Flow synthesis reactor

Abstract

Provided is a flow synthesis reactor capable of inhibiting a fluid containing a reactant from leaking to the outside. A flow synthesis reactor according to one embodiment of the present invention is provided with a ceramic base material and a catalyst. The ceramic base material is provided with a cylindrical outer circumferential part. The internal space of the outer circumferential part includes a flow path to which a fluid containing a reactant is supplied. The catalyst is capable of promoting a chemical reaction of the reactant. The catalyst is disposed so as to come into contact with the fluid supplied to the flow path. The outer circumferential part has a porosity of 0-10%. The outer circumferential part has a thickness of 1-10 mm.

Description

Flow synthesis reactor

[0001] This invention relates to a flow synthesis reactor.

[0002] Conventionally, the flow method (flow reaction method) has attracted attention because it is superior in energy productivity and can reduce waste compared to the batch reaction method. As a reactor applicable to such a flow method, for example, a reactor has been proposed that comprises: a porous body having multiple flow channels separated by porous walls; a reaction catalyst provided on the surface of the porous walls; and a solution supply unit that supplies a solution containing a gas-phase reactant and a liquid-phase reactant to the porous body (see Patent Document 1).

[0003] Japanese Patent Publication No. 2020-040022

[0004] In recent years, flow precision synthesis, which involves combining multiple flow reactions to synthesize structurally complex organic compounds, has been studied. In such flow precision synthesis, each flow reaction is carried out under various reaction conditions (e.g., fluid velocity, temperature, pressure) depending on the target product. However, in the reaction apparatus described in Patent Document 1, depending on the reaction conditions, the fluid containing the reactants may leak out of the porous material. Particularly in the pharmaceutical and fine chemical fields, where explosive and toxic reactants are handled, there is a strong need to minimize the risk of leakage outside the apparatus. The main objective of the present invention is to provide a flow synthesis reaction apparatus that has a simple configuration but can suppress the leakage of the fluid containing the reactants to the outside.

[0005] [1] A flow synthesis reactor according to one embodiment of the present invention comprises a ceramic substrate and a catalyst. The ceramic substrate has a cylindrical outer periphery. The internal space of the outer periphery includes a channel through which a fluid containing reactants is supplied. The catalyst is capable of promoting the chemical reaction of the reactants. The catalyst is positioned to be in contact with the fluid supplied to the channel. The porosity of the outer periphery is 0% or more and 10% or less. The thickness of the outer periphery is 1 mm or more and 10 mm or less. [2] In the flow synthesis reactor described in [1] above, the thermal conductivity of the ceramic substrate may be 30 W / m·K or more. [3] In the flow synthesis reactor described in [1] or [2] above, the ceramic substrate may further comprise a partition wall. The partition wall is provided on the inside of the outer periphery. The partition wall constitutes a plurality of cells. At least a portion of the plurality of cells includes the channel. [4] In the flow synthesis reactor described in any of [1] to [3] above, the ceramic substrate may contain Si and SiC. [5] In the flow synthesis reactor described in any of [1] to [4] above, the catalyst may contain an active component containing a noble metal element and a carrier supporting the active component. [6] In the flow synthesis reactor described in [5] above, the noble metal element may contain palladium.

[0006] According to embodiments of the present invention, it is possible to suppress leakage of the fluid containing the reactants to the outside, even with a simple configuration.

[0007] Figure 1 is a schematic cross-sectional view of a flow synthesis reactor according to one embodiment of the present invention. Figure 2 is a schematic cross-sectional view of a flow synthesis reactor according to another embodiment of the present invention. Figure 3 is a schematic perspective view of the honeycomb substrate provided in the flow synthesis reactor of Figure 1. Figure 4 is a schematic cross-sectional view of a flow synthesis reactor according to another embodiment of the present invention. Figure 5 is a schematic cross-sectional view of a flow synthesis reactor according to yet another embodiment of the present invention.

[0008] Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments. Furthermore, in order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc., of each part compared to the embodiments; however, these are merely examples and do not limit the interpretation of the present invention.

[0009] A. Flow Synthesis Reactor Figure 1 is a schematic cross-sectional view of a flow synthesis reactor according to one embodiment of the present invention. As shown in Figure 1, in one embodiment, the flow synthesis reactor 100 comprises a ceramic substrate 1 and a catalyst 2. The ceramic substrate 1 has a cylindrical outer periphery 13. The internal space of the outer periphery 13 includes a flow channel 14 into which a fluid containing reactants is supplied. The catalyst 2 is capable of promoting the chemical reaction of the reactants. The catalyst 2 is arranged to be in contact with the fluid supplied to the flow channel 14. The porosity of the outer periphery 13 is 0% or more and 10% or less. The thickness of the outer periphery 13 is 1 mm or more and 10 mm or less. When the porosity of the outer periphery 13 exceeds 0%, the pores present in the outer periphery 13 are typically not communicating with each other. The structure of the outer periphery can be confirmed, for example, by cross-sectional observation using an SEM (scanning electron microscope). The pores present in the outer periphery 13 are confirmed not to be communicating with each other, for example, by measuring the gas permeability, where the gas flow rate in the thickness direction is below the measurement limit. With this configuration, since the porosity and thickness of the outer periphery are within the above-mentioned ranges, leakage of the fluid to the outside can be suppressed when a fluid containing reactants is supplied to the flow path. Therefore, the flow synthesis reaction can be carried out without housing the ceramic substrate with the outer periphery in a housing that does not allow fluid to permeate. As a result, the flow synthesis reaction can be carried out efficiently despite the simple configuration. Examples of fluids supplied to the flow synthesis reactor include liquids, gases, mixtures of liquids and gases, mixtures of liquids and solids, and mixtures of liquids, solids and gases, with liquids being preferred.

