JP2003119505A - Method for manufacturing alkali-metal dispersion, and method for dehalogenating persistent halogen compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently manufacture an alkali-metal dispersion, and to efficiently dehalogenate a persistent halogen compound by using the alkali-metal dispersion as a dehalogenation agent. SOLUTION: The method for manufacturing the alkali-metal dispersion includes adding an ultrasonic generator 11 and a cooling and heating device 15 to a vessel 1 for manufacturing the alkali-metal dispersion, and exposing a liquid mixture containing alkali metal and a dispersing liquid to ultrasonic wave generated from the ultrasonic generator 11 in the vessel 1 for manufacturing the alkali-metal dispersion. The method includes, at the same time, controlling a temperature of the mixed liquid into a range of a melting point of the alkali-metal or higher but a boiling point of the dispersing liquid or lower, so as to attain a temperature condition for making a surface tension of the alkali-metal small and a viscosity coefficient of the dispersing liquid small, by using the cooling and heating device 15. The method for efficiently dehalogenating the persistent halogen compounds includes using the alkali-metal dispersion.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for easily producing an alkali metal dispersion in which an alkali metal such as sodium or potassium is made into particles and dispersed in another liquid, and to easily remove a persistent halogen compound. The present invention relates to a treatment method for halogenation.

[0002]

2. Description of the Related Art Alkali metals are used in the production of various chemical industrial products because of their high reducing properties. However, since the alkali metal easily reacts with air or water (including water) due to its high reducing property, it is necessary to handle it carefully so as not to touch the air or water.

On the other hand, in the above manufacturing plant, a reaction occurs in which the alkali metal reduces other substances. In order to obtain as many reaction products as possible per unit time, it is necessary to make the alkali metal fine and take the contact surface area with other substances as large as possible. From the above,
A liquid colloid (called a suspension or a dispersion) in which an alkali metal is made into fine particles and dispersed in a liquid that does not react with another alkali metal may be used instead of the alkali metal. Not only an alkali metal as a simple substance but also an alkali metal dispersion is very useful because it has the properties of the alkali metal being dispersed and is highly reactive.

Since alkali metal has a large surface tension and is poor in dispersibility in a liquid, in the industrial production of an alkali metal dispersion, a molten alkali metal is usually stirred in a liquid. Since large power is required, large-scale equipment is required, and particle size is μm.
A great deal of power is required to obtain a unit dispersion. As an example thereof, a method of dispersing an alkali metal by passing it through an orifice or a spiral flow homogenizer under pressure as described in JP-A-9-209006 is known.

Conventionally, the hardly decomposable halogen compound is an extremely stable substance obtained by substituting some elements of a hydrocarbon compound with halogen elements such as fluorine, chlorine and bromine, and as a substance excellent in electric resistance and fire resistance. Widely used in industry. However, when they are treated as waste and need to be decomposed, they are difficult to decompose due to their properties, and in recent years many decomposition treatment methods have been studied.

The hardly decomposable halogen compound, which has been difficult to decompose, can be easily dehalogenated by using a dispersed alkali metal as a dehalogenating agent.
PCB which is a hardly decomposable halogen compound using a sodium dispersion described in JP-A-9-209006.
The dechlorination method of (polychlorinated biphenyl) is PCB
Is a typical method of decomposing.

[0007]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
As described in Japanese Laid-Open Patent Publication No. 9006, a method is known in which an alkali metal is dispersed under pressure by passing through an orifice or a spiral flow homogenizer. However, in order to obtain the alkali metal dispersion, it is necessary to pressurize the production line,
Manufacturing efficiency considering power is low. Therefore, there is a lot of room for improvement in the manufacturing technology for these alkali metal dispersions.

The first object of the present invention is to produce an alkali metal dispersion having a fine particle size easily and efficiently in an industrially small and simple apparatus.
Another object of the present invention is to easily dehalogenate a hardly decomposable halogen compound by using this alkali metal dispersion as a dehalogenating agent.

[0009]

The object of the present invention to produce an alkali metal dispersion is a method for producing an alkali metal dispersion by dispersing an alkali metal in a liquid that does not react with the alkali metal, which contains the alkali metal. The liquid is heated to a temperature range not lower than the melting point of the alkali metal and not higher than the boiling point of the liquid, and ultrasonic waves are applied to the liquid and the alkali metal in the temperature range to disperse the alkali metal in the liquid and the alkali metal. This is accomplished by making a dispersion.

