JP2017225944A - Polymer film and method for producing the same, and method of separating carbon dioxide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymer film for separating carbon dioxide from another gas with high selectivity and a method for producing the same, and a gas separating method using the polymer film.SOLUTION: A carbon dioxide is separated using a polymer film containing a high molecular weight polymer that is obtained by polymerization of a polyfunctional polymerizable monomer, and at least one compound selected from the group consisting of polyethylene polyamines.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a polymer membrane for selectively separating carbon dioxide from a carbon dioxide-containing mixed gas, a method for producing the polymer membrane, and a gas separation method using the polymer membrane.

  Conventionally, since a polymer material has gas permeability unique to the material, it is known that a gas component can be separated by a film made of the polymer material (see, for example, Non-Patent Document 1). Gas separation membranes utilizing this property are energy-saving and space-saving separation technologies, and have the advantage of easy maintenance of the apparatus, and are used in various fields.

  On the other hand, in recent years, a technique for separating and collecting carbon dioxide, which is a cause of global warming, before being discharged into the atmosphere from a large-scale source such as a power plant has been energetically studied. For example, a method for absorbing carbon dioxide with an amine has been studied at a demonstration level. However, it requires a large amount of energy for heating and the amine is a deleterious substance.

  Therefore, the membrane separation method is expected as the next generation carbon dioxide separation and recovery technology. However, there has been no practical application yet, and Polaris (registered trademark) of MTR in the United States has reached the pilot test level only (see, for example, Non-Patent Document 2).

  The reason for not reaching practical use is that the carbon dioxide permeation rate and carbon dioxide selectivity do not reach the required physical property values. In particular, the polymer membrane has a lower carbon dioxide permeation rate than the inorganic membrane. That is a problem. However, polymer membranes are relatively easy to prepare and chemically modify, have excellent mass productivity and molding processability, and are low in cost. Therefore, membrane separation methods using polymer membranes for carbon dioxide separation and recovery are desired. It was rare.

  Thus, polymer membranes with improved carbon dioxide selectivity have been studied.

  For example, a method is proposed in which a polymer layer in which a gel layer obtained by adding 2,3-diaminopropionic acid to a polyvinyl alcohol-polyacrylic acid copolymer gel membrane is supported on a hydrophilic porous membrane is used for carbon dioxide separation. (For example, refer to Patent Document 1).

  In addition, for example, a polymer membrane containing a polyamidoamine dendrimer (PAMAM) as a carbon dioxide affinity substance and formed from a crosslinked PEG obtained by photocrosslinking polymerization of polyethylene glycol dimethacrylate (PEGDMA) is separated from carbon dioxide. A method used for the above has also been proposed (see, for example, Patent Document 2).

  However, industrially, a higher carbon dioxide selectivity is desired, and the carbon dioxide selectivity in these methods cannot be said to be sufficient. A polymer membrane with improved carbon selectivity has been desired.

JP 2008-036463 A JP 2009-185118 A New development of gas separation technology, Toray Research Center Research Division, Toray Research Center Co., Ltd., 1990, pages 345-362 Journal of Membrane Science 359 (2010) 126-139

  An object of this invention is to provide the polymer membrane for isolate | separating a carbon dioxide from other gas with high selectivity, its manufacturing method, and the gas separation method using this polymer membrane.

  As a result of intensive research to solve the above problems, the present inventors have polymerized a polyfunctional polymerizable monomer in the presence of a specific amine compound to obtain a polymer. A polymer membrane in which the amine compound is physically immobilized is formed in the body, and it has been found that the polymer membrane has high selectivity for carbon dioxide, and the present invention has been completed.

  That is, the present invention is a polymer membrane as shown below, a method for producing the same, and a method for separating carbon dioxide.

  [1] A polymer film comprising a polymer of a polyfunctional polymerizable monomer and at least one compound selected from the group consisting of polyethylene polyamines.