[0010] A-1. Ceramic Substrate The ceramic substrate 1 has an outer periphery 13 as described above. The outer periphery 13 extends in a predetermined direction. The outer periphery 13 has a first end face E1 (inlet end face) and a second end face E2 (outlet end face) in the axial direction in which the axis extends. The second end face E2 is located away from the first end face E1 in the axial direction of the outer periphery 13. Examples of the shape of the outer periphery 13 include a cylindrical shape and a rectangular tube shape. In one embodiment, the ceramic substrate 1 has an outer periphery 13 having a cylindrical shape. The inner diameter and length of the outer periphery 13 can be appropriately set according to the purpose. The inner diameter of the outer periphery 13 is, for example, 10 mm to 200 mm. The length (dimensional in the axial direction) of the outer periphery 13 is, for example, 50 mm to 300 mm.

[0011] The porosity of the outer periphery 13 is preferably 8.0% or less, more preferably 5.0% or less, and even more preferably 3.5% or less. When the porosity of the outer periphery is below these upper limits, leakage of fluid from the flow synthesis reactor to the outside can be reliably suppressed. When the porosity of the outer periphery 13 exceeds 0%, the average pore diameter in the outer periphery 13 is, for example, 0.5 μm or less, and preferably 0.3 μm or less. On the other hand, the average pore diameter in the outer periphery 13 is, for example, 0.05 μm or more. The porosity and average pore diameter of the ceramic substrate are measured, for example, in accordance with the method for measuring open porosity (Archimedes method) specified in JIS R1634:1998 when the porosity is less than 10%, and in accordance with the mercury intrusion method specified in JIS R1655:2003 when the porosity is 10% or more.

[0012] The thickness of the outer periphery 13 is preferably 1.5 mm or more, more preferably 2.0 mm or more, and even more preferably 2.5 mm or more. When the thickness of the outer periphery is above this lower limit, leakage of fluid from the flow synthesis reactor to the outside can be more reliably suppressed. On the other hand, the thickness of the outer periphery 13 is preferably 8.0 mm or less, more preferably 7.0 mm or less, and even more preferably 5.5 mm or less. When the thickness of the outer periphery is below this upper limit, the temperature of the ceramic substrate can be appropriately adjusted in an energy-saving manner during the flow synthesis reaction, thereby improving energy efficiency. The thickness of each part of the ceramic substrate is measured, for example, by cross-sectional observation using an SEM (scanning electron microscope). The thickness is determined by measuring the radial distance from the outermost surface to the inner side surface of the ceramic substrate at multiple points using calipers and taking the average value.

[0013] The density of the outer periphery 13 is set appropriately according to the purpose. For example, the density of the outer periphery 13 is 2.0 g / cm³. ３ ~3.0 g / cm ３ The concentration is preferably 2.5 g / cm³. ３ ~2.8 g / cm ３ The density of each part of the ceramic substrate is measured, for example, by the mercury intrusion method.

[0014] The configuration of the ceramic substrate 1 is not particularly limited, as long as it includes at least an outer periphery 13. The ceramic substrate 1 may consist only of the outer periphery 13 (see Figure 2), or it may include a partition wall 11 in addition to the outer periphery 13 (see Figure 1). As shown in Figure 2, when the ceramic substrate 1 consists only of the outer periphery 13 without a partition wall 11, the ceramic substrate 1 has a single-tube structure, and the inner surface of the outer periphery 13 defines the flow path 14 described above. In other words, the entire internal space of the outer periphery 13 functions as the flow path 14.

[0015] As shown in Figure 3, in one embodiment, the ceramic substrate 1 includes a partition wall 11 in addition to the outer periphery 13. In the illustrated example, the partition wall 11 divides the internal space of the outer periphery 13. As a result, the ceramic substrate 1 has a honeycomb shape. Hereinafter, the ceramic substrate 1 having a honeycomb shape may be referred to as the honeycomb substrate 1a.

[0016] The partition wall 11 is located inside the outer periphery 13. Therefore, the partition wall 11 is sometimes referred to as the inner periphery. The partition wall 11 may be integrated with the outer periphery 13 or it may be a separate part. If the inner periphery is separate from the outer periphery 13, the inner periphery (honeycomb part) may be detachable from the outer periphery 13. This allows only the inner periphery (honeycomb part) to be replaced, and the catalyst and / or cell shape to be changed arbitrarily and appropriately. Therefore, the flow synthesis reactor can be adapted to various chemical reactions. Furthermore, if clogging occurs in the cell, only the inner periphery (honeycomb part) can be replaced, thus reducing running costs. In the illustrated example, the outer periphery 13 and the partition wall 11 are formed integrally.

[0017] In one embodiment, the partition wall 11 constitutes a plurality of cells 12, forming a plurality of flow channels 14 in the internal space of the outer periphery 13. In other words, the illustrated ceramic substrate 1 (honeycomb substrate 1a) has a plurality of cells 12. Each of the plurality of cells 12 extends from the first end face E1 to the second end face E2 of the outer periphery 13 (see Figure 1).

