WO2016117360A1

WO2016117360A1 - Acidic gas separation module

Info

Publication number: WO2016117360A1
Application number: PCT/JP2016/050273
Authority: WO
Inventors: 岳史成田; 大介平木
Original assignee: 富士フイルム株式会社
Priority date: 2015-01-22
Filing date: 2016-01-06
Publication date: 2016-07-28
Also published as: JPWO2016117360A1

Abstract

An acidic gas separation module having: an acidic gas separation membrane having a facilitated transport membrane and a carrier diffusion suppression layer that prevents diffusion of a facilitated transport membrane carrier, said facilitated transport membrane containing a porous substrate, a carrier that reacts with acidic gas, and a hydrophilic compound for supporting the carrier; and a member for a feed gas flow path forming a flow path for raw material gas. The carrier diffusion suppression layer includes a fluorine-modified silicone compound and the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer is 5%-40%. As a result, an acidic gas separation module having good durability is provided.

Description

Acid gas separation module

The present invention relates to an acid gas separation module that separates an acid gas from a raw material gas using a facilitated transport membrane. Specifically, the present invention relates to an acidic gas separation module having good durability.

In recent years, development of technology for selectively separating acid gas from source gas (treated gas) has been progressing. For example, an acidic gas separation module that separates an acidic gas from a raw material gas using an acidic gas separation membrane that selectively permeates the acidic gas has been developed.

As an example, Patent Document 1 includes a carbon dioxide carrier on a carbon dioxide permeable support as an acidic gas separation membrane (carbon dioxide separation gel membrane) for separating carbon dioxide (carbon dioxide) from a raw material gas. An acidic gas separation membrane having a hydrogel membrane formed by absorbing an aqueous solution into a vinyl alcohol-acrylate copolymer having a crosslinked structure is disclosed.
Further, in Patent Document 1, as a method for producing this acidic gas separation membrane, an uncrosslinked vinyl alcohol-acrylate copolymer aqueous solution is coated on a carbon dioxide permeable support in the form of a membrane, A method for producing an acidic gas separation membrane is also disclosed in which an aqueous solution is heated and cross-linked to insolubilize water, and the water-insolubilized material absorbs a carbon dioxide carrier aqueous solution and gels.

The acid gas separation membrane shown in Patent Document 1 is an acid gas separation membrane using a so-called facilitated transport membrane. The facilitated transport membrane has a carrier that reacts with an acidic gas such as the above-mentioned carbon dioxide carrier in the membrane, and the acidic gas is separated from the source gas by transporting the acidic gas to the opposite side of the membrane by this carrier. .

Such an acid gas separation membrane usually has a configuration in which a facilitated transport membrane is formed on a porous support such as a nonwoven fabric or a porous membrane.

Here, the facilitated transport film needs to retain a large amount of moisture in the film in order to sufficiently function the carrier. Therefore, a polymer having extremely high water absorption and water retention is used for the facilitated transport film. In addition, in the facilitated transport membrane, as the content of a carrier such as a metal carbonate increases, the water absorption increases and the separation performance of the acid gas improves. That is, the facilitated transport film is often a very soft (low viscosity), gel film.
In addition, in an acidic gas separation membrane using a facilitated transport membrane, a raw material gas having a temperature of 100 to 130 ° C. and a humidity of about 90% is supplied at a pressure of about 1.5 MPa when the acidic gas is separated.

Therefore, when an acid gas separation membrane using a facilitated transport membrane is used, the carrier gradually reaches the support from the facilitated transport membrane and permeates the support.
If the carrier flows out from the facilitated transport film, the acid gas separation performance is lowered accordingly. Therefore, the acid gas module using the facilitated transport membrane cannot be said to have sufficient durability.

In order to solve such problems, Patent Document 2 discloses that a facilitated transport film (polymer compound layer) is formed on a hydrophobic support (porous film) having a heat resistance of 100 ° C. or higher. In the acidic gas separation membrane, a carrier diffusion suppression layer is provided between the support and the facilitated transport membrane.
In Patent Document 2, siloxane, silicone rubber, polybutadiene, ethylcellulose, polyvinylidene fluoride, polypropylene, polysulfone, polyetherimide, polyethersulfite, polyacrylic acid, polyvinyl alcohol, etc. are exemplified as the material for forming the carrier diffusion suppressing layer. Has been. The thickness of the carrier diffusion suppressing layer is exemplified as 0.01 to 100 μm.

Furthermore, Patent Document 3 describes that an intermediate layer is formed on the support and the facilitated transport film is formed on the intermediate layer for the main purpose of preventing penetration of the facilitated transport film into the support. ing.
Examples of the material for forming the intermediate layer include organopolysiloxanes such as polydimethylsiloxane (PDMS), and modified silicones in which amino groups, epoxy groups, and alkyl halide groups are introduced into the side chains of the organopolysiloxane. Yes.

Japanese Patent Publication No. 7-102310 JP 2013-27841 A International Publication No. 2014/156192

As shown in Patent Document 2, by providing a carrier diffusion suppression layer on the surface of the support, it is possible to suppress the carriers that have escaped from the facilitated transport film from reaching the support and diffusing the carriers. Further, according to the study by the present inventors, the organopolysiloxane used as the intermediate layer in Patent Document 3 also has a function of suppressing the carrier that has escaped from the facilitated transport film from reaching the support and diffusing the carrier. Have

However, in recent years, the durability required for the acid gas separation module has become more severe, and the acid gas separation module with more durability, with fewer carriers passing through the support through the facilitated transport membrane. The appearance of is desired.

An object of the present invention is to solve such problems of the prior art, and is an acidic gas separation module using an acidic gas separation membrane having a facilitated transport membrane, in which the carrier leaves the facilitated transport membrane and the support. It is an object of the present invention to provide an acidic gas separation module with excellent durability, which can suitably suppress the diffusion.

In order to achieve this object, the acidic gas separation module of the present invention includes a porous support, a carrier that reacts with an acidic gas, and a facilitated transport membrane containing a hydrophilic compound for supporting the carrier, and a facilitated transport membrane. An acidic gas separation membrane having a carrier diffusion suppressing layer that prevents the carrier of the gas from diffusing, and a supply gas flow path member that becomes a flow path of the source gas,
An acidic gas separation module is provided in which the carrier diffusion suppressing layer contains a fluorine-modified silicone compound, and the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppressing layer is 5 to 40% in atomic ratio.

In such an acidic gas separation module of the present invention, the ratio of fluorine atoms to silicon atoms in the fluorine-modified silicone compound contained in the carrier diffusion suppressing layer is preferably 20 to 300% in terms of atomic ratio.
Moreover, it is preferable that the weight average molecular weight of a fluorine-modified silicone compound is 20000 or less.
The carrier is preferably an alkali metal compound.
Moreover, it is preferable that the carrier diffusion suppressing layer further contains an organopolysiloxane.
Moreover, it is preferable that it is a spiral type formed by winding the laminated body containing an acidic gas separation membrane and the member for supply gas flow paths.
Furthermore, it is preferable that the laminated body including the acidic gas separation membrane and the supply gas flow path member is a flat plate type that is maintained in a flat plate shape.

According to the present invention, in the acidic gas separation membrane using the facilitated transport membrane, the carrier is prevented from escaping through the facilitated transport membrane and further diffusing through the porous support. A gas separation module can be obtained.

It is a schematic perspective view which partially cuts off and shows an example of the acidic gas separation module of this invention. It is a schematic sectional drawing of a part of laminated body of the acidic gas separation module shown in FIG. It is a schematic sectional drawing of a part of acidic gas separation membrane of the acidic gas separation module shown in FIG. 4 (A) and 4 (B) are conceptual diagrams for explaining a method for producing the acidic gas separation module shown in FIG. It is a conceptual diagram for demonstrating the production method of the acidic gas separation module shown in FIG. 6 (A) and 6 (B) are conceptual diagrams for explaining a method for producing the acidic gas separation module shown in FIG. It is a conceptual diagram for demonstrating the production method of the acidic gas separation module shown in FIG. It is a conceptual diagram for demonstrating the production method of the acidic gas separation module shown in FIG.

Hereinafter, the acidic gas separation module of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 is a partially cutaway schematic perspective view of an example of the acid gas separation module of the present invention. In the following description, the acid gas separation module is also simply referred to as a separation module.
As shown in FIG. 1, the separation module 10 basically includes a central cylinder 12, a laminate wound product 14 obtained by winding a laminate 14 a having an acidic gas separation membrane 20, a telescope prevention plate 16, and the like. It is comprised. The laminated body 14 a is a laminated body including the acidic gas separation membrane 20, the supply gas flow path member 24, and the permeate gas flow path member 26. Furthermore, the acidic gas separation membrane 20 is composed of a facilitated transport membrane 20a, a porous support 20b, and a carrier diffusion suppression layer 20c.
As an example, the separation module 10 separates carbon dioxide as an acidic gas Gc from a raw material gas G containing carbon monoxide, carbon dioxide (CO ₂ ), water (water vapor), and hydrogen.

The separation module 10 in the illustrated example is a so-called spiral type separation module. Therefore, the separation module 10 stacks a plurality of sheet-like laminates 14a to be described later, and winds the laminate around the central cylinder 12 to form the laminate wound product 14. The telescoping prevention plate 16 is provided through the central tube 12 on both end surfaces of the lens. That is, the laminate wound product 14 is a substantially cylindrical product formed by the laminate 14a that is laminated and wound.
The outermost peripheral surface of the wound laminate 14 a is covered with a gas impermeable coating layer 18.

Note that the separation module of the present invention is not limited to the spiral type as shown in the drawings, and may be a so-called flat plate type in which the sheet-like laminate 14a is maintained in a flat plate shape.

In such a separation module 10, the raw material gas G from which the acidic gas is separated passes through the opening 16 d of the telescope prevention plate 16 on the back side in FIG. It is supplied inside the body 14a.
The source gas G supplied to the stacked body 14a is separated from the acidic gas Gc while flowing in the stacked body 14a.
The acidic gas Gc separated from the raw material gas G by the laminated body 14a is discharged from the central cylinder 12, and the raw material gas G from which the acidic gas has been separated (hereinafter referred to as residual gas Gr for convenience) It is discharged from the end surface opposite to the supply side of the roll 14, and is discharged to the outside of the separation module 10 through the opening 16 d of the telescope prevention plate 16.

The central tube (permeate gas collecting tube) 12 is a cylindrical tube whose end surface on the source gas G supply side is closed, and a plurality of through holes 12a are formed on the peripheral surface (tube wall).
The acidic gas Gc separated from the raw material gas G passes through a permeating gas passage member 26 described later, reaches the inside of the central cylinder 12 from the through hole 12a, and is discharged from the open end 12b of the central cylinder 12.

In the center tube 12, the aperture ratio is preferably 1 to 80%, more preferably 1 to 75%, and further preferably 1.5 to 70%. Among these, from the practical viewpoint, the opening ratio of the center tube 12 is particularly preferably 1.5 to 25%. Specifically, the opening ratio of the central cylinder 12 is an area ratio of the through-holes 12 a occupying the outer peripheral surface of the central cylinder 12 in the formation region of the through-holes 12 a in the length direction of the central cylinder 12.
By setting the aperture ratio of the center tube 12 within the above range, the acid gas Gc can be efficiently collected, and the strength of the center tube 12 can be increased to ensure sufficient processability.

The through hole 12a is preferably a circular hole having a diameter of 0.5 to 20 mm. Furthermore, it is preferable that the through holes 12 a are formed uniformly on the peripheral surface of the central cylinder 12.

The center tube 12 may be provided with a supply port (supply unit) for supplying a gas (sweep gas) for flowing the separated acidic gas Gc to the open end 12b side as necessary.
Furthermore, it is preferable that a slit (not shown) is provided on the peripheral surface of the center tube 12 along the axial direction. This slit will be described in detail later.

As described above, the laminate 14a is formed by laminating the acidic gas separation membrane 20, the supply gas flow path member 24, and the permeate gas flow path member 26.
Reference numeral 30 in FIG. 1 denotes an adhesive layer 30 that bonds the acidic gas separation membrane 20 and the permeate gas flow path member 26 and bonds the stacked bodies 14a together. This adhesive layer 30 also acts as a wall portion constituting the flow path, in which the flow path of the acidic gas Gc in the permeating gas flow path member 26 is formed in an envelope shape opened on the central tube 12 side.

