JP2000160382A - Electrolytic fluorination device for organic compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably perform the electrolytic fluorination of an organic compound for a long period in a high yield by alternately placing plural cathode plates and plural anode plates at intervals of a certain distance, placing a cathode current collecting plate and an anode current collecting plate opposite to each other while interposing the arrangement of these cathode plates and anode plates between the both current collecting plates and connecting one side edge of each of the cathode plates and one side edge of each of the anode plates to the cathode current collecting plate and the anode current collecting plate, respectively, throughout the entire length of each of the side edges. SOLUTION: This device is provided with: an electrolytic cell 8 having a supply port 5 for supplying a solution to be electrolyzed, in the lower part, and an electrolyzed solution withdrawal port 6 and a gas withdrawal port 7, in the upper part; plural cathode plates 1 and plural anode plates 2, which are alternately placed at intervals of a certain distance in the electrolytic cell 8; a cathode current collecting plate 3 and an anode current collecting plate 4, which are placed oppositely to each other while interposing the arrangement of the cathode plates 1 and anode plates 2 between the both current collecting plates 3 and 4, wherein one side edge of each of the cathode plates 1 and one side edge of each of the anode plates 2 are connected and fixed to the cathode current collecting plate 3 and the anode current collecting plate 4, respectively, throughout the entire length of each of the side edges, and also, each of the electrode current collecting plate 3 and 4 is fitted to a shell of the electrolytic cell 8 through a heat insulator consisting of an insulating member; a cathode rib 10 and an anode rib 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrolytic fluorination method for electrochemically fluorinating an organic compound between an anode and a cathode in an electrolytic bath solution. More specifically, the present invention relates to a novel electrolytic fluorination apparatus capable of extremely efficiently and stably performing electrolytic fluorination of organic substances, and a method for producing a fluorinated organic compound using the electrolytic fluorination apparatus.

[0002]

2. Description of the Related Art The electrolytic fluorination method is well known as a method for fluorinating organic compounds. The obtained fluorinated organic compound is widely used as an inert liquid, a surfactant raw material, a medical and agricultural chemical precursor, and the like.

In carrying out the above electrolytic fluorination method industrially, various problems have been pointed out. For example, because the yield of electrolytic fluorinated organic compounds such as perfluoro compounds of interest is low, a polymer substance is generated during electrolysis and electrolysis cannot be stably continued for a long time, or electrolysis cannot be performed at a high current density. There were problems such as the increase in equipment for the production volume.

In order to solve these problems, Japanese Patent Publication No. 30399/1988 proposes a method of adding a sulfur compound such as dimethyl sulfoxide. Also, Japanese Patent Application Laid-Open No. 1-28397 proposes a method in which a mixture of one having a relatively large number of carbon atoms and one having a relatively small number of carbon atoms is used as a raw material in electrolytic fluorination of trialkylamine.

[0005] Although these methods have some effects, they have not been able to sufficiently solve the above-mentioned problems.

As an electrolytic fluorination apparatus for performing electrolytic fluorination, Japanese Patent Publication No. Sho 31-3660, Fluorin Chemistry, Vol. 1, p. 418 (edited by Simmons, 195)
0), JP 47-18775, JP 4-14
A so-called Simmons-type electrolytic cell disclosed in 3288 and the like has been conventionally used. For example, the structure of the electrolytic cell illustrated in FIG. 3 is a typical example. This electrolyzer is
In the structure of the electrode portion configured by alternately arranging the plurality of anode plates 2 and the cathode plates 1, the anode plate and the cathode plate are provided at one point where they do not overlap with each other.
It is generally connected to the rod-shaped anode ribs 11 and cathode ribs 10 through the respective members, and each rib is taken out from the upper part of the battery case lid.

However, when electrofluorination is carried out using this electrolytic cell, particularly on an industrial scale, the dissolution of the anode plate occurs unevenly, and as the electrolysis is continued, the distance between the electrodes facing each other is partially increased. There is a difference. When the dissolution of the anode plate occurs unevenly, a part of the anode plate is extremely melted, so that there is also a problem that the replacement life of the anode is short.

