Penetration element, penetration apparatus, and penetration method using the penetration element

Abstract

To provide a permeation element capable of easily controlling the permeation of a solvent.SOLUTION: In a permeation element provided with a first electrode layer and a second electrode layer oppositely disposed in a separated state and a solution disposed between the first electrode layer and the second electrode layer,: the first electrode layer is formed with a conductive porous material; and a solvent in the solution is leached outside via the first electrode layer when applying an electric field between the first electrode layer and the second electrode layer.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a permeation element, a permeation device, and a permeation method using the permeation element.

Background Art

[0002] Conventionally, permeation devices using a porous filter or the like to separate a solvent in a solution have been known. Examples of such devices include devices using a reverse osmosis membrane (for example, Patent Document 1, etc.). Here, when using a reverse osmosis membrane, usually, pressure is utilized to reverse-permeate the solvent in the solution.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, the development of further technologies that can easily control the permeation of solvents has been desired.

Means for Solving the Problems

[0005] In view of the above, the present inventor has attempted to develop further technologies. Then, the present inventor newly found that for an element having a layer formed of a conductive porous material, by appropriately operating the applied electric field, the permeation of the solvent contained in the solution in contact with this layer can be easily controlled, and thus completed the present invention.

[0006] In other words, the present invention aims to advantageously solve the above problems, and the first embodiment of the present invention is a permeation element comprising (1) a first electrode layer and a second electrode layer arranged opposite each other at a distance from each other, and a solution disposed between the first electrode layer and the second electrode layer, wherein the first electrode layer is formed of a conductive porous material, and when an electric field is applied between the first electrode layer and the second electrode layer, the solvent in the solution leaches out to the outside through the first electrode layer. With such a permeation element, the permeation of the solvent can be easily controlled by appropriately manipulating the applied electric field.

[0007] (2) In the permeation element described in (1) above, the first electrode layer is preferably a cathode layer. If the first electrode layer is a cathode layer, the amount of solvent leached out can be improved.

[0008] (3) In the permeation element of (1) or (2) above, it is preferable that the conductive porous material contains a carbon material. If the conductive porous material contains a carbon material, the amount of solvent leached out can be improved.

[0009] (4) In the permeation element described in (3) above, it is preferable that the carbon material includes nanocarbon material. If the carbon material includes nanocarbon material, the amount of solvent leached out can be further improved.

[0010] (5) In the permeation element described in (4) above, it is preferable that the nanocarbon material contains carbon nanotubes. If the nanocarbon material contains carbon nanotubes, the amount of solvent leached out can be further improved.

[0011] (6) In the permeation element described in (5) above, it is preferable that the carbon nanotubes include single-walled carbon nanotubes. If the carbon nanotubes include single-walled carbon nanotubes, the amount of solvent leached out can be further improved.

[0012] (7) In any of the permeation elements described in (1) to (6) above, the first electrode layer is preferably a sheet-like structure. If the first electrode layer is a sheet-like structure, the conductivity and porosity of the first electrode layer can be maintained well. In addition, if the first electrode layer is a sheet-like structure, the permeation element can be easily manufactured.

[0013] (8) In the penetrating element described in (7) above, it is preferable that the sheet-like structure does not contain a binder. If the sheet-like structure does not contain a binder, the internal resistance of the sheet-like structure can be reduced. In this specification, "binder-free" means that no binder components are detected when the binder content is measured using analytical methods such as mass spectrometry chromatography.

[0014] Furthermore, this invention aims to advantageously solve the above problems, and a second embodiment of the present invention is a permeation element comprising (9) a conductive porous material layer formed of a conductive porous material, a first electrode formed on one surface of the conductive porous material layer, a second electrode formed on the other surface of the conductive porous material layer, and a solution disposed on the other side of the conductive porous material layer, wherein when an electric field is applied between the first electrode and the second electrode with the solution in contact with the second electrode, the solvent in the solution leaches out toward the first electrode through the conductive porous material layer. With such a permeation element, the permeation of the solvent can be easily controlled by appropriately manipulating the applied electric field.

[0015] (10) In the permeation element described in (9) above, the first electrode is preferably a cathode. If the first electrode is a cathode, the amount of solvent leached out can be improved.

[0016] (11) In the permeation element of (9) or (10) above, it is preferable that the conductive porous material contains a nanocarbon material. If the conductive porous material contains a nanocarbon material, the amount of solvent permeation from the conductive porous material layer can be further improved.

[0017] (12) In any of the permeation elements (9) to (11) above, the conductive porous material layer is preferably a sheet-like structure. If the conductive porous material layer is a sheet-like structure, the conductivity and porosity of the conductive porous material layer can be kept good. If the conductive porous material layer is a sheet-like structure, the permeation element can be easily manufactured.

