Method for producing hydrocarbons and slurry bed reactor

Abstract

This invention provides a technology to improve reaction efficiency in the production of hydrocarbons using the FT method. [Solution] A method for producing hydrocarbons by the Fischer-Tropsch process, comprising contacting a slurry containing a catalyst and an organic solvent with the raw material gas supplied from the bottom of the reactor body in a slurry bed reactor comprising a reactor body and a filter for passing and dispersing raw material gas within the reactor body, wherein the catalyst comprises a catalytic metal and a carrier supporting the catalytic metal, the particle size of the carrier supporting the catalyst is 1 μm or more and 1000 μm or less, and when the minimum particle size of the carrier is φc and the pore size of the filter is φf, the method satisfies the following formula (1). 0.1 ≤ (φf / φc) < 10.0 (1).

Description

Technical Field

[0001] The present invention relates to a method for producing hydrocarbons and a slurry bed reactor.

Background Art

[0002] Hydrocarbons can be produced, for example, by the Fischer-Tropsch method (hereinafter also referred to as the "FT method"). The FT method is a technique for synthesizing hydrocarbons from carbon monoxide (CO) and hydrogen (H2) using a catalytic reaction. In the FT method, hydrocarbons are synthesized by a gas-solid phase catalytic reaction in which a raw material gas is brought into contact with a solid catalyst in a reactor. Hereinafter, the hydrocarbon synthesis reaction by the FT method is also referred to as the "FT reaction". Examples of the reactor used in the FT method include various types of reactors such as a fixed bed, a slurry bed, and a fluidized bed.

[0003] Patent Document 1 describes a reactor for FT synthesis reaction provided with a sparger portion disposed at the lower part inside the reactor body and communicating with a gas supply pipe for ejecting synthesis gas.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the production of hydrocarbons by the FT method, assuming the use of a slurry bed reactor, there is room for further improving the reaction efficiency in the prior art. In view of the above, the present invention provides a technique for improving the reaction efficiency in the production of hydrocarbons by the FT method.

Means for Solving the Problems

[0006] That is, the present invention includes the following aspects. [1] A method for producing hydrocarbons by the Fischer-Tropsch process, The slurry bed reactor comprises a reactor body and a filter (also called a sparger) for passing and dispersing the raw material gas within the reactor body, and includes contacting a slurry containing a catalyst and an organic solvent with the raw material gas supplied from the bottom of the reactor body. The catalyst comprises a catalytic metal and a carrier supporting the catalytic metal. The particle size of the support on which the catalyst is supported is 1 μm or more and 1000 μm or less. When the minimum particle size of the carrier is φc and the pore size of the filter is φf, a method that satisfies the following equation (1) 0.1 ≤ (φf / φc) < 10.0 (1). [2] When the minimum particle size of the carrier is φc and the pore size of the filter is φf, the method according to [1] above satisfies the following formula (2). 0.5 ≤ (φf / φc) ≤ 5.0 (2). [3] The method according to [1] or [2] above, wherein the pore size φf of the filter is 25 μm or more and 150 μm or less. [4] The method according to any one of the above [1] to [3], wherein the catalyst comprises at least one catalyst metal selected from the group consisting of cobalt, nickel, ruthenium, and iron. [5] The method according to any one of the above [1] to [4], wherein the amount of catalyst metal supported on the carrier is 5% or more and 30% or less as a mass ratio of the catalyst metal to the catalyst. [6] The method according to any one of the above [1] to [5], wherein the carrier contains silica. [7] The method according to any one of the above [1] to [6], wherein the particle size of the carrier is 10 μm or more and 300 μm or less. [8] The method according to any one of the above [1] to [7], wherein the minimum particle size φc of the carrier is 5 μm or more and 100 μm or less. [9] The method according to any one of the above [1] to [8], wherein the concentration of the catalyst in the slurry is 2.5% or more and 40% or less as the ratio of the mass of the catalyst to the volume of the slurry.

[10] The method according to any one of the above [1] to [9], wherein the flow rate of the raw material gas supplied from the bottom of the reactor body is 1 L / min or more and 20 L / min or less.

[11] The method according to any one of the above [1] to

[10] , wherein the temperature inside the reactor body is 100°C or more and 300°C or less.

[12] The method according to any one of the above [1] to

[11] , wherein the pressure inside the reactor body is 0.1 MPa or more and less than 2.0 MPa.

