Pervaporation membrane

Abstract

The present invention provides a novel pervaporation membrane suitable for separating a volatile organic compound from an aqueous solution containing the organic compound. This pervaporation membrane (10) is provided with a separation function layer (1) and a porous support body (5) that supports the separation function layer (1). The porous support (5) has a surface (A1) facing the separation function layer (1) and including a plurality of openings (H1), and the average diameter (L1) of the plurality of openings (H1) is 0.5 [mu] m or more. The pervaporation membrane (10) has a peel strength of 0.15 N / 20 mm or more as measured by the following test. Testing: cutting the pervaporation membrane 10 to obtain a test piece with the width of 20mm and the length of 150mm; the separation functional layer (1) is peeled off from the porous support (5) using a test piece at a peeling angle of 180 DEG and a tensile rate of 300 mm / min.

Description

Technical Field

[0001] The present invention relates to pervaporation membranes. Background Art

[0002] As a method for obtaining a valuable substance derived from non-petroleum, a method for utilizing fermentation based on microorganisms is known. For example, a method for producing volatile organic compounds (fermentation products) such as alcohol by fermenting carbon sources such as glucose using microorganisms has been developed. The fermentation of the carbon source is carried out, for example, in an aqueous solution. In this method, if the content of the fermentation product in the aqueous solution increases, the fermentation based on microorganisms is sometimes stopped. In order to continuously manufacture the fermentation product based on microorganisms, it is necessary to separate the fermentation product from the aqueous solution.

[0003] As an example of a method for separating a volatile organic compound from an aqueous solution containing the organic compound, a pervaporation method (pervaporation method) using a pervaporation membrane can be cited. The pervaporation method is suitable for separating volatile organic compounds from aqueous solutions containing various substances. Compared with the distillation method, the pervaporation method also tends to suppress energy consumption and carbon dioxide emissions. Patent Document 1 discloses an example of a pervaporation membrane used in the pervaporation method.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application No. 2005-525224 Summary of the invention

[0007] Problems to be solved by the invention

[0008] There is a need for new pervaporation membranes suitable for separating volatile organic compounds from aqueous solutions containing such organic compounds.

[0009] Means for solving problems

[0010] The present invention provides a pervaporation membrane, which has:

[0011] separating the functional layers; and

[0012] a porous support for supporting the separation functional layer,

[0013] The porous support has a surface A1 facing the separation functional layer and including a plurality of openings H1.

[0014] The average diameter L1 of the plurality of openings H1 is 0.5 μm or more.

[0015] The peel strength measured by the following test is 0.15 N / 20 mm or more.

[0016] Test: The pervaporation membrane was cut into a test piece of 20 mm in width x 150 mm in length. Using the test piece, the separation functional layer was peeled off from the porous support at a peeling angle of 180° and a tensile speed of 300 mm / min.

[0017] In addition, the present invention provides a pervaporation membrane comprising:

[0018] separating the functional layers; and

[0019] a porous support body, which is in direct contact with the separation functional layer and supports the separation functional layer;

[0020] The porous support is a fiber structure.

[0021] Effects of the Invention

[0022] According to the present invention, it is possible to provide a novel pervaporation membrane suitable for separating volatile organic compounds from an aqueous solution containing the organic compounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] [ Figure 1A ] is a cross-sectional view schematically showing a permeation vaporization membrane according to one embodiment of the present invention.

[0024] [ Figure 1B ] is a diagram for explaining a method for manufacturing a pervaporation membrane.

[0025] [ Figure 1C ] is a diagram for explaining a method for manufacturing a pervaporation membrane.

[0026] [ Figure 2 ] is a schematic cross-sectional view of a membrane separation device equipped with a pervaporation membrane.

[0027] [ Figure 3 ] is a stereoscopic view schematically showing a modified example of the membrane separation device.

[0028] [ Figure 4 ] is a schematic diagram showing an example of a membrane separation system. DETAILED DESCRIPTION

[0029] A pervaporation membrane according to a first aspect of the present invention comprises:

[0030] separating the functional layers; and

[0031] a porous support for supporting the separation functional layer,

[0032] The porous support has a surface A1 facing the separation functional layer and including a plurality of openings H1.

[0033] The average diameter L1 of the plurality of openings H1 is 0.5 μm or more.

[0034] The peel strength measured by the following test is 0.15 N / 20 mm or more.

[0035] Test: The pervaporation membrane was cut into a test piece of 20 mm in width x 150 mm in length. Using the test piece, the separation functional layer was peeled off from the porous support at a peeling angle of 180° and a tensile speed of 300 mm / min.

[0036] In the second aspect of the present invention, for example, in the pervaporation membrane according to the first aspect, the porous support has a surface A2 facing the surface A1 and including a plurality of openings H2, and an average diameter L2 of the plurality of openings H2 is 0.5 μm or more.

[0037] In a third aspect of the present invention, for example, in the pervaporation membrane according to the first or second aspect, the porous support is a fiber structure.

[0038] A fourth aspect of the present invention is a pervaporation membrane comprising:

[0039] separating the functional layers; and

[0040] a porous support body, which is in direct contact with the separation functional layer and supports the separation functional layer;

[0041] The porous support is a fiber structure.

[0042] In a fifth aspect of the present invention, for example, in the pervaporation membrane according to the third or fourth aspect, the fiber structure is a nonwoven fabric or a stretched porous membrane containing fibrils.

[0043] In the sixth aspect of the present invention, for example, in the permeation vaporization membrane involved in any one of the first to fifth aspects, the air permeability of the aforementioned porous support in the thickness direction is represented by the air permeability determined by the air permeability measurement B method (Gurley method) specified in JIS L1096:2010 and is less than 50 seconds / 100 mL.

[0044] In a seventh aspect of the present invention, for example, in the pervaporation membrane according to any one of the first to sixth aspects, the separation functional layer contains a silicone resin.

[0045] In the 8th aspect of the present invention, for example, in the permeation vaporization membrane involved in the 7th aspect, the aforementioned porous support body has a surface A1 opposite to the aforementioned separation functional layer and has been subjected to a treatment based on a molecular binder, and the aforementioned molecular binder contains a compound having a reactive group F1 capable of reacting with the aforementioned surface A1 and a reactive group F2 capable of reacting with the aforementioned silicone resin contained in the aforementioned separation functional layer.

[0046] In a ninth aspect of the present invention, for example, in the pervaporation membrane according to any one of the first to sixth aspects, the separation functional layer contains a (meth)acrylic resin.

[0047] In a tenth aspect of the present invention, for example, in the pervaporation membrane according to any one of the first to ninth aspects, the separation functional layer contains a filler.

[0048] In an eleventh aspect of the present invention, for example, in the pervaporation membrane according to the tenth aspect, the filler includes at least one selected from the group consisting of zeolite and silica.

[0049] In a twelfth aspect of the present invention, for example, the pervaporation membrane according to any one of the first to eleventh aspects is used to separate a volatile organic compound from an aqueous solution containing the organic compound.

[0050] In a thirteenth aspect of the present invention, for example, in the pervaporation membrane according to the twelfth aspect, the organic compound is a fermentation product produced by a microorganism.

[0051] Hereinafter, the present invention will be described in detail, but the following description is not intended to limit the present invention to specific embodiments.

[0052] <Embodiment of pervaporation membrane>

[0053] like Figure 1A As shown, the pervaporation membrane 10 of the present embodiment includes a separation functional layer 1 and a porous support 5 supporting the separation functional layer 1. The separation functional layer 1 has, for example, a surface 1a directly in contact with the porous support 5 and a surface exposed to the outside of the pervaporation membrane 10. The pervaporation membrane 10 is, for example, composed only of the separation functional layer 1 and the porous support 5. The pervaporation membrane 10 is typically a membrane (separation membrane) that preferentially allows volatile organic compounds C to pass through an aqueous solution S containing the organic compound C.

[0054] The porous support 5 has surfaces A1 and A2 facing each other. The surface A1 faces the separation functional layer 1, and more specifically, faces the separation functional layer 1 side. The surface A1 is, for example, directly in contact with the separation functional layer 1. The surface A1 includes a plurality of openings H1. The openings H1 are, for example, connected to the pores contained in the porous support 5. When the porous support 5 is a fiber structure, the openings H1 are typically gaps between fibers in the surface A1.

[0055] The average diameter L1 of the plurality of openings H1 is 0.5 μm or more, preferably 1 μm or more, 2 μm or more, 5 μm or more, 8 μm or more, 10 μm or more, 13 μm or more, and may be 15 μm or more. The upper limit of the average diameter L1 is not particularly limited, and may be, for example, 10 mm or less, 1 mm or less, 100 μm or less, or 50 μm or less.

[0056] The average diameter L1 can be determined by the following method. First, a scanning electron microscope (SEM) is used to observe the surface A1 of the porous support 5. The observation of the surface A1 is performed, for example, on the porous support 5 taken out from the pervaporation membrane 10. It should be noted that the observation of the surface A1 can also be performed on the porous support 5 before being used for the production of the pervaporation membrane 10.

[0057] The magnification and observation range of the SEM when observing the surface A1 can be appropriately adjusted according to the size of the opening H1. Examples of the magnification of the SEM are 50 times, 5000 times, 20000 times, etc. As an example, when the porous support 5 is a non-woven fabric and the opening H1 is large, the magnification of the SEM is adjusted to about 50 times, and in the obtained SEM image, the opening H1 is determined within a range larger than 2.0 mm × 2.5 mm in length. Assuming that the porous support 5 has a microporous layer and the opening H1 is small, the magnification of the SEM is adjusted to about 20000 times, and in the obtained SEM image, the opening H1 is determined within a range larger than 4.8 μm × 6.0 μm in length. In detail, the determination of the opening H1 is performed by using software (e.g., ImageJ) to convert the SEM image into a binary image of the opening H1 and other parts (non-openings) other than the opening H1. For each opening H1 determined, the area (opening area h) is calculated by image processing. For each opening H1, the diameter of a circle having the same area as the calculated area is regarded as the diameter d of the opening H1. Based on the obtained result, the average diameter L1 can be determined by the following formula. It should be noted that, as shown in the following formula, the average diameter L1 is a weighted average of the diameter d weighted by the opening area h.

[0058] Average diameter L1 (μm) = Σ {opening area h (μm 2)×diameter d(μm) / Σopening area h(μm 2 )

[0059] The opening ratio R1 of the surface A1 is not particularly limited, and may be, for example, 70% or less, 50% or less, or 30% or less. The opening ratio R1 may be 1 to 30%. The opening ratio R1 can be measured by the following method. First, the surface 5a of the porous support 5 is observed by SEM by the method described above for the average diameter L1, and the opening H1 is determined. The ratio of the total area occupied by the opening H1 in the SEM image can be regarded as the opening ratio R1.

[0060] Similar to the surface A1, the surface A2 of the porous support 5 includes, for example, a plurality of openings H2. The openings H2 are connected to, for example, pores included in the porous support 5. When the porous support 5 is a fiber structure, the openings H2 are typically gaps between fibers in the surface A2.

[0061] The average diameter L2 of the plurality of openings H2 is 0.5 μm or more, preferably 1 μm or more, 2 μm or more, 5 μm or more, 8 μm or more, 10 μm or more, 13 μm or more, and may be 15 μm or more. The upper limit of the average diameter L2 is not particularly limited, and may be, for example, 10 mm or less, 1 mm or less, 100 μm or less, or 50 μm or less. The average diameter L2 can be determined by the method described above for the average diameter L1.

[0062] The average diameter L2 may be the same as the average diameter L1 described above, or may be a value greater than the average diameter L1. As an example, the ratio L2 / L1 of the average diameter L2 (μm) to the average diameter L1 (μm) is, for example, 0.3 to 30. The ratio L2 / L1 is, for example, 30 or less, 25 or less, 20 or less, 15 or less, 10 or less, 5 or less, or 3 or less. The ratio L2 / L1 is, for example, 0.3 or more, 0.5 or more, or 0.8 or more.