[0018] Moreover, the present invention aims to advantageously solve the above problems, and the present invention is a permeation device comprising (13) any of the permeation elements (1) to (12) above and a DC power source. With such a permeation device, the permeation of the solvent can be easily controlled by appropriately operating the applied electric field.

[0019] Moreover, the present invention aims to advantageously solve the above problems, and the present invention is a permeation method using any of the permeation elements (1) to (12) above, and is a permeation method in which an electric field is applied to the first electrode layer and the second electrode layer, or the first electrode and the second electrode. With such a permeation method, the solvent in the solution can be leached from the layer formed of the conductive porous material.

Effect of the Invention

[0020] According to the present invention, a permeation element capable of easily controlling the permeation of a solvent can be provided. Moreover, according to the present invention, a permeation device provided with the above permeation element can be provided. Moreover, according to the present invention, a permeation method using the above permeation element can be provided.

Brief Description of the Drawings

[0021] [Figure 1] It is a schematic cross-sectional view showing an example of the permeation element of the first form of the present invention. [Figure 2] It is a schematic cross-sectional view showing an example of the use of the permeation element shown in FIG. 1. [Figure 3] It is a schematic cross-sectional view showing an example of the permeation element of the second form of the present invention. [Figure 4]Figure 3 is a schematic cross-sectional view showing an example of the use of the permeation element. [Figure 5] This is a schematic cross-sectional view showing the test specimen of Example 1. [Figure 6] This is a schematic cross-sectional view showing the test specimen of Example 4. [Figure 7] Figure 6 is a top view of the test specimen. [Modes for carrying out the invention]

[0022] Embodiments of the present invention will be described in detail below. Herein, the permeation element of the present invention allows for easy control of the permeation of a solvent contained in a solution in contact with a layer formed of a conductive porous material by appropriately manipulating the applied electric field (switching on and off, switching between positive and negative, changing the electric field value, etc.), thereby enabling the acquisition or removal of a specific solvent at a desired timing and / or amount. For this reason, the permeation element of the present invention can be suitably used in permeation devices such as desalination devices for saltwater such as seawater, water purification devices for removing impurities from water, and separation devices for extracting a specific solvent from a complex solvent. Furthermore, it can be suitably used in permeation devices such as concentration devices for removing solvents from solutions containing proteins, nucleic acids (DNA, RNA), etc., in the field of biotechnology. However, the applications of the permeation element are not limited to these.

[0023] (First form of penetrating element) The first embodiment of the permeation element comprises a first electrode layer and a second electrode layer arranged opposite each other at a distance from each other, and a solution placed between the first and second electrode layers, wherein the first electrode layer is formed of a conductive porous material. In the first embodiment of the permeation element, when an electric field is applied between the first and second electrode layers, the solvent in the solution leaches out to the outside through the first electrode layer. With the above-mentioned permeation element, solvent penetration can be easily controlled by appropriately manipulating the applied electric field. The reason for this is not entirely clear, but it is presumed that free electrons and holes in the conductive porous material move due to electrons supplied by the applied electric field, changing the interaction between the conductive porous material and the solvent, and as a result, solvent molecules are attracted towards the conductive porous material.

[0024] Figure 1 is a schematic cross-sectional view showing an example of a first embodiment of the present invention. The first embodiment of the permeation element 10, as shown in Figure 1, comprises a first electrode layer 11 and a second electrode layer 12 arranged opposite each other at a distance from each other, and a solution 13 placed between the first electrode layer 11 and the second electrode layer 12. Here, the first electrode layer 11 has a first surface 111 that is in contact with the solution 13, and a second surface 112 that is located on the opposite side from the first surface 111.

[0025] Although not shown in Figure 1, the permeation element 10 may include a sealing member such as a sealing plate or a cylinder. The sealing member may be provided liquid-tight on one surface of the first electrode layer 11 or the second electrode layer 12, or it may be provided to liquid-tightly seal the side surface of the first electrode layer 11 or the second electrode layer 12. Although not shown in Figure 1, the permeation element 10 may further include a separator between the first electrode layer 11 and the second electrode layer 12. Including such a separator allows for maintaining an appropriate distance between the first electrode layer 11 and the second electrode layer 12. Furthermore, solution 13 may be left to stand or stirred using a stirrer, screwdriver, or the like.

[0026] Figure 2 is a schematic cross-sectional view showing an example of the use of the permeation element shown in Figure 1. As shown in Figure 2, the first electrode layer 11 is connected to the negative electrode of the DC power supply E by wiring W, and the second electrode layer 12 is connected to the positive electrode of the DC power supply E by wiring W. When an electric field is applied between the first electrode layer 11 and the second electrode layer 12, the solvent in the solution 13 can leach out through the first electrode layer 11 (leachation from the first surface 111 to the second surface 112). In Figure 2, the first electrode layer 11 is connected to the negative electrode and the second electrode layer 12 is connected to the positive electrode, but the first electrode layer 11 may be connected to the positive electrode and the second electrode layer 12 to the negative electrode.