[0018] Cell 12 has any suitable shape in a cross-section perpendicular to the axial direction of the outer periphery 13. Examples of cell cross-sectional shapes include triangles, quadrilaterals, pentagons, polygons with hexagons or more, circles, and ellipses. The cross-sectional shapes and sizes of the cells may all be the same, or at least some may differ. Among such cell cross-sectional shapes, quadrilaterals are preferred, and squares or rectangles are more preferred. When a cell has a quadrilateral cross-sectional shape, the dimension of one side of the cell is, for example, 0.1 cm to 0.5 cm, and preferably 0.2 cm to 0.4 cm.

[0019] In one embodiment, at least a part of the plurality of cells 12 include flow paths 14. In the illustrated example, all of the plurality of cells 12 include flow paths 14. The flow path 14 is a space formed inside the cell 12, and extends from the first end face E1 (inflow end face) to the second end face E2 (outflow end face) similarly to the cell 12 (see FIG. 1). The flow path 14 has any appropriate shape in a cross section perpendicular to the length direction of the ceramic base material 1. Examples of the cross-sectional shape of the flow path 14 include the same cross-sectional shapes as those of the above-described cell 12, preferably a quadrangle, and more preferably a square or a rectangle. All of the cross-sectional shapes and sizes of the flow paths 14 may be the same, or at least a part thereof may be different. The cross-sectional area of each of the plurality of flow paths 14 is, for example, 0.01 cm ２ to 0.25 cm ２ , and preferably 0.04 cm ２ to 0.16 cm ２ .

[0020] The cell density in the honeycomb base material 1a is, for example, 20 cpsi to 900 cpsi, preferably 50 cpsi to 900 cpsi, and more preferably 50 cpsi to 300 cpsi. When the cell density is in such a range, a fluid can be stably supplied to the flow paths included in the cells in a flow synthesis reaction apparatus. In the present specification, "the cell density of a honeycomb base material" means the cell density in a cross-section obtained by cutting the honeycomb base material in a direction perpendicular to the axial direction of the outer peripheral portion, and "cpsi" refers to 6.4516 cm of the cross-section ２ which means the number of cells per (1 square inch).

[0021] In the illustrated example, the partition walls 11 include first partition walls 11a and second partition walls 11b that are orthogonal to each other, and the first partition walls 11a and the second partition walls 11b define the plurality of cells 12. The configuration of the partition walls is not limited to the above-described partition walls 11. The partition walls may include first partition walls extending in the radial direction and second partition walls extending in the circumferential direction, which define the plurality of cells. Further, the honeycomb base material 1a may have a hollow region at its central portion in a cross-section in a direction perpendicular to the axial direction (length direction).

[0022] The thickness of the partition wall 11 is set arbitrarily and appropriately. Typically, the thickness of the partition wall 11 is thinner than the thickness of the outer periphery 13. The thickness of the partition wall 11 is, for example, 0.15 mm to 0.50 mm, and preferably 0.20 mm to 0.50 mm.

[0023] The partition wall 11 may or may not have pores. The porosity of the partition wall 11 is appropriately set according to the purpose. The porosity of the partition wall 11 may be the same as that of the outer periphery 13, or it may be different from that of the outer periphery 13. The porosity of the partition wall 11 is, for example, 50% or less, preferably 40% or less. On the other hand, the porosity of the partition wall 11 is, for example, 0% or more, or for example, 5% or more.

[0024] If the porosity of the partition wall 11 exceeds 0%, the average pore diameter of the partition wall 11 is, for example, 0.4 μm or more, preferably 1.0 μm or more. On the other hand, the average pore diameter of the partition wall 11 is, for example, 18 μm or less, preferably 12 μm or less.

[0025] The density of the partition wall 11 is set appropriately according to the purpose. The density of the partition wall 11 may be the same as the density of the outer periphery 13, or it may be different from the density of the outer periphery 13. For example, the density of the partition wall 11 is 0.32 g / cm³. ３ ~0.80 g / cm ３ The concentration is preferably 0.32 g / cm³. ３ ~0.59 g / cm ３ That is the case.

[0026] Such a ceramic substrate 1 is composed of any suitable ceramic material. Examples of ceramic materials include zirconia-based materials, alumina-titanium carbide composite materials, Si-SiC composite materials, aluminum nitride, aluminum oxide, silicon nitride, silicon carbide, zirconia, cordierite, and mullite. These ceramic materials can be used individually or in combination. Among these ceramic materials, Si-SiC composite materials are preferred. Specific examples of Si-SiC composite materials include, for example, Si-impregnated SiC, Si-impregnated Si-SiC, (Si+Al)-impregnated SiC, metal composite SiC, and recrystallized SiC. These Si-SiC composite materials are described, for example, in Japanese Patent Application Publication No. 2024-131748. The entire description of this publication is incorporated herein by reference.

[0027] Si-SiC composite materials may be porous or dense. A porous Si-SiC composite material is described in detail, for example, in Japanese Patent Publication No. 2002-201082. A dense Si-SiC composite material is described in detail, for example, in Japanese Patent Publication No. 11-035376. The entire descriptions of these publications are incorporated herein by reference.

[0028] In one embodiment, the ceramic substrate 1 is composed of a Si-SiC composite material. In other words, the ceramic substrate 1 contains Si and SiC. Including Si and SiC in the ceramic substrate can improve the thermal conductivity of the ceramic substrate. In particular, if the ceramic substrate contains a dense body of a Si-SiC composite material (preferably Si-impregnated SiC), the thermal conductivity of the ceramic substrate can be further improved.