In the method for producing an alkali metal dispersion of the present invention, during the production of the alkali metal dispersion, the alkali metal dispersion is controlled at a temperature at which the surface tension of the alkali metal is small and the viscosity coefficient of the dispersion liquid is also small. The metal particle size of the body is made smaller and uniform to further improve the dispersion production efficiency. In addition, the vortex homogenizer used as a disperser in the conventional example when manufacturing a dispersion requires a large dynamic device such as a pump because it produces a vortex due to the pressure difference. Although the device is large, on the other hand, for example, an ultrasonic dispersion device using an ultrasonic generator as a disperser has a configuration that does not include a high-frequency power source and a simple and large dynamic device of the ultrasonic generator. ,
The device itself can be miniaturized.

In the dehalogenation treatment method of the present invention, the hardly decomposable halogen compound is brought into contact with the alkali metal dispersion produced by the production method according to claim 1 to produce halogen from the hardly decomposable halogen compound. It is a dehalogenation treatment method of a hardly decomposable halogen compound to be removed.

In the dehalogenation treatment method of the present invention, since the alkali metal dispersion produced by the above production method of the present invention is used as the dehalogenation treatment agent, the alkali metal particle diameter of the dehalogenation treatment agent is small. Since it is uniform and the reaction efficiency with the hardly decomposable halogen compound is high, the dehalogenation treatment of the hardly decomposable halogen compound can be carried out easily and efficiently in a short time with an industrially small apparatus.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The alkali metal for producing the alkali metal dispersion is sodium, potassium, lithium, rubidium, cesium or a mixture or alloy thereof.

On the other hand, the dispersion liquid for producing the alkali metal dispersion may be any liquid so long as the reaction with the alkali metal is inactive, and examples thereof include hydrocarbon compounds (liquid paraffin, vegetable oils and fats, Mineral oils and fats such as kerosene and trans oil, hydrocarbons such as benzene, toluene and xylene), silicon compounds (such as silicon oil), and mixtures thereof are used.

Before dispersing the alkali metal in the dispersion liquid, a dispersant or an agglomeration inhibitor may be added, but a liquid that stabilizes the alkali metal dispersion such as a high-viscosity liquid is used. In this case, it can be carried out without adding a dispersant or an agglomeration inhibitor. In the production of the alkali metal dispersion, it is necessary to arbitrarily set the concentration of the alkali metal, but the concentration is practically about 5 to 50%.

On the other hand, as the hardly decomposable halogen compound,
Typical examples are liquid ones represented by PCB (polychlorinated biphenyl) and PCB mixed oil, and solid ones represented by PBB (polybrominated biphenyl).

A method for dechlorinating a PCB using a sodium dispersion as in the above-mentioned prior art is known. However, there is no mention of decomposing a hardly decomposable halogen compound not only with PCB but also with PCB using not only sodium but also an alkali metal dispersion.

The present invention shows a method suitable for producing an alkali metal dispersion and a dehalogenation treatment method for a hardly decomposable halogen compound using the alkali metal dispersion.

Hereinafter, each embodiment of the present invention will be described more specifically.

(First Embodiment) A first embodiment of the present invention will be described.
This will be described with reference to FIGS.

FIG. 1 is a piping system diagram of an apparatus for producing an alkali metal dispersion and an apparatus for dehalogenating a hardly decomposable halogen compound. FIG. 2 is a flowchart relating to the production procedure of the alkali metal dispersion and the dehalogenation treatment procedure of the hardly decomposable halogen compound. 3 and 4 are diagrams showing changes in surface tension with respect to the temperature of the alkali metal and with respect to the temperature of the dispersion liquid. FIG. 5 is an operation sequence diagram of the heating / cooling device for temperature adjustment.

The equipment configuration of this embodiment will be described below with reference to FIG. 1, and the procedure of this embodiment will be described with reference to FIG.

The first embodiment comprises an apparatus for producing an alkali metal dispersion and an apparatus for dehalogenating a hardly decomposable halogen compound. The apparatus for producing an alkali metal dispersion comprises an alkali metal storage container 31, a dispersion liquid storage container 2
1 and an alkali metal dispersion production container 1 and the like.

The alkali metal 35 is first received from the introduction pipe 32 and temporarily stored in the alkali metal storage container 31. The alkali metal storage container 31 is provided with a cooling / heating device 37, and after adjusting the alkali metal 35 to a predetermined temperature range by the cooling / heating device 37, the alkali metal 35 is delivered to the alkali metal dispersion manufacturing container 1 via the delivery pipe 33. To be done.