[13] A slurry bed reactor for producing hydrocarbons by the Fischer-Tropsch process, The reactor body and A gas supply unit is configured to bring a slurry containing a catalyst and an organic solvent into contact with the raw material gas by supplying the raw material gas from the lower part of the reactor body. The reactor body is provided with a filter located at the bottom of the reactor body for passing and dispersing the raw material gas within the reactor body, When the minimum particle size of the catalyst support is φc and the pore size of the filter is φf, a slurry bed reactor satisfies the following equation (1). 0.1 ≤ (φf / φc) < 10.0 (1). [Effects of the Invention]

[0007] According to the present invention, a technique for improving reaction efficiency in the production of hydrocarbons by the FT method can be provided. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram illustrating an example of the configuration of a slurry bed reactor. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments for implementing the present invention (hereinafter also referred to as "the present embodiments") will be described in detail while appropriately referring to the drawings. The following present embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be appropriately modified and implemented within the scope of its gist. In addition, although there may be cases where explanations are made with reference to the drawings, the same or corresponding elements in each drawing are denoted by the same reference numerals, and redundant explanations are omitted. The positional relationships such as up, down, left, and right in the drawings are based on the positional relationships shown in the drawings unless otherwise specified. Further, the dimensional ratios of each configuration described by the drawings are not limited to the ratios shown in the drawings.

[0010] <Slurry bed reactor> The slurry bed reactor of the present embodiment is a slurry bed reactor for producing hydrocarbons by the Fischer-Tropsch method, and includes a reactor main body, and a gas supply unit configured to bring a slurry containing a catalyst and an organic solvent into contact with the raw material gas by supplying the raw material gas from the lower part of the reactor main body, and a filter disposed at the lower part of the reactor main body for passing and dispersing the raw material gas in the reactor. When the minimum particle diameter of the carrier of the catalyst is φc and the filtration pore diameter of the filter is φf, the following formula (1) is satisfied. 0.1≦(φf / φc)<10.0 (1) Since the slurry bed reactor of the present embodiment is configured as described above, the reaction efficiency can be improved in the production of hydrocarbons by the FT method. In the present embodiment, the improvement (enhancement) of the reaction efficiency means that one or both of the conversion rate of carbon monoxide and the chain growth rate are improved (enhanced).

[0011] FIG. 1 is a schematic diagram for explaining a configuration example of a slurry bed reactor. In the example of FIG. 1, the slurry bed reactor 100 includes a reactor main body 10 and a filter 20. Although not shown in FIG. 1, the slurry bed reactor 100 includes a gas supply unit for supplying a raw material gas from the lower part of the reactor main body. Hereinafter, each of these configuration examples will be described.

[0012] (Reactor body) The reactor body 10 can be appropriately designed to serve as the reaction field for the FT reaction. For example, the reactor body 10 can be a heat-resistant and pressure-resistant container configured to withstand the reaction conditions of the FT reaction. The capacity of the reactor body 10 is not particularly limited, but may be, for example, 1000 L or less.

[0013] The FT reaction that can proceed within the reactor body 10 is a gas-liquid catalytic reaction. In this embodiment, the raw material gas SG usually has a lower specific gravity than the slurry SL, and when blown into the slurry SL, it moves upward within the slurry SL. In this way, as the raw material gas SG passes through the slurry SL in the reactor body 10, the raw material gas SG comes into contact with the catalyst CT in the slurry SL, and the FT reaction proceeds. The reaction raw materials and reaction products used in such an FT reaction may include liquids and gases. Therefore, the reactor body 10 can be configured to allow liquids and gases to be introduced from the outside into the inside and to be discharged from the inside into the outside. The gas-liquid catalytic reaction described above is also called a slurry bed reaction. Slurry bed FT reactions tend to have superior temperature controllability compared to fixed bed FT reactions, etc.

[0014] Figure 1 shows an example in which slurry SL is introduced into the reactor body 10 up to the slurry liquid level height LH. In this embodiment, "slurry liquid level height LH" corresponds to a value that serves as a guideline for the liquid level height of slurry SL during the operation of the slurry bed reactor 100 (during the FT reaction). In particular, during the operation of the slurry bed reactor 100, the liquid level height of slurry SL may fluctuate over time. Therefore, the actual liquid level height of slurry SL does not necessarily coincide with the slurry liquid level height LH, and may be higher or lower than the slurry liquid level height LH. The slurry liquid level height LH may be input to a control unit that controls the entire slurry bed reactor and managed as a reference value for the liquid level height of slurry SL during the operation of the slurry bed reactor 100 (during the FT reaction).

