JP2003232707A - Method and apparatus for extracting furfural in oil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an extracting method and an extracting apparatus for furfural that can individually extract furfural in oil with a simple operation even if there are a number of sample oils. <P>SOLUTION: Acetonitrile 90 is injected onto a sample insulating oil 80 (A), and a stirrer 13a in a magnetic stirrer is rotated at 750 rpm, thus mixing and stirring the insulating oil 80 and the acetonitrile 90 (B). In this agitation, furfural in the insulating oil 80 migrates to the side of the acetonitrile 90. When the mixed liquid after stirring is allowed to be still standing for one minute, the acetonitrile 90 and the insulating oil 80 are separated into two layers (C). The separation may not be complete. When oil drips 80a adhering to the inner wall surface of a container body 3 floating in the acetonitrile 90 rotates the stirrer 13a at 250 rpm to generate an eddy current to the extent so that it does not reach agitation, the oil drips become a composite at the center of the eddy current (D). After the eddy current is extinguished (E), an injection needle 43 is inserted to sample the acetonitrile 90 (F). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method and an apparatus for extracting furfural in oil for extracting furfural contained in oil.

[0002]

2. Description of the Related Art Furfurals in insulating oil have been conventionally detected in order to diagnose the life of oil-filled electrical equipment such as oil-filled transformers and oil-filled reactors. That is, the life of these oil-filled electrical devices is generally estimated by the degree of deterioration of the insulating paper. And the deterioration degree of this insulating paper is
It can be determined by detecting the amount of furfural, which is a product produced by the deterioration of the insulating paper, in the insulating oil. Therefore, various methods for extracting furfural from the above insulating oil have been proposed so far. In addition, the furfurals represent a concept including furfural (also referred to as furaldehyde) and furfural derivatives such as hydroxymethylfurfural.

As a method for extracting furfural from insulating oil, for example, a liquid-liquid extraction method in which an insulating oil such as mineral oil and an extraction liquid are brought into contact with each other, or a solid-liquid extraction in which insulating oil is brought into contact with a solid such as silica is used. Method is known (IEC (Intern
ational Electrotechnical Commission), 1198,
1993). Further, in the liquid-liquid extraction method, methanol, acetonitrile, water / methanol, water / acetonitrile and the like are used as the organic solvent which is an extraction liquid.
As a method for separating and analyzing the extracted furfurals,
A high performance liquid chromatograph is used and an ultraviolet photometer is used as a detector. With such a separation and analysis device, the furfural in the insulating oil is quantified, and the life of the oil-filled electrical device is diagnosed.

[0004]

In the method for diagnosing the life of the oil-filled electrical equipment as described above, in the case of the liquid-liquid extraction method, insulating oil remains in the organic solvent that is the extraction liquid. When it is attempted to separate this into an organic solvent layer and an insulating oil layer by standing, it takes about 8 to 20 hours to complete the separation into two layers. Further, when the insulating oil remains in the organic solvent layer, there is a problem that the analysis equipment is damaged and the analysis of furfural is disturbed.
Further, in the case of the solid-liquid extraction method, although there is almost no insulating oil remaining in the extraction liquid, there is a problem that the operation is complicated.

Therefore, it has been proposed to use a centrifugal separator in the liquid-liquid extraction method to shorten the time required for separation into two layers (JP-A-7-26).
3243). However, also in this method, it is necessary to extract the furfural by mixing the oil of the sample with the organic solvent and stirring the mixture, transferring them one by one into a centrifuge container, and then centrifuging them one by one.
Therefore, the work becomes complicated when the furfurals are individually extracted from a large number of samples.

[0006] Therefore, the present invention provides a furfural extraction method and a furfural extraction apparatus capable of individually extracting furfural in the oil by a simple operation even when a large number of sample oils are present. It was done as a purpose.

