Chemical reaction apparatus and chemical reaction method

Abstract

To provide a chemical reaction apparatus and a chemical reaction method capable of more efficiently promoting a chemical reaction compared with a conventional chemical rection apparatus and a chemical reaction method.SOLUTION: A chemical reaction apparatus includes: a millimeter wave oscillator that oscillates millimeter waves in a range of 20 GHz or more and 40 GHz or less; a reactor that contains a solid catalyst with millimeter wave absorption properties and holds raw materials inside; and a transmission structure that amplifies and transmits millimeter waves in one direction from the millimeter wave oscillator to the reactor. The chemical reaction method includes the steps of: using the chemical reaction apparatus to generate millimeter waves by the millimeter wave oscillator, supplying the millimeter waves to the solid catalyst inside the reactor via the transmission structure; and housing the raw materials inside the reactor to bring the solid catalyst and raw materials into contact with each other.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a chemical reaction device and a chemical reaction method. [Background technology]

[0002] WO 2015 / 105080 (Patent Document 1) discloses a chemical reaction apparatus including a microwave-transparent reaction tube through which a gas flows, a fixed-bed catalyst layer having microwave absorbing properties arranged inside the reaction tube, a jacket that surrounds the outer circumferential surface of the reaction tube corresponding to the catalyst layer and partially absorbs and partially transmits microwaves, and a microwave generator that irradiates microwaves to the jacket. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2015 / 105080 Summary of the Invention [Problem to be solved by the invention]

[0004] The chemical reaction device disclosed in International Publication WO 2015 / 105080 (Patent Document 1) promotes chemical reactions by irradiating a catalyst with microwaves to enhance catalytic activity. However, there has been a demand for the development of a chemical reaction device and a chemical reaction method that can further promote chemical reactions.

[0005] Therefore, an object of the present disclosure is to provide a chemical reaction apparatus and a chemical reaction method that can promote a chemical reaction more efficiently than conventional chemical reaction apparatuses and chemical reaction methods. [Means for solving the problem]

[0006] [1] A chemical reaction apparatus according to one embodiment of the present disclosure includes a millimeter wave oscillator that oscillates millimeter waves of 20 GHz or more and 40 GHz or less, a reactor that contains a solid catalyst having millimeter wave absorption properties therein and accommodates a raw material, and a transmission structure that amplifies and transmits the millimeter waves in one direction from the millimeter wave oscillator to the reactor.

[0007] [2] In the chemical reaction apparatus of [1] above, the reactor may be a cavity resonator.

[0008] [3] In the chemical reaction device of [1] or [2] above, the transmission structure may include a circulator connected to the millimeter-wave oscillator, a bidirectional coupler connected to the circulator, an EH tuner connected between the bidirectional coupler and the reactor, and a reflected wave power sensor and a forward wave power sensor connected to the bidirectional coupler.

[0009] [4] In the chemical reaction device according to [3] above, the transmission structure may further include a flexible waveguide connected between the bidirectional coupler and the EH tuner.

[0010] [5] The chemical reaction apparatus according to [1] or [2] above may further include a temperature measuring device for measuring an internal temperature of the reactor.

[0011] [6] The chemical reaction apparatus according to [1] or [2] above may further include a detector for detecting chemical reaction products of the raw materials in the reactor.

[0012] [7] In the chemical reaction apparatus according to the above item [1] or [2], the solid catalyst may include a support and metal particles supported on the support.

[0013] [8] In the chemical reaction device according to [7] above, the carrier can have a lower millimeter wave absorption property than the metal fine particles.

[0014] [9] In the chemical reaction apparatus according to [7] above, the metal fine particles may have a particle size of 1 nm or more and 100 nm or less.

[0015]

[10] A chemical reaction method according to another aspect of the present disclosure includes the steps of using the chemical reaction apparatus of [1] or [2] above to generate millimeter waves using the millimeter wave oscillator and supplying the millimeter waves to the solid catalyst inside the reactor via the transmission structure, and placing the raw material inside the reactor and contacting the solid catalyst with the raw material.

