JP4348451B2 - Nanoparticle production method and apparatus therefor - Google Patents

Description

  The present invention relates to a nanoparticle manufacturing method and a nanoparticle manufacturing apparatus for manufacturing nanometer-order fine particles. More specifically, the present invention relates to a microstructure for a chemical reaction, and relates to a nanoparticle manufacturing method and a nanoparticle manufacturing apparatus for manufacturing nanometer-order fine particles using a microreactor that performs a chemical reaction in a minute space.

  In recent years, research aimed at improving the efficiency of chemical reactions using microreactors and creating new compounds has attracted attention. This microreactor causes a chemical reaction in a narrow channel having a diameter on the order of submicrometer to millimeter. Since the heat capacity of the liquid in the flow path is reduced, heat exchange from other parts constituting the microreactor to the flow path can be performed quickly, and temperature control of the chemical reaction in the flow path can be facilitated.

  In addition, the microreactor can control the chemical reaction between the solution layers flowing in the flow path, bringing about innovative changes in chemical synthesis, creation of new compounds, analysis and analysis of various samples, etc. It is highly expected as a thing. Patent Document 1 discloses a method for producing nanoparticles using a fine channel having an inner diameter of 1 μm to 1 mm. Specifically, the particle-forming precursor-containing solution is rapidly heated to the reaction start temperature while being continuously supplied into the fine channel, and after the reaction is performed, the solution is rapidly cooled to control the heating temperature and the reaction time. It is something to do.

  Patent Document 2 discloses a chaotic mixer. The chaotic mixer performs mixing by three-dimensionally folding a laminar flow of a plurality of solutions. Patent Document 3 discloses a microreactor in which a sample solution and a reagent solution are injected into a microreaction main body, and stirred and mixed with a nanomaterial stirrer to perform a reaction. In addition, a heating part and a cooling part are provided in the micro reaction main body part, and the reaction between the sample solution and the reagent solution is performed while controlling the temperature.

The ceramic microreactor shown in Non-Patent Document 1 generates nanoparticles with two types of reaction solutions flowing in a laminar flow. In the zigzag channel of Non-Patent Document 2, two types of solutions are injected to generate nanoparticles.
JP 2003-225900 A JP 2004-283791 A JP 2004-321063 A H. Wang et.al., Chem. Comm., Pp. 1462-1463 (2002) Paul JAKenis et.al., Science, vol285, p83-85 (1999)

  Thus, one of the major features of the microreactor is that the flow in the tube is a laminar flow, so back mixing does not occur and the residence time distribution of the reaction solution can be kept narrow. However, even if the inside of the tube is laminar, the flow velocity distribution can be made in the direction perpendicular to the flow due to friction with the wall, so there is a problem that the particle size distribution of the generated nanoparticles is widened due to slight variations in the heating time. There is.

  In addition, a microreactor is placed in an oil bath or the like, and a reaction is performed to generate nanoparticles (Patent Document 1). When nanoparticles are produced in this way, the microreactor must be replaced for each reaction. Further, when the reaction is to be performed at a plurality of temperatures, the microreactor must be transferred to an oil bath or the like controlled at different temperatures, and automation thereof is desired.

  In the method for producing nanoparticles described in Patent Document 1, when synthesizing nanoparticles, two liquids are mixed in advance, or a sample solution and a reagent solution are forcibly stirred with a nanomaterial stirrer, Thereafter, heating is performed to obtain a product. In this case, since the inner wall of the tube and the mixed solution are in contact with each other, an interaction between the product generated by the contact and the wall surface of the container often occurs.

  The chaotic mixer described in Patent Document 2 basically performs a three-dimensional folding of laminar flow, but because of its complicated structure, it causes partial turbulence especially when the flow velocity is high. There is a problem that it is easy. In the nanoparticle production method described in Patent Document 3, when a nanoparticle is synthesized, the sample solution and the reagent solution are forcibly stirred by a nanomaterial stirrer. The sample solution and the reagent solution are forcibly stirred by the nanomaterial stirrer to cause turbulent flow to control the chemical reaction.

The present invention has been made based on the technical background as described above, and achieves the following objects.
An object of the present invention is to provide a nanoparticle production method and a nanoparticle production apparatus in which a fine reactor for producing nanoparticles is produced while relatively moving in a temperature-controlled zone.

  Another object of the present invention is to provide nanoparticles having a uniform particle size distribution while a fine reactor containing or attaching a reaction solution for producing nanoparticles is relatively moved in a temperature-controlled zone. Provided are a nanoparticle manufacturing method and a nanoparticle manufacturing apparatus.

  Another object of the present invention is to produce nanoparticles having a small variation in particle size by controlling the reaction time easily while the microreactor moves relatively in a temperature-controlled zone. A production method and a nanoparticle production apparatus are provided.

  Still another object of the present invention is to provide a plurality of raw materials while the fine reactor moves relatively in the temperature-controlled zone, and the interaction between the tube wall and the intermediate product and the tube wall and the product is interrupted. Provided are a nanoparticle production method and a nanoparticle production apparatus that allow a solution to be mixed and reacted.

In order to achieve the above object, the present invention employs the following means.
Nanoparticles production method of the present invention 1, the reactor characteristic length 1 m to 1 mm, supplying a raw material solution for making nanoparticles, the solution was the solution still after being introduced into the reactor In the state, the reaction is performed while the reactor and the zone are relatively moved by the conveying means so that the reactor moves in the temperature-controlled zone by the temperature control means. .

  The nanoparticle production method of the present invention 2 is carried out in the nanoparticle production method of the present invention 1, wherein the zone is heated in a temperature controlled by heating up to the reaction start temperature, and the heating zone. The reaction zone while the reactor and the heating zone are moved relative to each other by the transport means so that the reactor is transported in the heating zone. Then, the reactor is rapidly cooled while relatively moving the reactor and the cooling zone by the transfer means.