[0007]

Means for Solving the Problems and Effects of the Invention The invention according to claim 1 made in order to achieve the above object, is a method for extracting furfural in oil to extract furfural contained in oil. , An organic solvent that dissolves furfural and the above oil are mixed and stirred, and the mixed solution after the stirring is allowed to stand to separate the organic solvent and the oil into two layers,
By generating a vortex in the liquid after the separation that does not result in agitation, the oil droplets suspended in the organic solvent or adhered to the wall surface of the container are aggregated or coalesced, and subsequently, after the vortex is extinguished. The organic solvent is collected to extract furfural.

According to the method of the present invention thus constructed,
First, an organic solvent that dissolves furfural and the above oil are mixed and stirred. By this agitation, the furfural contained in the oil moves to the organic solvent side by the partial orientation flow. Then, the mixed solution after the stirring is left to stand to separate the organic solvent and the oil into two layers. This separation need not be complete, and oil droplets may be suspended in the organic solvent as follows. Therefore, this standing is sufficient for a short time of about 1 minute. Then, a vortex is generated in the liquid after the separation to the extent that stirring is not achieved. Then, the oil droplets floating in the organic solvent or adhering to the wall surface of the container are aggregated or united by this vortex flow. Therefore, by removing the vortex and collecting the organic solvent, the furfural can be satisfactorily extracted without containing oil.

As described above, in the present invention, the organic solvent and the oil are almost completely separated by generating the vortex flow. Moreover, in the step of generating the vortex and the step of stirring that precedes it, there is no need to transfer the container containing the oil and the organic solvent, and the operation is extremely simple. For example, by controlling the strength of the vortex strongly or weakly, the stirring or the aggregation / coalescence of oil droplets can be performed in the same manner. Further, the generation and stirring of the vortex can be simultaneously performed on a large number of samples if the apparatus is appropriately configured.

Therefore, according to the present invention, even when a large number of sample oils are present, the furfural compounds in the oil can be individually extracted by a simple operation. Therefore, if the method of the present invention is used, life diagnosis for a large number of oil-filled electrical devices can be performed quickly and easily. Needless to say, the oil in the present invention is not limited to insulating oil for oil-filled electrical equipment.

In addition to the structure of claim 1, the invention of claim 2 is characterized in that the same magnetic stirrer is used for the stirring and the generation of the vortex. In the magnetic stirrer, the rotation speed of the stirrer can be freely set, so that the stirring can be performed by setting the rotation speed to a high speed, and the swirl can be generated by setting the rotation speed to a low speed. That is, it is not necessary to transfer the container containing the oil and the organic solvent, and it is not necessary to move the container, and the steps of stirring, standing and generating a vortex can be continuously performed. Moreover, it is extremely easy to perform the same control for a large number of magnetic stirrers. Therefore, in the present invention, in addition to the effect of the invention described in claim 1, even when a large number of sample oils are present, the effect that furfurals in the oil can be individually extracted more quickly and easily Occurs.

According to a third aspect of the present invention, there is provided an apparatus for extracting furfural in oil for extracting furfural contained in oil, wherein an organic solvent for dissolving furfural and the oil are mixed and stirred. Stirring means, vortex flow generating means for generating a vortex flow that does not result in stirring in a mixture of the organic solvent and the oil separated into two layers by allowing the mixed liquid after the stirring to stand, and the vortex flow Extraction means for extracting the above-mentioned organic solvent to extract furfurals after disappearance.

In the present invention thus constructed, first,
The stirring means mixes the organic solvent that dissolves the furfural with the oil and stirs. By this agitation, the furfural contained in the oil moves to the organic solvent side by the partial orientation flow. Subsequently, the mixed solution after the stirring is allowed to stand to separate the organic solvent and the oil into two layers (this separation does not have to be complete as in claim 1), and then a vortex flow is generated. If a vortex flow that does not result in agitation is generated by the means, the oil droplets floating in the organic solvent or adhering to the wall surface of the container can be aggregated or coalesced, as in the first aspect of the invention.

