JP7086629B2 - Fixed layer reaction device and fixed layer reaction method - Google Patents

Description

Embodiments of the present invention relate to a fixed layer reaction apparatus and a fixed layer reaction method used in a liquid-solid reaction, a gas-liquid solid reaction, a gas-liquid solid catalyst reaction, and the like.

Many systems and methods for liquid-solid reaction, gas-liquid solid reaction, or gas-liquid solid-catalyzed reaction using a fixed-layer reaction device have been proposed so far. The solid filled in the fixed layer refers to a substance or catalyst that contributes to the reaction.
When the fluid is a liquid, the differential pressure accompanying the flow becomes large, a partial passage is formed in the fixed layer, and the fluid flows only there, which tends to cause a problem that the reaction is hindered.

Further, when the fluid contains a gas or when the gas is generated by the reaction, the gas may lift the fixed layer or a partial passage may be formed in the fixed layer.

When a partial passage is formed in the fixed layer, the fluid flows only there, and sufficient reaction time (time for the fluid to pass through the fixed layer) cannot be secured, and the fluid passes unreacted. There is a problem that the number increases.
In order to deal with such a problem, in the conventional fixed layer reaction apparatus, a method has been proposed in which the fixed layer reactor is enlarged in size, a sufficient reaction time is secured, and the fixed layer reaction proceeds smoothly.

Further, a method has been proposed in which the active ingredient of the catalyst is supported on a structure in which fibrous activated carbon is entangled as a fixed layer. According to this method, it is possible to secure a strong space that can sufficiently withstand the pressure of the fluid flow, and it is possible to increase the reaction surface area.
Further, a method has also been proposed in which a liquid phase / gas phase mixture is allowed to flow down into a tubular body called a chimney and uniformly dispersed in a fixed layer (catalyst layer).

In this method, fluid flows from the outside of the tray in which the chimney is installed into the inside of the chimney through the holes provided in the chimney, and flows through the lower through hole of the tray together with the gas having a high flow velocity flowing into the inside of the chimney. By being dispersed in the fixed layer, the fixed layer reaction is carried out.

Japanese Unexamined Patent Publication No. 58-146446 Japanese Patent No. 5661106

In the conventional fixed layer reaction device described above, it is possible to suppress the fixed layer containing the catalyst and the like from being lifted by the increase in the differential pressure due to the fluid, but a passage is partially formed in the fixed layer, and the fluid is the fluid. Since it flows along the passage, there is a problem that the fixed layer reaction is hindered.
In addition, there are problems that the size of the fixed layer reactor becomes large, the cost increases, and the space efficiency deteriorates.

The embodiment of the present invention has been made to solve the above-mentioned problems, and is simple and has high reaction efficiency and can be used for a long period of time because it can suppress the lifting of the fixed layer and the formation of a passage in the fixed layer. It is an object of the present invention to provide a fixed layer reaction apparatus and a fixed layer reaction method.

In order to solve the above problems, the fixed layer reaction apparatus according to the present embodiment is connected to the reaction vessel and the lower part of the reaction vessel, and supplies the reaction vessel with an aqueous ethanol solution and hydrogen peroxide which are the fluids to be treated. A pipe, a discharge pipe connected to the upper part of the reaction vessel and discharging a gas as a reaction product from the reaction vessel, a plurality of pipes arranged in the reaction vessel into which the fluid to be treated flows, and the inside of the pipe. A through hole formed above the pipe in a fixed layer reactor comprising a catalyst filled in the above and a plurality of through holes formed on the outer periphery of the pipe and generating water and gas as reaction products. Is composed of a hydrophilic substance, or the unreacted ethanol aqueous solution and hydrogen peroxide that have been transferred to the outside of the pipe by applying the hydrophilic substance are moved into the pipe and formed below the pipe. It is characterized in that the formed through hole is composed of a hydrophobic substance, or a hydrophobic substance is applied to release the gas from the through hole to the outside of the pipe preferentially over water which is a reaction product. do.

Further, the fixed layer reaction method according to the present embodiment is characterized in that the fluid to be treated is treated by using the fixed layer reaction apparatus according to the present embodiment.

According to this embodiment, the catalyst can be effectively used for a long period of time, the efficiency of the fixed layer reaction can be improved, and the amount of waste catalyst can be reduced. Further, since the structure of the fixed layer reactor can be simplified, it is possible to improve the space efficiency and reduce the cost.

The schematic diagram of the fixed layer reaction apparatus which concerns on this embodiment. FIG. 1 is a cross-sectional view taken along the line AA of FIG.