  [2] The polyfunctional polymerizable monomer is at least one selected from the group consisting of polyfunctional (meth) acrylamides, polyfunctional (meth) acrylates, polyfunctional vinyl ethers, and divinylbenzene. The polymer film according to [1] above.

  [3] The polyfunctional polymerizable monomer is at least one selected from the group consisting of di (meth) acrylates, tri (meth) acrylates and tetra (meth) acrylates. 1].

  [4] The polyfunctional polymerizable monomer is (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane di The polymer film as described in [1] above, which is at least one selected from the group consisting of (meth) acrylate and pentaerythritol di (meth) acrylate.

  [5] The above-mentioned [1] to [4], wherein the polymer of the polyfunctional polymerizable monomer is a polymer of a polyfunctional polymerizable monomer and a monofunctional polymerizable monomer. The polymer film according to any one of the above.

  [6] Monofunctional polymerizable monomers are monofunctional (meth) acrylamides, monofunctional (meth) acrylates, monofunctional vinyl ethers, monofunctional N-vinyl compounds, monofunctional vinyl compounds, and monofunctional The polymer film as described in [5] above, which is at least one selected from the group consisting of α, β-unsaturated compounds.

  [7] Monofunctional polymerizable monomer is methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, methoxyethyl (meth) acrylate , At least one selected from the group consisting of methoxy polyethylene glycol (meth) acrylate, (meth) acrylic acid, N, N-dimethylaminoethyl (meth) acrylate, (poly) ethylene glycol methacrylate and polypropylene glycol (meth) acrylate The polymer film as described in [5] above, wherein

  [8] The polymer film as described in [5] above, wherein the polyfunctional polymerizable monomer is polyethylene glycol dimethacrylate and the monofunctional polymerizable monomer is polyethylene glycol methacrylate.

  [9] The polyethylene polyamine is at least one selected from the group consisting of diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and pentaethylenehexamine (PEHA). The polymer film according to any one of [1] to [9].

  [10] A gas separation membrane comprising the polymer membrane according to any one of [1] to [10].

  [11] A method for producing a polymer film, wherein a polymerization reaction of a polyfunctional polymerizable monomer is carried out in the presence of at least one compound selected from the group consisting of polyethylene polyamines.

  [12] The method for producing a polymer film as described in [11] above, wherein a monofunctional polymerizable monomer is further used as a polymerization component.

  [13] The method for producing a polymer film according to [11] or [12], wherein the polymerization reaction is a photopolymerization reaction or a thermal polymerization reaction.

  [14] including a step of bringing a mixed gas containing carbon dioxide into contact with the polymer membrane according to any one of [1] to [9] above, and selectively allowing carbon dioxide in the mixed gas to permeate. A carbon dioxide separation method characterized by the above.

  ADVANTAGE OF THE INVENTION According to this invention, the polymer membrane which can isolate | separate carbon dioxide from other gas with high selectivity, and its manufacturing method are provided. The present invention also provides a method for efficiently separating carbon dioxide from other gases using the polymer membrane.

  The polymer membrane of the present invention is stable because the amine compound having carbon dioxide separation ability is not physically supported on the surface of the polymer membrane but physically immobilized in the polymer membrane. It has the characteristic that the property is very excellent.

It is the schematic of the gas separation apparatus used in the Example. In the figure, GC means gas chromatography.

  Hereinafter, the present invention will be described in detail.

  The polymer film of the present invention contains a polymer of a polyfunctional polymerizable monomer (hereinafter referred to as “polymer polymer”) and at least one compound selected from the group consisting of polyethylene polyamines. Is the feature. Specifically, at least one compound selected from the group consisting of polyethylene polyamines is physically immobilized in the structure of the polymer to form the polymer film of the present invention.

  First, the polymer in the present invention will be described.

  In the present invention, the high molecular polymer plays a role of maintaining the shape as a film while retaining at least one compound selected from the group consisting of polyethylene polyamines in its structure.

