WO2020026542A1 - Separation membrane - Google Patents

Separation membrane Download PDF

Info

Publication number
WO2020026542A1
WO2020026542A1 PCT/JP2019/017392 JP2019017392W WO2020026542A1 WO 2020026542 A1 WO2020026542 A1 WO 2020026542A1 JP 2019017392 W JP2019017392 W JP 2019017392W WO 2020026542 A1 WO2020026542 A1 WO 2020026542A1
Authority
WO
WIPO (PCT)
Prior art keywords
zeolite
membrane
separation
molar ratio
separation membrane
Prior art date
Application number
PCT/JP2019/017392
Other languages
French (fr)
Japanese (ja)
Inventor
正也 板倉
Original Assignee
日立造船株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日立造船株式会社 filed Critical 日立造船株式会社
Publication of WO2020026542A1 publication Critical patent/WO2020026542A1/en

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/10—Supported membranes; Membrane supports
    • B01D69/108—Inorganic support material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/10—Supported membranes; Membrane supports
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/12—Composite membranes; Ultra-thin membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/02—Inorganic material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/02—Inorganic material
    • B01D71/0215—Silicon carbide; Silicon nitride; Silicon oxycarbide
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B39/00—Compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites; Their preparation; After-treatment, e.g. ion-exchange or dealumination
    • C01B39/02—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof; Direct preparation thereof; Preparation thereof starting from a reaction mixture containing a crystalline zeolite of another type, or from preformed reactants; After-treatment thereof
    • C01B39/46—Other types characterised by their X-ray diffraction pattern and their defined composition
    • C01B39/48—Other types characterised by their X-ray diffraction pattern and their defined composition using at least one organic template directing agent

