JP2014121703A - Hydrothermal reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit, by heating a vessel for a hydrothermal reactor isotropically and homogeneously, the occurrence of local ebullition and a concentration variation attributed to liquid droplets existing on the reaction solution interface while obliterating the need for agitation and to realize the visualization of a reaction process progressing in the interior of a hydrothermal reactor using a made-of-glass pressure-resistant vessel.SOLUTION: The provided hydrothermal reactor includes a reaction vessel 1a and a hermetic lid 1c for hermetically sealing the reaction vessel, whereas a hydrothermal reaction is induced in the presence of high-temperature, high-pressure hot water by heating the interior space of the former. A heater 5 for heating the profile circumferential surface and bottom surface of the reaction vessel 1a, a heater 13 for heating the hermetic lid 1c, and set pressure impression devices for impressing a set pressure within the reaction vessel 1a (decompression valve 20 and back pressure valve 22) are configured, whereas a tabular member 16 consisting of a chemically inert material having a low heat conductivity is laid on the inner circumferential surface of the reaction vessel 1a so as to compartmentalize a space formed by the interface of a reaction solution filled into the reaction vessel 1a and the lower surface of the hermetic lid 1c.

Description

  The present invention relates to a hydrothermal reaction apparatus used for a hydrothermal synthesis reaction in which a compound is synthesized or a crystal is grown in the presence of hot water of high temperature and pressure.

When a compound is synthesized and crystals are grown in the presence of high-temperature and high-pressure hot water using a hydrothermal reactor, it is possible to synthesize and grow substances that cannot be obtained at room temperature and normal pressure. Such techniques are widely adopted in the chemical industry in general, such as inorganic porous material synthesis, sol-gel method, and laboratory synthesis reaction.
In synthesis and crystal growth using a hydrothermal reactor, various water-soluble raw materials are generally mixed at room temperature, stirred and homogenized, and then hydrothermal reaction is performed using the sol or gel as a starting material. .

Hydrothermal reactors include stirred hydrothermal reactors, hydrostatic hydrothermal reactors, and devices that make it possible to observe hydrothermal reaction processes using heat-resistant glass. A large hydrothermal reaction synthesizer has also been developed.
In Patent Document 1 listed below, an AFI-type aluminophosphate porous self-supporting membrane is prepared by performing a hydrothermal synthesis reaction using a stainless steel autoclave equipped with an inner cylinder of polytetrafluoroethylene (Teflon (registered trademark), hereinafter referred to as PTFE). Is described.
Patent Document 2 below describes that a sample is put into a high pressure cylinder, a high pressure gas is sent to an upper chamber partitioned by a free piston, and the sample is pressurized and heated.
Patent Document 3 below describes that a hydrothermal reaction by microwave heating is visualized by an observation glass tube housed inside a transparent cylinder.

In addition, during the hydrothermal reaction synthesis by the stirring type hydrothermal reactor, the reaction solution dynamically moves by stirring, and the crystal particles that react and precipitate from the aqueous solution are subjected to hydrothermal reaction under hydrostatic conditions to achieve homogenization. Compared to the case of using an apparatus, the crystal size and shape are often different even when the obtained crystal phase is different or even when the same crystal phase is obtained.
Therefore, for example, in the synthesis of a porous crystal zeolite obtained by a hydrothermal reaction, the presence or absence of stirring is usually described in the synthesis procedure.
Non-Patent Document 1 is a collection of recipes for zeolites with various skeletal structures and chemical compositions published under the supervision of the International Zeolite Society. Has been.
Further, in the following Non-Patent Document 2, a small reaction vessel described later is used, liquid mercury is put into the bottom, a reaction solution is introduced into the top, and the reaction with mercury is performed by a method of hermetic / static heating. It is shown that a self-supporting membrane of a zeolite whose framework structure named by IUPAC is MFI is formed at the interface of the solution.

JP 2012-62228 A Japanese Patent Publication No.52-10039 Japanese Patent No. 5049764

Verified synthesis of zeolitic materials (Ed. By H. Robson, (Elsevier)), 2001 Y. Kiyozumi et al., Advanced Materials 8 (1996) 517-520

  In a hydrothermal synthesis reaction, in order to achieve synthesis and growth of a target substance, in general, a sealed small reaction vessel (sometimes called an autoclave or a small pressure vessel) is used. Can be heated to 100 ° C. or higher, and a pressure higher than atmospheric pressure can be applied to the reaction vessel by the water vapor pressure of the reaction solution itself. As a result, the boiling point of the reaction solution rises, and the temperature can be raised to the boiling point determined by the water vapor pressure. However, when the reaction solution injected into the small reaction vessel contains a large amount of volatile organic substances or organic solvents, the pressure may be higher than the water vapor pressure when compared at the same temperature.

  When such a small reaction vessel is used, it is necessary to heat the entire vessel isotropically and uniformly in order to stably perform hydrothermal synthesis. Therefore, in the conventional stationary hydrothermal reactor 1 shown in FIG. 1, a heated atmosphere gas (generally air) is forcedly circulated through a reaction vessel having an inner cylindrical portion made of PTFE by a blower fan 2, a heater 3, and the like. It is possible to realize isotropic heating by storing and standing in a stirred heating oven. Reference numeral 4 denotes a thermocouple for measuring the temperature inside the oven and controlling it to a constant temperature, and the arrows schematically represent the air flow inside the oven.

Such isotropic and uniform heating with a heating oven is realized in a thermal equilibrium state. Immediately after the reaction vessel is introduced into the heating oven, it is in the process of raising the temperature. Also in the reaction solution, temperature unevenness occurs.
1 and subsequent drawings, the mechanism (gasket, O-ring, bolt, clamp, etc.) that is interposed between the sealing lid of the reaction vessel and the reaction vessel main body and seals the inside is omitted. doing.

  On the other hand, from the viewpoint of mass production, when the capacity of the reaction vessel is increased, the pressure resistance required for the reaction vessel is greatly increased. For this reason, it is necessary to increase the thickness of the stainless steel and the like, the weight of the reaction vessel increases rapidly, not only the portability is impaired, but also the heating oven has to be increased in size, and a large capital investment, Space is required, and it takes a long time to reach a thermal equilibrium state.