  The polyfunctional polymerizable monomer is not particularly limited as long as it is a polymerizable compound having two or more carbon-carbon unsaturated bonds. Examples thereof include polyfunctional acrylic monomers such as polyfunctional (meth) acrylamides and polyfunctional (meth) acrylates, polyfunctional vinyl ethers such as polyfunctional vinyl ethers and divinylbenzene, and the like. These polyfunctional polymerizable monomers can be used alone or in combination of two or more.

  Examples of the polyfunctional (meth) acrylamides include N, N ′-(1,2-dihydroxyethylene) bisacrylamide, ethidium bromide-N, N′-bisacrylamide, ethidium bromide-N, N′-bismethacrylamide, N, N′-ethylenebisacrylamide, N, N′-methylenebisacrylamide and the like can be mentioned.

  Examples of the polyfunctional (meth) acrylates include di (meth) acrylates, tri (meth) acrylates, and tetra (meth) acrylates.

  Examples of the di (meth) acrylates include (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and trimethylolpropane di (meta). And alkylene glycol di (meth) acrylates such as acrylate and pentaerythritol di (meth) acrylate.

  Examples of the tri (meth) acrylates include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, glycerin tri (meth) acrylate, and the like. .

  Examples of the tetra (meth) acrylates include ditrimethylolpropane tetra (meth) acrylate and pentaerythritol tetra (meth) acrylate.

  Examples of the polyfunctional vinyl ethers include trimethylolpropane trivinyl ether, ditrimethylolpropane tetravinyl ether, glycerin trivinyl ether, and the like.

  If necessary, the polymerization reaction may be a copolymerization of the polyfunctional polymerizable monomer and the monofunctional polymerizable monomer. By copolymerizing, the size of the network in the polymer can be adjusted.

  Monofunctional polymerizable monomers include monofunctional acrylic monomers such as monofunctional (meth) acrylamides and monofunctional (meth) acrylates, monofunctional vinyl ethers, monofunctional N-vinyl compounds, or monofunctional And monofunctional vinyl monomers such as vinyl compounds, monofunctional α, β-unsaturated compounds, and the like.

  Examples of the monofunctional (meth) acrylamides include 2-acetamidoacrylic acid, (meth) acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, N- (butoxymethyl) acrylamide, N-tert-butylacrylamide, and diacetone. Examples include acrylamide, N, N-dimethylacrylamide, N- [3- (dimethylamino) propyl] methacrylamide.

  Examples of the monofunctional (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, methoxyethyl (meth) acrylate, Examples include methoxy polyethylene glycol (meth) acrylate, (meth) acrylic acid, N, N-dimethylaminoethyl (meth) acrylate, (poly) ethylene glycol methacrylate, polypropylene glycol (meth) acrylate, and the like.

  Examples of the monofunctional vinyl ethers include methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, methoxyethyl vinyl ether, and methoxypolyethylene glycol vinyl ether.

  Examples of the monofunctional N-vinyl compounds include N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylformamide, N-vinylacetamide and the like.

  Examples of the monofunctional vinyl compounds include styrene, α-methylstyrene, vinyl acetate and the like.

  Examples of the monofunctional α, β-unsaturated compounds include maleic anhydride, maleic acid, dimethyl maleate, diethyl maleate, fumaric acid, dimethyl fumarate, diethyl fumarate, monomethyl fumarate, monoethyl fumarate, and itaconic anhydride. Examples thereof include acid, itaconic acid, dimethyl itaconate, methylene malonic acid, dimethyl methylene malonate, cinnamic acid, methyl cinnamate, crotonic acid, and methyl crotonic acid.

  Next, polyethylene polyamines will be described.

  In the present invention, these amine compounds play a role of adsorbing and desorbing carbon dioxide in the structure of the polymer.

