Apparatus for producing concentrated liquid

Abstract

To provide a production method for efficiently obtaining a concentrated liquid in which a volatile component is concentrated.SOLUTION: The production method of the present invention includes an introduction step of introducing a gas phase containing a volatile component into a liquid phase composed of a hardly volatile or nonvolatile solvent. As a result, a concentrated liquid in which the volatile component is dissolved in the solvent is obtained. The production method of the present invention is carried out, for example, using a production apparatus including a container (11) for containing a liquid phase composed of a solvent (s), an air supply pipe (22) for guiding a gas phase containing a volatile component to the liquid phase, an exhaust pipe (32) for guiding the gas phase that has passed through the liquid phase to the outside of the container, and a pneumatic means (31) for circulating the gas phase from the air supply pipe to the exhaust pipe. When air bubbles are generated during the introduction step, a defoaming means (13) may be provided between the air supply pipe and the exhaust pipe.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present invention relates to a method for producing a solution (concentrated liquid) in which volatile components (such as odor components) are concentrated. [Background technology]

[0002] Volatile components (volatile substances) contained in the gas phase, such as the atmosphere, are generally collected by a solid-phase adsorbent. Analysis of the volatile components is usually performed by introducing the volatile components desorbed from the solid-phase adsorbent into a gas chromatograph (GC) or the like. Related descriptions can be found, for example, in the following non-patent literature: [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] Plant Protection, 2002, Vol.56, No.9, p.396-400. Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional methods for collecting (concentrating) volatile components limit the uses of the volatile components and make it difficult to store them for long periods of time.

[0005] The present invention has been made in view of the above circumstances, and has as its object to provide a new method for concentrating volatile components. [Means for solving the problem]

[0006] As a result of intensive research aimed at solving this problem, the inventors have discovered that volatile components can be collected as a concentrated liquid by using a solvent that is difficult to volatilize. By expanding on this finding, the present inventors have completed the present invention, which will be described below.

[0007] <<Method for producing concentrated liquid>> (1) The present invention is a production method comprising an introduction step of introducing a gas phase containing a volatile component into a liquid phase consisting of a low-volatility or non-volatile solvent, thereby obtaining a concentrated liquid in which the volatile component is dissolved in the solvent.

[0008] (2) According to the manufacturing method of the present invention, a concentrated solution can be efficiently obtained by dissolving volatile components in a solvent. This concentrated solution can be used to supply volatile components in a liquid state for various experiments and tests. Furthermore, since the solvent, which is difficult to volatilize, serves as an absorption liquid (adsorption liquid, preservation liquid) for the volatile components, the concentrated volatile components can be stored for a long period of time. Such concentrated solutions can be used in various products, thereby expanding the applications of volatile components.

[0009] <Concentrated liquid manufacturing device> The present invention can also be understood as an apparatus for producing a concentrated liquid. For example, the present invention may be an apparatus for producing a concentrated liquid comprising a container for containing a liquid phase made of a low-volatility or non-volatile solvent, an air inlet pipe for introducing a gas phase containing volatile components into the liquid phase, an exhaust pipe for introducing the gas phase that has passed through the liquid phase to the outside of the container, and a pneumatic conveying means for circulating the gas phase from the air inlet pipe to the exhaust pipe. The above-mentioned production method is carried out, for example, by such a production apparatus.

[0010] 《Concentrate》 The present invention can also be understood as a concentrated liquid obtained by the above-described production method or production apparatus. For example, the present invention may be a concentrated liquid comprising a solvent and a volatile component dissolved in the solvent, in which the volatile component is concentrated more than in the gas phase.

