Heated continuous stirred tank reactor

Abstract

To provide a heating-type continuous agitation tank reactor capable of quickly heating a liquid in a reaction tank by using a microwave, making difficult closing of a reaction path, continuously reacting, and being easily positioned in a chamber with a built-in microwave antenna.SOLUTION: A heating-type continuous agitation tank reactor comprises: a chamber that reflects a microwave therein; an antenna which is disposed in the chamber and through which the microwave is output; and a plurality of reaction tanks having a plurality of bottomed holes provided to a base material. The reaction tanks communicate with each other. The base material having the reaction tanks is provided with a through-hole or a nonthrough-hole for locking the antenna through which the microwave is output. The base material is made of a blank which transmits the microwave.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a heated continuous stirred tank reactor. [Background technology]

[0002] As shown in Patent Document 1 or Patent Document 2 below, there is known an apparatus that irradiates microwaves into a chamber and causes a chemical reaction under heating conditions using the microwaves. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2016 / 208563 publication [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-227322 Summary of the Invention [Problem to be solved by the invention]

[0004] In the apparatus of Patent Document 1, a sealed container is placed in a chamber, a mixture of a mayenite type compound and a carbon component is placed in the container, and the mixture placed in the container is heated by microwaves. This is said to produce an electrically conductive mayenite type compound. This method is a batch type, and therefore has the problem of low efficiency.

[0005] In the apparatus of Patent Document 2, a microwave generator is placed inside a chamber. A reaction solution is flowed through a reaction tube arranged in a spiral around the microwave generator, and the reaction solution is heated by microwaves to continuously produce an organometallic complex. This method is continuous and efficient. However, because the reaction occurs inside the reaction tube, if a solid precipitates as a result of the chemical reaction, the reaction tube may become clogged or scale may form on the reaction tube, resulting in a decrease in efficiency.

[0006] An object of the present invention is to provide a heated continuous stirred tank reactor that can rapidly heat a liquid in a reaction tank by utilizing microwaves, is less likely to cause clogging of the reaction path, allows for continuous reactions, and allows for easy determination of the position of the tank reactor within a chamber that has a built-in microwave antenna. [Means for solving the problem]

[0007] The above-mentioned problems are solved by a heated continuous stirred tank reactor having a chamber that reflects microwaves internally, an antenna that emits microwaves disposed within the chamber, and multiple reaction vessels each consisting of multiple bottomed holes provided in a base material. The multiple reaction vessels are interconnected, and the base material on which the multiple reaction vessels are provided has through-holes or blind holes for attaching a microwave generator. The base material is made of a microwave-transparent material. This heated continuous stirred tank reactor carries out a reaction while circulating a substrate and a catalyst between the multiple reaction vessels. Unlike a microreactor, the reaction does not take place in a minute flow path, so clogging of the reaction path is less likely to occur. This heated continuous stirred tank reactor has a configuration in which a microwave-emitting antenna is attached to through-holes or blind holes in the base material on which the reaction vessels are provided. The position of the tank reactor within the chamber can be uniquely determined. This allows the reactor to be easily placed at a position where the microwave density is high, and the substrate, catalyst, etc. stored in the reactor can be more easily irradiated with microwaves efficiently. These configurations allow the liquid in the reactor to be heated quickly.

[0008] In the above-described heated continuous stirred tank reactor, the chamber is preferably cylindrical, with the antenna located at the center. With this configuration, microwaves irradiated from the antenna are reflected by the inner wall of the chamber. As a result, the microwave density increases around the antenna. Since multiple reaction vessels are located around the antenna, the liquid in the reaction vessels can be efficiently heated.

[0009] The above-mentioned heated continuous stirred tank reactor preferably further includes a cover for closing the openings of the multiple reaction vessels provided in the base. By including the cover, the liquid in the reaction vessels can be prevented from evaporating, allowing the reaction to be carried out under pressurized conditions. A sealant may be provided between the base and the cover to make the reaction vessels liquid-tight.

[0010] In the above-described heated continuous stirred tank reactor, the microwave-emitting antenna and the substrate are preferably configured to be detachable. By making the antenna and the substrate detachable, the substrate can be removed from the chamber containing the antenna, allowing for easy cleaning, inspection, and part replacement of the substrate.