  The nanoparticle production method of the present invention 3 is the nanoparticle production method of the present invention 1 or 2, wherein the reactor comprises a tube having an inner diameter of the representative length, a line having a diameter of the representative length, One thin space selected from a thin film having a thickness of a representative length and pores having the representative length is characterized in that

  The nanoparticle production method of the present invention 4 is the nanoparticle production method according to 1 invention selected from the present invention 1 to 3, wherein the solution is supplied to the reactor to form two or more layers of the solution. And the reaction is performed by a diffusion reaction between the layers.

  The nanoparticle production method of the present invention 5 is the nanoparticle production method of the first or second aspect of the present invention, wherein the reactor comprises a fine channel having an inner diameter of the representative length and is connected to the fine channel. The solution is supplied in a laminar flow from the plurality of sample supply channels to the fine channel having a cross-sectional area smaller than the sum of the cross-sectional areas of the plurality of sample supply channels, and the laminar flow of the solution is maintained. The reaction product after the reaction is discharged from a sample discharge flow channel connected to the fine flow channel.

Nanoparticles manufacturing apparatus of the present invention 6, the reactor characteristic length 1 m to 1 mm, and the solution supply means for supplying a raw material solution for producing nanoparticles, in a state where the supply is stopped, the Relatively reacting the reactor for causing the reaction of the solution, temperature control means for controlling the temperature by heating or cooling the reactor, the zone temperature-controlled by the temperature control means, and the reactor It is characterized by comprising a conveying means for moving in an automatic manner.

A nanoparticle production apparatus according to a seventh aspect of the invention is the nanoparticle production apparatus according to the sixth aspect, wherein the zone includes a heating zone for heating the reactor up to the start temperature of the reaction, and the heating zone. And a cooling zone for quenching the reaction
The conveying means causes the reactor to alternate between the heating zone and the cooling zone so that the reaction is performed while moving in the heating zone, and then rapidly cooled while relatively moving in the cooling zone. The reaction is performed while moving.

  The nanoparticle production apparatus of the present invention 8 is the nanoparticle production apparatus of the present invention 6 or 7, wherein the reactor is a tube having an inner diameter of the representative length, a line having a diameter of the representative length, An apparatus for producing nanoparticles, comprising a thin film having a thickness of a representative length and one fine space selected from the pores having the representative length.

  The nanoparticle production apparatus of the present invention 9 is the nanoparticle production apparatus of the present invention 6 or 7, wherein the solution is supplied from the solution supply means to the reactor so as to form two or more layers, The reaction is performed by a diffusion reaction between the layers.

Nanoparticles manufacturing apparatus of the present invention 10 is the nanoparticle manufacturing apparatus according to the present invention 6 or 7, wherein the reactor consists of the micro-channel of the inner diameter of the representative length, 3 for producing nanoparticles A plurality of sample supply channels for supplying a plurality of types of raw material solutions in a laminar flow, and the fine flow connected to the sample supply channels and having a cross-sectional area smaller than the sum of the cross-sectional areas of the plurality of sample supply channels And a sample discharge flow channel connected to the fine flow channel for discharging the reaction product after the reaction after the reaction is performed in the fine flow channel.

The nanoparticle production apparatus according to the eleventh aspect of the invention is the nanoparticle production apparatus according to the tenth aspect of the invention, wherein the sample supply channel comprises a capillary, and a syringe connector is provided at one end of the capillary that is not connected to the fine channel. be connected, during the transport, the said solution from the syringe connector is supplied to the capillary, the is arranged a flow in the microchannel in two dimensions, causing the reaction between the flow adjacent layers It is characterized by that.

  The nanoparticle production apparatus of the present invention is an apparatus for producing nanoparticles by incorporating or attaching a reaction solution and carrying a microreactor for carrying out the reaction by a carrying unit. The nanoparticle production apparatus of the present invention has a temperature control unit for heating the microreactor to the optimum reaction temperature and cooling after the reaction. The nanoparticle production apparatus of the present invention relatively conveys the microreactor and the temperature control unit, and causes the reaction solution to react while passing through the temperature control unit to produce nanoparticles.

  As the microreactor, a reactor having a representative length of 1 μm to 1 mm is used. For example, a fine channel having a diameter with a representative length of 1 μm to 1 mm is used. The reaction solution is supplied to the microreactor and stopped, and the microreactor containing or adhering the reaction solution is conveyed by the conveyance unit to produce nanoparticles. Since the reaction solution in the microreactor does not move relative to the microreactor, the relative moving speed of the microreactor and the reaction solution becomes zero. For this reason, when the relative moving speed is not 0, that is, when the reaction solution flows in the tube, the flow velocity distribution generated in the direction perpendicular to the flow does not occur.

  For this reason, since the residence time distribution of the reaction solution does not occur and a more uniform reaction time distribution is obtained, the particle size distribution of the nanoparticles can be suppressed more uniformly. To convey the microreactor and the temperature control unit relatively is to convey the microreactor while fixing the temperature control unit while the temperature control unit heats a part of the microreactor. In contrast, it shows that the microreactor is fixed and the temperature controller is transported, and that the microreactor and the temperature controller are transported at different speeds.

  In the nanoparticle production apparatus of the present invention, the reaction solution is transported for each microreactor so that the flow rate distribution does not occur due to friction between the tube wall and the reaction solution in the microchannel of the microreactor. Alternatively, the microreactor can be stopped and the temperature control unit can be moved to perform the same reaction. The microreactor is caused to react while supplying a plurality of solutions to the microreactor while circulating around the temperature control unit including a plurality of heating units or cooling units by the transport unit. The transport unit can also have a gripping part for gripping the microreactor.

According to the present invention, the following effects can be obtained.
The present invention makes it possible to produce nanoparticles by relatively moving a minute reactor such as a fine channel and a temperature-controlled zone.
The present invention controls the flow rate distribution of the reaction solution in the fine channel by controlling the supply of the reaction solution to the fine channel to be stopped when the fine channel is heated. It became possible to produce nanoparticles with little variation.