Then, after the vortex disappears, the extraction means extracts furfural by collecting the organic solvent. As a result, similarly to the invention described in claim 1, the furfural contained in the oil can be satisfactorily extracted without containing the oil. Therefore, also in the present invention, as in the case of the first aspect of the present invention, even when many sample oils are present, the furfural compounds in the oil can be individually extracted by a simple operation. Therefore, by analyzing the furfural compounds extracted according to the present invention, it is possible to quickly and easily perform life diagnosis for a large number of oil-filled electrical devices.
Needless to say, the oil is not limited to the insulating oil of the oil-filled electric device in the present invention.

According to a fourth aspect of the invention, in addition to the structure of the third aspect, the stirring means and the vortex flow generating means are the same magnetic stirrer.
Therefore, also in the present invention, as in the invention according to claim 2,
The operations of the stirring means and the vortex flow generating means can be performed without the need to transfer the container containing the oil and the organic solvent and the need to move the container. Moreover, it is extremely easy to perform the same control for a large number of magnetic stirrers. Therefore, in the present invention, in addition to the effect of the invention described in claim 3, even when a large number of sample oils are present, it is possible to extract furfural in the oil individually more quickly and easily. Occurs.

According to a fifth aspect of the present invention, in addition to the structure of the fourth aspect, the magnetic stirrer is driven at a speed sufficient for mixing and stirring the organic solvent and the oil, and the mixing after the stirring is performed. Magnetic stirrer control means for stopping the magnetic stirrer for a time sufficient to separate the liquid into two layers of the organic solvent and the oil, and subsequently driving the magnetic stirrer at a speed sufficient to generate the vortex flow. Is further provided.

The magnetic stirrer control means of the present invention first drives the magnetic stirrer at a speed sufficient to mix and stir the organic solvent and the oil. Thereby, the magnetic stirrer can be operated as the stirring means. Then, the magnetic stirrer control means stops the magnetic stirrer for a time sufficient to separate the stirred mixed liquid into two layers of the organic solvent and the oil. As a result, the organic solvent and the oil are separated into two layers. Note that, as mentioned above, this separation need not be perfect.

Subsequently, the magnetic stirrer control means drives the magnetic stirrer at a speed sufficient to generate the vortex flow. As a result, the magnetic stirrer can be operated as the eddy current generating means. As described above, according to the present invention, the operations from the stirring to the generation of the vortex can be performed fully automatically.
Therefore, in the present invention, in addition to the effect of the invention described in claim 4, the effect that the furfural in the oil can be more easily extracted can be obtained.

According to a sixth aspect of the present invention, in addition to the structure according to any of the third to fifth aspects, the extraction means inserts a needle into the organic solvent after the vortex disappearance to suck the organic solvent. Suction means, a needle moving means for moving the needle to the vicinity of an analyzer for quantitatively analyzing furfural in the organic solvent, and an organic solvent sucked by the suction means,
Ejection means for ejecting toward the analyzer through the needle.

As described above, in the extraction means of the present invention, the suction means inserts the needle into the organic solvent after the vortex disappearance, sucks the organic solvent, and quantitatively analyzes furfural in the organic solvent. The needle moving means moves the needle to the vicinity of. Further, the discharge means discharges the organic solvent sucked by the suction means toward the analyzer through the needle.

Therefore, in the present invention, the operations from collecting the organic solvent after the vortex disappearance to subjecting it to analysis by the analyzer are automatically executed by sequentially operating the suction means, needle moving means, and discharge means. can do. Therefore,
In the present invention, in addition to the effects of the invention described in any of claims 3 to 5, there is an effect that it is easier to extract and analyze furfural in oil.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an apparatus for extracting furfural in oil to which the present invention is applied (hereinafter, simply referred to as an extraction apparatus) 1.
2 is a right side view showing the configuration of the extracting device 1. FIG. In addition, as shown in FIG. 1, the extraction apparatus 1 of the present embodiment is arranged adjacent to a liquid chromatograph apparatus 70 (which may be a general one) as an analysis apparatus, and a filtering unit 53 described later is provided in the liquid chromatograph apparatus. Used by connecting to 70 columns (not shown).