On the other hand, the dispersion liquid 25 is first introduced into the introduction pipe 2
2, and is temporarily stored in the dispersion liquid storage container 21. The dispersion liquid storage container 21 is provided with a cooling and heating device 27, and after adjusting the dispersion liquid 25 to a predetermined temperature range by the cooling and heating device 27, the alkali metal dispersion manufacturing container 1 via the delivery pipe 23. Sent to. Here, the above-mentioned “predetermined temperature range” is an alkali metal 35.
The temperature range from the melting point of the above to the boiling point of the dispersion liquid 25 or less.

In this way, in the alkali metal dispersion manufacturing container 1, the alkali metal 35 is supplied from the alkali metal introduction pipe 2 and the dispersion liquid 25 is supplied from the dispersion liquid introduction pipe 3.
Are introduced respectively to store a mixed liquid of the alkali metal 35 and the dispersion liquid 25. Since the stored mixed liquid is not yet the alkali metal dispersion 5 having the predetermined metal particle size of the alkali metal, the ultrasonic dispersion device 10 and the cooling heating device attached to the alkali metal dispersion manufacturing container 1 1
5 is allowed to act on the mixed solution to produce a predetermined alkali metal dispersion 5.

During this production, the alkali metal dispersion 5 is adjusted by the cooling / heating device 15 to a temperature range of the mixed liquid. Here, the above-mentioned “predetermined temperature range”
Means a temperature range from the melting point of the alkali metal 35 to the boiling point of the dispersion liquid 25. Ultrasonic disperser 10
Applies an AC power from the high frequency power supply 12 to the ultrasonic wave generator 11 to emit ultrasonic waves into the alkali metal dispersion manufacturing container 1 and apply ultrasonic waves to the mixed liquid.

The cooling and heating device 15 converts the output of the thermometer 16 inserted in the alkali metal dispersion 5 into a temperature signal by the conversion indicator 17 and produces the alkali metal dispersion through the cooling and heating device control line 18. The temperature inside the container 1 can be monitored.

The dehalogenation treatment device for the hardly decomposable halogen compound comprises a hardly decomposable halogen compound storage container 41, a replacement device 51, a dehalogenation treatment container 61 for the hardly decomposable halogen compound, a pump 68, a separator 70, and a treatment. Liquid storage container 7
1, another processing liquid storage container 81 and the like.

The hardly decomposable halogen compound 45 is first received from the introduction pipe 42 and temporarily stored in the hardly decomposable halogen compound storage container 41. The refractory halogen compound storage container 41 is additionally provided with a drain pipe 44 and a cooling / heating device 47, and after adjusting the refractory halogen compound 45 to a predetermined temperature range by the cooling / heating device 47, the delivery pipe 4
3 is sent to the dehalogenation treatment container 61 of the hardly decomposable halogen compound. Here, the above-mentioned “predetermined temperature range” means that when the hardly decomposable halogen compound 45 is a liquid, or even if it is a solid, it is in the form of particles or powder that can pass through the delivery pipe 43. A temperature range from the melting point or higher to the boiling point of the dispersion liquid 25 or lower. Furthermore, when the persistent halogen compound 45 is a solid and is desired to be delivered to the dehalogenation treatment container 61 as a liquid, the temperature is equal to or higher than the melting point of the persistent halogen compound 45.

The replacement device 51 includes a gas introduction pipe 52, a water introduction pipe 53, a gas delivery pipe 54, and a water delivery pipe 5.
5. A reaction vessel communication pipe 57 is provided. Replacement device 5
1 is responsible for the following four operations. (1) When degassing the dehalogenation treatment container 61, gas is sent from the reaction container communication pipe 57 to the gas sending pipe 54. (2) When the dehalogenation treatment container 61 is filled with the inert gas, the inert gas introduced from the pipe 52 is sent to the pipe 57.
3) When pouring water into the dehalogenation treatment container 61, water introduced from the water introduction pipe 53 is sent to the reaction container communication pipe 57. (4) The amount of water not sent in (3) above
The water is delivered from the water delivery pipe 55. The above four operations are configured so that they can be performed by opening and closing the valves attached to the pipes 52 to 55 and starting and stopping a pump (not shown) incorporated in the replacement device 51.

When dehalogenating the hardly decomposable halogen compound 45 by the dehalogenation treatment apparatus, first, the entire dehalogenation treatment vessel 61 is depressurized by the substitution apparatus 51 to discharge the reaction vessel communication pipe 57 and the gas. After degassing via the pipe 54, an inert gas that does not react with an alkali metal such as nitrogen or argon is introduced from the gas introduction pipe 52,
The entire interior of the dehalogenation treatment container 61 is filled with this inert gas.