In the present invention, specific examples of polyethylenepolyamines include diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and pentaethylenehexamine (PEHA).
Here, “TETA” refers to a compound in which four amino groups are linked linearly or branchedly via an ethylene chain, but in the present invention, it also has four amino groups, Also included are those having a piperazine ring structure. Specific compound names of TETA include, for example, 1,4,7,10-tetraazadecane, N, N-bis (2-aminoethyl) -1,2-ethanediamine, 1- [2-[( 2-aminoethyl) amino] ethyl] -piperazine, 1,4-bis (2-aminoethyl) -piperazine and the like.

  “TEPA” refers to a compound in which five amino groups are linked in a straight or branched chain via an ethylene chain, and in the present invention, it also has five amino groups, and Those having a piperazine ring structure are also included. Specific compound names of TEPA include, for example, 1,4,7,10,13-pentaazatridecane, N, N, N′-tris (2-aminoethyl) -1,2-ethanediamine, 1 -[2- [2- [2-[(2-aminoethyl) amino] ethyl] amino] ethyl] -piperazine, 1- [2- [bis (2-aminoethyl) amino] ethyl] -piperazine, bis [ 2- (1-piperazinyl) ethyl] amine and the like.

  “PEHA” refers to a compound in which six amino groups are linked in a straight chain or branched form through an ethylene chain, and in the present invention, it also has six amino groups, and Those having a piperazine ring structure are also included. Specific compound names of PEHA include, for example, 1,4,7,10,13,16-hexaazahexadecane, N, N, N ′, N′-tetrakis (2-aminoethyl) -1,2- Ethanediamine, N, N-bis (2-aminoethyl) -N ′-[2-[(2-aminoethyl) amino] ethyl] -1,2-ethanediamine, 1- [2- [2- [2 -[2- [2-[(2-aminoethyl) amino] ethyl] amino] ethyl] amino] ethyl] -piperazine, 1- [2- [2- [2- [bis (2-aminoethyl) amino] Ethyl] amino] ethyl] -piperazine, N, N′-bis [2- (1-piperazinyl) ethyl] -1,2-ethanediamine, and the like.

Among these, as polyethylenepolyamines, from the viewpoint of easy availability and acquisition cost,
Diethylenetriamine (DETA),
1,4,7,10-tetraazadecane, N, N-bis (2-aminoethyl) -1,2-ethanediamine, 1- [2-[(2-aminoethyl) amino] ethyl] -piperazine, And triethylenetetramine (TETA) consisting of a mixture of 1,4-bis (2-aminoethyl) -piperazine,
1,4,7,10,13-pentaazatridecane, N, N, N′-tris (2-aminoethyl) -1,2-ethanediamine, 1- [2- [2- [2-[( 2-aminoethyl) amino] ethyl] amino] ethyl] -piperazine, 1- [2- [bis (2-aminoethyl) amino] ethyl] -piperazine, and bis [2- (1-piperazinyl) ethyl] amine Tetraethylenepentamine (TEPA) composed of a mixture, and 1,4,7,10,13,16-hexaazahexadecane, N, N, N ′, N′-tetrakis (2-aminoethyl) -1,2- Ethanediamine, N, N-bis (2-aminoethyl) -N ′-[2-[(2-aminoethyl) amino] ethyl] -1,2-ethanediamine, 1- [2- [2- [2 -[2- [2-[(2-aminoethyl Amino] ethyl] amino] ethyl] amino] ethyl] -piperazine, 1- [2- [2- [2- [bis (2-aminoethyl) amino] ethyl] amino] ethyl] -piperazine, and N, N ′ Pentaethylenehexamine (PEHA) comprising a mixture of bis [2- (1-piperazinyl) ethyl] -1,2-ethanediamine
Particularly preferred is at least one selected from the group consisting of

  In the present invention, other raw materials may be used in combination with the amine compound of the present invention as long as it does not contradict the spirit of the present invention.

  In the present invention, polyethylene polyamines may be commercially available or may be synthesized by a known method, and are not particularly limited. The purity of the polyethylene polyamines is not particularly limited, but is preferably 95% or more, and particularly preferably 99% or more, considering the ease of purification in the purification step.