  In the present invention, the nanoparticles are produced while relatively moving the fine channel filled with the reaction solution and the temperature-controlled zone, so that the tube wall and the intermediate product, the tube wall and the product are separated. It has become possible to mix and react multiple reaction solutions while interrupting the interaction.

  Next, Embodiment 1 of the present invention will be described with reference to the accompanying drawings. In FIG. 1, the outline | summary of the nanoparticle manufacturing apparatus 10 of Embodiment 1 of this invention is illustrated. The nanoparticle manufacturing apparatus 10 heats or cools the microreactor 1, a gripping device 11 for gripping or hanging the microreactor 1, a transport path 12 for transporting the gripping device 11 gripping the microreactor 1, and the microreactor 1. For example, the temperature control unit 13 is provided. Further, as will be described later, the gripping instrument 11 moves on the transport path 12 and transfers the microreactor 1 between the temperature control units 13.

  The microreactor 1 contains a reaction solution and performs the reaction to generate nanoparticles. The microreactor 1 includes a fine channel 3 (see FIG. 2) for causing a reaction, a supply unit for supplying a solution to the fine channel 3, and a discharge pipe 4 for taking out the liquid and nanoparticles after the reaction. Is. In this example, the supply unit includes a capillary tube 2, a syringe connector 5, a syringe 6, an air pump 7, and the like. FIG. 2 is a schematic diagram showing the microreactor 1 and the gripping device 11 of the first embodiment. The gripping tool 11 is a gripping tool that grips or fixes the microreactor 1.

  The transport path 12 is for transporting the gripping instrument 11 that grips the microreactor 1. FIG. 1 illustrates only a part of the conveyance path 12, and the conveyance path 12 has an annular closed structure. That is, the conveyance path 12 constitutes a circulation conveyance path that conveys the microreactor 1 and passes through the temperature control unit 13 to return the nanoparticles to their original positions after production. The transport path 12 includes a supply path for supplying the microreactor 1 and a discharge path for discharging the microreactor 1 after generating the nanoparticles (not shown). Since these detailed structures are not the gist of the present invention, the description thereof is omitted. After all, the transport path 12 and the gripping device 11 constitute a transport means of the microreactor 1.

  The transport path 12 includes various transport mechanisms for transporting the gripping tool 11 on the transport path 12 and its driving means. The transport mechanism includes a transport mechanism (not shown) such as a guide rail, a belt or a chain, and a driving means (not shown) such as a motor and a hydraulic device for driving the same, and a transport control device for controlling them. I have. The transport control device has a function of stopping the microreactor 1 at a desired position of the oil bath 15.

  The temperature control unit 13 is for heating or cooling the microreactor 1. The temperature control unit 13 creates an environment having an optimum temperature necessary for a plurality of solutions to be injected into the microreactor 1 to react. The temperature control unit 13 includes a plurality of oil baths 15 and air for heating or cooling the whole or a part of the microreactor 1 as shown in FIG. In addition, if the temperature control of the microreactor 1 and its temperature distribution can be controlled appropriately, it is not limited to the oil bath 15 as in this example. For example, the temperature control unit 13 may be an electromagnetic wave irradiator, a laser irradiator, a hot air blower that blows hot air or cold air, or a cold air blower.

  The oil bath 15 of the temperature control unit 13 in this example is a heating unit, but may be a cooling unit. The cooling means of the temperature control unit 13 can be performed by natural cooling, air cooling, water cooling, oil cooling or the like, and as a device for this purpose, a system is generally selected arbitrarily from cooling devices equipped with a refrigerator. Used by incorporating it into Further, the temperature control unit 13 may be a unit that heats or cools locally by disposing a small heating element, a Peltier element or the like around the fine flow path 3.

  The temperature control unit 13 according to the first embodiment of the present invention includes a plurality of oil baths 15 containing heating oil, a temperature measuring device 16 for measuring the temperature, an oil temperature and a water level in the oil bath 15. The control mechanism 17 etc. which control etc. are comprised. The temperature control unit 13 has a quenching unit for taking out the microreactor 1 put in the oil bath 15 and causing the reaction to take out from the oil bath 15 and quenching. The quenching section may be a cooled heat medium such as oil or water, but may be, for example, an air whose temperature is controlled at room temperature.

[Overall operation]
The microreactor 1 is held by a holding device 11 as shown in FIGS. The gripping device 11 is transported by the transport path 12 while gripping the microreactor 1 and arrives at the temperature control unit 13. The conveyance direction of the gripping instrument 11 conveyed on the conveyance path 12 is a direction indicated by an arrow A (see FIG. 1). The gripping instrument 11 is transferred to a position on the first oil bath 15 in the traveling direction and stopped.

  Then, by driving the gripping device 11, the microreactor 1 is lowered, and all or part of the microreactor 1 is immersed in the oil bath 15 and heated to the optimum reaction temperature. In the microreactor 1 heated to the optimum reaction temperature, the reaction solution built in or attached to the microreactor 1 accelerates the reaction to generate nanoparticles. The lowering and raising of the gripping instrument 11 will be described in detail in the description of the gripping instrument 11 described below (see FIG. 2), and will be omitted here.

  When a predetermined time necessary for the reaction of the solution elapses, the grasping device 11 rises and is conveyed again to the next oil bath 15 through the conveyance path 12 while being rapidly cooled at room temperature. In the same manner as described above, the microreactor 1 is placed in the oil bath 15 and heated. Thus, when all the temperature control necessary for the production | generation of the nanoparticle in the microreactor 1 is completed, the holding | gripping instrument 11 which hold | gripped the microreactor 1 will come out of the temperature control part 13. FIG. The grasping device 11 proceeds to the next step in order to take out the generated nanoparticles.