As described above, the separation module 10 in the illustrated example is formed by stacking a plurality of the laminates 14 a and winding the laminate of the laminates 14 a around the central cylinder 12. 14
In the following description, for convenience, the direction corresponding to the winding of the laminate 14a indicated by the arrow y in the drawing is the winding direction, and the direction orthogonal to the winding direction indicated by the arrow x in the drawing is the width direction. And

In the separation module 10, the laminate 14a constituting the laminate wound product 14 may be one. However, by laminating and winding a plurality of laminated bodies 14a, the membrane area of the acidic gas separation membrane 20 can be increased, and the amount of acidic gas Gc separated by one separation module can be improved.
The number of stacked layers 14a may be appropriately set according to the processing speed and processing amount required for the separation module 10, the size of the separation module 10, and the like. Here, the number of laminated bodies 14a to be laminated is preferably 50 or less, more preferably 45 or less, and particularly preferably 40 or less. By setting the number of laminated bodies 14a to be this number, winding of the laminated body 14a around the central cylinder 12 becomes easy, and the workability can be improved.

In FIG. 2, the fragmentary sectional view of the laminated body 14a is shown. As described above, the arrow x is the width direction, and the arrow y is the winding direction.
In the illustrated example, as shown in FIG. 5 to be described later, the laminated body 14a includes a supply gas flow path member 24 sandwiched between two folded acid gas separation membranes 20 to form a sandwiching body 36. In addition, the permeate gas flow path member 26 is laminated. This configuration will be described in detail later.

As described above, in the separation module 10, the raw material gas G is supplied from one end face of the stacked body roll 14 through the opening 16 d of the telescope prevention plate 16. That is, the source gas G is supplied to the end portion (end surface) in the width direction (arrow x direction) of each stacked body 14a.
As conceptually shown in FIG. 2, the source gas G supplied to the end face in the width direction of the stacked body 14 a flows in the width direction through the supply gas flow path member 24. In this flow, the acidic gas Gc in contact with the acidic gas separation membrane 20 (facilitated transport membrane 20a) is separated from the source gas G by the carrier of the facilitated transport membrane 20a and transported in the stacking direction, and the acidic gas separation membrane. 20 passes in the stacking direction of the stacked body 14 a and flows into the permeating gas flow path member 26.
The acidic gas Gc that has flowed into the permeate gas flow path member 26 flows in the permeate gas flow path member 26 in the winding direction (the direction of the arrow y), reaches the central cylinder 12, and is centered from the through hole 12 a of the central cylinder 12. It flows into the cylinder 12. The acidic gas Gc that has flowed into the center tube 12 flows through the center tube 12 in the width direction and is discharged from the open end 12b.
Further, the residual gas Gr from which the acidic gas Gc has been removed flows in the width direction of the supply gas flow path member 24 and is discharged from the opposite end face of the laminate wound body 14. It is discharged to the outside of the separation module 10 through the part 16d.

The supply gas flow path member 24 is supplied with the source gas G from the end in the width direction, and brings the source gas G flowing in the member into contact with the acidic gas separation membrane 20.
Such a supply gas flow path member 24 functions as a spacer of the acid gas separation membrane 20 folded in half as described above, and constitutes a flow path for the source gas G. Further, the supply gas flow path member 24 preferably makes the source gas G turbulent. Considering this point, the supply gas flow path member 24 is preferably a member having a net shape (mesh shape / mesh structure), a woven fabric shape, a nonwoven fabric shape, a porous shape, or the like.

Various materials can be used as the material for forming the supply gas flow path member 24 as long as it has sufficient heat resistance and moisture resistance.
Examples include paper materials such as paper, fine paper, coated paper, cast coated paper, and synthetic paper, resin materials such as cellulose, polyester, polyolefin, polyamide, polyimide, polysulfone, aramid, and polycarbonate, and inorganic materials such as metal, glass, and ceramics. A material etc. are illustrated suitably.
Specific examples of the resin material include polyethylene, polystyrene (PS), polyethylene terephthalate, polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyphenylene sulfide (PPS), polysulfone (PSF), and polypropylene (PP). , Polyimide, polyetherimide, polyetheretherketone, polyvinylidene fluoride and the like are preferably exemplified. A plurality of materials may be used in combination as the material for forming such a supply gas flow path member 24.

The thickness of the supply gas flow path member 24 may be appropriately determined according to the supply amount of the source gas G, the required processing capacity, and the like.
Specifically, 100 to 1000 μm is preferable, 150 to 950 μm is more preferable, and 200 to 900 μm is particularly preferable.

In the separation module 10 of the present invention, the acidic gas separation membrane 20 has a facilitated transport membrane 20a and a porous support 20b that supports the facilitated transport membrane 20a. In the separation module 10 of the present invention, the acidic gas separation membrane 20 has a carrier diffusion suppression layer 20c between the facilitated transport membrane 20a and the porous support 20b.

The facilitated transport film 20a contains at least a carrier that reacts with the acidic gas Gc contained in the source gas G flowing through the supply gas flow path member 24, and a hydrophilic compound that supports the carrier. Such a facilitated transport film 20a has a function of selectively allowing the acidic gas Gc to permeate from the source gas G.
The porous support 20b substantially supports the facilitated transport film 20a.
The carrier diffusion suppressing layer 20c is a layer for preventing the carrier of the facilitated transport film 20a from being removed from the facilitated transport film 20a and further from the porous support 20b.
The acidic gas separation membrane 20 including the facilitated transport membrane 20a, the porous support 20b, and the carrier diffusion suppression layer 20c will be described in detail later.

The permeating gas channel member 26 is a member for allowing the acidic gas Gc that has reacted with the carrier and permeated through the acidic gas separation membrane 20 to flow through the through hole 12a of the central cylinder 12.
As described above, the laminated body 14a has the sandwiching body 36 in which the acidic gas separation membrane 20 is folded in half with the facilitated transport membrane 20a inside, and the supply gas flow path member 24 is sandwiched (see FIG. 5). By laminating the permeating gas flow path member 26 on the sandwiching body 36 and adhering with the adhesive layer 30 (adhesive 30a), one laminated body 14a is formed (see FIG. 7).
The permeating gas flow path member 26 functions as a spacer between the acidic gas separation membranes 20 and from the source gas G that reaches the through hole 12a of the central cylinder 12 toward the winding center (inner side) of the stacked body 14a. A flow path of the separated acid gas Gc is formed. Further, in order to properly form the flow path of the acidic gas Gc, the adhesive layer 30 described later needs to penetrate. In consideration of this point, the permeating gas channel member 26 is preferably a net-like (mesh / net-like), woven fabric, non-woven fabric, porous material or the like, similar to the supply gas channel member 24. .

In the present invention, the laminated body 14a is not limited to the configuration using the sandwiching body 36 in which the supply gas flow path member 24 is sandwiched between the folded acidic gas separation membrane 20. For example, the laminated body may be configured in the same manner as the sandwiching body 36 by using the supply gas flow path member 24 attached to the surface of the acidic gas separation membrane 20.

Various materials can be used as the material for forming the permeating gas channel member 26 as long as it has sufficient strength and heat resistance. Specifically, polyester-based materials such as epoxy-impregnated polyester, polyolefin-based materials such as polypropylene, fluorine-based materials such as polytetrafluoroethylene, inorganic materials such as metal, glass, and ceramics are preferably exemplified. . A plurality of materials may be used in combination as the material for forming such a permeating gas channel member 26. Further, a plurality of the same materials may be used.

The thickness of the permeating gas channel member 26 may be appropriately determined according to the supply amount of the source gas G, the required processing capacity, and the like.
Specifically, 100 to 1000 μm is preferable, 150 to 950 μm is more preferable, and 200 to 900 μm is particularly preferable.

As described above, the permeating gas channel member 26 is a channel for the acidic gas Gc that is separated from the source gas G and permeates the acidic gas separation membrane 20.
Therefore, it is preferable that the permeating gas channel member 26 has a low resistance to the flowing gas. Specifically, it is preferable that the porosity is high, the deformation is small when pressure is applied, and the pressure loss is small.

The porosity of the permeating gas channel member 26 is preferably 30 to 99%, more preferably 35 to 97.5%, and particularly preferably 40 to 95%.
Deformation when pressure is applied can be approximated by elongation when a tensile test is performed. The permeating gas channel member 26 preferably has an elongation of 5% or less and more preferably 4% or less when a load of 10 N / 10 mm width is applied.
The pressure loss can be approximated by a flow rate loss of compressed air that flows at a constant flow rate. The permeate gas channel member 26 has a flow rate loss of 7.5 L / min or less when air of 15 L (liter) / min is passed through the 15 cm square permeate gas channel member 26 at room temperature. Preferably, it is within 7 L / min.

The laminated body 14a is formed by laminating a supply gas flow path member 24, an acidic gas separation membrane 20, and a permeate gas flow path member 26.
As described above, the acidic gas separation membrane 20 includes the facilitated transport membrane 20a, the porous support 20b that substantially supports the facilitated transport membrane 20a, and the carrier diffusion suppression layer 20c.
Here, in the separation module 10 of the present invention, the carrier diffusion suppression layer 20c contains a fluorine-modified silicone compound, and the amount of fluorine atoms relative to silicon atoms in the carrier diffusion suppression layer 20c is 5 to 40 in atomic ratio. %. This will be described in detail later.

Hereinafter, the acidic gas separation membrane 20 in the separation module 10 of the present invention will be described in detail with reference to a schematic sectional view in the thickness direction of the acidic gas separation membrane 20 in FIG.

As described above, the facilitated transport film 20a has a function of selectively allowing the acidic gas Gc to permeate from the source gas G. In other words, the facilitated transport film 20a has a function of selectively transporting the acidic gas Gc.
Such a facilitated transport film 20a contains at least a hydrophilic compound such as a hydrophilic polymer, a carrier that reacts with an acidic gas, water, and the like.

The hydrophilic compound functions as a binder, retains moisture in the facilitated transport film 20a, and exhibits a function of separating an acidic gas such as carbon dioxide by a carrier. Moreover, it is preferable that a hydrophilic compound has a crosslinked structure from a heat resistant viewpoint.

From the viewpoint that the hydrophilic compound can be dissolved in water to form a coating composition, and the facilitated transport film 20a preferably has high hydrophilicity (moisturizing property), those having high hydrophilicity are preferable.
Specifically, the hydrophilic compound preferably has a hydrophilicity of 0.5 g / g or more in physiological saline, and has a hydrophilicity of 1 g / g or more in physiological saline. More preferably, the physiological saline has a hydrophilicity of 5 g / g or more, more preferably, the physiological saline has a hydrophilicity of 10 g / g or more, and the physiological saline has a hydrophilicity. Most preferably, the amount has a hydrophilicity of 20 g / g or more.

What is necessary is just to select the weight average molecular weight of a hydrophilic compound suitably in the range which can form a stable film | membrane. Specifically, 20,000 to 2,000,000 is preferable, 25,000 to 2,000,000 is more preferable, and 30,000 to 2,000,000 is particularly preferable.
By setting the weight average molecular weight of the hydrophilic compound to 20,000 or more, the facilitated transport film 20a having a stable and sufficient film strength can be obtained.
When the hydrophilic compound has a hydroxy group (—OH) as a crosslinkable group, the hydrophilic compound preferably has a weight average molecular weight of 30,000 or more. In this case, the weight average molecular weight is more preferably 40,000 or more, and more preferably 50,000 or more. When the hydrophilic compound has a hydroxy group as a crosslinkable group, the weight average molecular weight is preferably 6,000,000 or less from the viewpoint of production suitability.
In the case of having an amino group (—NH ₂ ) as a crosslinkable group, the hydrophilic compound preferably has a weight average molecular weight of 10,000 or more. In this case, the weight average molecular weight of the hydrophilic compound is more preferably 15,000 or more, and particularly preferably 20,000 or more. When the hydrophilic compound has an amino group as a crosslinkable group, the weight average molecular weight is preferably 1,000,000 or less from the viewpoint of production suitability.
In the present invention, the weight average molecular weight of various polymer materials may be measured as a molecular weight in terms of polystyrene (PS) by gel permeation chromatography (GPC). More specifically, in this specification, the weight average molecular weight (Mw) can be determined by using HLC-8220 (manufactured by Tosoh Corporation). The combination of the column and the eluent can be appropriately selected depending on the polymer material. If soluble in a polar organic solvent, use TSKgel Super AWM-H (Tosoh Corp., 6.0 mm ID × 15.0 cm) as the column and 10 mmol / L lithium bromide DMF (dimethylformamide) solution as the eluent. Can be sought. If the weight-average molecular weight of a silicone-based material such as a fluorine-modified silicone compound described later is used, TSKgel SuperHM-L (made by Tosoh Corp., 6.0 mm ID × 15.0 cm) is used as a column, and toluene is used as an eluent. Can be obtained.
Moreover, a commercial item can also be used for the hydrophilic compound, and when using a commercial item, the molecular weight nominally given in a catalog or a specification may be used. In this regard, the same applies to other polymer materials.