[0063] The aperture ratio R2 of the surface A2 is not particularly limited, and may be, for example, less than 70%, less than 50%, or less than 30%. The aperture ratio R2 may be 1 to 30%. The aperture ratio R2 can be measured by the method described above for the aperture ratio R1. The aperture ratio R2 of the surface A2 may be the same as the aperture ratio R1, or may be a value higher than the aperture ratio R1. As an example, the absolute value |R2-R1| of the difference between the aperture ratio R2 (%) and the aperture ratio R1 (%) is, for example, less than 30%, less than 20%, less than 10%, or less than 5%.

[0064] The peel strength of the pervaporation membrane 10 according to the present embodiment measured by the following test is 0.15 N / 20 mm or more.

[0065] Test: The pervaporation membrane 10 was cut into a test piece of 20 mm in width and 150 mm in length. Using the test piece, the separation functional layer 1 was peeled off from the porous support 5 at a peeling angle of 180° and a tensile speed of 300 mm / min.

[0066] In detail, the above test is carried out by the following method. First, the permeation vaporization membrane 10 to be evaluated is cut into a width of 20 mm × length of 150 mm as a test piece. Then, the entire surface of the porous support 5 possessed by the test piece is overlapped with the acrylic resin test plate via a double-sided tape (for example, No. 5000NS manufactured by Nitto Denko Corporation), and a 2 kg roller is reciprocated once to crimp them. The acrylic resin test plate has a size of, for example, 150 mm in width × 150 mm in length. Then, in the direction from one end of the test piece toward the other end, the separation function layer 1 is peeled off only 90 mm from the porous support 5 by hand. Using a commercially available tensile testing machine, the peeled separation function layer 1 and one end of the test piece are grasped with a chuck, and the remaining separation function layer 1 is peeled off from the porous support 5 at a peeling angle of 180° and a tensile speed of 300 mm / min. The average value of the peeling force at this time is determined as the peeling strength. It should be noted that the initial distance between chucks in the tensile tester was 150 mm. The test was performed in an atmosphere of 25°C.

[0067] In the above test, when the separation functional layer 1 is soft and difficult to hold directly with a chuck, the following method using an evaluation sheet can also be implemented. First, the permeation vaporization membrane 10 to be evaluated is cut into a width of 20 mm × length of 150 mm as a test piece. The surface of the separation functional layer 1 possessed by the test piece is overlapped with the evaluation sheet as a whole, and a 2 kg roller is reciprocated once to press them. Next, the surface of the porous support body 5 possessed by the test piece is overlapped with the acrylic resin test plate as a whole via a double-sided tape (for example, No. 5000NS manufactured by Nitto Denko Corporation), and a 2 kg roller is reciprocated once to press them. Instead of holding the evaluation sheet with a chuck, the separation functional layer 1 is peeled off from the porous support body 5 by the same method as the above method. The average value of the peeling force at this time can be determined as the peeling strength. It should be noted that the evaluation sheet can be any sheet that is not peeled off from the separation functional layer 1 during the test, and is not particularly limited. As an example, when the separation functional layer 1 contains a (meth)acrylic resin, a film made of polyethylene terephthalate (PET) can be used as the evaluation sheet.

[0068] The peel strength is preferably 0.2N / 20mm or more, and can be 0.3N / 20mm or more, 0.4N / 20mm or more, 0.5N / 20mm or more, 0.6N / 20mm or more, 0.7N / 20mm or more, 0.8N / 20mm or more, 0.9N / 20mm or more, or 1.0N / 20mm or more. The upper limit of the peel strength is not particularly limited, and can be, for example, 20N / 20mm or 10N / 20mm.

[0069] It should be noted that in the above test, the following situation exists, that is, since the separation functional layer 1 is sufficiently fixed to the porous support 5, the separation functional layer 1 cannot be peeled off from the porous support 5 by hand, and if it is forcibly peeled off, the separation functional layer 1 will break. It is speculated that this phenomenon is due to the above-mentioned peel strength (N / 20mm) being greater than the fracture strength (N / 20mm) of the separation functional layer 1. Therefore, in this case, the fracture strength of the separation functional layer 1 can be determined separately, and the above-mentioned peel strength is regarded as a value above the fracture strength (that is, peel strength A1 (N / 20mm) ≥ fracture strength (N / 20mm)).

[0070] The breaking strength of the separation functional layer 1 can be determined by the following method. First, a layer having the same composition and thickness as the separation functional layer 1 of the pervaporation membrane 10 is prepared on a release liner, and the release liner is removed to prepare a self-supporting film of the separation functional layer 1. Next, a test piece of 20 mm in width and 60 mm in length is cut from the self-supporting film of the separation functional layer 1. The test piece is placed in a commercially available tensile testing machine, and a tensile test is performed under the following measurement conditions.

[0071] ·Measurement conditions

[0072] Temperature: 25℃

[0073] Tensile direction: length direction of the test piece

[0074] Initial distance between chucks: 20mm

[0075] Stretching speed: 300mm / min

[0076] In the tensile test, the strength B (N / mm 2 ). Based on strength B (N / mm 2 ), the thickness of the separation functional layer (mm) and the width of the test piece (20 mm), the breaking strength (N / 20 mm) can be calculated by the following formula.

[0077] Breaking strength (N / 20mm) = Strength B (N / mm 2 )×thickness(mm)×20×(1 / 20)

[0078] (Separation Functional Layer)

[0079] The separation functional layer 1 is, for example, a layer that allows the organic compound C to preferentially permeate the aqueous solution S, and is typically a dense layer (non-porous layer) in which no pores are observed when observed at a magnification of 5000 times using a scanning electron microscope (SEM).

[0080] In a preferred embodiment of the present invention, the separation functional layer 1 contains a silicone resin. The silicone resin is formed, for example, from a silicone resin composition. The silicone resin may be a resin formed from a condensation-type silicone resin composition, but is preferably a resin formed from an addition-type silicone resin composition. The silicone resin may be a resin formed from a UV-curable silicone resin composition. The addition-type silicone resin composition can be cured with almost no use of metal species (especially tin) that promotes hydrolysis of the silicone resin. Therefore, the separation functional layer 1 containing a silicone resin formed from an addition-type silicone resin composition contains almost no metal species that promotes hydrolysis of the silicone resin, and tends to have high durability against the above-mentioned aqueous solution S.

[0081] [Addition type silicone resin composition]

[0082] The addition type silicone resin composition is a type of silicone resin composition that is cured by an addition reaction. The addition type silicone resin composition, for example, comprises a polyorganosiloxane P1 having an alkenyl group and a polyorganosiloxane P2 having a hydrosilane (SiH) group. The addition type silicone resin composition preferably further comprises a curing catalyst (hydrosilylation catalyst). It should be noted that the addition type silicone resin composition may be a material in which a curing catalyst is added to a commercially available silicone resin composition. However, the addition type silicone resin composition may not contain a curing catalyst.

[0083] The addition type silicone resin composition can be formed into a silicone resin by, for example, heat treatment to cause the alkenyl group of polyorganosiloxane P1 to react with the hydrosilyl group of polyorganosiloxane P2 (hydrosilylation reaction). In the hydrosilylation reaction, polyorganosiloxane P2 functions as a crosslinking agent.

[0084] Examples of the alkenyl group in the polyorganosiloxane P1 include vinyl and hexenyl groups. The number of alkenyl groups in the polyorganosiloxane P1 is, for example, 2 or more. The alkenyl group is, for example, located at the terminal of the polyorganosiloxane P1.

[0085] The polyorganosiloxane P1 is, for example, a polyalkylalkylsiloxane such as polydimethylsiloxane, polydiethylsiloxane, polymethylethylsiloxane; a polyalkylarylsiloxane; a polyorganosiloxane such as poly(dimethylsiloxane-diethylsiloxane) into which an alkenyl group is introduced.

[0086] The weight average molecular weight of the polyorganosiloxane P1 is, for example, 1000 or more, 10,000 or more, 100,000 or more, 200,000 or more, 300,000 or more, or 400,000 or more. The larger the weight average molecular weight of the polyorganosiloxane P1, the more the separation characteristics of the pervaporation membrane 10 tend to be improved. The upper limit of the weight average molecular weight of the polyorganosiloxane P1 is not particularly limited, and is, for example, 1,000,000.

[0087] The number of hydrosilyl groups in the polyorganosiloxane P2 is, for example, not less than 2. The hydrosilyl group may be located at the terminal of the polyorganosiloxane P2 or may be included in the main chain of the polyorganosiloxane P2.

[0088] Examples of the polyorganosiloxane P2 include polymethylhydrogensiloxane, poly(dimethylsiloxane-methylhydrogensiloxane), and hydrosilyl-terminated polydimethylsiloxane.

[0089] The weight average molecular weight of the polyorganosiloxane P2 is, for example, 100 or more, and may be 10,000 or more. The larger the weight average molecular weight of the polyorganosiloxane P2, the more the separation characteristics of the pervaporation membrane 10 tend to improve. The upper limit of the weight average molecular weight of the polyorganosiloxane P2 is not particularly limited, and is, for example, 1,000,000.

[0090] The weight ratio P2 / P1 of polyorganosiloxane P2 to polyorganosiloxane P1 is, for example, 500 wt% (weight %) or less, and may be 100 wt% or less, 50 wt% or less, 20 wt% or less, 10 wt% or less, or 5 wt% or less. The lower limit of the weight ratio P2 / P1 is, for example, 0.01 wt% or more.

[0091] As a curing catalyst, for example, a platinum-based catalyst can be cited. In other words, the addition-type silicone resin composition may contain a curing catalyst containing platinum. Specific examples of the platinum-based catalyst are chloroplatinic acid, an olefin complex of platinum, an olefin complex of chloroplatinic acid, and the like. As described above, the addition-type silicone resin composition may not contain a curing catalyst.

[0092] The addition type silicone resin composition may contain a compound that generates a catalyst active species that catalyzes an addition reaction when irradiated with active energy rays such as ultraviolet rays (UV). The addition type silicone resin composition containing such a compound can cause an addition reaction by, for example, UV irradiation.

[0093] The addition type silicone resin composition may contain an organic solvent in addition to the above-mentioned components. Examples of the organic solvent include hydrocarbon solvents such as cyclohexane, n-hexane, and n-heptane; aromatic solvents such as toluene and xylene; ester solvents such as ethyl acetate and methyl acetate; ketone solvents such as acetone and methyl ethyl ketone; and alcohol solvents such as methanol, ethanol, and butanol. The organic solvent may be used alone or in combination of two or more. The addition type silicone resin composition may also be a solvent-free type that does not substantially contain an organic solvent or the like.

[0094] [Condensation type silicone resin composition]

[0095] The condensation type silicone resin composition is a type of silicone resin composition that is cured by a condensation reaction. The condensation type silicone resin composition, for example, comprises a polyorganosiloxane P3 having a silanol (SiOH) group, and a silane compound P4 having functional groups such as an alkoxy group, an alkenyloxy group, an acyloxy group, an amino group, a ketoxime group, and an amide group. The condensation type silicone resin composition may further comprise a curing catalyst or may not comprise a curing catalyst. It should be noted that the condensation type silicone resin composition may also be obtained by adding a curing catalyst to a commercially available silicone resin composition.

[0096] The condensation type silicone resin composition can be formed into a silicone resin by, for example, heat-treating the silanol groups of the polyorganosiloxane P3 and the functional groups of the silane compound P4 to cause a reaction (condensation reaction) to proceed. In the condensation reaction, the silane compound P4 functions as a crosslinking agent.

