JP2023004677A - Continuous liquid-liquid separator and continuous liquid-liquid separation method - Google Patents

Abstract

To provide a continuous liquid-liquid separator capable of performing various solution-based phase separations with simple construction.SOLUTION: A continuous liquid-liquid separator has a structure which introduces a biphase liquid comprising at least two or more components which do not mix completely with each other to separate into two phases of light and heavy liquids from an input port provided on one side of a chamber and discharge the light and heavy liquids from respective discharge ports provided on the other side. The separator comprises a boundary face adjustment mechanism adjusting the boundary face of the light and heavy liquids between the input port and discharge ports. The mechanism comprises: two mesh plates having a vertical interval diminishing progressively from an upstream side toward a downstream side and separating the biphase liquid into vertical two layers; and a vertical layer separator neighboring to the downstream end parts of two mesh plates to form a Y-shaped cross section together with two mesh plates. Height of the boundary face of vertical two layers fixed by the vertical layer separator is same as that of the discharge ports of the light and heavy liquids.SELECTED DRAWING: Figure 1

Description

The present invention is a continuous liquid that continuously separates a two-phase liquid consisting of at least two or more components that are completely immiscible with each other and separate into two phases, a light liquid and a heavy liquid, according to their specific gravities. It relates to separators and continuous liquid-liquid separation methods.

In the process of synthesizing chemicals, conventionally, production was carried out by a batch method that repeats reactions, separation, and purification in multiple stages. . Therefore, in recent years, in order to reduce the environmental load and improve cost competitiveness, we have achieved both a reduction in waste and a high yield by continuously conducting multi-stage reactions and separating and refining reaction products. In addition, there has been a shift to the flow method, which aims for automatic operation and compactness.
As a means for separating and purifying the product in the flow method, a liquid to be extracted containing the product is brought into contact with an extracting liquid agent immiscible with the liquid to be extracted, and a two-phase liquid consisting of the liquid containing the product and the liquid to be extracted is formed. , are known in the prior art for liquid-liquid separation according to their respective specific gravities.

For example, in Patent Document 1, after layer-separating a liquid mixture of liquids having different specific gravities that flowed into a chamber from a liquid inflow section, the liquid in the upper layer and the liquid in the lower layer are discharged from the upper outflow section and the lower outflow section, respectively. In the continuous liquid separation apparatus, the position of the interface in the chamber is monitored by the interface detection means, and the flow rate adjustment means provided in at least one of the outflow paths is controlled so as to maintain the position of the interface at a predetermined position. is described.

In addition, Patent Document 2 discloses a continuous liquid-liquid separator that separates a two-phase liquid into a light liquid and a heavy liquid, in which the light liquid is discharged from the upper light liquid outlet and the heavy liquid is discharged from the lower heavy liquid outlet. A heavy liquid-permeable porous membrane is installed at the heavy liquid outlet, and the heavy liquid-permeable porous membrane is even affected by the differential pressure between the upstream and downstream of the heavy liquid-permeable porous membrane. , a material and a pore size that generate a heavy liquid retention force that prevents permeation of the light liquid, and the light liquid discharge port has a pore size that does not allow the pressure upstream of the heavy liquid permeation porous membrane to exceed the heavy liquid retention force. , describes a separator provided with a light liquid permeable porous membrane having a membrane area.

Japanese Patent Application Laid-Open No. 2008-6387 JP 2019-130484 A

In a conventional continuous liquid-liquid separator, as described in Patent Document 1, in order to keep the position of the interface between the separated upper layer and lower layer constant, the liquid feeding amount and liquid feeding speed conditions such as an interface monitoring device and flow rate adjusting means An accessory device was required to adjust the
On the other hand, in the continuous liquid-liquid separator described in Patent Document 2, the heavy liquid and the light liquid are separated by using a porous membrane that allows only one of the heavy liquid and the light liquid to pass through and does not allow the other to pass through. The isolation eliminates the need for ancillary devices to monitor interfaces or regulate flow rates. However, in Patent Document 2, since the permeation and non-permeation selectivity of the porous membrane for different liquid types is used, the material and pore size of the porous membrane are adjusted according to the wettability of each heavy liquid and light liquid. necessary and lacks versatility.