[0016]

[11] Furthermore, a chemical reaction method according to another aspect of the present disclosure includes the steps of using the chemical reaction apparatus of [3] above to generate millimeter waves using the millimeter wave oscillator and supplying the millimeter waves to the solid catalyst inside the reactor via the circulator, the bidirectional coupler, and the EH tuner, and placing the raw material inside the reactor and contacting the solid catalyst with the raw material. Effect of the Invention

[0017] According to the present disclosure, it is possible to provide a chemical reaction apparatus and a chemical reaction method that can promote a chemical reaction more efficiently than conventional chemical reaction apparatuses and chemical reaction methods. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of a chemical reaction device according to an embodiment of the present disclosure. [Diagram 2] FIG. 13 is a partially enlarged schematic view showing another example of a portion of a transmission structure in a chemical reaction device according to an embodiment of the present disclosure. [Diagram 3] FIG. 1 is a schematic diagram showing an example of a solid catalyst included in a chemical reaction device according to an embodiment of the present disclosure. [Figure 4] 1 is a graph showing the relationship between the frequency of an electromagnetic wave supplied to a solid catalyst and the maximum temperature reached by the solid catalyst in a chemical reaction device according to an embodiment of the present disclosure. [Diagram 5]13 is a graph showing the relationship between the output of electromagnetic waves and the temperature of metal particles of a solid catalyst in a chemical reaction method according to another embodiment of the present disclosure and other chemical reaction methods. [Figure 6] 10 is a graph showing the relationship between the heat or electromagnetic waves supplied and the maximum hydrogen generation rate in the chemical reaction method according to another embodiment of the present disclosure and other chemical reaction methods, where (A) shows the case where heat is supplied by a thermogravimetric analyzer (hereinafter also referred to as TG), (B) shows the case where 2.45 GHz microwaves are supplied, and (C) shows the case where 30 GHz millimeter waves are supplied. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] [Embodiment 1: Chemical reaction device] 1 to 3, a chemical reaction device 10 according to an embodiment of the present disclosure includes a millimeter wave oscillator 11 that oscillates millimeter waves 11m having a frequency of 20 GHz or more and 40 GHz or less, a reactor 19 that contains a solid catalyst 19c having millimeter wave absorbing properties therein and that accommodates a raw material 20 therein, and a transmission structure 12 that amplifies and transmits the millimeter waves in one direction from the millimeter wave oscillator 11 to the reactor 19.

[0020] The chemical reaction device 10 of this embodiment includes the above-mentioned millimeter wave oscillator 11, reactor 19, and transmission structure 12, and therefore can efficiently supply millimeter waves 11m to the millimeter wave absorbing solid catalyst 19c contained inside the reactor 19, thereby efficiently activating the solid catalyst 19c and promoting the chemical reaction.

[0021] [Millimeter wave oscillator] The millimeter wave oscillator 11 included in the chemical reaction device 10 of this embodiment oscillates millimeter waves 11m of 20 GHz or more and 40 GHz or less. A millimeter wave is usually defined as an electromagnetic wave with a wavelength of 1 mm or more and 10 mm, that is, a frequency of 30 GHz or more and 300 GHz or less. However, an electromagnetic wave with a frequency of 20 GHz or more and less than 30 GHz has a longer wavelength than the millimeter wave defined above, but has the same characteristics as the millimeter wave defined above as an electromagnetic wave, and is therefore included in the millimeter wave 11m in this application. In addition, the frequency is set to 40 GHz or less from the viewpoint of ensuring a sample size sufficient for supplying the millimeter wave 11m to the solid catalyst 19c inside the reactor 19 of the chemical reaction device 10 of this embodiment.

[0022] The millimeter wave oscillator 11 includes an oscillation source 111. The oscillation source 111 may be a semiconductor or a magnetron, and any oscillation method may be used. However, from the viewpoint of obtaining a single mode resonance described later, the oscillation source 111 is preferably yttrium iron garnet (YIG) or a semiconductor.

[0023] The millimeter wave oscillator 11 may further include at least one amplifier 112. By including at least one amplifier 112, the millimeter wave can be amplified to increase the maximum output to 10 W or more. As shown in Fig. 1, the millimeter wave is preliminarily amplified by a preamplifier 112a and further amplified by a main amplifier 112b, so that a maximum output of 10 W or more can be efficiently obtained. Note that if a maximum output of 10 W or more can be obtained, one amplifier is sufficient.