[0097] The number of silanol groups in the polyorganosiloxane P3 is, for example, 2 or more. The silanol groups are, for example, located at the ends of the polyorganosiloxane P3. In the polyorganosiloxane P3, an alkyl group such as a methyl group or an ethyl group, a phenyl group, etc. may be introduced as a substituent of a side chain.

[0098] The polyorganosiloxane P3 is, for example, a product obtained by introducing a silanol group into the polyorganosiloxane described above with respect to the polyorganosiloxane P1.

[0099] The weight average molecular weight of polyorganosiloxane P3 is, for example, 1000 or more, 10,000 or more, 100,000 or more, 200,000 or more, 300,000 or more, or 400,000 or more. The upper limit of the weight average molecular weight of polyorganosiloxane P3 is not particularly limited, and is, for example, 1,000,000.

[0100] As described above, the silane compound P4 has functional groups such as an alkoxy group, an alkenyloxy group, an acyloxy group, an amino group, a ketoxime group, and an amide group. As an alkoxy group, a methoxy group, an ethoxy group, etc. can be mentioned. As an alkenyloxy group, an isopropenyloxy group, etc. can be mentioned. As an acyloxy group, an acetoxy group, etc. can be mentioned. As an amino group, a dimethylamino group, a diethylamino group, an ethylmethylamino group, etc. can be mentioned. As a ketoxime group, an acetoxime group, a methylethylketoxime group, etc. can be mentioned. As an amide group, an acetamide group, an N-methylacetamide group, an N-ethylacetamide group, etc. can be mentioned. The number of functional groups in the silane compound P4 is, for example, more than 2. In detail, the silane compound P4 preferably contains an alkoxysilyl group as an alkoxy group.

[0101] The silane compound P4 may be a low molecular weight compound having a molecular weight of about 1000 or less, or may be a high molecular weight compound having a polysiloxane skeleton.

[0102] Examples of the curing catalyst include tin catalysts and organic tin catalysts such as dibutyltin dilaurate, dibutyltin diacetate, and dibutyltin dioctoate.

[0103] The condensation type silicone resin composition may contain an organic solvent in addition to the above components. Examples of the organic solvent include the organic solvents described above for the addition type silicone resin composition. The condensation type silicone resin composition may be a solvent-free type that does not contain a solvent such as an organic solvent.

[0104] [UV curable silicone resin composition]

[0105] The UV-curable silicone resin composition is a silicone resin composition of the type that is cured by ultraviolet (UV) irradiation. The UV-curable silicone resin composition undergoes a curing reaction, for example, by free radical polymerization, free radical addition, ionic polymerization, and the like. The UV-curable silicone resin composition that undergoes a curing reaction by free radical polymerization, for example, includes a polyorganosiloxane P5 having a double bond (specifically, a carbon-carbon double bond) derived from an alkenyl group, an acryloyl group, and the like. The UV-curable silicone resin composition that undergoes a curing reaction by free radical addition, for example, includes a polyorganosiloxane P5 having a double bond (specifically, a carbon-carbon double bond) derived from an alkenyl group, an acryloyl group, and the like, and a compound P6 having a functional group such as a thiol group that can undergo free radical addition. The UV-curable silicone resin composition that undergoes a curing reaction by ionic polymerization, for example, includes a polyorganosiloxane P7 having a functional group such as an epoxy group that can undergo ionic polymerization, and a compound that produces a catalyst active species that catalyzes ionic polymerization by UV irradiation.

[0106] According to the UV curable silicone resin composition that undergoes a curing reaction by radical polymerization, for example, double bonds contained in alkenyl groups, acryloyl groups, etc. of the polyorganosiloxane P5 undergo a radical polymerization reaction by UV irradiation, thereby forming a silicone resin.

[0107] Examples of the alkenyl group of the polyorganosiloxane P5 include vinyl and hexenyl groups. The number of alkenyl groups in the polyorganosiloxane P5 is, for example, 2 or more. The alkenyl group is, for example, located at the end of the polyorganosiloxane P5. In the polyorganosiloxane P5, as a substituent of the side chain, an alkyl group such as a methyl group or an ethyl group, a phenyl group, etc. may be introduced.

[0108] The polyorganosiloxane P5 is obtained by introducing a substituent having a double bond, such as an alkenyl group or an acryloyl group, into the polyorganosiloxane described above for the polyorganosiloxane P1, for example.

[0109] The weight average molecular weight of polyorganosiloxane P5 is, for example, 1000 or more, 10,000 or more, 100,000 or more, 200,000 or more, 300,000 or more, or 400,000 or more. The upper limit of the weight average molecular weight of polyorganosiloxane P5 is not particularly limited, and is, for example, 1,000,000.

[0110] According to the UV curable silicone resin composition that undergoes a curing reaction by free radical addition, for example, the functional group capable of free radical addition contained in compound P6 is free radically added to the double bond contained in the alkenyl group, acryloyl group, etc. of polyorganosiloxane P5 by UV irradiation, thereby allowing a free radical addition reaction to proceed and form a silicone resin.

[0111] In compound P6, the functional group capable of radical addition is, for example, a thiol group, an alkylthiol group, etc. Examples of the alkylthiol group include mercaptomethyl and mercaptoethyl groups. The number of the functional groups capable of radical addition in compound P6 is, for example, 2 or more.

[0112] Compound P6 may be a polyorganosiloxane containing a functional group capable of free radical addition. The functional group is, for example, located at the end of the polyorganosiloxane. In the polyorganosiloxane, an alkyl group such as a methyl group or an ethyl group, a phenyl group, etc. may be introduced as a substituent of a side chain.

[0113] Compound P6 is, for example, a compound obtained by introducing a functional group capable of radical addition, such as a thiol group, into the polyorganosiloxane described above with respect to polyorganosiloxane P1.

[0114] The weight average molecular weight of compound P6 is, for example, 1000 or more, 10,000 or more, 100,000 or more, 200,000 or more, 300,000 or more, or 400,000 or more. The upper limit of the weight average molecular weight of compound P6 is not particularly limited, and is, for example, 1,000,000.

[0115] According to the UV curable silicone resin composition that undergoes curing reaction by ion polymerization, for example, by UV irradiation, a catalyst active species that catalyzes ion polymerization is generated, and ion polymerizable functional groups contained in the polyorganosiloxane P7 undergo ion polymerization reaction with each other, thereby forming a silicone resin.

[0116] In the polyorganosiloxane P7, the functional group capable of ion polymerization is, for example, an epoxy group. Examples of the substituent containing the epoxy group include the epoxy group itself, a glycidyl group, a glycidyloxypropyl group, and the like. The number of the functional groups capable of ion polymerization in the polyorganosiloxane P7 is, for example, 2 or more. The functional group capable of ion polymerization is, for example, located at the end of the polyorganosiloxane P7. In the polyorganosiloxane P7, as a substituent of the side chain, an alkyl group such as a methyl group or an ethyl group, a phenyl group, and the like can be introduced.

[0117] The polyorganosiloxane P7 is obtained by, for example, introducing an ion-polymerizable functional group such as an epoxy group into the polyorganosiloxane described above for the polyorganosiloxane P1.

[0118] The weight average molecular weight of polyorganosiloxane P7 is, for example, 1000 or more, 10,000 or more, 100,000 or more, 200,000 or more, 300,000 or more, or 400,000 or more. The upper limit of the weight average molecular weight of polyorganosiloxane P7 is not particularly limited, and is, for example, 1,000,000.

[0119] In addition to the above-mentioned components, the UV-curable silicone resin composition may also contain an organic solvent. Examples of the organic solvent include hydrocarbon solvents such as cyclohexane, n-hexane, and n-heptane; aromatic solvents such as toluene and xylene; ester solvents such as ethyl acetate and methyl acetate; ketone solvents such as acetone and methyl ethyl ketone; alcohol solvents such as methanol, ethanol, and butanol, etc. The organic solvent may be used alone or in combination of two or more. The UV-curable silicone resin composition may also be a solvent-free type that does not substantially contain an organic solvent or other solvents.

[0120] The separation functional layer 1 may contain silicone resin as a main component, or may be substantially composed of silicone resin alone. The “main component” refers to the component that is contained in the largest amount by weight in the separation functional layer 1 .

[0121] In another preferred embodiment of the present invention, the separation functional layer 1 comprises a (meth) acrylic resin. The (meth) acrylic resin is formed, for example, from a monomer group comprising a (meth) acrylic monomer and / or a (meth) acrylic resin composition comprising a (meth) acrylic polymer. The (meth) acrylic resin composition may be a UV curable type or a thermal curable type.

[0122] As a (meth)acrylic-based monomer contained in a monomer group, the alkyl (meth)acrylate is mentioned, for example. In this specification, "(meth)acrylate" means an acrylate and / or a methacrylate.

[0123] The alkyl group contained in the (meth)acrylic acid alkyl ester is not particularly limited, and is, for example, a linear, branched, or cyclic alkyl group having 2 to 14 carbon atoms.

[0124] Examples of the (meth)acrylic acid alkyl ester include alkyl acrylates having an alkyl group with 2 to 14 carbon atoms, and preferably alkyl acrylates having an alkyl group with 4 to 9 carbon atoms. Examples of the alkyl acrylate include n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, isoamyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, nonyl acrylate, and isononyl acrylate.

[0125] The (meth)acrylic acid alkyl ester may be, for example, an alkyl methacrylate having an alkyl group with 2 to 14 carbon atoms, and preferably an alkyl methacrylate having an alkyl group with 2 to 10 carbon atoms. Examples of the alkyl methacrylate include ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, bornyl methacrylate, and isobornyl methacrylate.

[0126] The (meth)acrylic acid alkyl ester may be used alone or in combination of two or more thereof. The content of the (meth)acrylic acid alkyl ester in the monomer group is not particularly limited, and is, for example, 70 to 100 wt %, preferably 85 to 99 wt %, and more preferably 87 to 99 wt %.

[0127] The monomer group may further include a comonomer that can copolymerize with the alkyl (meth)acrylate. Examples of the comonomer include: carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; alkyl (meth)acrylates having an alkyl group with 1 or more carbon atoms; (meth)acrylate aryl esters such as phenyl (meth)acrylate; vinyl esters such as vinyl acetate and vinyl propionate; styrene-based monomers such as styrene; epoxy group-containing monomers such as glycidyl (meth)acrylate and methylglycidyl (meth)acrylate; hydroxyl group-containing (meth)acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; (meth)acrylamide, N,N-dimethyl (meth)acrylate ) acrylamide, N,N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide, (meth) acryloyl morpholine, aminoethyl (meth) acrylate, N,N-dimethylaminoethyl (meth) acrylate, tert-butylaminoethyl (meth) acrylate and other nitrogen atom-containing monomers; methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate and other alkoxy-containing monomers; acrylonitrile, methacrylonitrile and other cyano-containing monomers; 2-methacryloyloxyethyl isocyanate and other functional monomers; ethylene, propylene, isoprene, butanediol Olefin monomers such as olefins, isobutylene, etc.; vinyl ether monomers such as vinyl ether; halogen-containing monomers such as vinyl chloride; vinyl heterocyclic compounds such as N-vinylpyrrolidone, N-(1-methylvinyl)pyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, and N-vinylmorpholine; N-vinylcarboxamide; maleimide monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, and N-phenylmaleimide; N-methylitaconimide, N-ethylitaconimide, N -Itaconimide monomers such as butyl itaconimide, N-octyl itaconimide, N-2-ethylhexyl itaconimide, N-cyclohexyl itaconimide, and N-lauryl itaconimide; succinimide monomers such as N-(meth)acryloyloxymethylene succinimide, N-(meth)acryloyl-6-oxyhexamethylene succinimide, and N-(meth)acryloyl-8-oxyoctamethylene succinimide; sulfonic acid group-containing monomers such as styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropane sulfonic acid, (meth)acrylamidopropane sulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalene sulfonic acid; phosphoric acid group-containing monomers;Diol-based acrylate monomers such as polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, and methoxypolypropylene glycol (meth)acrylate; acrylate monomers containing heterocyclic rings or halogen atoms such as tetrahydrofurfuryl (meth)acrylate and fluoro(meth)acrylate; and compounds having reactive unsaturated double bonds such as allyl (meth)acrylate and vinyl (meth)acrylate. ;

[0128] The (meth)acrylic polymer may also be a polymer of the above-mentioned monomer group. The (meth)acrylic polymer preferably has a structural unit derived from an alkyl (meth)acrylate as a main component. As the alkyl (meth)acrylate, the above-mentioned substances can be cited. The content of the structural unit derived from the alkyl (meth)acrylate in the (meth)acrylic polymer is not particularly limited, and is, for example, 70 to 100 wt%, preferably 85 to 99 wt%, and more preferably 87 to 99 wt%.