[0011] In the above-mentioned heated continuous stirred tank reactor, it is preferable that microwaves generated by a semiconductor are emitted from the antenna. When a magnetron is used as the microwave source, the microwave wavelengths include an irregular and wide range of wavelengths. On the other hand, when a semiconductor is used as the microwave source, the range of microwave wavelengths is significantly narrower. When generating microwaves of the same output using a semiconductor and a magnetron, the semiconductor requires less applied voltage. Therefore, the use of a semiconductor can reduce power consumption. Furthermore, the use of a semiconductor can heat the liquid in the reaction vessel more uniformly. Furthermore, the heating state can be precisely controlled using techniques such as phase synthesis. [Effects of the Invention]

[0012] According to the present invention, a heated continuous stirred tank reactor can be provided which utilizes microwaves to rapidly heat a liquid in a reaction tank, is less likely to cause blockage of the reaction path, allows for continuous reaction, and allows for easy determination of the position of the tank reactor within a chamber containing a microphone antenna. [Brief explanation of the drawings]

[0013] [Figure 1]FIG. 1 is a perspective view showing one embodiment of a heated continuous stirred tank reactor. [Figure 2] FIG. 2 is a front view of the heated continuous stirred tank reactor of FIG. 1. [Figure 3] FIG. 2 is a plan view of the heated continuous stirred tank reactor of FIG. 1. [Figure 4] FIG. 2 is a bottom view of the heated continuous stirred tank reactor of FIG. 1. [Figure 5] FIG. 4 is a cross-sectional view taken along the line EE in FIG. 3. [Figure 6] FIG. 1 is a perspective view showing only the continuous stirred tank reactor separated from the heated continuous stirred tank reactor. [Figure 7] FIG. 7 is an exploded perspective view of the continuous stirred tank reactor of FIG. 6. [Figure 8] FIG. 7 is a perspective view showing only the substrate separated from the continuous stirred tank reactor of FIG. 6. [Figure 9] FIG. 9 is a plan view of the substrate of FIG. 8. [Figure 10] 10 is a cross-sectional view taken along the dashed line in FIG. 9. [Figure 11] FIG. 1 is a cross-sectional view showing another example of a continuous tank reactor. [Figure 12] FIG. 2 is a diagram showing the distribution of the electric field strength generated by microwaves within the chamber of the heated continuous stirred tank reactor of FIG. 1. [Figure 13] FIG. 1 is a diagram showing the configuration of an apparatus used in a heating experiment in Example 1. [Figure 14] FIG. 1 is a diagram showing the configuration of an apparatus used in a heating experiment in Comparative Example 1. [Figure 15] FIG. 10 is a diagram showing the results of a water heating experiment in an example. DETAILED DESCRIPTION OF THE INVENTION

[0014]

[0033] Hereinafter, embodiments of the heated continuous stirred tank reactor of the present invention will be described. Each of the embodiments shown below is merely a limited example of the heated continuous stirred tank reactor of the present invention, and the technical scope of the present invention is not limited to the exemplified embodiments.

[0015] 1 to 10 show one embodiment of a heated continuous stirred tank reactor (hereinafter simply referred to as a heated reactor).

[0016] As shown in FIGS. 1 to 5, the heating reactor 1 of this embodiment includes a chamber 11 that reflects microwaves therein, an antenna 12 that emits microwaves and is disposed in the chamber 11, and a plurality of reaction vessels 157 each consisting of a plurality of bottomed holes provided in a base material 151.

[0017] 5, a base material 151 provided with a plurality of reaction vessels 157 is provided with through-holes 159 for receiving antennas 12 that emit microwaves. As will be described later, base material 151 is made of a material that transmits microwaves emitted from antennas 12.

[0018] In the heated reactor 1, the chamber 11 is made of aluminum and reflects most of the microwaves emitted from the antenna 12. Aluminum is lightweight and easy to process, making it suitable for use as a material for forming the chamber. The chamber may be made of a material that reflects most of the microwaves irradiated onto the inner wall of the chamber. Examples of such materials that can be used include metals such as stainless steel and copper.