Therefore, in the hydrothermal reaction apparatus 1 shown in FIG. 2, a method of attaching a heater directly to the side peripheral surface and bottom surface of a cylindrical reaction vessel 1a made of stainless steel or the like, or a mantle heater 5 adapted to the outer shape of the reaction vessel 1a. The method of heating from the side peripheral surface and the bottom surface of the reaction vessel is usually employed, and this type of heating reaction apparatus is commercially available from many domestic and foreign manufacturers.
In FIG. 2, an inner cylinder 1b made of PTFE is provided inside a cylindrical reaction vessel 1a, and the reaction vessel 1a is sealed in a sealed state by a sealing lid 1c. A safety valve 10 with a sheath-like pipe 6a for inserting a thermocouple 6 for temperature measurement, a gas introduction / discharge valve 7, a stirring rod 8 and a pressure gauge 9 is attached to the sealing lid 1c. It has been.

The gas introduction / discharge valve 7 is a service valve for filling, for example, a gas necessary for synthesis into the reaction vessel 1a, and is normally closed in the hydrothermal reaction step.
However, in such a heating device, the heating surface by the mantle heater 5 is limited to the side peripheral surface and the bottom surface of the reaction vessel 1a, and the sealing lid 1c is not heated. The temperature difference between the portion directly in contact with the bottom surface and the interface becomes extremely large, and isotropic and uniform heating is impossible.

Therefore, for the purpose of maintaining the uniformity of the temperature and composition of the reaction solution, the temperature and composition of the reaction solution inside the container are made uniform by rotating the stirring rod 8 using a rotation introduction terminal or the like on the sealing lid 1c. Is common.
In addition, when using the heating oven demonstrated in FIG. 1, the method which rotates the container itself in oven and raises the uniformity of not only the temperature of a reaction solution but a composition is also examined.

Generally, if the reaction solution is stirred in the course of the reaction, the temperature and composition of the reaction solution can be made uniform. However, since the reaction solution is constantly moving dynamically by stirring, sometimes the reaction solution becomes excessively uniform. There are cases. Therefore, as described in Non-Patent Document 1, the crystal phase obtained by the presence or absence of stirring may be different, or the crystal size and shape may be different even when the same crystal phase is obtained. It often happens.
In particular, as shown in Patent Document 1 and Non-Patent Document 2 described above, synthesis of a film material in which the interface between the reaction solution in a stationary reaction vessel and mercury or air plays an important role in the synthesis process. Then, the flow of the reaction solution accompanying the stirring and the fluctuation of the interface greatly affect the quality of the product, for example, a film.

In order to avoid such an influence, it is conceivable that the hydrothermal reaction apparatus of FIG. However, even in this case, the following phenomenon occurs.
(1) As described above, a sheath-like pipe 6a for inserting the thermocouple 6 for measuring the internal temperature and a pressure gauge 9 for monitoring the internal pressure are disposed on the sealing lid 1c. Heating is not performed sufficiently because it is exposed to the outside atmosphere.
In particular, when the temperature of the sealing lid 1c is lower than the condensation temperature of moisture or other volatile components in the reaction solution, water vapor evaporated from the interface condenses and condenses on the inner surface of the sealing lid 1c, and droplets are formed. Irregular dropping at the interface of the reaction solution causes fluctuations and ripples in the interface. In addition, such dripping of the droplets is temporary, but the component concentration of the reaction solution at the dripping site changes, which also hinders stable hydrothermal reaction.

(2) Although the pressure inside the reaction vessel in the hydrothermal reactor is determined by the water vapor pressure, it is slightly lower than the original water vapor pressure due to the occurrence of dew condensation in the hermetic lid 1c, resulting in a non-equilibrium state at the interface and evaporation. Since the balance of condensation is lost, the reaction solution boils locally, and many bubbles are generated in the reaction solution and from the inner wall of the container.

By the way, in these hydrothermal reactors, as shown in FIG. 2, generally, a pressure resistant reaction vessel 1 a made of stainless steel or the like is made of PTFE which is a chemically inert substance. By fitting the tube 1b and reacting in a nested reaction vessel, the metal vessel is prevented from being corroded by acid or alkali.
However, PTFE polymers are usually white and opaque, and the reaction process cannot be observed directly. Therefore, a hydrothermal reactor using a glass pressure vessel as a reaction vessel that can be observed inside is already on the market, and it is possible to observe the inside as the reaction process proceeds.
Even in the case of a hydrothermal reactor using such a pressure vessel made of glass, as described above, the flow of the reaction solution accompanied by stirring, local boiling, and the addition of irregular condensate dripping the fine reaction solution. Visualization of changes is difficult.

  Therefore, the object of the present invention is to cause local boiling and droplets at the reaction solution interface while stirring is not required by heating the container of the hydrothermal reactor isotropically and uniformly. It is to realize the visualization of the reaction process proceeding inside the hydrothermal reactor using a glass pressure vessel while suppressing the concentration change.

  More specifically, the hydrothermal reaction apparatus of the present invention includes a reaction vessel and a sealing lid that seals the reaction vessel in a hermetically sealed state, and the presence of high-temperature and high-pressure hot water by heating the internal space. A hydrothermal reactor for performing a hydrothermal synthesis reaction underneath, a heater for heating the side peripheral surface and bottom surface of the reaction vessel, a heater for heating the sealing lid, and a setting for applying a set pressure in the reaction vessel In addition to providing a pressure application device, the inner peripheral surface of the reaction vessel is chemically inert so as to partition a space formed by the reaction solution interface filled in the reaction vessel and the lower surface of the sealing lid, and A plate-like member made of a material having a low heat transfer coefficient is placed.

  In the above hydrothermal reaction apparatus, the plate-like member may be placed so that the lower surface thereof is inclined with respect to the horizontal plane, or is chemically inert and has a low heat transfer coefficient on the inner peripheral surface of the reaction vessel. A ring-shaped member made of a material may be fitted and a plate-shaped member may be placed on the ring-shaped member. It is also preferable that the reaction vessel is chemically inert and includes an inner cylinder, and a support portion for mounting the plate-like member is formed on the inner peripheral surface of the inner cylinder. Further, the ring-shaped member or the support portion may be inclined with respect to the horizontal plane, and the plate-shaped member may be formed in a substantially conical shape having a vertex on the upper side.

  Further, another hydrothermal reactor of the present invention includes a reaction vessel and a sealing lid that seals the reaction vessel in a hermetically sealed state, and heats the internal space, thereby allowing high temperature and high pressure hot water to be present. A hydrothermal reaction apparatus for performing a hydrothermal synthesis reaction, comprising: a heater that heats at least one of a side peripheral surface and a bottom surface of the reaction container; and a set pressure application apparatus that applies a set pressure to the reaction container. And a reaction solution storage container for filling the reaction solution is provided inside the reaction container, an aqueous solution for heating the reaction solution is filled outside the reaction solution storage container, and the aqueous solution is supplied by the heater. Is heated indirectly via the reaction solution storage container.