[0129] The (meth)acrylic polymer may further include a structural unit derived from a comonomer copolymerizable with the (meth)acrylic acid alkyl ester. Examples of the comonomer include the above-mentioned monomers.

[0130] The (meth)acrylic resin composition may contain additives and organic solvents in addition to the monomer group and the (meth)acrylic polymer. Examples of additives include polymerization initiators, crosslinking agents, fillers described below, and the like. Examples of organic solvents include the organic solvents described above for the silicone resin composition. It should be noted that the (meth)acrylic resin composition may also be a solvent-free type that does not substantially contain an organic solvent or the like.

[0131] When the (meth)acrylic resin composition is a UV curable resin composition, the resin composition preferably contains a photopolymerization initiator as an additive.

[0132] Examples of photopolymerization initiators include benzoin ethers such as benzoin methyl ether, benzoin isopropyl ether, and benzyl dimethyl ketal; substituted benzoin ethers such as anisolemethyl ether; substituted acetophenones such as 2,2-diethoxyacetophenone and 2,2-dimethoxy-2-phenylacetophenone; α-hydroxyalkyl phenones such as 1-hydroxycyclohexyl phenyl ketone; substituted α-keto alcohols such as 2-methyl-2-hydroxypropiophenone; aromatic sulfonyl chlorides such as 2-naphthalenesulfonyl chloride; photoactive oximes such as 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime; benzophenone, benzoylbenzoic acid, benzoylbenzoic acid methyl ester, 4-phenylbenzophenone, hydroxybenzophenone, and acryloyl benzophenone. , 4-benzoyl-4'-methyldiphenyl sulfide, 3,3',4,4'-tetrakis(tert-butylperoxycarbonyl)benzophenone and other benzophenone compounds; thioxanthone compounds such as 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, 2,4-diethylthioxanthone, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-tolyl)- 4,6-bis(trichloromethyl)-s-triazine, 2-piperonyl-4,6-bis(trichloromethyl)-s-triazine, 2,4-bis(trichloromethyl)-6-phenylvinyl-s-triazine, 2-(naphthalene-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxy-naphthalene-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl-(piperonyl)-6-triazine, 2,4-trichloromethyl-(4'-methoxyphenylvinyl)-6-triazine and other triazine compounds; 1,2 -octanedione, 1-〔4-(phenylthio), 2-(O-benzoyloxime)〕, O-(acetyl)-N-(1-phenyl-2-oxo-2-(4'-methoxy-naphthyl)ethylidene)hydroxylamine and other oxime ester compounds; bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and other phosphine compounds; 9,10-phenanthrenequinone, camphorquinone, ethylanthraquinone and other quinone compounds; borate compounds; carbazole compounds; imidazole compounds; and titanocene compounds. The (meth)acrylic resin composition may contain one or more photopolymerization initiators.

[0133] The amount of the photopolymerization initiator in the (meth)acrylic resin composition is, for example, 0.02 to 10 parts by weight, or 0.05 to 5 parts by weight, based on 100 parts by weight of the monomer group.

[0134] When the (meth)acrylic resin composition is a UV curable resin, the resin composition preferably contains a crosslinking agent as an additive. Examples of the crosslinking agent are polyfunctional monomers having two or more polymerizable functional groups in one molecule.

[0135] Examples of the polyfunctional monomer include: (mono- or poly-)alkylene glycol di(meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetraethylene glycol di(meth)acrylate, and propylene glycol di(meth)acrylate; esters of (meth)acrylic acid and polyols such as neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; and polyfunctional vinyl compounds such as divinylbenzene.

[0136] The amount of the crosslinking agent in the (meth)acrylic resin composition is, for example, 5 parts by weight or less, 3 parts by weight or less, 2 parts by weight or less, 1 part by weight or less, or 0.5 parts by weight or less, based on 100 parts by weight of the monomer group. The lower limit of the amount is, for example, 0.01 parts by weight or more, or 0.05 parts by weight or more.

[0137] The separation functional layer 1 may contain a (meth)acrylic resin as a main component, or may be composed essentially of only a (meth)acrylic resin.

[0138] The separation function layer 1 may include a matrix containing a resin (silicone resin or (meth) acrylic resin) and a filler dispersed in the matrix. In this embodiment, in the separation function layer 1, all or part of the filler is embedded in the matrix. In the matrix, all the fillers may be separated from each other or partially aggregated.

[0139] The filler includes, for example, inorganic materials such as zeolite, silica, and bentonite. The filler includes, for example, at least one selected from the group consisting of zeolite and silica, preferably silica. Compared with fillers containing zeolite, fillers containing silica tend to have excellent hydrolysis resistance. Furthermore, by using fillers containing silica, the free volume of the resin (especially silicone resin) contained in the matrix tends to increase. If the free volume of the resin increases, the separation characteristics of the permeation vaporization membrane 10, especially the separation coefficient α of BuOH relative to water, tend to improve. By using fillers, the viscosity of the resin composition (especially the (meth) acrylic resin composition) can be appropriately adjusted, thereby, it also tends to be easy to prepare a resin composition suitable for coating.

[0140] Silica generally refers to silicon dioxide. The filler may be a silica filler containing silicon dioxide as a main component. The silica filler, for example, does not have a crystalline structure. The silica filler, for example, can be made by reacting metallic silicon with oxygen. The silica filler can be made by a sol-gel method, a sedimentation method, an aqueous solution wet method, etc. The filler may be substantially composed only of silicon dioxide.

[0141] However, the filler may also contain zeolite. As the zeolite contained in the filler, for example, high-silicon zeolite having a high ratio of silica to alumina and silica zeolite not containing alumina can be cited. As the filler containing high-silicon zeolite, HSZ (registered trademark) manufactured by Tosoh Corporation, HiSiv (registered trademark) manufactured by Union Showa Co., Ltd., USKY manufactured by Union Showa Co., Ltd., and Zeoal (registered trademark) manufactured by Nakamura Superhard Co., Ltd. can be used.

[0142] Fillers, especially silica fillers, for example, do not have micropores with a diameter of 2 nm or less. On the other hand, fillers may have mesopores with a diameter of 2 nm to 50 nm, and macropores with a diameter of 50 nm or more.

[0143] The filler, especially the silica filler, preferably has a surface modified by a modifying group containing a hydrocarbon group. In other words, the filler is preferably surface-modified by the modifying group. The surface-modified filler has high dispersibility in the resin and is suitable for suppressing the generation of cracks in the case of preparing the separation functional layer 1, etc.

[0144] The number of carbon atoms of the hydrocarbon group contained in the modifying group is not particularly limited, and is, for example, 1 to 25. The number of carbon atoms of the hydrocarbon group may be 5 or less. The hydrocarbon group may be linear, branched, or cyclic. Examples of the hydrocarbon group include alkyl groups such as methyl and ethyl groups.

[0145] The modifying group may further include a silicon atom, and a hydrocarbon group may be bonded to the silicon atom. The modifying group may include at least one selected from the group consisting of an organosilyl group and a polyorganosiloxane group. Examples of the organosilyl group include triorganosilyl groups such as trimethylsilyl and diorganosilyl groups such as dimethylsilyl. Examples of the polyorganosiloxane group include dimethylpolysiloxane groups, and the like.

[0146] The surface modification using the modifying group can be performed, for example, by reacting a hydroxyl group present on the surface of the filler with a known silane coupling agent.

[0147] Specific examples of surface-modified silica fillers include "AEROSIL (registered trademark) RX series" (RX50, RX200, RX300, etc.), "AEROSIL (registered trademark) RY series" (RY50, RY200, RY200S, etc.), "AEROSIL (registered trademark) NY series" (NY50, NY50L, etc.), "AEROSIL (registered trademark) NAX series" (NAX50, etc.), and "AEROSIL (registered trademark) R series" (R972, R974, R976, etc.) manufactured by Japan Aerosil Co., Ltd.

[0148] From the perspective of dispersibility in the resin, the filler is preferably sufficiently surface-modified by the modifying group. In other words, the number of hydroxyl groups present on the surface of the filler is preferably small. Whether the filler is sufficiently surface-modified by the modifying group can be judged, for example, based on the pH of the dispersion of the filler and the Hansen solubility parameter (HSP value) of the filler. It should be noted that the Hansen solubility parameter is obtained by dividing the solubility parameter introduced by Hildebrand into three components: the dispersion term δD, the polar term δP, and the hydrogen bond term δH. The details of the Hansen solubility parameters are disclosed in "Hansen Solubility Parameters; A Users Handbook (CRC Press, 2007)" and the like.

[0149] In this embodiment, the pH of the filler dispersion measured by the following test is, for example, 4.0 to 9.0, or 6.0 to 8.0. The pH of the dispersion is preferably neutral (near pH 7.0). When the pH of the dispersion is neutral, it can be said that the filler is fully surface-modified by the modifying group, and the number of hydroxyl groups present on the surface is small.

[0150] Test: Water, methanol and filler were mixed to prepare a dispersion, and the pH of the dispersion was measured. Here, the content of the filler in the dispersion was 4 wt%, the weight ratio of water to methanol was 1:1, and the temperature of the dispersion was 25°C.

[0151] The shape of the filler is, for example, particulate. In this specification, "particulate" includes spherical, ellipsoidal, scaly and fibrous. The filler can also be in powder form. The average particle size of the filler is not particularly limited, for example, it is less than 50 μm, it can be less than 20 μm, less than 10 μm, less than 1 μm, less than 500 nm, less than 100 nm, less than 50 nm, less than 30 nm, and can also be less than 20 nm. The separation functional layer 1 containing a filler with a small average particle size is easy to disperse the stress applied to the separation functional layer 1, and tends to have high adhesion with the porous support 5. This tendency is particularly significant in the separation functional layer 1 containing a silicone resin. It should be noted that in the separation functional layer 1 containing a (meth) acrylic resin, the addition of fillers sometimes reduces the adhesion between the separation functional layer 1 and the porous support 5. In this case, for example, if a filler having an average particle size of 20 nm or less is used and the amount thereof added is set small, there is a tendency that the adhesion between the separation functional layer 1 and the porous support 5 can be sufficiently ensured, and the viscosity of the (meth)acrylic resin composition used to prepare the separation functional layer 1 can be appropriately adjusted. The lower limit of the average particle size of the filler is not particularly limited, and is, for example, 1 nm or 5 nm.

[0152] The average particle size of the filler can be determined, for example, by the following method. First, a cross section of the separation functional layer 1 is observed using a transmission electron microscope. In the obtained electron microscope image, the area of ​​the specific filler is calculated by image processing. The diameter of a circle having the same area as the calculated area is regarded as the particle size (diameter of the particle) of the specific filler. The particle sizes of any number (at least 50) of fillers are calculated separately, and the average value of the calculated values ​​is regarded as the average particle size of the filler.