As the crosslinkable group forming the hydrophilic compound, those capable of forming a hydrolysis-resistant crosslink structure are preferably selected.
Specific examples include a hydroxy group, an amino group, a chlorine atom, a cyano group, a carboxy group, and an epoxy group. Among these, an amino group and a hydroxy group are preferably exemplified. Furthermore, most preferably, a hydroxy group is illustrated from the viewpoint of affinity with a carrier and a carrier carrying effect.

Specific examples of the hydrophilic compound include those having a single crosslinkable group, such as polyallylamine, polyacrylic acid, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, polyethyleneimine, polyvinylamine, polyornithine, polylysine, Examples include polyethylene oxide, water-soluble cellulose, starch, alginic acid, chitin, polysulfonic acid, polyhydroxymethacrylate, poly-N-vinylacetamide and the like. Most preferred is polyvinyl alcohol. Moreover, as a hydrophilic compound, these copolymers are also illustrated.

Examples of the hydrophilic compound having a plurality of crosslinkable groups include polyvinyl alcohol-polyacrylic acid copolymers. A polyvinyl alcohol-polyacrylic salt copolymer is preferable because of its high water absorption ability and high hydrogel strength even at high water absorption.
The content of polyacrylic acid in the polyvinyl alcohol-polyacrylic acid copolymer is, for example, 1 to 95 mol%, preferably 2 to 70 mol%, more preferably 3 to 60 mol%, particularly preferably 5 to 50 mol%. It is. The content of acrylic acid can be controlled by a known synthesis method.
In the polyvinyl alcohol-polyacrylic acid copolymer, the polyacrylic acid may be a salt. Examples of the polyacrylic acid salt in this case include ammonium salts and organic ammonium salts in addition to alkali metal salts such as sodium salts and potassium salts.

Polyvinyl alcohol is also available as a commercial product. Specific examples include PVA117 (manufactured by Kuraray Co., Ltd.), Poval (manufactured by Kuraray Co., Ltd.), polyvinyl alcohol (manufactured by Aldrich Co., Ltd.), J-Poval (manufactured by Nippon Vinegarten Poval Co., Ltd.) and the like. Various grades of molecular weight exist, but those having a weight average molecular weight of 130,000 to 300,000 are preferred.
A polyvinyl alcohol-polyacrylate copolymer (sodium salt) is also available as a commercial product. For example, Crustomer AP20 (made by Kuraray Co., Ltd.) is exemplified.

In the production method of the present invention, two or more hydrophilic compounds of the facilitated transport film 20a may be mixed and used.

In the formed facilitated transport film 20a, the content of the hydrophilic compound is appropriately determined depending on the type of the hydrophilic composition, the carrier, and the like so that the hydrophilic compound functions as a binder and can sufficiently retain moisture. , You can set.
Specifically, the content of the hydrophilic compound in the facilitated transport film 20a is preferably 0.5 to 50% by mass, more preferably 0.75 to 30% by mass, and particularly preferably 1 to 15% by mass. By setting the content of the hydrophilic compound within this range, the above-described function as a binder and moisture retention function can be stably and suitably expressed.

The crosslinked structure of the hydrophilic compound can be formed by a known method such as thermal crosslinking, ultraviolet crosslinking, electron beam crosslinking, radiation crosslinking, or photocrosslinking.
Photocrosslinking or thermal crosslinking is preferred, and thermal crosslinking is most preferred.

For the formation of the facilitated transport film 20a, it is preferable to use a crosslinking agent together with the hydrophilic composition. That is, the coating composition for forming the facilitated transport film 20a preferably contains a crosslinking agent.
As the crosslinking agent, one containing a crosslinking agent that reacts with a hydrophilic compound and has two or more functional groups capable of crosslinking such as thermal crosslinking or photocrosslinking is selected. The formed crosslinked structure is preferably a hydrolysis-resistant crosslinked structure.
From such a viewpoint, as a crosslinking agent added to the coating composition, an epoxy crosslinking agent, a polyvalent glycidyl ether, a polyhydric alcohol, a polyvalent isocyanate, a polyvalent aziridine, a haloepoxy compound, a polyvalent aldehyde, a polyvalent amine, An organic metal type crosslinking agent etc. are illustrated suitably. More preferred are polyvalent aldehydes, organometallic crosslinking agents and epoxy crosslinking agents, and among them, polyvalent aldehydes such as glutaraldehyde and formaldehyde having two or more aldehyde groups are preferred.

The epoxy crosslinking agent is a compound having 2 or more epoxy groups, and a compound having 4 or more is also preferable. Epoxy crosslinking agents are also commercially available, for example, trimethylolpropane triglycidyl ether (manufactured by Kyoeisha Chemical Co., Epolite 100MF, etc.), Nagase ChemteX Corporation EX-411, EX-313, EX-614B, EX -810, EX-811, EX-821, EX-830, Epiol E400 manufactured by NOF Corporation, and the like.
As a compound similar to an epoxy crosslinking agent, an oxetane compound having a cyclic ether is also preferably used. The oxetane compound is preferably a polyvalent glycidyl ether having two or more functional groups. Examples of commercially available products include EX-411, EX-313, EX-614B, EX-810, EX-811, EX manufactured by Nagase ChemteX Corporation. -821, EX-830, etc.

Examples of the polyvalent glycidyl ether include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, pentaerythritol polyglycidyl ether, propylene Examples include glycol glycidyl ether and polypropylene glycol diglycidyl ether.

Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, glycerin, polyglycerin, propylene glycol, diethanolamine, triethanolamine, polyoxypropyl, oxyethyleneoxypropylene block copolymer , Pentaerythritol, sorbitol and the like.

Examples of the polyvalent isocyanate include 2,4-tolylene diisocyanate and hexamethylene diisocyanate.
Examples of the polyvalent aziridine include 2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], 1,6-hexamethylenediethyleneurea, diphenylmethane-bis-4,4′-N, N Examples include '-diethylene urea.

Examples of the haloepoxy compound include epichlorohydrin and α-methylchlorohydrin.
Examples of the polyvalent aldehyde include glutaraldehyde and glyoxal.
Examples of the polyvalent amine include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, and polyethyleneimine.
Furthermore, examples of the organometallic crosslinking agent include organic titanium crosslinking agents and organic zirconia crosslinking agents.

For example, when polyvinyl alcohol having a weight average molecular weight of 130,000 or more is used as the hydrophilic compound, it is possible to form a crosslinked structure having good reactivity with this hydrophilic compound and excellent hydrolysis resistance. Therefore, an epoxy crosslinking agent or glutaraldehyde is preferably used as the crosslinking agent.
When a polyvinyl alcohol-polyacrylic acid copolymer is used as the hydrophilic compound, an epoxy crosslinking agent or glutaraldehyde is preferably used as the crosslinking agent.
When a polyallylamine having a weight average molecular weight of 10,000 or more is used as the hydrophilic compound, it is possible to form a crosslinked structure having good reactivity with this hydrophilic compound and excellent hydrolysis resistance. As the crosslinking agent, an epoxy crosslinking agent, glutaraldehyde, and an organometallic crosslinking agent are preferably used.
When polyethyleneimine or polyallylamine is used as the hydrophilic compound, an epoxy crosslinking agent is preferably used as the crosslinking agent.

What is necessary is just to set the quantity of a crosslinking agent suitably according to the kind of hydrophilic compound and crosslinking agent.
Specifically, the amount is preferably 0.001 to 80 parts by weight, more preferably 0.01 to 60 parts by weight, and particularly preferably 0.1 to 50 parts by weight with respect to 100 parts by weight of the crosslinkable group possessed by the hydrophilic compound. preferable. By setting the content of the cross-linking agent in the above range, a facilitated transport film having good cross-linking structure formation and excellent shape maintainability can be obtained.
Focusing on the crosslinkable group possessed by the hydrophilic compound, the crosslinked structure is preferably formed by reacting 0.001 to 80 mol of a crosslinking agent with respect to 100 mol of the crosslinkable group possessed by the hydrophilic compound.

In the facilitated transport film 20a, the carrier (acid gas carrier) reacts with an acid gas (for example, carbon dioxide gas (CO ₂ )) to transport the acid gas.

The carrier is a water-soluble compound having affinity with acidic gas and showing basicity. Specific examples include alkali metal compounds, nitrogen-containing compounds, and sulfur oxides.
The carrier may react indirectly with the acid gas, or the carrier itself may react directly with the acid gas.
Examples of the former include those that react with other gases contained in the supply gas, show basicity, and the basic compound reacts with the acidic gas. More specifically, OH react with steam (water) ^- was released, the OH ^- that reacts with CO _2, a compound can be incorporated selectively CO ₂ in facilitated transport membrane 20a For example, an alkali metal compound.
The latter is such that the carrier itself is basic, for example, a nitrogen-containing compound or a sulfur oxide.

Examples of the alkali metal compound include alkali metal carbonate, alkali metal bicarbonate, and alkali metal hydroxide. Here, as the alkali metal, an alkali metal element selected from cesium, rubidium, potassium, lithium, and sodium is preferably used. In addition, in this invention, an alkali metal compound contains the salt and its ion other than alkali metal itself.

Examples of the alkali metal carbonate include lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, and cesium carbonate.
Examples of the alkali metal bicarbonate include lithium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, rubidium hydrogen carbonate, and cesium hydrogen carbonate.
Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide.
Among these, an alkali metal carbonate is preferable, and a compound containing potassium, rubidium, and cesium having high solubility in water is preferable from the viewpoint of good affinity with acidic gas.

When using an alkali metal compound as a carrier, two or more kinds of carriers may be used in combination.
When two or more types of carriers are present in the facilitated transport film 20a, different carriers can be separated from each other in the film. Thereby, due to the difference in deliquescence of a plurality of carriers, due to the water absorption of the facilitated transport film 20a, the facilitated transport films 20a or the facilitated transport film 20a and other members are adhered to each other during production. (Blocking) can be suitably suppressed.
In the case where two or more alkali metal compounds are used as a carrier in terms of more suitably obtaining a blocking inhibitory effect, the first compound having deliquescence and the specific gravity having lower deliquescence than the first compound It is preferable to contain the 2nd compound with small. As an example, the first compound is exemplified by cesium carbonate, and the second compound is exemplified by potassium carbonate.

Nitrogen-containing compounds include amino acids such as glycine, alanine, serine, proline, histidine, taurine, diaminopropionic acid, hetero compounds such as pyridine, histidine, piperazine, imidazole, triazine, monoethanolamine, diethanolamine, triethanolamine , Alkanolamines such as monopropanolamine, dipropanolamine and tripropanolamine, cyclic polyetheramines such as cryptand [2.1] and cryptand [2.2], cryptand [2.2.1] and cryptand [ And bicyclic polyetheramines such as 2.2.2], porphyrin, phthalocyanine, ethylenediaminetetraacetic acid and the like.
Examples of sulfur compounds include amino acids such as cystine and cysteine, polythiophene, dodecyl thiol and the like.