  The heating rate when heating by being immersed in the oil bath 15 needs to be sufficiently higher than the deposition rate of the particles. Specifically, the heating rate is 0.01 seconds to 1 second, preferably 0.01 seconds or more and 0.3 seconds or less, and all the heated parts of the microreactor 1 are placed in the heating zone. desirable.

[Microreactor 1]
FIG. 2 shows an outline of the structure of the microreactor 1 according to the first embodiment. The microreactor 1 includes a supply unit for rectifying a plurality of solutions and feeding them into the microchannel 3, a microchannel 3 in which the plurality of solutions are mixed in a laminar flow state and a chemical reaction is performed, and reaction generation after the reaction It is a microreactor composed of a discharge pipe 4 and the like for discharging a product and a reaction residual solution. The microreactor 1 mixes a plurality of solutions in the fine flow path 3 in a laminar flow state to cause a chemical reaction, or causes the chemical reaction to flow while directly flowing in the discharge pipe 4 in a laminar flow state. Can do.

  In this example, the supply unit includes a plurality of capillary tubes 2, a syringe connector 5, a syringe 6, an air pump 7, and the like. One end of the capillary tube 2 is connected to the fine channel 3, and the other end is connected to the syringe connector 5. A syringe 6 for supplying a solution is connected to the syringe connector 5. The solution is supplied from the syringe 6 to the capillary tube 2, sent to the microchannel 3, and mixed in a layered state in the microchannel 3 to perform a chemical reaction. The capillary tube 2 of the first embodiment has an inner hole diameter of 1 μm to 1 mm.

  The method for joining the capillary tube 2 and the fine channel 3 is not particularly limited, but an adhesive that does not affect the reaction, a heat-resistant adhesive that can withstand a high-temperature reaction, or the like can be used. The microreactor 1 includes an air pump 7 for adjusting the amount of solution injected. Each air pump 7 is operated to adjust the injection amount of the solution injected into the capillary tube 2, that is, the injection speed per unit time. A plurality of capillary tubes 2 are respectively connected to one end face of the micro flow path 3.

  In the example shown in FIG. 2, three capillary tubes 2 are illustrated. The number of capillary tubes 2 can be changed depending on the type and number of solutions required for the reaction. For example, when all the reaction solutions are mixed and injected into the fine channel 3, a single capillary tube 2 may be used. In addition, when injecting reaction solutions from separate capillary tubes 2, there may be provided as many capillary tubes 2 as the number of reaction solutions.

  One end of the discharge pipe 4 is fixed to the other end of the fine channel 3. The inner diameter of the inner hole of the fine channel 3 is preferably in the range of 1 μm to 1 mm. When the inner diameter is reduced in this way, the ratio of the volume to the surface area of the solution passing through the fine channel 3 is reduced, and the heat applied from the outside by heating can be uniformly transmitted to the whole in a short time. Therefore, there is an advantage that the heating control of the reaction becomes easy. Further, when the inner diameter of the fine flow path 3 is smaller than 1 μm, it becomes difficult to handle as a manufacturing apparatus, and the pressure loss in the apparatus increases during operation, and the production efficiency decreases.

  The layer thickness of the raw material solution can be controlled by selecting a thin tube through which the raw material solution flows, but can be changed depending on the flow rate ratio. When the flow rate from a certain thin tube is made slower than the flow rate of other thin tubes, the film thickness decreases, and conversely, the flow rate increases to increase the thickness. The reaction product and the reaction residual solution taken out into the atmosphere through the discharge pipe 4 are collected in a collector (not shown) or the like. When the fine flow path 3 passes through a heating zone constituted by an oil bath or the like, the fine flow path 3 is rapidly heated to the reaction start temperature and the reaction is performed.

  Separate solutions are respectively supplied from the capillary tube 2, mixed in the microchannel 3, pass through while maintaining a laminar flow, cause a reaction, and are led to the discharge tube 4. At this time, the flow of each solution is a laminar flow in the microchannel 3. Since each solution flow is a laminar flow, a chemical reaction basically takes place only between adjacent laminar flows. As materials for the capillary tube 2 and the fine channel 3, glass, metal, alloy, plastic such as polyolefin, polyvinyl chloride, polyamide, polyester, fluororesin, polyimide resin, or the like can be used.

  In addition, the fine flow path 3 has a tube-like shape having a circular inner hole in cross section, or a metal oxide such as silica, alumina or titania on a heat-resistant substrate such as metal or alloy. Alternatively, a heat-resistant plastic layer such as a fluorine resin or a polyimide resin may be provided, and a groove having a width of 1 μm to 1 mm may be engraved by laser processing, corrosion, or the like.

  In the above-described embodiment, heating or cooling means is arranged in the temperature control unit 13, but the moving microreactor 1 is used for heating the reaction solution to an optimum reaction temperature and for cooling after the reaction. The cooling means can also be provided. As a heating means, a heating medium liquid such as oil, a heat plate, an electric furnace, an infrared ray, a heater, a high frequency heater, a means commonly used for normal heating such as heating by laser light irradiation, etc. It can also be selected and used as appropriate. These heating methods may be either a method of moving the microreactor 1 or a method of moving these heating means relative to the river.

[Temperature control unit 13]
FIG. 1 illustrates an outline of an example of the temperature control unit 13. The temperature control unit 13 includes an oil bath 15 and oil that is contained in the oil bath 15 and heated to the optimum reaction temperature. The oil bath 15 includes a heating mechanism (not shown) for heating the oil to the optimum reaction temperature, a temperature measuring device 16 for measuring the temperature of the oil, and a control mechanism for controlling the operation of the heating mechanism. 17 is provided.