[0019] The chamber 11 has a cylindrical tubular portion 111 and flange portions 112 disposed at the upper and lower ends of the tubular portion. A plate-shaped lid body 13 is fixed to the upper flange portion 112 by screwing. A plate-shaped lid body 14 is also fixed to the lower flange portion 112 by screwing. The lid bodies 13, 14 are made of circular plate-shaped members in a plan view.

[0020] Upper lid 13 is provided with a cylinder 169 serving as an inlet and connected to a through-hole provided in lid 13, and a cylinder 170 serving as a discharge port and connected to a through-hole provided in lid 13. For example, as shown in Figure 13, a flexible liquid supply pipe 166 or liquid drain pipe 167 is inserted into the inlet or discharge port, and liquid supply pipe 166 or liquid drain pipe 167 is connected to liquid supply connector 164 or liquid drain connector 165 of continuous stirred tank reactor 15.

[0021] As shown in Fig. 5, an antenna 12 is disposed at the center of the cylindrical chamber. The lower end of the antenna 12 is fixed to the lower lid 14 by screws. The upper end of the antenna is connected to a connector 168 fixed to a through-hole provided in the upper lid 13. The connector 168 is connected to a microwave generator (not shown).

[0022] The microwave generating unit may use a magnetron as the microwave source, or a semiconductor as the microwave source. When a magnetron is used as the microwave source, the microwave wavelengths will be irregular and will include a wide range of wavelengths. On the other hand, when a semiconductor is used as the microwave source, the range of microwave wavelengths will be significantly narrower. When generating microwaves of the same output using a semiconductor and a magnetron, a semiconductor requires less applied voltage. Therefore, using a semiconductor can reduce power consumption. Furthermore, using a semiconductor can heat the liquid in the reaction vessel more uniformly. Furthermore, techniques such as phase synthesis can be used to precisely control the heating state of the liquid. For this reason, it is preferable to use a semiconductor as the microwave source.

[0023] The bottom of the cylindrical chamber preferably has a flat portion on which the chamber 11 can be placed on a magnetic stirrer 4, as shown in Figure 13. With this configuration, magnetic rotors are placed in the reaction vessel of the continuous stirred tank reactor 15, and the liquid in the reaction vessel can be stirred by rotating the multiple rotors with the magnetic stirrer 4 placed below the continuous stirred tank reactor 15.

[0024] 5, continuous stirred tank reactor 15 is placed within chamber 11. Continuous stirred tank reactor 15 has a base 151 on which multiple reaction vessels 157 are provided, a lid 152 that closes the openings of the multiple reaction vessels provided in base 151, a retaining member 153 for a sealant 155 that is placed between base 151 and lid 152, two strips of sealant 155 that are placed on the inside and outside and fit into grooves provided in retaining member 153, and a bottom member 154 that is placed below base 151.

[0025] A through hole 159 that communicates in the vertical direction is formed in the bottom member 154, the base material 151, the holding member 153, and the lid 152. The through hole 159 is provided in the center of the bottom member 154, etc. A cylindrical sleeve 156 is inserted into the through hole 159, and the antenna 12 is inserted into the sleeve 156. The cylindrical sleeve 156 is rod-shaped, and has a head at its upper end that protrudes in a direction intersecting the axial direction of the sleeve, and a screw groove at its lower end that screws into a screw hole provided on the inner circumferential surface of the through hole in the bottom member 154.

[0026] The bottom member 154 is a plate-like member having the same shape as the base material 151 in a plan view. The bottom member may be any member capable of fixing the sleeve, and its shape is not particularly limited. The lid 152 and the holding member 153 are also members having the same shape as the base material 151 in a plan view. The lid may be any member capable of closing the opening of the reaction vessel, and its shape is not particularly limited. The holding member may be any member capable of holding the sealing material, and its shape is not particularly limited.