What is necessary is just to set suitably content of the carrier in the facilitated-transport film | membrane 20a according to the kind etc. of a carrier or a hydrophilic compound. Specifically, the amount of carriers in the facilitated transport film 20a is preferably 0.3 to 30% by mass, more preferably 0.5 to 25% by mass, and 1 to 20% by mass. Is particularly preferred.
By setting the content of the carrier in the coating composition in the above range, salting out before coating can be suitably prevented, and the facilitated transport film 20a formed can reliably exhibit the function of separating acidic gas. .
The weight ratio of the hydrophilic compound to the carrier in the coating composition is preferably 1: 9 to 2: 3, more preferably 1: 4 to 2: 3, and more preferably 3: 7 to 2 in terms of the weight ratio of the hydrophilic compound to the carrier. : 3 is particularly preferable.

The facilitated transport film 20a may contain a thickener as necessary. That is, the coating composition for forming the facilitated-transport film | membrane 20a may contain a thickener as needed.
As the thickener, for example, thickening polysaccharides such as agar, carboxymethylcellulose, carrageenan, chitansan gum, guar gum and pectin are preferable. Among these, carboxymethylcellulose is preferable from the viewpoints of film forming property, availability, and cost.
By using carboxymethyl cellulose, a coating composition having a desired viscosity can be easily obtained with a small amount of content, and at least a part of components other than the solvent contained in the coating composition cannot be dissolved in the coating composition. There is little risk of precipitation.

The content of the thickener is preferably as small as possible as long as it can be adjusted to the target viscosity.
As a general index, 10% by mass or less is preferable, 0.1 to 5% by mass is more preferable, and 0.1 to 2% by mass or less is more preferable.

The facilitated transport film 20a (coating composition for forming the facilitated transport film 20a) contains various components as necessary in addition to such a hydrophilic compound, a crosslinking agent and a carrier, or a thickener. May be.

Examples of such components include antioxidants such as dibutylhydroxytoluene (BHT), compounds having 3 to 20 carbon atoms or fluorinated alkyl groups having 3 to 20 carbon atoms and hydrophilic groups, and siloxane structures. Specific compounds such as compounds having a surfactant, surfactants such as sodium octoate and sodium 1-hexasulfonate, polymer particles such as polyolefin particles and polymethyl methacrylate particles, and the like.
In addition, a catalyst, a humectant, a hygroscopic agent, an auxiliary solvent, a film strength modifier, a defect detector, and the like may be used as necessary.

Further, in the separation module of the present invention, the thickness of the facilitated transport membrane 20a may be set as appropriate so that the desired performance can be obtained according to the composition of the facilitated transport membrane 20a. Specifically, it is preferably 3 to 1000 μm, more preferably 5 to 500 μm, and particularly preferably 5 to 100 μm.
By making the film thickness of the facilitated-transport film | membrane 20a into the said range, it is preferable at points, such as being able to improve gas-permeation performance and suppressing generation | occurrence | production of a defect. The film thickness of the facilitated transport film 20a can be measured by cross-sectional observation using a scanning electron microscope or the like.

The porous support 20b supports the facilitated transport film 20a and the carrier diffusion suppression layer 20c, and has a permeability to an acidic gas such as carbon dioxide. In the following description, the porous support 20b is also referred to as the support 20b.
As the support 20b, various known materials can be used as long as they have this function.

In the production method of the present invention, the support 20b may be a single layer. However, the support 20b preferably has a two-layer structure in which a porous film and an auxiliary support film are stacked. By having such a two-layer configuration, the above-described acidic gas permeability and the function of supporting the facilitated transport film 20a are more reliably expressed.
In the two-layer support 20b, the porous membrane is on the facilitated transport membrane 20a side.
When the porous support is a single layer, various materials exemplified below as the porous film and the auxiliary support film can be used as the forming material.

The porous membrane is preferably made of a material having heat resistance and low hydrolyzability. Specific examples of such a porous membrane include membrane filter membranes such as polysulfone (PSF), polyethersulfone, polypropylene (PP) and cellulose, interfacially polymerized thin films of polyamide and polyimide, polytetrafluoroethylene (PTFE). And a stretched porous membrane of high molecular weight polyethylene.
Among them, a porous film containing one or more materials selected from fluorine-containing polymers such as PTFE, PP and PSF is preferably exemplified. Among them, a stretched porous membrane of PTFE or high molecular weight polyethylene has a high porosity, has little inhibition of diffusion of acidic gas (especially carbon dioxide gas), and is preferable from the viewpoints of strength and suitability for production. In particular, a stretched porous membrane of PTFE is preferably used in terms of heat resistance and low hydrolyzability.

As the porous film, in addition to such an organic material, an inorganic material or an organic-inorganic hybrid material may be used.
Examples of the inorganic porous support include a porous substrate mainly composed of ceramics. By using ceramics as a main component, it is excellent in heat resistance, corrosion resistance, etc., and mechanical strength can be increased. There are no particular limitations on the type of ceramic, and various commonly used ceramics can be used. Examples of the ceramic include alumina, silica, silica-alumina, mullite, cordierite, zirconia and the like.
Further, a combination of two or more kinds of ceramics, a composite of ceramic and metal, or a composite of ceramic and organic compound may be used.

In the support 20b, the auxiliary support membrane is provided for reinforcing the porous membrane.
As the auxiliary support membrane, various materials can be used as long as they satisfy the required strength, stretch resistance and gas permeability. For example, a nonwoven fabric, a woven fabric, a net, and a mesh can be appropriately selected and used.

The auxiliary support membrane is also preferably made of a material having heat resistance and low hydrolyzability, like the porous membrane described above.
Considering this point, the fibers constituting the nonwoven fabric, woven fabric, and knitted fabric are excellent in durability and heat resistance, polyolefin such as PP, modified polyamide such as aramid (trade name), PTFE, polyvinylidene fluoride, etc. A fiber made of a fluorine-containing resin is preferable. It is preferable to use the same material as the resin material constituting the mesh. Among these materials, a non-woven fabric made of PP that is inexpensive and has high mechanical strength is particularly preferably exemplified.

When the support 20b has an auxiliary support film, the mechanical strength can be improved. Therefore, as will be described later, even when the acid gas separation membrane 20 is formed using so-called RtoR (roll-to-roll), it is possible to prevent wrinkles from being generated on the support 20b, and to improve productivity. Can also be increased.

If the support 20b is too thin, the strength is difficult. Considering this point, the thickness of the porous membrane is preferably 5 to 100 μm, and the thickness of the auxiliary support membrane is preferably 50 to 300 μm.
When the support 20b is a single layer, the thickness of the support 20b is preferably 30 to 500 μm.

When the support 20b has a two-layer structure including a porous membrane and an auxiliary support membrane, the porous membrane preferably has a maximum pore diameter of 1 μm or less. In addition, what is necessary is just to measure the largest hole diameter of a porous membrane with a palm porometer, for example.
Further, the average pore diameter of the pores of the porous membrane is preferably 0.001 to 10 μm, more preferably 0.002 to 5 μm, and particularly preferably 0.005 to 1 μm. By setting the average pore diameter of the porous membrane within this range, it is possible to suitably prevent the adhesive application region described later from sufficiently impregnating the adhesive and preventing the porous membrane from passing the acidic gas. .

As shown in FIG. 3, in the separation module 10, the acidic gas separation membrane 20 is formed with a carrier diffusion suppression layer 20c between the facilitated transport membrane 20a and the support 20b.
The carrier diffusion suppressing layer 20c prevents carriers from escaping from the facilitated transport film 20a and further diffusing through the support 20b. The carrier diffusion suppression layer 20c also has an effect of supporting the facilitated transport film 20a together with the support 20b and preventing the facilitated transport film 20a from penetrating into the support 20b due to pressure.

Here, in the separation module 10 of the present invention, the carrier diffusion suppression layer 20c of the acidic gas separation membrane 20 contains a fluorine-modified silicone compound, and the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer 20c is The atomic ratio is 5 to 40%.
By having such a configuration, the separation module 10 of the present invention prevents the carrier from coming off from the facilitated transport film 20a, and the separation module 10 having excellent durability can be obtained.

As shown in Patent Document 2 and Patent Document 3, in the acidic gas separation module using the facilitated transport membrane, in order to prevent the carriers that have escaped from the facilitated transport membrane from exiting the porous support, A carrier diffusion suppression layer (intermediate layer) is provided on the surface of the porous support, and a facilitated transport film is formed thereon. Examples of the material for forming the carrier diffusion suppression layer include siloxane, silicone rubber, organopolysiloxane, and the like. By having such a carrier diffusion suppression layer, it is possible to suppress the carriers from coming out of the facilitated transport film 20a and further from the support 20b.

However, as described above, during the acidic gas separation operation, the source gas G having a temperature of 100 to 130 ° C. and a humidity of about 90% is supplied at a pressure of about 1.5 MPa. Therefore, even if the carrier diffusion suppression layer is formed, the carriers gradually escape from the facilitated transport film and pass through the carrier diffusion suppression layer and the support. In particular, when an alkali metal compound is used as a carrier, the carrier is easily diffused.
In recent years, the acid gas separation module has been required to have higher durability.
Therefore, in the conventional acidic gas separation module using siloxane, silicone rubber, organopolysiloxane, etc. as the carrier diffusion suppression layer, it cannot be said that suppression of carrier escape is sufficiently performed, and durability is sufficient. I can't say that.

In contrast, in the separation module 10 of the present invention, the carrier diffusion suppression layer 20c of the acidic gas separation membrane 20 contains a fluorine-modified silicone compound, and the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer 20c is The atomic ratio is 5 to 40%. That is, in the separation module 10 of the present invention, the atomic ratio of “(number of fluorine atoms / number of silicon atoms) × 100” in the carrier diffusion suppression layer 20c is 5 to 40%.
In the present invention having such a configuration, the carrier diffusion suppressing layer 20c has appropriate hydrophobicity, and fluorine atoms imparting hydrophobicity are appropriately dispersed. As a result, according to the present invention, since the penetration of carriers can be suppressed by having hydrophobicity, it is possible to suppress the escape of carriers from the facilitated transport film 20a. In addition, according to the present invention, even if carriers escape from the facilitated transport film 20a, it is possible to prevent the carriers from exiting the carrier diffusion suppression layer 20c. In particular, when an alkali metal compound is used as the carrier, the penetration of the carrier can be suitably suppressed by imparting hydrophobicity, and the carrier can be prevented from coming off.
Therefore, according to the present invention, it is possible to obtain the separation module 10 with excellent durability, in which carrier escape from the facilitated transport film 20a is suitably prevented.

In the separation module 10 of the present invention, when the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer 20c is less than 5% in terms of atomic ratio, the effect of imparting hydrophobicity is weak and carrier escape cannot be sufficiently suppressed. Produce.
Further, when the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppressing layer 20c exceeds 40% in terms of atomic ratio, the gas permeability of the carrier diffusion suppressing layer 20c is deteriorated, the hydrophobicity is too high, and the hydrophilic facilitated transport. There arises a problem that the film 20a cannot be formed properly.
In consideration of the above points, the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer 20c is preferably 10 to 20% in terms of atomic ratio.

The ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer 20c may be detected by a known method such as fluorescent X-ray elemental analysis (XRF) or X-ray electron spectroscopy (XPS). This also applies to the fluorine-modified silicone compound.

Further, in the fluorine-modified silicone compound contained in the carrier diffusion suppression layer 20c, the ratio of fluorine atoms to silicon atoms is preferably 20 to 300%, more preferably 100 to 200%.
By setting the ratio of fluorine atoms to silicon atoms in the fluorine-modified silicone compound to 20% or more, it is preferable in that the effect of imparting hydrophobicity can be sufficiently obtained and the escape of carriers can be sufficiently suppressed.
In addition, by setting the ratio of fluorine atoms to silicon atoms in the fluorine-modified silicone compound to 300% or less, carrier diffusion suppressing layer 20c having good mechanical strength can be formed, and cracks and the like of carrier diffusion suppressing layer 20c can be formed. This is preferable in that it can prevent the carrier from coming off.

