Separation method

Abstract

To provide a novel method for separating fluorocarbon.SOLUTION: A method for separating, from a first mixture containing fluorocarbon A with carbon number n having one or more double bonds and fluorocarbon B with carbon number m having no double bonds, a second mixture in which the composition ratio of fluorocarbon A to fluorocarbon B is different from that of the first mixture, the separation being conducted by bringing the first mixture into contact with an adsorbent comprising a metal-organic framework.SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to a separation method.

Background Art

[0002] As a method for separating fluorocarbons, a method of distilling a mixture of fluorocarbons is known. Patent Document 1 describes that after mixing a mixture containing 2,3,3,3-tetrafluoropropene and hexafluoropropene with an extraction solvent to obtain an extraction mixture, the extraction mixture is distilled to obtain a distillate mainly composed of hexafluoropropene and a bottoms containing 2,3,3,3-tetrafluoropropene.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] It has been found that in the distillation method described in Patent Document 1, it is difficult to separate compounds with close boiling points or azeotropic compounds, and there may be a problem that fluorocarbons, for example, fluorocarbons with different presence or absence of double bonds, cannot be sufficiently separated.

[0005] The problem in the present disclosure is to provide a new method for separating fluorocarbons.

Means for Solving the Problems

[0006] The present disclosure includes the following aspects. [1] From a first mixture containing a fluorocarbon A having one or more double bonds and a carbon number of n and a fluorocarbon B having no double bonds and a carbon number of m, Separating a second mixture having a composition ratio of the fluorocarbon A and the fluorocarbon B different from that of the first mixture, The separation is carried out by bringing the first mixture into contact with an adsorbent containing a metal-organic framework, a method for separating fluorocarbons. [2] The contact between the first mixture and the adsorbent containing the metal-organic framework is carried out at a temperature of -10°C or higher and 80°C or lower, the separation method according to [1]. [3] n is 2 or more and 3 or less, the separation method according to [1] or [2]. [4] m is 1 or more and 3 or less, the separation method according to any one of [1] to [3]. [5] The fluorocarbon A contains R1234yf, the separation method according to any one of [1] to [4]. [6] The fluorocarbon B contains one or two or more selected from R134a, R143, R143a, R32, and R125, the separation method according to any one of [1] to [5]. [7] The metal-organic framework contains metal ions, the separation method according to any one of [1] to [6]. [8] The metal-organic framework contains one or two or more organic ligands, and the organic ligand contains two or more groups capable of coordinating to metal ions in one molecule, the separation method according to any one of [1] to [7]. [9] The metal-organic framework contains metal ions and one or two or more organic ligands, and the organic ligand contains two or more groups capable of coordinating to metal ions in one molecule, the separation method according to any one of [1] to [8].

[10] The metal-organic framework has an open metal site composed of coordinatively unsaturated metal ions, the separation method according to any one of [1] to [9].

[11] The adsorbent containing the metal-organic structure further contains a resin, and is the separation method according to any one of [1] to

[10] .

[12] The adsorbent containing the metal-organic structure is in powder form, granular form, flake form or pellet form, and is the separation method according to any one of [1] to

[11] .

[13] The first mixture is an azeotropic mixture or pseudo-azeotropic mixture of fluorocarbons, and is the separation method according to any one of [1] to

[12] .

[14] The separation method according to any one of [1] to

[13] , further comprising contacting the separated second mixture with the adsorbent containing the metal-organic structure.

[15] The separation method according to any one of [1] to

[14] , further comprising purifying the separated second mixture.

[16] After contacting the first mixture with the adsorbent containing the metal-organic structure, The separation method according to any one of [1] to

[15] , further comprising desorbing the fluorocarbon A adsorbed on the adsorbent containing the metal-organic structure from the adsorbent containing the metal-organic structure.

[17] A fluorocarbon purification system that implements the separation method according to any one of [1] to

[16] .

[18] From a first mixture containing a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and having no double bonds, Separating a third mixture in which the concentration of the fluorocarbon A is reduced compared to the first mixture, The separation is carried out by contacting the first mixture with an adsorbent, and is a method for separating fluorocarbons.

[19] The contact between the first mixture and the adsorbent is carried out at a temperature of -10°C or higher and 80°C or lower, and is the separation method according to

[18] .

[20] The n is 2 or more and 3 or less, and the separation method described in

[18] or

[19] .

[21] The m is 1 or more and 3 or less, and the separation method described in any one of

[18] to

[20] .

[22] The separation method according to any one of

[18] to

[21] , wherein the fluorocarbon A contains R1234yf.

[23] The separation method according to any one of

[18] to

[22] , wherein the fluorocarbon B contains one or more selected from R134a, R143, R143a, R32, and R125.

[24] The separation method according to any one of

[18] to

[23] , wherein the adsorbent contains a porous body.

[25] The separation method according to any one of

[18] to

[24] , wherein the adsorbent contains a metal-organic structure.

[26] The separation method according to

[25] , wherein the metal-organic structure contains metal ions.

[27] The separation method according to

[25] , wherein the metal-organic structure contains one or more organic ligands, and the organic ligand contains two or more groups capable of coordinating to metal ions in one molecule.

[28] The separation method according to

[25] , wherein the metal-organic structure contains metal ions and one or more organic ligands, and the organic ligand contains two or more groups capable of coordinating to metal ions in one molecule.

[29] The separation method according to

[25] , wherein the metal-organic structure has an open metal site composed of coordinatively unsaturated metal ions.

[30] The separation method according to any one of

[18] to

[29] , wherein the adsorbent further contains a resin.

[31] The separation method according to any one of

[18] to

[30] , wherein the adsorbent is in powder form, granular form, flake form, or pellet form.

[32] The separation method according to any one of

[18] to

[31] , wherein the first mixture is an azeotropic mixture or a pseudo-azeotropic mixture of fluorocarbons.

[33] The separation method according to any one of

[18] to

[32] , further comprising contacting the separated third mixture with an adsorbent.

[34] The separation method according to any one of

[18] to

[33] , further comprising purifying the separated third mixture.

[35] After contacting the first mixture with the adsorbent, The separation method according to any one of

[18] to

[34] , further comprising desorbing the fluorocarbon A adsorbed on the adsorbent from the adsorbent.

[36] A fluorocarbon purification system that implements the separation method according to any one of

[18] to

[35] .

[37] A composite material comprising a metal-organic framework and a fluorocarbon A having n carbon atoms and one or more double bonds, The metal-organic framework has an open metal site composed of a coordination-unsaturated metal ion.

Advantages of the Invention

[0007] According to the present disclosure, a new method for separating fluorocarbons can be provided.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0009] (First Embodiment: First Separation Method) The first separation method of the present disclosure is from a first mixture containing a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and having no double bonds, separating a second mixture in which the composition ratio of the fluorocarbon A and the fluorocarbon B is different from that of the first mixture, wherein the separation is carried out by bringing the first mixture into contact with an adsorbent containing a metal-organic framework.

[0010] According to the first separation method of the present disclosure, by bringing an adsorbent containing a metal-organic framework into contact with a first mixture containing two or more kinds of fluorocarbon gases, a second mixture in which the proportion of either the fluorocarbon gas having a double bond or the fluorocarbon gas having no double bond is reduced can be separated. The present disclosure should not be construed as being limited to a specific theory, but it is considered that the pore structure of the metal-organic framework can control the adsorption behavior between the fluorocarbon A having a double bond or the fluorocarbon B having no double bond and the metal-organic framework, and a mixture having a different composition ratio can be obtained. Note that the second mixture may include a case where it does not contain either the fluorocarbon A or the fluorocarbon B.

[0011] In one aspect, the first separation method is from a first mixture containing a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and having no double bonds, separating a second mixture in which the concentration of the fluorocarbon A is reduced from that of the first mixture, wherein the separation is carried out by bringing the first mixture into contact with an adsorbent containing a metal-organic framework.

[0012] In another aspect, the first separation method is from a first mixture containing a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and having no double bonds, separating a second mixture in which the concentration of the fluorocarbon B is reduced from the first mixture, wherein the separation is carried out by bringing the first mixture into contact with an adsorbent containing a metal-organic framework.

[0013] (First mixture) The first mixture includes a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and having no double bond. In the present embodiment, the fluorocarbon A or the fluorocarbon B is also referred to as an adsorbate.

[0014] In the fluorocarbon A, the number of double bonds is 1 or more, preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less, and still more preferably 1 or more and 2 or less.

[0015] The number of carbon atoms n of the fluorocarbon A is preferably 2 or more and 10 or less, more preferably 2 or more and 5 or less, and still more preferably 2 or more and 3 or less.

[0016] The boiling point of the fluorocarbon A may be, for example, -80 °C or higher and -20 °C or lower, and may further be -60 °C or higher and -30 °C or lower. In one aspect, in the first mixture, the fluorocarbon having n carbon atoms exists as a gas.

[0017] Examples of the fluorocarbon A include hydrochlorofluoroolfins and hydrofluoroolfins.