[0015] The reactor body 10 may be configured to allow slurry SL to be introduced into it from the outside. The reactor body 10 may also be configured to allow slurry SL inside to be discharged to the outside. The introduction of slurry SL into the reactor body 10 and the discharge of slurry SL from the reactor body 10 may be carried out via piping (not shown). The piping for introducing slurry SL into the reactor body 10 may be formed, for example, in the top, side, or bottom of the reactor body 10. The slurry supply pipe may be connected to a slurry supply source. The slurry supply pipe may also be connected to a catalyst source and an organic solvent source, so that the catalyst CT and the organic solvent SV are mixed inside the reactor body 10 to prepare slurry SL.

[0016] In the slurry SL, a product liquid may be generated over time as the FT reaction progresses. The product liquid may be discharged to the outside of the reactor body 10 through a product liquid discharge tube (not shown). The product liquid discharged to the outside of the reactor body may be purified by a purification method (not shown). The product liquid discharge tube may be formed on the side of the reactor body 10, and its height may be determined based on the slurry liquid level LH. For example, the product liquid discharge tube may be formed on the side of the reactor body 10 at a position between "slurry liquid level LH ​​× 1 / 2" and "slurry liquid level LH". The slurry SL near the product liquid discharge tube may be discharged to the outside of the reactor body 10 together with the product liquid via the product liquid discharge tube. The slurry SL discharged to the outside of the reactor body 10 can be separated from the product liquid by a purification method or the like and reused in the FT reaction as appropriate.

[0017] In the FT reaction, in addition to the product liquid, a product gas may also be produced. The product gas may be discharged to the outside of the reactor body 10 through a product gas outlet pipe (not shown) formed at the top of the reactor body 10. The product gas discharged to the outside of the reactor body 10 may be purified by a purification means (not shown). The raw material gas SG supplied from the side or bottom of the reactor body 10 may, for example, rise through the slurry SL inside the reactor body 10 and move to the gas phase portion inside the reactor body 10. The raw material gas SG that has moved to the gas phase portion may be discharged to the outside of the reactor body 10 together with the product gas via the product gas outlet pipe. The raw material gas SG discharged to the outside of the reactor body 10 may be separated from the product gas by the purification means described above and reused in the FT reaction as appropriate.

[0018] In the FT reaction, the raw material gas SG, which is the raw material for synthesis, is supplied from the bottom of the reactor body 10 from the gas supply unit described later. Here, "bottom" includes the bottom and a part of the side of the reactor body 10. In this embodiment, the raw material gas SG used usually moves upward in the slurry SL due to the difference in specific gravity with the slurry SL. Therefore, when the raw material gas SG is supplied from the bottom of the reactor body 10, it tends to be possible to ensure a sufficient distance for the raw material gas SG to move within the slurry SL. As a result, the catalyst CT and the raw material gas SG tend to come into contact efficiently. However, when the raw material gas SG is supplied from the side of the reactor body 10, due to the difference in specific gravity between the raw material gas SG and the slurry SL, a dead space tends to be created near the inner wall of the reactor on the opposite side from the side, where the raw material gas SG is difficult to reach. Considering this dead space, and from the viewpoint of further increasing the distance for the raw material gas SG to move within the slurry SL, it is preferable that the reactor body 10 is configured so that the raw material gas SG is supplied from the bottom of the reactor body 10. As an example, as shown in Figure 1, it is preferable that the raw material gas supply pipe 10c is formed at the bottom of the reactor body 10.

[0019] When the raw material gas SG is supplied from the side of the reactor body 10, the raw material gas supply pipe 10c may be formed on the side of the reactor body 10, and its height may be determined based on the slurry liquid level height LH. For example, the raw material gas supply pipe 10c may be formed on the side of the reactor body 10 at a position between "the bottom of the reactor" and "1 / 3 of the slurry liquid level height LH".

[0020] (Gas Supply Department) The gas supply unit (not shown) supplies the raw material gas SG to the reactor body 10. The gas supply unit may be configured to store the raw material gas SG when the FT reaction is not being performed and to supply the raw material gas SG to the reactor body 10 when the FT reaction is being performed. The gas supply unit may be connected to the reactor body 10 via the raw material gas supply pipe 10c. The gas supply unit may be equipped with flow control means such as a flow meter to monitor the flow rate of the raw material gas SG and a valve to control the flow rate.