Hereinafter, the fixed layer reaction apparatus and the fixed layer reaction method according to the embodiment of the present invention will be described with reference to FIGS. 1 and 2.

[Structure of fixed layer reactor]
As shown in FIG. 1, the fixed-layer reaction apparatus 1 according to the present embodiment is detachably attached by a cylindrical reaction vessel 2 and upper and lower partition plates 11 and 12 arranged in the reaction vessel 2 and arranged vertically. A plurality of cylindrical pipes 3 supported by the pipe 3, a catalyst 4 filled in the pipe 3, a supply pipe 5 connected to the lower part of the reaction vessel 2 to supply a fluid into the reaction vessel 2, and a reaction vessel 2. It is composed of a discharge pipe 6 connected to the upper part and discharging the treated fluid or gas to the outside. A large number of through holes 3a smaller than the catalyst 4 are formed on the outer periphery of the pipe 3.

The fluid (in this embodiment, the ethanol aqueous solution 7 and the hydrogen peroxide 8) supplied from the supply pipe 5 into the reaction vessel 2 flows upward in the pipe 3 filled with the catalyst 4, and a chemical reaction occurs in the process. The treated liquid collects in the upper chamber 14 from the through hole 13 formed in the upper partition plate 11 and is discharged to the outside through the discharge pipe 6.

In the example of FIG. 1, the supply pipe 5 is provided at the bottom of the reaction vessel 2 and the discharge pipe 6 is provided at the top, but the present invention is not limited to this, and it depends on the installation mode (for example, horizontal placement) of the reaction vessel 2. May be changed as appropriate.

Further, the gas generated in the reaction process is discharged from the through hole 3a of the pipe 3 to the flow path 10 outside the pipe 3 and gathers in the upper part of the upper chamber 14 from the through hole 13 formed in the upper partition plate 11 and finally. It is discharged to the outside from the discharge pipe 6.

The shape of the reaction vessel 2 is not particularly limited, and a vessel having a cylindrical shape, a rectangular shape, a polygonal shape, or the like can be used. Further, the number, size, shape and the like of the pipes 3 arranged in the reaction vessel 2 can be appropriately changed.

In order to allow the reaction to proceed efficiently, the ratio of the portion occupied by the pipe 3 to the reaction vessel 2 and the portion other than that is the ratio of the volume of the liquid and the volume of the gas generated by the reaction between the aqueous ethanol solution 7 and the hydrogen peroxide 8. It is preferably about 10 to 100 times.

Further, the pipe 3 may be formed of a mesh-shaped or punching metal-shaped pipe to form a large number of through holes 3a.
Further, a hydrophilic or hydrophobic substance may be applied to the plurality of through holes 3a formed on the outer periphery of the pipe 3 depending on the installation location, or the material of the pipe 3 may be hydrophilic or hydrophobic. It may be composed of the substance of. The details will be described later.

Further, a heating device such as a heater for controlling the temperature inside the reaction vessel 2 may be provided on the outer periphery of the reaction vessel 2, and a preheater for heating the fluid may be provided in the supply pipe 5. It may be (not shown).

(Action)
The operation of the fixed layer reaction device and the fixed layer reaction method according to the present embodiment will be described based on the experimental example performed using the fixed layer reaction device 1 described above.

In this experimental example, iron was used as the catalyst 4, and an ethanol aqueous solution 7 and hydrogen peroxide 8 at 95 ° C. were used as the fluid.
In the fluid composed of the aqueous ethanol solution 7 and the hydrogen peroxide 8, the following reaction proceeds in the pipe 3 under the iron catalyst 4.
C ₂ H ₅ OH + 6H ₂ O ₂ → 2CO ₂ + 9H ₂ O (Equation 1)

The generated carbon dioxide (CO ₂ ) is discharged to the outside of the pipe 3 from a large number of through holes 3a formed on the outer periphery of the pipe 3, and passes through the flow path 10 to the through holes 13 and the upper chamber 14 of the reaction vessel 2. Moving. On the other hand, water, which is a reaction product, moves to the flow path 10 through the through hole 3a, is stored in the reaction vessel 2, and then is connected to the discharge pipe 6 or the pipe 15 provided below the side of the reaction vessel 2. It is discharged to the outside as appropriate.
As the above-mentioned reaction proceeds, for example, impurities reduce the activity of the catalyst 4, and the main reaction site moves from the inlet side to the outlet side of the reaction vessel 2.

At the site where the activity of the catalyst 4 is reduced, the fluid composed of the aqueous ethanol solution 7 and the hydrogen peroxide 8 moves to the flow path 10 without reacting, but when it moves to the position where the activity of the catalyst 4 exists, it is in the flow path 10. The gas (carbon dioxide) moves into the pipe 3 again and reacts.