[0029] When the ceramic substrate 1 is a honeycomb substrate 1a, the outer periphery 13 and the partition wall 11 may be made of the same ceramic material, or they may be made of different ceramic materials. When the outer periphery 13 and the partition wall 11 are made of different ceramic materials, the outer periphery 13 may be made of a dense body of Si-SiC composite material, and the partition wall 11 may be made of a porous body of Si-SiC composite material.

[0030] The thermal conductivity of such a ceramic substrate 1 (outer periphery and / or partition) is, for example, 20 W / m·K or more at 25°C, preferably 30 W / m·K or more, more preferably 100 W / m·K or more, and even more preferably 150 W / m·K or more. Ceramic honeycomb monoliths generally have low thermal conductivity, which makes it difficult for heat from the reaction center to escape to the outer periphery, resulting in the problem of hot spots easily forming. On the other hand, using metal monoliths or high thermal conductivity materials can suppress temperature unevenness, but increases the risk of reaction fluid leaking to the outside through defects and pores in the outer periphery. In this regard, in one embodiment, since the porosity and thickness of the outer periphery of the ceramic substrate are both within the above range, it is possible to suppress leakage of the fluid containing reactants to the outside through the outer periphery. Furthermore, if the thermal conductivity of the ceramic substrate (outer periphery and / or partition) is above this lower limit, sufficient thermal conductivity can be ensured, allowing heat generated from the flow synthesis reaction proceeding in the flow channel to be efficiently transferred to the outer side, and enabling the reaction to proceed stably. Therefore, according to one embodiment of the flow synthesis reactor, even in organic synthesis reactions with a large heat generation, the temperature distribution can be controlled well while reducing the risk of leakage outside the apparatus. On the other hand, the upper limit of the thermal conductivity of the ceramic substrate 1 (outer periphery and / or partition wall) is typically 300 W / m·K. The thermal conductivity is measured, for example, in accordance with JIS R1611.

[0031] Such a ceramic base material 1 may be removable from the flow synthesis reaction apparatus 100. According to this configuration, the ceramic base material can be replaced with one having an appropriate inner peripheral structure depending on the conditions of the reaction carried out in the flow synthesis reaction apparatus and / or the catalyst species that promote the reaction. Furthermore, when clogging occurs in the inner peripheral structure of the ceramic base material, only the ceramic base material can be replaced, so that the running cost can be reduced compared to the case where the entire flow synthesis reaction apparatus is replaced.

[0032] A-2. Catalyst As shown in FIG. 1, a catalyst 2 is typically disposed in a flow path 14 provided in the ceramic base material 1. The catalyst 2 is arbitrarily and appropriately selected according to the organic synthesis reaction performed in the flow synthesis reaction apparatus 100.

[0033] The catalyst 2 typically contains an active component including a metal element. The active component may contain a metal element in a metallic state, may contain a salt of the metal element, or may contain an oxide of the metal element. Examples of the metal element include noble metal elements and transition metal elements. Examples of the noble metal element include platinum, palladium, rhodium, ruthenium, and iridium. Examples of the transition metal element include nickel and cobalt. These metal elements can be used alone or in combination. Among the metal elements, noble metal elements are preferred, and palladium is more preferred. When the catalyst has an active component containing a noble metal element (palladium), various flow synthesis reactions can proceed smoothly.

[0034] The catalyst 2 may contain a carrier in addition to the above-described active component. The carrier is capable of supporting the active component. When the catalyst contains a carrier, the activity of the catalyst can be improved. The carrier is composed of any appropriate inorganic material depending on the application. Examples of the inorganic material include carbon, oxides, carbides, nitrides, sulfides, halides, hydrides, and hydroxides. The inorganic materials can be used alone or in combination. Among such inorganic materials, carbon is preferable.

[0035] Such catalyst 2 has any appropriate shape. Examples of the shape of catalyst 2 include particulate form, bulk form, pellet form, and monolith form. Catalyst 2 is arbitrarily and appropriately disposed in flow path 14 so as to come into contact with a fluid. For example, catalyst 2 may be filled in flow path 14, or may be provided in a layered form on the surface of ceramic substrate 1 that defines flow path 14.

[0036] In one embodiment, catalyst 2 is filled in flow path 14. In the illustrated example, particulate catalyst 2 is filled in flow path 14. When the internal volume of the flow path is taken as 100%, the filling amount of the active component of catalyst 2 in flow path 14 is, for example, 0.5% to 1.0%, and preferably 0.7% to 0.8%.

[0037] In one embodiment, a porous body (not shown) is disposed in flow path 14, and catalyst 2 is filled into flow path 14 in which the porous body is disposed. According to such a configuration, the flow synthesis reaction can proceed more efficiently. The porous body typically has a three-dimensional network structure and is accommodated in flow path 14 in a compressed state. Accordingly, the porous body is in contact with the surface of ceramic substrate 1 that defines flow path 14. The porous body is made of any appropriate material. Examples of the material for the porous body include the ceramic materials described above. The porous body is preferably made of the same ceramic material as ceramic substrate 1 (particularly partition walls 11). The porosity of the porous body is, for example, 85% or more, and preferably 90% or more. On the other hand, the upper limit of the porosity of the porous body is typically 95%. The average pore diameter of the porous body is, for example, 400 µm to 5000 µm, and preferably 1000 µm to 5000 µm.