[0024] [Reactor] The reactor 19 included in the chemical reaction apparatus 10 of this embodiment contains a millimeter wave absorbing solid catalyst 19c therein, and contains raw material 20. Inside the reactor 19, the solid catalyst 19c, which has been activated by absorbing the millimeter waves 11m transmitted by a transmission structure described below, comes into contact with the contained raw material 20, and the raw material undergoes a chemical reaction to produce a chemical reaction product 22.

[0025] (Solid catalyst) The solid catalyst 19c contained in the reactor 19 is not particularly limited as long as it has millimeter wave absorption properties and catalytic activity for the chemical reaction of the raw material, and metals, metal oxides, and the like are suitable. Here, the millimeter wave absorption properties refer to the property of absorbing millimeter waves, generating heat, and activating the material. In addition, the metal includes alloys, and the metal oxide includes composite oxides containing two or more metals. Here, the type of metal or metal oxide that serves as a catalyst varies depending on the type of chemical reaction of the raw material. For example, a metal such as Pt is suitable as a catalyst for the thermochemical decomposition reaction of biomass containing lignocellulose. In addition, the solid catalyst may be porous from the viewpoint of increasing the contact efficiency with the raw material. An example of a porous catalyst is zeolite.

[0026] Furthermore, as shown in FIG. 3, the solid catalyst 19c may include a carrier 19cs and metal fine particles 19cc supported on the carrier 19cs from the viewpoint of efficiently activating the solid catalyst. There is no particular limitation on the carrier 19cs as long as it can support the metal fine particles. Here, from the viewpoint of efficiently activating the metal fine particles 19cc supported on the carrier 19cs in the solid catalyst 19c, it is preferable that the carrier 19cs has a lower millimeter wave absorption than the metal fine particles 19cc. For example, it is preferable to use SiO2 (silicon dioxide) as the carrier and Pt as the metal fine particles. Moreover, from the viewpoint of efficiently activating the metal fine particles and increasing the contact efficiency with the raw material, the particle diameter of the metal fine particles 19cc is preferably 1 nm or more and 100 nm or less.

[0027] (raw materials) The raw material 20 contained inside the reactor 19 is not particularly limited as long as it reacts with the solid catalyst 19c activated by absorbing millimeter waves 11m to produce a reaction product. For example, cellulose that generates hydrogen gas, a reaction product of a pyrolysis reaction, when it comes into contact with a solid catalyst containing Pt (platinum) activated by absorbing millimeter waves can be used.

[0028] (cavity resonator) In the chemical reaction device 10 of this embodiment, the reactor 19 can be a cavity resonator. The cavity resonator further amplifies the millimeter wave 11m amplified and transmitted by the transmission structure 12 described below through resonance, and supplies the amplified millimeter wave 11m to a solid catalyst 19c having millimeter wave absorption properties inside the reactor 19, thereby efficiently heating and activating the solid catalyst 19c. The cavity resonator serving as the reactor 19 may be either a TE mode or a TM mode. Here, from the viewpoint of more efficiently activating the solid catalyst 19c, the cavity resonator is preferably a TM mode.

[0029] [Transmission Structure] The transmission structure 12 included in the chemical reaction device 10 of this embodiment is not particularly limited in structure, as long as it has a structure for amplifying and transmitting the millimeter wave 11m in one direction from the millimeter wave oscillator 11 to the reactor 19. The transmission structure 12 may include, for example, a circulator 13 connected to the millimeter wave oscillator 11, a bidirectional coupler 15 connected to the circulator 13, an EH tuner 17 connected between the bidirectional coupler 15 and the reactor 19, and a reflected wave power sensor 152 and a traveling wave power sensor 154 connected to the bidirectional coupler 15.

[0030] (Circulator) The circulator 13 included in the transmission structure 12 of the chemical reaction device 10 of this embodiment acts as an isolator that transmits the millimeter wave 11m oscillated from the millimeter wave oscillator 11 to the bidirectional coupler 15 in only one direction.