The present invention has been made in view of the current situation, and does not require an auxiliary device for monitoring the interface or adjusting the flow rate, and can perform phase separation of various solution systems with a simple configuration. The object is to provide a liquid separator.

As a result of earnest investigations in order to solve the above problems, the present inventors found that a two-phase liquid separated into two phases, a light liquid and a heavy liquid, which are completely immiscible with each other, continuously flows into a chamber where the interface between the two phases is formed. The inventors have found that the above problem can be solved by providing an interface adjustment mechanism for fixing the height, and by making the heights of the interface, the light liquid discharge port, and the heavy liquid discharge port the same.

In order to solve the above problems, the present invention employs the following means based on the above findings.
(1) A two-phase liquid composed of at least two components that are completely immiscible with each other and separated into two phases, a light liquid and a heavy liquid, is introduced from an inlet provided on one side of the chamber, and A continuous liquid-liquid separator having a structure for discharging the light liquid and the heavy liquid respectively from the light liquid discharge port and the heavy liquid discharge port provided on the side surface of the and an interface adjustment mechanism that adjusts the interface between the two-phase liquid and the heavy liquid. The interface adjustment mechanism has two mesh plates that gradually decrease in vertical spacing from the upstream side to the downstream side and separate the two-phase liquid into two upper and lower layers. , and an upper and lower layer separator adjacent to the downstream end of the two mesh plates and forming a Y-shaped cross section together with the two mesh plates, and is fixed by the upper and lower layer separators. and the heights of the light liquid outlet and the heavy liquid outlet are the same.
(2) The continuous-liquid-liquid separator according to (1) above, wherein the ends of the two mesh plates on both outlet sides have minute gaps for removing air bubbles.
(3) A method for continuously separating a two-phase liquid consisting of at least two components that are completely immiscible with each other and separated into two phases, a light liquid and a heavy liquid, wherein an inlet is provided on one side. , the two-phase liquid is continuously introduced into a chamber having a light liquid outlet and a heavy liquid outlet with the same height on the other side, and between the inlet and the outlet, from the upstream side to the downstream side The two-phase liquid is separated into upper and lower layers by two mesh plates that are installed with a gradually decreasing vertical interval toward , suppress the permeation of the heavy liquid, and allow the light liquid that floats to permeate. A Y-shaped cross section is formed together with the mesh plate, the interface between the upper and lower layers is fixed by the upper and lower layer separators having the same height as the both discharge ports, and the light liquid is discharged from the light liquid discharge port and the heavy liquid discharge port. and a continuous liquid-liquid separation method, respectively discharging the heavy liquid.

According to the present invention, there is provided a continuous liquid-liquid separator and a continuous liquid-liquid separation method with high versatility that can perform phase separation of various solution systems without requiring an accessory device for monitoring and adjusting the interface. be able to.

BRIEF DESCRIPTION OF THE DRAWINGS A side view schematically showing the outline of a continuous liquid-liquid separator according to the present invention. Explanatory diagram of a conventional settler with a light liquid discharge port and a heavy liquid discharge port provided at the top and bottom, respectively, when the heights of both discharge ports are different Explanatory diagram for the same settler with the same discharge port height and different interface height Explanatory drawing of the same settler when the height of both outlets and the interface are the same Schematic diagram of capillary force when the heavy liquid is the aqueous phase, the mesh plate is hydrophilic, and there is no pressure from the aqueous phase to the mesh plate. Schematic diagram of capillary force when the heavy liquid is in the aqueous phase, the mesh plate is hydrophilic, and there is pressure from the aqueous phase to the mesh plate. Photographs showing liquid feeding states when the amount of heavy liquid in the separator according to the present invention is larger (Example 1) and when the amount of light liquid is larger (Example 2)