[0011] "others" Unless otherwise specified, "x to y" in this specification includes a lower limit of x and an upper limit of y. Any numerical value included in the various numerical values ​​or numerical ranges described in this specification can be used as a new lower limit or upper limit to create a new range such as "a to b." [Brief explanation of the drawings]

[0012] [Figure 1A] FIG. 1 is a schematic diagram showing an example of a concentrated liquid production apparatus. [Figure 1B]FIG. 10 is a schematic diagram showing another example of a concentrated liquid production apparatus. [Figure 2] This is a bar graph comparing the similarity of scents. [Figure 3] 1 is a bar graph comparing the extraction rates of volatile components into solvents. DETAILED DESCRIPTION OF THE INVENTION

[0013] One or more components selected from the present specification may be added to the above-described components of the present invention.Which embodiment is best depends on the target, required performance, etc.

[0014] 《Liquid phase》 The liquid phase (absorption liquid, adsorption liquid) that dissolves the volatile components may be made of a solvent that is less volatile than the volatile components, or even non-volatile. Although it is not necessary to strictly distinguish between non-volatile and non-volatile, for example, a solvent whose vapor pressure at room temperature (20°C) is less than 1 mmHg may be considered non-volatile, and a solvent whose vapor pressure is 1 mmHg or more may be considered non-volatile.

[0015] The liquid phase may contain a single solvent, or multiple solvents. Depending on the specifications of the concentrated liquid and the type of volatile components, the liquid phase may contain substances other than the solvent (additives, impurities, etc.).

[0016] The degree of volatility is indicated, for example, by boiling point, vapor pressure, etc. The higher the boiling point or the lower the vapor pressure, the lower the volatility. Note that, in this specification, the boiling point is the temperature under atmospheric pressure, and the vapor pressure is the saturated vapor pressure at room temperature (20°C).

[0017] The solvent may have a boiling point (Tb) of, for example, 150°C or higher, 180°C or higher, 200°C or higher, or even 250°C or higher. Examples of such solvents include various oils, such as mineral oil (Tb: 260-330°C), propylene glycol (Tb: 188°C), dipropylene glycol (Tb: 230°C), triethyl citrate (Tb: 294°C), jojoba oil (Tb: 380-430°C), squalane (Tb: 275°C), macadamia nut oil (Tb: 250°C or higher), sweet almond oil (Tb: 270°C or higher), olive oil (Tb: 298°C or higher), and hybrid safflower oil (Tb: 250°C or higher). Alternatively, the solvent may be an ionic liquid with a boiling point of 150°C or higher. The specific boiling point of the ionic liquid can be adjusted depending on the composition.

[0018] Such solvents can dissolve various volatile components with different molecular structures, molecular weights, etc. However, the extraction rate of the volatile component may vary depending on the compatibility between the solvent and the volatile component. Therefore, it is recommended to select an appropriate solvent depending on the volatile component to be collected, concentrated, etc. For example, for nonpolar volatile components (e.g., hydrocarbons / paraffins, olefins, etc. with 5 or more carbon atoms), it is recommended to use a liquid phase containing mineral oil rather than a liquid phase consisting solely of propylene glycol or dipropylene glycol. Conversely, for low-molecular-weight polar volatile components (e.g., alcohols with 5 or less carbon atoms), it is recommended to use a liquid phase containing other types of solvents rather than a liquid phase consisting solely of mineral oil, etc.

[0019] <Volatile components> The type of volatile component to be concentrated is not important. The source or supply source of the volatile component (referred to as the "volatile component source") is also not important. The volatile component may be recovered (captured) directly from various atmospheres, or may be supplied by desorbing the volatile component from an adsorbent that already contains the volatile component.

[0020] Representative volatile components are various odor components, such as citral, dihydrojasmonate, cinnamaldehyde, terpineol, terpinene, octanol, limonene, pinene, hexenol, leaf alcohol, hexenal, and isomers thereof.

[0021] 《Introduction process》 A concentrated liquid of volatile components can be obtained by introducing a gas phase containing volatile components into a liquid phase consisting of a solvent. The gas can be introduced into the liquid phase by suction from the downstream side of the liquid phase, or by pressure feeding from the upstream side of the liquid phase. The flow rate can be measured and controlled.