[0027] <First electrode layer> In the first embodiment of the penetrating element, the first electrode layer is a layer formed of a conductive porous material, that is, a layer having conductivity and porous properties, and is substantially impermeable to the solvent when no electric field is applied. Here, the conductive porous material is not particularly limited as long as it is conductive, and may be a conductor, a semiconductor, or a combination thereof. The first electrode layer preferably contains a conductor and a semiconductor as the conductive porous material because it can improve the amount of solvent leaching. Here, "including conductors and semiconductors" means both including materials that have the properties of a conductor and materials that have the properties of a semiconductor, and including materials that have both the properties of a conductor and a semiconductor. The first electrode layer may be either a cathode layer or an anode layer, but it is preferable to be a cathode layer because it can improve the amount of solvent leached out.

[0028] Examples of conductive porous materials include metals and / or metal-containing materials such as silver, copper, gold, aluminum, magnesium, zinc, nickel, platinum, tin, titanium, stainless steel, zinc oxide, magnesium oxide, silicon, germanium, and oxides of these metals; and carbon materials such as nanocarbon materials, graphene, fullerene, graphite, activated carbon, carbon fiber, expanded graphite, and carbon black. Examples of nanocarbon materials include carbon nanotubes, graphene sheets, carbon nanohorns, and nanographene. The above-mentioned conductive porous material may be used alone or in combination of two or more types.

[0029] The conductive porous material preferably contains carbon material. Carbon material has excellent conductivity and can maintain good porosity of the first electrode layer; therefore, if the conductive porous material contains carbon material, the amount of solvent leaching can be improved. Furthermore, it is preferable that the carbon material includes nanocarbon material. If the carbon material includes nanocarbon material, the specific surface area of ​​the first electrode layer increases, the contact area between the first electrode layer and the solvent increases, and the amount of solvent leached out can be further improved. Furthermore, it is preferable that the nanocarbon material contains carbon nanotubes (hereinafter also referred to as "CNTs"). If the nanocarbon material contains CNTs, the amount of solvent leaching can be further improved. The reason for this is not entirely clear, but it is presumed that CNTs possess both conductive and semiconductor properties well. Examples of such a first electrode layer containing CNTs include a CNT film, which is sometimes called "bucky paper," formed by assembling multiple CNTs into a film.

[0030] Here, CNTs are nanocarbon materials having a structure in which graphene sheets are wound into a cylindrical shape, and are broadly classified into single-walled CNTs and multi-walled CNTs based on the number of components in their peripheral walls. Single-walled CNTs are preferred because even with a small amount of CNTs added, the specific surface area of ​​the first electrode layer becomes large, further increasing the contact area between the first electrode layer and the solvent, and as a result, the amount of solvent leaching can be further improved.

[0031] The average diameter of the CNTs is preferably 0.5 nm or more, more preferably 1 nm or more, preferably 15 nm or less, and more preferably 10 nm or less. If the average diameter of the CNTs is within the above range, the surface area of ​​the first electrode layer will increase, the contact area between the first electrode layer and the solvent will increase, and as a result, the amount of solvent leached out can be further improved.

[0032] It is preferable that the mean diameter (Av) and the standard deviation of the diameter (3σ) of the CNT satisfy the relationship: 0.60 > "3σ / Av" > 0.20. Here, "mean diameter (Av)" and "diameter distribution (3σ)" refer to the average value and standard deviation (σ) obtained by multiplying by 3, respectively, when the diameters (outer diameters) of 100 randomly selected CNTs are measured using a transmission electron microscope. Note that the standard deviation in this specification is the sample standard deviation. By using CNTs that satisfy the above relationship, the flexibility of the first electrode layer can be improved. CNTs that satisfy the above relationship can be produced by changing the manufacturing method or conditions of CNTs, or by combining multiple types of CNTs obtained by different manufacturing methods.

[0033] The BET specific surface area of ​​CNT is 600m². 2 It is preferable that it be 1 / g or more, and 800m 2 It is more preferable that it be 1000m or more per gram. 2 It is even more preferable that the amount be 1 / g or more. If the BET specific surface area of ​​the CNTs is above the lower limit mentioned above, the flexibility of the first electrode layer can be improved. Furthermore, if the BET specific surface area of ​​the CNTs is above the lower limit mentioned above, the contact area between the first electrode layer and the solvent increases, and as a result, the amount of solvent leaching can be further improved. The BET specific surface area of ​​CNT is, for example, 2600 m². 2 It is less than / g and 2000m 2 It is also acceptable to use values ​​less than / g. In this specification, the BET specific surface area of ​​CNTs is the nitrogen adsorption specific surface area measured using the BET method. CNTs having the above BET specific surface area can be manufactured using methods such as the supergrowth method (see International Publication No. 2006 / 011655).