[0153] The content of the filler in the separation functional layer 1 is, for example, 1 wt% or more, 5 wt% or more, 10 wt% or more, 20 wt% or more, 30 wt% or more, or 40 wt% or more. The upper limit of the content of the filler in the separation functional layer 1 is not particularly limited, and is, for example, 70 wt% or less, or less than 50 wt%. When the content of the filler is less than 50 wt%, there is a tendency to fully suppress the occurrence of defects such as cracks when the separation functional layer 1 is made. The content of the matrix in the separation functional layer 1 is not particularly limited, and is, for example, 30 wt% to 99 wt%, or 30 wt% to 90 wt%.

[0154] The surface area D1 of the filler per unit weight of the substrate is not particularly limited, and is, for example, 5 m 2 / g or more, can be 10m 2 / g or more, 20m 2 / g or more, 30m 2 / g or more, 40m 2 / g or more, and can also be 50m2 The upper limit of the surface area D1 is not particularly limited, but is, for example, 100 m 2 The surface area D1 can be based on the BET specific surface area D2 (m 2 / g), the weight W1 (g) of the substrate contained in the separation functional layer 1, and the weight W2 (g) of the filler contained in the separation functional layer 1 are calculated according to the following formulas.

[0155] D1(m 2 / g)=D2(m 2 / g)×W2(g) / W1(g)

[0156] The thickness of the separation functional layer 1 is, for example, 200 μm or less, 100 μm or less, or 80 μm or less. The thickness of the separation functional layer 1 may be 1.0 μm or more, 10 μm or more, or 30 μm or more.

[0157] (Porous Support)

[0158] In the present embodiment, the porous support 5 has, for example, only a main body and no microporous layer. The porous support 5 is preferably a fiber structure. As the fiber structure, woven fabrics, non-woven fabrics, stretched porous films containing fibrils, etc. can be cited. The fiber structure is typically a non-woven fabric or a stretched porous film.

[0159] When the fiber structure is a woven fabric or a nonwoven fabric, the fibers contained in the fiber structure include, for example, natural fibers such as wood pulp, cotton, and hemp (e.g., Manila hemp); and chemical fibers (synthetic fibers) such as polyester fibers, rayon, vinylon, acetate fibers, polyvinyl alcohol (PVA) fibers, polyamide fibers, polyolefin fibers, and polyurethane fibers. The porous support 5 is, for example, a nonwoven fabric made of polyester fibers.

[0160] When the fiber structure is a stretched porous membrane, the fiber structure preferably includes a fluororesin. As the fluororesin, polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), perfluoroalkoxy fluororesin (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP) etc. can be cited, preferably PTFE.

[0161] For example, a PTFE stretched porous membrane is formed by stretching a paste extrudate or a cast film containing PTFE particles. The PTFE stretched porous membrane is composed of fine fibrils of PTFE, and may have nodes where PTFE is aggregated compared to the fibrils.

[0162] In this embodiment, the separation functional layer 1 is directly connected to the fiber structure (specifically, a nonwoven fabric or a stretched porous membrane). From another aspect, the present invention provides a pervaporation membrane 10, which comprises:

[0163] Separation functional layer 1; and

[0164] The porous support 5 is directly in contact with the separation functional layer 1 and supports the separation functional layer 1.

[0165] The porous support 5 is a fiber structure.

[0166] It should be noted that, when the separation functional layer 1 contains a (meth)acrylic resin and is directly in contact with the porous support 5 as a fiber structure, during the operation of the membrane separation device equipped with the pervaporation membrane 10, a part of the separation functional layer 1 enters the opening H1 of the porous support 5, and the flux of the permeating fluid passing through the pervaporation membrane 10 may decrease. However, according to the research of the inventors of the present application, even when the separation functional layer 1 contains a (meth)acrylic resin, if a stretched porous membrane is used as the porous support 5, the separation functional layer 1 is not easy to enter the opening H1, and there is a tendency that the decrease in the flux of the permeating fluid is sufficiently suppressed.

[0167] The porous support 5 (main body) has an average pore size of, for example, 1 μm to 50 μm. The thickness of the porous support 5 is not particularly limited, and is, for example, 10 μm or more, 50 μm or more, or 100 μm or more. The thickness of the porous support 5 is, for example, 300 μm or less, or 200 μm or less.

[0168] In the present embodiment, the porous support 5 has a large average diameter L1 of the opening H1 in the surface A1, so there is a tendency for the air permeability to be high when used alone. As an example, the air permeability in the thickness direction of the porous support 5 is represented by the air permeability (Gurley air permeability) obtained by the air permeability measurement B method (Gurley method) specified in JIS L1096:2010, for example, 50 seconds / 100mL or less, 30 seconds / 100mL or less, 10 seconds / 100mL or less, and 5 seconds / 100mL or less. The lower limit of the Gurley air permeability of the porous support 5 is not particularly limited, for example, 0.1 seconds / 100mL.

[0169] The surface A1 of the porous support 5 can be treated with a molecular bonding agent. The molecular bonding agent contains a molecular bonding compound (hereinafter referred to as "compound C1") and contains a solvent such as an organic solvent and water as needed. Compound C1 has a reactive group F1 that can react with the surface A1 of the porous support 5, and a reactive group F2 that can react with the resin (especially silicone resin) contained in the separation functional layer 1. The reactive group F2 can react not only with the silicone resin, but also with the surface A1 of the porous support 5.

[0170] The reactive group F1 is, for example, at least one selected from the group consisting of an amino group, an azido group, a mercapto group, an isocyanate group, a urea group, and an epoxy group, and is typically an azido group. The reactive group F2 is, for example, at least one selected from the group consisting of a silanol group and a group G that generates a silanol group by a hydrolysis reaction. A specific example of the group G is an alkoxysilyl group.

[0171] Compound C1 is represented by, for example, the following formula (1).

[0172] R A -ZR B (1)

[0173] In formula (1), R A represents a reactive group F1 or a monovalent substituent having one or more reactive groups F1, R B represents a reactive group F2, and Z represents a divalent organic group.

[0174] In formula (1), Z includes an alkylene group having 1 to 20 carbon atoms which may have a substituent, an alkenylene group having 2 to 20 carbon atoms which may have a substituent, an alkynylene group having 2 to 20 carbon atoms which may have a substituent, and an arylene group having 6 to 20 carbon atoms which may have a substituent.

[0175] Examples of the alkylene group having 1 to 20 carbon atoms include methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, and hexamethylene, and are preferably methylene, ethylene, and propylene, and more preferably propylene. Examples of the alkenylene group having 2 to 20 carbon atoms include vinylene, propenylene, butenylene, and pentenylene. Examples of the alkynylene group having 2 to 20 carbon atoms include ethynylene and propynylene. Examples of the arylene group having 6 to 20 carbon atoms include o-phenylene, m-phenylene, p-phenylene, 2,6-naphthylene, and 1,5-naphthylene.

[0176] Examples of the substituent which the alkylene group, alkenylene group and alkynylene group may have include halogen atoms such as fluorine atom and chlorine atom; alkoxy groups such as methoxy group and ethoxy group; alkylthio groups such as methylthio group and ethylthio group; and alkoxycarbonyl groups such as methoxycarbonyl group and ethoxycarbonyl group.

[0177] Examples of the substituent which the arylene group may have include a cyano group; a nitro group; a halogen atom such as a fluorine atom, a chlorine atom, or a bromine atom; an alkyl group such as a methyl group or an ethyl group; an alkoxy group such as a methoxy group or an ethoxy group; and an alkylthio group such as a methylthio group or an ethylthio group.

[0178] The above-mentioned substituents may be bonded to any position in the groups such as the alkylene group, the alkenylene group, the alkynylene group and the arylene group, and a plurality of substituents may be bonded to the same element or different elements.

[0179] As R A For example, groups represented by the following formulae (2) to (4) are mentioned.

[0180] [Chemical formula 1]

[0181]

[0182] In formulae (2) to (4), * represents a bond with Z in formula (1). 1 represents a divalent hydrocarbon group having 1 to 10 carbon atoms. 2 and R 3 Each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. 4 and R 5 Each independently represents a reactive group F1 or a group represented by the above formula (2). 4 and R 5 In the case of a group represented by formula (2), in formula (2), * represents a bond to a carbon atom constituting a triazine ring in formula (4). 6 Represents a single bond, or -N(R 7 )- is a divalent group. 7 It represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

[0183] In formula (2), as R 1 , preferably a divalent hydrocarbon group having 2 to 6 carbon atoms. 1 For example, there can be mentioned an alkylene group or an arylene group having 1 to 10 carbon atoms, and specifically, there can be mentioned an alkylene group such as ethylene and trimethylene; and an arylene group such as o-phenylene, m-phenylene and p-phenylene.

[0184] In formula (2), R 2 and R 3 Each of R is independently preferably a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. 2 and R 3, for example, alkyl, alkynyl or aryl groups having 1 to 20 carbon atoms can be mentioned, and specifically, alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl and n-decyl can be mentioned; alkenyl groups such as vinyl, 1-propenyl, 2-propenyl, isopropenyl, 3-butenyl, 4-pentenyl and 5-hexenyl can be mentioned; alkynyl groups such as ethynyl, propargyl and butynyl can be mentioned; and aryl groups such as phenyl, 1-naphthyl and 2-naphthyl can be mentioned.

[0185] In formula (4), R 4 and R 5 The reactive groups F1 are preferably identical to one another.

[0186] In formula (4), R 6 Represents a single bond, or -N(R 7 )- is a divalent group. 7 The hydrocarbon group may be the same as the above R 2 and R 3 The hydrocarbon group is the same as the group described above. 6 Preferably it represents -NH-.

[0187] R A Preferred is the group represented by formula (4) among the groups represented by formulas (2) to (4), and more preferred is the group represented by formula (4) in which R 4 or R 5 is an azido group or a group represented by the above formula (2).

[0188] As R A , for example, a group represented by the following formula (5) can be mentioned.

[0189] [Chemical formula 2]

[0190]

[0191] In formula (5), * represents a bond with Z in formula (1). 1 ~R 3 and R 6 are the same as those described above for formulae (2) and (4). 1 ~R 3 They can be the same or different from each other.

[0192] In formula (1), R B It may be a group represented by the following formula (6).

[0193] -Si(X) a (Y) 3-a (6)

[0194] In formula (6), X represents a hydroxyl group or an alkoxy group having 1 to 10 carbon atoms, and Y represents a hydrocarbon group having 1 to 20 carbon atoms. a represents an integer of 1 to 3.

[0195] In the formula (6), X includes, for example, methoxy, ethoxy, n-propoxy, isopropoxy, etc., preferably ethoxy. Y includes R in the formula (2): 2 and R 3 The hydrocarbon group is not the group described above.

[0196] R B Preferably, X represents a hydroxyl group or an alkoxy group having 1 to 10 carbon atoms, and a is 3. More preferably, X represents a hydroxyl group or an ethoxy group, and a is 3.

[0197] As R A Examples of the amino compound C1 include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldimethoxymethylsilane, 3-aminopropyldiethoxymethylsilane, [3-(N,N-dimethylamino)propyl]trimethoxysilane, [3-(phenylamino)propyl]trimethoxysilane, trimethyl[3-(triethoxysilyl)propyl]ammonium chloride, and trimethyl[3-(trimethoxysilyl)propyl]ammonium chloride.

[0198] As R A Examples of the compound C1 which is an azido group include (11-azidoundecyl)trimethoxysilane and (11-azidoundecyl)triethoxysilane.

[0199] As R A Examples of the compound C1 which is a mercapto group include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-mercaptopropyldimethoxymethylsilane.

[0200] As R A Examples of the isocyanate group of compound C1 include 3-(trimethoxysilyl)propyl isocyanate and 3-(triethoxysilyl)propyl isocyanate.

[0201] As R A Examples of the ureido compound C1 include 3-ureidopropyltrimethoxysilane and 3-ureidopropyltriethoxysilane.