[0018] Examples of the hydrofluoroolfin include 1,1-difluoroethylene, 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene, hexafluoropropene, 1,1,1,4,4,4-hexafluorobutene, and the like. The fluorocarbon A is preferably a hydrofluorocarbon, and more preferably 2,3,3,3-tetrafluoropropene (R1234yf).

[0019] Examples of the hydrochlorofluorocarbon include 1-chloro-3,3,3-trifluoropropene, 1-chloro-2,3,3,3-tetrafluoropropene, and the like. The fluorocarbon A may contain one or more compounds.

[0020] The concentration of the fluorocarbon A in the first mixture may be, for example, 0.0001 mol% or more and 90 mol% or less, and further may be 0.0001 mol% or more and 20 mol% or less, in the whole of the first mixture.

[0021] The number of carbon atoms m of the fluorocarbon B is preferably 1 or more and 10 or less, more preferably 1 or more and 5 or less, and still more preferably 1 or more and 3 or less.

[0022] The difference between the number of carbon atoms of the fluorocarbon A and the number of carbon atoms of the fluorocarbon B may be, for example, 0 or more and 5 or less, further may be 0 or more and 3 or less, and particularly may be 0 or more and 1 or less. According to the separation method of the present disclosure, even when the number of carbon atoms of the fluorocarbon A and the fluorocarbon B are close, a second mixture having a different composition ratio can be separated.

[0023] The boiling point of the fluorocarbon B may be, for example, -80°C or more and -20°C or less, and further may be -60°C or more and -30°C or less. In one aspect, in the first mixture, the fluorocarbon having n carbon atoms exists as a gas.

[0024] The difference between the boiling point of the fluorocarbon A and the boiling point of the fluorocarbon B may be, for example, 0°C or more and 20°C or less, and further may be 0°C or more and 10°C or less. According to the separation method of the present disclosure, even when the boiling points of the fluorocarbon A and the fluorocarbon B are close, a second mixture having a different composition ratio can be separated.

[0025] Examples of the fluorocarbon B include hydrochlorofluorocarbons and hydrofluorocarbons.

[0026] Examples of the hydrofluorocarbon include difluoromethane, 1,1-difluoroethane, 1,2-difluoroethane, 1,1,1-trifluoroethane, 1,1,2-trifluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,2,2-tetrafluoroethane, pentafluoroethane, and the like.

[0027] Examples of the hydrochlorofluorocarbon include chlorodifluoromethane, chlorotrifluoroethane, and the like.

[0028] As the fluorocarbon B, a hydrofluorocarbon is preferable, and more preferably one or more selected from 1,1,1,2-tetrafluoroethane (R134a), 1,1,1-trifluoroethane (R143a), and 1,1,1,2,2-pentafluoroethane (R125). The fluorocarbon B may contain one or more compounds.

[0029] The concentration of the fluorocarbon B in the first mixture may be, for example, 0.0001 mol% or more and 90 mol% or less, and further may be 0.0001 mol% or more and 20 mol% or less in the whole of the first mixture.

[0030] When the composition ratio (A / (A + B)×100) of the fluorocarbon A and the fluorocarbon B in the first composition is C1, C1 may be, on a molar basis, for example, 0.0001 or more and 90 or less, more preferably 0.0001 or more and 50 or less, and still more preferably 0.0001 or more and 20 or less.

[0031] The first mixture described above may be an azeotropic mixture or a pseudo-azeotropic mixture of fluorocarbons. According to the separation method of the present disclosure, even if it is an azeotropic mixture or a pseudo-azeotropic mixture, fluorocarbons with a specific number of carbon atoms can be separated. Examples of such an azeotropic mixture or pseudo-azeotropic mixture include mixtures in which the difference between the boiling point of the fluorocarbon to be separated (in this embodiment, fluorocarbon A or fluorocarbon B) and the boiling point of other fluorocarbons is 1 °C or more and 20 °C or less, and further 3 °C or more and 18 °C or less at 1 atmosphere (1,013 hPa).

[0032] In one aspect, fluorocarbon A can be 2,3,3,3-tetrafluoropropene (R1234yf), and fluorocarbon B can be one or more selected from 1,1,1,2-tetrafluoroethane (R134a), 1,1,1-trifluoroethane (R143a), and 1,1,1,2,2-pentafluoroethane (R125).

[0033] The first mixture described above may contain other compounds in addition to fluorocarbon A and fluorocarbon B. The boiling point of such other compounds may be, for example, -100 °C or lower, and may be -150 °C or lower. In one aspect, such other compounds are contained in the first mixture as a gas (gas).

[0034] Examples of such other compounds include nitrogen, oxygen, carbon dioxide, water, and the like.

[0035] (Adsorbent) The adsorbent described above contains a metal-organic structure (PCP: Porous Coordination Polymer, or MOF: Metal-Organic Framework). Hereinafter, in this embodiment, the adsorbent containing a metal-organic structure is also simply referred to as an adsorbent.

[0036] The above metal-organic framework can typically be an organic-inorganic composite structure having a regularly continuous three-dimensional skeleton. The metal-organic framework preferably contains metal ions and one or more organic ligands. The organic ligand preferably contains two or more groups capable of coordinating to the metal ions in one molecule. By coordinating the organic ligand to the metal ions, a highly regular and three-dimensionally continuous structure (e.g., a network structure) is formed, and pores are formed between the metal ions and the organic ligand. In such a three-dimensional structure, by combining the types of metal ions and the organic ligand, the effective pore diameter, flexibility of the metal-organic framework, and the interaction between the metal-organic framework and the adsorbate can be controlled. In addition, the metal-organic framework does not show a decrease in the adsorption amount (maximum adsorption amount) even after repeated adsorption and desorption of the adsorbate, and has high repeated durability. Furthermore, the metal-organic framework is less affected by temperature (heat) and humidity, and even when stored at high temperature and high humidity for a long time, the adsorption amount does not decrease, and it has high high-temperature and high-humidity durability.

[0037] Due to the pore structure of the metal-organic framework, the adsorption behavior between the fluorocarbon A having a double bond or the fluorocarbon B having no double bond and the metal-organic framework can be controlled, and it is considered possible to change the composition ratio of the fluorocarbon A and the fluorocarbon B in the first mixture.

[0038] The above metal ions are not particularly limited. For example, they are ions of metals selected from the group consisting of Group Ia, Group IIa, Group IIIa, Groups IVa to VIII, and Groups Ib to VIb. Such metals are preferably one or more selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ro, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Hg, Al, Ga, In, TI, Si, Ge, Sn, Pb, As, Sb, Bi, La, Ce, Pr, Nd, Pm, Sm, En, Gd, Tb, Dy, Ho, Er, Tm, and Yb, and more preferably one or more selected from the group consisting of Zn, Cu, Ti, Co, Mn, Ni, Al, Ca, Zr, and Mg.

[0039] Specifically, such metal ions are Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Sc 3+ , Y 3+ , Ln 3+ , Ti 4+ , Zr 4+ , Hf 4+ , V 4+ , V 3+ , V 2+ , Nb 3+ , Ta 3+ , Cr 3+ , Mo 3+ , W 3+ , Mn 3+ , Mn 2+ , Re 3+ , Re 2+ , Fe 3+ , Fe 2+ , Ru 3+ , Ru 2+ , Os 3+ , Os 2+ , Co 3+ , Co 2+ , Rh 2+ , Rh + , Ir 2+ , Ir + , Ni 2+ , Ni + , Pd 2+ , Pd+ 、Pt 2+ 、Pt + 、Cu 2+ 、Cu + 、Ag + 、Au + 、Zn 2+ 、Cd 2+ 、Hg 2+ 、Al 3+ 、Ga 3+ 、ln 3+ 、TI 3+ 、Si 4+ 、Si 2+ 、Ge 4+ 、Ge 2+ 、Sn 4+ 、Sn 2+ 、Pb 4+ 、Pb 2+ 、As 5+ 、As 3+ 、As + 、Sb 5+ 、Sb 3+ 、Sb + 、Bi 5+ 、Bi 3+ 、Bi + 、La 3+ 、Ce 3+ 、Pr 3+ 、Nd 3+ 、Pm 3+ 、Sm 3+ 、En 3+ 、Gd 3+ 、Tb 3+ 、Dy 3+ 、Ho 3+ 、Er 3+ 、Tm 3+ and Yb 3+ may be one or more selected from the group consisting of, more preferably, Cr 3+ 、Zn 2+ 、Cu 2+ 、Cu+, Ti 4+ 、Ti 3+ 、Co 3+ 、Co 2+ 、Mn 3+ 、Mn 2+ 、Fe 3+ 、Fe 2+ 、Ni 2+ 、Ni + 、Al 3+ 、Ca 2+ 、Zr4+ and Mg 2+ may be one or more selected from the group consisting of.

[0040] The above metal ions may be only one kind or two or more kinds. Preferably, the above metal ions are one kind.