In the present invention, a two-phase liquid composed of at least two components that are completely immiscible with each other and separated into two phases, a light liquid and a heavy liquid, is flowed in a mixed state, and the upper and lower layers have a constant interface height. A continuous liquid-liquid separation device and a continuous liquid-liquid separation method that can separate into two layers and discharge each phase from a light liquid discharge port and a heavy liquid discharge port at the same height as the interface height, and a continuous liquid-liquid separation method. In order to fix the liquid-liquid interface at the same height as both outlets, it is characterized by installing an interface adjustment mechanism consisting of two mesh plates and upper and lower layer separators.
An outline of a continuous liquid-liquid separator according to an embodiment of the present invention (hereinafter referred to as "this embodiment") is schematically shown in FIG.
Each configuration of the present embodiment will be described in detail below, but these are for the purpose of explaining the present invention and do not limit the scope of the present invention.
In this specification, "-" indicating a numerical range is used to include the numerical values before and after it as a lower limit and an upper limit.

<Heights of light liquid outlet, heavy liquid outlet, and interface between light liquid and heavy liquid>
First, the necessity of making the heights of the light liquid outlet and the heavy liquid outlet equal to the interface between the light liquid and the heavy liquid will be described.
As shown in FIG. 2, in the case of a settler in which a light liquid discharge port and a heavy liquid discharge port are respectively provided above and below, if there is a difference in pressure received from the liquid at both discharge ports, the heavy liquid discharge port of the lower phase Therefore, an interface monitoring device, a discharge control valve, etc. are required.
Also, as shown in FIG. 3, when both discharge ports are at the same height, when the interface is lower than both discharge ports, the light liquid is preferentially discharged, and when the interface is higher than both discharge ports, the heavy liquid is discharged. Liquid is preferentially discharged.
Therefore, as shown in FIG. 4, when the height of both the light liquid outlet and the heavy liquid outlet is the same as the height of the liquid-liquid interface, the upper and lower phases are discharged from the outlets in a well-balanced manner. However, since the liquid-liquid interface is not always constant, it is necessary to fix the height of the liquid-liquid interface to be the same as the height of both outlets.

In the present invention, in order to separate the two-phase liquid into upper and lower layers and fix the liquid-liquid interface at the same height as both outlets, an interface adjustment mechanism consisting of two mesh plates and upper and lower layer separators is installed. It has characteristics.

In fact, since each outlet has a finite size in the vertical direction, the same height means that the lower end of the light liquid outlet, the upper end of the heavy liquid outlet, and the upper and lower layer separators. It means that the fixed liquid-liquid interface is at the same height.

<Mesh plate>
The two mesh plates in this embodiment have openings that have a force (capillary force) that fixes the heavy liquid to the mesh plates. Capillary force in the mesh plate, that is, control of wettability is only required for heavy liquids.
The shape of the opening may be rectangular or circular, but in the case of a rectangular shape, the opening diameter is converted to a circular shape with a radius of r.
Since the capillary pressure Pc of the heavy liquid in the opening of radius r is represented by Equation 1 below, the capillary force depends on the opening diameter r.
(Formula 1)
Pc=2γ cos θ/r
(γ: interfacial tension between heavy liquid and light liquid, θ: contact angle of heavy liquid)

FIG. 5 shows the capillary force when the heavy liquid is the aqueous phase, the material of the mesh plate is hydrophilic, and there is no pressure of the aqueous phase on the mesh plate. It is a phase, the material of the mesh plate is hydrophilic, and it is a figure explaining the capillary force when there is pressure of the aqueous phase applied to the mesh plate. If the mesh plate has an affinity for the heavy liquid (aqueous phase), the heavy liquid (aqueous phase) will flow through the mesh plate due to the capillary force at the openings of the mesh plate, regardless of whether there is pressure from the aqueous phase or not. fixed to
When the heavy liquid is the oil phase, a hydrophobic mesh plate can be used regardless of whether the light liquid is the oil phase or the water phase.

The opening diameter of the mesh plate is preferably about 0.2 to 5.0 mm, more preferably about 0.75 to 2.0 mm. .

In the present embodiment, the material of the mesh plate is not particularly limited, but examples of hydrophilic materials include hydrophilic polytetrafluoroethylene, acrylic resin, polyamide, polyimide, polyester, polycarbonate, polyether, polyurethane, ceramics, and metals. etc. Polymethacrylate is particularly preferred.
Examples of hydrophobic materials include polytetrafluoroethylene (PTFE), polyolefin, polystyrene, polyphenylene vinylene, and polyvinyl chloride.