In the above hydrothermal reaction apparatus, when a container lid having a communication path communicating with the inside of the reaction container is provided on the upper surface of the reaction solution storage container, the inside and the outside of the reaction solution storage container have the same atmospheric pressure. This eliminates the need to consider pressure resistance.
In addition, the reaction solution storage container is supported on the bottom of the reaction container via a support base capable of flowing the aqueous solution, and a stirring device and a heater for heating the sealing lid are installed inside the support base. Then, the temperature of the aqueous solution can be made more uniform.
Further, among the components contained in the aqueous solution, at least one of the volatile component or the component that becomes opaque upon heating is made equivalent to the component concentration contained in the reaction solution, so that It is possible to effectively suppress changes in the components of the reaction solution.

According to the hydrothermal reaction device of the present invention, a heater is attached to the hermetic lid, and the temperature of the hermetic lid is at least equal to or higher than the temperature of the reaction solution. By adjusting the pressure, local boiling of the reaction solution can be effectively suppressed even in the heating step. Furthermore, by dividing the space above the reaction solution interface inside the reaction vessel vertically with plate-like members, even when the reaction vessel is enlarged, it is possible to perform static heating in the same way as conventional static hydrothermal reactors. However, rapid, isotropic and uniform heating can be achieved.
In addition to stabilizing the temperature of the space between the plate-like member and the inner surface of the sealing lid, and suppressing vapor directly contacting the inner surface of the sealing lid, not only drastically reduces the occurrence of condensation due to condensation on the sealing lid. Since the water vapor in the space above the reaction solution interface is heated and the water vapor pressure is increased, the local boiling phenomenon of the reaction solution is alleviated and the reaction process can be clearly visualized.

  According to another hydrothermal reaction device of the present invention, the reaction solution stored in the reaction solution storage container is heated indirectly via the reaction solution storage container by heating the aqueous solution on the outer peripheral surface thereof. Thus, the local temperature rise of the reaction solution generated in the heating process can be effectively suppressed, and the boiling phenomenon can be more reliably suppressed.

Schematic of a stationary hydrothermal synthesis reaction method using a completely sealed small pressure vessel. Schematic of the hydrothermal reaction apparatus employ | adopted when a pressure vessel is enlarged. 1 is a schematic view of a stationary hydrothermal reactor according to Example 1. FIG. Schematic of the experimental apparatus based on the Example which attached the observation apparatus. It is the photograph which imaged the inside of the reaction container of the experimental device filled with pure water at normal temperature and normal pressure, (a) shows the whole image (low magnification), (b) shows the water surface (high magnification), (b) The horizontal arrow indicates the liquid level. The photograph which image | photographed the inside of reaction container when the water in reaction container was heated at 180 degreeC with the hydrothermal reaction apparatus which does not have a plate-shaped member etc. It is the photograph which image | photographed the inside of reaction container when the water in reaction container was heated at 180 degreeC with the thermal reactor by Example 1, (a) is a whole image (low magnification), (b) is the water surface (high (Magnification). A photograph of the reaction solution immediately after reaching 180 ° C. A photograph of a self-supporting film obtained through the final process. The figure which shows the result of having collected the X-ray diffraction (XRD) data by a parallel beam method by SmartLab made from Rigaku. The scanning electron microscope image of the product at the time of making the reaction solution which consists of a chemical composition of Example 1 hydrothermally react on stirring conditions. The photograph which image | photographed the case where the boiling generate | occur | produced with the stationary hydrothermal reaction apparatus of Example 1. FIG. 3 is a schematic view of a stationary hydrothermal reactor according to Example 2. FIG. The actual measurement value which shows the relationship between the heating time of the reaction solution by Example 2, and temperature rise. Photographs taken inside the reaction solution storage container according to Example 2 at every elapse of time from the start of heating. A is the start of heating, B is 3 hours, C is 5 hours later, D is 7 hours later, E is 8 The state after time is shown. 3 is a photograph showing an example of a product generated according to Example 2. The photograph which shows the result of having measured an example of the product produced | generated by Example 2 with the powder X-ray-diffraction apparatus.

  Embodiments of the present invention will be described below with reference to the drawings.

[Example 1]
The configuration of Example 1 is shown in FIG. In addition, about the part which is common in the conventional hydrothermal reaction apparatus demonstrated using FIG. 2, the same code | symbol is attached | subjected and description is abbreviate | omitted.
The basic configuration of the hydrothermal reactor 1 is the same as that shown in FIG. 2, but there is no problem even if a reaction vessel made of tempered glass having excellent heat resistance and pressure resistance is used for visualization.
Compared with the conventional hydrothermal reactor, the difference is that a heating device is provided in the sealing lid 1c, a plate-like member is provided in the reaction vessel internal space above the solution, and further, gas introduction / discharge is performed. A set pressure application device is provided which applies a steady pressure to the internal space of the reaction vessel 1a through the valve 7 and allows the excess pressure to be released through the back pressure valve and the gas discharge pipe.
Hereinafter, Example 1 will be described in detail.

  In FIG. 3A, a silicon rubber heater 13 and an aluminum plate 14 are laminated on the upper surface of the sealing lid 1c, and the upper surface is further covered with a heat insulating sheet 15 used for an automobile muffler or the like. In addition, as shown in FIG.3 (b), the pipe of 12 in a figure is a pipe connected to the back pressure valve 22 which releases excess pressure via the gas discharge pipe 23, and the pipe 11 is shown in FIG.3 (c). ), The gas introduction / discharge valve 7 is connected via a pressure reducing valve 20 to a pressure cylinder 19 filled with a gas such as air or nitrogen. A gas can be supplied from 19 to apply a steady pressure to the internal space of the reaction vessel 1a.

By appropriately adjusting the back pressure valve 22 shown in FIG. 3B and the pressure reducing valve 20 shown in FIG. 3C, a stable constant pressure can be obtained while suppressing local boiling, and an abnormal pressure rise can be suppressed. It is effective in both aspects of safety.
For example, if the reaction solution temperature and internal pressure of the reaction vessel 1a in a steady state, which is optimal for a specific hydrothermal reaction, are known in advance, the pressure cylinder 19 is used in parallel with the heating by the mantle heater 5 and the silicon rubber heater 13. The applied pressure may be adjusted by the pressure reducing valve 20.
The heating means is not limited to the silicon rubber heater as long as the temperature of the sealing lid 1c can be increased to the target temperature. Further, the heat insulating sheet 15 is not limited to the sheet shape. Further, a variable displacement compression pump or the like can be used instead of the pressure cylinder 19.