  The control mechanism 17 has a function of measuring whether or not sufficient oil is contained in the oil bath 15 by a liquid measurement mechanism (not shown), and supplying the oil bath 15 by an oil supply mechanism (not shown). The control mechanism 17 heats the oil by controlling the heating mechanism so that the reaction temperature reaches the optimum temperature while measuring the temperature of the oil by the temperature measuring device 16. The temperature control unit 13 has a quenching unit for taking out the microreactor 1 that has been put into the oil bath 15 and performing the reaction from the oil bath 15 into the atmosphere and quenching. The quenching portion may be, for example, air whose temperature is controlled as a heat medium.

[Gripping instrument 11]
FIG. 2 illustrates an outline of the grasping instrument 11. The gripping instrument 11 includes two support shafts 23, wheels provided at the end thereof, a vertical transfer mechanism 20 including a cylinder mechanism, a piston rod 21, a gripping portion 22 fixed to the piston rod 21, and the like. . The wheels are for rolling on the transport path 12 and transporting the entire gripping instrument 11. A drive mechanism for transporting the gripping instrument 11 on the transport path 12 is a drive mechanism such as a chain or a belt (not shown). This drive mechanism can be stopped at a desired position. The grip portion 22 is for gripping and fixing the microreactor 1. The gripping part 22 includes an attachment / detachment mechanism (not shown) for detachably holding the microreactor 1. However, the gripping part 22 may be exchangeable with the microreactor 1 attached. The vertical transfer mechanism 20 is connected to the grip portion 22 by the piston rod 21 and drives the grip portion 22 up and down.

  The microreactor 1 includes an air pump 7 for adjusting the amount of solution injected. The air pump 7 may have any structure as long as the amount of solution injected into the microreactor 1 can be adjusted. This air pump 7 is a known technique, and detailed description thereof is omitted. When the gripping device 11 comes on the oil bath 15, the vertical transfer mechanism 20 operates to lower the grip portion 22 that grips the microreactor 1 and put it into the oil bath 15.

  After a predetermined time, the vertical transfer mechanism 20 operates again, and the grip portion 22 that grips the microreactor 1 is raised and taken out from the oil bath 15. When the gripping portion 22 extends downward and the microreactor 1 is inserted into the oil in the oil bath 15, it is heated rapidly. When the gripping portion 22 is raised upward and the microreactor 1 comes out of the oil bath 15 into the atmosphere, the microreactor 1 is rapidly cooled. Thus, the microreactor 1 containing the reaction solution is rapidly heated and rapidly cooled to control the reaction temperature.

  By controlling the transfer speed of the gripping device 11 and the speed at which the gripping portion 22 descends or rises, the reaction temperature can be controlled arbitrarily. Since the microreactor 1 containing the reaction solution moves in the temperature control unit 13, turbulent flow of the reaction solution can be suppressed as in the past, and the particle size of the generated nanoparticles can be made uniform. The quality of the produced nanoparticles can be improved.

  The microreactor 1 can operate in the following manner. The solution is injected and stopped until the solution is filled into the fine flow path 3 by the air pump 7. Nanoparticles are produced by reacting the solution in the fine flow path 3 into which the solution has been injected by the transport path 12 and the vertical transfer mechanism 20 while alternately moving the oil bath 15 and the atmosphere.

  When the microchannel 3 comes out of the temperature control unit 13, a new solution is injected into the microchannel 3 by the air pump 7 and the solution after the reaction is discharged. The fine flow path 3 newly filled with the solution is reacted with the solution while the oil path 15 and the atmosphere are alternately moved by the transport path 12 and the vertical transfer mechanism 20 to generate nanoparticles. In this case, the conveyance path 12 is an annular mechanism for circulating the oil bath 15 as described above.

[Embodiment 2]
Next, a second embodiment of the present invention will be described. In FIG. 3, the outline | summary of the nanoparticle manufacturing apparatus 30 of this invention is illustrated. The nanoparticle manufacturing apparatus 30 includes a reactor 31, a transport unit, and a temperature control unit. The reactor 31 is a long and thin line. The nanoparticle production apparatus 30 further includes a supply mechanism (not shown) for supplying a reaction solution to the reactor 31, and a discharge mechanism (see FIG. 2) for discharging the reaction residual liquid containing the produced nanoparticles after the reaction. (Not shown).

  The transport unit includes a gripping device 32 for gripping the reactor 31 and continuously flowing the reactor 31, and a plurality of pulleys 33 for transporting the reactor 31. The conveyance unit preferably includes a control mechanism that stops the reactor 31 for a certain period of time. The transport unit can also include an instrument (not shown) for gripping and fixing the supply mechanism and the discharge mechanism. The temperature control unit includes a heating unit (not shown) for heating the reactor 31. The reactor 31 is continuously transported from the gripping device 32 in the direction indicated by the arrow B, and is transported via a plurality of pulleys 33. The middle of this flow passes through the heating zone 34 heated by the heating unit.

  The temperature control unit has a cooling unit (not shown) for cooling the reactor 31 heated by the heating unit. The temperature control unit can design and control the heating / cooling profile of the reaction solution by providing an appropriate temperature distribution in the environment in which the reactor 31 is transported. The cooling unit may be, for example, air that is temperature-controlled at room temperature. The temperature control unit measures a temperature measuring device (not shown) for measuring the temperature of the heating unit and the cooling unit, the heating time of the heating unit, the cooling time of the cooling unit, etc., and the time for performing the control A measuring instrument (not shown) can be provided.

  A conveyance part conveys the reactor 31 and a temperature control part relatively. That is, the transport unit can transport the reactor 31 and pass through the heating zone 34 with the temperature control unit stopped. Further, in a state where the reactor 31 is stopped, the transport unit can transport the temperature control unit so that the reactor 31 passes through the heating zone 34. Further, the transport unit can transport the temperature control unit and the reactor 31 at different transport speeds so that the reactor 31 passes through the heating zone 34.