These two mesh plates divide the channel into three parts, upper, middle, and lower, on the upstream side in the chamber, but are arranged so that the vertical interval gradually decreases toward the downstream side. As a result, the intermediate channel is gradually narrowed, and only the upper channel and the lower channel are formed on the downstream side.
When the liquid volume in the chamber of the heavy liquid in the two-phase liquid exceeds the height of the separator, the light liquid flows through the gap at the upstream edge of the mesh plate and is concentrated in the upper channel, while the heavy liquid flows downward. The two-phase liquid is concentrated in the channel and the intermediate channel, but since the intermediate channel gradually narrows, the two-phase liquid is separated into upper and lower layers of light liquid and heavy liquid at the downstream end of the two mesh plates.
When the liquid volume in the heavy liquid chamber is below the height of the separator, the light liquid flows through the upper channel and the intermediate channel, but the intermediate channel gradually narrows. At the downstream end, the liquid is separated into upper and lower two layers of a light liquid and a heavy liquid.

Two-phase liquids usable in embodiments of the present invention are two-phase liquids composed of at least two components that are completely immiscible with each other and separate into two phases, a light liquid and a heavy liquid, such as water/pentane , water/hexane, water/heptane, water/octane, water/nonane, water/decane, water/cyclohexane, water/decalin, water/benzene, water/toluene, water/xylene, water/nitrobenzene, water/aniline, water /phenol, water/methyl acetate, water/ethyl acetate, water/propyl acetate, water/butyl acetate, water/diethyl ether, water/dipropyl ether, water/dibutyl ether, water/diphenyl ether, water/butanol, water/hexanol , Water/heptanol, Water/octanol, Water/nonanol, Water/decanol, Water/butoxyethanol, Water/triethylamine, Water/chloroform, Water/carbon tetrachloride, Fluorinert/water, Methanol/hexane, Methanol/cyclohexane, Examples include N,N-dimethylformamide/hexane and N-methyl-2-pyrrolidone/hexane.

In addition, two-phase liquids with three or more components, in which an inorganic salt or an organic compound is dissolved in the above two-component two-phase liquid, may also be mentioned. Inorganic salts and organic compounds are dissolved in mixed liquids such as ´-dimethylformamide, water/dimethyl sulfoxide, water/methanol, water/ethylene carbonate, water/acetic acid, and separated into two phases: light liquid and heavy liquid. things are mentioned.

<Upper and lower layer separator>
The upper and lower layer separators in this embodiment are adjacent to the downstream ends of the two mesh plates and form a Y-shaped cross section together with the two mesh plates. It has an action to maintain and fix the
As described at the beginning, by making the height of the light liquid outlet and the heavy liquid outlet equal to the height of the interface between the light liquid and the heavy liquid, the light liquid and the heavy liquid are discharged from the respective outlets in a well-balanced manner. can be drained.

If air bubbles are involved in the inflowing liquid, clogging may occur. Air bubbles should be allowed to escape between the downstream ends of the two mesh plates and the upper and lower layer separators. It may have a minute gap for

(Example 1)
Using an acrylic monomer, a liquid-liquid separator shown in FIG. 1 was produced with a stereolithographic 3D printer (product name: form3 manufactured by formlabs).
This liquid-liquid separator has an interface consisting of two mesh plates on the upstream side and an upper and lower layer separator on the downstream side in a transparent chamber of 13 x 50 x 10 mm having an inlet, a light liquid outlet, and a heavy liquid outlet. Two mesh plates (13 × 15 × 0.5 mm, square opening opening 2 mm) having an adjustment part have an upstream end at a position 20 mm away from the chamber side surface on the inflow side, and a vertical interval of 6 mm The upper and lower layer separators (13 × 15 × 1 mm) are installed so as to gradually decrease symmetrically from the downstream end to the downstream end of the two mesh plates and the side of the chamber on the outlet side. , are installed to be connected at the same height as the light liquid outlet and the heavy liquid outlet.
The light liquid discharge port and the heavy liquid discharge port had an inner diameter of 2 mm and a length of 5 cm.
From the inlet of the liquid-liquid separator, a two-phase liquid of cyclohexane (light liquid) and water colored with food coloring (heavy liquid) was introduced at a flow rate of 1.0 mL/min for light liquid and 0.5 mL/min for heavy liquid. The liquid was sent for 30 minutes.
Cyclohexane was discharged from the light liquid outlet, and only water colored with food coloring was discharged from the heavy liquid outlet.