[0027] Continuous stirred tank reactor 15 is fixed to chamber 11, for example, as follows. First, with upper lid 13 of chamber 11 removed, antenna 12 is fixed to lower lid 14. Next, antenna 12 is passed through the through-holes of bottom member 154, base 151, holding member 153, and lid 152, using antenna 12 as an axis. Sleeve 156 is passed through each of the through-holes, and sleeve 156 is rotated until the head of sleeve 156 contacts lid 152, and sleeve 156 is screwed onto bottom member 154. Upper lid 13 is attached and fixed to chamber 11. If cylindrical bodies 169 and 170 and connector 168 are attached to lid 13 in advance, they will be fixed to cylindrical portion 111 of chamber 11 together with lid 13.

[0028] As shown in FIG. 7 , the bottom member 154, the base material 151, the holding member 153, and the lid 152 have a plurality of through holes. A plurality of screws 158 are inserted into the through holes. The plurality of screws 158 are threaded into thread grooves cut into the inner circumferential surface of the through holes in the bottom member 154. The screws 158 and the threaded portions of the sleeve 156 are threaded into the bottom member 154, thereby firmly fastening the bottom member 154, the base material 151, the holding member 153, and the lid 152. The bottom member 154 and the like are fastened together with two sealants 155 interposed between the holding member 153 and the base material 151. The outer sealant is disposed outside the plurality of reaction vessels 157. The inner sealant is disposed inside the plurality of reaction vessels 157 so as to contact the sleeve 156. The sealing material 155 arranged in this manner makes the reaction vessel 157 liquid-tight, preventing the liquid inside the reaction vessel from evaporating when heated. The sealing material 155 and the like also make it possible to heat the liquid inside the reaction vessel under pressure.

[0029] In the heating reactor 1 of this embodiment, the bottom member, the base member, the holding member, and the lid are made of polyetherketone (PEEK), a material that has high microwave transmittance, excellent corrosion resistance, and excellent strength. The material constituting the above members is not limited to polyetherketone, and may be any material that has high microwave transmittance. Examples of such materials include acrylic resin, polycarbonate, polypropylene, Teflon (registered trademark), ceramics, and glass.

[0030] As shown in Figures 8 to 10, the continuous stirred tank reactor 15 has a total of four reaction vessels 157. Specifically, it has reaction vessel A at the beginning and reaction vessel D at the end. Reaction vessel B is connected to reaction vessel A and reaction vessel C via a communication hole 160. Reaction vessel C is connected to reaction vessel B and reaction vessel D via a communication hole 160. The communication hole 160 is provided with a partition 161 that protrudes upward from the bottom. The depth of the reaction vessels is shallower upstream and deeper downstream. The protruding height of each partition 161 is the same. With this configuration, as shown by the dashed line in Figure 10, the liquid level is higher in the upstream reaction vessel 157 and lower in the downstream reaction vessel 157. This prevents the downstream reaction liquid from flowing back upstream.

[0031] 8 to 10, a portion of the communication hole 160 reaches the upper end of the base material 15 and forms an opening. This opening is an opening for maintenance. For example, a brush can be inserted through the opening to clean the communication hole.

[0032] As shown in FIG. 7, the lid 152 and the retaining member 153 of the sealing material 155 are provided with through-holes 162, 163 for liquid supply or liquid drainage. The through-hole 162 for liquid supply communicates with the initial reaction vessel A. The through-hole 163 for liquid drainage communicates with the final reaction vessel D. The initial reaction vessel A is connected to multiple through-holes 162 for liquid supply, allowing multiple substances such as reaction substrates to be supplied to the initial reaction vessel A. As shown in FIG. 6, connectors 164, 165 for connecting a liquid supply pipe 166 or a liquid drainage pipe 167 shown in FIG. 13 are connected to the through-holes 162, 163 of the lid 152. The connector 164 communicates with the through-hole 162 for liquid supply. The connector 165 communicates with the through-hole 163 for liquid drainage.

[0033] The configuration of the heated reactor is not limited to the above example. For example, a heated reactor 1b having a continuous stirred tank reactor as shown in FIG. 11 may be used. The continuous stirred tank reactor 15b shown in FIG. 11 includes a base 151b on which multiple reaction vessels 157b are provided, a lid 152b that closes the openings of the multiple reaction vessels 157b provided in the base 151b, and a sealant 155b disposed between the base 151b and the lid 152. Unlike the above example, the continuous stirred tank reactor 15b does not include a sleeve through which the antenna 12 is inserted or a bottom member disposed below the base. The reaction vessels 157b are connected to each other via the communication holes and partitions shown in FIG. 10.