[0038] A diluent material (not shown) may be filled into flow path 14. Examples of the diluent material include the ceramic materials described above and celite. The diluent material may be used alone or in combination. When catalyst 2 and the diluent material are filled into the flow path, when the internal volume of the flow path is taken as 100%, the total filling amount of catalyst 2 and the diluent material is, for example, 50% to 80%, and preferably 70% to 80%.

[0039] A-3. First end member and second end member In one embodiment, the flow synthesis reactor 100 further comprises a first end member 3 and a second end member 4.

[0040] The first end member 3 is made of any suitable material. Examples of materials for the first end member 3 include stainless steel (SUS) and resin materials, with resin materials being preferred. Specific examples of resin materials include fluororesins such as polytetrafluoroethylene (PTFE); polyolefin resins such as polyethylene and polypropylene; aromatic polyetherketone resins such as polyetheretherketone (PEEK); polyphenylene sulfide (PPS); and elastomers. The materials for the first end member 3 can be used individually or in combination.

[0041] In one embodiment, the first end member 3 is made of a fluororesin. The fluororesin preferably includes an aromatic polyetherketone resin, and more preferably includes PTFE. In the illustrated example, the first end member 3 comprises a main plate 34, a flange portion 35, and a protruding portion 36.

[0042] The main plate 34 faces the first end face E1 in the axial direction of the outer periphery 13. Typically, the main plate 34 has thickness in the axial direction of the outer periphery 13.

[0043] The flange portion 35 protrudes from the peripheral edge of the main plate 34 in the axial direction of the outer circumference 13. The flange portion 35 has a cylindrical shape that extends in the same direction as the outer circumference 13. Typically, the inner surface of the flange portion 35 is formed to conform to the outer shape of the end of the ceramic substrate 1. In the illustrated example, the flange portion 35 has a cylindrical shape (see Figure 3).

[0044] The protrusion 36 is provided on the surface of the main plate 34 opposite to the flange portion 35. The protrusion 36 projects from the main plate 34 in the axial direction of the outer peripheral portion 13. Typically, the protrusion 36 projects from the central portion of the main plate 34.

[0045] The first end member 3 has a supply port 32. Fluid is supplied to the supply port 32 from the outside. The supply port 32 penetrates the first end member 3. In one embodiment, the above-described supply port 32 penetrates the protruding portion 36 and the main body plate 34 in the axial direction of the outer peripheral portion 13. The supply port 32 has any suitable shape in a cross-section in a direction perpendicular to the axial direction of the outer peripheral portion 13. Examples of cross-sectional shapes of the supply port 32 include triangles, quadrilaterals, pentagons, polygons with hexagons or more, circles, and ellipses, with a circle being preferred. The cross-sectional area of ​​the supply port 32 is, for example, 0.008 cm². ２ ~3.14cm ２ The length is preferably 0.08 cm. ２ ~0.157cm ２ That is the case.

[0046] In the illustrated example, the surface of the main plate 34 facing the first end face E1 is inclined to approach the first end face E1 as it moves away from the supply port 32. In other words, the first end member 3 forms a bowl-shaped depression toward the supply port 32 in a cross-section cut in the thickness direction of the main plate 34. This allows the fluid supplied from the supply port to be stably distributed throughout the entire flow path.

[0047] Such a first end member 3 is fixed to the end of the ceramic substrate 1. More specifically, the first end member 3 is fixed to the end of the ceramic substrate 1 on the side of the first end face E1 by any suitable fixing means. In the illustrated example, the flange portion 35 of the first end member 3 is fixed to the ceramic substrate 1 via a sealing member 5 and a retaining plate 6. The retaining plate 6 is fixed to the outer periphery 13 of the ceramic substrate 1. The sealing member 5 is typically made of an elastic fluororesin. With the sealing member 5 sandwiched between the flange portion 35 of the first end member 3 and the retaining plate 6, the flange portion 35 and the retaining plate 6 are connected by a connector (for example, a screw). With this configuration, airtightness between the first end member and the honeycomb substrate can be ensured, and the first end member can be sufficiently fixed to the honeycomb substrate.

[0048] The second end member 4 has the same configuration as the first end member 3, except that it has an outlet 41 instead of a supply port 32. Therefore, a detailed explanation of the second end member 4 will be omitted as appropriate. The outlet 41 can discharge the fluid containing the target compound generated in the flow path 14. The outlet 41 has any suitable shape in the cross-section in a direction perpendicular to the axial direction of the outer circumference 13. An example of the cross-sectional shape of the outlet 41 is the same as that of the supply port 32 described above. The range of the cross-sectional area of ​​the outlet 41 is, for example, the same as that of the cross-sectional area of ​​the supply port 32 described above.

[0049] The second end member 4 is fixed to the end of the ceramic substrate 1 on the second end face E2 side by any suitable fixing means. In the illustrated example, the second end member 4 is fixed to the ceramic substrate 1 via a sealing member 5 and a retaining plate 6, similar to the first end member 3.

[0050] A-4. Filter In one embodiment, the flow synthesis reactor 100 further includes a filter 7 through which the fluid can pass. Typically, the filter 7 is positioned to cover the end face of the outer periphery 13 in the axial direction. In the illustrated example, the flow synthesis reactor 100 includes a filter 7 covering the first end face E1 of the outer periphery 13 (hereinafter sometimes referred to as the first filter 7a) and a filter 7 covering the second end face E2 of the outer periphery 13 (hereinafter sometimes referred to as the second filter 7b). When the flow synthesis reactor is equipped with the first filter, the fluid can be appropriately diffused into the flow path and variations in the amount of fluid passing through the flow path can be suppressed. When the flow synthesis reactor is equipped with the second filter, the outflow of catalyst from the flow path can be suppressed.