[0031] (bidirectional coupler) The bidirectional coupler 15 included in the transmission structure 12 of the chemical reaction device 10 of this embodiment has four ports: an input port, an output port, a coupling forward port, and a coupling reflection port, and has the function of extracting millimeter waves in one direction (the direction of propagation).

[0032] (Reflected wave power sensor and progressive wave power sensor) The reflected wave power sensor 152 and the forward wave power sensor 154 included in the transmission structure 12 of the chemical reaction device 10 of this embodiment are connected to the coupled forward port and the coupled reflected port of the bidirectional coupler 15, respectively, and have the function of monitoring the power of the millimeter wave (reflected wave) in the direction opposite to the forward direction and the millimeter wave (forward wave) in the forward direction.

[0033] (EH tuner) The EH tuner 17 included in the transmission structure 12 of the chemical reaction device 10 of this embodiment has the effect of minimizing the reflected wave power by adjusting the E tuner, and further minimizing the reflected wave power by adjusting the H tuner to achieve an approximately matched state, thereby maximizing the traveling wave of the millimeter wave and supplying it to the solid catalyst 19c in the reactor 19.

[0034] (flexible waveguide) 1 and 2, the transmission structure 12 of the chemical reaction device 10 of this embodiment may further include a flexible waveguide 16 (shown in FIG. 2) connected between the bidirectional coupler 15 and the EH tuner 17. By including the flexible waveguide 16, the chemical reaction device 10 can increase the degree of freedom in arranging each device.

[0035] (temperature measuring device) Referring to FIG. 1, the chemical reaction apparatus 10 of this embodiment may further include a temperature measuring device 192 for measuring the temperature inside the reactor 19. By including such a temperature measuring device 192, the chemical reaction apparatus 10 enables supply of millimeter waves to the solid catalyst and / or in situ temperature measurement of the chemical reaction of the raw materials. Examples of such a temperature measuring device 192 include an infrared temperature measuring device and temperature measurement by X-ray absorption fine structure (hereinafter also referred to as XAFS) analysis. The infrared temperature measuring device can measure the temperature of the entire solid catalyst, and the XAFS analysis can measure the temperature of metal particles in the solid catalyst.

[0036] (Detector) 1, the chemical reaction apparatus 10 of this embodiment may further include a detector 194 for detecting a chemical reaction product 22 of the raw material 20 in the reactor 19. By including such a detector 194, the chemical reaction apparatus 10 enables the supply of millimeter waves to the solid catalyst and the in situ detection of the chemical reaction product of the raw material chemical reaction. Examples of such a detector 194 include a mass spectrometry detector (hereinafter also referred to as an MS detector), gas chromatography, and the like.

[0037] [Embodiment 2: Chemical reaction method] Referring to FIG. 1, a chemical reaction method according to another embodiment of the present disclosure includes a step (hereinafter also referred to as step A) of generating millimeter waves 11m by a millimeter wave oscillator 11 using a chemical reaction device 10 according to embodiment 1, and supplying the millimeter waves 11m to a solid catalyst 19c inside a reactor 19 via a transmission structure 12, and a step (hereinafter also referred to as step B) of accommodating a raw material 20 inside the reactor 19 and contacting the solid catalyst 19c with the raw material 20. Here, it is sufficient that at least a part of the time when steps A and B are performed is the same, and the start and / or end of the steps do not necessarily have to be the same. From the viewpoint of efficiently promoting the chemical reaction of the raw material, it is preferable that as many parts as possible of the time when steps A and B are performed are the same, and it is preferable that the start and end of the steps are the same as much as possible.

[0038] (Step A) Step A included in the chemical reaction method of this embodiment is a step of generating millimeter waves 11m by the millimeter wave oscillator 11 and supplying the millimeter waves 11m to the solid catalyst 19c inside the reactor 19 via the transmission structure 12. By such step A, the solid catalyst 19c is efficiently heated by the millimeter waves 11m and efficiently activated. Since the transmission structure 12 in this embodiment is the same as the transmission structure 12 described in the first embodiment, it will not be repeated here. Therefore, step A may be, for example, a step of generating millimeter waves 11m by the millimeter wave oscillator 11 of the chemical reaction device 10 and supplying the millimeter waves 11m to the solid catalyst 19c inside the reactor 19 via the circulator 13, the bidirectional coupler 15, and the EH tuner 17. Here, the action of each device of the chemical reaction device 10 in this embodiment is the same as the action of each device of the chemical reaction device 10 described in the first embodiment, so it will not be repeated here.