[0034] In continuous stirred tank reactor 15b, chamber 11 and continuous stirred tank reactor 15b are connected by inserting an antenna into a through-hole provided to communicate lid 152b, sealant 155b, and base 151b. Antenna 12 and base 151b are not fixed by screws or the like. This allows continuous stirred tank reactor 15b to be more easily attached to and detached from the chamber. Base 151b, sealant 155b, and lid 152b are fastened together by a plurality of screws 158b. Thread grooves corresponding to screws 158b are provided on the inner circumferential surface of holes provided in base 151b.

[0035] The seal material 155b is a silicone rubber sheet coated with a fluororesin (Teflon (registered trademark)) for the purpose of providing corrosion resistance. The seal material is not limited to this example, and any material having elasticity may be used.

[0036] When using the above-described heated reactor, the heated reactor 1 or 1b is placed on a magnetic stirrer, as shown in FIG. 13. A magnetic stir bar is placed inside each reaction vessel 157 or 157b. A liquid containing one or more substances and / or catalysts is supplied to the starting reaction vessel 157 or 157b using a pump such as a micropump or syringe pump. As shown in FIG. 10, when the liquid level supplied to the starting reaction vessel A via the liquid supply pipe 166 exceeds the height of the partition 161, the liquid overflows and is supplied to reaction vessel B. The reaction liquid is then similarly supplied to reaction vessel C and the terminal reaction vessel D. In each reaction vessel, the liquid is stirred by the stir bar driven by the magnetic stirrer, the substance or catalyst is mixed, and the desired chemical reaction proceeds continuously. The liquid in the terminal reaction vessel D is suctioned via the drain pipe 167 and the pump, and the desired reactant is removed from the heated reactor 1 or 1b.

[0037] In the above-mentioned heated reactors 1 and 1b, the reaction vessels are connected by communication holes with a larger volume than the micropaths of the microreactor, which makes the communication holes less susceptible to clogging by deposits or scales generated as a result of the chemical reaction.

[0038] In the above-described heated reactors 1 and 1b, when the continuous stirred tank reactor is installed in the chamber, an antenna is attached to the substrate. In this configuration, the position of the substrate is uniquely determined by the antenna. This allows the reactor to be placed in a position in the chamber where the microwave-generated electric field is strongest. Microwaves are emitted from the antenna when the antenna is attached to the substrate. As shown in Figure 12, the microwave-generated electric field strength is strong around the antenna. By placing the substrate so that the antenna is attached to the substrate, the reactor is placed in an area where the electric field strength is strong, thereby enabling efficient heating of the liquid in the reactor. In Figure 12, the electric field strength is strongest in the nearly white area adjacent to the antenna, followed by the light-colored, approximately circular area outside that area. The electric field strength is weakest in the dark-colored area outside the circle.

[0039] The configuration of the sealing material may be any as long as it can keep the reaction vessel liquid-tight. The sealing material is not limited to the above examples, and its shape, material, and placement position can be changed.

[0040] In the above example, the chamber 11 includes the flange 112 and the cylindrical bodies 169 and 170. The flange 112 or the cylindrical bodies 169 and 170 are not essential and may be omitted. Also, in the above example, the portion where the base material and the antenna are hooked is a through hole. The hooking portion may also be a recessed hole that does not penetrate the base material.

[0041] In the above example, the continuous stirred tank reactor is provided with a lid, a bottom member, a sealant retaining member, or a sealant. The lid, the bottom member, the sealant retaining member, or the sealant is not essential and may be omitted. In addition, in the above example, two through-holes for liquid supply are connected to the first reaction tank, and one through-hole for liquid drainage is connected to the last reaction tank. The number of through-holes for liquid injection or liquid drainage is not particularly limited. The through-hole for liquid injection does not necessarily have to be provided in the first storage tank, and may be provided so as to communicate with the second or subsequent storage tanks, for example.

[0042] The present invention will be specifically described below with reference to examples.