Furthermore, the weight average molecular weight of the fluorine-modified silicone compound contained in the carrier diffusion suppressing layer 20c is not particularly limited. Specifically, the weight average molecular weight of the fluorine-modified silicone compound contained in the carrier diffusion suppression layer 20c is often 100,000 or less from the viewpoint of handleability, but the weight average molecular weight is preferably 20000 or less, More preferably, it is 10,000 or less.
Setting the weight average molecular weight of the fluorine-modified silicone compound to 20000 or less is preferable in that the fluorine-modified silicone compound can be appropriately dispersed when the fluorine-modified silicone compound is dispersed in a polydimethylsiloxane polymer described later.

The fluorine-modified silicone compound contained in the carrier diffusion suppressing layer 20c may be non-crosslinkable or may have a crosslinked structure. In addition, when it has a crosslinked structure, you may synthesize | combine by bridge | crosslinking the fluorine-modified silicone compound which has a crosslinkable group. Alternatively, the carrier diffusion suppressing layer 20c may contain both a non-crosslinkable fluorine-modified silicone compound and a fluorine-modified silicone compound having a crosslinked structure, or may be composed of only one.

A specific embodiment of the fluorine-modified silicone compound is not particularly limited as long as it is a silicone (polysiloxane) into which a fluorine atom is introduced, but the fluorine-modified silicone compound having a repeating unit represented by the following general formula (1) Is mentioned.

In general formula (1), R ¹ and R ² each independently represents an alkyl group that may contain a fluorine atom, and at least ^one of R ¹ and R ² contains a fluorine atom.
The number of carbon atoms in the alkyl group is not particularly limited, but is often 1 to 10, preferably 1 to 5 and more preferably 1 to 3 from the viewpoint of handleability.
In addition, when a fluorine atom is introduced, it is introduced instead of a hydrogen atom in the alkyl group.
A preferred embodiment of the alkyl group containing a fluorine atom includes a group represented by —CH ₂ — (CF ₂ ) _n —CF ₃ . n represents an integer of 1 to 5.

In addition, in the said fluorine-modified silicone compound, repeating units other than the repeating unit represented by General formula (1) may be contained, for example, the repeating unit represented by General formula (2) is contained. It may be.

In general formula (2), R ³ and R ⁴ each independently represents an alkyl group.
The number of carbon atoms in the alkyl group is not particularly limited, but is often 1 to 10, preferably 1 to 5 and more preferably 1 to 3 from the viewpoint of handleability.

Various commercially available products can also be used for such fluorine-modified silicone compounds.
A plurality of fluorine-modified silicone compounds may be used in combination.

The carrier diffusion suppression layer 20c may contain various materials in addition to the fluorine-modified silicone compound. In particular, when the fluorine-modified silicone compound is non-crosslinkable, the fluorine-modified silicone compound is dispersed in a matrix (preferably a network structure) formed by a compound (particularly a polymer compound) such as polyorganosiloxane. It is preferable that the configuration is as follows. That is, the carrier diffusion suppression layer 20c may be configured to include a fluorine-modified silicone compound and a matrix resin. When the carrier diffusion suppression layer 20c includes a matrix resin, the matrix resin is preferably a matrix resin having a crosslinked structure.
As the matrix resin, an organopolysiloxane having a non-crosslinking property or a crosslinked structure is preferably mentioned as described later. In addition, in order to introduce | transduce a crosslinked structure into matrix resin, the method of using the organopolysiloxane which has a crosslinkable group is mentioned, for example. The group mentioned above is illustrated as a kind of crosslinkable group. Moreover, in the said method, you may use a crosslinking agent, a photo-acid generator, etc. together as needed. Moreover, the organopolysiloxane serving as the matrix resin is a compound different from the fluorine-modified silicone compound and usually does not contain fluorine atoms.
In addition, when the carrier diffusion suppression layer 20c contains a compound other than the fluorine-modified silicone compound, the amount of fluorine atoms relative to silicon atoms in the carrier diffusion suppression layer 20c is an atom in all the compounds contained in the carrier diffusion suppression layer 20c. The ratio should be 5 to 40%.

Specific examples of the compound other than the fluorine-modified silicone compound contained in the carrier diffusion suppressing layer 20c include compounds having a functional group that reacts with a hydroxyl group and / or a carboxyl group. More specifically, a compound having at least one of an epoxy group, an amino group, a methoxy group, an ethoxy group, a hydroxyl group, and a carboxyl group is exemplified.
In addition, the functional group that reacts with the hydroxyl group and / or the carboxyl group may react in the carrier diffusion suppression layer 20c to be converted into a crosslinked structure.

As such a compound, Preferably, the compound and silicone containing compound which have a silicone bond are illustrated. Specifically, silicone-containing polyacetylene such as organopolysiloxane (silicone resin) and polytrimethylsilylpropyne can be used. Specific examples of the organopolysiloxane include those represented by the following general formula.

In the above general formula, n represents an integer of 1 or more. Here, from the viewpoint of availability, volatility, viscosity, etc., the average value of n is preferably in the range of 10 to 1000000, and more preferably in the range of 100 to 100,000.
R _1n , R _2n , R ₃ and R ₄ are each selected from the group consisting of a hydrogen atom, alkyl group, vinyl group, aralkyl group, aryl group, hydroxyl group, amino group, carboxyl group and epoxy group. Indicates either. Note that n existing R _1n and R _2n may be the same or different. Further, the alkyl group, aralkyl group and aryl group may have a ring structure. Further, the alkyl group, vinyl group, aralkyl group and aryl group may have a substituent, and the substituent in this case is, for example, an alkyl group, vinyl group, aryl group, hydroxyl group, amino group, carboxyl group. , An epoxy group and a fluorine atom. These substituents may further have a substituent, if possible.
The alkyl group, vinyl group, aralkyl group and aryl group selected from R _1n , R _2n , R ₃ and R ₄ are alkyl groups having 1 to 20 carbon atoms, vinyl groups, More preferred are an aralkyl group having 7 to 20 carbon atoms and an aryl group having 6 to 20 carbon atoms.

R _1n , R _2n , R ₃ and R ₄ are preferably methyl groups or epoxy-substituted alkyl groups. For example, PDMS derivatives such as epoxy-modified polydimethylsiloxane (PDMS) can be suitably used.

Further, the carrier diffusion suppressing layer 20c may contain a polymer obtained by polymerizing the aforementioned various compounds such as the organopolysiloxane represented by the above general formula.
In particular, when the fluorine-modified silicone compound is non-crosslinkable, the fluorine-modified silicone compound is dispersed in a matrix structure (crosslinked structure) formed by a polymer of a compound such as organopolysiloxane. It is preferable that it is as described above.

In addition to the above-mentioned organopolysiloxane, the carrier diffusion suppression layer 20c includes a silicone material such as poly [1- (trimethylsilyl) -1-propyne] (PTMSP), a butadiene-based / isoprene-based rubber material, a low density Polymethylpentene or the like can also be used.

The thickness of the carrier diffusion suppressing layer 20c depends on the material for forming the carrier diffusion suppressing layer 20c, the assumed operating conditions of the separation module 10, the carriers and hydrophilic compounds contained in the facilitated transport film 20a, the physical properties of the facilitated transport film 20a, and the like. Accordingly, it may be set appropriately.
According to the study by the present inventors, the thickness of the carrier diffusion suppression layer 20c is preferably 0.5 to 10 μm, and more preferably 0.5 to 5 μm.
By setting the thickness of the carrier diffusion suppressing layer 20c to 0.5 μm or more, it is preferable in terms of being able to suitably prevent the carrier from being removed and the facilitated transport film 20a to be suitably supported.
By setting the thickness of the carrier diffusion suppression layer 20c to 10 μm or less, it is preferable in that the gas permeability can be prevented from being lowered and the acidic gas separation membrane 20 can be prevented from becoming unnecessarily thick.

In the acidic gas separation membrane 20 of the separation module 10 in the illustrated example, the carrier diffusion suppression layer 20c is formed on (on the surface of) the support 20b, but the present invention is not limited to this.
For example, a part of the carrier diffusion suppressing layer 20c may be in a state where it has entered (soaked) the inside of the support 20b, or all may be in a state where it has entered the inside of the support 20b.

In the separation module 10 of the present invention, the acidic gas separation membrane 20 preferably has a protective layer on the surface, that is, the facilitated transport membrane 20a.
As described above, when the separation module 10 winds the laminate 14a in which the sandwiched body 36 formed by the acidic gas separation membrane 20 and the supply gas flow path member 24 and the permeate gas flow path member 26 are wound, The facilitated transport film 20a may be damaged by the sliding contact between the facilitated transport film 20a and the supply gas flow path member 24.
On the other hand, by having a protective layer on the surface of the acidic gas separation membrane 20, the facilitated transport membrane 20a is prevented by the sliding contact between the facilitated transport membrane 20a and the supply gas flow path member 24, and more acidic. A separation module 10 having excellent gas separation performance can be obtained.

Various materials can be used as the material for forming the protective layer, and various compounds exemplified in the carrier diffusion suppression layer 20c described above are preferably used. In particular, like the carrier diffusion suppression layer 20c, the PDMS derivative is preferably exemplified.

What is necessary is just to set the thickness of a protective layer suitably according to the characteristic of the facilitated-transport film | membrane 20a, the characteristic of the member 24 for supply gas flow paths, etc. Specifically, it is preferably 0.1 to 500 μm, more preferably 0.5 to 100 μm.
Setting the thickness of the protective layer in the above range is preferable in that the facilitated transport film 20a can be suitably protected while suppressing a decrease in gas permeability due to the presence of the protective layer.

Such an acidic gas separation membrane 20 may be produced by various known methods. Preferably, it is produced by a coating method using RtoR.
As is well known, RtoR means that a substrate is delivered from a roll formed by winding a long substrate (object to be processed) and conveyed in the longitudinal direction, and the coating composition is applied and dried. It is a manufacturing method which winds up the board | substrate in roll shape.

When the acidic gas separation membrane 20 is produced, a roll formed by winding a long support 20b is loaded into a carrier diffusion suppression layer 20c forming apparatus, and the support is sent out from the roll. While transporting 20b in the longitudinal direction, a coating composition to be the carrier diffusion suppression layer 20c is applied.
Here, the conveyance speed of the support 20b is preferably faster from the viewpoint of productivity. However, in order to apply the coating composition uniformly, it is preferably 3 to 200 m / min, more preferably 5 to 150 m / min, and particularly preferably 10 to 120 m / min.

The coating composition that becomes the carrier diffusion suppressing layer 20c includes the monomer, dimer, trimer, oligomer, prepolymer, polymer, and the like of the aforementioned fluorine-modified silicone compound or the compound that becomes the carrier diffusion suppressing layer 20c such as organopolysiloxane. A resin layer (resin film) by a coating method in which a mixture of the above, a curing agent, a curing accelerator, a crosslinking agent, a thickener, a reinforcing agent, and a filler are dissolved and / or dispersed in an organic solvent. It is a general coating composition (coating liquid / paint) used when forming the like. Such a coating composition may be prepared by a known method.

Here, the viscosity of the coating composition to be the carrier diffusion suppression layer 20c is such that the carrier diffusion suppression layer 20c is formed on the support 20b such that a part of the coating composition enters the support 20b or a state in which all enters the support 20b. What is necessary is just to set suitably according to a position etc.
According to the study by the present inventors, the coating composition to be the carrier diffusion suppressing layer 20c preferably has a viscosity at 25 ° C. of 0.1 Pa · sec or more, more preferably 0.4 Pa · sec or more. Preferably, it is 0.5 Pa · sec.
The coating composition to be the carrier diffusion suppression layer 20c is preferable in that the appropriate carrier diffusion suppression layer 20c can be stably formed by setting the viscosity at 25 ° C. to 0.1 Pa · sec or more.
On the other hand, what is necessary is just to set the upper limit of the viscosity in 25 degreeC of the coating composition used as the carrier diffusion suppression layer 20c according to the limit viscosity in the coating device to be used. Specifically, the upper limit of the viscosity at 25 ° C. of the coating composition to be the carrier diffusion suppression layer 20c is such that the thickness of the carrier diffusion suppression layer 20c and the amount of penetration into the support 20b can be suitably controlled. In this respect, 1000 Pa · sec or less is preferable.