[0021] (filter) The slurry bed reactor 100 of this embodiment is equipped with a filter (also called a "sparger") as a means of gas dispersion. The raw material gas SG that passes through the filter becomes tiny bubbles in the slurry SL and is dispersed more uniformly within the reactor body 10. The more uniformly the raw material gas SG is dispersed within the reactor body 10, the more opportunities there are for contact between the raw material gas SG and the catalyst CT, thus improving the reaction efficiency.

[0022] In the slurry bed reactor of this embodiment, the pore size of the filter is adjusted to a specific range relative to the minimum particle size of the catalyst support. Specifically, when the minimum particle size of the catalyst support is φc and the pore size of the filter is φf, the following equation (1) is satisfied. 0.1 ≤ (φf / φc) < 10.0 (1) By adjusting the filter pore size φf relative to the minimum particle size φc of the catalyst support to the above-mentioned specific range, it is possible to suppress the outflow of the catalyst CT from the reactor body 10 through the filter while generating fine bubbles of the raw material gas. This increases the contact area between the raw material gas and the catalyst, thereby improving the reaction efficiency.

[0023] The material of the filter is not particularly limited and can be, for example, ceramic, glass, aluminum, Monel, nickel, SUS316, SUS304, or other types of stainless steel. Among these, stainless steel is preferred from the viewpoint of heat resistance and corrosion resistance.

[0024] (Other configurations) The slurry bed reactor 100 may include stirring means configured to agitate the slurry SL and raw material gas SG supplied into the reactor body 10. When the slurry SL and raw material gas SG supplied into the reactor body 10 are agitated by the stirring means, the opportunity for contact between the slurry SL and the raw material gas SG increases, which can improve the reaction efficiency.

[0025] The slurry bed reactor 100 may be equipped with heat exchange means for maintaining the temperature inside the reactor body 10 within a predetermined range. Since the FT reaction is an exothermic reaction, the heat exchange means may be configured to suppress an excessive temperature rise inside the reactor body 10. For example, the heat exchange means may include a cooling medium introduction pipe for introducing a cooling medium into the heat exchange means and a heated steam outlet pipe for discharging heated steam from the heat exchange means.

[0026] <Method for producing hydrocarbons> The hydrocarbon production method of this embodiment (hereinafter also referred to as "the method of this embodiment") is a method for producing hydrocarbons by the Fischer-Tropsch process, comprising contacting a slurry containing a catalyst and an organic solvent with the raw material gas supplied from the bottom of the reactor body in a slurry bed reactor comprising a reactor body and a filter for passing and dispersing raw material gas within the reactor body, wherein the catalyst comprises a catalytic metal and a carrier supporting the catalytic metal, the particle size of the carrier supporting the catalyst is 1 μm or more and 1000 μm or less, and when the minimum particle size of the carrier is φc and the pore size of the filter is φf, the following formula (1) is satisfied. 0.1 ≤ (φf / φc) < 10.0 (1) In this embodiment, the method is achieved by adjusting the pore size φf of the filter to the minimum particle size φc of the catalyst support within the specified range. This suppresses the outflow of the catalyst CT from the reactor body 10 through the filter while generating fine bubbles of the raw material gas. As a result, the contact area between the raw material gas and the catalyst increases, improving the reaction efficiency. The numerical range of (φf / φc) is preferably 0.2 to 5.0, more preferably 0.5 to 3.0, and even more preferably 0.7 to 2.0.

[0027] In the method of this embodiment, the pore size φf of the filter used as a gas dispersion means is preferably 25 μm or more and 150 μm or less, more preferably 40 μm or more and 120 μm or less, and even more preferably 50 μm or more and 100 μm or less. When the pore size φf of the filter is 25 μm or more, the pressure loss tends to decrease, and when it is 150 μm or less, the reaction efficiency tends to improve. The pore size of the filter can be measured directly with a microscope or the like, or it can be measured indirectly using the mercury intrusion method or the gas adsorption method. In the case of a pore size on the order of tens of μm as in this embodiment, it refers to a value calculated as the average value of 10 arbitrary pores selected using an electron microscope or optical microscope.

[0028] The method of this embodiment may be carried out using the slurry bed reactor 100 illustrated in Figure 1, or it may be carried out using other equipment. In the following description, the case in which the method of this embodiment is carried out using the slurry bed reactor 100 will be explained as an example. Hereinafter, the step of supplying slurry to the reactor will be referred to as "step S1", and the step of supplying raw material gas to the reactor will be referred to as "step S2".