As will be described below, the extraction device 1 accommodates the insulating oil 80 (see FIG. 6) of the oil-filled electric device in the container body 3 and allows the container 7 sealed by the lid 5 to be attached. The furfural contained in the insulating oil 80 contained in the container 7 is extracted and sent to the liquid chromatograph 70. The lid 5 of the container 7 used in the extraction device 1 is provided with a packing 9 in which a cross cut 9a is formed as shown in the plan view of FIG. 3, and an injection needle described later is provided through the cut 9a. 43 and 45 are containers 7
It can be inserted inside.

As shown in FIGS. 1 and 2, the extraction device 1 is
A turntable 11 capable of mounting up to 30 containers 7 is provided in the lower part, and a magnetic stirrer 13 for stirring the liquid in the container 7 is provided below the container mounting part of the turntable 11 for mounting each of the above containers. It is provided for each copy. The magnetic stirrer 13 is the turntable 11
It is fixed on a disk-shaped stirrer substrate 15 that rotates integrally with the rotary table, and a pulley 17 that rotates integrally with the turntable 11 and the stirrer substrate 15 is provided below the turntable 11 and the stirrer substrate 15.

Further, the extraction device 1 includes a turntable 11
Box-shaped table part 2 configured so that the upper surface is exposed
1, a mechanism portion 23 adjacent to the table portion 21 is formed in a vertically long box shape, and a mechanism portion 23 for supporting various drive mechanisms described later, and a protrusion formed parallel to the table portion 21 at the upper end of the mechanism portion 23, A control unit 29 provided with an operation panel 25 and a rotary volume 27 is provided. Table part 21
Square holes 21a are formed on the front and left and right side surfaces of the casing of
Although a side cover is usually attached to this portion, the side cover is omitted in FIGS. 1 and 2 for convenience of description. Further, the bottle rack 31 is provided on the upper end surface of the mechanism unit 23.
Is provided, and three 2 liter glass bottles 33 storing acetonitrile 90 as an organic solvent can be attached thereto.

The pulley 17 which rotates integrally with the turntable 11 is connected to a table rotation motor 35 provided in the mechanism portion 23 via a belt 37 as shown in FIG. Therefore, the turntable 11 and the stirrer substrate 15 are rotated according to the rotation of the table rotation motor 35.
Rotates.

As shown in FIG. 1, a sample holding valve 41, injection needles 43 and 45, and a three-way valve 47 are provided on the front surface of the mechanism portion 23. The injection needle 43 is configured to be horizontally movable from directly above the container 7 mounted on the turntable 11 to immediately above the filtration unit 53 by a needle horizontal movement mechanism 51 in which the arm is horizontally swung.
Vertically inserted into the container 7 by the needle lifting / moving mechanism 55.
It is designed to be removed. Further, the injection needle 43 is double-structured, a negative pressure from the vacuum pump 57 (FIG. 2) is applied to the inside via the sample holding valve 41, and an air Air (from the air pump 59 (FIG. 2) to the outside is supplied to the outside. (See FIG. 6).

Similarly to the injection needle 45, the needle horizontal movement mechanism 6 is also provided.
1 and a needle lifting / lowering movement mechanism 63 are provided, and the injection needle 45
The acetonitol 90 stored in the glass bottle 33 can be sent via the three-way valve 47. Further, as shown in FIG. 2, an electronic control circuit 65 for controlling each of the above mechanisms is provided inside the mechanism section 23.
And a fan 67 for cooling the electronic control circuit 65.
And are provided.

As shown in FIG. 4, the electronic control circuit 65 includes
It is configured as a microcomputer including a CPU 65a, a ROM 65b, and a RAM 65c, receives commands from the operation panel 25, and moves the needle horizontal movement mechanisms 51, 6
1, needle lifting and moving mechanism 55, 63 three-way valve 47, vacuum pump 57, air pump 59, sample holding valve 41,
A drive signal is output to the table rotation motor 35 and each magnetic stirrer 13.