In order to promote the movement of this fluid (ethanol aqueous solution 7, hydrogen peroxide 8) into the pipe 3, a hydrophilic substance is applied to the through hole 3a above the pipe 3, or a pipe containing the through hole 3a. 3 may be composed of a hydrophilic substance.

It is desirable that the through hole 3a having hydrophilicity is formed above the pipe 3 (outlet side), preferably above the center. This makes it possible to effectively utilize the catalyst 4 and improve the efficiency of the reaction.

Further, a hydrophobic substance is applied to the through hole 3a below the pipe 3 in order to preferentially release a gas over water which is a reaction product, or the pipe 3 including the through hole 3a is made hydrophobic. It may be composed of a substance.

It is desirable that the through hole 3a having hydrophilicity is formed below the pipe 3 (inlet side), preferably below the center. This makes it possible to suppress the formation of a fluid passage inside the catalyst 4 and prevent the catalyst 4 from floating.
After the reaction is completed, the pipe 3 and the catalyst 4 are recovered from the reaction vessel 2, and only the catalyst 4 is used as waste and the pipe 3 is reused.

(effect)
As described above, according to the present embodiment, since the generated carbon dioxide goes out of the pipe 3 through the through hole 3a, the floating of the catalyst 4 and the formation of the fluid passage in the catalyst 4 are suppressed. be able to. As a result, the catalyst 4 can be effectively used without being worn, the reaction efficiency can be improved, and the amount of waste generated can be reduced.

Further, since the heat generated by the reaction is less likely to be accumulated in the reaction vessel 2, the number of places where the temperature is locally high is reduced, which makes it possible to prevent the catalyst 4 from deteriorating and to use it for a long period of time.
Further, by making the through hole 3a hydrophobic or hydrophilic, it is possible to promote the gas release from the pipe 3 and the re-inflow of the unreacted fluid into the pipe 3, so that the reaction efficiency can be improved. Further improvement and effective utilization of the catalyst 4 can be further achieved.

Further, since the structure of the reaction vessel 2 is not complicated, the manufacturing cost and the operating cost of the reaction vessel 2 are reduced.
In the above embodiment, the reaction between the aqueous ethanol solution and hydrogen peroxide has been described as an example, but the methanol synthesis reaction with carbon dioxide (CO ₂ ) represented by the formula 2 is described.
CO ₂ + 3H ₂ → CH ₃ OH + H ₂ O (Equation 2)
It can also be used for hydrogen synthesis by steam reforming of dimethyl ether represented by the formulas 3 and 4.
CH ₃ OCH ₃ + H ₂ O → 2CH ₃ OH (Equation 3)
2CH ₃ OH + 2H ₂ O → 6H ₂ + 2CO ₂ (Equation 4)

Although the embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This novel embodiment can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 ... Fixed layer reactor, 2 ... Reaction vessel, 3 ... Pipe, 3a ... Through hole, 4 ... Catalyst, 5 ... Supply pipe, 6 ... Discharge pipe, 7 ... Ethanol aqueous solution, 8 ... Hydrogen peroxide, 10 ... Flow path , 11 ... upper partition plate, 12 ... lower partition plate, 13 ... through hole, 14 ... upper chamber, 15 ... piping

Claims (3)

The reaction vessel, the supply pipe connected to the lower part of the reaction vessel and supplying the ethanol aqueous solution and hydrogen peroxide which are the fluids to be treated to the reaction vessel, and the reaction product connected to the upper part of the reaction vessel and from the reaction vessel. A discharge pipe for discharging a certain gas , a plurality of pipes arranged in the reaction vessel into which the fluid to be processed flows, a catalyst filled in the pipe, and a plurality of through holes formed on the outer periphery of the pipe. In a fixed layer reactor that is equipped with, and generates water and gas as reaction products,
The through hole formed above the pipe is made of a hydrophilic substance, or the unreacted aqueous ethanol solution and hydrogen peroxide that have been transferred to the outside of the pipe by applying the hydrophilic substance are moved into the pipe. The through hole formed below the pipe is made of a hydrophobic substance, or a hydrophobic substance is applied to the through hole to allow a gas rather than water, which is a reaction product, to flow from the through hole to the outside of the pipe. A fixed layer reactor characterized by preferential release . The fixed layer reaction apparatus according to claim 1, wherein the pipe filled with the catalyst is detachably supported by a partition plate in the reaction vessel. A fixed layer reaction method comprising treating a fluid to be treated by using the fixed layer reaction apparatus according to claim 1 or 2.

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