  The time measuring device can control the heating time and the cooling time in conjunction with the transport unit. For example, the heating unit heats a part of the reactor 31 for a predetermined time, causes the solution to react, and stops the heating. A portion of the reactor 31 that is disposed in the heating zone 34 is heated to react the solution. When heating of the heating unit is stopped, the reactor 31 is cooled by the atmosphere. Thereafter, the reactor 31 is fed by the transport unit, and a new part of the reactor 31 is disposed in the heating zone 34. In this manner, the reaction is performed on the reaction solution while the reactors 31 are sequentially fed.

  As the supply mechanism, the same supply unit as that shown in Embodiment Mode 1 can be used. The reactor 31 is similar to the fine channel 3 shown in the first embodiment, and uses a long thin tube. Furthermore, it is preferable that a conveyance part has the conveyance path 35 for conveying the supply mechanism, the reactor 31, the holding | gripping instrument 32, and the pulley 33 all. Such a conveyance path 35 is useful when the reactor 31 and the supply mechanism are replaced. Further, in the case of an oil bath or the like, the heating unit of the temperature control unit is useful when controlling the reactor 31 and the pulley 33 by putting them in and out of the oil bath or the like by the conveyance path 35.

  The reaction solution is preferably discharged in a state where the flow in the tube is a laminar flow. If the flow at the time of discharge is laminar, when it is discharged, it will be discharged sequentially from the vicinity of the discharge port of the discharge mechanism, so when there is a part where the heating state is uneven, such as at the beginning or end of heating Can be separated upon discharge. As a reactor, the following can be used in addition to the above-mentioned capillary tube. For example, as the reactor, it is possible to use a fine wire made of a material not involved in the reaction, a porous body made of a material not involved in the reaction, or the like. Further, as the reactor, it is possible to use a material that does not participate in the reaction and that is dissolved in a material such as a polymer that maintains a solid state even when the reaction solution is dissolved.

  When a thin wire is used as the reactor, the reaction solution is thinly attached to the surface of the thin wire, for example, with a thickness of up to 1 mm, and can be heated by an appropriate method such as an infrared image furnace. After the reaction, it is possible to obtain a solution containing the generated fine particles by washing out an appropriate portion of the thin wire. Moreover, when using a porous body, a polymer | macromolecule, etc. as a reactor, after impregnating or dissolving a reaction solution in the hole, it is possible to heat by appropriate methods, such as an infrared image furnace. In the case of a porous body, after the reaction, it is possible to obtain a solution containing the generated fine particles by washing an appropriate porous body portion or dissolving the porous body. When dissolved in a polymer or the like as a reactor, after the reaction, it is possible to obtain a solution containing the generated fine particles by dissolving a solid material such as the polymer.

[Embodiment 3]
Embodiment 3 of the nanoparticle production apparatus of the present invention will be described. The nanoparticle production apparatus of the present invention has basically the same structure and the same operation as that of the first embodiment, and uses the microreactor 19 described below instead of the microreactor 1. Here, a different part from Embodiment 1 of the nanoparticle manufacturing apparatus of the present invention described above will be described.

[Thin tube type microreactor 19]
The microreactor 19 shown in FIG. 4 includes a plurality of capillary tubes 2 for rectifying a plurality of solutions and feeding them into the fine flow path 3, and a fine flow path 3 in which these multiple solutions are mixed in a laminar flow state to cause a chemical reaction. This is a thin tube type microreactor composed of a discharge tube 4 and the like for discharging a reaction product after reaction and a reaction residual solution. A plurality of capillary tubes 2 are respectively connected to one end face of the micro flow path 3. The rough shape of the microchannel 3 is a slow funnel-shaped cone, and a plurality of capillary tubes 2 are connected to the bottom surface thereof. The central axes of the capillary tubes 2 are arranged so as to be parallel to each other. One end of the discharge pipe 4 is fixed to the top which is the other end of the fine flow path 3. The diameter of the bottom surface of the microchannel 3 of the third embodiment is 3.5 mm, the height is 1 mm, and the top diameter is 0.5 mm.

  The top of the fine channel 3 preferably has a cross-section in the range of 1 μm to 1 mm in diameter. When the diameter is reduced in this way, the volume ratio with respect to the surface area of the solution passing through the fine flow path 3 is reduced, and heat applied from the outside by heating can be uniformly transmitted to the whole in a short time. Therefore, there is an advantage that the heating control of the reaction becomes easy. Moreover, if it is reaction at room temperature, it may be basically a laminar flow region having a Reynolds number of 2100 or less. However, also in this case, from the viewpoint of mixing efficiency by diffusion mixing, it is desirable that the diameter of one unit of the flow generated in the fine flow path 3 is 150 μm or less.

  In general, when a solution is injected into a linear tube and allowed to flow at a relatively low flow rate, a solution in which the solution flows as a line parallel to the tube axis is a laminar flow. When the flow velocity in the tube increases, the flow velocity of the solution becomes locally irregular and changes from laminar flow to turbulent flow. This turbulent flow is considered to be a variation in the flow rate distribution of the reaction solution caused by friction between the reaction solution and the inner wall of the tube. Backmixing due to turbulent flow causes variations in the reaction time of the solution, which makes it difficult to narrow the particle size distribution of the reaction product.

  Therefore, the flow of the solution in the microchannel 3 of the third embodiment is a laminar flow, and a chemical reaction is performed by diffusion between adjacent laminar solutions to generate nanoparticles. For this purpose, it is important to control the flow rate so as not to cause turbulent flow in the fine flow path 3. This flow rate control is expressed by the Reynolds number, which is a parameter expressed by the ratio between the inertial force and the viscous force of the liquid flowing in the fine channel 3, and can be handled quantitatively.

This Reynolds number Re is expressed by the following equation depending on the diameter of the microchannel 3 and the flow velocity and viscosity of the liquid flowing therethrough.
Re = VL / ν (Formula 1)
However, V [m / s] is a typical fluid velocity, L [m] is a pipe diameter, and ν [m ² / s] is a kinematic viscosity coefficient.