[0202] As R A Examples of the compound C1 which is an epoxy group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane.

[0203] As RA Examples of the compound C1 which is a monovalent substituent having one or more reactive groups F1 include 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propyltriethoxysilane, 3-(2-aminoethylamino)propyldimethoxymethylsilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and compounds represented by the following formulae (1-1) to (1-9).

[0204] [Chemical formula 3]

[0205]

[0206] [Chemical formula 4]

[0207]

[0208] (1-1): N,N'-bis(2-aminoethyl)-6-(3-trihydroxysilylpropyl)amino-1,3,5-triazine-2,4-diamine

[0209] (1-2): N,N'-bis(2-aminoethyl)-6-(3-trimethoxysilylpropyl)amino-1,3,5-triazine-2,4-diamine

[0210] (1-3): N,N'-bis(2-aminoethyl)-6-(3-triethoxysilylpropyl)amino-1,3,5-triazine-2,4-diamine

[0211] (1-4): N,N'-bis(2-aminomethyl)-6-(3-trihydroxysilylpropyl)amino-1,3,5-triazine-2,4-diamine

[0212] (1-5): N,N'-bis(2-aminomethyl)-6-(3-trimethoxysilylpropyl)amino-1,3,5-triazine-2,4-diamine

[0213] (1-6): N,N'-bis(2-aminomethyl)-6-(3-triethoxysilylpropyl)amino-1,3,5-triazine-2,4-diamine

[0214] (1-7): 6-(3-trihydroxysilylpropyl)amino-1,3,5-triazine-2,4-diazide

[0215] (1-8): 6-(3-trimethoxysilylpropyl)amino-1,3,5-triazine-2,4-diazide

[0216] (1-9): 6-(3-triethoxysilylpropyl)amino-1,3,5-triazine-2,4-diazide

[0217] Compound C1 is preferably a compound represented by the above formulae (1-1) to (1-9), and more preferably a compound represented by formula (1-1) or (1-9).

[0218] (Method for producing pervaporation membrane)

[0219] The pervaporation membrane 10 can be manufactured, for example, by the following method. Figure 1B As shown, a separation functional layer 1 is made on a release liner 12. The separation functional layer 1 can be made by applying a coating liquid containing a material of the separation functional layer 1 on the release liner 12 and curing the obtained coating film. The coating liquid is, for example, a silicone resin composition or a (meth) acrylic resin composition. The curing of the coating film can be carried out at room temperature or in a heated environment. The curing of the coating film can also be carried out by irradiation with active energy rays such as UV. It should be noted that the curing of the coating film can also be carried out in a state where the coating film is sandwiched between two release liners 12.

[0220] When the coating film is cured by heating, the heating conditions of the coating film are not particularly limited. For example, the heating temperature of the coating film may be above 80°C, above 90°C, above 100°C, or above 120°C. The higher the heating temperature of the coating film, the more fully the curing reaction of the components in the resin composition proceeds. The upper limit of the heating temperature of the coating film is not particularly limited, for example, 200°C. The heating time of the coating film can be appropriately adjusted according to the composition of the resin composition used.

[0221] The surface 1a of the separation functional layer 1 may also be subjected to a surface modification treatment. Examples of the surface modification treatment include corona treatment, plasma treatment, excimer treatment, flame treatment, and the like, preferably corona treatment. The surface modification treatment is performed, for example, by irradiating the surface 1a of the separation functional layer 1 with active energy rays. Specific examples of active energy rays include electron beams, ion beams, plasma beams, ultraviolet rays, and the like.

[0222] As the release liner 12, for example, films containing resins; paper; sheets containing metal materials such as aluminum and stainless steel, etc. can be cited. Sheets containing metal materials tend to have high heat resistance. From the perspective of excellent surface smoothness, the release liner 12 is preferably a film containing resins. In the release liner 12, as polymers contained in the resin, polyolefins such as polyethylene, polypropylene, polybutene, polybutadiene, and polymethylpentene can be cited; polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyvinyl chloride, vinyl chloride copolymers; polyurethanes; ethylene-vinyl acetate copolymers, etc. are preferred, and polyethylene terephthalate is particularly preferred.

[0223] The surface of the release liner 12 may be subjected to a release treatment. The release treatment can be performed, for example, by applying a release treatment agent to the surface of the release liner 12. Examples of the release treatment agent include silicone-based release treatment agents, long-chain alkyl-based release treatment agents, fluorine-based release treatment agents, and molybdenum sulfide-based release treatment agents. The release treatment agent may be used alone or in combination of two or more. The release liner 12 is preferably a film made of polyethylene terephthalate (PET) subjected to a release treatment.

[0224] The thickness of the release liner 12 is not particularly limited, and is, for example, 5 to 100 μm, and preferably 10 to 50 μm.

[0225] Next, a molecular binder (coating liquid) containing the above-mentioned compound C1 is prepared. The molecular binder is coated on the surface A1 of the porous support 5. As a result, the reactive groups F1 and F2 of the compound C1 react with the surface A1 of the porous support 5 (specifically, the hydroxyl groups present on the surface A1). By reacting the compound C1 with the surface A1, the compound C1 is bonded to the surface A1. In this state, the reactive group F2 is present on the surface A1. That is, by processing based on the molecular binder, the reactive group F2 can be introduced into the surface A1 of the porous support 5.

[0226] Next, the porous support 5 is disposed on the separation functional layer 1 so that the surface A1 of the porous support 5 coated with the molecular binder is in contact with the separation functional layer 1 ( Figure 1C ), and then heat-dried. Thus, the reactive groups F2 present on the surface A1 react with the resin (especially silicone resin) contained in the separation function layer 1.

[0227] The drying temperature of the molecular binder is, for example, 40 to 150° C., and may be 60° C. or higher, or 70° C. or higher. The drying temperature of the molecular binder may be 150° C. or lower, or 90° C. or lower.

[0228] It should be noted that the heat drying of the molecular binder can be performed at the stage where the molecular binder is coated on the surface A1 of the porous support 5. In this case, the process of coating the molecular binder and drying it can be repeated multiple times. Thus, the density of the reactive groups F2 in the surface A1 can be increased. When the above process is repeated multiple times, different types of molecular binders can be used according to the process.

[0229] As another example, when the reactive group F1 is an azido group, there is a tendency that the reaction between the reactive group F1 and the surface A1 of the porous support 5 is likely to proceed by irradiating the surface A1 with ultraviolet rays.

[0230] After the reactive group F2 is reacted with the resin, the release liner 12 is removed to obtain the pervaporation membrane 10 .

[0231] It should be noted that, depending on the composition of the separation functional layer 1, the adhesion between the separation functional layer 1 and the porous support 5 is sometimes sufficiently large even without treating the surface A1 of the porous support 5 with a molecular binder. For example, when the separation functional layer 1 contains a (meth)acrylic resin, the peel strength between the separation functional layer 1 and the porous support 5 tends to be easily adjusted to 0.15 N / 20 mm or more even without using a molecular binder.

[0232] (Application of Pervaporation Membrane)

[0233] The permeation vaporization membrane 10 of the present embodiment is suitable for use, for example, in separating organic compound C from an aqueous solution S containing volatile organic compound C. The organic compound C is not particularly limited as long as it is volatile. In this specification, the so-called "volatile organic compound" refers to an organic compound having a boiling point of 20°C to 260°C at atmospheric pressure (101.325 kPa). It should be noted that, when the concentration of organic compound C in an aqueous solution is high, for example, an aqueous phase containing water as the main component and an organic phase having a higher content of organic compound C than the aqueous phase are generated. However, the organic compound C may not generate an aqueous phase and an organic phase.

[0234] The number of carbon atoms in the organic compound C is not particularly limited, and may be, for example, 10 or less, 8 or less, 6 or less, or 4 or less. The lower limit of the number of carbon atoms in the organic compound C may be 1 or 2. The organic compound C may have, for example, a functional group containing an oxygen atom such as a hydroxyl group, a carbonyl group, an ether group, or an ester group. In the organic compound C, the number of functional groups containing an oxygen atom is typically 1.

[0235] As the organic compound C, for example, alcohol, ketone, ester, etc. can be mentioned, typically alcohol. Alcohol can be an alkyl alcohol consisting of only an alkyl group and a hydroxyl group, or an aryl alcohol containing an aryl group and a hydroxyl group. The alkyl alcohol can be any of linear, branched, and cyclic. As the alkyl alcohol, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, isobutanol, tert-butanol, n-pentanol, etc. can be mentioned. As the aryl alcohol, for example, phenol, etc. can be mentioned.

[0236] The ketone may be a dialkyl ketone consisting only of an alkyl group and a carbonyl group. Examples of the dialkyl ketone include methyl ethyl ketone (MEK) and acetone.

[0237] The ester may be a fatty acid alkyl ester consisting only of an alkyl group and an ester group. Examples of the fatty acid alkyl ester include ethyl acetate and the like.

[0238] It should be noted that the organic compound C is not limited to the above compounds and may be an aromatic hydrocarbon such as benzene, toluene, or xylene.

[0239] The aqueous solution S may contain one organic compound C, or may contain two or more organic compounds C. The content of the organic compound C in the aqueous solution S is, for example, 0.5 wt% or more, 1 wt% or more, 2 wt% or more, or 5 wt% or more. The upper limit of the content of the organic compound C is not particularly limited, and is, for example, 50 wt%.

[0240] The organic compound C may be a fermentation product produced by microorganisms fermenting carbon sources, or may be an alcohol (bioalcohol) produced by microorganisms. That is, the aqueous solution S may be a fermentation liquid containing the organic compound C as a fermentation product. However, the aqueous solution S is not limited to the fermentation liquid, and may also be waste liquid or wastewater discharged from chemical equipment, etc.

[0241] The aqueous solution S may contain other components such as microorganisms that generate fermentation products, carbon sources, nitrogen sources, and inorganic ions in addition to water and organic compounds C. The microorganisms that generate fermentation products are typically bacteria. As carbon sources, polysaccharides such as starch and monosaccharides such as glucose may be cited.

[0242] (Pervaporation membrane characteristics)

[0243] The separation coefficient of organic compound C relative to water in pervaporation membrane 10 is not particularly limited. As an example, the separation coefficient α of n-butanol (BuOH) relative to water in pervaporation membrane 10 is, for example, 10 or more, and may be 15 or more, 20 or more, 25 or more, 30 or more, or 40 or more. The upper limit of the separation coefficient α is, for example, 100.

[0244] The separation coefficient α can be measured by the following method. While a mixed liquid obtained from BuOH and water is in contact with one side of the pervaporation membrane 10 (e.g., the main surface 10a on the separation functional layer side of the pervaporation membrane 10), the space adjacent to the other side of the pervaporation membrane 10 (e.g., the main surface 10b on the porous support body side of the pervaporation membrane 10) is depressurized. Thus, a permeating fluid passing through the pervaporation membrane 10 is obtained. The weight ratio of water and the weight ratio of BuOH in the permeating fluid are measured. In the above operation, the content of BuOH in the mixed liquid is 1.0 wt%. The temperature of the mixed liquid in contact with the pervaporation membrane 10 is 30°C. The space adjacent to the other side of the pervaporation membrane 10 is depressurized to 15 hPa. The separation coefficient α can be calculated according to the following formula. Wherein, in the following formula, X A and X B are the weight ratio of BuOH and the weight ratio of water in the mixed liquid respectively. A and Y BThey are the weight ratio of BuOH and the weight ratio of water in the permeated fluid that has permeated the pervaporation membrane 10 .

[0245] Separation coefficient α=(Y A / Y B ) / (X A / X B )

[0246] In the measurement conditions of the separation coefficient α, the flux of BuOH passing through the pervaporation membrane 10 is not particularly limited, and is, for example, 0.01 (g / min / m 2 )~10.0(g / min / m 2 )(i.e., 0.0006(kg / m 2 / hr)~0.6(kg / m 2 / hr)).

