content of all gases at the outlet of the catalyst layer) C1-C4 hydrocarbon calorific value (MJ / m 3 )=(39.8m+69.7e+99.1p+128.5b) / (m+e+p+b) where m, e, p, and b are the volumetric contents of methane, ethane, propane, and butane, respectively, in the gas at the catalyst layer outlet.

[0091] Evaluation of Examples and Comparative Examples With the catalyst of Example 1, the C1-C4 hydrocarbon yield was 56.6% at a catalyst bed temperature of 225°C, but reached 71.3% at 250°C, 63.1% at 275°C, and 51.4% at 300°C. The C1-C4 hydrocarbon calorific value was 46.9 MJ / Nm at a catalyst bed temperature of 225°C. 3 , 45.4MJ / Nm at 250℃ 3 , 46.6MJ / Nm at 275℃ 3 , 48.8MJ / Nm at 300℃ 3 From the above results, it can be seen that when carbon monoxide, carbon dioxide, and hydrogen are reacted using the catalyst of Example 1 at temperatures between 225°C and 300°C, C1-C4 hydrocarbons can be obtained in a yield of 50% or more, and the calorific value is 45 MJ / m 3 It can be seen that a high-heat-value fuel gas that can be easily used as city gas can be obtained, exceeding the calorific value of 1000 kJ / L.

[0092] With the catalyst of Example 2, the C1-C4 hydrocarbon yield was 9.1% at a catalyst bed temperature of 225°C, but reached 59.0% at 250°C, 54.2% at 275°C, and 42.1% at 300°C. The C1-C4 hydrocarbon calorific value was 53.8 MJ / Nm at a catalyst bed temperature of 225°C. 3 , 48.9MJ / Nm at 250℃ 3 , 50.4MJ / Nm at 275℃ 3 , 50.2MJ / Nm at 300℃ 3From the above results, when carbon monoxide, carbon dioxide, and hydrogen were reacted using the catalyst of Example 2 at 225°C to 300°C, the yield of C1-C4 hydrocarbons decreased compared to when the catalyst of Example 1 was used, but the calorific value of C1-C4 hydrocarbons increased compared to Example 1. This tendency is presumed to be due to the fact that the calcination of the activated alumina support increased the average pore size in the support, improving gas diffusivity.

[0093] With the catalyst of Example 3, the C1-C4 hydrocarbon yield was 90.7% at a catalyst bed temperature of 225°C, but reached 89.8% at 250°C, 83.8% at 275°C, and 73.2% at 300°C. The C1-C4 hydrocarbon calorific value was 42.9 MJ / Nm at a catalyst bed temperature of 225°C. 3 , 43.0MJ / Nm at 250℃ 3 , 43.5MJ / Nm at 275℃ 3 , 43.4MJ / Nm at 300℃ 3 From the above results, it can be seen that when carbon monoxide, carbon dioxide, and hydrogen are reacted at 225°C to 300°C using the catalyst of Example 3 in which the amounts of cobalt and iron supported are adjusted, a relatively high C1-C4 hydrocarbon yield of 42.9 MJ / Nm is obtained compared to the cases in which the catalysts of Examples 1 and 2 are used. 3 It is possible to synthesize gases of the above types.

[0094] With the catalyst of Example 4, the C1-C4 hydrocarbon yield was 73.7% at a catalyst bed temperature of 225°C, but reached 81.7% at 250°C, 83.7% at 275°C, and 82.5% at 300°C. The C1-C4 hydrocarbon calorific value was 42.9 MJ / Nm at a catalyst bed temperature of 225°C. 3 , 41.2MJ / Nm at 250℃ 3 , 41.3MJ / Nm at 275℃ 3 , 41.7MJ / Nm at 300℃ 3 From the above results, it was found that when catalyst D, which contains cobalt-rhenium-nickel-iron with nickel added as a support component, was used to react carbon monoxide, carbon dioxide and hydrogen at temperatures between 225 and 300°C, the yield of C1-C4 hydrocarbons was 70% or more, and the calorific value of C1-C4 hydrocarbons was 41 MJ / Nm 3The calorific value of C1-C4 hydrocarbons was smaller than in Examples 1, 2, and 3, suggesting that the hydrogenation activity of carbon monoxide and carbon dioxide was improved by supporting nickel, possibly resulting in an increased methane yield.

[0095] With the catalyst of Example 5, the C1-C4 hydrocarbon yield was 76.8% at a catalyst bed temperature of 225°C, but reached 80.0% at 250°C, 72.2% at 275°C, and 65.7% at 300°C. The C1-C4 hydrocarbon calorific value was 44.5 MJ / Nm at a catalyst bed temperature of 225°C. 3 , 44.1MJ / Nm at 250℃ 3 , 46.0MJ / Nm at 275℃ 3 , 46.7MJ / Nm at 300℃ 3 From the above results, it was found that when catalyst E, which is made of cobalt-rhenium-nickel-iron supported on an inorganic compound carrier containing κ-alumina, is used to react carbon monoxide, carbon dioxide and hydrogen at temperatures between 225°C and 300°C, the yield of C1-C4 hydrocarbons is 65% or more, and the calorific value of C1-C4 hydrocarbons is 44 MJ / Nm 3 It becomes possible to synthesize the following gases.