[0034] For CNTs, the ratio of the G-band peak intensity to the D-band peak intensity in the Raman spectrum (G / D ratio) is preferably 0.5 or higher, and preferably 5.0 or lower. CNTs having the above-mentioned band peaks can be produced using methods such as the supergrowth method (see International Publication No. 2006 / 011655).

[0035] The first electrode layer may be a composite of a conductive porous material and another material different from the conductive porous material (hereinafter also referred to as "other material"), to the extent that it does not impair the objective of the present invention. Examples of other materials include binders and ion-containing materials.

[0036] The binder is not particularly limited and can include common resins such as polystyrene and acrylic resin.

[0037] The ion-containing material is not particularly limited and includes, for example, anionic surfactants such as sodium dodecylsulfonate, sodium deoxycholate, sodium cholate, and sodium dodecylbenzenesulfonate, as well as cationic surfactants.

[0038] The method for forming the first electrode layer is not particularly limited, but examples include a method in which a conductive porous material, a dispersion medium, and optionally another material are mixed to prepare a dispersion, and the dispersion medium is removed from the dispersion by filtration or the like to form a sheet-like first electrode layer; or a method in which the above dispersion is prepared, applied to a substrate such as a separator, and dried to form a coating-like first electrode layer. The method for applying the dispersion is not particularly limited, but examples include spraying, printing, and dispensing. For the first electrode layer, it is preferable to use a sheet-like structure because it can maintain good conductivity and porosity of the first electrode layer. Furthermore, if the conductive porous material layer is a sheet-like structure, it becomes easier to handle, and the permeable element can be easily manufactured.

[0039] When the first electrode layer is a sheet-like structure, it is preferable that the sheet-like structure does not contain a binder. Since the resin used as a binder can improve internal resistance, if the sheet-like structure does not contain a binder, the internal resistance of the sheet-like structure can be reduced.

[0040] The dispersion medium for dispersing the conductive porous material is not particularly limited and includes, for example, water, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, and amyl alcohols; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; esters such as ethyl acetate and butyl acetate; ethers such as diethyl ether, dioxane, and tetrahydrofuran; amide-based polar organic dispersion media such as N,N-dimethylformamide and N-methylpyrrolidone (NMP); and aromatic hydrocarbons such as toluene, xylene, chlorobenzene, orthodichlorobenzene, and paradichlorobenzene. These may be used individually or in combination of two or more types.

[0041] The porosity of the first electrode layer is, for example, 60% or more, may be 65% or more, may be 70% or more, may be 90% or less, may be 85% or less, or may be 80% or less. The porosity of the first electrode layer can be determined, for example, by processing a cross-section of the first electrode layer with a focused ion beam (FIB), observing the cross-section with energy-dispersive X-ray spectroscopy (SEM-EDX), identifying the position of the C element in the SEM observation image from the obtained visualization image of the C element, calculating the occupancy rate (A) of the C element in the entire field of view, and then determining it using the following formula (1). Porosity (%)=100-A (1)

[0042] The thickness of the first electrode layer is, for example, 20 μm or more, may be 30 μm or more, may be 40 μm or more, and may be, for example, 120 μm or less, may be 90 μm or less, or may be 60 μm or less.

[0043] <Second electrode layer> In the first form of the permeation element, the second electrode layer is substantially impermeable to the solvent when no electric field is applied. The second electrode layer may be either an anode layer or a cathode layer. If the first electrode layer is a cathode layer, the second electrode layer is an anode layer, and conversely, if the first electrode layer is an anode layer, the second electrode layer is a cathode layer.

[0044] As the material for the second electrode layer, conventionally known materials can be used, such as the metals and / or metal-containing materials mentioned above, or carbon materials, as appropriate. Furthermore, the same electrode layer as the first electrode layer described above can also be used as the second electrode layer.

[0045] <Solution> In the first embodiment of the permeation element, the solution contains a solute and a solvent. The solvent is not particularly limited and includes, for example, water, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, amyl alcohol and other alcohols, acetone, methyl ethyl ketone and cyclohexanone and other ketones, ethyl acetate and butyl acetate and other esters, diethyl ether and dioxane and tetrahydrofuran and other amide-based polar organic solvents such as N,N-dimethylformamide and N-methylpyrrolidone (NMP). Among these, water is preferred. These solvents may be used individually or in combination of two or more. Examples of solutes include electrolytes such as sodium chloride and colorants such as dyes. These solutes may be used individually or in combination of two or more. It is preferable that the solute contains an electrolyte, as this can improve the amount of solvent leached out. In this specification, "solution" includes tap water, etc. Tap water may contain, for example, chlorine-based compounds.

[0046] <Separator> In the first form of the permeation element, the separator is used to maintain an appropriate distance between the first electrode layer and the second electrode layer when the solvent is located between the first electrode layer and the second electrode layer.