  The injection flow rate of the solution in the microchannel 3 is desirably a laminar flow region where the Reynolds number (Re) in the microchannel 3 is 2100 or less. In general, although it varies depending on the viscosity, flow rate, and temperature of the solution, if the Reynolds number in the fine channel 3 exceeds 2100, backmixing due to turbulent flow increases, making it difficult to narrow the particle size distribution. Further, when the tube diameter is smaller than 1 μm, it becomes difficult to handle as a manufacturing apparatus, and the pressure loss in the apparatus increases during operation, and the production efficiency decreases.

The mixing speed by the diffusion of the solution under laminar flow can be obtained using the following Peclet number Pe.
Pe = Dt / L ² (Formula 2)
However, D [m ² / s] is a diffusion coefficient, t [s] is time, and L [m] is a length (tube diameter) for diffusion.

For complete mixing, the condition is that the Peclet number Pe is 1, and the time t is t <L ² / D (Equation 3)
Mix thoroughly in time. The diffusion coefficient D can be roughly calculated by the following Stokes-Einstein equation.
D = kT / (6πηα) (Formula 4)
Where k [J / K] is the Boltzmann constant, T [K] is the absolute temperature, η [Pa · s] is the viscosity coefficient, and α [m] is the particle diameter.

In Equation 4, the diffusion coefficient D is inversely proportional to the particle size α. For example, the diffusion coefficient D of a molecule having a size of 0.3 nm (particle diameter α =) in water is about 10 ⁻⁹ m ² / s. When (particle diameter α =) 3 nm, the diffusion coefficient D is 10 ⁻¹⁰ m ² / s. From this, the layer width for complete mixing in 2 seconds is 30 μm at 0.3 nm and 10 μm at 3 nm. Therefore, in the case of a low molecule (size of about 0.3 nm), a layer thickness of 30 μm or less is desirable for a reaction that is completed in 10 seconds or less.

  The layer thickness of the raw material solution can be controlled by selecting a thin tube through which the raw material solution flows, but can be changed depending on the flow rate ratio. When the flow rate from a certain thin tube is made slower than the flow rate of other thin tubes, the film thickness decreases, and conversely, the flow rate increases to increase the thickness. A plurality of solutions are reacted in the micro flow path 3, and the reaction product and the reaction residual solution are taken out into the atmosphere through the discharge pipe 4, and collected in a collector (not shown) or the like.

  FIG. 5 is a conceptual diagram showing a cross section of a plurality of solutions flowing through the fine channel 3. As is clear from this conceptual diagram, the solution flowing from the plurality of capillary tubes 2 to the microchannel 3 is arranged in the same manner as the plurality of capillary tubes 2 while being supplied to the bottom surface of the microchannel 3. It becomes a laminar flow and has a two-dimensional arrangement. The cross-sectional view shown in FIG. 4 represents the capillary tubes 2 with numbers 1 to 14 in order.

  Separate solutions are respectively supplied from the capillary tube 2, mixed in the microchannel 3, pass through while maintaining a laminar flow, cause a reaction, and are led to the discharge tube 4. At this time, the flow of each solution is a laminar flow in the microchannel 3. Since the flow of each solution is laminar, a chemical reaction basically occurs only between adjacent laminar flows.

  It is possible to control the chemical reaction by supplying a solution to the capillary tube 2 so as to form a pattern in the cross-sectional view of the microchannel 3. For example, a precursor-containing solution can be supplied to the capillary tubes 2, 13, 8, 10, and 10 shown in the cross-sectional view of the microchannel 3, and a solution that does not contain the precursor can be supplied to the other capillary tubes 2. The grasping instrument 11 is substantially the same as the above-described embodiment, and the description thereof is omitted.

  Next, the present invention will be described in more detail with reference to Example 1, but the present invention is not limited to these examples. In Example 1, a single glass capillary was used as a microreactor. The inner diameter of the glass capillary is 0.2 mm. This glass capillary was filled with a solution containing cadmium stearate 70 g / kg, trioctyl phosphate oxide 300 g / kg, trioctyl phosphate selenide 90 g / kg, trioctyl phosphate 280 g / kg, and stearic acid 260 g / kg.

  A portion of 40 cm from the glass capillary filled with this solution is immersed in an oil bath maintained at a temperature of 275 ° C., and is passed through the oil bath for 30 seconds while pulling from one side of the glass capillary. The solution was allowed to react. When the glass capillary was immersed in an oil bath, it was heated rapidly and the reaction of the solution in the glass capillary started.

  When the glass capillary came out of the oil bath, it rapidly cooled and the reaction of the solution in the glass capillary stopped. Next, the reaction mixture was rapidly cooled and collected, and the particle size of the cadmium selenide nanoparticles produced was determined by measuring the UV-VIS absorption spectrum after dilution in toluene. Furthermore, the particle size distribution of the product was measured by TEM observation. As a result, CdSe nanoparticles having an average particle diameter of 3.5 nm and a coefficient of variation of 6% were obtained.

[Comparative Example 1]
Next, Comparative Example 1 of the present invention will be described. In this comparative example 1, a glass capillary to which a syringe with a syringe air pump was connected was used as a microreactor. The syringe was filled with a solution containing cadmium stearate 70 g / kg, trioctyl phosphate oxide 300 g / kg, trioctyl phosphate selenide 90 g / kg, trioctyl phosphate 280 g / kg, stearic acid 260 g / kg. The inner diameter of the glass capillary is 0.2 mm.

  A 40 cm portion from the glass capillary was immersed in an oil bath maintained at a temperature of 275 ° C. The solution in the syringe was introduced into the capillary using a syringe air pump, and the solution in the glass capillary was reacted by passing through a heated portion by an oil bath for 30 seconds. When the solution in the glass capillary reached the heated part by the oil bath, it rapidly heated to start the reaction, and when it left the heated part, it was rapidly cooled by air and stopped.