[0039] (Step B) Step B included in the chemical reaction method of the present embodiment is a step of storing the raw material 20 inside the reactor 19 and contacting the solid catalyst 19c with the raw material 20. By such step B, the efficiently activated solid catalyst 19c is brought into contact with the raw material 20, and the chemical reaction of the raw material 20 can be efficiently promoted.

[0040] With reference to FIG. 1, in the step B, the method of "accommodating the raw material 20 inside the reactor 19" is such that, when the raw material 20 is a solid 20s, it can be accommodated inside the reactor 19 as a solid 20s, and when the raw material 20 is a fluid 20f, it can be accommodated by supplying it to the reactor 19 as a fluid 20f. In addition, in the step B, the method of "contacting the solid catalyst 19c with the raw material 20" is such that, when the raw material 20 is a solid 20s, a carrier fluid is supplied to the reactor 19 as the fluid 20f, so that the solid catalyst 19c can be efficiently contacted with the raw material 20 of the solid 20s, and when the raw material 20 is a fluid 20f, the fluid 20f is supplied to the reactor 19, so that the solid catalyst 19c can be efficiently contacted with the raw material 20 of the fluid 20f. Here, the fluid includes gas and liquid, and the carrier fluid includes carrier gas and carrier liquid. The carrier fluid used is one that has low reactivity with the solid catalyst, and preferably has no reactivity. EXAMPLES

[0041] (Reference example 1) Using the chemical reaction apparatus of embodiment 1, the solid catalyst Pt (5 mass%) / SiO2, in which Pt (metal fine particles) is supported at 5 mass% on SiO2 (support) inside the reactor, was supplied with electromagnetic waves having the frequencies shown in Fig. 4, and the maximum temperature (°C) of the solid catalyst was measured with an infrared temperature measuring device. The results are shown in Fig. 4.

[0042] Figure 4 shows that millimeter waves can heat and activate solid catalysts more efficiently than microwaves.

[0043] (Reference example 2) Using the chemical reaction apparatus of embodiment 1, a solid catalyst Pt (5 mass%) / SiO2 in which Pt (metal fine particles) is supported at 5 mass% on SiO2 (support) inside the reactor was supplied with microwaves of 2.45 GHz x (0 W, 5 W, 20 W, 40 W, or 80 W) or millimeter waves of 30 GHz x (0 W, 1 W, 2 W, 4 W, or 6 W) for 3 to 5 minutes, and the temperature (°C) of the metal fine particles in the solid catalyst was measured using XAFS for each example. The results are shown in Figure 5.

[0044] Figure 5 shows that compared with 2.45 GHz microwaves, 30 GHz millimeter waves can heat the metal particles in the solid catalyst to a higher temperature with lower output and activate them more effectively.

[0045] Example 1 Using the chemical reaction apparatus of the first embodiment, 50 mg of solid catalyst Pt (10% by mass) / SiO2, in which 10% by mass of Pt (metal fine particles) is supported on SiO2 (support) inside the reactor, was (A) heated by a TG measurement device, (B) supplied with microwaves of 2.45 GHz x 40 W, or (C) supplied with millimeter waves of 30 GHz x 5 W. Simultaneously with the heating, supply of microwaves, or supply of millimeter waves to the solid catalyst, 250 mg of solid cellulose was placed inside the reactor as a raw material, and Ar (argon) gas, which is a carrier gas for the fluid, was supplied at (A) 100 mL (milliliter) / min, (B) 20 mL / min, or (C) 10 mL. That is, the mass ratio of raw material to solid catalyst was 5:1. The amount of hydrogen (H2) gas, which is the main component of the chemical reaction product obtained by thermal decomposition of the raw material cellulose, was detected by an MS detector, and the maximum hydrogen generation rate was calculated. The results are shown in FIG. 6.