[0029] (Process S1) In step S1, slurry SL is supplied to the slurry bed reactor 100. In this embodiment, slurry SL can be supplied into the reactor body 10 from a slurry supply pipe (not shown). As shown in Figure 1, slurry SL contains an organic solvent SV and a catalyst CT.

[0030] The organic solvent SV serves as a medium for suspending the catalyst CT and introducing it into the reactor body for the gas-liquid catalytic reaction. The organic solvent SV may be, for example, a liquid hydrocarbon. The liquid hydrocarbon may be, for example, a saturated hydrocarbon having 10 to 20 carbon atoms. Among these, liquid hydrocarbons having 15 or more carbon atoms with a volatilization temperature of 200°C or higher are preferred, and pentadecane, hexadecane, heptadecane, and octadecane are even more preferred.

[0031] The catalyst CT comprises a catalyst metal MT and a carrier SP supporting the catalyst metal MT. The catalyst metal MT may contain at least one selected from the group consisting of cobalt, nickel, ruthenium, and iron. From the viewpoint of obtaining middle distillates such as diesel fuel, jet fuel, and kerosene, it is preferable that the catalyst metal MT contains cobalt. The carrier SP may contain at least one selected from the group consisting of silica (SiO2), alumina (Al2O3), and zeolite (aluminosilicate). From the viewpoint of exhibiting performance derived from the catalyst metal MT and contact efficiency with the raw material gas, it is preferable that the carrier SP contains silica. The catalyst CT may further contain at least one rare earth element selected from the group consisting of yttrium, cerium, lanthanum, praseodymium, neodymium, and holmium, at least one alkali metal selected from the group consisting of sodium, potassium, rubidium, and cesium, at least one alkaline earth metal selected from the group consisting of beryllium, magnesium, calcium, strontium, and barium, and copper, etc.

[0032] The amount of material supported in the catalyst CT is expressed as the mass ratio of the catalyst metal to the catalyst and may be adjusted as appropriate. In this embodiment, the amount of material supported may be 5% or more and 30% or less. When the amount of material supported is 5% or more, the carbon monoxide conversion rate tends to improve. When the amount of material supported is 30% or less, the chain growth rate tends to improve. From the above viewpoint, the amount of material supported may be 10% or more and 25% or less.

[0033] The shape of the catalyst CT is not particularly limited and may be, for example, in powder form. The size of the catalyst CT is also not particularly limited and may be, for example, 0.07 mm or more and 0.2 mm or less as measured by laser diffraction.

[0034] The particle size of the support material SP carrying the catalyst metal MT is 1 μm or more and 1000 μm or less, preferably 10 μm or more and 300 μm or less. When the particle size of the support material SP is 1 μm or more, the outflow of the catalyst from the reactor body 10 through the filter tends to be suppressed, and when it is 1000 μm or less, the specific surface area of ​​the catalyst increases, which tends to improve the reaction efficiency.

[0035] The minimum particle size φc of the support SP carrying the catalyst metal MT is adjusted in relation to the pore size φf of the filter described above, but is preferably 5 μm to 100 μm, more preferably 20 μm to 90 μm, and even more preferably 40 μm to 80 μm. When the minimum particle size φc of the support SP is 5 μm or more, the outflow of the catalyst from the reactor body 10 through the filter tends to be suppressed, and when it is 100 μm or less, the specific surface area of ​​the catalyst increases, which tends to improve the reaction efficiency.

[0036] The particle size of the catalyst support is defined as the value measured by laser diffraction scattering, in accordance with the description in WO2024 / 111649. The minimum particle size of the support is defined as the minimum value that shows Dn10 in the cumulative distribution function of the particle size distribution. This can be rephrased as the smallest particle size possessed by 10% of the total particles, based on number.

[0037] The concentration of catalyst CT in slurry SL is expressed as the ratio of the mass of the catalyst to the volume of the slurry and may be adjusted as appropriate. In this embodiment, the above ratio may be 2.5% or more and 40% or less. When the above ratio is 2.5% or more, the carbon monoxide conversion rate and chain growth rate tend to improve. When the above ratio is 40% or less, it tends to prevent excessive precipitation of catalyst CT in slurry SL.

[0038] (Process S2) In step S2, the raw material gas SG is supplied to the slurry bed reactor 100. In this embodiment, the raw material gas SG can be supplied from the gas supply unit to the reactor body 10 through the filter 20. When the raw material gas SG is supplied to the reactor body 10, the catalyst CT contained in the slurry SL inside the reactor body 10 comes into contact with the raw material gas SG, and the FT reaction proceeds.