The hardly decomposable halogen compound 45 flows into the dehalogenation treatment container 61 through the introduction pipe 62. On the other hand, the alkali metal dispersion 5 flows into the dehalogenation treatment container 61 via the pipe 4 and is mixed with the hardly decomposable halogen compound 45 to form a mixed liquid 65. In order to promote the reaction of the mixed liquid 65, the dehalogenation treatment container 6
A stirrer 66 that stirs the mixed solution 65 in 1 and the mixed solution 65
A cooling / heating device 67 for adjusting the temperature of is attached to the dehalogenation treatment container 61. Further, in the dehalogenation treatment container 61, in order to confirm the dehalogenation treatment status of the hardly decomposable halogen compound in the mixed liquid 65, the mixed liquid 6
A drain pipe 64 having a sampling function is also provided, which guides 5 out of the dehalogenation treatment container 61 and takes it out.

When the hardly decomposable halogen compound 45 reacts with the alkali metal contained in the alkali metal dispersion 5, the alkali metal separates the halogen element from the hardly decomposable halogen compound 45 to form an alkali metal halogen compound. The hard-to-decompose halogen compound 45 from which the halogen element is separated has returned to the hydrocarbon compound that is the raw material of the hard-to-decompose halogen compound.

However, in order to completely dehalogenate the hardly decomposable halogen compound 45, the alkali metal dispersion 5 is excessively mixed with the hardly decomposable halogen compound 45. Therefore, in the treated mixed liquid 65, the alkali metal dispersion 5 remains in addition to the alkali metal halogen compound and the hydrocarbon compound. This alkali metal dispersion 5 reacts with water injected from the water introduction pipe 53 through the substitution device 51 and the reaction container communication pipe 57 to change into an alkali metal hydroxide aqueous solution and hydrogen gas.
The process of reacting excess alkali metal with water by this water injection is called quench. The generated hydrogen gas is degassed to the outside of the device through the reaction vessel communication pipe 57, the replacement device 51, and the gas delivery pipe 54 together with the inert gas that has filled the entire device before the treatment. The amount of water introduced into the replacement device 51 via the water introduction pipe 53 and not sent to the reaction vessel communication pipe 57 is sent to the water delivery pipe 55.

When it is judged by the above sampling that all of the hardly decomposable halogen compounds 45 in the mixed solution 65 have been dehalogenated, this solution (the reaction completion state of the mixed solution 65, that is, the processing solution) is used as the dehalogenation processing container 61. It is pressurized by a pump 68 from a delivery pipe 63 attached to and is delivered to a separator 70. In the separator 70, the treatment liquid is separated into an aqueous solution of an alkali metal hydroxide and a hydrocarbon compound, and sent out to the storage container 71 via the pipe 72 and to the storage container 81 via the pipe 82. The container 71 includes the delivery pipes 73 and 74.
The container 81 is provided with delivery pipes 83 and 84, respectively.

Since the difference in density between the aqueous solution and the hydrocarbon compound is relatively large, the separating liquids 75 and 85 stored in the two containers 71 and 81 are of a density separating system in which the separator 70 utilizes centrifugal force or gravity. If adopted, they can be separated relatively easily. However, the separation method of the separator 70 is not limited to the density separation method. Separated liquids 75 and 85 are stored in containers 71 and 8
When a predetermined liquid amount (constraint liquid amount of the container) in 1 is reached, the liquid is discharged to another container connected to the containers 71 and 81.

As shown in FIG. 2, the above-mentioned configuration and operation are summarized in the procedure 101 for producing the alkali metal dispersion 5 and the procedure 102 for dehalogenating the hardly decomposable halogen compound using the alkali metal dispersion. To be

In the configuration of the first embodiment, the production apparatus for the alkali metal dispersion 5 and the dehalogenation treatment apparatus for the hardly decomposable halogen compound 45 are connected to each other.
1 and 102 may be carried out as a series of procedures, or after carrying out the procedure 101, the procedure 102 may be carried out after a while.

In addition, in this example, the alkali metal dispersion 5 was used.
Since the manufacturing apparatus and the dehalogenation treatment apparatus for the hardly decomposable halogen compound are connected and integrated, the two apparatuses can be compactly integrated. However, the manufacturing apparatus and the processing apparatus may not be communicated with each other, but each apparatus may be independent. In the case where these two devices are independent, the pipe 4 appearing in the present embodiment is divided, and the dispersion delivery pipe is used in the alkali metal dispersion production device and the dehalogenation treatment device for the hardly decomposable halogen compound. Dispersion introducing pipes are provided respectively.