Definitions

  • the present invention relates to a separation membrane in which a zeolite crystal is supported on a porous substrate, and more specifically, to a separation membrane having a use for separating a specific molecule from a fluid in which a plurality of types of molecules coexist.
  • Patent Literature 1 describes a zeolite separation membrane having a use for separating a specific molecule from a fluid in which a plurality of types of molecules coexist and a method for producing the same.
  • Patent Document 1 a porous support is immersed in an aluminosilicate gel having H 2 O, Na 2 O, SiO 2 and each component of tetrapropylammonium halide (TPAX) in a specific molar composition.
  • ZSM-5 type zeolite membrane is manufactured through hydrothermal synthesis. Unlike conventional organic liquid mixture separation membranes, the ZSM-5 type zeolite membrane produced by this method is excellent in heat resistance, solvent resistance, and chemical resistance, and requires a small amount of energy consumption and is efficiently used as a liquid. It is said that it is possible to separate
  • Patent Document 2 by the same applicant as Patent Document 1 described above describes a mixture separation membrane device capable of further improving the separation performance as compared with the zeolite membrane described in Patent Document 1.
  • Patent Literature 2 discloses that in a membrane production method as described in Patent Literature 1, a sodium liquor based on sodium hydroxide is contained in a mother liquor for forming a ZSM-5 type zeolite membrane. As a result of sodium ions remaining in the -5 type zeolite membrane, the ZSM-5 type zeolite membrane assumes hydrophilicity due to the presence of sodium ions, and the separation performance is reduced by that amount.
  • a method is described in which a porous supporting substrate is immersed in a mother liquor for forming a ZSM-5 type zeolite membrane, and crystals are grown to form a ZSM-5 type zeolite membrane.
  • the zeolite separation membrane formed therefrom has higher separation performance in water-alcohol separation than the zeolite separation membrane described in Patent Document 1.
  • the present invention has been made in view of such circumstances, and has as its object to provide a separation membrane having excellent separation performance even in gas separation.
  • the present inventors have conducted intensive studies to solve the above-described problems, and as a result, have found that by promoting the stabilization and crystallization of the zeolite structure, a separation membrane having high separation performance in separating a fluid, particularly a gas, can be obtained. As a result, the present invention has been completed.
  • the separation membrane of the present invention is a separation membrane in which a zeolite crystal is supported on a porous substrate, wherein the zeolite has a Si / Na 2 O molar ratio of 100 to 6500. .
  • the zeolite preferably has pores of 10 membered rings or less.
  • the zeolite preferably has an MFI structure.
  • the zeolite contains only the elements of H, O, Si and Na.
  • the present invention relates to a separation membrane in which a zeolite crystal is supported on a porous substrate, wherein the zeolite has a Si / Na 2 O molar ratio of 100 to 6500, or a H 2 O / Na 2 O molar ratio. Is obtained by using a zeolite membrane-forming reaction solution containing sodium so that the content thereof becomes 3500 to 100,000.
  • the separation membrane according to the present invention having the above-mentioned characteristics has a higher gas permeability ratio before and after pore closure than the conventional synthesis method in a palm porometry test. That is, it has high separation performance in separating fluids such as gas and liquid.
  • FIG. 3 is a view showing an XRD pattern as an analysis result of an X-ray diffractometer (XRD) for the zeolite membrane obtained in Example 1.
  • XRD X-ray diffractometer
  • the H 2 O / Na 2 O molar ratio the horizontal axis (X axis), the permeability ratio vertical axis (Y-axis) is a graph showing these relationships.
  • the Si / Na 2 O molar ratio the horizontal axis (X axis), the permeability ratio vertical axis (Y-axis) is a graph showing these relationships.
  • the separation membrane of the present invention more specifically, the separation membrane in which a zeolite crystal is supported on a porous substrate will be described in detail.
  • the separation membrane of the present invention is a separation membrane in which a zeolite crystal is supported on a porous substrate, and the zeolite has a Si / Na 2 O molar ratio of 100 to 6500 or H 2 O / Na 2 It is obtained using a zeolite membrane-forming reaction solution having an O molar ratio of 3500 to 100,000.
  • zeolite membranes having high separation performance in separating liquids do not always show excellent separation performance in separating gas.
  • a zeolite membrane having a high separation performance in gas separation has no defects or is regarded as extremely rare, and accordingly, there is no or rare permeation path other than the zeolite pores. Therefore, such a zeolite membrane can be expected to have high separation performance even in liquid separation.
  • Patent Document 1 JP-A-8-257302
  • Patent Document 2 JP-A-2002-18247
  • Patent Documents 1 and 2 both provide a liquid mixture separation membrane.
  • the molar ratio of H 2 O / Na 2 O in a synthesis gel for synthesizing zeolite is in the range of 20 to 60, and a zeolite membrane produced based on such a synthesis gel has In addition, the separation performance is reduced due to the large amount of sodium related to zeolite.
  • Patent Literature 2 points out such a problem of Patent Literature 1, and Patent Literature 2 describes that the use of a sodium-free synthetic gel has led to the production of a zeolite membrane with improved separation performance. Claims such a zeolite membrane.