[0039] The raw material gas SG may be a mixed gas of hydrogen (H2) and carbon monoxide (CO). The raw material gas SG in this embodiment may further contain carbon dioxide (CO2). From the viewpoint that the rate of the FT reaction depends on the partial pressure of hydrogen, the partial pressure ratio (molar ratio) of hydrogen to the total amount of carbon monoxide and carbon dioxide in the raw material gas SG may be 0.6 to 2.7, 0.8 to 2.5, or 1 to 2.3. The ratio of carbon monoxide to carbon dioxide in the raw material gas SG may also be adjusted as appropriate. For example, from the viewpoint of carbon recycling, it is preferable to increase the ratio of carbon dioxide, and from the viewpoint of increasing the conversion rate to hydrocarbons, it is preferable to increase the ratio of carbon monoxide. In this embodiment, the ratio of carbon dioxide to carbon monoxide, as the ratio of carbon dioxide to the total amount of carbon monoxide and carbon dioxide, may be 1 volume% or more, 10 volume% or more, 30 volume% or more, or 40 volume% or more. Other components in the raw material gas SG may include, for example, sulfur, organic nitrogen, phosphorus, etc. The content of the above-mentioned other components may be 20% by volume or less relative to 100% by volume of the raw material gas SG.

[0040] The flow rate of the raw material gas SG supplied to the slurry bed reactor 100 is preferably 1 L / min or more and 20 L / min or less, more preferably 3 L / min or more and 15 L / min or less, and even more preferably 5 L / min or more and 12 L / min or less. When the flow rate of the raw material gas SG is 1 L / min or more, the amount of catalyst supplied to the reactor body tends to be sufficient, and when it is 20 L / min or less, the pressure loss tends to be reduced.

[0041] When the raw material gas SG comes into contact with the catalyst CT in the slurry SL, the FT reaction proceeds, and a liquid product may be generated. The liquid product is a hydrocarbon with a relatively high boiling point and a high number of carbon atoms among the hydrocarbons produced by the FT reaction, and may be, for example, a heavy naphtha fraction (crude gasoline), kerosene, diesel fuel, or other intermediate distillates.

[0042] When the raw material gas SG comes into contact with the catalyst CT in the slurry SL, the FT reaction proceeds and a product gas may be generated. The product gas is a hydrocarbon with a relatively low boiling point and a low number of carbon atoms among the hydrocarbons produced by the FT reaction, and may be, for example, a hydrocarbon with 1 to 4 carbon atoms. Specific examples of such hydrocarbons include methane, ethane, ethylene, propane, propylene, butane, and butene.

[0043] (Other conditions) At least one of steps S1 and S2 may include controlling the ratio of the slurry liquid level height LH to the inner diameter Dc of the slurry bed reactor, expressed as LH / Dc, to 1.5 to 300.

[0044] In at least one of steps S1 and S2, the temperature inside the reactor body 10 is 100°C or higher and 300°C or lower. Also, in at least one of steps S1 and S2, the pressure inside the reactor body 10 is greater than 0 MPa and less than 2.0 MPa, preferably 0.1 MPa or higher and less than 2.0 MPa. When the above pressure is controlled to less than 2.0 MPa, the effects of pressure fluctuations are suppressed, and a high reaction efficiency tends to be maintained over a long period of time. From the above viewpoint, the above pressure may be greater than 0 MPa and less than 1.5 MPa. When the above pressure is controlled to less than 1.5 MPa, the effects of pressure fluctuations are suppressed even further, and a high reaction efficiency tends to be maintained over an even longer period of time. Also, the above pressure may be greater than 0 MPa and less than 1.0 MPa. When the above pressure is controlled to less than 1.5 MPa, the effects of pressure fluctuations are suppressed even further, and a high reaction efficiency tends to be maintained over an even longer period of time. [Examples]

[0045] The embodiments will be described in more detail below based on examples. These embodiments are not limited to these examples.

[0046] (Carrier particle size and carrier minimum particle size) The particle size of the catalyst carrier was measured by laser diffraction scattering in accordance with the description in WO2024 / 111649. Furthermore, the minimum value showing Dn10 in the cumulative distribution function of the particle size distribution was defined as the minimum particle size of the carrier.

[0047] (Sparger pore size) The pore size of the sparger was determined by selecting 10 arbitrary pores using an optical microscope and calculating the average value of these values.