In the present invention, the viscosity of various coating compositions and the like may be measured at 25 ° C. according to JIS Z8803 at a rotation speed of 60 rpm using a B-type viscometer.

As the coating device for the coating composition to be the carrier diffusion suppression layer 20c, various known devices corresponding to the coating composition can be used.
Specifically, roll coater, direct gravure coater, offset gravure coater, 1 roll kiss coater, 3 reverse roll coater, forward rotation roll coater, curtain flow coater, extrusion die coater, air doctor coater, blade coater, rod coater And knife coaters, squeeze coaters, reverse roll coaters, bar coaters and the like.
Among these, in consideration of the control of the coating composition, the coating amount of the coating composition, the penetration amount of the coating composition, etc., a roll coater, a direct gravure coater, an offset gravure coater, a single roll kiss coater, a three reverse roll coater, A rotary roll coater, a squeeze coater, a reverse roll coater and the like are preferably exemplified.

Once the coating composition to be the carrier diffusion suppression layer 20c is applied, the coating composition is then dried to form the carrier diffusion suppression layer 20c. The drying may be performed by a known method such as hot air drying or drying with a heater.

In addition, after drying the coating composition used as the carrier diffusion suppression layer 20c as needed, the coating composition is further cured (crosslinked) to form the carrier diffusion suppression layer 20c.
For curing, a method capable of curing, such as heat curing, ultraviolet irradiation, electron beam irradiation, or the like, may be appropriately selected according to the material for forming the carrier diffusion suppression layer 20c. Here, for the reason that curling and deformation of the support 20b can be suppressed and deterioration of the resin constituting the support 20b can be prevented, curing of the coating composition by ultraviolet irradiation or short heating is preferably used. Is done. In particular, curing by ultraviolet irradiation is most preferably used. That is, in the present invention, it is preferable to form the carrier diffusion suppression layer 20c with a coating composition using a monomer or the like that can be cured by irradiation with ultraviolet rays.

Depending on the composition of the coating composition to be the carrier diffusion suppressing layer 20c, the coating composition may be dried and cured at the same time.
Moreover, you may perform drying and / or hardening of a coating composition in inert atmosphere, such as nitrogen atmosphere, as needed.

When the carrier diffusion suppression layer 20c is formed on the support 20b in this manner, the support 20b on which the carrier diffusion suppression layer 20c is formed is wound into a roll.
In the following description, the support 20b on which the carrier diffusion suppression layer 20c is formed is also referred to as a composite.

The protective layer formed on the facilitated transport film 20a can be basically formed in the same manner as the carrier diffusion suppression layer 20c.

Next, the roll of the composite (the support 20b on which the carrier diffusion suppressing layer 20c is formed) is loaded into the apparatus for forming the facilitated transport film 20a, and the composite is sent out from the roll and transported in the longitudinal direction while being facilitated transport. A coating composition to be the film 20a is applied.

What is necessary is just to set suitably the conveyance speed of the composite_body | complex at the time of forming the facilitated-transport film | membrane 20a according to a composition, a viscosity, etc. of a coating composition.
Here, when the conveyance speed of the composite is too fast, there is a fear that the coating film thickness uniformity of the coating composition is lowered and drying of the coating composition is insufficient, and when it is too slow, the productivity is lowered. Considering this point, the conveyance speed of the composite is preferably 0.5 m / min or more, more preferably 0.75 to 200 m / min, and particularly preferably 1 to 200 m / min.

As described above, the facilitated transport film 20a contains a hydrophilic compound such as a hydrophilic polymer, a carrier that reacts with an acidic gas, water, and the like.
Accordingly, the coating composition (coating liquid / paint) for forming such a facilitated transport film 20a includes the above-described hydrophilic compound, carrier and water, or further a necessary composition such as a crosslinking agent. It is a thing. The water may be room temperature water or warm water.
The hydrophilic compound may be crosslinked, partially crosslinked, or uncrosslinked, or a mixture of these. This coating composition may also be prepared by a known method.

The coating composition to be the facilitated transport film 20a preferably has a viscosity at 25 ° C. of 0.1 Pa · sec or more.
By setting the viscosity at 25 ° C. of the coating composition to 0.1 Pa · sec or more, it is preferable in terms of suppressing repelling when the coating composition is applied, improving the coating uniformity of the coating composition, and the like. .

Various known methods can be used to apply the coating composition to be the facilitated transport film 20a, and examples thereof include the same as the carrier diffusion suppression layer 20c described above. In consideration of the preferable viscosity of the coating composition to be the facilitated transport film 20a, the coating amount of the coating composition, and the like, a roll coater, a bar coater, a positive rotation roll coater, a knife coater, and the like are preferably used.

If the coating composition used as the facilitated-transport film | membrane 20a is apply | coated, then this applied composition is dried and the facilitated-transport film | membrane 20a is formed.
Various known methods for drying by removing water, such as warm air drying or drying by heating the support 20b, can be used as the drying method.
When performing warm air drying, the speed of the warm air may be set as appropriate so that the coating composition can be dried quickly and the coating film (gel film) of the coating composition does not collapse. Specifically, 0.5 to 200 m / min is preferable, 0.75 to 200 m / min is more preferable, and 1 to 200 m / min is particularly preferable.
Further, the temperature of the hot air may be appropriately set at a temperature at which the support 20b is not deformed and the coating composition can be dried quickly. Specifically, the film surface temperature is preferably 1 to 120 ° C., more preferably 2 to 115 ° C., and particularly preferably 3 to 110 ° C.

When drying the facilitated transport film 20a by heating the support 20b, the temperature at which the support 20b is not deformed and the coating composition can be quickly dried may be appropriately set. Moreover, you may use blowing of dry air together with the heating of the support body 20b.
Specifically, drying of the facilitated transport film 20a by heating the support 20b is preferably performed at a temperature of the support 20b of 60 to 120 ° C, more preferably 60 to 90 ° C, and more preferably 70 to 80 ° C. It is particularly preferable to carry out as In this case, the film surface temperature is preferably 15 to 80 ° C., more preferably 30 to 70 ° C.

When the coating composition is dried to produce the facilitated transport membrane 20a, that is, the acidic gas separation membrane 20, the acidic gas separation membrane 20 is wound into a roll.

In the above example, the support 20b on which the carrier diffusion suppression layer 20c is formed is temporarily wound, and the support 20b on which the carrier diffusion suppression layer 20c is formed is sent out from this roll to form the facilitated transport film 20a. is doing.
However, in addition to this, the support 20b on which the carrier diffusion suppressing layer 20c is formed is not wound up, but is transported in the longitudinal direction as it is to form the facilitated transport film 20a to produce the acidic gas separation film 20, May be.

In the acidic gas separation membrane 20 shown in FIG. 3, the facilitated transport membrane 20a is formed on the carrier diffusion suppression layer 20c, but the present invention is not limited to this.
For example, a part of the facilitated transport film 20a may be formed (impregnated) inside the support 20b, or the facilitated transport film 20a may be entirely formed (impregnated) inside the support 20b. May be. Alternatively, the facilitated transport film 20a may be supported by a nonwoven fabric or the like and supported by a porous support.
In this case, the carrier diffusion suppression layer 20c may be formed so as to support the facilitated transport film 20a in the direction in which the pressure by the source gas G is applied.

Hereinafter, in the separation module 10, a method for producing the laminated body 14 a including the acidic gas separation membrane 20, the supply gas flow path member 24 and the permeate gas flow path member 26, and a winding method of the laminated body 14 a, that is, lamination A method for producing the wound body 14 will be described.
In FIGS. 4A to 8 used in the following description, the supply gas flow path member 24 and the permeate gas flow path member 26 have end faces (end portions) in order to simplify the drawings and clearly show the configuration. Only the net is shown.

First, as conceptually shown in FIGS. 4 (A) and 4 (B), the extending direction of the central cylinder 12 and the short direction coincide with each other, and the fixing means 34 such as an adhesive is attached to the central cylinder 12. Is used to fix the end of the permeating gas flow path member 26.
Here, as described above, it is preferable that the circumferential surface of the center tube 12 is provided with slits (not shown) along the axial direction. In this case, a distal end portion of a permeating gas channel member 26 to be described later is inserted into the slit, and is fixed to the inner peripheral surface of the center tube 12 by fixing means. According to this configuration, when the laminated body including the permeating gas channel member 26 is wound around the central tube 12, the inner peripheral surface of the central tube 12 and the permeating gas channel Friction with the member 26 can prevent the permeate gas flow path member 26 from coming out of the slit, that is, the permeate gas flow path member 26 is fixed.

On the other hand, as conceptually shown in FIG. 5, the acidic gas separation membrane 20 produced as described above is folded in half with the facilitated transport membrane 20a inside, and the supply gas flow path member 24 is sandwiched therebetween. That is, the holding body 36 is manufactured in which the supply gas flow path member 24 is held between the acidic gas separation membranes 20 folded in half. In this case, the acidic gas separation membrane 20 is not equally folded in half, but is folded in half so that one is slightly longer as shown in FIG.
In order to prevent the facilitated transport membrane 20a from being damaged by the supply gas flow path member 24, a sheet-like protective member folded in half is disposed in the trough where the acidic gas separation membrane 20 is folded in half. preferable. Examples of the protective member include Kapton tape.

Further, an adhesive 30a to be the adhesive layer 30 is applied to the shorter surface of the acid gas separation membrane 20 folded in half (the surface of the support 20b).
Here, as shown in FIG. 5, the adhesive 30 a (adhesive layer 30) extends in the vicinity of both ends in the width direction (arrow x direction) and extends in the entire winding direction (arrow y direction). Furthermore, it is applied to the entire region in the width direction in the vicinity of the end portion opposite to the folded portion, and is applied in a band shape.

Next, as conceptually shown in FIGS. 6 (A) and 6 (B), the surface coated with the adhesive 30a is directed to the permeating gas flow path member 26, and the folded side is directed to the central cylinder 12. The sandwiching body 36 is laminated on the permeate gas flow path member 26 fixed to the central cylinder 12, and the permeate gas flow path member 26 and the acidic gas separation membrane 20 (support 20b) are bonded.

Further, as shown in FIGS. 6A and 6B, an adhesive 30a to be the adhesive layer 30 is applied to the upper surface (the surface of the longer support 20b) of the sandwiched sandwich 36. In the following description, the direction opposite to the permeating gas flow path member 26 first fixed to the central cylinder 12 by the fixing means 34 (upper side in the drawing) is also referred to as the upper side.
As shown in FIGS. 6 (A) and 6 (B), the adhesive 30a on this surface also extends in the vicinity of both ends in the width direction and is applied in a strip shape in the vicinity of both ends in the width direction. Furthermore, it extends in the entire region in the width direction in the vicinity of the end opposite to the folded portion and is applied in a band shape.

Next, as conceptually shown in FIG. 7, the permeate gas flow path member 26 is laminated on the sandwich 36 applied with the adhesive 30a, and the acidic gas separation membrane 20 (support 20b) and the permeate gas flow are laminated. The road member 26 is bonded to form the laminated body 14a.
Note that a plurality of permeate gas channel members 26 may be used as necessary.

Next, as shown in FIG. 5, as shown in FIG. 5, a sandwiching body 36 in which the supply gas flow path member 24 is sandwiched between the acidic gas separation membranes 20 is produced, and an adhesive 30 a to be the adhesive layer 30 is applied. The permeated gas flow path member 26 and the sandwiching body 36 that are finally stacked are stacked and bonded with the side to which the adhesive is applied facing down.
Further, similarly to the above, an adhesive 30a is applied to the upper surface of the laminated sandwiching body 36 as shown in FIGS. 6A and 6B, and then, as shown in FIG. Then, the permeating gas flow path member 26 is laminated and bonded, and the second laminated body 14a is laminated.

The following steps of FIGS. 5 to 7 are repeated, and a predetermined number of laminated bodies 14a are laminated as conceptually shown in FIG.
As shown in FIG. 8, it is preferable that the laminated body 14a is laminated so as to be gradually separated from the central tube 12 in the winding direction as it goes upward. Thereby, the laminated body 14a is easily wound around the central cylinder 12, and the end of the permeate gas flow path member 26 on the central cylinder 12 side or the vicinity of the end is preferably in contact with the central cylinder 12. it can.