[0047] The separator preferably has a porous structure. If the separator is porous, the solution can be impregnated well into the separator, and as a result, the solution can be uniformly dispersed between the first electrode layer and the second electrode layer.

[0048] Examples of separators that can be used include microporous membranes or nonwoven fabrics made of resins containing polyolefin resins such as polyethylene and polypropylene, or aromatic polyamide resins; porous resin coatings containing inorganic ceramic powder; paper; polymer gels, etc. Specific examples include microporous membranes made of resins such as polyolefins (polyethylene, polypropylene, polybutene, polyvinyl chloride) and mixtures or copolymers thereof; microporous membranes made of resins such as polyethylene terephthalate, polycycloolefin, polyethersulfone, nylon, polyamides, polyimides, polyimideamides, polyaramids, and polytetrafluoroethylenes; woven polyolefin fibers or nonwoven fabrics thereof; and aggregates of insulating material particles.

[0049] In one embodiment, the separator preferably contains an inorganic oxide material. If the separator contains an inorganic oxide material, it can adsorb products that may be generated in the solution by chemical reactions or the like when the permeation element is used.

[0050] The inorganic oxide material is not particularly limited, but examples include alumina (aluminum oxide), magnesia (magnesium oxide), silica (silicon oxide), titania (titanium oxide), and zirconia (zirconium oxide). These may be used individually or in combination of two or more. Among these, alumina is preferred due to its excellent adsorption performance.

[0051] The inorganic oxide material is preferably a fibrous structure. If the inorganic oxide material is a fibrous structure, it can better adsorb products that may be generated in the solution by chemical reactions during the use of the permeation element. Furthermore, if the inorganic oxide material is a fibrous structure, the separator can be impregnated with the solution well, and as a result, the solution can be uniformly dispersed between the first electrode layer and the second electrode layer. As a separator of inorganic oxide material with a fibrous structure, a fibrous sheet of the inorganic oxide material can be used.

[0052] The thickness of the separator is preferably 1 mm or less, and more preferably 0.7 mm or less.

[0053] (Second form of penetrating element) The second embodiment of the present invention is a permeation element comprising a conductive porous material layer formed of a conductive porous material, a first electrode formed on one surface of the conductive porous material layer, a second electrode formed on the other surface of the conductive porous material layer, and a solution disposed on the other side of the conductive porous material layer. In the second embodiment of the permeation element, when an electric field is applied between the first electrode and the second electrode with the solution in contact with the second electrode, preferably with the solution in contact with both the second electrode and the conductive porous material layer, the solvent in the solution leaches out towards the first electrode through the conductive porous material layer. With such a permeation element, the permeation of the solvent can be easily controlled by appropriately manipulating the applied electric field.

[0054] Figure 3 is a schematic cross-sectional view showing an example of a second embodiment of the present invention. As shown in Figure 3, the second embodiment of the permeation element 20 comprises a conductive porous material layer 21, a first electrode 22 formed on one surface of the conductive porous material layer 21, a second electrode 23 formed on the other surface of the conductive porous material layer 21, and a solution 24 disposed on the other side of the conductive porous material layer 21. Here, the conductive porous material layer 21 has a first surface 211 that is in contact with the solution 24, and a second surface 212 located on the opposite side of the first surface 211. That is, in the permeation element 20, the first electrode 22 is formed on the second surface 212, the second electrode 23 is formed on the first surface 211, and the solution 24 is disposed on the first surface 211 side. In Figure 3, there is one first electrode 22, but two or more first electrodes 22 may be used. Also, in Figure 3, there are two second electrodes 23, but one or three or more second electrodes 23 may be used.

[0055] Although not shown in Figure 3, the permeation element 20 may include a sealing member such as a sealing plate or a cylinder. The sealing member may be provided liquid-tight on one surface of the conductive porous material layer 21, or it may be provided to liquid-tightly seal the side surface of the conductive porous material layer 21. Furthermore, solution 24 may be left to stand or stirred using a stirrer, screwdriver, or the like.

[0056] Figure 4 is a schematic cross-sectional view showing an example of the use of the permeation element shown in Figure 3. As shown in Figure 4, the first electrode 22 is connected to the negative electrode of the DC power supply E by wiring W, and the second electrode 23 is connected to the positive electrode of the DC power supply E by wiring W. When an electric field is applied between the first electrode 22 and the second electrode 23, the solvent in the solution 24 can leach out toward the first electrode 22 (from the first surface 211 to the second surface 212) through the conductive porous material layer 21. In Figure 4, the first electrode 22 is connected to the negative electrode and the second electrode 23 is connected to the positive electrode, but the first electrode 22 may be connected to the positive electrode and the second electrode 24 to the negative electrode.