[0022] As long as the volatile components can be introduced into the liquid phase without altering their quality, the source of the volatile components, their temperature, the type of carrier gas (main component of the gas phase), etc. are not important. The carrier gas may be an atmospheric gas containing the volatile components. The use of an inert gas (nitrogen, argon, etc.) can prevent deterioration or alteration of the volatile components. Furthermore, if the concentrated liquid is kept in an inert gas atmosphere, it can be stored for a long period of time. In this specification, unless confusion occurs, the term "gas phase" will be used to refer to not only the gas before the liquid phase passes, but also the gas after the liquid phase passes.

[0023] Introduction of the gas phase into the liquid phase may cause foaming. The presence or absence of foaming and the degree of foaming depend on the type of solvent, introduction conditions, etc. Active bubbling may be used to promote contact between the volatile components and the liquid phase, thereby improving the concentration efficiency (extraction rate). However, when foaming occurs, it is recommended that defoaming be performed at the same time to prevent leakage of the concentrated liquid downstream.

[0024] 《Manufacturing equipment》 The manufacturing apparatus includes at least a container for containing a liquid phase containing a solvent, an air intake pipe for introducing a gas phase containing a volatile component into the liquid phase, an exhaust pipe for introducing the gas phase out of the container, and a gas conveying means for circulating the gas phase from the air intake pipe to the exhaust pipe.

[0025] The container may be used as a storage container for the concentrated liquid after the introducing step. In this case, it is preferable to close the opening of the container with a lid to seal in the concentrated liquid, inert gas, etc. The air transport means is realized, for example, by providing an air intake pump (exhaust pump, vacuum pump, etc.) downstream of the exhaust pipe.

[0026] A defoaming means for eliminating bubbles in the solvent may be provided between the air inlet pipe and the exhaust pipe (particularly inside the container). The defoaming means allows for recovery of the concentrated liquid (prevents leakage). If an air intake pump is provided downstream, the defoaming means also serves to protect the air intake pump. The defoaming means is, for example, a breathable porous body, a spongy body, a partition body, etc. The porous body is, for example, one or more punched sheets having a large number of openings (for example, hole diameter (maximum length): 0.1 to 1 mm). The spongy body is, for example, glass wool, sponge, etc. The partition body is, for example, one or more resistance plates arranged at predetermined intervals.

[0027] When an adsorbent is used as the source of volatile components, it is preferable to provide a desorption means for desorbing the volatile components from the adsorbent. The desorption means may be a gas supply means for pressure-feeding an inert gas or the like from the upstream side, or a temperature adjustment means for controlling the desorption of the volatile components by adjusting the temperature of the adsorbent, or these may be provided in parallel.

[0028] The temperature adjustment means preferably includes at least a heater for heating the adsorbent or the collection tube containing the adsorbent. To prevent the adsorbent from overheating, the temperature adjustment means may be provided with a sliding mechanism for moving the heater away from the adsorbent or the collection tube, a cooling mechanism (e.g., a blower fan, air supply means) for lowering the temperature of the adsorbent or the collection tube, etc. The temperature adjustment means may further be capable of controlling heating and cooling (heating and cooling) to maintain the adsorbent or the like at a set temperature.

[0029] Examples of adsorbents that can be used include porous polymer beads (Tenax TA, Tenax GR, etc.), carbon-based adsorbents (carbon molecular sieves, graphite carbon, coconut shell activated carbon, etc.), and metal-organic frameworks (MOFs).

[0030] A humidity adjusting means may be provided that can humidify or dry the gas phase to be introduced into the liquid phase. The humidity adjusting means may be, for example, disposed upstream of the adsorbent or the like and adjust the humidity of the carrier gas (inert gas or the like).

[0031] 《Concentrate》 The concentrate can be used for any purpose, including cell experiments, aromatherapy, (fragrant) skin care products (cosmetics, etc.), perfumes, and analysis of their ingredients. [Example]

[0032] An apparatus for introducing volatile components into a solvent was fabricated, and a concentrated solution of the volatile components was produced using the apparatus. The present invention will be described in more detail based on this specific example.