[0041] In a preferred embodiment, the above metal ions are one or more selected from Fe ions, Cu ions, Ni ions, Mg ions, Co ions, Cr ions, Zr ions and Zn ions, preferably Fe 2+ , Fe 3+ , Cu 2+ , Ni 2+ , Mg 2+ , Co 2+ , Cr 3+ and Zn 2+ are one or more selected from.

[0042] The above organic ligand is not particularly limited as long as it contains two or more groups capable of coordinating to metal ions in one molecule. The above coordination bond is formed, for example, by a functional group capable of forming a coordination bond with a metal ion.

[0043] Examples of the functional group capable of forming the coordination bond include, for example, -COOH, -CS2H, -NO2, -B(OH)2, -SO3H, -Si(OH)3, -Ge(OH)3, -Sn(OH)3, -Si(SH)4, -Ge(SH)4, -Sn(SH)3, -PO3H, -AsO3H, -AsO4H, -P(SH)3, -As(SH)3, -CH(RSH)2, -C(RSH)3, -CH(RNH2)2, -C(RNH2)3, -CH(ROH)2, -C(ROH)3, -CH(RCN)3, and -C(RCN)3. In the above formula, R is a single bond, an alkylene group having 1 to 5 carbon atoms (for example, methylene, ethylene, n-propylene, i-propylene, n-butylene, i-butylene, tert-butylene or n-pentylene group), a divalent aromatic group having 6 to 14 carbon atoms (for example, phenylene), or a combination of the above alkylene group and aromatic group (for example, -phenylene-alkylene-phenylene-). Further, the functional group capable of forming the coordination bond may be a hetero atom (for example, N, O, S, B, P, Si, Al) contained in a heterocyclic ring, and preferably may be a nitrogen atom contained in a heterocyclic ring.

[0044] In a preferred embodiment, the functional group capable of forming the coordination bond can be -COOH and a nitrogen atom contained in a heterocyclic ring, etc.

[0045] The above organic ligand preferably has the above functional group so as to be bidentate or more. In such an organic ligand, the portion other than the functional group is not limited as long as the organic ligand can form a coordination bond with a metal ion.

[0046] In one embodiment, the above organic ligand is derived from a saturated or unsaturated aliphatic compound or aromatic compound. Further, the above ligand may be derived from a compound in which such an aliphatic compound and an aromatic compound are bonded (hereinafter, also referred to as "aliphatic aromatic compound").

[0047] The aliphatic moiety of the above aliphatic compound or aliphatic aromatic compound may be linear, branched, or cyclic. When the aliphatic moiety is cyclic, it may have a plurality of rings. The aliphatic moiety of the above aliphatic compound or aliphatic aromatic compound preferably has 1 to 15 carbon atoms, more preferably 1 to 10 carbon atoms, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. In a preferred embodiment, the above aliphatic moiety is derived from methane, adamantane, acetylene, ethylene, or butadiene.

[0048] The aromatic moiety of the above aromatic compound or aromatic aliphatic compound may have one or more rings, for example, 2, 3, 4, or 5 rings. These rings may or may not be fused. The aromatic moiety of the above aromatic compound or aliphatic aromatic compound preferably has 1, 2, or 3 rings, more preferably 1 or 2 rings. Also, each ring of the above compound may have at least one heteroatom in the ring, for example, N, O, S, B, P, Si, Al, preferably N, O, or S. The aromatic moiety of the aromatic compound or aromatic aliphatic compound preferably contains 1 or 2 rings having 6 carbon atoms. When there are 2 aromatic moieties, these 2 rings may or may not be fused. In a preferred embodiment, such an aromatic moiety is derived from benzene, naphthalene, biphenyl, bipyridyl, or pyridyl.

[0049] In one embodiment, the above organic ligand is derived from a dicarboxylic acid, tricarboxylic acid, or tetracarboxylic acid.

[0050] Examples of the dicarboxylic acid include oxalic acid, succinic acid, tartaric acid, maleic acid, 1,4-butanedicarboxylic acid, 1,4-butenedicarboxylic acid, 4-oxopyran-2,6-dicarboxylic acid, 1,6-hexanedicarboxylic acid, decanedicarboxylic acid, 1,8-heptadecanedicarboxylic acid, 1,9-heptadecanedicarboxylic acid, heptadecanedicarboxylic acid, acetylenedicarboxylic acid, 1,2-benzenedicarboxylic acid, 1,3-benzenedicarboxylic acid, 2,3-pyridinedicarboxylic acid, pyridine-2,3-dicarboxylic acid, 1,3-butadiene-1,4-dicarboxylic acid, 1,4-benzenedicarboxylic acid, p-benzenedicarboxylic acid, imidazole-2,4-dicarboxylic acid, 2-methylquinoline-3,4-dicarboxylic acid, quinoline-2,4-dicarboxylic acid, quinoxaline-2,3-dicarboxylic acid, 6-chloroquinoxaline-2,3-dicarboxylic acid, 4,4'-diaminophenylmethane-3,3'-dicarboxylic acid, quinoline-3,4-dicarboxylic acid, 7-chloro-4-hydroxyquinoline-2,8-dicarboxylic acid, diimidodicarboxylic acid, pyridine-2,6-dicarboxylic acid, 2-methylimidazole-4,5-dicarboxylic acid, thiophene-3,4-dicarboxylic acid, 2-isopropylimidazole-4,5-dicarboxylic acid, tetrahydropyran-4,4-dicarboxylic acid, perylene-3,9-dicarboxylic acid, perylenedicarboxylic acid, pullulol E200-dicarboxylic acid, 3,6-dioxaoctanedicarboxylic acid, 3,5-cyclohexadiene-1,2-dicarboxylic acid, octanedicarboxylic acid, pentane-3,3-dicarboxylic acid, 4,4'-diamino-1,1'-biphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, benzidine-3,3'-dicarboxylic acid, 1,4-bis(phenylamino)benzene-2,5-dicarboxylic acid, 1,1'-binaphthyldicarboxylic acid, 7-chloro-8-methylquinoline-2,3-dicarboxylic acid, 1-anilino-anthraquinone-2,4'-dicarboxylic acid, polytetrahydrofuran 250-dicarboxylic acid, 1,4-bis(carboxymethyl)piperazine-2,3-dicarboxylic acid, 7-chloroquinoline-3,8-dicarboxylic acid, 1-(4-carboxy)phenyl-3-(4-chloro)phenylpyrazoline-4,5-dicarboxylic acid, 1,4,5,6,7,7 - Hexachloro - 5 - norbornene - 2,3 - dicarboxylic acid, phenylindanedicarboxylic acid, 1,3 - dibenzyl - 2 - oxoimidazolidine - 4,5 - dicarboxylic acid, 1,4 - cyclohexanedicarboxylic acid, naphthalene - 1,8 - dicarboxylic acid, 2 - benzoylbenzene - 1,3 - dicarboxylic acid, 1,3 - dibenzyl - 2 - oxoimidazolidene - 4,5 - cis - dicarboxylic acid, 2,2’ - bipyridine - 4,4’ - dicarboxylic acid, pyridine - 3,4 - dicarboxylic acid, 3,6,9 - trioxaundecanedicarboxylic acid, hydroxybenzophenonedicarboxylic acid, pullulan E300 - dicarboxylic acid, pullulan E400 - dicarboxylic acid, pullulan E600 - dicarboxylic acid, pyrazole - 3,4 - dicarboxylic acid, 2,3 - pyrazinedicarboxylic acid, 5,6 - dimethyl - 2,3 - pyrazinedicarboxylic acid, 4,4’ - diamino(diphenyl ether)diimidodicarboxylic acid, 4,4’ - diaminodiphenylmethane diimidodicarboxylic acid, 4,4’ - diamino(diphenyl sulfone)diimidodicarboxylic acid, 1,4 - naphthalenedicarboxylic acid, 2,6 - naphthalenedicarboxylic acid, 1,3 - adamantanedicarboxylic acid, 1,8 - naphthalenedicarboxylic acid, 2,3 - naphthalenedicarboxylic acid, 8 - methoxy - 2,3 - naphthalenedicarboxylic acid, 8 - nitro - 2,3 - naphthalenedicarboxylic acid, 8 - sulfo - 2,3 - naphthalenedicarboxylic acid, anthracene - 2,3 - dicarboxylic acid, 2’,3’ - diphenyl - p - terphenyl - 4,4” - dicarboxylic acid, (diphenyl ether) - 4,4’ - dicarboxylic acid, imidazole - 4,5 - dicarboxylic acid, 4(1H) - oxothiocoumarin - 2,8 - dicarboxylic acid, 5 - tert - butyl - 1,3 - benzenedicarboxylic acid, 7,8 - quinoline dicarboxylic acid, 4,5 - imidazoledicarboxylic acid, 4 - cyclohexene - 1,2 - dicarboxylic acid, hexatriacontanedicarboxylic acid, tetradecanedicarboxylic acid, 1,7 - heptanedicarboxylic acid, 5 - hydroxy - 1,3 - benzenedicarboxylic acid, 2,5 - dihydroxy - 1,4 - benzenedicarboxylic acid, pyrazine - 2,3 - dicarboxylic acid, furan - 2,5 - dicarboxylic acid, 1 - nonene - 6,9 - dicarboxylic acid, eicosanedicarboxylic acid, 4,4’ - dihydroxy - 3,3’ - biphenyldicarboxylic acid, 4,4'-Dihydroxydiphenylmethane-3,3'-dicarboxylic acid, 1-amino-4-methyl-9,10-dioxo-9,10-dihydroanthracene-2,3-dicarboxylic acid, 2,5-pyridinedicarboxylic acid, cyclohexene-2,3-dicarboxylic acid, 2,9-dichlorofluorbene-4,11-dicarboxylic acid, 7-chloro-3-methylquinoline-6,8-dicarboxylic acid, 2,4-dichlorobenzophenone-2',5'-dicarboxylic acid, 1,3-benzenedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 1-methylpyrrole-3,4-dicarboxylic acid, 1-benzyl-1H-pyrrole-3,4-dicarboxylic acid, anthraquinone-1,5-dicarboxylic acid, 3,5-pyrazoledicarboxylic acid, 2-nitrobenzene-1,4-dicarboxylic acid, heptane-1,7-dicarboxylic acid, cyclobutane-1,1-dicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 5,6-dehydronorbornane-2,3-dicarboxylic acid, 5-ethyl-2,3-pyridinedicarboxylic acid, and camphordicarboxylic acid are mentioned.,