[0048] [Example 1] (reactor) Using a reactor with a configuration similar to the slurry bed reactor 100 shown in Figure 1, hydrocarbons were produced by the FT method as follows. The inner diameter of the reactor body 10 was 10 cm, and the pore size of the filter 20 (sparger) located at the bottom of the reactor 100 was 10 μm.

[0049] (Slurry preparation) Silica gel (Merck: Silica gel 60,70-230 mesh) was placed in a porcelain dish and heated in a muffle furnace at 120°C for 30 minutes to dehydrate it. After dehydration, it was calcined at 500°C for 3 hours to obtain a silica support precursor. Next, cobalt nitrate hexahydrate was transferred to a beaker and dissolved in pure water to obtain an activated metal impregnation solution. After calcination, the silica gel, which had been brought to room temperature, was transferred to a round-bottom flask, and the activated metal impregnation solution was added to obtain a catalyst slurry. Using a rotary vaporizer, the water was removed over 1 hour at 50°C while maintaining a pressure of 30 mmHg (4 kPa) to obtain a pale pink powder. This was transferred to a quartz furnace tube and heated at 270°C for 10 minutes while passing air through at 100-200 mL / min (stp), then the temperature was raised to 500°C and calcined for 3 hours. The obtained catalyst precursor (Co3O4 / SiO2) was transferred to a sample bottle and stored at room temperature under air. Next, the catalyst precursor (Co3O4 / SiO2) was packed into the slurry bed reaction vessel 100, and the temperature was raised to 150°C while aeration with Ar at a set flow rate of 40 mL / min. Then, the aeration gas was switched to hydrogen and aeration was carried out at a set flow rate of 50 mL / min, and the temperature was raised to 450°C for 1 hour of reduction. As described above, a catalyst was prepared by supporting cobalt on a silica support. In this catalyst, the particle size of the silica support ranged from 63 to 200 μm, with a minimum particle size of 63 μm. The mass ratio of the silica support (specific gravity 1.8) to the cobalt (specific gravity 8.9) was 4:1, and the amount of catalyst supported was 20% by mass. The specific gravity of the catalyst was 3.3. SEM-EDS was used to measure the amount of catalyst metal supported. Hexadecane (specific gravity 0.77) was used as the organic solvent, and the catalyst was mixed with it to prepare a slurry so that the catalyst concentration was 10% (catalyst mass / slurry volume).

[0050] (Synthesis reaction) First, the slurry described above was supplied into the reactor body (inner diameter Dc = 10 cm). The supply rate was adjusted so that the slurry level LH ​​in the reactor body was 30 cm. Next, the supply of raw material gas was started, thereby initiating the hydrocarbon synthesis reaction. The raw material gas was a mixed gas containing hydrogen gas and carbon monoxide gas in a molar ratio of 2:1, supplied from the bottom of the reactor body 10 through the filter 20. The gas flow rate at this time was 10 L / min. The reaction temperature was set to 230°C and the pressure to 0.9 MPa. The reaction time was set to 10 hours, which is the time from reaching the reaction temperature until the temperature was reduced. During this time, the product liquid was withdrawn from the product liquid outlet pipe, and the product gas was withdrawn from the product gas outlet pipe.

[0051] (Reaction performance) After the reaction was complete, the reaction results were evaluated as follows. For the analysis of H2, CO, CH4, and CO2, a gas chromatograph TCD-GC (GC323, GL Sciences) with a thermal conductivity detector was used. For the analysis of hydrocarbons with 1 to 6 carbon atoms, a gas chromatograph with a flame ionization detector was used. Argon was used as the carrier gas. For hydrocarbons with 6 or more carbon atoms, the supernatant of the standing slurry was collected for analysis. A separation column was attached to measure the distribution of the generated oil. From the above analysis results, the CO conversion rate was calculated using the following formula.

[0052]

number

[0053] Specifically, the carbon monoxide conversion rate (CO conversion rate) and the chain growth rate α (chain growth probability α) were calculated based on the flow rate of the raw material gas, the flow rates of the generated gas and liquid, and the results of analysis by gas chromatography. The chain growth rate α was calculated using the formula α = Kp / (Kp + Kd). Here, Kp and Kd were the rate constants for the chain termination reaction and the chain growth reaction, respectively. The above calculations can be performed by referring to "Organic Synthesis Chemistry," Vol. 41, No. 6 (1983), pp. 532-566, edited by the Society of Synthetic Organic Chemistry, Japan. The CO conversion rate and chain growth rate in Example 1 were 50% and 0.5, respectively.