[0096] When the catalyst of Comparative Example 1, in which cobalt and rhenium were supported on activated alumina but no iron was supported, was used, the C1-C4 hydrocarbon yield was 83.3% at 225°C, but reached 86.7% at 250°C, 88.4% at 275°C, and 89.7% at 300°C. The C1-C4 hydrocarbon calorific value was 40.5 MJ / Nm at a catalyst bed temperature of 225°C. 3 , 40.1MJ / Nm at 250℃ 3 , 40.0 MJ / Nm at 275°C 3 , 39.9MJ / Nm at 300℃ 3 From the above, in the test at 225°C to 300°C, although a high hydrocarbon yield was obtained, most of the product was methane, and the C1-C4 hydrocarbon calorific value was significantly lower than the result of Example 1.

[0097] Furthermore, when the catalyst of Comparative Example 2, in which cobalt and rhenium were supported on an activated alumina support containing κ-type alumina obtained by calcining commercially available 2-4 mm spherical activated alumina in an electric furnace with air circulation for 6 hours, was used, a high hydrocarbon yield was obtained, but it was not possible to obtain a high yield of high calorific value components. Similarly, when the catalyst of Comparative Example 3, in which cobalt, rhenium, and nickel were supported on a calcined activated alumina support, was used as the catalyst, a high hydrocarbon yield was obtained, but it was not possible to obtain a high yield of high calorific value components. From these results, it is difficult to obtain a high yield of high calorific value components using a catalyst that does not contain iron, and iron must be included in a catalyst for producing high calorific value components. Next, when Comparative Examples 4 and 5, which used zirconia as a support and supported cobalt, rhenium, nickel, and iron, were used as catalysts, high hydrocarbon yields were obtained in tests at 225°C to 300°C. In Comparative Example 4, even though the supported amounts of cobalt, rhenium, nickel, and iron were the same as in Example 4, the calorific value of C1-C4 hydrocarbons was significantly reduced, suggesting that γ-type or κ-type activated alumina is desirable as a support for the catalyst for producing high calorific value components according to the embodiment of the present invention. [Industrial Applicability]

[0098] The present invention can be used in a process for producing a high-heat-generating fuel gas, which has a higher heat value per unit volume than methane and can be used as a source of city gas, from a mixed gas containing hydrogen and at least one of carbon monoxide or carbon dioxide.

[0099] From the above results, it is clear that by using the catalyst for producing a high calorific value fuel gas of the present invention, a high calorific value fuel gas composed of C1-C4 hydrocarbons and having a high calorific value can be obtained in high yield from a mixed gas containing at least one of carbon monoxide or carbon dioxide and hydrogen.

[0100] The configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, as long as no contradiction arises. Furthermore, the embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited to these, and can be modified as appropriate within the scope that does not deviate from the purpose of the present invention.

Claims

1. A catalyst for producing a high calorific value fuel gas, comprising iron, cobalt, and rhenium supported on a carrier primarily composed of activated alumina, wherein the amount of cobalt supported is 5.0 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the carrier, the amount of iron supported is 0.10 parts by mass or more and 5.0 parts by mass or less per 100 parts by mass of the carrier, and the amount of rhenium supported is 1.0 parts by mass or more and 3.0 parts by mass or less per 100 parts by mass of the carrier.

2. The catalyst for producing a high calorific value fuel gas according to claim 1 , wherein the support comprises κ-type alumina.

3. 2. The catalyst for producing a high calorific value fuel gas according to claim 1, wherein the catalyst comprises 1.0 to 5.0 parts by mass of nickel per 100 parts by mass of the carrier.

4. 3. The catalyst for producing a high calorific value fuel gas according to claim 2, wherein the catalyst comprises 1.0 to 5.0 parts by mass of nickel per 100 parts by mass of the carrier.

5. 5. The catalyst for producing a high calorific value fuel gas according to claim 1, wherein the support is a molded body having a particle size of 1.0 mm or more and 20 mm or less.

6. A method for producing a catalyst for producing a high calorific value fuel gas, which contains cobalt, iron, and rhenium supported on a carrier mainly composed of activated alumina, the method comprising the steps of: an impregnation step of impregnating the carrier with an aqueous solution containing water-soluble compounds of cobalt, iron, and rhenium to obtain an impregnated body; a drying step of drying the impregnated body to obtain a dried body; and a calcination step of calcining the dried body in air at a temperature of 350°C to 500°C.

7. The method for producing a catalyst for producing a high calorific value fuel gas according to claim 6, wherein the support comprises κ-type alumina.

8. The method for producing a catalyst for producing a high calorific value fuel gas according to claim 6, wherein the catalyst contains nickel.

9. The method for producing a catalyst for producing a high calorific value fuel gas according to claim 7 , wherein the catalyst contains nickel.

10. 10. The method for producing a catalyst for producing a high calorific value fuel gas according to claim 6, wherein the support is a molded body having a particle size of 1.0 mm or more and 20 mm or less.

11. A method for producing a high calorific value fuel gas, comprising contacting a mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen with a catalyst comprising activated alumina supporting cobalt, rhenium, and iron at a temperature of 225°C to 325°C, to obtain a gas containing methane as the main component and also containing ethane, propane, and butane.

12. A method for producing a high calorific value fuel gas, comprising contacting a mixed gas containing at least one of carbon monoxide and carbon dioxide and hydrogen with a catalyst comprising activated alumina supporting cobalt, rhenium, nickel, and iron at a temperature of 225°C to 325°C, to obtain a gas containing methane as the main component and also containing ethane, propane, and butane.

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