[0046] The heating rate in the case of (A) was 20°C / min, while the heating rate in the case of (B) was 18°C / sec, and in the case of (C) was 100°C / sec, which was significantly faster. This shows that microwaves can heat solid catalysts more efficiently than heat conduction, and millimeter waves can heat solid catalysts more efficiently than microwaves. Furthermore, in the case of (A), the temperature at which the production rate of H2 gas, the main component of the pyrolysis reaction product of cellulose, was maximized was 380°C, while in the case of (B), the maximum temperature was 300°C, and in the case of (C), the maximum temperature was 250°C. The reaction temperature in (B) was 80°C lower than that in (A), and the reaction temperature in (C) was 50°C lower than that in (B). Also, referring to Figure 6, the maximum hydrogen production rate in (B) was 10 times higher than that in (A), and the maximum hydrogen production rate in (C) was 1.9 times higher than that in (B). These results demonstrate that microwaves are more efficient at activating solid catalysts (especially metal particles in solid catalysts) than thermal conduction, and millimeter waves are more efficient at activating solid catalysts (especially metal particles in solid catalysts) than microwaves.

[0047] The embodiments and examples disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is indicated by the claims, not by the embodiments and examples described above, and is intended to include the meaning equivalent to the claims and all modifications within the scope. [Explanation of symbols]

[0048] 10 chemical reactor, 11 millimeter wave oscillator, 11m millimeter wave, 12 transmission structure, 12P part of transmission structure, 13 circulator, 15 bidirectional coupler, 16 flexible waveguide, 17 EH tuner, 19 reactor, 19c solid catalyst, 19cc metal particles, 19cs carrier, 20 raw material, 20f fluid, 20s solid, 22 chemical reaction product, 111 oscillation source, 112 amplifier, 112a preamplifier, 112b main amplifier, 152 reflected wave power sensor, 154 traveling wave power sensor, 192 temperature measuring device, 194 detector.

Claims

1. A chemical reaction device comprising: a millimeter wave oscillator that oscillates millimeter waves of 20 GHz or more and 40 GHz or less; a reactor that contains a solid catalyst having millimeter wave absorption properties therein and that accommodates a raw material therein; and a transmission structure that amplifies and transmits the millimeter waves in one direction from the millimeter wave oscillator to the reactor.

2. 2. The chemical reaction device according to claim 1, wherein the reactor is a cavity resonator.

3. 3. The chemical reaction device according to claim 1, wherein the transmission structure includes a circulator connected to the millimeter wave oscillator, a bidirectional coupler connected to the circulator, an EH tuner connected between the bidirectional coupler and the reactor, and a reflected wave power sensor and a forward wave power sensor connected to the bidirectional coupler.

4. 4. The chemical reactor of claim 3, wherein the transmission structure further comprises a flexible waveguide connected between the bidirectional coupler and the EH tuner.

5. The chemical reaction device according to claim 1 or 2, further comprising a temperature measuring device for measuring an internal temperature of the reactor.

6. 3. The chemical reaction device according to claim 1, further comprising a detector for detecting chemical reaction products of said feedstock in said reactor.

7. 3. The chemical reaction device according to claim 1, wherein the solid catalyst comprises a carrier and metal particles supported on the carrier.

8. The chemical reaction device according to claim 7 , wherein the carrier has a lower millimeter wave absorption property than the metal fine particles.

9. The chemical reaction device according to claim 7 , wherein the metal particles have a particle size of 1 nm or more and 100 nm or less.

10. A chemical reaction method using the chemical reaction device according to claim 1 or 2, generating the millimeter wave by the millimeter wave oscillator and supplying the millimeter wave to the solid catalyst in the reactor via the transmission structure; and storing the raw material in the interior of the reactor and contacting the solid catalyst with the raw material.

11. A chemical reaction method using the chemical reaction device according to claim 3, generating the millimeter wave by the millimeter wave oscillator, and supplying the millimeter wave to the solid catalyst in the reactor via the circulator, the bidirectional coupler, and the EH tuner; and storing the raw material in the interior of the reactor and contacting the solid catalyst with the raw material.

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