[0054] [Examples 2-7] As shown in Table 1 below, the synthesis reaction was carried out in the same manner as in Example 1, except that the sparger pore size was changed, and the reaction performance was evaluated. The results are also shown in Table 1.

[0055] [Table 1]

[0056] [Comparative Examples 1-3] As shown in Table 2 below, the synthesis reaction was carried out in the same manner as in Example 1, except that the sparger pore size was changed, and the reaction performance was evaluated. The results are also shown in Table 2.

[0057] [Table 2]

[0058] As shown in Table 1, in Examples 1 to 7, the φf / φc value was adjusted to a range that allowed for the generation of fine bubbles in the raw material gas while suppressing the outflow of the catalyst through the filter from the reactor body. As a result, the contact area between the raw material gas and the catalyst was increased, making it possible to achieve a high CO conversion rate and chain growth rate. On the other hand, as shown in Table 2, in Comparative Examples 1 and 2, the φf / φc values ​​were low, and pressure loss occurred, resulting in a decrease in CO conversion rate and chain growth rate. In Comparative Example 3, the φf / φc value was high, and the catalyst fell (flowed out) from the reactor body through the filter, making it impossible to carry out the synthesis reaction. [Explanation of Symbols]

[0059] 100...Slurry bed reactor, 10...Reactor body, 10c...Raw material gas supply pipe, LH...Slurry liquid level height, Dc...Inner diameter, SG...Raw material gas, SL...Slurry, SV...Organic solvent, CT...Catalyst, MT...Catalyst metal, SP...Carrier, 20...Filter

Claims

1. A method for producing hydrocarbons by the Fischer-Tropsch process, The slurry bed reactor comprises a reactor body and a filter for passing and dispersing the raw material gas within the reactor body, and includes contacting a slurry containing a catalyst and an organic solvent with the raw material gas supplied from the bottom of the reactor body. The catalyst comprises a catalytic metal and a carrier supporting the catalytic metal. The particle size of the support on which the catalyst is supported is 1 μm or more and 1000 μm or less. When the minimum particle size of the carrier is φc and the pore size of the filter is φf, a method that satisfies the following formula (1) 0.1≦(φf / φc)<10.0 (1).

2. The method according to claim 1, wherein the minimum particle size of the carrier is φc and the pore size of the filter is φf, satisfying the following formula (2). 0.5≦(φf / φc)≦5.0 (2).

3. The method according to claim 1 or 2, wherein the pore size φf of the filter is 25 μm or more and 150 μm or less.

4. The method according to claim 1 or 2, wherein the catalyst comprises at least one catalyst metal selected from the group consisting of cobalt, nickel, ruthenium, and iron.

5. The method according to claim 1 or 2, wherein the amount of catalyst metal supported on the carrier is 5% or more and 30% or less as a mass ratio of the catalyst metal to the catalyst.

6. The method according to claim 1 or 2, wherein the carrier contains silica.

7. The method according to claim 1 or 2, wherein the particle size of the carrier is 10 μm or more and 300 μm or less.

8. The method according to claim 1 or 2, wherein the minimum particle size φc of the carrier is 5 μm or more and 100 μm or less.

9. The method according to claim 1 or 2, wherein the concentration of the catalyst in the slurry is 2.5% or more and 40% or less as the ratio of the mass of the catalyst to the volume of the slurry.

10. The method according to claim 1 or 2, wherein the flow rate of the raw material gas supplied from the lower part of the reactor body is 1 L / min or more and 20 L / min or less.

11. The method according to claim 1 or 2, wherein the temperature inside the reactor body is 100°C or more and 300°C or less.

12. The method according to claim 1 or 2, wherein the pressure inside the reactor body is 0.1 MPa or more and less than 2.0 MPa.

13. A slurry bed reactor for producing hydrocarbons by the Fischer-Tropsch process, The reactor body and A gas supply unit is configured to bring a slurry containing a catalyst and an organic solvent into contact with the raw material gas by supplying the raw material gas from the lower part of the reactor body. The reactor body is provided with a filter located at the bottom of the reactor body for passing and dispersing the raw material gas within the reactor body, When the minimum particle size of the catalyst support is φc and the pore size of the filter is φf, a slurry bed reactor satisfies the following equation (1). 0.1≦(φf / φc)<10.0 (1).

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