[0051] Examples of the above tricarboxylic acids include 2-hydroxy-1,2,3-propanetricarboxylic acid, 7-chloro-2,3,8-quinolinetricarboxylic acid, 1,2,3-, 1,2,4-benzenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 2-phosphono-1,2,4-butanetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, 4,4',4''-(1,3,5-benzenetriyl)trisbenzoic acid, 1-hydroxy-1,2,3-propanetricarboxylic acid, 4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-f]quinoline-2,7,9-tricarboxylic acid, 5-acetyl-3-amino-6-methylbenzene-1,2,4-tricarboxylic acid, 3-amino-5-benzoyl-6-methylbenzene-1,2,4-tricarboxylic acid, 1,2,3-propanetricarboxylic acid, and aurintricarboxylic acid.

[0052] Examples of the above-mentioned tetracarboxylic acids include perylene tetracarboxylic acids such as 1,1-dioxide peryl[1,12-bcd]thiophene-3,4,9,10-tetracarboxylic acid, perylene-3,4,9,10-tetracarboxylic acid or (perylene-1,12-sulfone)-3,4,9,10-tetracarboxylic acid, butane tetracarboxylic acids such as 1,2,3,4-butanetetracarboxylic acid or meso-1,2,3,4-butanetetracarboxylic acid, decane-2,4,6,8-tetracarboxylic acid, 1,4,7,10,13,16-hexaoxacyclooctadecane-2,3,11,13-tetracarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid, 1,2,11,12-dodecanetetracarboxylic acid, 1,2,5,6-hexanetetracarboxylic acid, 1,2,7,8-octanetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 1,2,9,10-decanetetracarboxylic acid, benzophenone tetracarboxylic acid, 3,3’,4,4’-benzophenone tetracarboxylic acid, tetrahydrofuran tetracarboxylic acid, and cyclopentane tetracarboxylic acids such as cyclopentane-1,2,3,4-tetracarboxylic acid.

[0053] In one embodiment, the above-mentioned organic ligand is derived from a heterocyclic ring capable of forming a coordination bond with a ring heteroatom. Examples of such heterocyclic rings include the following heterocyclic rings. The heterocyclic ring may be unsubstituted or substituted.

[0054]

Chemical formula

[0055] In one embodiment, the organic ligand is derived from an azole such as diazole or triazole, preferably from triazole.

[0056] In a preferred embodiment, the above-mentioned organic ligand includes an organic ligand derived from a polycarboxylic acid and an organic ligand derived from an azole, preferably includes an organic ligand derived from an aromatic polycarboxylic acid.

[0057] In a preferred embodiment, the organic ligand is selected from 1,4-benzenedicarboxylic acid, 1,2-benzenedicarboxylic acid, maleic acid, 1,3,5-benzenetricarboxylic acid, 4,4’,4”-(1,3,5-benzenetriyl)trisbenzoic acid, 2,5-dihydroxy-1,4-benzenedicarboxylic acid, oxalic acid, 4,4’-dihydroxy-3,3’-biphenyldicarboxylic acid, 2-hydroxy-1,2,3-propanetricarboxylic acid, 4,4’-bipyridine, triazole, imidazole, 3,3’-bipyrazole, benzimidazole, and 3,5-pyridinedicarboxylic acid. In a more preferred embodiment, the organic ligand is selected from 1,4-benzenedicarboxylic acid, 4,4’-dihydroxy-3,3’-biphenyldicarboxylic acid, 2-hydroxy-1,2,3-propanetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, and 2,5-dihydroxy-1,4-benzenedicarboxylic acid.

[0058] The above organic ligand may be only one kind or two or more kinds.

[0059] In the present disclosure, “derived from a compound” includes not only the compound itself but also a form in which a part of such a compound is protonated or a completely protonated form.

[0060] Preferably, the metal-organic structure has an open metal site composed of a coordinatively unsaturated metal ion. The open metal site means a site where the metal contained in the metal-organic structure is in a coordinatively unsaturated state and any molecule can be coordinated. The presence or absence of the open metal site does not depend on the types of metal ions and organic ligands.

[0061] Examples of the metal-organic framework having an open metal site include HKUST-1, MIL-100(Fe), MIL-101(Cr), MOF-74(Ni), MOF-74(Mg), MOF-74(Co), MOF-74(Cu), Mg2(dobpdc), and UTSA-16(Zn).

[0062] The above metal-organic framework can be produced by bringing a metal ion into contact with an organic ligand. The contact between such a metal ion and an organic ligand may be carried out in the presence of a solvent. Examples of the solvent include water, ethanol, dimethylformamide, toluene, methanol, chlorobenzene, diethylformamide, dimethyl sulfoxide, water, hydrogen peroxide, methylamine, sodium hydroxide solution, N-methylpyrrolidone ether, acetonitrile, benzyl chloride, triethylamine, or ethylene glycol, or a mixture thereof.

[0063] The contact between the metal ion and the organic ligand may be carried out under pressure or under normal pressure. Further, the temperature at which such contact is carried out may be, for example, 10 to 200°C, or may be 10 to 150°C. Further, stirring may be carried out when such contact is carried out.

[0064] The above effective pore diameter is, for example, 0.30 nm or more and 5.00 nm or less, preferably 0.4 nm or more and 4.00 nm or less, more preferably 1.00 nm or more and 2.50 nm or less. In one embodiment, the effective pore diameter of the above porous body is, for example, 0.30 nm or more, preferably 0.4 nm or more, more preferably 1.00 nm or more, and for example, 5.00 nm or less, preferably 4.00 nm or less, more preferably 2.00 nm or less.

[0065] The above-mentioned effective pore diameter is the pore diameter of a porous body such as a metal-organic framework determined from the degree of adsorption and the molecular diameter of an adsorbate when the porous body and the adsorbate are brought into contact with each other. Specifically, it can be obtained by using the Horvath-Kawazoe method to convert the relative pressure of the nitrogen adsorption isotherm into the effective pore diameter. As the conversion formula, the calculation formula described in J.Chem.Eng.Jpn., 1983, 16, 6, 470-475 may be used, and as the parameter values in the conversion formula, values based on the combination of carbon and nitrogen may be used.

[0066] The specific surface area of the above-mentioned metal-organic framework is, for example, 40 m 2 / g or more, preferably 100 m 2 / g or more, more preferably 300 m 2 / g or more, and may be, for example, 3,000 m 2 / g or less, and may be 2,000 m 2 / g or less. The specific surface area of the above-mentioned metal-organic framework is calculated from the adsorption isotherm of nitrogen gas using the BET method.

[0067] The equilibrium adsorption amount of fluorocarbon A or fluorocarbon B in the above-mentioned metal-organic framework, when measured in the range of a temperature of 298 K and a pressure of 0.4 PaG to 1 MPaG (gauge pressure), may be, for example, 1 g / 10 g or more and may be 100 g / 10 g or less.

[0068] The content rate of the metal-organic framework in the above-mentioned adsorbent is, for example, 50% by mass or more and 100% by mass or less, preferably 70% by mass or more and 100% by mass or less, and more preferably 90% by mass or more and 100% by mass or less.

[0069] The above-mentioned adsorbent may contain a resin in addition to the above-mentioned metal-organic framework. Examples of such resins include acrylic resins, polyurethane resins, polyolefin resins, polyester resins, polyamide resins, vinyl chloride resins, styrene resins, vinyl ether resins, polyvinyl alcohol resins, polycarbonate resins, and polysulfone resins.