The relationship between the method for producing an alkali metal dispersion employed in the present invention and temperature control will be described below with reference to FIGS. 3 and 4. When an alkali metal dispersion is produced, the size of the alkali metal dispersed and the amount of alkali metal dispersed per unit time (that is, production efficiency) depend on the surface tension of the alkali metal and the viscosity coefficient of the dispersion liquid. .
"Tatsuhiro Ueda: Gas-Liquid Two-Phase Flow-Flow and Heat Transfer-: Yokendo: Tokyo (1989): p148-149", etc., "Dispersion formation condition (equation of critical Weber number ) ”, The dispersion particle diameter d is proportional to the surface tension σ of the alkali metal to be dispersed and inversely proportional to the density ρ of the alkali metal and the square of the alkali metal-dispersion liquid velocity difference Δu. Further, it has been known that the smaller the friction, that is, the viscosity coefficient, acting on the interface between the alkali metal and the dispersion liquid, the larger Δu. Further, when the alkali metal is dispersed by using an ultrasonic generator, the smaller the viscosity coefficient of the dispersion liquid is, the smaller the absorption of ultrasonic waves can be suppressed, and the higher the production efficiency of the dispersion.

From the above, in the production of the alkali metal dispersion, it is necessary to set the surface tension of the alkali metal as small as possible and the viscosity coefficient of the dispersion liquid as small as possible so as to reduce the size of the dispersion. It is important for improving its manufacturing efficiency. Japanese Unexamined Patent Publication No. 9-2090
06 and “Kiyama and Ogawa: PCB dechlorination decomposition technology“ OSD
Method "," S-DEC method ": Shin Metal Industry Co., Ltd .: Spring 1999 issue, the conventional example only considers that the temperature at the time of manufacturing the dispersion is equal to or higher than the melting temperature of the alkali metal. However, the influence of temperature is not taken into consideration from the viewpoint of improving the production efficiency of the dispersion.

However, the surface tension of the alkali metal and the viscosity coefficient of the dispersion liquid are strongly affected by temperature. In an alkali metal, the higher its temperature is above its melting point,
The surface tension decreases. When a hydrocarbon compound or a silicon compound having a small molecular weight is used as the dispersion liquid, the higher the temperature reaches the boiling point, the lower the viscosity coefficient. Further, when a thermosetting compound is used as the dispersion liquid, the higher the temperature, the higher the viscosity coefficient. In the conventional example, since the dispersion is manufactured in the vicinity of the melting point of the alkali metal, the condition that the surface tension of the alkali metal and the viscosity coefficient of the dispersion liquid are large, that is, the size of the dispersion is large (coarse) and the manufacturing efficiency is poor. It means that they are manufactured under the conditions.

In the present invention, in order to produce a dispersion with smaller dimensions (finer) and good production efficiency, when a hydrocarbon compound or silicon compound having a small molecular weight is used as the dispersion liquid, the boiling point is the upper limit. As a higher temperature, when a thermosetting compound is used in the dispersion liquid, the temperature during dispersion production is controlled so as to be maintained at a temperature near the midpoint between the boiling point and the melting point of the alkali metal. .

The temperature control method of the cooling and heating device adopted in the present invention will be described below with reference to FIG. Cooling and heating device 1
5 is controlled as follows. When the temperature measured by the thermometer 16 reaches the heater upper limit temperature preset in the cooling / heating device 15, the output of the heater incorporated in the cooling / heating device 15 is reduced or the power supply itself is turned off. Thermometer 1
When the temperature measured in 6 reaches the heater set temperature lower limit preset in the cooling / heating device 15, the output of the heater is increased or the power source itself is turned on.

On the other hand, when the temperature measured by the thermometer 16 reaches the preset upper limit of the cooler set temperature of the cooling / heating device 15, the output of the cooler incorporated in the cooling / heating device 15 is increased or the power source itself. Is thrown in. When the temperature measured by the thermometer 16 reaches the cooler set temperature lower limit preset in the cooling / heating device 15, the output of the cooler is reduced or the power supply itself is turned off. The other cooling / heating devices 27, 37, 47 and 67 described in this embodiment also have the same heating / cooling temperature control function as the cooling / heating device 15.