Thus, the conventional electrolytic fluorination apparatus is
In addition to being insufficient for solving the above problems, it also has the various problems described above.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electrolytic fluorination apparatus which can be operated at a stable electrolysis voltage for a long period of time even when electrolysis is performed at a high current density and can be obtained in a high yield. And an electrolytic fluorination method using the electrolytic fluorination apparatus.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, the phenomenon that the dissolution of the anode plate occurs unevenly is caused by the method of connecting the current collector to the electrode plate. I found it. That is, the connection between the electrode plate and the current collector in the conventional electrolytic fluorination apparatus is generally connected to the current collector at one point (generally, several cm wide) of the electrode plate as shown in FIG. It has been found that this connection mode greatly affects the above phenomenon.

[0011] This is a phenomenon that cannot be predicted from the high conductivity of the electrode plate, and is a surprising phenomenon that occurs remarkably in a special environment of electrolytic fluorination of an organic compound.

Further, as a result of further study, the current collector was made into a plate shape, and the electrode plate was connected to the current collector plate whose side sides corresponded to the current collector plate over the entire length, so that the amount of dissolution of the anode plate was increased. Can be made uniform over substantially the entire surface, and an extremely high productivity and stability can be achieved at the same time, and an electrolytic fluorination apparatus having a long equipment life has been successfully completed, and the present invention has been proposed.

That is, the present invention provides a plurality of cathode plates and anode plates alternately arranged at intervals, and a cathode current collector plate and an anode current collector provided opposite to each other with the arrangement of the cathode plates and anode plates interposed therebetween. An electrolytic fluorination apparatus for an organic compound, comprising: an electrolytic cell having an electrode portion formed of an electric plate, and the sides of the cathode plate and the anode plate are respectively connected to the corresponding current collector plates over the entire length. is there.

The present invention also relates to a method of supplying an electrolytic solution comprising a hydrogen fluoride solution containing an organic compound to a supply port of the electrolytic fluorination apparatus and performing electrolytic fluorination at a current density of 3 to 50 dm 2 / A. There is also provided a method for producing the characterized fluorinated organic compound.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The electrolytic fluorination apparatus of the present invention will be described below with reference to the accompanying drawings, but the present invention is not limited to these accompanying drawings.

FIG. 1 is a side view showing a typical embodiment of the electrolytic fluorination apparatus of the present invention, and is a sectional view showing the periphery of an electrode section.

In the present invention, the electrolytic fluorination apparatus accommodates an electrode portion A in an electrolytic cell 8 and has a supply port 5 for an electrolytic solution made of an anhydrous hydrogen fluoride solution containing an organic compound below the electrode portion A. Has an electrolyte solution outlet 6 and a gas outlet 7 above the electrode portion A.

As the material of the cell portion of the electrolytic cell, those having corrosion resistance under the use environment are used without any particular limitation, and for example, iron, stainless steel, nickel, nickel alloy, tetrafluoroethylene resin and the like can be used.

In the electrolytic fluorination apparatus of the present invention, a plurality of cathode plates 1 and anode plates 2 in which electrode portions A are alternately arranged at intervals, and a pair of cathode plates 1 and anode plates 2 opposed to each other with the arrangement of the cathode plates 1 and anode plates 2 interposed therebetween. A cathode current collector plate 3 and an anode current collector plate 4 provided as
It is characterized in that the sides of the cathode plate 1 and the anode plate 2 are connected to the corresponding current collector plates 3 and 4 over the entire length.

As described above, in the conventional structure of the electrode portion of the electrolytic fluorination apparatus, the electrode plate is connected to the current collector at one point, and one side of the electrode plate extends over the entire length as in the present invention. Not connected to current collector. Therefore, in the conventional electrolytic fluorination apparatus using the electrode unit,
A phenomenon in which the dissolution of the anode plate occurs unevenly occurs, causing the various problems described above, and reducing the productivity.

On the other hand, according to the present invention, the current collectors are plate-shaped current collectors 3 and 4, and the current collectors are provided with electrode plates over the entire length of the current collectors corresponding to the sides. By connecting, the dissolution amount of the anode plate can be made substantially uniform over substantially the entire surface, so that the gap between the anode plates is always kept almost constant over the entire surface, even if the anode plate is melted and the gap is enlarged. However, it is possible to maintain high productivity without decomposing an organic compound due to a local increase in current density. Further, since the entire anode plate is uniformly dissolved, it can be used without any problem even in an extremely thin state, and the replacement life of the anode plate can be significantly improved.