  The weight fraction of the high molecular polymer and polyethylene polyamines used in the present invention is not particularly limited. From the viewpoint of enhancing the separation ability of carbon dioxide and hydrogen, it is desirable that the weight fraction of the polyethylene polyamines is 2 to 80%, preferably 30 to 70%, more preferably 40 to 60%.

  The polymer membrane of the present invention can be used as a self-supporting membrane because the polyethylene polyamines do not leak out when pressure is applied, but it can be used as a composite membrane with a known supporting membrane. Is not particularly limited.

  Next, the manufacturing method of the high molecular polymer in this invention is demonstrated.

  The method for producing a polymer film of the present invention is characterized in that a polyfunctional polymerizable monomer is polymerized in the presence of at least one compound selected from the group consisting of polyethylene polyamines.

  In the present invention, the method for polymerizing the polyfunctional polymerizable monomer in the presence of at least one compound selected from the group consisting of polyethylene polyamines is not particularly limited, and photopolymerization is possible even in thermal polymerization. It may be. In this case, a polymerization initiator is usually used (heat or light).

  As the thermal polymerization initiator, known ones can be used. Specifically, methyl ethyl ketone peroxide, benzoyl peroxide, dicumyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, t-butyl peroxide Organic peroxides such as octoate, t-butylperoxybenzoate, and lauroyl peroxide; azo compounds such as azobisisobutyronitrile are suitable. In addition, a curing accelerator may be used by mixing at the time of thermal polymerization, and as the curing accelerator, cobalt naphthenate, cobalt octylate, etc., or tertiary amine is suitable. The amount of the thermal polymerization initiator added is preferably about 0.01 to 10 parts by weight, more preferably about 0.1 to 1 part by weight with respect to 100 parts by weight of the polyfunctional polymerizable monomer.

  As the photopolymerization initiator, known ones can be used, and specifically, the following compounds are suitable. These are used alone or as a mixture of two or more.

  Benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 4- (1 -T-butyldioxy-1-methylethyl) acetophenone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one and 2-benzyl-2-dimethylamino-1- (4 -Morpholinophenyl) -butanone-1, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2) -Pro Le) ketone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] acetophenone such as propanone oligomer.

  Anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone; 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2- (3-dimethylamino-2-hydroxy) -3,4-dimethyl-9H-thioxanthone Thioxanthones such as -9-one mesochloride; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenone, 4- (1-t-butyldioxy-1-methylethyl) benzofe 3,3 ′, 4,4′-tetrakis (t-butyldioxycarbonyl) benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4′-methyl-diphenyl sulfide, 3,3 ', 4,4'-tetra (t-butylperoxylcarbonyl) benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl-N, N-dimethyl-N- [2- (1-oxo-2-propenyl) Benzophenones such as (oxy) ethyl] benzenemethananium bromide and (4-benzoylbenzyl) trimethylammonium chloride; acylphosphine oxides and xanthones.

  The addition amount of the photopolymerization initiator is preferably about 0.5 to 10 parts by weight, more preferably about 2 to 3 parts by weight with respect to 100 parts by weight of the polyfunctional polymerizable monomer.

  When the polyfunctional polymerizable monomer used in the present invention is cured by light, a basic sensitizer can be used as a sensitizer together with a photopolymerization initiator. As the basic sensitizer, an amine sensitizer is preferably used, and the amine sensitizer is not particularly limited. Specifically, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, Examples include triethylamine, monopropylamine, dimethylpropylamine, monoethanolamine, diethanolamine, ethylenediamine, diethylenetriamine, dimethylaminoethyl methacrylate, and polyethyleneimine. Of these, tertiary amine sensitizers are particularly preferred.