[0057] <Conductive porous material layer> In the second embodiment of the permeation element, the conductive porous material layer is a layer formed of a conductive porous material, that is, a layer having conductivity and porous properties, and is substantially impermeable to solvent when no electric field is applied. Here, the conductive porous material layer in the second embodiment of the permeation element can preferably be the same as the first electrode layer in the first embodiment of the permeation element. Details regarding conductive porous materials and other materials have been described above, so they will not be explained here.

[0058] <First electrode> In the second form of the permeation element, the first electrode may be either a cathode or an anode, but it is preferable to be a cathode because it can improve the amount of solvent leached out.

[0059] As the material for the first electrode, conventionally known materials can be used, such as the metals and / or metal-containing materials mentioned above, or carbon materials, as appropriate.

[0060] The shape of the first electrode is not particularly limited and can be various shapes such as rod-shaped, circular, ring-shaped, or sheet-shaped.

[0061] <Second electrode> In the second form of the penetrating element, the second electrode may be either an anode or a cathode. If the first electrode is a cathode, the second electrode is an anode; conversely, if the first electrode is an anode, the second electrode is a cathode.

[0062] As the material for the second electrode, conventionally known materials can be used, such as the metals and / or metal-containing materials mentioned above, or carbon materials, as appropriate.

[0063] The shape of the second electrode is not particularly limited and can be various shapes such as rod-shaped, circular, ring-shaped, or sheet-shaped.

[0064] In one embodiment of the permeation element, it is preferable that the second electrode is ring-shaped and the first electrode is provided within the inner circumference region of the ring via a conductive porous material layer (see, for example, Figures 6 and 7 described later). With such a permeation element, the penetration position of the solvent can be kept within the above range.

[0065] <Solution> In the second embodiment of the permeation element, the solution can preferably be the same as the solution used in the first embodiment of the permeation element. As details about the solution have been described above, we will omit further explanation here.

[0066] (Infiltration device) The permeation apparatus of the present invention comprises the permeation element of the present invention described above and a DC power supply. When an electric field is applied to the first electrode layer and the second electrode layer, or to the first electrode and the second electrode, by a DC power supply, the permeation apparatus of the present invention can cause the solvent in the solution to leach out through a layer formed of a conductive porous material. Since the permeation element of the present invention allows for easy control of solvent penetration by appropriately manipulating the applied electric field, the permeation apparatus of the present invention equipped with this element allows for easy control of solvent penetration by appropriately manipulating the applied electric field. A DC power supply is equipped with a positive electrode and a negative electrode, and conventionally known types can be used. The electrode layer or electrodes of the penetrating element are connected to the electrodes of the DC power supply by wiring. Conventional wiring can be used. Here, the devices shown in Figures 2 and 4 can be considered examples of the infiltration apparatus of the present invention.

[0067] (Infiltration method) The penetration method of the present invention uses the penetration element of the present invention described above. In the penetration method of the present invention, an electric field is applied to the first electrode layer and the second electrode layer, or to the first electrode and the second electrode. Since the penetration element of the present invention allows for easy control of solvent penetration by appropriately manipulating the applied electric field, the penetration method using it can cause the solvent in the solution to leach out from a layer formed of a conductive porous material.

[0068] The strength of the electric field is not particularly limited as long as it is the voltage at which the solvent penetrates the layer formed by the conductive porous material, but it is preferably 1V or more, more preferably 1.5V or more, preferably 5V or less, more preferably 3V or less, and even more preferably 2V or less. If the voltage is above the lower limit mentioned above, the amount of solvent leached out can be improved. On the other hand, if the voltage is below the upper limit mentioned above, the energy cost in the infiltration method of the present invention can be reduced. [Examples]

[0069] The present invention will be described in detail below based on examples, but the present invention is not limited to these examples. In the following description, "%" and "parts" used to express quantities refer to mass unless otherwise specified. In the examples, various measurements were performed according to the following methods.

[0070] <Measurement of porosity> The porosity of the sheet-like structures prepared in the examples was determined by the following procedure. First, the cross-section of the sheet-like structure was processed using a focused ion beam (FIB). Next, the cross-section was observed using energy-dispersive X-ray spectroscopy (SEM-EDX), and the position of the C element in the SEM observation image was identified from the obtained visualization image of the C element. Then, the occupancy rate (A) of the C element in the entire field of view was calculated, and the porosity (%) was determined using the following formula (1). Porosity (%)=100-A (1)

[0071] (Example 1) <Fabrication of sheet-like structures> CNT (manufactured by Zeon Technology Co., Ltd., ZEONANO®, SG101, BET specific surface area: 1,000 m²) 2100 parts of (1 / g or more) were mixed with 20,000 parts of ethanol as a dispersion medium and stirred. The resulting dispersion was filtered by suction using a membrane filter (Advantec Co., Ltd., product name: T010A090C, pore size: 0.1 μm, diameter: 90 mm). The filtrate obtained on the membrane filter was washed with 1 L of ethanol. After thoroughly drying the washed filtrate at room temperature, it was further dried using vacuum drying at 80°C for 2 hours to obtain a sheet-like structure formed from a conductive porous material with a thickness of 50 μm. The porosity of the obtained sheet-like structure was measured and found to be 75%.