Therefore, in the electrolytic fluorination of an organic compound, it is possible to realize an extremely high productivity and stability while realizing an electrolytic fluorination apparatus having a long life.

In the present invention, the side surfaces of the cathode plate 1 and the anode plate 2 are connected to the corresponding current collector plates 3 and 4 over the entire length, respectively, as shown in FIG. In general, the connection is made continuously, but an intermittent connection can be adopted by providing the non-connection portions at intervals. Such embodiments are, in particular,
It is preferable that the electrode plate is attached to the current collector plate by welding because the non-connection portion serves to alleviate the stress applied to the welded portion of the electrode plate and can effectively prevent the electrode plate from warping.

In the aspect in which the side faces of the electrode plate are intermittently connected, the length of the non-connection portion is appropriately determined within a range that does not significantly impair the effects of the present invention. Such a length is desirably 50% or less, preferably 30% or less, with respect to the side length of the electrode plate. Further, the length of one non-connection portion is preferably 50 mm or less, particularly preferably 30 mm or less.

The material, size, number of sheets and the like of the above-mentioned cathode plate and anode plate are not particularly limited. Examples of the material of the cathode include iron, copper, nickel, nickel alloy, iron alloy and the like. For example, nickel, a nickel alloy or the like is preferable. In particular, as a material of the anode, the concentration of iron contained as an impurity is 1,000 ppm or less, preferably 40 ppm or less.
The use of nickel of 0 ppm or less is advantageous because it has the effect of allowing stable operation to be continued for a long period of time even under high electrical tightness.

The effect of the electrolytic fluorination apparatus of the present invention becomes more pronounced as the size of the apparatus is increased. In particular, the surface area of the cathode plate and the anode plate used for electrolysis is 0.5 m2 or more, generally 1 to 200 m2. The present invention is suitable for the electrolytic fluorination apparatus.

The number of cathode plates and anode plates used is as follows:
Taking into account the operating conditions such as the electrolytic voltage,
About 50 sheets are suitable. The size of each of the cathode plate and the anode plate is such that the side length H, which is the connection portion with the current collector plate, is 50.
The side length W is preferably 0.3 to 1.0 times the side length H, particularly 0.5 to 150 cm.
0.8 times is preferable in order to prevent uneven dissolution of the anode.

Further, the distance between the cathode plate and the anode plate facing each other is not particularly limited, and a known setting condition may be adopted without any particular limitation, but usually 0.5 to 10 mm, preferably 1 to 5 mm is suitably adopted. You. That is, if the distance between the electrodes is larger than the above range, not only does the liquid resistance increase, but also the drift of hydrogen generated at the cathode and the supply of the electrolyte to be supplied from below the electrode portion increase the distance between the electrodes. It is difficult to keep the liquid flow rate high enough, and the fluorinated organic compound having a relatively high specific gravity, which is a product, tends to stay between the electrodes. If the generated fluorinated organic compound stays between the electrodes, it may cause decomposition or polymerization due to electrolysis, which is not desirable. Further, the distance between the electrodes may be smaller than the above range, but the manufacturing accuracy becomes difficult.

Further, in order to prevent contact between the anode plate and the cathode plate, an electrically insulating spacer may be attached to each electrode plate. The material, shape, mounting position, number of mounting, or mounting method of the spacer is not particularly limited because it depends on the size of the electrode plate. For example, a disc-shaped, plate-shaped or rod-shaped electric The insulator may be attached to the tip of the electrode plate or any other location by making holes in two to twenty places, inserting it into the electrode plate, or directly inserting it between the electrodes. Of course, since the spacer portion shields the electrode surface and reduces the effective surface area of the electrode plate, it is desirable that the spacer area is small, usually 5% or less, particularly 2% of the electrode area.
It is preferable to set the following.

In the present invention, the size of the current collectors 3 and 4 of the electrodes may be appropriately determined according to the size and the number of the electrode plates, and the material of the current collectors is the material of each electrode plate. May be appropriately determined in accordance with. Further, the current collector plate may be provided with ribs 10 and 11 as terminals for connection to a power supply at one or a plurality of divided portions.

In another preferred embodiment of the electrolytic fluorination apparatus of the present invention, an electrolytic fluorinating apparatus is provided in which a liquid to be electrolyzed is supplied from a lower part of an electrolytic cell, and the electrolytic liquid is taken out from an upper part through an electrode part. An apparatus is illustrated. That is,
The electrolytic cell is an electrolytic fluorination apparatus having a supply port for an electrolyte to be formed of a hydrogen fluoride solution containing an organic compound below an electrode portion, and an electrolyte solution outlet and a gas outlet above the electrode portion. is there.