On the other hand, a plate-like member 16 that divides the upper space of the reaction solution interface up and down is placed on a plate receiver 17 made of a ring-like member or the like above the inside of the stainless steel reaction vessel 1a. Note that it is desirable that both the plate-like member 16 and the plate receiver 17 are made of a material that is chemically inert, such as PTFE, and has a low heat transfer coefficient.
The plate receiver 17 has various forms, such as a ring-shaped member coated with PTFE, a pillar standing from the bottom of the PTFE inner cylinder 1b, or a PTFE inner cylinder 1b. The convex part etc. which were formed by giving a cutting process to the internal peripheral surface of this are mentioned.

  In addition, when using the ring-shaped member coat | covered with PTFE, the plate-shaped member 16 is supported by frictional force by fitting to the internal peripheral surface of the reaction container 1a. On the other hand, when the inner shape is special or when it is a complete cylinder, this plate-like member can be installed by raising a pillar from the bottom of the reaction vessel. When the inner wall of the reaction vessel is made of a material such as PTFE, the plate-like member may be attached by processing the PTFE wall directly.

In general, PTFE has an extremely low heat transfer rate and very high water repellency compared to stainless steel or the like. Therefore, the space formed by the upper surface of the plate-like member 16 and the inner surface of the sealing lid 1c is stably heated by the silicon rubber heater 13 attached to the upper portion of the mantle heater 5 and the upper surface of the sealing lid 1c. In this state, the temperature is maintained at the set temperature, and the temperature of the reaction solution is reliably suppressed to be equal to or lower than the condensation temperature of water and other volatile components. In addition, although the mantle heater 5 is employ | adopted as a heating apparatus, if heating is implement | achieved, there will be no problem even if it uses another heater apparatus.
Moreover, since the upper space of the reaction solution interface is partitioned by the plate-like member 16, it can be efficiently heated by the mantle heater 5 and the temperature difference from the side surface of the aqueous solution can be reduced, and the stationary state shown in FIG. As close as possible to the synthesis environment.

On the other hand, the plate-like member 16 also has its upper space above the reaction solution interface maintained at the condensation temperature or higher. Therefore, in a steady state, condensation and condensation are limited even on the lower surface facing the reaction solution interface. .
Of course, since it is only placed on the plate receiver 17, the vapor generated by heating the reaction solution from below pushes up the plate member 16 and passes between the outer edge and the plate receiver 17. However, the amount is very limited. For this reason, condensation and condensation on the upper surface of the plate-like member 16 and the lower surface of the sealing lid 1c are also dramatically reduced. Even if dew condensation occurs on the upper surface of the plate-like member 16, the droplet eventually inserts the outer edge of the plate-like member 16 or the sheath-like pipe 6 a for inserting the thermocouple 6. Since it is heated and vaporized by the PTFE inner cylinder 1b or gently flows into the reaction solution, the fluctuations of the interface due to the condensation droplets falling due to condensation, undulations, local reaction solution The change of a general component density | concentration can be suppressed effectively.

In order to more effectively suppress the influence of condensation and dew condensation on the upper surface of the plate-like member 16 and the inner surface of the sealing lid 1 c and the lower surface of the plate-like member 16, the plate receiver 17 is slightly inclined with respect to the horizontal plane. An arrangement of the O-ring coated with PTFE and the convex portion cut into the inner peripheral surface of the PTFE inner cylinder 3 are inclined. Thereby, the dew adhering to the upper surface and the lower surface of the plate receiver 17 flows downward along the inclination of the plate receiver 17 while droplets gradually grow due to the water repellency of the PTFE material, and the PTFE inner cylinder 1b. It can be heated and vaporized.
The same effect can also be obtained by forming a convex portion on the outer edge of one of the plate-like members 16 with the plate receiver 17 formed horizontally, or by forming a conical shape having an apex on the upper side. it can.

  Further, as shown by a broken line in FIG. 3, a rain gutter-like convex portion that descends to the right is formed below the plate-like member 16 so that it falls from the outer edge of the plate receiver 17 and is made of PTFE inner cylinder 1b. By receiving droplets that could not be completely vaporized even when they reached the point, and allowing them to flow along the PTFE inner cylinder 1b, they can be reliably vaporized without being dropped as droplets.

In order to verify the effect of the example, as shown in FIG. 4, a CCD camera equipped with a low-power lens 24b capable of observing the entire reaction container, and a high-power magnification capable of observing minute changes near the water surface. Two systems of observation devices comprising a CCD camera with a lens 24a attached thereto were attached.
As the reaction vessel 1a, a pressure resistant glass industry hyperglaster TEM-V1000N (internal volume 1 liter) is used, and instead of the mantle heater 5, this glass reaction vessel outer wall (side peripheral wall and bottom surface) is used. Heating was performed by energizing the uniformly applied heating film (tin oxide film or the like) 5a.
The explosion-proof case 28 surrounding the reaction vessel 1a is provided with a viewing window 28a as an observation window made of heat-resistant tempered glass or the like.
As a reference to be used as a reference for viewing the performance of the apparatus, pure water was observed in a non-stirring environment under conditions of normal temperature (about 27 ° C.) and normal pressure (0.1 MPa). Next, the present embodiment and the plate-like member 16 are removed, the pressure adjustment by the pressure cylinder 19, the pressure reducing valve 20, and the back pressure valve 22 is deactivated. The state of pure water in the reaction vessel was observed.

FIG. 5A is a photograph of the entire reaction container in the normal temperature environment of this example. FIG. 5B is a photograph taken by enlarging the liquid surface. In the following, in the enlarged image of the entire container and the liquid level, it can be seen that the position of the CCD camera used for photographing is common, and of course, the water level does not boil and the liquid level is still at room temperature.
However, not only when the sealing lid 1c is not heated by the silicon rubber heater 13, but also when it is heated, if the plate-like member 16 and the pressure application device are not provided, as shown in FIG. It can be seen that when water is heated to 0 ° C., water vapor is violently boiled from the bottom and sides of the reaction vessel.
Further, not only water condensed on the lower surface of the sealing lid 1c propagates along the inner wall surface, but also condensed water drops that directly fall from the sealing lid 1c. This is because a large amount of water vapor is released to the upper space by boiling. This phenomenon becomes more apparent when the silicon rubber heater 13 is not heated. Along with the occurrence of these phenomena, the liquid surface was observed to shake violently. Further, as shown in FIG. 6 (b) in which the state of the liquid surface is enlarged, it is extremely difficult to observe the water surface.