[0072] <Preparation of test specimens> Next, the test specimen 30 shown in Figure 5 was prepared. Specifically, we first prepared two sheet-like structures cut to 30mm x 10mm (sheet-like structure A31 and sheet-like structure B33), a polyimide sheet 34 measuring 40mm x 30mm, and an alumina sheet 32 ​​measuring 30mm x 20mm x 0.5mm thick (manufactured by Tomoegawa Manufacturing Co., Ltd., alumina fiber paper) as a separator. Next, the upper vertical edges of the polyimide sheet 34 and the sheet-like structure B33 were aligned, and the horizontal centers of the polyimide sheet 34 and the sheet-like structure B33 were aligned, and the sheet-like structure B33 was fixed to the surface of the polyimide sheet 34 using double-sided tape (not shown). A margin of 10 mm in width (the portion consisting only of the polyimide sheet 34) remained at the lower vertical edge of the polyimide sheet 34. Next, the alumina sheet 32 ​​was fixed to the surface of the sheet-like structure B33 using double-sided tape (not shown), shifted 5 mm vertically from the upper end of the sheet-like structure B33 so that the horizontal centers of the sheet-like structure B33 and the alumina sheet 32 ​​overlapped. A margin of 5 mm in width (the portion consisting only of the polyimide sheet 34) remained at the lower vertical end of the polyimide sheet 34. Next, a polyimide tape 35 measuring 30 mm in length and 5 mm in width was applied in two layers, ensuring that it did not extend beyond the 5 mm margin, thereby reducing the height difference caused by the thickness of the sheet-like structure B33 and the alumina sheet 32. Next, the sheet-like structure A31 was fixed to the surface of the alumina sheet 32 ​​using double-sided tape (not shown) by shifting it 5 mm vertically from the upper edge of the alumina sheet 32 ​​(i.e., 10 mm vertically from the upper edge of the sheet-like structure B33) so that the horizontal centers of the alumina sheet 32 ​​and the sheet-like structure A31 overlapped. Next, a hole measuring 30 mm vertically and 20 mm horizontally was cut out from the center of the polyimide sheet 34 to create the test specimen 30 shown in Figure 5. In the sheet-like structure A31, the side facing the alumina sheet 32 ​​is the first surface 311, and the side opposite the alumina sheet 32 ​​is the second surface 312.

[0073] <Manufacturing of the first form of penetrating element> The alumina sheet 32 ​​of the test piece 30 prepared as described above was impregnated with tap water (solute: chlorine-based compound) as a solution to produce the first form of permeable element.

[0074] <Manufacturing of power generation equipment> Using wiring, the negative electrode of the DC power supply was connected to the sheet-like structure A31 (first electrode layer), and the positive electrode of the DC power supply was connected to the sheet-like structure B33 (second electrode layer), thereby manufacturing a permeation device.

[0075] <Penetration Test> When a DC voltage of 3V was applied to the sheet-like structures A31 and B33 of the impregnation apparatus using a DC power supply, water seeped out from sheet-like structure A31. On the other hand, almost no water seeped out from sheet-like structure B33. Next, the wiring was reconnected so that sheet-like structure B33 was connected to the negative terminal of the DC power supply and sheet-like structure A31 was connected to the positive terminal of the DC power supply. When a 3V DC voltage was applied again, water seeped out from sheet-like structure B33, but almost no water seeped out from sheet-like structure A31.

[0076] (Example 2) Except for changing the tap water to 0.3% by mass saline solution and changing the DC voltage to 1.5V, various operations and tests were performed in the same manner as in Example 1. Despite the penetration test result being lower than Example 1 at 1.5V, liquid vigorously seeped out from sheet-like structure A31. Analysis of this liquid using pH test paper and microscopic observation revealed that it was solely water. On the other hand, almost no liquid seeped out from sheet-like structure B33. Similar to Example 1, when the wiring was reconnected, liquid (water) vigorously seeped out from the sheet-like structure B33, but almost no liquid seeped out from the sheet-like structure A31.

[0077] (Example 3) Except for replacing tap water with an aqueous solution containing 1% water-soluble red dye, various operations and tests were carried out in the same manner as in Example 1. The penetration test showed that colorless, transparent water seeped out of sheet-like structure A31, but no red dye seeped out. On the other hand, almost no water seeped out of sheet-like structure B33, and no red dye seeped out either. Similar to Example 1, when the wiring was reconnected, colorless, transparent water seeped out from the sheet-like structure B33, but almost no water seeped out from the sheet-like structure A31, and no red dye seeped out either.