The electrolytic fluorination apparatus in this case will be described with reference to FIG. 1 described above. An electrode portion A is accommodated in an electrolytic cell 8 and an anhydrous hydrogen fluoride solution containing an organic compound is placed below the electrode portion A. In this embodiment, the supply port 5 for the electrolytic solution has an outlet 6 for the electrolytic solution and a gas outlet 7 above the electrode portion A. Further, the mounting position of the supply port 5 for the electrolytic solution is not particularly limited as long as it is below the electrode portion A. The electrolytic solution outlet 6 and the gas outlet 7 are not particularly limited as long as they are above the electrode portion A. Generally, the gas outlet 7 is provided above the electrolytic solution outlet 6.

Although the generated fluorinated organic compound can be decomposed by electrolysis when it stays between the electrodes, the above configuration of the electrolytic fluorination apparatus allows the generated fluorinated organic compound to be converted into a drift of hydrogen gas generated at the cathode. The effect and the ascending flow due to the supply of the liquid to be electrolyzed from the lower part of the electrolytic cell raises the space between the electrodes, so that it can be efficiently taken out together with the anhydrous hydrogen fluoride solution from the solution electrolyte outlet 6.

Further, as one of the preferable embodiments in this case, the mounting position of the electrolyte solution outlet 6 is set to a height L (m) from the upper end of the electrode portion to the center of the electrolyte solution outlet.
m) is determined so as to satisfy the following relationship with the height H (mm) of the electrode portion.

0.2H ≦ L ≦ 0.8H That is, by adjusting the mounting position of the electrolytic solution outlet 6 within this range, the electrolyte solution passed through the electrode portion to reach the upper portion thereof. The fluorinated organic compound can be more efficiently taken out at a high concentration before settling due to the difference in specific gravity of the liquid, and the fluorinated organic compound can be prevented from accumulating on the upper portion of the electrode portion.

In another preferred embodiment, a baffle plate 9 is provided on a wall surface of the electrolytic cell between the supply port 5 for the liquid to be electrolyzed and the electrode section so that the liquid to be electrolyzed is biased to the effective energizing section of the electrode section. Is mentioned.

That is, the electrolytic fluorination apparatus of the present invention comprises:
Since the cathode plate and the anode plate are attached with one side connected to the current collector, a slight gap is required between the tip of the electrode plate and the current collector of the opposite polarity. Then, substantially no electrolysis reaction occurs in the gap. In the above aspect, the supply of the electrolytic solution to the gap is cut off, and the electrolytic solution is selectively supplied to an effective current-carrying portion effective for electrolysis of the electrode portion, so that the electrolytic solution can be produced with extremely high productivity. A fluorination reaction can be performed.

Therefore, the width of the baffle plate 9 may be appropriately determined according to the distance between the end of the electrode plate and the current collector plate of the opposite polarity. This width depends on the size of the electrode plate, but is generally 5 to 100 mm, preferably 10 to 50 mm.

The material of the baffle is not particularly limited.
The same material as the battery case main body or a fluorine-based resin such as ethylene tetrafluoride is generally used.

Another preferred embodiment is one in which at least the body of the electrolytic cell is covered with a heat insulator made of an insulating member.

That is, since the electrolyte to be treated according to the present invention handles hydrogen fluoride in a liquid state, the electrolyte to be treated and the electrolyte containing the fluorinated organic compound produced by electrolytic fluorination are kept at a temperature lower than the boiling point. Is particularly preferred. For this reason, the temperature control system described later is generally adopted. However, it is possible to cover the outside of the body of the electrolytic cell, that is, the portion where the hydrogen fluoride solution is present in the electrolytic cell, with a heat insulator made of an insulating member. This is effective for increasing the cooling effect of the system.

As the heat insulator, an insulator made of an insulating material is used to prevent a leakage current or short circuit outside the electrolytic cell. For example, materials such as glass wool and foamed polyurethane are preferable.

In still another preferred embodiment,
In order to evenly supply the liquid to be electrolyzed between the electrodes of the electrode section, an embodiment in which a rectifying plate 12 made of a plate-like body having many uniform holes below the electrode section is provided.