  In addition to the above, the tertiary amine sensitizers include triethanolamine, triisopropanolamine, tributanolamine, methyldiethanolamine, methyldiisopropanolamine, methyldibutanolamine, ethyldiethanolamine, ethyldiisopropanolamine, and ethyldiethanol. Butanolamine, propyldiethanolamine, propyldiisopropanolamine, propyldibutanolamine, dimethylethanolamine, dimethylisopropanolamine, dimethylbutanolamine, diethylethanolamine, diethylisopropanolamine, diethylbutanolamine, dipropylethanolamine, dipropylisopropanolamine, Dipropylbutanolamine, dibutylethanolamine, dibutyli Propanolamine, di-butyl butanolamine, methyl ethyl ethanolamine, methyl ethyl isopropanolamine, methyl ethyl butanol amine, benzyl diethanolamine, N- phenyl-diethanolamine, tetraethanol ethylenediamine, tetramethylenediamine propanol ethylenediamine, and the like. In addition, ethylene glycol is added to these hydroxyl group-containing tertiary amine sensitizers to introduce polyethylene glycol chains, and hydroxyl group-containing tertiary amine sensitizers are monomers containing functional groups that are reactive with hydroxyl groups. Those obtained by adding a polymerizable double bond by addition, those obtained by introducing a tertiary amino group into a polymer or oligomer, and the like can also be used. These amine sensitizers can be used alone or in combination of two or more.

  The amount of the sensitizer used is preferably about 1 to 10 parts by weight, more preferably about 5 to 8 parts by weight with respect to 100 parts by weight of the photopolymerization initiator.

  The polymerization reaction is preferably carried out in an appropriate solvent by heating in the case of thermal polymerization and by irradiation with ultraviolet rays in the case of photopolymerization. The solvent is not particularly limited as long as it dissolves the amine compound or the polyethylene polyamines and the polyfunctional polymerizable monomer, but usually an alcohol (for example, methanol, ethanol, etc.) can be preferably used. Heating in the thermal polymerization is usually performed at about 40 to 90 ° C., preferably about 60 to 70 ° C., usually for about 2 to 24 hours, preferably about 5 to 10 hours. The ultraviolet irradiation of the polymerization is usually performed for about 30 seconds to 10 minutes, preferably about 1 to 3 minutes, using a wavelength of about 200 to 400 nm, preferably about 250 to 360 nm.

  Next, the carbon dioxide separation method in the present invention will be described.

  The carbon dioxide separation method of the present invention includes a step of bringing a mixed gas containing carbon dioxide into contact with the above-described polymer membrane of the present invention to selectively permeate carbon dioxide in the mixed gas. Features. That is, the separation method of the present invention includes a step of bringing a mixed gas containing carbon dioxide into contact with the polymer membrane obtained above to selectively permeate carbon dioxide in the mixed gas.

  In the separation method of the present invention, it is preferable to provide a pressure difference between the gas supply side and the gas permeation side of the separation membrane. This pressure difference is usually provided by reducing the pressure on the gas permeation side. Moreover, it is desirable to carry out this separation method under a temperature condition of usually 5 to 80 ° C., preferably room temperature to 50 ° C.

  The mixed gas applicable to the separation method of the present invention is not particularly limited as long as it is a mixed gas containing carbon dioxide. However, in order to improve the separation performance between carbon dioxide and other gases, the relative humidity of the mixed gas is set to 30. % Or more, preferably 60 to 100%.

  In the separation method of the present invention, additional steps other than those described above may be carried out. For example, a cooling step, a heating step, a washing step, an extraction step, an ultrasonic treatment step, a distillation step, other treatment steps with a chemical solution, and the like can be appropriately performed.

The separation method of the present invention can be applied to, for example, separating carbon dioxide (CO ₂ ) from combustion exhaust gas generated in a thermal power plant, a steel plant, a cement factory, and the like.

  Hereinafter, the present invention will be described with reference to examples, but the present invention should not be construed as being limited thereto.