[0070] The adsorbent may contain additives such as emulsifiers, defoamers, surfactants, leveling agents, thickeners, viscoelasticity modifiers, defoamers, wetting agents, dispersants, preservatives, plasticizers, penetrants, fragrances, bactericides, acaricides, fungicides, ultraviolet absorbers, antioxidants, antistatic agents, flame retardants, dyes, and pigments. Further, the adsorbent may be in the form of powder, granules, flakes, or pellets.

[0071] (Contact between the first mixture and the adsorbent) By bringing the first mixture into contact with the adsorbent, fluorocarbon A or fluorocarbon B can be adsorbed onto the metal-organic framework contained in the adsorbent, and a second mixture having a composition ratio of the fluorocarbon A and the fluorocarbon B different from that of the first mixture can be separated from the first mixture. In one aspect, when the first mixture is brought into contact with the adsorbent, it is preferable that the first mixture be brought into contact as a gas.

[0072] The contact between the first mixture and the adsorbent may be carried out, for example, by a batch method or a column method. The batch method is a method of bringing the adsorbent and the first mixture into contact by placing them in a sealable container and allowing them to stand for a certain period of time under conditions of a predetermined temperature and a predetermined pressure. The column method is a method of bringing the adsorbent and the first mixture into contact by filling the adsorbent into a container (column) and flowing the first mixture into the container (column).

[0073] In one aspect, the temperature during the contact may be, for example, 0°C or higher and 100°C or lower, and may further be 0°C or higher and 50°C or lower. In another aspect, the temperature during the contact may be, for example, 10°C or higher and 50°C or lower, 15°C or higher and 50°C or lower, or 15°C or higher and 30°C or lower. Also, the pressure (gauge pressure) during the contact may be 0 MPaG or higher and 2 MPaG or lower, or 0.2 MPaG or higher and 1.5 MPaG or lower. When the pressure during the contact is within the above range, the adsorbate is likely to be adsorbed by the adsorbent, the separation efficiency can be improved, and the pore structure of the adsorbent can be maintained.

[0074] When the above contact is carried out by the column method, the linear velocity of the above first mixture may be 0.01 cm / second or more and 100 cm / second or less, and may be 0.05 cm / second or more and 10 cm / second or less.

[0075] (Second mixture) The above second mixture contains one or more selected from the above fluorocarbon A and the above fluorocarbon B, and the composition ratio of fluorocarbon A and fluorocarbon B is different from that of the above first mixture. The above second mixture preferably contains the above fluorocarbon A and the above fluorocarbon B.

[0076] When the composition ratio (A / (A + B)×100) of fluorocarbon A and fluorocarbon B in the above second mixture is C2, C2 can be, for example, 0.0001 or more and 10 or less, more preferably 0.0001 or more and 5 or less, and even more preferably 0.0001 or more and 1 or less on a molar basis.

[0077] The molar concentration C of fluorocarbon A in the above second mixture A2 may be, for example, 0.0001 mol% or more and 1 mol% or less in the whole of the second mixture, and may further be 0.0001 mol% or more and 0.01 mol% or less.

[0078] (Regeneration of adsorbent) The separation method of the present disclosure may further include desorbing fluorocarbon A or fluorocarbon B adsorbed on the adsorbent from the adsorbent after bringing the above first mixture into contact with the above adsorbent. By desorbing the adsorbed fluorocarbon A or fluorocarbon B from the adsorbent, the adsorption capacity can be restored and the adsorbent can be regenerated. Also, thereby, fluorocarbon A or fluorocarbon B can be recovered.

[0079] In one aspect, the fluorocarbon desorbed from the adsorbent may be fluorocarbon A. In another aspect, the fluorocarbon desorbed from the adsorbent may be fluorocarbon B.

[0080] The elimination of the above-mentioned fluorocarbon A or fluorocarbon B can be carried out by reduced pressure, elevated temperature, the flow of air and nitrogen, or the flow of heated air and heated nitrogen, etc.

[0081] The pressure (gauge pressure) during the above-mentioned elimination can preferably be 0.1 MPaG or less, more preferably 0 MPaG or less, and even more preferably -0.10 MPaG or less. Also, the temperature during the above-mentioned elimination can preferably be 15 to 200 °C, more preferably 50 to 180 °C, and even more preferably 100 to 150 °C.

[0082] (Contact between the second mixture and the adsorbent) The separation method of the present disclosure may further include bringing the above-separated second mixture into contact with the above adsorbent. By such an operation, a new mixture having a composition ratio of fluorocarbon A and fluorocarbon B different from that of the second mixture can be obtained. In one aspect, when the concentration of fluorocarbon A in the second mixture is reduced compared to the concentration of fluorocarbon A in the first mixture, the concentration of fluorocarbon A in the new mixture is preferably reduced compared to the concentration of fluorocarbon A in the second mixture. In another aspect, when the concentration of fluorocarbon B in the second mixture is reduced compared to the concentration of fluorocarbon B in the first mixture, the concentration of fluorocarbon B in the new mixture is preferably reduced compared to the concentration of fluorocarbon B in the second mixture.

[0083] The number of contacts between the adsorbent and the mixture is not particularly limited, and may preferably be 1 to 5 times, more preferably 1 to 3 times. In the present disclosure, the first contact corresponds to the contact between the first mixture and the adsorbent, and the m-th contact of the adsorbent corresponds to the contact between the mixture obtained by the (m - 1)-th contact of the adsorbent and the adsorbent (where m is an integer of 2 or more). In the present embodiment, the adsorbent used in the second and subsequent contacts is an adsorbent containing a metal-organic framework, but is not limited thereto, and may be an adsorbent containing a porous body described in the second embodiment. Further, in two or more contacts, the adsorbents used may be the same as or different from each other.

[0084] The operation and conditions for bringing the mixture obtained by the (m - 1)-th contact into contact with the adsorbent can be carried out in the same manner as the operation and conditions for bringing the first mixture into contact with the adsorbent.

[0085] (Purification) The separation method of the present disclosure may further include purifying the separated second mixture. Such purification may include obtaining a new mixture in which the composition ratio of fluorocarbon A and fluorocarbon B is different from that of the second mixture. In one aspect, when the concentration of fluorocarbon A in the second mixture is reduced compared to the concentration of fluorocarbon A in the first mixture, the concentration of fluorocarbon A in the new mixture is preferably reduced compared to the concentration of fluorocarbon A in the second mixture. In another aspect, when the concentration of fluorocarbon B in the second mixture is reduced compared to the concentration of fluorocarbon B in the first mixture, the concentration of fluorocarbon B in the new mixture is preferably reduced compared to the concentration of fluorocarbon B in the second mixture.

[0086] The number of purification times is not particularly limited, and may preferably be 1 to 5 times, more preferably 1 to 3 times. In the present disclosure, the n-th purification means an operation of purifying the (n - 1)-th new mixture obtained by the (n - 1) purifications (where n is an integer of 2 or more).

[0087] In one aspect, the purification can be carried out by distillation or rectification. Such distillation may be carried out using a commonly used distillation column, for example, a packed column or a tray column. From the top of the distillation column, the purified product is distilled out as the distillate, and the remainder is distilled out as the bottoms from the bottom of the distillation column. The number of theoretical plates of the distillation column may be, for example, 1 to 100 plates. The pressure (gauge pressure) during distillation or rectification may be 0 MPaG or more and 5 MPaG or less. Also, the temperature at the top of the distillation column may be, for example, -60°C or more and 100°C or less, and the temperature at the bottom of the distillation column may be, for example, 50°C or more and 200°C or less. An extraction solvent may be allowed to coexist during distillation.

[0088] Rectification can be carried out by performing an operation of distilling the distillate again (an operation of performing distillation two or more times).

[0089] In this embodiment, the second mixture is being purified, but the present disclosure is not limited thereto. For example, the first mixture may be purified before contacting the first mixture with an adsorbent containing a metal-organic framework. That is, the mixture purified by the above operation may be contacted with an adsorbent containing a metal-organic framework.

[0090] (System) A fluorocarbon purification system (hereinafter, also simply referred to as "system") that performs the above first separation method is also included in the technical scope of the present disclosure.

[0091] The above system preferably includes an adsorbent containing a metal-organic framework, The adsorbent containing the metal-organic framework is from a first mixture containing a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and not having a double bond, and can separate a second mixture in which the composition ratio of the fluorocarbon A and the fluorocarbon B is different from that of the first mixture.

[0092] FIG. 1 schematically shows and describes an example of the system in this embodiment, a two-stage system.

[0093] In the system of FIG. 1, the first mixture is stored in the gas tank 1. The first mixture is supplied to the first-stage separation module 4a through the pressure regulator 2a and the mass flow controller 3a. In one aspect, the back pressure of the first mixture supplied to the separation module 4a can be pressurized and controlled by the pressure regulator 2a, but is not limited to such an aspect. The pressure regulator 2a can also be omitted.

[0094] The separation module 4a includes an adsorbent 10a containing a metal-organic framework, and the first mixture is supplied to the adsorbent 10a containing such a metal-organic framework.