As the rectifying plate, a rectifying plate having a certain rectifying function and an aperture ratio of about 3 to 30% is used without any particular limitation. For example, a grid-like plate such as an expanded plate, a perforated plate,
One or a combination of a plurality of wire meshes may be used.

In the present invention, as the temperature control mechanism in the electrolytic cell, a known structure and system are employed without any particular limitation.
For example, a system for adjusting the temperature while cooling the electrolyte to be supplied to the electrolytic cell by a cooling means such as a heat exchanger provided outside, and a system for adjusting the temperature by incorporating a cooling device in the electrolytic cell are common. It is.

Further, although FIG. 1 shows an embodiment in which the current collectors 3 and 4 are built in the electrolytic cell main body, an embodiment in which the side walls of the electrolytic cell are constituted by the current collectors is also possible.
By adopting such an embodiment, it is possible to provide an electrolytic fluorination apparatus in which the operation of attaching and detaching the electrode to and from the electrolytic cell is extremely simplified.

The most preferred embodiment of the electrolytic fluorination apparatus of the present invention is shown in FIG. That is, the electrolytic fluorination apparatus shown in FIG. 2 is configured such that a cathode plate 1 and an anode plate 2 arranged at an interval are connected to a cathode current collector plate 3 and an anode current collector plate 4 on the sides, respectively. A unit 13 and an anode unit 14, a frame 15 having a supply port 5 for the solution to be electrolyzed, an outlet 6 for the electrolyte, and a gas outlet 7, and having opposing walls opened. A unit 14 is arranged opposite to the cathode plate 1 and the anode plate 2 in the opening of the frame 15 so that the cathode plate 1 and the anode plate 2 are arranged at an interval from each other. An embodiment is shown in which an electrolytic cell is formed by pressing the anode current collector plate 4 and the anode current collector plate 4 through an insulating packing (not shown).

The cathode rib 10, the anode rib 11, the baffle plate 9 and the rectifying plate 12 can be provided as needed.

In the embodiment shown in FIG. 2, the insulation between the frame 15 and the cathode unit 13 and the anode unit 14 is generally performed by providing an insulating packing between the surfaces which are pressed against each other. However, the insulating packing is 10 to 200 mm, preferably 20 mm outside the pressure contact part.
It is preferable to provide the extension by about 100 mm.

That is, the electrolytic fluorination method using the electrolytic fluorination apparatus of the present invention is particularly preferably carried out at a temperature lower than the boiling point of hydrogen fluoride having a boiling point of 19 ° C. in order to maintain the liquid state. For this reason, dew condensation can occur on the outer wall surface of the electrolytic cell constituting the electrolytic fluorination apparatus, and particularly when the packing layer is covered with an aqueous layer, a leakage current is likely to occur. Further, in some cases, there is a possibility that the situation may develop to a short circuit.

In the above aspect of the present invention, by providing the packing extending in the form of a flange around the pressure contact portion, the leakage current, and furthermore, the short circuit due to the leakage of the electrolytic solution or the water droplet is extremely effective. Can be prevented.

Further, when a large number of electrolytic fluorination apparatuses of the present invention are installed, it is particularly preferable to connect a large number of electrolytic cells in series with one rectifier from the viewpoint of energy saving of electric power. In this case, the anode of one electrolytic cell and the cathode of another electrolytic cell may be joined by metal ribs. In the electrolytic fluorination apparatus according to the present invention, an aspect in which the current collector plate forms the side wall of the electrolytic cell. In the case of, the anode current collector of one electrolytic cell and the cathode current collector of another electrolytic cell can also be connected by crimping by a filter press method or the like,
By adopting such an embodiment, an extremely simplified electrolytic fluorination apparatus group can be employed.

By electrolytically fluorinating an organic compound using the electrolytic fluorination apparatus of the present invention, high productivity can be achieved.
And a fluorinated organic compound can be stably produced.

That is, the present invention provides a method of supplying an electrolytic solution comprising a hydrogen fluoride solution containing an organic compound from a supply port to the above electrolytic fluorination apparatus, and performing electrolytic fluorination at a current density of 3 to 50 A / dm2. There is also provided a method for producing the characterized fluorinated organic compound.