[Example 1]
Diethylenetriamine (manufactured by Tosoh Corp.) 2 g as a polyethylene polyamine, and polyethylene glycol dimethacrylate (hereinafter abbreviated as “PEGDMA”, molecular weight: 750; Aldrich Corp.) 2 g (2.67 mmol) as methanol as a polyfunctional polymerizable monomer Dissolved in 2 g (Wako Pure Chemical Industries, Ltd.).

  Subsequently, 1-hydroxycyclohexyl phenyl ketone was added to 0.04 mmol / mL. The resulting solution was developed in a petri dish, and polyethylene glycol dimethacrylate was polymerized by irradiating with ultraviolet light (wavelength peak: 360 nm) at room temperature for 1 minute using a B-100AP lamp (manufactured by UVP). Thereafter, ethanol as a reaction solvent is distilled off under reduced pressure to obtain a target polymer membrane (hereinafter referred to as “product 1 of the present invention”). The film thickness of the present polymer film was about 0.02 mm, and the content of diethylenetriamine in the polymer film was 50% by weight.

[Example 2]
A target polymer membrane was obtained in the same manner as in Example 1 except that triethylenetetraamine (manufactured by Tosoh Corporation) was used as the polyethylene polyamines (hereinafter referred to as “product 2 of the present invention”). The film thickness of the polymer film was about 0.026 mm, and the content of triethylenetetraamine in the polymer film was 50% by weight.

[Example 3]
A target polymer film was obtained in the same manner as in Example 1 except that tetraethylenepentamine (manufactured by Tosoh Corp.) was used as the polyethylene polyamine (hereinafter referred to as “product 3 of the present invention”). The thickness of this polymer membrane was about 0.021 mm, and the content of tetraethylenepentamine in the polymer membrane was 50% by weight.

[Example 4]
A target polymer film was obtained in the same manner as in Example 1 except that pentaethylenehexamine (manufactured by Tosoh Corporation) was used as the polyethylene polyamine (hereinafter referred to as “product 4 of the present invention”). The film thickness of this polymer film was about 0.026 mm, and the content of pentaethylenehexamine in the polymer film was 50% by weight.

[Comparative Example 1]
A polymer film was obtained in the same manner as in Example 1 except that the amine compound and polyethylene polyamines were not added (hereinafter referred to as “comparative product”). The film thickness of the obtained polymer film was 0.13 mm.

[Examples 5 to 8 and Comparative Example 2] Separation test of carbon dioxide and coexisting gas Using the polymer membranes obtained in Examples 1 to 5 and Comparative Example 1 (products 1 to 4 of the present invention and comparative products) The carbon dioxide separation ability was measured. In the following description and mathematical formula, carbon dioxide is abbreviated as CO ₂ .

An outline of the apparatus is shown in FIG. That is, a mixed gas (carbon dioxide gas 10%, coexisting gas 90%) is supplied to the polymer membrane, and the permeation fluxes Q (CO ₂ ) and Q (coexisting gas) of the gas that has permeated the separation membrane (unit: GPU = 1 × 10 ⁻⁶ cm ₃ (STP) / (s · cm ₂ · cmHg)) under the following conditions using a gas chromatography and a flow meter, the permeability coefficient is calculated according to the following formula, The selectivity α (CO ₂ / coexisting gas) = Q (CO ₂ / Q coexisting gas) was calculated. The results are shown in Table 1. Note that methane gas was used as the coexisting gas.

(Where Q is the permeation flux, n is the gas volume, l is the film thickness, A is the membrane area, t is the time, Δp is the difference between the supply side partial pressure and the permeation side partial pressure. Represents each gas.)

(In the formula, α means the permeation flux, QCO ₂ means the permeation flux of carbon dioxide, and Q coexistence gas means the permeation flux of the coexistence gas.)
<Setting conditions of gas permeation measuring device>
Supply gas amount: about 100 mL / min,
Measurement temperature: 40 ° C.
Supply gas composition: carbon dioxide / coexisting gas = 10/90 (vol / vol)
Permeation side sweep gas: He (dry),
Relative humidity: 80%
Pressure: supply side: 155 kPa, permeation side: 105 kPa.