[0051] Each of the filters 7 (the first filter 7a and the second filter 7b) typically has a plate shape with thickness in the axial direction of the outer periphery 13.

[0052] In one embodiment, the filter 7 has the same shape and size as the outer circumference 13 when viewed from the axial direction of the outer circumference 13.

[0053] The thickness of the filter 7 (the dimension in the axial direction of the outer circumference) is, for example, 1.0 mm or more, preferably 1.5 mm or more, more preferably 2.0 mm or more, and even more preferably 3.0 mm or more. On the other hand, the thickness of the filter 7 is, for example, 10.0 mm or less, preferably 5.0 mm or less. When the filter thickness is within this range, the fluid can be stably supplied to the flow path.

[0054] The filter 7 is typically composed of a porous material having continuous pores. The average pore diameter in the filter 7 is, for example, 1 μm or more, preferably 5 μm or more, and more preferably 10 μm or more. On the other hand, the average pore diameter in the filter 7 is, for example, 50 μm or less, and preferably 30 μm or less. The porosity of the filter 7 is, for example, 35% to 60%, and preferably 35% to 40%. The pore diameter of the filter 7 may be substantially uniform throughout the filter 7, or it may vary in parts within the filter 7.

[0055] The filter 7 is made of any suitable material. Typical materials for the filter 7 include resin materials. Specific examples of resin materials include fluororesins such as polytetrafluoroethylene (PTFE); polyolefin resins such as polyethylene and polypropylene; aromatic polyetherketone resins such as polyetheretherketone (PEEK); polyphenylene sulfide (PPS); and elastomers. The materials for the filter 7 can be used individually or in combination. In one embodiment, the filter 7 is made of a fluororesin. The fluororesin preferably includes PTFE.

[0056] In the illustrated example, the relative movement of the first filter 7a with respect to the outer periphery 13 is restricted by the first end member 3. The relative movement of the second filter 7b with respect to the outer periphery 13 is restricted by the second end member 4.

[0057] With this flow synthesis reactor 100, despite its simple configuration, leakage of the fluid containing the reactants to the outside can be suppressed. Therefore, the flow synthesis reaction can be carried out without housing the ceramic substrate 1 in a housing that does not allow fluid to permeate. As a result, the flow synthesis reaction can be carried out efficiently despite its simple configuration.

[0058] Furthermore, as shown in Figures 4 and 5, the flow synthesis reactor 100 may further include a temperature control member 8 configured to temperature control the flow path 14. The temperature control member 8 is typically provided on the outer circumferential surface of the outer circumferential portion 13. This allows the temperature control member to temperature control the flow path via the outer circumferential portion. Examples of the temperature control member 8 include a cooling jacket flow path and an electric heater (typically an electronic coolant: Peltier element). As shown in Figure 4, in one embodiment, the flow synthesis reactor 100 includes an electric heater 81 as the temperature control member 8. The electric heater 81 is configured to temperature control the flow path 14 via the outer circumferential portion 13 when a voltage is applied. As shown in Figure 5, in another embodiment, the flow synthesis reactor 100 includes a cooling jacket 82 as the temperature control member 8. The cooling jacket 82 has a medium flow path through which a cooling medium passes. The cooling jacket 82 is configured to temperature control the flow path 14 via the outer circumferential portion 13 when the cooling medium passes through the medium flow path.

[0059] Furthermore, the flow synthesis reactor 100 may include a plurality of modules, each comprising the ceramic substrate 1 and the catalyst 2 described above. The plurality of modules may be connected in series in multiple stages or in parallel. This allows for the scale-up of the flow synthesis reactor. When multiple modules are connected, connecting modules in different temperature ranges allows for appropriate temperature control of the flow path 14.

[0060] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0061] <<Example 1>> A clay containing SiC powder was extruded and then dried to prepare a dried body having a cylindrical shape as shown in Figure 2. A material powder containing Si powder was press-molded and then dried to obtain a Si supply body. Next, with the Si supply body in contact with the dried body, it was heated at 1500°C for 4 hours to impregnate the dried body with molten metal containing Si. The amount of molten Si metal was 40 parts by mass per 100 parts by mass of the dried body. In this way, a ceramic substrate composed of a Si-SiC composite material (Si-impregnated SiC) was prepared. The ceramic substrate had a single-tube shape (more specifically, a cylindrical shape). In other words, the ceramic substrate consisted only of an outer circumference having a cylindrical shape. Hereinafter, the ceramic substrate having a cylindrical shape may be referred to as the cylindrical substrate. The inner diameter of the cylindrical substrate was 30 mm, and the internal volume of the cylindrical substrate was 100 mmL. The thickness, porosity, and thermal conductivity of the cylindrical substrate are shown in Table 1.

[0062] Next, a palladium-based catalyst and Celite (a diluting agent) were packed into the interior of the cylindrical substrate. The palladium-based catalyst contained an active component containing palladium and a carbon support that carried the active component. The palladium content in the palladium-based catalyst was 10% by mass. When the internal volume of the cylindrical substrate was set to 100%, the amount of palladium-based catalyst packed in was 7%, and the total amount of palladium-based catalyst and diluting agent packed in was 70%.