In the present invention, the organic compound to be subjected to electrolytic fluorination is not particularly limited.
An organic compound having a hydrogen atom directly bonded to a carbon atom,
And an organic compound having a carbon-carbon double bond can be used without any limitation. For example, hydrocarbons such as aliphatic saturated hydrocarbons, aliphatic unsaturated hydrocarbons, and aromatic hydrocarbons which have been known as the subject of electrolytic fluorination; linear or cyclic aliphatic primary amines, Amines such as amines or tertiary amines and aromatic amines; alkyl morpholine or morpholine derivatives; linear or cyclic ethers such as aliphatic ethers, aromatic ethers and polyethers;
Alcohols such as linear or cyclic aliphatic alcohols and aromatic alcohols; phenols; linear or cyclic aliphatic carboxylic acids, aromatic carboxylic acids and the like, and carboxylic acid chlorides and carboxylic acid fluorides derived therefrom. Carboxylic acid halides, or carboxylic acids such as acid anhydrides and esters and derivatives thereof; ketones; aldehydes; aliphatic sulfonic acids, aromatic sulfonic acids and sulfones such as sulfonic acid chlorides and sulfonic acid fluorides derived therefrom Sulfonic acids and derivatives thereof such as acid halides and esters; sulfur-containing compounds such as thiols and thioethers; and mixtures thereof.

Of these, considering the solubility in hydrogen fluoride used in electrolytic fluorination, nitrogen atoms and
Organic compounds having at least one of an oxygen atom and a sulfur atom are preferred. Of course, it goes without saying that an organic compound in which a hydrogen atom of the above organic compound is partially substituted by a halogen atom such as a fluorine atom can also be used as a raw material.

Among the above-mentioned organic compounds, those compounds in which the effect of the present invention is remarkable are organic compounds in which the total of each atom of ammonia and carbon, nitrogen, oxygen and sulfur is 1 to 40, and further 3 to 20. Organic compounds. Particularly, tertiary amines, ethers, thiols, carboxylic acids, sulfonic acids, and morpholines are preferably used.

In the present invention, the hydrogen fluoride used for electrolytic fluorination may be a commercially available hydrofluoric anhydride as it is, or if necessary, a known amount of water contained in a trace amount may be previously removed by electrolysis at a low current density. Used after removal by a method. If necessary, a third component such as a quaternary ammonium salt or a conductivity increasing agent may be added.

As a method of supplying the raw material hydrogen fluoride and the organic compound, a batch type and a continuous type can be appropriately adopted according to the structure of the electrolytic fluorination apparatus.
According to the method of the present invention, since the electrolytic fluorination can be stably performed over a long period of time, it is particularly preferable to perform the continuous fluorination.

In the present invention, the electrolysis temperature is usually -20 to
The temperature may be selected from a temperature range of 50 ° C, preferably 0 to 20 ° C. Further, it is particularly preferable that the temperature difference between the maximum liquid temperature and the minimum liquid temperature in the electrode portion is 10 ° C. or less, preferably 5 ° C. or less, because uneven dissolution of the anode based on the temperature difference battery can be prevented.

The method for adjusting the temperature is not particularly limited, but it is preferable to perform the operation by stirring or circulating the electrolytic solution, or by blowing an inert gas into the electrolytic solution. In particular, the above-mentioned electrolytic solution is supplied from the lower part of the electrolytic cell,
An embodiment in which the electrolytic solution is taken out from the upper portion through the electrode portion is more preferable. In this case, usually, the highest liquid temperature in the electrode section may be the liquid temperature at the electrolyte outlet, and the lowest liquid temperature in the electrode section may be the liquid temperature at the electrolyte supply port. Further, in this case, it is particularly preferable to set the liquid flow rate at which the electrode portion is raised to 3 cm / sec or more so that the generated fluorinated organic compound can be efficiently removed from the electrolytic cell.

In the present invention, the concentration of the organic compound in the electrolytic bath solution is from 10 to 50% by weight, and the electrolytic voltage is from 4 to 50% by weight.
What is necessary is just to select from 9V.