The following are typical as a cooler and a heater constituting the cooling / heating device 15. The cooler is an indirect method in which heat is exchanged between an object to be cooled (liquid in the container in this embodiment) and the outside of the cooler via a fluid sealed inside the cooler, or a room temperature atmosphere in which the device is placed. Any of the direct methods of introducing heat and exchanging heat with the object to be cooled may be adopted. On the other hand, the heater is an indirect type in which heat is exchanged between the object to be heated (the liquid inside the container in this embodiment) and the outside of the heater via a fluid sealed in the heater, or a heating source such as a heater. Any of the direct methods of exchanging heat between the heating target and the object to be heated may be adopted.

In this embodiment, as a temperature control method for the cooling and heating apparatus, a control thermometer is installed near the portion (heat exchanger: the wavy line portion in the figure) immersed in the liquid inside the container.
If the thermal conductivity of the container is good, a thermometer may be installed inside and outside the inner wall of the container.If the thermal conductivity of the dispersion liquid is good, a thermometer may be installed at the container inlet / outlet in contact with this liquid. May be. Further, in this embodiment, the temperature of the dispersion in the container is automatically controlled by using the temperature measured by the thermometer, but this temperature control is manually performed only by a temperature indicator instead of the regulator. It is also possible to have a device configuration that is implemented in 1.

In this embodiment, the alkali metal 35 and the dispersion liquid 25 sent to the dispersion manufacturing apparatus are stored in the storage containers 3 on the upstream side of the alkali metal dispersion manufacturing container 1.
The temperature is controlled by using the cooling and heating devices 37 and 27 attached to 1 and 21. In this way, by controlling the temperatures of the alkali metal 35 and the dispersion liquid 25 in advance of dispersion manufacturing, it becomes possible to more easily control the temperature in the manufacturing apparatus and improve the dispersion manufacturing efficiency. Also,
Since the temperature of the alkali metal or the dispersion liquid is adjusted in advance on the upstream side, it is easy to add it to the dispersion production container during production or to deliver the produced dispersion according to this additional amount. is there. However, the cooling and heating devices 37 and 27 may not be attached to each of the storage containers 31 and 21.

In the production of the alkali metal dispersion in this embodiment, the temperature of the production material is set within a predetermined temperature range by using a cooling and heating device attached to the container, from the melting point of the alkali metal to the boiling point of the dispersion liquid. Controlling within the temperature range is a key point of the present invention. As an example thereof, the case of producing a sodium-liquid paraffin dispersion will be taken. Liquid paraffin is liquid at room temperature and has a boiling point of 300 ° C.
As described above, the temperature change of the viscosity coefficient is small. On the other hand, sodium has a melting point of 98 ° C and a boiling point of 883 ° C under atmospheric pressure. The surface tension of sodium is 194 mN at a temperature of about 130 ° C.
/ M, 184 mN / m at about 230 ° C, 17 at about 330 ° C
The surface tension is 4 mN / m, and the surface tension decreases as the temperature increases. From the above, the predetermined temperature range is 98 to 3
It becomes 00 ° C.

Within this temperature range, the surface tension of sodium is 11% smaller at 330 ° C. than at 130 ° C. Therefore, in the case of producing a sodium-liquid paraffin dispersion, the case of controlling at a higher temperature than the case of controlling at a temperature of 100 ° C. or higher in the vicinity thereof disperses more efficiently from the viewpoint of the dispersion generation condition described above. The body can be manufactured. In this case, if it is possible to control the temperature in the vicinity of 300 ° C. or less by the equipment capacity, the dispersion manufacturing efficiency becomes optimum when manufacturing under this temperature condition.

In this example, the treatment of the hardly decomposable halogen compound was taken as the target of the dehalogenation treatment, but the present example is not limited to this, and instead of the hardly decomposable halogen compound, it reacts with an alkali metal. Any substance (regardless of gas, liquid, and solid) may be used, and the dispersion can be used as a reducing agent, an adsorbent of such a substance, or a processing decomposition agent thereof.

When a substance or compound (eg, water or alcohols) which reacts with an alkali metal to generate hydrogen is used instead of the hardly decomposable halogen compound, it is compared with the case of mixing with a single alkali metal. Then, the reaction is mild, and the dispersion can be used as a safe hydrogen generating agent. For example, 3 mL of water in 10 mL of sodium-liquid paraffin dispersion (mass concentration of sodium 11%)
It was confirmed that when hydrogen peroxide was injected into the atmosphere, hydrogen bubbles continued to be generated for several minutes without ignition and the sodium-water reaction proceeded gently.

(Second Embodiment) FIG. 6 shows a second embodiment of the present invention. The second embodiment is a modification of the first embodiment, and is the same as the first embodiment except for the changes described below.