On the other hand, while heating the sealing lid 1c by the silicon rubber heater 13 and adjusting the applied pressure by the pressure cylinder 19, the pressure reducing valve 20, and the back pressure valve 22 based on the present embodiment, the water is similarly heated to 180 ° C. FIG. 7 (a) shows the state of the entire reaction vessel. In addition, the pressure application by air, water vapor | steam, etc. was 0.98 Mpa, and the heating temperature of the sealing lid 1c was 200 degreeC.
The water in the reaction vessel in this case is still as shown in FIG. 5 (a), which is a case of normal temperature and normal pressure, as can be confirmed from FIG. 7 (a), and boiling is completely suppressed. Yes.

  On the other hand, in FIG. 7B showing the liquid level portion, the liquid level is rising from the normal temperature state, but the state where the liquid level can be clearly observed is maintained as in FIG. 5B. In the actual machine, it is necessary to consider the arrangement of the two CCD cameras with the high-power lens 24a attached, considering the volume expansion and the liquid level rise of the reaction solution accompanying heating. .

Next, a mixed solution having the following molar ratio was prepared as a mixed solution described in Patent Document 1, that is, a reaction solution.
Al ₂ O ₃ : P ₂ O ₅ : (C ₂ H ₅ ) ₃ N: H ₂ O = 1: 1: 3: 225
This solution was adjusted to pH 2.95 by dropwise addition of sulfuric acid. And this solution was put into the reaction container of this invention apparatus, the solution temperature was raised from room temperature to 175 degreeC over about 3 hours, and it hold | maintained at the temperature for 20 hours.
FIG. 8 is a photograph of the reaction solution immediately after reaching 175 ° C. As in the previous experimental results, it can be seen that the solution is in a stationary state without boiling. After completion of the heating, the temperature was lowered to room temperature by natural cooling, and then the product in the reaction vessel was taken out, washed with ultrapure water, and dried in an oven heated to 40 ° C.

FIG. 9 shows a self-supporting film obtained by the above-described operation. Since it is a thin film, some cracks are generated at the time of taking out, but it can be confirmed that a large-area free-standing film is formed.
Further, in order to specify the crystal phase of this film, FIG. 10 shows the result of collecting X-ray diffraction (XRD) data by the parallel beam method by Rigaku Smart Lab. This XRD pattern is equivalent to the example of Patent Document 1, and an AlPO ₄ -5 crystal having an AFI type structure in IUPAC notation forms a free-standing film, and the 002 diffraction line is relative to the other diffraction lines. This indicates that the c-axis is oriented in a direction perpendicular to the film.

On the other hand, when the hydrothermal reaction is performed while rotating the reaction vessel of FIG. 1 described above at a rotation speed of 20 rpm while stirring the above-described solution, the 10 μm as shown in the scanning electron microscope image of FIG. Less than hexagonal columnar crystals are obtained as powder. The fact that a self-supporting film could not be obtained, even if it was obvious to some extent, did not have aggregates, and the crystal form was clearly different from the reaction in a hydrostatic field, such as small crystals one by one.
From the above, it was confirmed that the hydrothermal reaction apparatus according to the present example also functions in the same manner as an autoclave of a type that is introduced into the oven and allowed to stand.

When actually observing a reaction solution in a still water state, in addition to adopting a glass container as a hydrothermal reactor, the entire reaction container excluding the one with a visible light transmission window and the sealed lid needs to be pressure-resistant transparent glass. There is. In general, a glass reaction vessel has an explosion-proof structure for safety measures, and has a specification in which a metal box and an observation window are provided on the outer side of the glass reaction vessel.
Therefore, in the observation of the reaction solution, it is difficult to observe the local region in the aqueous solution using a microscope system using an objective lens having a normal working distance (focal length).

For this reason, a lens system with a long working distance is used.In general, with a long-acting lens, the numerical aperture becomes small, so the image becomes dark and the spatial resolution decreases. ) Has deep characteristics.
In particular, a deep depth of focus is effective in observing a target reaction phenomenon such as a crystal precipitation process in high magnification observation. This is because, as shown in FIG. 4, in order to reliably observe crystal precipitation within a limited field of view, it is advantageous to expand the volume region of the observable reaction solution and increase the depth of focus. It is.

  In this case, the reaction solution is preferably transparent or translucent. Furthermore, generally, when crystal precipitation occurs, if the density of the crystal is higher than that of the aqueous solution, the crystal is precipitated at the bottom of the aqueous solution. In order to track the growth process of an arbitrary crystal, a fixed point observation type observation system is not desirable, and as shown in FIG. 4, at least in the vertical (z-axis) direction, preferably in the horizontal direction (x-axis), the role of focus position adjustment It is desirable to have a three-dimensional lens adjustment system in the front-rear (y-axis) direction.

In installing such an observation lens three-dimensional direction adjustment system, it is desirable that the observation system is lightweight and that the relative positional relationship with the reaction vessel is not affected by vibration or the like. That is, by attaching the observation system directly to the reaction system as shown in FIG. 4, it is easy to ensure the relative positional relationship against vibration and the like.
In addition to local region observation, the entire reaction solution observation system using a low-magnification / fixed-point observation system for confirming which local region is being observed as shown in FIG. Is also desirable. Depending on the purpose, it is also preferable to select a plurality of observation systems such as an observation system using infrared light, or an appropriate one of them.

At this time, if a two-stage pressure reducing valve is employed as the pressure reducing valve 20, it is difficult to be affected by the primary pressure, and a more stable pressure can be obtained.
Further, from the viewpoint of ensuring constant pressure control and ensuring safety, not only control by the pressure reducing valve 20 on the pressure application side, but also a back pressure valve 22 capable of adjusting the pressure value is similarly shown in FIGS. Arbitrary pressure values can be stably obtained by mounting on the top.

In addition, when a two-stage pressure reducing valve is used as the pressure reducing valve 20, a normal pressure reducing operation in which the pressure of the gas that has passed through the pressure reducing valve 20 rises above the set pressure when the internal pressure (primary pressure) of the cylinder 19 decreases. The characteristics of the valve can be suppressed.
Since hydrothermal reaction is frequently performed for a long time (24 hours or more), it is possible to improve safety by applying a constant pressure that does not vary with time in the reaction vessel. it can. Of course, if the pressure rises and exceeds the set pressure, the back pressure valve 22 releases excess pressure from the gas discharge pipe 23, and the pressure in the reaction vessel is maintained at the set pressure upper limit. This is a double safety measure.
However, all devices require careful attention to the introduction of pressure from the viewpoint of ensuring safety, such as precise control of pressure and the use of an explosion-proof structure.