Next, the furfural extraction process by the electronic control circuit 65 will be described with reference to the flowchart of FIG. As shown in FIG. 5, when the process is started, the electronic control circuit 65 first performs a solvent injection process on the container 7 having the number designated by the operation panel 25 in S1 (S represents a step: the same applies hereinafter). I do. That is, the container mounting portions of the turntable 11 are assigned numbers 1 to 30.

Therefore, in this solvent injection process, the table rotation motor 35 and the needle horizontal movement mechanism 61 are driven to dispose the injection needle 45 directly above the container 7 corresponding to the instruction, and then the needle elevation movement mechanism 63. Is driven to insert the injection needle 45 into the container 7 through the notch 9a. Furthermore, three-way valve 4
After driving 7 to inject 2 ml of acetonitrile 90 into the container 7, the needle elevating and moving mechanism 63 is driven to inject the injection needle 45.
Is removed from the container 7. In S1, the operation panel 2
Such processing is sequentially executed for all the containers 7 designated by 5.

In the subsequent S2, the acetonitril 90 is obtained in S1.
The magnetic stirrer 13 disposed below each of the containers 7 into which is injected is rotated at a high speed, and the insulating oil 80 and the acetonitol 90 in the containers 7 are mixed and stirred. The rotation speed at this time can be set for each magnetic stirrer 13 by the rotation volume 27, and here, 750 rp.
m. In addition, in this step, all magnetic stirrers 13 including those without the container 7 are attached.
However, there is no problem even if the same processing is performed all at once (the same applies to S4 described later).

In the subsequent S3, all the magnetic stirrers 13 are allowed to stand for 1 minute, and in S4, the magnetic stirrer 13 driven in S2 is rotated at a low speed this time to make the container 7
A vortex flow is generated in the mixed liquid inside the liquid to a degree that does not result in stirring. The rotation speed at this time can also be set for each magnetic stirrer 13 by the rotation volume 27, and here, 25
Set to 0 rpm.

Then, in S5, a solvent extraction process for extracting the acetonitol 90 in the container 7 is performed, and the process is completed. In this solvent extraction process, the table rotation motor 35
And, the needle horizontal movement mechanism 51 is driven to arrange the injection needle 43 directly above the corresponding container 7, and then the needle elevation movement mechanism 55 is driven to insert the injection needle 43 into the container 7 through the notch 9a. To do. At the time of this insertion, at least the injection needle 4
After the tip of 3 has passed through the packing 9,
Until it is inserted into the 0 layer, the air pump 59 as a blowing means is driven to drive air from the periphery of the injection needle 43.
(See FIG. 6) is injected.

Further, subsequently, the vacuum pump 57 and the sample holding valve 41 are driven to collect the acetonitol 90, and the needle elevating and moving mechanism 55 is driven to move the injection needle 43 into the container 7.
Remove from. Then, the needle horizontal movement mechanism 51 is driven to dispose the injection needle 43 directly above the filtering unit 53, and the sample holding valve 41 is connected to the atmospheric pressure to drop the collected acetonitrile 90 on the filtering unit 53. To do. Then, the filtering unit 53 filters a small amount of the insulating oil 80 mixed in the acetonitol 90, and the liquid chromatograph device 70 quantitatively analyzes the furfural. The electronic control circuit 65 performs the process of S5 in the same manner as in S1.
When the execution is sequentially completed for all the containers 7 instructed by 5, the processing is temporarily ended.

Next, the insulating oil 8 during the above-mentioned processing is executed.
The behavior of 0 and acetonitril 90 will be described with reference to FIG. At the time when the acetonitril 90 is injected in S1, the insulating oil 80 precipitates on the bottom of the container body 3 as shown in FIG. 6 (A), and the acetonitril 90 is disposed thereon. At this point, almost all of the furfural remains dissolved in the insulating oil 80.