[0033] <Concentrated liquid manufacturing device> [First Example] An overview of the concentrated liquid manufacturing apparatus S1 (simply referred to as "apparatus D1") is shown in Figure 1A. Apparatus D1 includes an introduction section 1, an air intake section 2, and an exhaust section 3. The arrows in the figure indicate the up-down direction or the left-right direction. The air intake section 2 side is referred to as the upstream side, and the exhaust section 3 side is referred to as the downstream side.

[0034] Introduction section 1 includes container 11, lid 12, and defoamer 13. For example, a screw-cap test tube (container) may be used for container 11 and lid 12. For example, a punched sheet may be used for defoamer 13. The punched sheet is held in container 11 by being inserted into air supply pipe 22 (42), for example.

[0035] The gas supply unit 2 includes a gas supply valve 21 that adjusts the amount of carrier gas supplied, and a gas supply pipe 22 that connects the carrier gas (gas phase) containing volatile components to the solvent s held at the bottom of the container 11.

[0036] The exhaust unit 3 includes an exhaust pump 31 and an exhaust pipe 32 that connects the inside of the container 11 with the exhaust pump 31. The gas phase (head gas) in the upper part of the container 11 is exhausted to the outside by the exhaust pump 31 via the exhaust pipe 32. The exhaust pump 31 is preferably capable of adjusting the exhaust volume (adjusting the flow rate of the gas phase). The air supply pipe 22 and the exhaust pipe 32 are kept airtight by a lid 12 that closes the opening of the container 11.

[0037] [Second Example] An outline of a concentrated liquid production apparatus S2 (simply referred to as "apparatus D2") is shown in FIG. 1B. In apparatus D2, the air intake section 2 of apparatus D1 is replaced with an air intake section 4. The same components as those in apparatus D1 are denoted by the same reference numerals in FIG. 1B, and their explanation will be omitted.

[0038] The gas supply section 4 is equipped with a temperature controller 41 (detachment means) capable of accommodating a collection tube 5 filled with an adsorbent, and an air supply pipe 42 that connects the temperature controller 41 to the solvent s held at the bottom of the vessel 11. The temperature controller 41 is equipped with a heater and can adjust the temperature of the collection tube 5. The temperature controller 41 can be slid left and right to switch between storing and removing the collection tube 5, heating and cooling, etc. A carrier gas is introduced into the adsorbent.

[0039] <Production and evaluation of concentrated solution> [First test example] (1)Manufacturing A concentrated solution of volatile components was produced using apparatus D1. Specifically, the procedure is as follows: Mineral oil (Sigma Aldrich, boiling point 218-800°C) was used as solvent s. Cypress essential oil or tea tree essential oil was used as the volatile component source. A midget impinger with an inner diameter of φ28 mm and a length of 170 mm was used for container 11 and lid 12. A PTFE punched sheet (AS ONE Corporation, 1-6201-07) was used for defoamer 13. PTFE tubing (inner diameter φ1.58 mm) was used for air inlet pipe 22 and exhaust pipe 32. Nitrogen gas was used as the carrier gas. An MP-Σ100 model manufactured by Shibata Scientific Co., Ltd. was used for exhaust pump 31.

[0040] 5 mL of mineral oil was poured into the test tube. The downstream end of the air inlet pipe 22 was immersed in the mineral oil. The upstream end of the air inlet pipe 22 was placed inside the test tube (the upper part was open to the atmosphere) into which each essential oil had been dropped. The upstream end of the exhaust pipe 32 was placed at the top of the punching sheet inside the midget impinger. The downstream end of the exhaust pipe 32 was connected to the exhaust pump 31. The exhaust rate of the exhaust pump 31 was set to 0.3 L / min.

[0041] The exhaust pump 31 was operated for 8 hours (concentration time). In this way, the aroma (volatile components) of each essential oil was introduced into the mineral oil (introduction process), and each concentrated solution was obtained. After concentration was completed, the air intake valve 21 (three-way valve) installed in the air intake pipe 22 was switched to allow nitrogen gas (100 mL / min) to flow for 30 seconds.