[0095] In the two-stage separation device, after contacting the adsorbent 10a containing the metal-organic framework, the flow rate of the second mixture is measured by the mass flow meter 5, and is supplied to the second-stage separation module 4b through the pressure regulator 2b and the mass flow controller 3b. In one aspect, the back pressure of the second mixture supplied to the second-stage separation module 4b can be pressurized and controlled by the pressure regulator 2b, but is not limited to such an aspect. The pressure regulator 2b can also be omitted.

[0096] The second-stage separation module 4b includes an adsorbent 10b containing a metal-organic framework, and the second mixture is supplied to the adsorbent 10b containing such a metal-organic framework.

[0097] The new mixture separated by the contact between the second mixture and the adsorbent 10b containing the metal-organic framework is analyzed for its gas composition by the gas composition analyzer 8b through the pressure regulator 2c, and then recovered into the recovery pipe 9. In one aspect, a mass flow meter can be used to measure the flow rate of the new mixture separated by contacting the adsorbent 10b containing the metal-organic framework. Also, in one aspect, the gas composition analyzer 8a can be omitted.

[0098] In this embodiment, a two-stage separation device has been described, but the present invention is not limited thereto, and appropriate modifications can be made. For example, a one-stage, three-stage, or four-stage or higher separation device may be used.

[0099] In the case of a p-stage (p is 3 or more), in the separation module of the (p-1)-th stage, the (p-1)-th mixture separated by contact with the adsorbent is supplied to the separation module through a pressure regulator and a mass flow controller, and is brought into contact with the adsorbent contained in the separation module to further separate a new p-th mixture. After gas composition analysis that may be performed as necessary, the p-th mixture is recovered to perform the separation of the p-th stage.

[0100] (Composite material) A composite material containing a metal-organic framework and the above fluorocarbon A or the above fluorocarbon B is also included in the technical scope of the present disclosure. In such a composite material, the metal-organic framework preferably has an Open Metal Site. In one aspect, the composite material preferably contains a metal-organic framework and the above fluorocarbon A. In another aspect, the composite material preferably contains a metal-organic framework and the above fluorocarbon B.

[0101] In the above composite material, the content of fluorocarbon A or fluorocarbon B is, for example, 0.1 part by mass or more and 100 parts by mass or less, preferably 1 part by mass or more and 50 parts by mass or less, based on 100 parts by mass of the metal-organic framework.

[0102] In addition to the above fluorocarbon and porous organic salt, the above composite material may contain a resin. Examples of such resins include acrylic resins, polyurethane resins, polyolefin resins, polyester resins, polyamide resins, vinyl chloride resins, styrene resins, vinyl ether resins, polyvinyl alcohol resins, polycarbonate resins, and polysulfone resins.

[0103] The above composite material may contain additives such as emulsifiers, defoamers, surfactants, leveling agents, thickeners, viscoelasticity modifiers, defoamers, wetting agents, dispersants, preservatives, plasticizers, penetrants, fragrances, bactericides, acaricides, fungicides, ultraviolet absorbers, antioxidants, antistatic agents, flame retardants, dyes, pigments, etc.

[0104] (Second Embodiment: Second Separation Method) The second separation method of the present disclosure is from a first mixture containing a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and having no double bonds, separating a third mixture in which the concentration of the fluorocarbon A is reduced compared to the first mixture, wherein the separation is carried out by bringing the first mixture into contact with an adsorbent.

[0105] According to the first separation method of the present disclosure, by bringing an adsorbent into contact with a first mixture containing two or more kinds of fluorocarbon gases, a third mixture in which the proportion of the fluorocarbon gas having a double bond is reduced can be separated. The present disclosure should not be construed as being limited to a specific theory, but it is considered that the fluorocarbon A having a double bond can be adsorbed by the adsorbent, and a third mixture in which the fluorocarbon A having a double bond is reduced can be obtained. Note that the above third mixture may include a case where it does not contain fluorocarbon A.

[0106] The above first mixture, fluorocarbon A and fluorocarbon B have the same meanings as the first mixture, fluorocarbon A and fluorocarbon B in the first embodiment.

[0107] The number of carbon atoms n of the above fluorocarbon A is preferably 2 or more and 10 or less, more preferably 2 or more and 5 or less, and still more preferably 2 or more and 3 or less.

[0108] As the above fluorocarbon A, hydrofluoroolefin is preferable, and 2,3,3,3 - tetrafluoropropene (R1234yf) is more preferable. The above fluorocarbon A may contain one or more compounds.

[0109] The concentration C of fluorocarbon A in the above first mixture A1 may be, for example, 0.0001 mol% or more and 90 mol% or less, and further may be 0.0001 mol% or more and 20 mol% or less, in the whole of the first mixture.

[0110] As the above fluorocarbon B, hydrofluorocarbons are preferable, and one or more selected from 1,1,1,2-tetrafluoroethane (R134a), 1,1,1-trifluoroethane (R143a), and 1,1,1,2,2-pentafluoroethane (R125) are more preferable. The above fluorocarbon B may contain one or more compounds.

[0111] The concentration of fluorocarbon B in the above first mixture may be, for example, 0.0001 mol% or more and 90 mol% or less, and further may be 0.0001 mol% or more and 20 mol% or less, in the whole of the first mixture.

[0112] The above first mixture may contain other compounds in addition to fluorocarbon A and fluorocarbon B. The boiling point of such other compounds may be, for example, -100 °C or lower, and may be -150 °C or lower. In one aspect, such other compounds are contained in the above first mixture as a gas.

[0113] Examples of such other compounds include nitrogen, oxygen, carbon dioxide, water, and the like.

[0114] (Adsorbent) The above adsorbent (hereinafter, also referred to as "second adsorbent" in the present embodiment) can adsorb a fluorocarbon A having n carbon atoms and a double bond. Typically, the second adsorbent adsorbs a fluorocarbon A having a double bond and does not adsorb a fluorocarbon B having no double bond. Therefore, by bringing the first mixture into contact with the second adsorbent, a third mixture with reduced fluorocarbon A can be separated from the first mixture.

[0115] The above second adsorbent preferably contains a porous body having pores as an adsorption medium. By adsorbing a fluorocarbon having n carbon atoms in such pores, the fluorocarbon having n carbon atoms can be separated from the first mixture.

[0116] The effective pore diameter of the porous body is, for example, 0.30 nm or more and 5.00 nm or less, preferably 0.4 nm or more and 4.00 nm or less, more preferably 1.00 nm or more and 2.50 nm or less. In one aspect, the effective pore diameter of the porous body is, for example, 0.30 nm or more, preferably 0.40 nm or more, more preferably 1.00 nm or more, and for example, 5.00 nm or less, preferably 4.00 nm or less, more preferably 2.00 nm or less.

[0117] The specific surface area of the porous body is, for example, 40 m 2 / g or more, preferably 100 m 2 / g or more, more preferably 300 m 2 / g or more, and can be, for example, 3,000 m 2 / g or less, and may be 2,000 m 2 / g or less. The specific surface area of the porous body is calculated using the BET method from the nitrogen gas adsorption isotherm.

[0118] The equilibrium adsorption amount of the fluorocarbon having n carbon atoms in the porous body, when measured in the range of a temperature of 298 K and a pressure of 0.4 PaG to 1 MPaG (gauge pressure), can be, for example, 1 g / 10 g or more and 100 g / 10 g or less.

[0119] The above-mentioned porous body may be in the form of powder (particles), film, granules, molded body (pellet, etc.), etc., and is preferably a molded body, and more preferably a pellet. The pellet may be cylindrical or spherical. In the case of a cylindrical shape, the radius of the cylinder is preferably 1.6 mm or more and 6 mm or less, and the thickness of the cylinder is preferably 2 mm or more and 6 mm or less. In the case of a spherical shape, it includes those that are not true spheres, and the radius of the sphere is preferably 4 mm or more and 12 mm or less.

[0120] The above-mentioned porous body preferably contains at least one selected from the group consisting of, for example, zeolite, activated carbon, silica gel, and metal-organic structures (PCP: Porous Coordination Polymer, or MOF: Metal-Organic Framework), and typically includes a metal-organic structure.

[0121] The above-mentioned metal-organic structure has the same meaning as the metal-organic structure in the first embodiment.

[0122] The content rate of the porous body in the above-mentioned second adsorbent is, for example, 50% by mass or more and 100% by mass or less, preferably 70% by mass or more and 100% by mass or less, and more preferably 90% by mass or more and 100% by mass or less.

[0123] The second adsorbent may contain a resin in addition to the above-mentioned porous body. Examples of such resins include acrylic resin, polyurethane resin, polyolefin resin, polyester resin, polyamide resin, vinyl chloride resin, styrene resin, vinyl ether resin, polyvinyl alcohol resin, polycarbonate resin, and polysulfone resin.