<Gas chromatography analysis conditions>
Supply side TCD detector GC7870A (manufactured by Agilent Technology)
Column HayeSep Q × 0.5m MS5A × 6 feet HayeSep Q × 6 feet MS5A × 6 feet Transmission side PDHID detector GC7870A (manufactured by Agilent Technology)
Column SHINCARBON × 4m HayeSep Q × 0.5m
He sweep gas amount: 10 mL / min.

In Table 1, the unit of QCO ₂ and Q coexisting gas is GPU (1 × 10 ⁻⁶ cm ³ (STP) / (s · cm ² · cmHg)).

  From the above results, it was confirmed that the polymer membrane of the present invention has an excellent gas separation ability.

1 CO ₂ gas cylinder 2 Coexisting gas cylinder 3 He gas cylinder 4 Flow rate controller 5 Humidifier 6 Pressure gauge 7 Dew point meter 8 Membrane cell 9 Thermostatic chamber 10 Dehumidification trap

Claims (14)

A polymer film comprising a polymer of a polyfunctional polymerizable monomer and at least one selected from the group consisting of polyethylene polyamines. The polyfunctional polymerizable monomer is at least one selected from the group consisting of polyfunctional (meth) acrylamides, polyfunctional (meth) acrylates, polyfunctional vinyl ethers, and divinylbenzene. 1. The polymer film according to 1. The polyfunctional polymerizable monomer is at least one selected from the group consisting of di (meth) acrylates, tri (meth) acrylates, and tetra (meth) acrylates. Polymer membrane. Polyfunctional polymerizable monomers are (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane di (meth) The polymer film according to claim 1, wherein the polymer film is at least one selected from the group consisting of acrylate and pentaerythritol di (meth) acrylate. The polymer of a polyfunctional polymerizable monomer is a polymer of a polyfunctional polymerizable monomer and a monofunctional polymerizable monomer, according to any one of claims 1 to 4, Molecular film. Monofunctional polymerizable monomers include monofunctional (meth) acrylamides, monofunctional (meth) acrylates, monofunctional vinyl ethers, monofunctional N-vinyl compounds, monofunctional vinyl compounds, and monofunctional α, β 6. The polymer film according to claim 5, wherein the polymer film is at least one selected from the group consisting of unsaturated compounds. Monofunctional polymerizable monomers are methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, methoxyethyl (meth) acrylate, methoxypolyethylene It is at least one selected from the group consisting of glycol (meth) acrylate, (meth) acrylic acid, N, N-dimethylaminoethyl (meth) acrylate, (poly) ethylene glycol methacrylate and polypropylene glycol (meth) acrylate. 6. The polymer film according to claim 5, wherein 6. The polymer film according to claim 5, wherein the polyfunctional polymerizable monomer is polyethylene glycol dimethacrylate, and the monofunctional polymerizable monomer is polyethylene glycol methacrylate. The polyethylene polyamine is at least one selected from the group consisting of diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and pentaethylenehexamine (PEHA). The polymer film according to any one of 1 to 9. A gas separation membrane comprising the polymer membrane according to any one of claims 1 to 9. A method for producing a polymer film, comprising polymerizing a polyfunctional polymerizable monomer in the presence of at least one compound selected from the group consisting of polyethylene polyamines. The method for producing a polymer film according to claim 11, further comprising using a monofunctional polymerizable monomer as the polymerization component. The method for producing a polymer film according to claim 11 or 12, wherein the polymerization reaction is a photopolymerization reaction or a thermal polymerization reaction. A carbon dioxide comprising a step of bringing a mixed gas containing carbon dioxide into contact with the polymer membrane according to any one of claims 1 to 9 and selectively permeating carbon dioxide in the mixed gas. Separation method.

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