When a predetermined number of the laminated bodies 14a are laminated, as shown in FIG. The adhesive 38b is applied between the sandwiching body 36 and the adhesive 36b.
Next, as shown by an arrow yw in FIG. 8, the laminated body 14 a is wound around the central cylinder 12 so as to wind the laminated body 14 a.
When the winding is completed, the permeate gas passage member 26 on the outermost periphery is maintained for a predetermined time in a state where tension is applied in the pulling-out direction, that is, the direction of squeezing and the adhesive 30a and the like are dried. The outermost permeating gas channel member 26 is the lowermost permeating gas channel member 26 fixed to the central cylinder 12 first.
When a predetermined time has elapsed, the outermost permeate gas channel member 26 is fixed by ultrasonic welding or the like at a position where it has made one round, and the excess permeate gas channel member 26 outside the fixed position is cut. Thus, the laminated body 14 is obtained by winding the laminated body 14a around the central cylinder.

As described above, the raw material gas G is supplied from the end of the supply gas flow path member 24, and the acidic gas Gc passes through the acidic gas separation membrane 20 by being transported in the stacking direction, and passes through the permeated gas flow. It flows into the road member 26, flows through the permeate gas flow path member 26, and reaches the central cylinder 12.

Here, the adhesive 30a is applied to the support 20b, which is a porous body, and the net-like permeating gas channel member 26 is bonded to the adhesive 30a. Therefore, the adhesive 30a penetrates (impregnates) the support 20b and the permeating gas flow path member 26, and the adhesive layer 30 is formed inside of both.
Further, as described above, the adhesive layer 30 (adhesive 30a) is formed in a strip shape extending in the entire vicinity in the winding direction in the vicinity of both ends in the width direction. Further, the adhesive layer 30 extends across the entire width direction in the vicinity of the end portion on the side opposite to the folded portion on the central tube 12 side so as to cross the adhesive layer 30 in the vicinity of both ends in the width direction in the width direction. Then, it is formed in a band shape. That is, the adhesive layer 30 is formed so as to surround the outer peripheries of the permeating gas flow path member 26 and the support 20b by opening the central tube 12 side. In addition, the permeating gas channel member 26 is sandwiched between the facilitated transport films 20a.
As a result, an envelope-like flow path that opens on the side of the central tube 12 is formed in the permeating gas flow path member 26 of the laminate 14a. Therefore, the acidic gas Gc that has passed through the acidic gas separation membrane 20 and has flowed into the permeate gas flow path member 26 flows through the permeate gas flow path member 26 toward the central cylinder 12 without flowing out, It flows into the center tube 12 from the through hole 12a.
That is, the adhesive layer 30 acts not only for bonding but also as a sealing portion for sealing the acidic gas Gc to a predetermined channel in the permeating gas channel member 26 and the like.

In the separation module 10 of the present invention, various known adhesives can be used as long as the adhesive layer 30 (adhesive 30a) has sufficient adhesive strength, heat resistance, and moisture resistance.
Examples include epoxy resins, vinyl chloride copolymers, vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinylidene chloride copolymers, vinyl chloride-acrylonitrile copolymers, butadiene-acrylonitrile copolymers, polyamide resins, polyvinyl butyral. Preferred examples include polyesters, cellulose derivatives (nitrocellulose, etc.), styrene-butadiene copolymers, various synthetic rubber resins, phenol resins, urea resins, melamine resins, phenoxy resins, silicone resins, urea formamide resins, and the like. .

The adhesive 30a to be the adhesive layer 30 may be applied once, but preferably, an adhesive diluted with an organic solvent such as acetone is applied first, and only the adhesive is applied thereon. preferable. In this case, the adhesive diluted with an organic solvent is preferably applied in a wide width, and the adhesive is preferably applied in a narrower width.

In the separation module 10 of the present invention, a telescope prevention plate (telescope prevention member) 16 is disposed at both ends of the laminated body 14 produced in this way.
As described above, the telescope prevention plate 16 is so-called that the laminated body 14 is pressed by the raw material gas G, the supply-side end surface is pushed in a nested manner, and the opposite-side end surface protrudes in a nested manner. It is a member for preventing the telescope phenomenon.

In the present invention, as the telescoping prevention plate 16, various known types used for spiral type separation modules can be used.
In the illustrated example, the telescope prevention plate includes an annular outer ring portion 16a, an annular inner ring portion 16b arranged in the outer ring portion 16a so as to coincide with the center, an outer ring portion 16a and an inner ring. And a rib (spoke) 16c for connecting and fixing the portion 16b. The central cylinder 12 around which the laminate in which the laminate 14a is laminated is wound passes through the inner ring portion 16b.
In the illustrated example, the ribs 16c are provided radially at equal angular intervals from the center of the outer ring part 16a and the inner ring part 16b, and between the outer ring part 16a and the inner ring part 16b and each rib 16c. Is an opening 16d through which the source gas G or the residual gas Gr passes.

The telescoping prevention plate 16 may be disposed in contact with the end face of the laminated body 14.
However, the telescope prevention plate 16 and the end face of the laminated body 14 have a slight gap in order to use the entire end face of the laminated body 14 for supplying the source gas and discharging the residual gas Gr. Are preferably arranged.

Various materials having sufficient strength, heat resistance and moisture resistance can be used as the material for forming the telescope prevention plate 16.
Specifically, a metal material, a resin material, ceramics, etc. are illustrated suitably.
Examples of the metal material include stainless steel (SUS), aluminum, aluminum alloy, tin, and tin alloy.
Examples of the resin material include polyethylene resin, polypropylene resin, aromatic polyamide resin, nylon 12, nylon 66, polysulfin resin, polytetrafluoroethylene resin, polycarbonate resin, acrylic / butadiene / styrene resin, acrylic / ethylene / styrene resin, Examples include epoxy resins, nitrile resins, polyether ether ketone resins (PEEK), polyacetal resins (POM), polyphenylene sulfide (PPS), and the like.
Examples of the resin material include fiber reinforced plastics using these resins. Examples of the fiber include glass fiber, carbon fiber, stainless steel fiber, and aramid fiber. The fiber is preferably a long fiber. More specifically, examples of the fiber reinforced plastic include long glass fiber reinforced polypropylene and long glass fiber reinforced polyphenylene sulfide.
Examples of ceramics include zeolite and alumina.

The covering layer 18 covers the peripheral surface of the laminated body 14 and blocks the discharge of the raw material gas G and the residual gas Gr from outside the peripheral surface, that is, the end surface of the laminated body 14. It is.
The covering layer 18 may be provided to cover not only the peripheral surface of the laminated body 14 but also the telescope prevention plate as necessary.

As the coating layer 18, various materials that can shield the raw material gas G and the like can be used. The covering layer 18 may be a cylindrical member or may be configured by winding a wire or a sheet-like member.
As an example, a wire made of FRP (reinforced fiber plastic) is impregnated with the adhesive used for the adhesive layer 30 described above, and the wire impregnated with the adhesive is laminated in multiple layers as necessary without gaps. The coating layer 18 wound around the body roll 14 is illustrated. There are no limitations on the fiber or matrix resin used in FRP. As an example, examples of the fiber include glass fiber, carbon fiber, Kevlar, Dyneema, etc. Among them, glass fiber is particularly preferable. Examples of the matrix resin include an epoxy resin, a polyamide resin, an acrylate resin, and an unsaturated polyester resin, and an epoxy resin is preferable from the viewpoint of heat resistance and hydrolysis resistance.
In this case, if necessary, a sheet shape such as a Kapton tape for preventing penetration of the adhesive into the laminated body 14 between the coating layer 18 and the laminated body 14. A member may be provided.

The acid gas separation module of the present invention has been described in detail above. However, the present invention is not limited to the above-described example, and various improvements and modifications may be made without departing from the gist of the present invention. Of course.

Hereinafter, specific examples of the present invention will be given and the acid gas separation module of the present invention will be described in more detail.

[Example 1]
<Preparation of the coating composition used as the carrier diffusion suppression layer 20c>
80% by mass of crosslinkable polydimethylsiloxane (KF102, manufactured by Shin-Etsu Chemical Co., Ltd.), 19% by mass of non-crosslinkable fluorine-modified polydimethylsiloxane (X22-821, manufactured by Shin-Etsu Chemical Co., Ltd., weight average molecular weight 8000), photoacid A composition containing 1% by mass of a generator (I0591, manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as a coating composition to be the carrier diffusion suppression layer 20c.

<Adjustment of coating composition to be facilitated transport film 20a>
3.3% by mass of polyvinyl alcohol-polyacrylic acid copolymer (Clastomer AP-20, manufactured by Kuraray Co., Ltd.) and 0.016% by mass of a crosslinking agent (25% by mass glutaraldehyde aqueous solution, manufactured by Wako Pure Chemical Industries, Ltd.) An aqueous solution was prepared. To this aqueous solution, 1M hydrochloric acid was added until the pH reached 1.7 to cause crosslinking.
After crosslinking, a 40% aqueous cesium carbonate solution (manufactured by Rare Metals) was added so that the concentration of cesium carbonate was 6.0% by mass. That is, in this example, cesium carbonate serves as a carrier for the facilitated transport film 20a.
Furthermore, 0.004% by mass of a surfactant (1% by mass of Lapisol A-90 manufactured by NOF Corporation) was added, and the mixture was stirred and degassed to prepare a coating composition to be the facilitated transport film 20a.

<Preparation of Acid Gas Separation Membrane 20>
<< Formation of Carrier Diffusion Suppression Layer 20c >>
As the support 20b, a support roll formed by winding a long laminate (manufactured by GE), which is formed by laminating a porous film on the surface of a PP nonwoven fabric, was prepared. This porous membrane is porous PTFE.
A general film forming apparatus that has a coating apparatus (roll coater), a drying apparatus, and an ultraviolet irradiation apparatus and that forms a film by a coating method using RtoR is loaded with this support roll, and the support 20b is placed in a predetermined transport path. The tip was wound around a take-up shaft. Moreover, the coating composition used as the carrier diffusion suppression layer 20c prepared previously was filled in the material tank of the coating means.
With this film forming apparatus, the coating composition that becomes the carrier diffusion suppression layer 20c is applied by the coating apparatus while the support 20b is transported in the longitudinal direction, the coating composition is dried by the drying apparatus, and the coating composition is dried by the ultraviolet irradiation apparatus. Was cured to form a carrier diffusion suppression layer 20c on the support 20b and wound into a roll.
Application | coating of the coating composition was performed at normal temperature. The coating amount of the coating composition was set such that the thickness of the carrier diffusion suppression layer 20c after curing was 5 μm according to experiments performed in advance. The conveyance speed of the support 20b was 30 m / min.

After forming the carrier diffusion suppression layer 20c in this way, the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer 20c was confirmed by fluorescent X-ray elemental analysis (XRF). As a result, the ratio of fluorine atoms to silicon atoms was 15% in atomic ratio.

<< Formation of facilitated transport film 20a >>
A roll formed by winding the support roll and the support 20b on which the carrier diffusion suppression layer 20c was formed was removed from the film forming apparatus in which the carrier diffusion suppression layer 20c was formed on the support 20b.
A general film forming apparatus having a coating apparatus (roll coater) and a drying apparatus that forms a film by a coating method using RtoR is loaded with a roll formed by winding the support 20b on which the carrier diffusion suppression layer 20c is formed. Then, the support 20b on which the carrier diffusion suppression layer 20c was formed was inserted through a predetermined conveyance path, and the tip was wound around the winding shaft. Moreover, the coating composition which becomes the facilitated-transport film | membrane 20a prepared previously was filled in the material tank of the coating device.
Next, the film forming apparatus applies the coating composition by the coating apparatus while transporting the support 20b in the longitudinal direction, and the coating composition is dried by the drying apparatus, thereby promoting the carrier diffusion suppressing layer 20c. By forming the transport membrane 20a, an acid gas separation membrane 20 having a support 20b, a carrier diffusion suppression layer 20c, and a facilitated transport membrane 20a as shown in FIGS. 3 (A) and 3 (B) is prepared. And wound into a roll.
The coating amount of the coating composition was such that the thickness of the facilitated transport film 20a formed by drying was 30 μm, according to experiments performed in advance.