[0124] The above-mentioned second adsorbent may contain additives such as emulsifiers, defoamers, surfactants, leveling agents, thickeners, viscoelasticity modifiers, defoamers, wetting agents, dispersants, preservatives, plasticizers, penetrants, fragrances, bactericides, acaricides, fungicides, ultraviolet absorbers, antioxidants, antistatic agents, flame retardants, dyes, and pigments. Further, the second adsorbent may be in the form of powder, granules, flakes, or pellets.

[0125] (Contact between the first mixture and the second adsorbent) By bringing the first mixture into contact with the second adsorbent, fluorocarbon A contained in the first mixture can be adsorbed onto the adsorbent, and a third mixture with a reduced concentration of fluorocarbon A can be separated from the first mixture. In one embodiment, when bringing the first mixture into contact with the second adsorbent, it is preferable to bring the first mixture into contact as a gas.

[0126] The contact between the first mixture and the second adsorbent may be carried out, for example, by a batch method or a column method. The batch method is a method of bringing the first mixture into contact with the second adsorbent by placing the second adsorbent and the first mixture in a sealable container and allowing them to stand for a certain period of time under conditions of a predetermined temperature and a predetermined pressure. The column method is a method of bringing the first mixture into contact with the second adsorbent by filling the second adsorbent into a container (column) and flowing the first mixture into the container (column).

[0127] In one embodiment, the temperature during the contact may be, for example, 0°C or higher and 100°C or lower, and may further be 0°C or higher and 50°C or lower. In another embodiment, the temperature during the contact may be, for example, 10°C or higher and 50°C or lower, may be 15°C or higher and 50°C or lower, and may be 15°C or higher and 30°C or lower. Also, the pressure (gauge pressure) during the contact may be 0 MPaG or higher and 2 MPaG or lower, and may be 0.2 MPaG or higher and 1.5 MPaG or lower. When the pressure during the contact is within the above range, the adsorbate is likely to be adsorbed onto the adsorbent, the separation efficiency can be improved, and the pore structure of the adsorbent can be maintained.

[0128] When the contact is carried out by the column method, the linear velocity of the first mixture may be 0.01 cm / second or higher and 100 cm / second or lower, and may be 0.05 cm / second or higher and 10 cm / second or lower.

[0129] (The third mixture) The above-mentioned third mixture contains at least the above-mentioned fluorocarbon B, and the concentration of fluorocarbon A is reduced compared to the above-mentioned first mixture. The above-mentioned third mixture preferably contains fluorocarbon A and the above-mentioned fluorocarbon B.

[0130] When the composition ratio (A / (A + B)×100) of fluorocarbon A and fluorocarbon B in the above-mentioned third mixture is C3, C3 can be, for example, 0.0001 or more and 10 or less, more preferably 0.0001 or more and 5 or less, still more preferably 0.0001 or more and 1 or less on a molar basis.

[0131] The molar concentration C of fluorocarbon A in the above-mentioned third mixture A3 may be, for example, 0.0001 mol% or more and 1 mol% or less in the whole of the third mixture, and may further be 0.0001 mol% or more and 0.01 mol% or less.

[0132] (Regeneration of adsorbent) The separation method of the present disclosure may further include desorbing fluorocarbon A adsorbed on the above-mentioned second adsorbent from the above-mentioned second adsorbent after bringing the above-mentioned first mixture into contact with the above-mentioned second adsorbent. By desorbing the adsorbed fluorocarbon A from the above-mentioned second adsorbent, the adsorption capacity can be restored and the second adsorbent can be regenerated. Also, thereby, fluorocarbon A can be recovered. The desorption of the above-mentioned fluorocarbon A can be carried out by reduced pressure, temperature increase, flow of air and nitrogen, or flow of heated air and heated nitrogen, etc.

[0133] The pressure (gauge pressure) during the above-mentioned desorption may preferably be 0.1 MPaG or less, more preferably 0 MPaG or less, still more preferably -0.1 MPaG or less. Also, the temperature during the above-mentioned desorption may preferably be 15 to 200 °C, more preferably 50 to 180 °C, still more preferably 100 to 150 °C.

[0134] (Contact between the third mixture and the second adsorbent) The separation method of the present disclosure may further include contacting the separated third mixture with the second adsorbent. By such an operation, a new mixture with an even lower concentration of fluorocarbon A can be obtained.

[0135] The number of times of contact between the second adsorbent and the mixture is not particularly limited, and may preferably be 1 to 5 times, more preferably 1 to 3 times. In the case of contact two or more times, the second adsorbents used may be the same or different from each other.

[0136] The operation and conditions for contacting the mixture obtained by the (m - 1)-th contact with the adsorbent can be carried out in the same manner as the operation and conditions for contacting the first mixture with the adsorbent.

[0137] (Purification) The separation method of the present disclosure may further include purifying the separated third mixture. Such purification may include obtaining a new mixture in which the concentration of fluorocarbon A is further reduced than that of the second mixture.

[0138] The number of times of purification is not particularly limited, and may preferably be 1 to 5 times, more preferably 1 to 3 times. In the present disclosure, the n-th purification means an operation of purifying the (n - 1)-th new mixture obtained by the (n - 1)-th purification (where n is an integer of 2 or more).

[0139] In one aspect, the above purification can be carried out by distillation or rectification. Such distillation may be carried out using a generally used distillation column, for example, a packed column or a tray column. From the top of the distillation column, the purified product is distilled out as a distillate, and the remainder is distilled out as a bottoms from the bottom of the distillation column. The number of theoretical plates of the distillation column may be, for example, 1 to 100 plates. The pressure (gauge pressure) during distillation or rectification may be 0 MPaG or more and 5 MPaG or less. Also, the temperature at the top of the distillation column may be, for example, -60°C or more and 100°C or less, and the temperature at the bottom of the distillation column may be, for example, 50°C or more and 200°C or less. An extraction solvent may be allowed to coexist during distillation.

[0140] By performing the operation of distilling the above residue again (the operation of performing distillation two or more times), rectification can be carried out.

[0141] In this embodiment, the third mixture is being purified, but the present disclosure is not limited thereto. For example, the first mixture may be purified before contacting the adsorbent. That is, the mixture purified by the above operation may be contacted with the adsorbent.

[0142] (System) A fluorocarbon purification system that implements the above second separation method is also included in the technical scope of the present disclosure.

[0143] The above system preferably comprises an adsorbent, The above adsorbent is from a first mixture containing a fluorocarbon A having n carbon atoms and having one or more double bonds and a fluorocarbon B having m carbon atoms and having no double bonds, The above separation can obtain a third mixture in which the composition ratio of the above fluorocarbon A and the above fluorocarbon B is different from that of the above first mixture.

[0144] FIG. 2 schematically shows and describes an example of the system in this embodiment, a two-stage system.

[0145] In the system of FIG. 2, the above first mixture is stored in the gas tank 1. The first mixture is supplied to the first-stage separation module 4c through the pressure regulator 2a and the mass flow controller 3a. In one aspect, the back pressure of the first mixture supplied to the separation module 4c can be pressure-controlled by the pressure regulator 2a, but is not limited to such an aspect. The pressure regulator 2a can also be omitted.

[0146] The separation module 4c includes an adsorbent 11a, and the first mixture is supplied to the adsorbent 11a.

[0147] In the two-stage separation device, after contacting the adsorbent 11a, the flow rate of the third mixture is measured by the mass flow meter 5 and supplied to the second-stage separation module 4b through the pressure regulator 2b and the mass flow controller 3b. In one aspect, the back pressure of the third mixture supplied to the second-stage separation module 4b can be pressurized and controlled by the pressure regulator 2b, but is not limited to such an aspect. The pressure regulator 2b can also be omitted.

[0148] The second-stage separation module 4d is provided with an adsorbent 11b, and the third mixture is supplied to such an adsorbent 11b.

[0149] The new mixture separated by the contact between the third mixture and the adsorbent 11b is analyzed for its gas composition by the gas composition analyzer 8b through the pressure regulator 2c and then recovered into the recovery pipe 9. In one aspect, a mass flow meter may be used to measure the flow rate of the new mixture separated by contacting the adsorbent 11b. Also, in one aspect, the gas composition analyzer 8a can be omitted.

[0150] In this embodiment, a two-stage separation device has been described, but it is not limited thereto, and appropriate modifications can be made. For example, it may be a one-stage, three-stage, or four-stage or more separation device.

[0151] In the case of a p-stage (p is 3 or more), in the (p - 1)-th stage separation module, the (p - 1)-th mixture separated by contacting with the adsorbent is supplied to the separation module through a pressure regulator and a mass flow controller, and contacted with the adsorbent contained in the separation module to further separate a new p-th mixture. By recovering the p-th mixture after gas composition analysis that may be performed as necessary, the p-th stage separation can be carried out.

[0152] (Third Embodiment: Composite Material) A composite material containing a metal organic framework and the above-mentioned fluorocarbon A is also included in the technical scope of the present disclosure. The metal organic framework and fluorocarbon A have the same meaning as the metal organic framework and fluorocarbon A in the first embodiment.