[0043] [Example 1] As shown in Figure 13, a heated reactor 1 having a configuration similar to that shown in Figure 5 was placed on a magnetic stirrer 4, and a magnetic rotor was placed in each reaction vessel. Room-temperature water stored in a flask 172 was supplied to the first reaction vessel at a flow rate of 20 ml / min via a pump 171 and a liquid supply pipe 166. A microwave generator using a GaN semiconductor as the microwave source emitted 2.5 GHz microwaves at an output of 200 W from an antenna 12. Liquid was withdrawn from the last reaction vessel 157 at a flow rate of 20 ml / min via a pump 171 and a liquid drain pipe 167. As shown in Figure 13, an alcohol thermometer was inserted into the last reaction vessel 157 to measure the liquid temperature over time. The temperature measurement results are shown in the graph in Figure 15.

[0044] [Example 2] Except for changing the flow rate of water supply to 10 ml / min, the water was heated in the same manner as in Example 1. The change in liquid temperature in the reaction vessel over time is shown in FIG.

[0045] [Comparative Example 1] As shown in FIG. 14, the substrate 151 constituting the continuous stirred tank reactor shown in FIG. 5 was placed on an electrically heated magnetic stirrer 4, and a magnetic rotor was placed in each reactor. Room temperature water stored in a flask 172 was supplied to the first reactor at a flow rate of 10 ml / min via a pump 171 and a liquid supply pipe 166. The substrate was heated from its bottom using the heating wire of the magnetic stirrer 4 at an output of 200 W. Liquid was withdrawn from the last reactor 157 at a flow rate of 10 ml / min via a pump 171 and a liquid drain pipe 167. As shown in FIG. 14, an alcohol thermometer 6 was inserted into the last reactor 157 to measure the liquid temperature over time. The temperature measurement results are shown in the graph in FIG. 15.

[0046] Comparative Example 2 Except for changing the flow rate of water supply to 20 ml / min, the water was heated in the same manner as in Comparative Example 1. The change in liquid temperature over time is shown in FIG.

[0047] As is clear from the graph in FIG. 15, the heated reactors of Examples 1 and 2 were able to heat the liquid temperature in the reaction tank to a predetermined temperature in a shorter time than the heating methods of Comparative Examples 1 and 2. [Explanation of symbols]

[0048] 11 Chambers 12 Antenna 157 Reactor 159 Through Hole 151 Base material 152 Lid 153 Sealing material 4 magnetic stirrers

Claims

1. a chamber that reflects microwaves therein; an antenna that emits microwaves and is disposed within the chamber; a heated continuous-tank reactor having a plurality of reaction vessels each consisting of a plurality of bottomed holes provided in a base material, The reaction vessels are connected to each other through communication holes, the substrate on which the plurality of reaction vessels are provided has a through hole or a blind hole for attaching an antenna for emitting microwaves; The base material is made of a material that is transparent to microwaves. The antenna is hung in a through hole or a non-through hole of the base material; In the plurality of connected reaction tanks, liquid flows through the communication hole from the reaction tank on the starting side to the reaction tank on the terminal side, and microwaves emitted from the antenna and microwaves reflected by the chamber are transmitted through the base material and act on the liquid in the reaction tanks to heat the liquid, thereby continuously carrying out a predetermined reaction in the plurality of reaction tanks.

2. 2. The heated continuous-tank reactor according to claim 1, wherein the chamber is cylindrical and the antenna is disposed at the center of the chamber.

3. 3. The heated continuous-tank reactor according to claim 1, further comprising lids for closing openings of the plurality of reaction vessels provided on the base.

4. 4. The heated continuous-tank reactor according to claim 3, further comprising a sealant between the base and the lid for making the reactor liquid-tight.

5. A continuous tank reactor as described in any one of claims 1 to 4, wherein the liquid in the reaction tank is stirred by a stirring bar driven by a magnetic stirrer.

6. 6. The heated continuous-tank reactor according to claim 1, wherein the antenna for emitting microwaves and the base material are detachably attached to each other.

7. 7. The heated continuous-tank reactor according to claim 1, wherein microwaves generated by a semiconductor are emitted from the antenna.

Images