<Production of separation module>
First, as shown in FIGS. 4A and 4B, a permeate gas flow path member 26 was fixed to the center tube 12 made of SUS with an adhesive. As the permeating gas channel member 26, a PP net having a thickness of 0.2 mm was used.

On the other hand, the produced acidic gas separation membrane 20 was cut into a predetermined length and folded in half with the facilitated transport membrane 20a inside. As shown in FIG. 5, the half-folding was performed so that one acidic gas separation membrane 20 was slightly longer. Kapton tape was attached to the valley of the acid gas separation membrane 20 folded in half, and the end of the supply gas flow path member 24 was reinforced so as not to damage the valley of the facilitated transport membrane 20a.
Subsequently, the supply gas flow path member 24 was sandwiched between the folded acidic gas separation membranes 20 to produce a sandwiching body 36. As the supply gas flow path member 24, a PP net having a thickness of 0.44 mm was used.

As shown in FIG. 5, on the side of the porous support 20b on which the acidic gas separation membrane 20 of the sandwich 36 is shorter, in the vicinity of both ends in the width direction (arrow x direction), the winding direction (arrow y direction). The adhesive 30a was applied to the entire region in the width direction in the vicinity of the end portion on the side opposite to the folded portion in the winding direction. As the adhesive 30a, an adhesive made of an epoxy resin (E120HP manufactured by Henkel Japan) was used.
Next, with the side to which the adhesive 30a is applied facing downward, as shown in FIGS. 6A and 6B, the sandwiching body 36 and the permeating gas flow path member 26 fixed to the central cylinder 12 are provided. Laminated and glued.
Next, as shown in FIGS. 6 (A) and 6 (B), winding is performed on the upper surface of the acidic gas separation membrane 20 of the sandwiching body 36 laminated on the permeating gas flow path member 26 in the vicinity of both ends in the width direction. The adhesive 30a was applied so as to extend over the entire region in the width direction and in the vicinity of the end portion on the opposite side of the folded portion in the winding direction. Further, as shown in FIG. 7, a permeate gas flow path member 26 is laminated on the acidic gas separation membrane 20 coated with the adhesive 30a and bonded to form the first layered product 14a. did.

In the same manner as described above, another sandwich member 36 shown in FIG. 5 was produced, and similarly, the adhesive 30a was similarly applied to the porous support 20b side of the short acid gas separation membrane 20. Next, in the same manner as in FIGS. 6A and 6B, the side to which the adhesive 30 a is applied is directed toward the first layered body 14 a (the permeated gas flow path member 26) formed first, The sandwiching body 36 was laminated on the first layered body 14a (permeating gas flow path member 26) and adhered. Further, an adhesive 30a is applied to the upper surface of the sandwiching body 36 in the same manner as in FIGS. 6A and 6B, and a permeating gas channel member 26 is laminated thereon, as in FIG. Then, the second layered product 14a was formed by bonding.
Further, in the same manner as the second layer, the third layered body 14a was formed on the second layered body 14a.

After laminating the three-layer laminate 14a on the permeate gas flow path member 26 fixed to the central cylinder 12, an adhesive 38a is applied to the peripheral surface of the central cylinder 12, as shown in FIG. The adhesive 38b was applied on the permeating gas flow path member 26 between the central cylinder 12 and the lowermost layered laminate 14a. The adhesives 38a and 38b were the same as the adhesive 30a.
Next, by rotating the central cylinder 12 in the direction of the arrow yw in FIG. 8, the laminated body 14 a having three layers was wound around the central cylinder 12 in a multiple manner so as to be a laminated body 14.

After cutting the both ends of the produced laminated body 14 and aligning the end faces, the center tube 12 is inserted into the inner ring portion 16b at both ends of the laminated body 14 and shown in FIG. A telescoping prevention plate 16 having a thickness of 2 cm was attached. The telescope prevention plate 16 was made of PPS containing 40% by mass of glass fiber. The distance between the telescope prevention plate 16 and the laminate wound product 14 was 1 mm.
Furthermore, the coating layer 18 was formed by winding the FRP resin tape around the peripheral surface of the telescope prevention plate 16 and the peripheral surface of the laminated body 14 to produce the separation module 10. The membrane area of the prepared separation module 10 was 1.2 m ² (design value) in total.

[Example 2]
In the preparation of the coating composition to be the carrier diffusion suppressing layer 20c, as a non-crosslinkable fluorine-modified polydimethylsiloxane, instead of X22-821 made by Shin-Etsu Chemical, FL-100-1000cs made by Shin-Etsu Chemical (weight average) A coating composition to be the carrier diffusion suppression layer 20c was prepared in the same manner as in Example 1 except that molecular weight 40000) was used.
The separation module 10 was produced by producing the acidic gas separation membrane 20 in the same manner as in Example 1 except that the carrier diffusion suppression layer 20c was formed using this coating composition.
In the same manner as in Example 1, the amount of fluorine atoms relative to silicon atoms in the carrier diffusion suppression layer 20c was confirmed. As a result, the ratio of fluorine atoms to silicon atoms was 15% in atomic ratio.

[Example 3]
In the preparation of the coating composition to be the carrier diffusion suppressing layer 20c, the amount of the crosslinkable polydimethylsiloxane is 50% by mass, the amount of the non-crosslinkable fluorine-modified polydimethylsiloxane is 49% by mass, and the amount of the photoacid generator is A coating composition to be the carrier diffusion suppression layer 20c was prepared in the same manner as in Example 1 except that the amount was 1% by mass.
The separation module 10 was produced by producing the acidic gas separation membrane 20 in the same manner as in Example 1 except that the carrier diffusion suppression layer 20c was formed using this coating composition.
In the same manner as in Example 1, the amount of fluorine atoms relative to silicon atoms in the carrier diffusion suppression layer 20c was confirmed. As a result, the ratio of fluorine atoms to silicon atoms was 30% in terms of atomic ratio.

[Comparative Example 1]
In the preparation of the coating composition to be the carrier diffusion suppressing layer 20c, the amount of the crosslinkable polydimethylsiloxane is 30% by mass, the amount of the non-crosslinkable fluorine-modified polydimethylsiloxane is 69% by mass, and the amount of the photoacid generator is A coating composition to be a carrier diffusion suppressing layer was prepared in the same manner as in Example 1 except that the amount was 1% by mass.
An acidic gas separation membrane was produced in the same manner as in Example 1 except that a carrier diffusion suppression layer was formed using this coating composition, and a separation module was produced.
As in Example 1, the amount of fluorine atoms relative to silicon atoms in the carrier diffusion suppression layer was confirmed. As a result, the ratio of fluorine atoms to silicon atoms was 45% in terms of atomic ratio.

[Comparative Example 2]
An acidic gas separation membrane was produced in the same manner as in Example 1 except that the carrier diffusion suppression layer 20c was not formed, and a separation module was produced.

[Comparative Example 3]
In the preparation of the coating composition to be the carrier diffusion suppressing layer 20c, non-crosslinkable fluorine-modified polydimethylsiloxane was not added, the amount of the crosslinkable polydimethylsiloxane was 99% by mass, and the amount of the photoacid generator was 1% by mass. The coating composition used as a carrier diffusion suppression layer was prepared like Example 1 except having set it as%.
An acidic gas separation membrane was produced in the same manner as in Example 1 except that a carrier diffusion suppression layer was formed using this coating composition, and a separation module was produced.

[Evaluation]
The separation module 10 thus produced was evaluated for durability over time as follows.
<Durability over time>
The raw material gas G was supplied to each separation module 10 under the conditions of a flow rate of 0.32 L / min, a temperature of 130 ° C., and a total pressure of 1.5 MPa. As the source gas G, a mixed gas (partial pressure ratio) of N ₂ : CO ₂ : H ₂ O = 66: 21: 13 was used. A through hole for supplying a sweep gas was formed at the end of the central cylinder 12 on the raw material gas permeation side, and Ar gas having a flow rate of 0.6 L / min was supplied as a sweep gas from here.
The gas (acid gas Gc and residual gas Gr) that has permeated through the separation module 10 was analyzed by a gas chromatograph at the time when 1 hour passed after starting the supply of the raw material gas G and at the time when 10 hours passed, and CO ₂ / N ₂ separation factor (α) was measured.

The rate of change in the CO ₂ / N ₂ separation factor (α) was calculated at the time of 1 hour and at the time of 10 hours, and the pressure durability was evaluated.
Rate of change =
[(Value at 1 hour elapsed time-Value at 10 hour elapsed time) / Value at 1 hour elapsed time] × 100
The results are shown in the table below.
In Comparative Example 2 having no carrier diffusion suppression layer, the facilitated transport film 20a dropped off, and measurement could not be performed.

As shown in the above table, the carrier diffusion suppression layer 20c of the acidic gas separation membrane 20 contains a fluorine-modified silicone compound, and the carrier diffusion suppression layer 20c has a ratio of fluorine atoms to silicon atoms in an atomic ratio of 5 to 5. The separation module 10 of the present invention that is 40% has good durability over time.
In particular, although Example 1 has the same amount of fluorine atoms with respect to silicon atoms as Example 2, the fluorine-modified silicone compound has a molecular weight of 10,000 or less, and therefore has better durability over time than Example 2. ing. In Example 1, although the fluorine-modified silicone compound is the same as that in Example 3, the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppression layer 20c is within a preferable range of 10 to 20% in terms of atomic ratio. It has better durability over time than Example 3.
In contrast, Comparative Example 1 in which the amount of fluorine atoms relative to silicon atoms in the carrier diffusion suppression layer 20c is too high is low in durability over time as compared with the separation module of the present invention, and the carrier diffusion suppression layer is a fluorine-modified silicone compound. Comparative Example 3 containing no further lower durability over time.
In Comparative Example 2 that does not have a carrier diffusion suppression layer, the facilitated transport film 20a dropped off, and the measurement could not be performed as described above.
From the above results, the effects of the present invention are clear.

It can be suitably used for hydrogen gas production and natural gas purification.

DESCRIPTION OF SYMBOLS 10 (Acid gas) separation module 12 Center tube 14 Laminated body roll 14a Laminated body 16 Telescope prevention board 16a Outer ring part 16b Inner ring part 16c Rib 16d Opening part 18 Covering layer 20 Acid gas separation film 20a Accelerated transport film 20b Porous Support 20c Carrier Diffusion Suppression Layer 24 Supply Gas Channel Member 26 Permeate Gas Channel Member 30 Adhesive Layer 30a Adhesive 34 Fixing Means

Claims

A porous support, a carrier that reacts with an acidic gas, a facilitated transport film containing a hydrophilic compound for supporting the carrier, and a carrier diffusion suppression layer that prevents the carriers of the facilitated transport film from diffusing. An acidic gas separation membrane, and a supply gas flow path member serving as a flow path for the source gas,
The acidic gas separation module, wherein the carrier diffusion suppressing layer contains a fluorine-modified silicone compound, and the ratio of fluorine atoms to silicon atoms in the carrier diffusion suppressing layer is 5 to 40% by atomic ratio.
2. The acidic gas separation module according to claim 1, wherein a ratio of fluorine atoms to silicon atoms in the fluorine-modified silicone compound contained in the carrier diffusion suppressing layer is 20 to 300% by atomic ratio.
The acid gas separation module according to claim 1 or 2, wherein the fluorine-modified silicone compound has a weight average molecular weight of 20000 or less.
The acid gas separation module according to any one of claims 1 to 3, wherein the carrier is an alkali metal compound.
The acidic gas separation module according to any one of claims 1 to 4, wherein the carrier diffusion suppression layer further contains an organopolysiloxane.
The acidic gas separation module according to any one of claims 1 to 5, wherein the acidic gas separation module is a spiral type formed by winding a laminate including the acidic gas separation membrane and the supply gas flow path member.
The acid gas separation module according to any one of claims 1 to 5, wherein the acid gas separation module has a flat plate shape in which a laminate including the acid gas separation membrane and the supply gas flow path member is maintained in a flat plate shape.