[0153] In such a composite material, it is preferable that the metal-organic structure preferably contains a metal ion and one or more organic ligands. As the metal ion, one or more selected from Fe ion, Cu ion, Ni ion, Mg ion, Co ion, Cr ion, Zr ion and Zn ion are used, and preferably Fe 2+ 、Fe 3+ 、Cu 2+ 、Ni 2+ 、Mg 2+ 、Co 2+ 、Cr 3+ and Zn 2+ One or more selected from are more preferable. As the organic ligand, it is preferably selected from 1,4-benzenedicarboxylic acid, 1,2-benzenedicarboxylic acid, maleic acid, 1,3,5-benzenetricarboxylic acid, 4,4',4''-(1,3,5-benzenetriyl)trisbenzoic acid, 2,5-dihydroxy-1,4-benzenedicarboxylic acid, oxalic acid, 4,4'-dihydroxy-3,3'-biphenyldicarboxylic acid, 2-hydroxy-1,2,3-propanetricarboxylic acid, 4,4'-bipyridine, triazole, imidazole, 3,3'-bipyrazole, benzimidazole, and 3,5-pyridinedicarboxylic acid, and more preferably selected from 1,4-benzenedicarboxylic acid, 4,4'-dihydroxy-3,3'-biphenyldicarboxylic acid, 2-hydroxy-1,2,3-propanetricarboxylic acid, 1,3,5-benzenetricarboxylic acid and 2,5-dihydroxy-1,4-benzenedicarboxylic acid. The metal-organic structure preferably has an Open Metal Site.

[0154] In the composite material, the content of the fluorocarbon A is, for example, 1 part by mass or more and 100 parts by mass or less, preferably 10 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the metal-organic structure.

[0155] In addition to the above fluorocarbon and porous organic salt, the composite material may contain a resin. Examples of such resins include acrylic resin, polyurethane resin, polyolefin resin, polyester resin, polyamide resin, vinyl chloride resin, styrene resin, vinyl ether resin, polyvinyl alcohol resin, polycarbonate resin, polysulfone resin, and the like.

[0156] The composite material may contain additives such as emulsifiers, defoamers, surfactants, leveling agents, thickeners, viscoelasticity modifiers, defoamers, wetting agents, dispersants, preservatives, plasticizers, penetrants, fragrances, bactericides, acaricides, fungicides, ultraviolet absorbers, antioxidants, antistatic agents, flame retardants, dyes, pigments, and the like.

Examples

[0157] The present invention will be described more specifically by the following examples, but the present invention is not limited thereto.

[0158] Example 1, Comparative Example 1 As adsorbents, HKUST-1 (manufactured by Atomis) and CALF-20 (manufactured by Atomis) shown in Table 1 were used. As a pretreatment for the adsorbents used, vacuum treatment was performed at 130 ° C for 2 h.

[0159] (Measurement of adsorption breakthrough of mixed gas) A mixed gas of R1234yf / R134a = 10 mol% / 90 mol% was passed through an adsorption tower filled with the adsorbent shown in Table 1 at a total pressure of 0.4 MPaG, a temperature of 298 K, and a linear velocity of 0.4 cm / sec, and the concentration of R1234yf at the outlet of the adsorption tower was measured. The adsorption breakthrough curve showing the concentration change of R1234yf is shown in Figure 3. The R1234yf adsorption amount (amount per 1 g of adsorbent) obtained from the adsorption breakthrough curve is shown as the gas A adsorption amount in Table 1.

Table 1

Explanation of symbols

[0160] 1 Gas tank 2a, 2b, 2c Pressure regulators 3a, 3b Mass flow controllers 4a, 4b, 4c, 4d Separation modules 5 Mass flow meters 7 Step-up / step-down pressure regulators 8a, 8b Gas composition analyzers 9 Recovery piping 10a, 10b Adsorbents containing metal-organic frameworks 11a, 11b Adsorbents

Claims

1. From a first mixture containing a fluorocarbon A having n carbon atoms and one or more double bonds, and a fluorocarbon B having m carbon atoms and no double bonds, This includes separating a second mixture in which the composition ratio of fluorocarbon A and fluorocarbon B is different from that of the first mixture, The separation is carried out by bringing the first mixture into contact with an adsorbent containing a metal-organic structure. A method for separating fluorocarbons, wherein the boiling point of fluorocarbon A is between -80°C and -30°C.

2. The separation method according to claim 1, wherein the contact between the first mixture and the adsorbent containing the metal-organic structure is carried out at a temperature of -10°C to 80°C.

3. The separation method according to claim 1, wherein n is 2 or more and 3 or less.

4. The separation method according to claim 1, wherein m is 1 or more and 3 or less.

5. The separation method according to claim 1, wherein the fluorocarbon A contains R1234yf.

6. The separation method according to claim 1, wherein the fluorocarbon B comprises one or more selected from R134a, R143, R143a, R32, and R125.

7. The separation method according to claim 1, wherein the metal-organic structure contains metal ions.

8. The separation method according to claim 1, wherein the metal-organic structure comprises one or more organic ligands, and each organic ligand contains two or more groups in one molecule that can coordinately bond to a metal ion.

9. The separation method according to claim 1, wherein the metal-organic structure comprises a metal ion and one or more organic ligands, and the organic ligand contains two or more groups in one molecule that can coordinately bond to the metal ion.

10. The separation method according to claim 1, wherein the metal-organic structure has open metal sites consisting of coordination-unsaturated metal ions.

11. The separation method according to claim 1, wherein the adsorbent containing the metal-organic structure further comprises a resin.

12. The separation method according to claim 1, wherein the adsorbent containing the metal-organic structure is in the form of a powder, granules, flakes, or pellets.

13. The separation method according to claim 1, wherein the first mixture is an azeotropic mixture or pseudoazeotropic mixture of fluorocarbons.

14. The separation method according to any one of claims 1 to 13, further comprising contacting the separated second mixture with the adsorbent containing the metal-organic structure.

15. The separation method according to any one of claims 1 to 13, further comprising purifying the separated second mixture.

16. After bringing the first mixture into contact with the adsorbent containing the metal-organic structure, The separation method according to any one of claims 1 to 13, further comprising desorbing the fluorocarbon A adsorbed on the adsorbent containing the metal-organic structure from the adsorbent containing the metal-organic structure.

17. A fluorocarbon purification system that carries out the separation method described in any one of claims 1 to 13.

18. From a first mixture containing a fluorocarbon A having n carbon atoms and one or more double bonds, and a fluorocarbon B having m carbon atoms and no double bonds, This includes separating a third mixture in which the concentration of fluorocarbon A is lower than that of the first mixture, The separation is carried out by bringing the first mixture into contact with the adsorbent. A method for separating fluorocarbons, wherein the boiling point of fluorocarbon A is between -80°C and -30°C.

19. The separation method according to claim 18, wherein the contact between the first mixture and the adsorbent is carried out at a temperature of -10°C to 80°C.

20. The separation method according to claim 18, wherein n is 2 or more and 3 or less.

21. The separation method according to claim 18, wherein m is 1 or more and 3 or less.

22. The separation method according to claim 18, wherein the fluorocarbon A includes R1234yf.

23. The separation method according to claim 18, wherein the fluorocarbon B comprises one or more selected from R134a, R143, R143a, R32, and R125.

24. The separation method according to claim 18, wherein the adsorbent includes a porous body.

25. The separation method according to claim 18, wherein the adsorbent includes an organometallic structure.

26. The separation method according to claim 25, wherein the metal-organic structure contains metal ions.

27. The separation method according to claim 25, wherein the metal-organic structure comprises one or more organic ligands, and each organic ligand contains two or more groups in one molecule that can coordinately bond to a metal ion.

28. The separation method according to claim 25, wherein the metal-organic structure comprises a metal ion and one or more organic ligands, and the organic ligand contains two or more groups in one molecule that can coordinately bond to the metal ion.

29. The separation method according to claim 25, wherein the metal-organic structure has open metal sites consisting of coordination-unsaturated metal ions.

30. The separation method according to claim 18, wherein the adsorbent further comprises a resin.

31. The separation method according to claim 18, wherein the adsorbent is in the form of a powder, granules, flakes, or pellets.

32. The separation method according to claim 18, wherein the first mixture is an azeotropic mixture or pseudoazeotropic mixture of fluorocarbons.

33. The separation method according to any one of claims 18 to 32, further comprising contacting the separated third mixture with an adsorbent.

34. The separation method according to any one of claims 18 to 32, further comprising purifying the separated third mixture.

35. After bringing the first mixture into contact with the adsorbent, The separation method according to any one of claims 18 to 32, further comprising desorbing the fluorocarbon A adsorbed on the adsorbent from the adsorbent.

36. A fluorocarbon purification system that carries out the separation method described in any one of claims 18 to 32.

37. It comprises a metal-organic structure and a fluorocarbon A having one or more double bonds and n carbon atoms. The aforementioned metal-organic structure has open metal sites consisting of coordination-unsaturated metal ions, A composite material wherein the boiling point of the fluorocarbon A is between -80°C and -30°C.

Images