[0063] Next, the first end member shown in Figure 1 was prepared. The first end member was made of PEEK. The cross-sectional area of ​​the supply port was 0.01 cm². ２ Subsequently, the first end member was fixed to the end of the cylindrical base material on the first end face side. More specifically, the first end member was fixed to the end of the honeycomb base material using a sealing member, a retaining plate, and screws. Similarly, the second end member, made of PEEK, was fixed to the end of the honeycomb base material on the second end face side. The cross-sectional area of ​​the discharge port was 0.03 cm². ２ Therefore, a flow synthesis reactor was manufactured.

[0064] <<Example 2>> A flow synthesis reactor was manufactured in the same manner as in Example 1, except that the thickness of the cylindrical base material was changed to 10.0 mm.

[0065] <<Example 3>> A flow synthesis reactor was manufactured in the same manner as in Example 1, except that the porosity of the cylindrical substrate was changed to 10.0% and the thickness of the cylindrical substrate was changed to 1.0 mm.

[0066] <<Example 4>> A flow synthesis reactor was manufactured in the same manner as in Example 1, except that a porous body was placed inside a cylindrical substrate. The porous body was in contact with the inner surface of the cylindrical substrate in a compressed state. The dimensions of the porous body in the axial direction of the cylindrical substrate were 90 mm. The porous body was made of SiC. The porosity of the porous body was 90%, and the average pore diameter was 2000 μm.

[0067] <<Example 5>> A clay containing SiC powder was extruded and then dried to prepare a dried body having the honeycomb shape shown in Figure 1. A material powder containing Si powder was press-molded and then dried to obtain a Si supply body. Next, with the Si supply body in contact with the dried body, it was heated at 400°C for 4 hours to impregnate the dried body with molten metal containing Si. The amount of molten Si metal was 35 parts by mass per 100 parts by mass of the dried body. In this way, a ceramic substrate composed of a Si-SiC composite material (Si-impregnated SiC) was prepared. The ceramic substrate had a honeycomb shape. More specifically, the ceramic substrate had a cylindrical outer periphery and partition walls located inside the outer periphery. The partition walls defined multiple cells. Hereinafter, the ceramic substrate having a honeycomb shape may be referred to as a honeycomb substrate. In the honeycomb substrate, the cell density was 20 cpsi, the inner diameter of the outer periphery was 30 mm, and the total internal volume of the multiple cells was 100 mmL. The thickness, porosity, and thermal conductivity of the outer periphery are shown in Table 1.

[0068] Next, the same palladium-based catalyst and Celite (diluting agent) as in Example 1 were packed into the interiors of multiple cells in the honeycomb substrate. When the total internal volume of the multiple cells was set to 100%, the amount of palladium-based catalyst packed was 7%, and the total amount of palladium-based catalyst and diluting agent packed was 70%.

[0069] Subsequently, in the same manner as in Example 1, the first end member was fixed to the end on the first end face side of the honeycomb substrate, and the second end member was fixed to the end on the second end face side of the honeycomb substrate. A flow synthesis reactor was then manufactured.

[0070] <<Example 6>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that a porous material similar to that in Example 4 was placed inside multiple cells, and the cell density of the honeycomb substrate was changed to 200 cpsi.

[0071] <<Comparative Example 1>> A flow synthesis reactor was manufactured in the same manner as in Example 1, except that a cylindrical dried body shown in Figure 2 was heated without contact with the Si supply to prepare a ceramic substrate.

[0072] <<Comparative Example 2>> A metal tube made of SUS material was filled with the same palladium-based catalyst and Celite (splitting agent) as in Example 1. The metal tube consisted only of the outer periphery made of SUS material. The thickness, porosity, and thermal conductivity of the metal tube are shown in Table 1 as the thickness, porosity, and thermal conductivity of the outer periphery.

[0073] <Evaluation: Flow Synthesis A> 0.5 mmol of bromoacetone, 0.6 mmol of phenylboronic acid, and 1.0 mmol of sodium hydroxide were added to a mixed solvent of dioxane and water (dioxane:water = 1:3) and stirred to prepare a starting material solution. Next, the flow synthesis reactors prepared in Examples 1-6 and Comparative Examples 1 and 2 were heated to 80°C, and the starting material solution was supplied to the feed port at a flow rate of 0.5 mL / min. Subsequently, the effluent containing the target compound, acetylbiphenyl, was collected from the outlet. Next, the solvent was removed from the collected effluent to obtain a crude containing the reaction substrate (reactants) and / or reaction product. Next, the crude was dissolved in deuterated chloroform and subjected to a nuclear magnetic resonance apparatus ( １ The yields of the reaction substrate (reactants) and reaction products were calculated based on the internal standard, tetrachloroethane, using 1H-NMR. The results are shown in Table 1.

[0074] <<Example 7>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that the porosity of the honeycomb substrate was changed to 3.0% and the thickness of the honeycomb substrate was changed to 1.0 mm.

[0075] <<Example 8>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that the porosity of the honeycomb substrate was changed to 3.0% and the thickness of the honeycomb substrate was changed to 3.0 mm.

[0076] <<Example 9>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that the porosity of the honeycomb substrate was changed to 3.0% and the thickness of the honeycomb substrate was changed to 5.0 mm.

[0077] <<Example 10>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that the porosity of the honeycomb substrate was changed to 5.0% and the thickness of the honeycomb substrate was changed to 7.0 mm.