  Then, the solution after reaction was collect | recovered, the particle size of the cadmium selenide nanoparticle produced | generated by measuring a UV-VIS absorption spectrum after diluting in toluene was calculated | required. Furthermore, the particle size distribution of the product was measured by TEM observation. As a result, CdSe nanoparticles having an average particle size of 3.5 nm and a coefficient of variation of 10% were obtained. The coefficient of variation in the particle size of the produced CdSe nanoparticles was larger than in Example 1 in which the glass capillary filled with the reaction solution was immersed in the oil bath and passed through the oil bath.

  The present invention is preferably used in the field of new material development, the field of biotechnology, and the field of medicine.

FIG. 1 is a diagram illustrating an outline of a nanoparticle production apparatus 10 according to the first embodiment. FIG. 2 is a diagram illustrating an outline of the microreactor 1 according to the first embodiment. FIG. 3 is a diagram illustrating an outline of the nanoparticle production apparatus 30 according to the second embodiment. FIG. 4 is a diagram illustrating an outline of the microreactor 19 according to the third embodiment. FIG. 5 is a cross-sectional view showing the state of the solution flowing through the microchannel 3 of the microreactor 19.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 19 ... Microreactor 2 ... Capillary tube 3 ... Fine flow path 4 ... Discharge pipe 5 ... Syringe connector 6 ... Syringe 7 ... Air pump 10, 30 ... Nanoparticle manufacturing apparatus 11, 32 ... Gripping instrument 12 ... Conveyance path 13 ... Temperature Control part 15 ... Oil bath 16 ... Temperature measuring device 17 ... Control mechanism 20 ... Vertical transfer mechanism 21 ... Piston rod 22, 25 ... Gripping part 23 ... Support shaft 26 ... Recovery soda 31 ... Reactor 33 ... Pulley 34 ... Heating zone

Claims (11)

The reactor characteristic length 1 m to 1 mm, supplying a raw material solution for producing nanoparticles, in a state where the solution is stationary after the solution is introduced into the reactor, the reactor temperature control means A reaction is carried out while relatively moving the reactor and the zone by a conveying means so as to move in the zone controlled in temperature. The method for producing nanoparticles according to claim 1,
The zone is composed of a heating zone whose temperature is controlled by heating up to the start temperature of the reaction, and a cooling zone for quenching the reaction performed in the heating zone,
After the reaction is performed while the reactor and the heating zone are relatively moved by the transport means so that the reactor is transported in the heating zone, the reactor and the cooling zone are The reactor is rapidly cooled while being relatively moved by the conveying means. In the method for producing nanoparticles according to claim 1 or 2,
The reactor is selected from a tube having an inner diameter of the representative length, a line having a diameter of the representative length, a thin film having a thickness of the representative length, and a pore having the representative length. A method for producing nanoparticles, characterized in that it is one fine space. The method for producing nanoparticles according to claim 1, wherein the nanoparticle production method is selected from claims 1 to 3.
The solution is supplied to the reactor to form two or more layers of the solution, and the reaction is performed by a diffusion reaction between the layers. In the method for producing nanoparticles according to claim 1 or 2,
The reactor includes a microchannel having an inner diameter of the representative length, and the solution is added from a plurality of sample supply channels connected to the microchannel to a sum of cross-sectional areas of the plurality of sample supply channels. Supplying in a laminar flow to the fine channel having a smaller cross-sectional area, mixing and reacting in a state where the laminar flow of the solution is maintained, causing the reaction to occur in the fine channel, and then generating a reaction after the reaction An article is discharged from a sample discharge channel connected to the fine channel. The reactor characteristic length 1 m to 1 mm, and the solution supply means for supplying a raw material solution for making nanoparticles,
The reactor for allowing the solution to react with the supply stopped;
Temperature control means for controlling the temperature by heating or cooling the reactor;
A zone temperature-controlled by the temperature control means;
The nanoparticle manufacturing apparatus which consists of a conveyance means for moving relatively with respect to the said reactor. In the nanoparticle production apparatus according to claim 6,
The zone consists of a heating zone for heating the reactor up to the start temperature of the reaction and a cooling zone for quenching the reaction carried out in the heating zone,
The conveying means causes the reactor to alternate between the heating zone and the cooling zone so that the reaction is performed while moving in the heating zone, and then rapidly cooled while relatively moving in the cooling zone. A nanoparticle production apparatus characterized in that a reaction is carried out while moving. In the nanoparticle production apparatus according to claim 6 or 7,
The reactor is selected from a tube having an inner diameter of the representative length, a line having a diameter of the representative length, a thin film having a thickness of the representative length, and a pore having the representative length. An apparatus for producing nanoparticles, characterized in that it is one fine space. In the nanoparticle production apparatus according to claim 6 or 7,
The solution is supplied from the solution supply means to the reactor so as to form two or more layers, and the reaction is performed by a diffusion reaction between the layers. In the nanoparticle production apparatus according to claim 6 or 7,
The reactor consists of the micro-channel of the inner diameter of the characteristic length, a plurality of sample supply passage for supplying at least three kinds of the raw material solution a laminar flow for producing nanoparticles, wherein the sample supply The fine flow channel connected to the flow channel and having a cross-sectional area smaller than the sum of the cross-sectional areas of the plurality of sample supply channels, and after the reaction is performed in the fine flow channel, the reaction product after the reaction is discharged. A nanoparticle production apparatus comprising: a sample discharge flow channel connected to the fine flow channel. In the nanoparticle manufacturing apparatus according to claim 10,
The sample supply channel comprises a capillary,
A syringe connector is connected to one end of the capillary that is not connected to the fine channel,
During the transport, the said solution from the syringe connector is supplied to the capillary, the is arranged a flow in the microchannel two-dimensionally, characterized in that to cause the reaction between the flow adjacent layers Nanoparticle production equipment.

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