In FIG. 1, an alkali metal dispersion manufacturing container 1 is shown.
The state of the alkali metal sent to is not particularly limited. On the other hand, in FIG. 6 of the present embodiment, a spray nozzle 7 is attached to the tip of the alkali metal dispersion production container 1a of the alkali metal delivery pipe, and when the alkali metal is delivered from this, droplets having a small diameter are previously prepared. Separate into 8 and mix with the dispersion liquid 5a. A pump 6 is attached to the delivery pipe in order to increase the delivery pressure from the spray nozzle 7. Then, the ultrasonic waves emitted from the ultrasonic dispersion device 10a attached to the alkali metal dispersion manufacturing container 1a are dispersed into the alkali metal droplets 8 in a smaller amount.

As described above, when the alkali metal is separated into the small droplets 8 in advance, the contact area between the alkali metal and the dispersion liquid is expanded, and the frictional force at the contact interface is further increased. , Ultrasonic dispersion device 10
The efficiency of producing the alkali metal dispersion 5a using a is significantly improved. For example, in a test in which a sodium-liquid paraffin dispersion was manufactured, it was confirmed that when sodium was divided into droplets 8 having a size of 1 cm or less, dispersion by ultrasonic waves was more likely to proceed.

Although the alkali metal dimension adjusting method using the spray nozzle 7 is adopted in this embodiment, the adjusting method is not limited to the spray nozzle 7, and the spray nozzle 7 may be used.
Instead of this, other pressure difference delivery type disperser (for example, orifice, injector, etc.) may be used. When such a pressure difference delivery type disperser is used, a pressure source (the pump 6 in this embodiment) is required, but an effect of injecting an alkali metal by the pressure difference to stir the entire dispersion is also obtained. .

When the above-mentioned pressure difference delivery type disperser including the spray nozzle 7 is used, if the size of the alkali metal to be dispersed is uniform and on the order of 1 to 10 μm, it is not necessary to install the ultrasonic type dispersion device 10a. Absent.

In this embodiment, a dehalogenation treatment container 61a for a hardly decomposable halogen compound, a cooling and heating device 67a for adjusting the temperature of a mixed liquid 65a of an alkali metal dispersion and a hardly decomposable halogen compound, An ultrasonic dispersion device 69 is attached as a stirring means instead of the stirrer for promoting the reaction of the mixed liquid shown in FIG. A function of preventing the metal fine particles in the alkali metal dispersion injected into the dehalogenation treatment container 61a from aggregating or settling, in addition to exhibiting the stirring action of the ultrasonic dispersion device 69 and the mixed liquid 65a. Also has. Furthermore, since the ultrasonic waves emitted from the ultrasonic dispersion device 69 have the effect of promoting the chemical reaction, compared with the case where the stirrer of the first embodiment is used,
The dehalogenation treatment of the hardly decomposable halogen compound can be performed more simply and more efficiently.

When the stirrer of the first embodiment is adopted, the stirrer is made up of large parts such as a stirring motor and blades, so that the processing apparatus is large. On the other hand, in the processing device having the ultrasonic dispersion device 69 attached thereto, the ultrasonic dispersion device 69 does not include a simple and large dynamic device such as a high frequency power source and an ultrasonic generator, and thus the device itself is not included. Can be miniaturized.

(Third Embodiment) FIG. 7 shows a third embodiment of the present invention. The third embodiment is a modification of the second embodiment, and is the same as the second embodiment except for the changes described below.

In the above-mentioned second embodiment, the dehalogenation treatment container is provided with an ultrasonic dispersion device. In this embodiment, the persistent halogen compound is received in the dehalogenation treatment container 61b via the delivery pipe 62b. On the other hand, the alkali metal dispersion 5b is manufactured by the alkali metal dispersion manufacturing container 1b and the ultrasonic dispersion device 10b, and the manufactured alkali metal dispersion 5b is injected into the dehalogenation treatment container 61b via the pipe 4b. A circulation channel is formed. In the dehalogenation treatment container 61b, the mixed liquid 65b
Also provided are cooling and heating devices 67b and 65b for adjusting the temperature of the tank, and a pipe 63b and a pump 68b for delivering the contents in the dehalogenation treatment container 61b after the dehalogenation treatment to the separator.

By the injection described above, a mixed liquid 65b of the alkali metal dispersion 5b and the hardly decomposable halogen compound is formed in the dehalogenation treatment container 61b. The mixture
65b circulates in and out of the dehalogenation treatment container 61b via a circulation pipe 91 attached to the dehalogenation treatment container 61b, an ultrasonic dispersion device 92, and a circulation pump 93. The circulation is performed by the pumping action of the circulation pump 93, and the mixed liquid 65b receives the ultrasonic waves emitted from the ultrasonic dispersion device 92 during the circulation to accelerate the dehalogenation treatment in the mixed liquid 65b.