[Example 2]
As described above, in Example 1, in order to realize synthesis and growth of a required substance, even if the reaction solution in the reaction vessel 1a is increased to the boiling point or higher, boiling generated inside can be effectively suppressed. it can.
However, when an experiment was conducted using various reaction solutions and heating conditions, for example, when the same concentration of aluminum or the like as in Example 1 was contained in the reaction solution, the apparatus configuration of Example 1 In cases where a thicker self-supporting film is produced, it has been confirmed that the desired synthesis and growth cannot be realized.
This is considered to be caused by the fact that when the reaction solution is heated to a desired temperature equal to or higher than the boiling point, the reaction solution starts to gel during the heating step and the viscosity rapidly increases.

  The temperature in the reaction vessel 1a rises as the amount of heat from the silicon rubber heater 13 and the mantle heater 5 propagates to the reaction solution by convection, heat conduction, and radiation. However, for example, when aluminum or the like is contained in the reaction solution at a high concentration, the reaction solution starts to gel as the temperature rises. For this reason, the viscosity of the reaction solution rises rapidly, and in particular, convection that has a large influence on heat propagation is greatly reduced. The increase in the viscosity of the reaction solution generated in the heating step makes the temperature distribution of the reaction solution in the reaction vessel 1a non-uniform and inhibits the synthesis and growth of required substances. That is, in the case of the apparatus configuration of Example 1, it occurs in the temperature rising process with uneven temperature between the inner wall portion of the reaction vessel 1a close to the silicon rubber heater 13 and the mantle heater 5 and the central portion in the reaction vessel 1a, It can be presumed that the occurrence of fluctuations in the temperature distribution of the reaction solution is the cause of inhibiting the synthesis and growth of the required substances.

  Specifically, as a result of the experiment, it was found that it was the inner wall portion of the reaction vessel 1a that locally became the highest temperature during the heating process. That is, if the reaction solution finally reaches a target high temperature and is controlled so as to maintain the temperature, the entire reaction solution eventually becomes a uniform temperature due to heat conduction, convection, and radiation. However, when the viscosity of the reaction solution increases as the temperature rises, convection is inhibited during heating, and the temperature non-uniformity generated thereby becomes more prominent as the viscosity of the reaction solution increases.

Furthermore, in the apparatus configuration of Example 1, the thermocouple 6a for temperature measurement is immersed in the reaction solution, but since the distance from the inner wall of the reaction vessel 1a is long, the inner wall of the reaction vessel 1a Dissociation from the actual temperature in the part has occurred.
That is, an overshoot occurs in which the actual temperature of the inner wall portion of the reaction vessel 1a becomes transiently higher than the detected value of the thermocouple 6a for temperature measurement during heating. In the worst case, the inner wall of the reaction vessel 1a This causes a problem that local boiling or disturbance of the reaction solution occurs in the part.
FIG. 12 is a photograph of a case where boiling occurs due to a hydrothermal reaction by the apparatus configuration of Example 1, and an arrow indicated by a is a portion where boiled due to temperature non-uniformity, b The arrows shown indicate cavities generated by the rise of bubbles generated by boiling.

In particular, as described above, the higher the viscosity of the liquid, the higher the temperature non-uniformity, and the larger the overshoot. Such a phenomenon makes it impossible to perform the reaction under static conditions, especially when hydrothermal reactions that require precise temperature control are performed, and has a fatal effect on the synthesis and growth of the required substances. There is a possibility of effect.
In order to suppress such local boiling, it is conceivable to increase the external gas pressure applied from the pressure application pipe 11, but for that purpose, the pressure resistance performance of the entire apparatus including the reaction vessel 1a must be enhanced. In particular, the larger the reaction apparatus, the higher the pressure resistance, leading to an increase in the manufacturing cost of the apparatus.

  Therefore, in this embodiment, as shown in FIG. 13, a reaction solution storage container 30 for storing the reaction solution 29 is provided inside the reaction container 1a filled with the aqueous solution 36 for temperature uniformity, and the temperature is made uniform. By stirring the aqueous solution 36 for the purpose, the inner wall of the reaction solution storage container 30 is heated uniformly, and local boiling is effectively suppressed.

Hereinafter, the apparatus configuration of the second embodiment will be described with reference to FIG. In addition, about the components, apparatus, etc. which are common in Example 1, the same code | symbol is attached | subjected and description is abbreviate | omitted. Also in this example, in order to realize visualization, a reaction vessel 1a made of pressure-resistant glass is used.
A reaction solution 29 which is a raw material for performing a hydrothermal reaction is injected into a reaction solution storage container 30. The reaction solution storage container 30 is preferably made of a chemically stable material that does not react with the reaction solution 29.

For example, if the reaction solution 29 is an acidic solution (excluding hydrofluoric acid), glass can be used as the material of the reaction solution storage container 30, and the reaction solution storage container 30 is made of a metal having high thermal conductivity. In the case of adopting the formation, the surface may be protected by a film such as PTFE.
Even in an alkaline solution, a PTFE coating is effective, and although a stable temperature range is narrower than that of metal or glass, a synthetic resin / polymer material such as polymethylpentene (TPX (registered trademark)) can also be used.

  The reaction solution storage container 30 is fixed to the bottom surface of the reaction container 1 a via a support base 31. This support base 31 is also made of a material having a low heat transfer coefficient, such as PTFE, and is supported by point contact in order to minimize the contact area with the reaction solution storage container 30, and has a minimum support leg. Those are preferred. Moreover, it is desirable to adopt a lattice or porous structure so that the aqueous solution 36 for temperature uniformity can freely flow through the inside of the support base 31.

  The upper part of the reaction solution storage container 30 is also made of PTFE and sealed with a container lid 33 having a communication path 32 communicating with the inside of the reaction container 1a. Although the material of the container lid 33 is not necessarily PTFE, it has a low thermal conductivity and is chemically low so as not to cause uneven temperature changes due to heat from the sealing lid 1c having the silicon rubber heater 13 disposed on the upper surface. A material made of stable PTFE or coated with PTFE is preferable.

Note that a plate-like member 16 similar to that of the first embodiment is placed above the container lid 33, and the temperature non-uniformity in the vertical direction is further suppressed. In the present embodiment, the plate-like member 16 only needs to be placed on the container lid 33, and unlike the first embodiment, there is no need to provide a mechanism for supporting the plate-like member 16 inside the reaction vessel 1a. .
However, unlike Example 1, since the reaction solution 29 itself is filled in the reaction solution storage container 30, it is not always necessary to place the plate-like member 16 on the upper surface of the container lid 33.
As will be described later, since the reaction solution storage container 30 is uniformly heated from the entire surface, there is very little possibility that condensation will occur on the inner upper surface of the reaction solution storage container 30, but such condensation does not fall directly into the reaction solution 29. As described above, the plate member 16 may be installed above the reaction solution liquid level inside the reaction solution storage container 30.