[0042] (2) Evaluation Each concentrate was subjectively evaluated by an eight-person olfactory evaluation panel. Specifically, the degree of similarity between the scent of the concentrate and the actual scent (cypress, tea tree) was evaluated. For comparison, the degree of similarity between the scent of the main components contained in each essential oil (cypress: α-pinene, tea tree: terpinen-4-ol) and the actual scent was also evaluated. The results are summarized in Figure 2. The degree of similarity was determined using a visual analog scale with two endpoints: "not at all similar" and "smells exactly like the original."

[0043] As is clear from Figure 2, all of the concentrated solutions were closer to the original scent than the main components, confirming that the scent components of each essential oil could be efficiently concentrated.

[0044] [Second test example] (1)Manufacturing A concentrated liquid of volatile components was produced using the apparatus D2. Specifically, the procedure is as follows. Note that explanations common to the first test example are omitted.

[0045] In addition to the mineral oil mentioned above, water (purified water) was also prepared as the solvent s. The source of volatile components was an organic adsorbent (TENAX-TA) containing the 11 components shown in Figure 3. The container 11 and lid 12 were screw-cap test tubes with an inner diameter of 7.8 mm and a length of 100 mm.

[0046] The collection tube 5 filled with adsorbent (Tenax-TA 200 mg) was housed in a thermostat 41. The thermostat 41 was constructed by connecting a temperature controller to a cartridge heater built into an aluminum block. The upstream end of an air intake pipe 42 (similar to air intake pipe 22) was connected to the outlet of the collection tube 5. The temperature of the collection tube 5 was maintained at 280°C (constant) by the thermostat 41, and the volatile components were desorbed from each adsorbent.

[0047] The introduction step was carried out for each volatile component under the following conditions: nitrogen gas supply rate: 100 mL / min, exhaust rate of exhaust pump 31: 20 mL / min, and concentration time: 10 minutes.

[0048] (2) Evaluation The amount of volatile components collected when solvent s was added to container 11 was compared with the amount of volatile components collected when solvent s was not added to container 11, and the extraction rate (concentration efficiency) of each volatile component was determined. The results are summarized in Figure 3. The volatile components introduced into container 11 were collected using a separate collection tube (Tenax-TA) installed in the exhaust pipe 32.

[0049] As is clear from Figure 3, when low-volatility mineral oil was used as the solvent, the extraction rate of all volatile components was over 70%, and the volatile components were highly concentrated. On the other hand, when volatile water was used as the solvent, the extraction rate was generally low, although it varied depending on the volatile component. Furthermore, there were several volatile components that were hardly extracted (concentrated) in water.

[0050] From the above, it was confirmed that according to the present invention, a concentrated solution of volatile components can be efficiently obtained. [Explanation of symbols]

[0051] D1, D2 manufacturing equipment 1 Introduction 2 Air supply section 3 Exhaust section s Solvent

Claims

1. a vessel for containing a liquid phase comprising a hardly volatile or non-volatile solvent; an air supply pipe for introducing a gas phase containing volatile components into the liquid phase; an exhaust pipe for guiding the gas phase that has passed through the liquid phase to the outside of the container; a gas conveying means for circulating the gas phase from the intake pipe to the exhaust pipe, A manufacturing apparatus for obtaining a concentrated liquid in which the volatile components are dissolved in the solvent.

2. 2. The concentrated liquid manufacturing apparatus according to claim 1, further comprising a defoaming means between the air supply pipe and the exhaust pipe for eliminating bubbles in the solvent.

3. 3. The apparatus for producing a concentrated liquid according to claim 1, further comprising a desorption means for desorbing the volatile components from the adsorbent.

4. 4. The apparatus for producing a concentrated liquid according to claim 3, wherein the desorption means is a temperature adjustment means for the adsorbent.

5. 3. The concentrated liquid manufacturing apparatus according to claim 1, wherein the air transport means includes at least an air intake pump downstream of the exhaust pipe.

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