In this embodiment, the dehalogenation treatment container 61 is used.
Since a circulation flow path composed of a pipe 91, an ultrasonic dispersion device 92, and a pump 93 is attached to b, the dehalogenation treatment container 61b itself is provided with an ultrasonic dispersion device.
In addition to the function of the ultrasonic dispersion device described above in the embodiment, the pump 93 also has a stirring function.

As described above, in any of the examples, the alkali metal dispersion can be produced industrially simply and efficiently with a small and simple apparatus. Further, compared with the conventional method, not only a homogeneous and fine particle alkali metal dispersion can be obtained, but also the production efficiency can be greatly improved, which is an economically advantageous method. The application scene of can be expanded.

Further, by using the alkali metal dispersion as the dehalogenation treating agent, the dehalogenation treatment of the hardly decomposable halogen compound can be easily carried out.

[0067]

According to the method for producing an alkali metal dispersion of the present invention, an alkali metal dispersion can be produced efficiently. Further, according to the dehalogenation treatment method of the hardly decomposable halogen compound according to the present invention, since the alkali metal dispersion of homogeneous and fine particles can be used as the dehalogenation treatment agent, the hardly decomposable halogen compound can be efficiently treated. Can be well dehalogenated.

[Brief description of drawings]

FIG. 1 is a piping system diagram relating to an apparatus for producing an alkali metal dispersion and a dehalogenation treatment apparatus for a persistent halogen compound according to a first embodiment of the present invention.

FIG. 2 is a flow chart showing a production procedure of an alkali metal dispersion and a dehalogenation treatment procedure of a hardly decomposable halogen compound according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a change in surface tension of an alkali metal with respect to temperature and a change in viscosity coefficient with respect to temperature in an example of a dispersion liquid according to a first embodiment of the present invention.

FIG. 4 is a diagram showing a change in surface tension of an alkali metal with respect to temperature and a change in viscosity coefficient with respect to temperature in another example of a dispersion liquid according to the first embodiment of the present invention.

FIG. 5 is an operation sequence diagram of the heating / cooling device for temperature adjustment used in the first embodiment of the present invention.

FIG. 6 is a piping system diagram relating to an apparatus for producing an alkali metal dispersion and a dehalogenation treatment apparatus for a persistent halogen compound according to a second embodiment of the present invention.

FIG. 7 is a piping system diagram relating to an apparatus for producing an alkali metal dispersion and a dehalogenation treatment apparatus for a persistent halogen compound according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Alkali metal dispersion manufacturing container, 2 ... Alkali metal delivery piping, 3 ... Dispersion liquid introduction piping, 4 ... Alkali metal dispersion delivery piping, 5 ... Alkali metal dispersion, 10 ... Ultrasonic dispersing device, 11 ... Ultrasonic generator, 12 ... High frequency power source, 15 ... Cooling / heating device, 16 ... Thermometer, 17 ... Temperature conversion indicator, 18 ... Cooling / heating device control line, 21 ... Dispersion liquid storage container, 31 ... Alkali metal storage container , 41 ... Persistent halogen compound storage container, 51 ... Substitution device, 61 ...
Persistent halogen compound dehalogenation treatment container, 66 ...
Stirrer, 67 ... Cooling / heating device in decomposable halogen compound dehalogenation treatment apparatus, 68 ... Pump, 70 ... Separator, 71 ... Storage container for refractory halogen compound dehalogenation treatment liquid, 81 ... Another difficulty Storage container for dehalogenating treatment liquid for degradable halogen compounds.

Continued front page    F-term (reference) 4H006 AA05 AC13 AC26 BA02 BA91                       BB48                 4K017 AA08 BA10

Claims (2)

[Claims] 1. A method for producing an alkali metal dispersion by dispersing an alkali metal in a liquid that does not react with an alkali metal, wherein the liquid containing the alkali metal is in a temperature range from a melting point of the alkali metal to a boiling point of the liquid. A method for producing an alkali metal dispersion, which comprises heating the liquid to the temperature range and applying ultrasonic waves to the liquid and the alkali metal to disperse the alkali metal in the liquid to form an alkali metal dispersion. 2. A hardly decomposable halogen compound for removing a halogen from the hardly decomposable halogen compound by bringing the hardly decomposable halogen compound into contact with the alkali metal dispersion produced by the production method according to claim 1. Dehalogenation treatment method.