[0247] In the past, a pervaporation membrane was produced by coating a coating liquid containing a material of a separation functional layer on a porous support and drying the obtained coating film. At this time, in order to prevent the coating liquid from penetrating into the interior of the porous support, the average diameter of the openings on the surface of the porous support opposite to the separation functional layer tends to be adjusted to a lower value. As an example, a laminated body in which a microporous layer having an average diameter of openings smaller than that of the main body is arranged on a main body such as a fiber structure is used as a porous support to produce a pervaporation membrane (for example, Patent Document 1).

[0248] On the other hand, in the pervaporation membrane 10 of the present embodiment, the average diameter L1 of the openings H1 in the surface A1 of the porous support 5 is adjusted to be 0.5 μm or more. The pervaporation membrane 10 tends to have good separation performance (particularly, the flux of the permeated fluid passing through the pervaporation membrane) due to the large average diameter L1 of the openings H1.

[0249] <Embodiment of membrane separation device>

[0250] like Figure 2 As shown, the membrane separation device 20 of this embodiment includes a pervaporation membrane 10 and a tank 22. The tank 22 has a first chamber 23 and a second chamber 24. The first chamber 23 functions as a supply space to which a supply fluid (specifically, the above-mentioned aqueous solution S) is supplied. The second chamber 24 functions as a permeation space to which a permeated fluid S1 is supplied. The permeated fluid S1 is obtained by the aqueous solution S permeating the pervaporation membrane 10.

[0251] Pervaporation membrane 10 is disposed inside tank 22. Pervaporation membrane 10 partitions first chamber 23 and second chamber 24 inside tank 22. Pervaporation membrane 10 extends from one of a pair of wall surfaces of tank 22 to the other.

[0252] The first chamber 23 has an inlet 23a and an outlet 23b. The second chamber 24 has an outlet 24a. The inlet 23a is an opening for supplying the aqueous solution S to the supply space (the first chamber 23). The outlet 24a is an opening for discharging the permeated fluid S1 from the permeation space (the second chamber 24). The outlet 23b is an opening for discharging the aqueous solution S (non-permeated fluid S2) that has not permeated the permeation vaporization membrane 10 from the supply space (the first chamber 23). Each of the inlet 23a, the outlet 23b, and the outlet 24a is formed, for example, on the wall surface of the tank 22.

[0253] The membrane separation device 20 is suitable for a flow-through (continuous) membrane separation method. However, the membrane separation device 20 can also be used for a batch-type membrane separation method.

[0254] (Method for operating membrane separation device)

[0255] The operation method of membrane separation device 20 is implemented as follows, for example. First, aqueous solution S is supplied to first chamber 23 of membrane separation device 20 through inlet 23a. Thus, aqueous solution S can be brought into contact with one surface (for example, main surface 10a) of pervaporation membrane 10.

[0256] Next, while the aqueous solution S is in contact with one side of the pervaporation membrane 10, the space adjacent to the other side (e.g., the main side 10b) of the pervaporation membrane 10 is decompressed. Specifically, the pressure in the second chamber 24 is reduced through the outlet 24a. The decompression in the second chamber 24 can be performed, for example, by a decompression device such as a vacuum pump. The pressure in the second chamber 24 is, for example, 50 kPa or less, and can be 20 kPa or less, 10 kPa or less, 5 kPa or less, 3 kPa or less, or 2 kPa or less. It should be noted that, in this specification, "pressure" refers to absolute pressure unless otherwise specified.

[0257] By reducing the pressure in the second chamber 24, a permeated fluid S1 having a high content of organic compound C can be obtained on the other side of the pervaporation membrane 10. In other words, the permeated fluid S1 is supplied to the second chamber 24. In the second chamber 24, the permeated fluid S1 is typically a gas. The permeated fluid S1 is discharged to the outside of the membrane separation device 20 through the outlet 24a.

[0258] On the other hand, the content of the organic compound C in the aqueous solution S gradually decreases from the inlet 23a to the outlet 23b of the first chamber 23. The aqueous solution S (non-permeable fluid S2) treated in the first chamber 23 is discharged to the outside of the membrane separation device 20 through the outlet 23b. The non-permeable fluid S2 is typically a liquid.

[0259] As described above, pervaporation membrane 10 can preferentially permeate organic compounds C contained in aqueous solution S. Therefore, permeated fluid S1 obtained by operating membrane separation device 20 has a higher content of organic compounds C than aqueous solution S supplied to membrane separation device 20 .

[0260] <Modification of membrane separation device>

[0261] The membrane separation device 20 may be a spiral membrane element, a hollow fiber membrane element, a coil-type membrane element in which a plurality of pervaporation membranes are stacked, a plate-and-frame membrane element, or the like. Figure 3 A spiral type membrane element is shown. Figure 3 The membrane separation device 25 includes a central tube 26 and a stack 27 . The stack 27 includes a pervaporation membrane 10 .

[0262] The central tube 26 has a cylindrical shape. A plurality of holes or slits are formed on the surface of the central tube 26 for allowing the permeating fluid S1 to flow into the interior of the central tube 26. Examples of the material of the central tube 26 include resins such as acrylonitrile-butadiene-styrene copolymer resin (ABS resin), polyphenylene ether resin (PPE resin), and polysulfone resin (PSF resin); and metals such as stainless steel and titanium. The inner diameter of the central tube 26 is, for example, in the range of 20 to 100 mm.

[0263] Laminated body 27 includes, in addition to pervaporation membrane 10, feed-side flow path material 28 and permeate-side flow path material 29. Laminated body 27 is wound around core tube 26. Membrane separation device 25 may further include an exterior material (not shown).

[0264] As the supply side flow path material 28 and the permeate side flow path material 29, for example, a net, woven fabric or knitted fabric made of a resin obtained from polyethylene, polypropylene, polyethylene terephthalate (PET), polyphenylene sulfide (PPS) or ethylene-chlorotrifluoroethylene copolymer (ECTFE) can be used.

[0265] The membrane separation device 25 can be operated, for example, by the following method. First, the aqueous solution S is supplied to one end of the wound stack 27. The internal space of the central tube 26 is depressurized. As a result, the permeated fluid S1 that has permeated the pervaporation membrane 10 of the stack 27 moves into the interior of the central tube 26. The permeated fluid S1 passes through the central tube 26 and is discharged to the outside. The aqueous solution S (non-permeated fluid S2) treated in the membrane separation device 25 is discharged to the outside from the other end of the wound stack 27.

[0266] <Embodiment of membrane separation system>

[0267] like Figure 4As shown in FIG. 1 , the membrane separation system 100 of the present embodiment includes the membrane separation device 20 described above. Figure 3 The membrane separation device 25 described above is used instead of the membrane separation device 20.

[0268] The membrane separation system 100 further includes a membrane separation device 20 and a tank 30. The tank 30 stores an aqueous solution S to be supplied to the membrane separation device 20. The tank 30 may be a fermentation tank for producing an organic compound C by fermentation of a carbon source by microorganisms.

[0269] The membrane separation system 100 further includes an aqueous solution supply path 70, a non-permeated fluid discharge path 71, and a permeated fluid discharge path 72. The aqueous solution supply path 70 is a path for supplying the aqueous solution S from the tank 30 to the membrane separation device 20 during operation, and is connected to the outlet 31 of the tank 30 and the inlet 23a of the membrane separation device 20. The aqueous solution supply path 70 is provided with, for example, a pump 50 for controlling the flow rate of the aqueous solution S.

[0270] The non-permeated fluid discharge path 71 is a path for discharging the non-permeated fluid S2 from the membrane separation device 20 during operation, and is connected to the outlet 23b of the membrane separation device 20. For example, a pump 51 for controlling the flow rate of the non-permeated fluid S2 is arranged in the non-permeated fluid discharge path 71. It should be noted that the pump 51 may not be arranged in the non-permeated fluid discharge path 71. The non-permeated fluid discharge path 71 may be connected to the inlet 32 ​​of the tank 30, and may be configured so that the non-permeated fluid S2 is delivered to the tank 30 during operation. That is, during operation, the non-permeated fluid S2 may be mixed with the aqueous solution S in the tank 30 and circulated in the aqueous solution supply path 70 and the non-permeated fluid discharge path 71. When the non-permeated fluid S2 is delivered to the tank 30, the aqueous solution S and the non-permeated fluid S2 are mixed in the tank 30, and the content rate of the organic compound C in the aqueous solution S is reduced. When the tank 30 is a fermentation tank, the fermentation stop by the microorganisms can be suppressed by reducing the content rate of the organic compound C in the aqueous solution S, thereby continuously producing the fermented product.

[0271] The permeate fluid discharge path 72 is a path for discharging the permeate fluid S1 from the membrane separation device 20 during operation, and is connected to the outlet 24a of the membrane separation device 20. For example, a decompression device 52 is arranged in the permeate fluid discharge path 72. The decompression device 52 can reduce the pressure in the permeate space of the membrane separation device 20. The decompression device 52 is preferably a vacuum device such as a vacuum pump. The vacuum pump is typically a gas-transporting vacuum pump, and a reciprocating vacuum pump, a rotary vacuum pump, etc. can be cited. As a reciprocating vacuum pump, a diaphragm type and a swing piston type vacuum pump can be cited. As a rotary vacuum pump, there can be cited: a liquid seal pump; an oil rotary pump (rotary pump); a mechanical booster pump; various dry pumps such as roots type, claw type, screw type, turbine type, and vortex type. The pump as the decompression device 52 can also be provided with a variable speed mechanism for changing the rotation speed, etc. An example of a variable speed mechanism is an inverter that drives the motor of the pump. By controlling the rotation speed of the pump, etc. using a variable speed mechanism, the pressure of the permeate space of the membrane separation device 20 can be appropriately adjusted.

[0272] A heat exchanger for cooling the permeated fluid S1 may be further arranged in the permeated fluid discharge path 72. The gas permeated fluid S1 can be condensed by the heat exchanger. The heat exchanger is, for example, a gas-liquid heat exchanger that performs heat exchange between a cooling medium such as an antifreeze liquid and the gas permeated fluid S1. The heat exchanger may be located between the membrane separation device 20 and the pressure reducing device 52 (on the upstream side of the pressure reducing device 52), or between the pressure reducing device 52 and the recovery unit 40 described later (on the downstream side of the pressure reducing device 52).

[0273] The membrane separation system 100 further includes a recovery unit 40. The recovery unit 40 recovers the permeated fluid S1 sent from the membrane separation device 20 and can store the permeated fluid S1. The recovery unit 40 is, for example, a tank storing the permeated fluid S1. The inlet 41 of the recovery unit 40 is connected to a permeated fluid discharge path 72.

[0274] The membrane separation system 100 may further include a controller 60 for controlling the various components of the membrane separation system 100. The controller 60 is, for example, a DSP (Digital Signal Processor) including an A / D conversion circuit, an input / output circuit, an operation circuit, a storage device, etc. The controller 60 stores a program for properly operating the membrane separation system 100.

[0275] Unless otherwise specified, each path of the membrane separation system 100 is constituted by, for example, a pipe made of metal or resin.

[0276] Example

[0277] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[0278] (Example 1)

[0279] First, 54 g of toluene (manufactured by FUJIFILM Wako Pure Chemical Corporation, special grade) as a diluent solvent and 1 g of a platinum catalyst (manufactured by Shin-Etsu Chemical Co., Ltd., CAT-PL-50T) as a curing catalyst were added to 100 g of a silicone resin composition (manufactured by Shin-Etsu Chemical Co., Ltd., KS-847T, toluene solution, solid content 30 wt%) to prepare a coating liquid (addition type silicone resin composition). Next, a coating film (thickness 500 μm) was obtained by coating the coating liquid on a release liner (manufactured by Mitsubishi Chemical Corporation, DIAFOIL MRE38). Next, the coating film was heated at 90°C for 20 minutes to cure it, thereby preparing a separation functional layer with a thickness of 50 μm. The surface of the separation functional layer prepared was subjected to corona treatment. The corona treatment was carried out at an output power of 0.16 kW, a worktable moving speed of 3 m / min, and a discharge amount of 200 W·min / m 2 implemented under the conditions of.