[0078] <<Comparative Example 3>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that the porosity of the honeycomb substrate was changed to 2.0% and the thickness of the honeycomb substrate was changed to 0.7 mm.

[0079] <<Comparative Example 4>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that the porosity of the honeycomb substrate was changed to 12.0% and the thickness of the honeycomb substrate was changed to 10 mm.

[0080] <Evaluation: Leak Test> In the flow synthesis reactors manufactured in Examples 7-10 and Comparative Examples 3 and 4, tubes were airtightly connected to the first end member and the second end member, respectively. Next, the flow synthesis reactors with the connected tubes were immersed in water contained in a water tank. Then, pressurized air at 0.8 MPa was supplied from the tube connected to the first end member to the supply port, and it was checked whether there was any air leakage from the flow synthesis reactor. The results are shown in Table 2.

[0081] <<Example 11>> A flow synthesis reactor was manufactured in the same manner as in Example 1, except that the porosity of the cylindrical substrate was changed to 2% and the thickness of the cylindrical substrate was changed to 3.0 mm.

[0082] <<Example 12>> A flow synthesis reactor was manufactured in the same manner as in Example 5, except that the porosity of the honeycomb substrate was changed to 3%.

[0083] <<Comparative Example 5>> A flow synthesis reactor was manufactured in the same manner as in Example 11, except that the material of the cylindrical base material was changed to SUS316L.

[0084] <<Comparative Example 6>> A flow synthesis reactor was manufactured in the same manner as in Example 12, except that the material of the honeycomb substrate was changed to SUS316L.

[0085] <Evaluation: Flow Synthesis B> 1-ethyl-4-nitrobenzene was supplied at a flow rate of 0.1 mL / min to the feed port of the flow synthesis reactor prepared in Examples 11, 12 and Comparative Examples 5, 6, and hydrogen gas was supplied at a flow rate of 60.0 mL / min. Subsequently, the effluent containing the target compound, 4-ethylaniline, was collected from the outlet. Next, the solvent was removed from the collected effluent to obtain a crude containing the reaction substrate (reactants) and / or reaction product. The crude was then dissolved in deuterated chloroform and subjected to a nuclear magnetic resonance apparatus ( １The yields of the reaction substrate (reactants) and reaction products were calculated based on the internal standard, tetrachloroethane, using 1H-NMR. The results are shown in Table 3. The temperature in the flow channel of the flow synthesis reactor was measured using a multi-point thermocouple from the start to the stop of the supply of 1-ethyl-4-nitrobenzene. More specifically, the temperature was measured at a first position 20 mm from the first end face of the ceramic substrate and at a second position 50 mm from the first end face of the ceramic substrate in the flow channel of the flow synthesis reactor. The highest temperature among these is shown in Table 3.

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[0088]

[0089] <Evaluation> As shown in Tables 1 to 3, in the examples where the porosity of the outer periphery of the ceramic substrate is 0% to 10% and the thickness is 1 mm to 10 mm, it can be seen that leakage of the fluid containing the reactants to the outside of the flow synthesis reactor can be suppressed, and the desired flow synthesis reaction can proceed efficiently. On the other hand, leakage and a decrease in yield were observed in the comparative examples. Furthermore, as is clear from Table 3, Examples 11 and 12, in which the substrate contains Si and SiC, have superior heat removal properties and improved temperature uniformity in the flow path compared to Comparative Examples 5 and 6, in which the substrate is made of SUS. More specifically, comparing Example 11 and Comparative Example 5, in which the substrates have a single-tube structure, it was confirmed that the maximum temperature in the flow path of Example 11 was lower than the maximum temperature in the flow path of Comparative Example 5, and comparing Example 12 and Comparative Example 6, in which the substrates have a honeycomb structure, it was confirmed that the maximum temperature in the flow path of Example 12 was lower than the maximum temperature in the flow path of Comparative Example 6.

[0090] The flow synthesis reactor according to the embodiment of the present invention can safely and efficiently carry out various flow synthesis reactions, particularly organic synthesis reactions with high heat generation, and therefore has industrial applicability in the fields of pharmaceuticals, agrochemicals, and fine chemicals.

[0091] 1 Ceramic substrate 1a Honeycomb substrate 13 Outer periphery 14 Flow channel 100 Flow synthesis reactor

Claims

1. A flow synthesis reactor comprising: a ceramic substrate having a cylindrical outer periphery, wherein the internal space of the outer periphery includes a channel through which a fluid containing reactants is supplied; and a catalyst capable of promoting the chemical reaction of the reactants, which is arranged to be in contact with the fluid supplied to the channel, wherein the porosity of the outer periphery is 0% or more and 10% or less, and the thickness of the outer periphery is 1 mm or more and 10 mm or less.

2. The flow synthesis reactor according to claim 1, wherein the thermal conductivity of the ceramic substrate is 30 W / m·K or higher.

3. The flow synthesis reactor according to claim 1 or 2, wherein the ceramic substrate further comprises partition walls provided on the inner side of the outer periphery, which constitute a plurality of cells, and at least a portion of the plurality of cells includes the flow channel.

4. The flow synthesis reactor according to claim 1 or 2, wherein the ceramic substrate comprises Si and SiC.

5. The flow synthesis reactor according to claim 1 or 2, wherein the catalyst comprises an active component containing a noble metal element and a carrier supporting the active component.

6. The flow synthesis reactor according to claim 5, wherein the noble metal element includes palladium.

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