At S2, the stirrer 13a of the magnetic stirrer 13 is rotated at 750 rpm, and FIG.
As shown in, the insulating oil 80 and the acetonitol 90 are mixed and stirred. By this stirring, the furfural contained in the insulating oil 80 moves to the acetonitril 90 side by the partial orientation flow.

Subsequently, when the mixed solution after the stirring is left to stand for 1 minute (S3), the acetonitol 90 and the insulating oil 80 are separated into two layers. This separation is not complete as shown in FIG. 6 (C), and oil droplets 80a may float in acetonitol 90 or oil droplets 80a may adhere to the inner wall surface of the container body 3. is there.

Then, in S4, the stirring bar 13a is set to 250 rpm.
6D, it is possible to generate a vortex flow in the liquid after separation to the extent that stirring is not achieved. Then, the oil droplets 80a floating in the acetonitol 90 or adhering to the wall surface of the container body 3 coalesce at the center of the vortex by this vortex. Further, a part of the oil droplet 80a coalesces with the insulating oil 80 that has settled on the bottom of the container body 3. After the vortex disappears, a spherical oil droplet 80a is formed at the center of the liquid surface of the acetonitol 90, as shown in FIG. 6 (E).

In S5, the injection needle 43 is inserted into the container 7 and air Air is jetted from around the same, so that FIG.
As shown in (F), the oil droplet 80a is removed from immediately below the injection needle 43, and then the acetonitolyl 90 is collected via the injection needle 43. By the above operation, the furfural dissolved in the acetonitril 90 can be satisfactorily extracted without containing the insulating oil 80. Then, after the insulating oil 80 is more surely removed from the sampled acetonitrile 90 through the filtration unit 53, the quantitative analysis of the furfural by the liquid chromatograph device 70 is performed, so that the oil-filled electrical device Life span can be diagnosed.

The above-mentioned injection of the air Air is not always necessary. Even if the injection needle 43 penetrates the oil droplet 80a, at the stage of FIG.
Since (including a) and acetonitrile 90 are completely separated from each other, the injection of the injection needle 43 into the layer of acetonitol 90 reliably prevents the mixing of the insulating oil 80. That is, when the injection needle 43 penetrates the oil droplet 80a, the insulating oil 80 hardly enters the injection needle 43. Further, since the insulating oil 80 has been almost completely removed at the stage when the acetonitol 90 is collected by the injection needle 43, the filtering unit 53 may be a very simple one. Depending on the quality of the insulating oil 80 and the performance of the liquid chromatograph device 70, it is possible to omit the filtering unit 53.

As described above, in this embodiment, the acetonitol 90 and the insulating oil 80 are separated by generating the vortex flow by the magnetic stirrer 13. Therefore, it is not necessary to transfer or move the container containing the insulating oil 80 or the like between the step of generating the vortex and the step of stirring that precedes it, and the steps of stirring, standing, and generating the vortex are continuously performed. Then you can run.

Further, since the generation of vortex and the stirring can be executed simultaneously for a large number of containers 7, even when a large number of insulating oils 80 of samples exist, the furfural in the oil can be individually extracted by a simple operation. be able to. Therefore, in the present embodiment, it is possible to quickly and easily perform life diagnosis for many oil-filled electrical devices. In addition, since the steps relating to the extraction are fully automated from the injection of acetonitol 90 to the delivery to the liquid chromatograph 70, the life diagnosis is extremely easy. That is, it is possible to automate the analysis work that is performed by first-class scientists.

In the above embodiment, the magnetic stirrer 13 is used as the stirring means and the vortex flow generating means, and the injection needle 43, the vacuum pump 57, the sample holding valve 41, the needle horizontal movement mechanism 51, and the needle up / down movement mechanism 55 are provided. The electronic control circuit 65 serves as a magnetic stirrer control means for the extraction means, the needle horizontal movement mechanism 51, the needle elevation movement mechanism 55, the vacuum pump 57 and the sample holding valve 41 serve as the suction means, and the needle horizontal movement mechanism 51 and the needle elevation movement. The mechanism 55 corresponds to the needle moving means, and the sample holding valve 41 corresponds to the discharging means.