[0078] (Example 4) <Preparation of test specimens> Using the sheet-like structure prepared in Example 1, test specimens 40, as shown in Figures 6 and 7, were fabricated. Specifically, first, the sheet-like structure was cut to 100mm x 100mm (sheet-like structure 41). Next, silver paste was applied to the first surface 411 of the sheet-like structure 41 to form two ring-shaped silver electrodes B43 with an inner diameter of φ20 mm and a width of 1 mm. Next, silver paste was applied to the inner circumference region of the ring of the silver electrode B43 via the sheet-like structure 41 (on the second surface 412 side) to form two circular silver electrodes A42 with an outer diameter of φ2 mm, thereby creating the test specimen 40.

[0079] <Manufacturing of a second type of permeation element (permeation device)> First, the negative terminal of the DC power supply was connected to silver electrode A42 (first electrode), and the positive terminal of the DC power supply was connected to silver electrode B43 (second electrode), respectively, using wiring. Next, a cylinder with an inner diameter of φ50 mm was prepared, and a sheet-like structure 41 (conductive porous material layer) was attached to the open end of one side of the cylinder so that the two silver electrodes B43 would fit inside the cylinder. Next, the inside of the cylinder was filled with tap water to manufacture a second type of permeation element (permeation device).

[0080] <Penetration Test> When a DC voltage of 3V was applied to the silver electrodes A42 and B43 of the permeation apparatus using a DC power supply, water seeped out from within the inner circumference region of the ring of silver electrode B43 in the sheet-like structure 41. Next, the wiring was reconnected so that silver electrode B43 was connected to the negative terminal of the DC power supply and silver electrode A42 was connected to the positive terminal of the DC power supply, and a DC voltage of 3V was applied again. No water seeped out from the sheet-like structure 41.

[0081] As is clear from the results of the penetration tests in Examples 1 to 4 above, by using the penetration elements of Examples 1 to 4, it is possible to easily control the penetration of the solvent contained in the solution in contact with the layer formed by the conductive porous material by appropriately manipulating the applied electric field. [Industrial applicability]

[0082] According to the present invention, a permeation element can be provided that allows for easy control of solvent penetration. Furthermore, according to the present invention, a penetration device equipped with the above-mentioned penetration element can be provided. Furthermore, according to the present invention, a penetration method using the above-mentioned penetration element can be provided. [Explanation of Symbols]

[0083] 10: Penetrating element 11:First electrode layer 111: Front page 112:Second side 12:Second electrode layer 13: Solution 20: Penetration element 21: Conductive porous material layer 211: Front page 212:Second side 22:First electrode 23:Second electrode 24: Solution 30: Test specimen 31: Sheet-like structure A 311: Front page 312:Second side 32: Alumina sheet 33: Sheet-like structure B 34: Polyimide sheet 35: Polyimide Tape 40: Test specimen 41: Sheet-like structure 411: Front page 412:Second side 42: Silver electrode A 43: Silver electrode B E: DC power supply W: Wiring

Claims

1. A first electrode layer and a second electrode layer are positioned opposite each other in a separated state, A solution disposed between the first electrode layer and the second electrode layer, The first electrode layer is formed of a conductive porous material, The porosity of the first electrode layer is 60% or more. A permeation element in which, when an electric field is applied between the first electrode layer and the second electrode layer, the solvent in the solution leaches out through the first electrode layer.

2. The penetrating element according to claim 1, wherein the first electrode layer is a cathode layer.

3. The permeable element according to claim 1, wherein the conductive porous material includes a carbon material.

4. The permeable element according to claim 3, wherein the carbon material includes a nanocarbon material.

5. The permeable element according to claim 4, wherein the nanocarbon material includes carbon nanotubes.

6. The permeable element according to claim 5, wherein the carbon nanotube includes a single-walled carbon nanotube.

7. The penetrating element according to claim 1, wherein the first electrode layer is a sheet-like structure.

8. The permeable element according to claim 7, wherein the sheet-like structure does not contain a binder.

9. A conductive porous material layer formed from a conductive porous material, A first electrode formed on one surface of the conductive porous material layer, A second electrode formed on the other surface of the conductive porous material layer, The solution comprises the conductive porous material layer and the solution disposed on the other side of the conductive porous material layer, A permeation element in which, when an electric field is applied between the first electrode and the second electrode while the solution is in contact with the second electrode, the solvent in the solution leaches out toward the first electrode through the conductive porous material layer.

10. The penetrating element according to claim 9, wherein the first electrode is a cathode.

11. The permeable element according to claim 9, wherein the conductive porous material includes a nanocarbon material.

12. The permeable element according to claim 9, wherein the conductive porous material layer is a sheet-like structure.

13. A permeation apparatus comprising a permeation element according to any one of claims 1 to 12 and a DC power supply.

14. A penetration method using a penetration element according to any one of claims 1 to 12, A penetration method comprising applying an electric field to the first electrode layer and the second electrode layer, or to the first electrode and the second electrode.

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