(Example 2)
A two-phase liquid consisting of cyclohexane (light liquid) and water colored with food coloring (heavy liquid) was prepared using the same liquid-liquid separator as in Example 1, except that the tube inner diameter of the light liquid outlet was changed to 1 mm and the length to 45 cm. was sent at a flow rate of 1.0 mL/min for the light liquid and 0.5 mL/min for the heavy liquid for 30 minutes. Cyclohexane was discharged from the light liquid outlet, and only water colored with food coloring was discharged from the heavy liquid outlet.

(Example 3)
The same liquid-liquid separator as in Example 1 was used and the liquid was fed under the same conditions as in Example 1, except that the square openings of the two mesh plates had a mesh size of 1 mm. Cyclohexane was discharged from the light liquid outlet, and only water colored with food coloring was discharged from the heavy liquid outlet.

(Example 4)
Liquid transfer was performed in the same manner as in Example 1, except that the flow rate of the two-phase liquid was changed to light liquid: 1 mL/min and heavy liquid: 1 mL/min. Cyclohexane was discharged from the light liquid outlet, and only water colored with food coloring was discharged from the heavy liquid outlet.

(Example 5)
Liquid transfer was performed in the same manner as in Example 1, except that the flow rate of the two-phase liquid was changed to light liquid: 4 mL/min and heavy liquid: 4 mL/min. Cyclohexane was discharged from the light liquid outlet, and only water colored with food coloring was discharged from the heavy liquid outlet.

(Example 6)
A mixed solution of 80 vol% 1-butanol/20 vol% water for the light liquid, and a mixed solution of 90 vol% water/10 vol% 1-butanol for the heavy liquid. , Liquid transfer was performed in the same manner as in Example 1, except that the flow rate of the two-phase liquid was changed to 1 mL/min for light liquid and 1 mL/min for heavy liquid. A light liquid was discharged from the light liquid outlet, and a heavy liquid was discharged from the heavy liquid outlet.

(Example 7)
Using polyamide powder, a laser sintering 3D printer (product name: LISA-PRO manufactured by Sinterit) was used to set the inner diameter of the light liquid outlet and the heavy liquid outlet to 1 mm and the opening to 1 mm. A liquid-liquid separator having the same size as in Example 1 was produced except for the above. The light liquid was ethyl acetate, the heavy liquid was water, and the flow rate of the two-phase liquid was changed to light liquid: 1 mL/min and heavy liquid: 1 mL/min. A light liquid was discharged from the light liquid outlet, and a heavy liquid was discharged from the heavy liquid outlet.

(Example 8)
Using polyamide powder, using the same 3D printer as in Example 7, the liquid-liquid separator of the same size as in Example 1 except that the heavy liquid discharge port had a tube inner diameter of 1 mm, a length of 45 cm, and an opening opening of 1 mm. was made. The light liquid is a mixed solution of 10 vol% methanol/90 vol% n-hexane, and the heavy liquid is a mixed solution of 40 vol% methanol/60 vol% n-hexane. /min was changed, the liquid was sent in the same manner as in Example 1. A light liquid was discharged from the light liquid outlet, and a heavy liquid was discharged from the heavy liquid outlet.

(Example 9)
Using polyamide powder, using the same 3D printer as in Example 7, liquid-liquid separation of the same size as in Example 1 except that the tube inner diameter of the light liquid outlet and the heavy liquid outlet was changed to 1 mm and the aperture opening was changed to 1 mm. I made a vessel. A mixed solution of 5 vol% N,N-dimethylformamide/95 vol% n-hexane was used as the light liquid, and a mixed solution of 90 vol% N,N-dimethylformamide/10 vol% hexane was used as the heavy liquid. did A light liquid was discharged from the light liquid outlet, and a heavy liquid was discharged from the heavy liquid outlet.