According to the present invention, it is possible to carry out electrolytic fluorination at an extremely high current density even on an industrial scale according to the present invention. However, if the current density is too high, the electrode ribs and equipment for heat removal must be large. 3 to 50 A / d
It is better to select from the range of m2, especially from the range of 7 to 30 A / dm2. The electrolysis pressure may be reduced or increased. However, it is preferable to perform the electrolysis at normal pressure in consideration of product recovery and incidental facilities.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

[0065]

EXAMPLE 1 A cathode unit 13 and an anode unit 1 in the form shown in FIG.
The cathode plate 1 and the anode plate 2 are opposed to each other so that the cathode plate 1 and the anode plate 2 are arranged at an interval in the opening of the frame 15, and the cathode current collector plate 3 and the anode An electrolytic fluorination apparatus in which the current collector plate 4 was pressed against each other via an insulating packing was used.

Each of the cathode plate 1 and the anode plate 2 has a size of a side of H860 mm, a side of W510 mm, and a thickness of 2 mm.
Of nickel plate (with an iron concentration of 100 ppm in the anode plate), 9 cathode plates and 10 anode plates were placed on each current collector plate at 50 mm sides with 10 mm sides.
Welded in width. Furthermore, 30 minutes from the tip of the anode plate
mm, 200mm from the position 30mm from the top
Five spacers made of ethylene tetrafluoride are attached at intervals by a rivet method by making a 10 mm hole in the anode plate. This spacer has an outer diameter of 15 mm and a thickness of 2 mm from the anode plate. Similarly, the cathode plate may be 30
mm, 200m from the position 130mm from the top
Four spacers made of ethylene tetrafluoride were attached at m intervals.

The cathode current collector 3 and the frame 15 (made of stainless steel), and the anode current collector 4 and the frame 15 were
5 was pressed against each other via a packing made of ethylene tetrafluoride that was 80 mm longer at each periphery. At this time, the distance between the poles of the anode plate and the cathode plate was 3 mm, and the distance between the tip of one electrode plate and the other electrode current collector plate, that is, the width of the opposite electrode portion without the electrode portion was 10 mm.

The frame 15 has an electrolyte supply port 5 below the electrode portion and an electrolyte solution outlet 6 above the electrode portion (the center portion is located at a height of 350 mm from the upper end of the electrode portion). A gas outlet 7 and a baffle plate 9 having a width of 20 mm and a rectifying plate 12 having an opening ratio of 10% (hole diameter 5 mm) are provided at the bottom. Further, the frame 15, the cathode unit 13 and the anode unit 1
4 were each independently covered with a 50-mm-thick foamed polyurethane heat insulating material.

Using this electrolytic fluorination apparatus, a circulating tank, a circulating pump, a cooler, and a condenser are arranged, and hydrogen fluoride and tributylamine (tributylamine concentration 15% by weight) are used as raw materials. A DC power supply was applied between the anode ribs 11 at a current density of 10 A / dm 2 to perform electrolytic fluorination. The raw material is continuously supplied to the circulation tank, and the electrolyte is supplied to the lower supply port of the electrolytic fluorination apparatus at a temperature of 5 ° C. through a cooler using a circulation pump, and the electrolyte is supplied from the upper outlet. It was withdrawn at a temperature of 9 ° C. and circulated to a circulation tank. The electrolytic solution was circulated so that the linear flow rate between the electrodes was 9 cm / s. Hydrogen gas containing hydrogen fluoride generated by the electrolysis was passed from the gas outlet to the condenser, and the reflux liquid was returned to the circulation tank. The obtained fluorinated product was continuously extracted from the bottom of the circulation tank.

Ten days after the start of electrolysis, the yield of perfluorotributylamine was 81%, and the electrolysis voltage was 5.9 V. After that, electrolysis was continued for three months, but the yield and electrolysis voltage were stable. Three months later, the electrolytic fluorination apparatus was opened, and the thickness of the anode plate was measured. The thickness was reduced to 0.1 ± 0.01 mm from the initial value, and was almost uniform regardless of the position.

Comparative Example 1 An electrolytic fluorination apparatus having substantially the same structure as in Example 1 except that the electrode plate mounting structure was changed as shown in FIG. 3 was used. Was implemented.

As a result, 10 days after the start of electrolysis, the yield of perfluorotributylamine was 68%, and the electrolysis voltage was 6.2 V. As a result of continuing electrolysis for 3 months, the yield decreased to 61% and the electrolysis voltage was 6.6 V
Rose.

After three months, the electrolytic fluorination apparatus was opened, and the thickness of the anode plate was measured. The thickness was reduced to 0.6 mm at the upper part of the anode plate and 0.2 mm at the lower part with respect to the initial values. I was

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a typical embodiment of the electrolytic fluorination apparatus of the present invention.