  On the other hand, the inside of the reaction vessel 1 a is filled with an aqueous solution 36 for temperature equalization so as to cover the outer periphery of the reaction solution storage vessel 30. By heating the aqueous solution 36 by the mantle heater 5 (see FIG. 3) and the silicon rubber heater 13, the reaction solution 29 inside is indirectly heated through the wall surface of the reaction solution storage container 30. In this embodiment, the temperature of the reaction solution 29 is not directly measured by the thermocouple 6 for temperature measurement, but the temperature of the aqueous solution 36 is detected and the aqueous solution is heated to a predetermined temperature.

  A stirrer tip (stirring blade) 34 and a magnet 35 for rotating the stirrer tip (magnetic stirring blade) 34 by magnetic coupling are provided inside the support base 31. The aqueous solution 36 is stirred at a constant speed, and the temperature of the aqueous solution around the reaction solution storage container 30 is adjusted. Make uniform. Thereby, the inner wall part of the reaction solution storage container 30 can be heated uniformly. It is important that the level of the aqueous solution 36 is higher than the level of the reaction solution 29 in the reaction solution storage container 30. This is because the direct heating source of the reaction solution 29 is the aqueous solution 36, so that heating is performed from the surroundings as much as possible to perform uniform heating.

As described above, the bottom surface of the reaction solution storage container 30 is supported by the support base 31. The support base 31 prevents interference with the stirrer chip 33, which is a mechanism for stirring the aqueous solution 36, and is a heating source. It has a function of separating from a certain mantle heater 5 and the reaction vessel 1a which is an external pressure vessel so as not to directly affect the reaction solution storage vessel 30.
In this embodiment, the stirring mechanism is constituted by the stirrer chip 33 and the magnet 34. However, since the purpose is to uniformly stir the aqueous solution 36 and to uniform the temperature thereof, the stirring lid 1c is stirred. A rod insertion port may be provided, and the aqueous solution 36 may be agitated by the lower rotating blade. Depending on the chemical composition of the reaction solution 29, the product obtained by the hydrothermal reaction, and the form and shape (the size of the produced crystal, the thickness in the case of a film, etc.), it is not always necessary to provide a stirring mechanism. .
In the present embodiment, as in the first embodiment, the silicon rubber heater 13 is provided in addition to the mantle heater 5 (see FIG. 3), but the reaction solution storage container 30 is uniformly heated by the aqueous solution 36. Therefore, the silicon rubber heater 13 is not necessarily provided. Further, depending on the components of the reaction solution 29, it may be sufficient to provide a heater on at least one of the side peripheral surface and the bottom surface of the reaction vessel 1a. In particular, if only the side peripheral surface of the reaction vessel 1a is used, the influence of heat transfer by the support base 31 can be reduced.

  Now, since the hydrothermal reaction is usually performed at a temperature of 100 ° C. or higher exceeding the boiling point of the reaction liquid 29, the reaction vessel 1a generally has a pressure-resistant structure using a structure / material having excellent pressure resistance, The internal space is maintained at a high pressure by the sealing lid 1c. On the other hand, since the reaction solution storage container 30 communicates with the inside of the reaction container 1a through the communication path 32 formed in the container lid 33, a large difference between the internal pressure and the external pressure does not occur. There is no problem even if it is a glass container.

However, when the communication path 32 formed in the container lid 33 is formed as described above, it is not necessary to consider the pressure resistance of the reaction solution storage container 30, but the reaction solution 29 and the aqueous solution 36 are placed in the upper space by the communication path 32. Therefore, the chemical composition of the reaction solution 29 may be affected.
That is, when the volatile component of the reaction solution 29 is vaporized by heating, the upper portion of the reaction vessel 1a from the upper space of the reaction solution storage vessel 30 until the volatile component concentration in the space above the liquid surface of the aqueous solution 36 in the reaction vessel 1a is balanced. May cause movement of volatile components into space.
Therefore, the aqueous solution 36 preferably contains at least the volatile component contained in the reaction solution 29 at the same component concentration.

Therefore, the composition of the reaction solution 29 is classified into water, volatile components, and other nonvolatile components. Furthermore, according to the purpose, for example, when the reaction solution storage container 30 is a glass container and an internal reaction can be observed from the outside, it is classified into a transparent component and an opaque component (sol particles, transition metal ions, dye molecules, etc.). .
If the opaque component is non-volatile, the aqueous solution 36 is prepared so as to have the same composition and concentration as the reaction solution 29 except for the opaque component. Thereby, it is possible to greatly suppress the change in the chemical composition during the hydrothermal reaction of the reaction solution 29 while allowing the inside of the reaction solution storage container 30 to be observed.
By doing so, the chemical composition of the reaction solution 29 and the aqueous solution 36 can be brought close to each other and opaque components can be eliminated.

In addition, if there is a component that increases in viscosity with heating in the aqueous solution 36, it functions to inhibit temperature uniformity during the heating process when heated by the mantle heater 5 or the like. Whether it is added or not needs to be examined according to the type of individual hydrothermal reaction.
In some cases, the aqueous solution 36 and the reaction solution 29 may be the same component.

Hereinafter, an experimental example of Example 2 will be described.
In the same manner as in Example 1, AlPO ₄ -5 (structure notation by IUPAC is AFI), which is a kind of aluminophosphate porous crystal, was synthesized.
The molar ratio of the raw materials constituting the aqueous solution in the reaction solution storage container is
Al ₂ O ₃ : P ₂ O ₅ : (C ₂ H ₅ ) ₃ N: H ₂ O = 1: 1: 4: 225 (1)
It was. Furthermore, the pH of this solution was adjusted to 2.95 by adding sulfuric acid.
On the other hand, the molar ratio of the aqueous solution 31 for the purpose of uniform temperature is P ₂ O ₅ : (C ₂ H ₅ ) ₃ N: H ₂ O = 1: 4: 225. (2)
It was.

Since the reaction aqueous solution represented by the molar ratio (1) was milky white, the aqueous solution for heating was made a solution represented by the formula (2) excluding the alumina source from the reaction solution. The solution represented by the formula (2) is a completely transparent solution.
These reaction solutions and heating aqueous solutions were filled in predetermined containers, respectively, and then installed in the hydrothermal reactor 1 as shown in FIG.
Heating was performed from room temperature to 175 ° C. over 3 hours, and maintained at 175 ° C. for 18 hours or more. In order to avoid boiling of the reaction solution and the aqueous solution for heating, first, a pressure of 0.3 MPa was applied at room temperature, and then the temperature was raised after making the system completely closed so that no gas entered or exited. The pressure at 175 ° C. was 0.98 MPa.