The configurations of the liquid-liquid separators of Examples 1 to 9 and the liquid feeding conditions are summarized in Table 1 below.
Also, the results of Examples 1 and 2 are shown in the photographs of FIG.

The heavy liquid is shown in dark gray in FIG. In both Example 1 (left figure), in which the amount of heavy liquid in the chamber is larger, and Example 2 (right figure), in which the amount of light liquid in the chamber is larger, the light liquid is discharged from the light liquid outlet. , it was found that only the heavy liquid was discharged from the heavy liquid outlet, and the interface between the upper and lower layers was always kept at a constant height.
Therefore, from Examples 1 and 2, even when the liquid amounts of the light liquid and the heavy liquid are not balanced, the interface between the upper and lower layers is always kept at a constant height, and the light liquid discharge port and the heavy liquid discharge port and are of the same height, it has been found that accurate liquid-liquid separation can be performed automatically.

From Examples 3 to 5, it was found that the effect of the present invention can be sufficiently obtained even when the openings of the mesh plate and the flow rate of the two-phase liquid have a certain width.
From Examples 6 to 9, it was found that continuous phase separation can be effectively performed even if the material of the mesh plate and the combination of the two-phase liquids are changed.
In Examples 2 and 8, the pipe inner diameters of the light liquid discharge port and the heavy liquid discharge port are not balanced, and a load is applied by either the light liquid or the heavy liquid after discharge. It was found that if the difference in the inner diameters of the pipes is small, phase-separated liquids can be obtained from the respective outlets without the interfacial height moving.
From the above, it was demonstrated that the present invention can be used for liquid-liquid separation of various two-phase liquids without requiring strict size setting and liquid transfer conditions.

INDUSTRIAL APPLICABILITY According to the present invention, a continuous liquid-liquid separator having a simple configuration can be used for phase separation of various solution systems, so that it can be used for continuous precision production processes for various chemical products.

Claims (3)

A two-phase liquid consisting of at least two components that are completely immiscible with each other and separate into two phases, a light liquid and a heavy liquid, is introduced from an inlet provided on one side of the chamber and introduced into the other side. A continuous liquid-liquid separator having a structure for discharging a light liquid and a heavy liquid respectively from the light liquid discharge port and the heavy liquid discharge port provided,
An interface adjustment mechanism for adjusting an interface between the light liquid and the heavy liquid is provided between the inlet and the outlet,
The interface adjustment mechanism is
two mesh plates for separating the two-phase liquid into upper and lower layers by gradually decreasing the vertical spacing from the upstream side to the downstream side;
Consisting of upper and lower layer separators adjacent to the downstream ends of the two mesh plates and forming a Y-shaped cross section together with the two mesh plates,
A continuous liquid-liquid separator, wherein the height of the interface between the upper and lower layers fixed by the upper and lower separators is the same as the height of the light liquid outlet and the heavy liquid outlet. 2. The continuous liquid-liquid separator according to claim 1, wherein a minute gap is provided between said downstream end of said two mesh plates and said upper and lower layer separators to allow air bubbles to escape. A method for continuously separating a two-phase liquid consisting of at least two components that are completely immiscible with each other and separate into two phases, a light liquid and a heavy liquid, comprising:
continuously introducing the two-phase liquid into a chamber having an inlet on one side and a light liquid outlet and a heavy liquid outlet at the same height on the other side;
Between the inflow port and both the outflow ports, two meshes are installed with the vertical interval gradually decreasing from the upstream side to the downstream side to suppress permeation of heavy liquids and permeate floating light liquids. separating the two-phase liquid into upper and lower layers by a plate;
Together with the two mesh plates, a Y-shaped cross section is formed, and the interface between the upper and lower two layers is fixed by an upper and lower layer separator having the same height as the both discharge ports,
A continuous liquid-liquid separation method, wherein a light liquid and a heavy liquid are discharged from the light liquid discharge port and the heavy liquid discharge port, respectively.

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