FIG. 2 is a perspective view showing another typical embodiment of the electrolytic fluorination apparatus of the present invention.

FIG. 3 is a perspective view showing a conventional electrolytic fluorination apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cathode plate 2 Anode plate 3 Cathode current collecting plate 4 Anode current collecting plate 5 Supply solution of electrolyte solution 6 Electrolyte outlet 7 Gas outlet 8 Electrolyzer 9 Baffle plate 10 Cathode rib 11 Anode rib 12 Rectifier plate 13 Cathode Unit 14 Anode unit 15 Frame 16 Spacer 17 Cathode current collector 18 Anode current collector

Continued on the front page (72) Inventor Masaki Yoshinaga 1-1, Mikage-cho, Tokuyama-shi, Yamaguchi Pref. (72) Inventor Tsuyoshi Ikeda 1-1, Mikage-cho, Tokuyama-shi, Yamaguchi F-term (Reference) 4K021 AA04 AB09 AC01 AC30 BA04 BB03 BB04

Claims (12)

[Claims] 1. A method comprising: a plurality of cathode plates and anode plates alternately arranged at intervals; and a cathode current collector plate and an anode current collector plate provided to face each other with the arrangement of the cathode plate and the anode plate interposed therebetween. An electrolytic fluorination apparatus for an organic compound, comprising: an electrolytic cell having an electrode portion in which the sides of the cathode plate and the anode plate are connected to the corresponding current collector plates over the entire length. 2. A method according to claim 1, further comprising: a supply port for an electrolytic solution made of a hydrogen fluoride solution containing an organic compound below the electrode section; and an electrolytic cell having an electrolytic solution outlet and a gas outlet above the electrode section. The electrolytic fluorination apparatus according to claim 1, wherein: 3. The height L (mm) of the electrolyte solution to the center of the outlet with respect to the upper end of the electrode portion is equal to the height H (m) of the electrode portion.
The electrolytic fluorination apparatus according to claim 2, wherein the following relationship is satisfied with respect to m). 0.2H ≦ L ≦ 0.8H 4. The electrolytic fluorination according to claim 1, wherein a baffle plate is provided on a wall surface between the supply port of the liquid to be electrolyzed and the electrode section in the electrolytic cell, so that the liquid to be electrolyzed is deflected to an effective energizing portion of the electrode section. apparatus. 5. The electrolytic fluorination apparatus according to claim 1, wherein at least a body of the electrolytic cell is covered with a heat insulator made of an insulating member. 6. The anode plate according to claim 1, wherein the concentration of iron contained is 1000.
2. The electrolytic fluorination apparatus according to claim 1, wherein the apparatus comprises less than ppm of nickel. 7. The electrolytic fluorination apparatus according to claim 1, wherein a current plate made of a plate having a large number of uniform holes is provided below the electrode portion. 8. A cathode unit and an anode unit formed by connecting a cathode plate and an anode plate arranged at an interval to a cathode current collector plate and an anode current collector plate, respectively, at a side thereof, and a supply port of a liquid to be electrolyzed. A frame having an electrolyte outlet and a gas outlet, and having opposed walls opened. The cathode unit and the anode unit are spaced apart from each other within the opening of the frame by the cathode plate and the anode plate. An electrolytic cell is formed by pressing the cathode current collector plate and the anode current collector plate at the periphery of the frame via insulating packings, respectively, so as to be arranged so as to be spaced apart from each other. The electrolytic fluorination apparatus according to claim 1, comprising: 9. The electrolytic fluorination apparatus according to claim 8, wherein the insulating packing is provided so as to extend outside the pressure contact portion. 10. An electrolytic fluorinating apparatus according to claim 1, wherein an electrolytic solution comprising an organic compound-containing hydrogen fluoride solution is supplied from a supply port, and electrolytic fluorination is performed at a current density of 3 to 50 dm2 / A. A method for producing a fluorinated organic compound, comprising: 11. The method for producing a fluorinated organic compound according to claim 10, wherein a temperature difference between a maximum liquid temperature and a minimum liquid temperature in the electrode portion is 10 ° C. or less. 12. The method for producing a fluorinated organic compound according to claim 11, wherein the liquid flow rate at which the electrode section is raised is 3 cm / sec or more.