[0280] Next, a PET nonwoven fabric is prepared as a porous support. An aqueous solution containing a molecular bonding compound (manufactured by Sulfur Chemical Laboratory Inc., N,N'-bis(2-aminoethyl)-6-(3-trihydroxysilylpropyl)amino-1,3,5-triazine-2,4-diamine) at a content of 0.5wt% is applied to the surface of the porous support, and the porous support is arranged on the separation functional layer in such a manner that the surface treated with the aqueous solution is in contact with the separation functional layer, and heated at 90°C for 10 minutes. Thus, the surface of the porous support is bonded to the silicone resin contained in the separation functional layer via the molecular bonding compound. The permeation vaporization membrane of Example 1 is obtained by removing the release liner.

[0281] (Example 2)

[0282] First, as a porous support, a laminate of a microporous layer made of polysulfone and a nonwoven fabric made of PET is prepared. Then, 50 g of a silicone resin composition (KE-1935B made by Shin-Etsu Chemical Co., Ltd.) is added to 50 g of a silicone resin composition (KE-1935A made by Shin-Etsu Chemical Co., Ltd.) to prepare a coating liquid (addition type silicone resin composition). The coating liquid is a solvent-free type that does not contain a solvent. Next, a coating film (thickness 70 μm) is obtained by applying the coating liquid on the microporous layer of the porous support.

[0283] Next, the coating film was heated at 150° C. for 10 minutes to cure, thereby producing a separation functional layer having a thickness of 50 μm. Thus, a pervaporation membrane of Example 2 was obtained.

[0284] (Example 3)

[0285] First, as a porous support, RS-50 (a laminate of a PVDF microporous layer and a PET nonwoven fabric) manufactured by Nitto Denko Corporation was prepared. Next, 54 g of toluene (special grade manufactured by FUJIFILM Wako Pure Chemical Corporation) as a diluent and 1 g of a platinum catalyst (CAT-PL-50T manufactured by Shin-Etsu Chemical Co., Ltd.) as a curing catalyst were added to 100 g of a silicone resin composition (KS-847T manufactured by Shin-Etsu Chemical Co., Ltd.) to prepare a coating liquid (addition type silicone resin composition). The coating liquid was applied onto the microporous layer of the porous support to obtain a coating film (thickness 500 μm).

[0286] Next, the coated film was heated at 90° C. for 20 minutes to be cured, thereby producing a separation functional layer having a thickness of 50 μm. Thus, a pervaporation membrane of Example 3 was obtained.

[0287] (Example 4)

[0288] First, 1.8 g of silica filler (AEROSIL RX200, manufactured by Nippon Aerosil Co., Ltd.) was added to 18.2 g of 2-ethylhexyl acrylate (2EHA, manufactured by TOAGOSEI CO., LTD.), and stirred (2000 rpm, 3 minutes) and degassed (2200 rpm, 1 minute) using Awatori Rentaro manufactured by Thinky Corporation. Next, 0.017 g of 1,6-hexanediol diacrylate (manufactured by OSAKA ORGANIC CHEMICAL INDUSTRY LTD.) was added as a crosslinking agent, and stirred (2000 rpm, 1 minute) and degassed (2200 rpm, 1 minute). Furthermore, 0.017 g of 1-hydroxycyclohexyl phenyl ketone (Omnirad184, manufactured by IGM Resins BV) was added as a photopolymerization initiator, and stirred (2000 rpm, 3 minutes) and degassed (2200 rpm, 1 minute) to prepare a coating liquid (acrylic resin composition).

[0289] Next, the coating liquid was applied between two release liners (DIAFOIL MRE38, MRF38 manufactured by Mitsubishi Chemical Corporation) to produce a coating film sandwiched between the two release liners. The coating liquid was applied by an applicator so that the thickness of the coating film was about 20 μm. Next, UV was irradiated from the release liner (MRF38) side on one side to cure the coating film, thereby producing a separation functional layer. UV irradiation was performed using a black light lamp at an illumination of 2.5 mW / cm 2 、Discharge 2400mJ / cm 2 The distance between the black light lamp and the surface of the coating film was adjusted to 30 mm.

[0290] After the separation functional layer was prepared, the release liner (MRE38) on one side was peeled off to expose the surface of the separation functional layer. The exposed surface of the separation functional layer was overlapped with the porous support, and a 2 kg roller was reciprocated once to press them together. As the porous support, a PTFE stretched porous membrane (NTF1122 manufactured by Nitto Denko Corporation) was used. Then, the release liner (MRF38) on the other side was removed to obtain the pervaporation membrane of Example 4.

[0291] (Example 5)

[0292] As the porous support, RS-50 (a laminate of a PVDF microporous layer and a PET nonwoven fabric) manufactured by Nitto Denko Corporation was used, and the surface of the porous support on the PVDF microporous layer side was overlapped with the separation functional layer. The permeation vaporization membrane of Example 5 was obtained by the same method as Example 4, except that the above-mentioned method was repeated.

[0293] [Gerlai air permeability]

[0294] The Gurley air permeability of the porous support used for producing the pervaporation membrane was measured by a method in accordance with the air permeability measurement method B (Gurley method) specified in JIS L1096:2010.

[0295] [Aperture ratio]

[0296] For the porous support used for producing the pervaporation membrane, the opening ratio R1 of the surface A1 facing the separation functional layer and the opening ratio R2 of the surface A2 facing the surface A1 were measured by the above-mentioned method.

[0297] [Average diameter]

[0298] For the porous support used to produce the pervaporation membrane, the average diameter L1 of the openings in the surface A1 facing the separation functional layer and the average diameter L2 of the openings in the surface A2 facing the surface A1 were determined by the above method.

[0299] [Peel strength]

[0300] The above test was performed on the produced pervaporation membrane to measure the peel strength. As a tensile testing machine, Autograph AGS-50NX manufactured by Shimadzu Corporation was used. It should be noted that, for Example 1, the separation functional layer was sufficiently fixed to the porous support body, and the separation functional layer could not be peeled off from the porous support body by hand. When it was attempted to be forcibly peeled off, the separation functional layer broke. Therefore, for Example 1, the fracture strength of the separation functional layer was measured by the above method. As described above, the peel strength can be regarded as a value above the fracture strength.

[0301] In the pervaporation membranes of Examples 4 and 5, the separation functional layer was soft and difficult to be directly held by the chuck. Therefore, for these membranes, the peel strength was measured by the above-mentioned method using an evaluation sheet (PET film).

[0302] [PV performance]

[0303] The separation coefficient α of n-butanol (BuOH) relative to water was measured for the produced pervaporation membrane by the following method. First, the pervaporation membrane was cut into a size of 74 mm in diameter to form a flat film test piece. The test piece was placed in an intermittent membrane separation device (unit). A mixed liquid obtained by n-butanol (BuOH) and water was supplied to the supply space of the unit. The content of BuOH in the mixed liquid was 1.0 wt%.

[0304] Next, the unit was immersed in a water bath, and the temperature of the mixed liquid was adjusted to 30°C. Next, the mixed liquid was stirred using a stirrer disposed in the unit while the pressure in the permeation space was reduced to 15 hPa. Thus, the mixed liquid passed through the permeation vaporization membrane to obtain a gaseous permeation fluid. The gaseous permeation fluid was cooled by using a cooling trap of liquid nitrogen to condense the permeation fluid. The composition of the liquid permeation fluid was analyzed by gas chromatography, and based on the results obtained, the separation coefficient α and the flux of BuOH permeating the permeation vaporization membrane (kg / m 2 / hr).

[0305] [Table 1]

[0306]

[0307] [Table 2]

[0308]

[0309] The abbreviations in Tables 1 and 2 are as follows.

[0310] KS847T: Silicone resin composition (manufactured by Shin-Etsu Chemical Co., Ltd., KS-847T)

[0311] KE1935: Silicone resin composition (manufactured by Shin-Etsu Chemical Co., Ltd., KE-1935)

[0312] RX200: silica filler (manufactured by Japan Aerosil Co., Ltd., AEROSIL RX200, surface modification group: trimethylsilane (TMS) group)

[0313] As can be seen from Table 1, in Example 1, the average diameter L1 of the openings in the surface A1 of the porous support body opposite to the separation functional layer is 0.5 μm or more. Furthermore, the peel strength between the separation functional layer and the porous support body is 0.15 N / 20 mm or more. Compared with Examples 2 and 3, the PV performance of the pervaporation membrane of Example 1 is good.

[0314] In addition, as can be seen from Table 2, in Example 4, the average diameter L1 of the openings in the surface A1 of the porous support body opposite to the separation functional layer is 0.5 μm or more. Furthermore, the peel strength between the separation functional layer and the porous support body is 0.15 N / 20 mm or more. Compared with Example 5, the PV performance of the pervaporation membrane of Example 4 is good.

[0315] Industrial Applicability

[0316] The pervaporation membrane of the present embodiment is suitable for separating volatile organic compounds from an aqueous solution containing the organic compounds.

Claims

1. A permeation vaporization membrane having: separating the functional layers; and a porous support for supporting the separation functional layer, The porous support has a surface A1 facing the separation functional layer and including a plurality of openings H1. The average diameter L1 of the plurality of openings H1 is 0.5 μm or more. The peel strength measured by the following test is 0.15N / 20mm or more, Test: The pervaporation membrane was cut into a test piece of 20 mm in width and 150 mm in length. The separation functional layer was peeled off from the porous support using the test piece at a peeling angle of 180° and a tensile speed of 300 mm / min.

2. The pervaporation membrane according to claim 1, wherein: The porous support has a surface A2 that is opposite to the surface A1 and includes a plurality of openings H2. The average diameter L2 of the plurality of openings H2 is greater than or equal to 0.5 μm.

3. The pervaporation membrane according to claim 1, wherein: The porous support is a fiber structure.

4. A permeation vaporization membrane having: separating the functional layers; and a porous support body, which is in direct contact with the separation functional layer and supports the separation functional layer; The porous support is a fiber structure.

5. The pervaporation membrane according to claim 3 or 4, wherein: The fiber structure is a nonwoven fabric or a stretched porous film containing fibrils.

6. The pervaporation membrane according to claim 1 or 4, wherein: The air permeability of the porous support in the thickness direction is 50 sec / 100 mL or less, as represented by air permeability determined by air permeability measurement method B (Gurley method) specified in JIS L1096:2010.

7. The pervaporation membrane according to claim 1 or 4, wherein: The separation function layer includes a silicone resin.

8. The pervaporation membrane according to claim 7, wherein: The porous support has a surface A1 that faces the separation functional layer and is treated with a molecular bonding agent. The molecular binder includes a compound having a reactive group F1 capable of reacting with the surface A1 and a reactive group F2 capable of reacting with the silicone resin contained in the separation function layer.

9. The pervaporation membrane according to claim 1 or 4, wherein: The separation function layer includes a (meth)acrylic resin.

10. The pervaporation membrane according to claim 1 or 4, wherein: The separation function layer contains a filler.

11. The pervaporation membrane according to claim 10, wherein: The filler includes at least one selected from the group consisting of zeolite and silica.

12. The pervaporation membrane according to claim 1 or 4, which is used for separating volatile organic compounds from an aqueous solution containing the organic compounds.

13. The pervaporation membrane according to claim 12, wherein: The organic compound is a fermentation product produced by microorganisms.

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