Further, the present invention is not limited to the above-described embodiments, and can be implemented in various forms without departing from the gist of the present invention. For example, the magnetic stirrer 13 may be used to manually stir, settle, and generate a vortex flow manually by an operator turning the switch on and off.

As the stirring means and the vortex flow generating means, various structures other than the magnetic stirrer 13 can be adopted, and different means may be used respectively. However,
When the same means is used as the stirring means and the vortex flow generating means, the work becomes easier. Further, the present invention can be applied to the detection of furfural with respect to oils other than the insulating oil 80, and various organic solvents can be used.

[Brief description of drawings]

FIG. 1 is a front view showing a configuration of an extraction device to which the present invention is applied.

FIG. 2 is a right side view showing the configuration of the extraction device.

FIG. 3 is a plan view showing a configuration of a container used in the extraction device.

FIG. 4 is a block diagram showing a configuration of a control system of the extraction device.

FIG. 5 is a flowchart showing a furfural extraction process in the control system.

FIG. 6 is an explanatory diagram showing the behavior of insulating oil and the like due to the processing.

[Explanation of symbols]

1 ... Extractor 7 ... Container 9 ... Packing
11 ... Turntable 13 ... Magnetic Stirrer 13a ... Stirrer
15 ... Stirrer substrate 35 ... Table rotation motor 41 ... Sample holding valve 43, 45 ... Injection needle 47 ... Three-way valve 5
1, 61 ... Needle horizontal movement mechanism 53 ... Filtration section 55, 63 ... Needle elevating movement mechanism
57 ... Vacuum pump 59 ... Air pump 65 ... Electronic control circuit 70 ... Liquid chromatograph device 80 ... Insulating oil 80a ... Oil droplet 90 ... Acetonitrile

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Claims (6)

[Claims] 1. A method for extracting furfural in oil for extracting furfural contained in oil, comprising mixing an organic solvent for dissolving furfural with said oil and stirring, and mixing after the stirring. The liquid is left to stand to separate the organic solvent and the oil into two layers, and a vortex is generated in the liquid after the separation to the extent that stirring is not performed, so that the liquid floats in the organic solvent or adheres to the wall surface of the container. A method for extracting furfural in oil, comprising aggregating or coalescing the formed oil droplets, subsequently eliminating the vortex, and collecting the organic solvent to extract furfural. 2. Due to the stirring and the generation of the vortex,
The method for extracting furfural in oil according to claim 1, wherein the same magnetic stirrer is used. 3. An apparatus for extracting furfural in oil for extracting furfural contained in oil, comprising a stirring means for mixing and stirring an organic solvent for dissolving furfural and the oil, and the stirring. A vortex generating means for generating a vortex that does not result in agitation in a mixture of the organic solvent and the oil separated into two layers by allowing the later mixed liquid to stand, and the organic solvent after the vortex disappears. An apparatus for extracting furfural in oil, comprising: an extracting means for collecting and extracting furfural. 4. The stirring means and the vortex flow generating means,
An apparatus for extracting furfural in oil according to claim 3, wherein the same magnetic stirrer is used. 5. The magnetic stirrer is driven at a speed sufficient to mix and stir the organic solvent and the oil,
The magnetic stirrer is stopped for a time sufficient to separate the mixed liquid after the stirring into the organic solvent and the oil into two layers, and then the magnetic stirrer is driven at a speed sufficient to generate the vortex. 5. The apparatus for extracting furfural in oil according to claim 4, further comprising a magnetic stirrer control means. 6. The extraction means up to the vicinity of a suction means for inserting a needle into the organic solvent after the vortex disappearance and for sucking the organic solvent, and an analyzer for quantitatively analyzing furfural in the organic solvent. 6. A needle moving means for moving the needle, and a discharging means for discharging the organic solvent sucked by the sucking means toward the analyzer through the needle. An apparatus for extracting furfural in oil according to any one of 1.