FIG. 14 shows the change over time of the temperature of the reaction solution due to heating. FIG. 15 is a photograph of the course of the hydrothermal reaction from the start of heating. A is the start of heating (room temperature), B is 3 hours later, C is 5 hours later, D is 7 hours later, E is 8 The state inside the reaction solution storage container after time is shown.
As can be seen from FIG. 14, the temperature reached 175 ° C. after about 3 hours, but the overshoot was very small and less than 2 ° C. Although a slight boiling occurred in the aqueous solution for heating due to this excessive temperature rise, as shown in FIG. 15B, the reaction solution does not boil inside the reaction solution storage container. As a result, in FIGS. 15C to 15D after 3 hours of heating, the reaction solution maintains a substantially equivalent state in the horizontal direction, and the change in the solution appears significantly only in the vertical direction as the free-standing film is formed.

An example of the product obtained as described above is shown in FIG.
In order to confirm the crystal phase of this product, powder X-ray diffraction data was measured with MXP-3TZ manufactured by Mac Science using Cu-Kα rays. The pattern is shown in FIG. 17, and this result shows that the product obtained clearly has an AFI structure as in Example 1, and is a single phase that does not contain other impurity phases. I know that there is.

  As described above, according to this example, it was confirmed that a uniform temperature rising environment maintaining a stationary state was realized, and the actual solution temperature overshoot when reaching a target constant temperature hardly occurred. It was done. Moreover, it was shown that the container in which the reaction solution is placed does not need to have pressure resistance by making the mechanism for matching the pressure between the reaction solution and the heating solution and the composition of each solution close to each other.

  As described above, according to the present invention, even when the reaction vessel is enlarged, the holding temperature (usually 100 ° C. or higher) for allowing the reaction to proceed while achieving static heating as in the conventional static hydrothermal reactor. ) To achieve isotropic and uniform heating. In addition to stabilizing the temperature of the space between the plate-like member and the inner surface of the sealing lid, and suppressing vapor directly contacting the inner surface of the sealing lid, not only drastically reduces the occurrence of condensation due to condensation on the sealing lid. Since the water vapor in the space above the reaction solution interface is heated and the water vapor pressure is increased, the local boiling phenomenon of the reaction solution is alleviated and the product and aqueous solution can be directly observed, so the synthesis time, etc. Therefore, it can be expected to be widely adopted as a hydrothermal reactor.

1 Hydrothermal reactor 1a Reaction vessel made of stainless steel 1b Inner cylinder made of PTFE 1c Sealing lid 4 Thermocouple 5 Mantle heater 5a Heating coating 6 Thermocouple for temperature measurement 6a Thermocouple sheath 7 Gas introduction / discharge valve 8 Stirring bar 9 Pressure gauge 10 Safety valve 11 Pipe (for pressure application)
12 pipe (for pressure release)
DESCRIPTION OF SYMBOLS 13 Silicon rubber heater 14 Aluminum plate 16 Plate-shaped member 17 Plate holder 19 Pressure cylinder 20 Pressure reducing valve 21 Valve 22 Back pressure valve 23 Gas discharge pipe 24a High magnification lens 24b Low magnification lens 25 Camera 26 Camera position adjustment mechanism 27 Reactor / observation system Common base 28 Explosion-proof case 28a Observation window 29 Reaction solution 30 Reaction solution storage container 31 Support base 32 Communication path 33 Container lid 34 Stirrer chip 35 Magnet 36 Aqueous solution

Claims (11)

A hydrothermal reactor for carrying out a hydrothermal synthesis reaction in the presence of high-temperature and high-pressure hot water by providing a reaction vessel and a sealing lid for sealing the reaction vessel in a hermetically sealed state and heating the internal space There,
A heater for heating the side peripheral surface and bottom surface of the reaction vessel, a heater for heating the sealing lid, and a set pressure application device for applying a set pressure to the reaction vessel are provided, and the reaction vessel is filled. A plate-like member made of a material that is chemically inert and has a low heat transfer coefficient on the inner peripheral surface of the reaction vessel so as to partition a space formed by the interface of the reaction solution and the lower surface of the front sealing lid A hydrothermal reactor characterized in that is mounted.   The hydrothermal reaction apparatus according to claim 1, wherein the plate-like member is placed such that a lower surface thereof is inclined with respect to a horizontal plane.   A ring-shaped member made of a material that is chemically inert and has a low heat transfer coefficient is fitted to the inner peripheral surface of the reaction vessel, and the plate-shaped member is placed on the ring-shaped member. The hydrothermal reaction apparatus according to claim 1 or 2.   The reaction vessel includes an inner cylinder made of a material that is chemically inert and has a low heat transfer coefficient, and a support portion for placing the plate-like member on the inner peripheral surface of the inner cylinder. The hydrothermal reaction apparatus according to claim 1 or 2, wherein the hydrothermal reaction apparatus is formed.   The hydrothermal reaction device according to claim 3 or 4, wherein the ring-shaped member or the support portion is inclined with respect to a horizontal plane.   The hydrothermal reactor according to claim 1, wherein the plate-like member has a substantially conical shape having an apex on the upper side.   The said set pressure application apparatus consists of a pressure-reduction valve interposed between pressure sources, and a back pressure valve which releases the pressure in the said reaction container with a set pressure. The hydrothermal reaction apparatus described in any one of the above. A hydrothermal reactor for carrying out a hydrothermal synthesis reaction in the presence of high-temperature and high-pressure hot water by providing a reaction vessel and a sealing lid for sealing the reaction vessel in a hermetically sealed state and heating the internal space There,
While providing a heater for heating at least one of the side peripheral surface and the bottom surface of the reaction vessel, and a set pressure application device for applying a set pressure in the reaction vessel,
A reaction solution storage container for filling the reaction solution is provided inside the reaction container, an aqueous solution for heating the reaction solution is filled outside the reaction solution storage container, and the aqueous solution is heated by the heater. A hydrothermal reactor characterized in that it is heated indirectly via the reaction solution storage container.   The hydrothermal reaction apparatus according to claim 8, wherein a container lid having a communication path communicating with the inside of the reaction container is provided on the upper surface of the reaction solution storage container.   The said reaction solution storage container is supported on the bottom part of the said reaction container via the support stand in which the distribution | circulation of the said aqueous solution is possible, The stirring apparatus was installed in the inside of this support stand. 9. The hydrothermal reactor described in 9.   The concentration of at least one of the components contained in the aqueous solution, which is at least one of a volatile component or a component that becomes opaque upon heating, is equivalent to the concentration of the component contained in the reaction solution. The hydrothermal reactor according to any one of claims 8 to 10.

Images