  • any of the above-mentioned documents is to be applied to a separation membrane for separating a liquid mixture, and the present inventors have proposed a method for separating gas using a separation membrane described in Patent Document 2.
  • the separation performance was evaluated assuming the following, the result was that the separation performance was low.
  • the present inventors believe that the low separation performance obtained in the above gas separation is due to not using sodium having a function of promoting the stabilization and crystallization of the zeolite structure in forming the zeolite membrane.
  • the present inventors have suppressed the decrease in the separation performance of the zeolite membrane by using a synthetic gel containing sodium in a much smaller amount than the amount of sodium described in Patent Document 1.
  • the porous substrate may be any material conventionally used for separating a liquid or gaseous fluid, as long as it can support zeolite crystals.
  • alumina, silica, zirconia, mullite, titania, silicon carbide, stainless steel and the like can be mentioned, and alumina is particularly preferable.
  • Zeolite generally means a kind of aluminosilicate crystals, also called zeolite.
  • silicon and aluminum form tetrahedral structural units surrounded by four oxygens (oxide ions), which are connected to each other via oxygen to form a three-dimensional framework structure.
  • Zeolite has pores having a diameter of about several hundred pm in its crystal structure.
  • the pores present in such a zeolite structure have a size of about a predetermined molecule, and have a property of adsorbing molecules, and in particular, adsorb and pass molecules smaller than the pore diameter, and Since large molecules are not allowed to pass through, molecules having different sizes and shapes can be sieved using the pores.
  • zeolite has different pore sizes depending on its type. Since the atomic diameter of silicon, which is a skeletal element of zeolite, is smaller than that of oxygen, the size of pores is usually represented by the number of oxygen, and a “member ring” is generally used. Specifically, the n-membered ring represents a pore having a ring structure containing n oxygen atoms. The size of the pores that the zeolite should have depends on the size of the molecule to be separated. In the present invention, hydrocarbons are assumed to be separated, and in this regard, it is assumed that the zeolite constituting the separation membrane of the present invention has pores of a 10-membered ring in order to separate the zeolite. Are preferred.
  • zeolite is generally known to have various types of structures, and a structural type is defined to classify these, and AEI, ANA, BEA, CDO, CHA, DDR, EAB, ERI , FAU, FER, LEV, LTA, LTL, MEL, MER, MFI, MOR, MTW, RHO, and the like.
  • the structure type of the produced zeolite mainly depends on the structure directing agent used.
  • a zeolite membrane having an MFI type structure could be produced by using tetrapropylammonium hydroxide as a structure directing agent.
  • the structure-directing agent examples include, in addition to the above tetrapropylammonium cation (hydroxide), a four-coordinate organic ammonium cation such as a tetramethylammonium cation, a tetraethylammonium cation, a tetrabutylammonium cation, and a trimethyladamantylammonium cation. be able to.
  • zeolite is generally a kind of aluminosilicate crystal and contains silicon and aluminum.
  • the ratio of the number of silicon and aluminum affects the function of zeolite as a molecular sieve.
  • the proportion of silicon is high, the skeleton becomes more hydrophobic, and zeolites with a very high proportion of silicon are also known.
  • zeolite containing no aluminum is commonly used in the industry because aluminum is not used as a starting material. (JP-A-8-257302 and JP-A-2002-18247).
  • Also includes zeolites that do not contain aluminum.
  • the zeolite preferably used in the present invention contains silicon (Si) and oxygen (O) as elements forming the skeleton.
  • the zeolite finally obtained from the water and sodium (Na) components contained in the starting material contains hydrogen (H) and sodium.
  • preferred constituent elements of the separation membrane in the present invention are only Si, O, H and Na.
  • a minute amount of impurity element derived from the porous support tube or the reactor for synthesizing zeolite may be included in the separation membrane.
  • the term “only” does not exclude that such unintended impurities are included in the separation membrane.
  • the present invention relates to a zeolite membrane-forming reaction solution containing sodium so that the zeolite has a Si / Na 2 O molar ratio of 100 to 6500 or an H 2 O / Na 2 O molar ratio of 3500 to 100,000. It has been found that a separation membrane having excellent performance mainly in gas separation can be obtained by using the same.
  • the sodium element is an alkali metal belonging to Group 1A of the periodic table of elements, and it is generally known as common technical knowledge that elements belonging to the same group on the periodic table of the element have the same effect. Instead, even if an alkali metal cation such as K, Li, Rb, or Cs is used, a similar effect, that is, an effect of accelerating the crystallization of zeolite will be naturally obtained.
  • the molar ratio of H 2 O / Na 2 O included in the zeolite membrane-forming reaction solution for producing the zeolite membrane is set to be in the range of 3500 to 100,000. This molar ratio is more preferably in the range of 4000 to 60000, and even more preferably in the range of 8000 to 20,000.
  • the molar ratio of H 2 O / Na 2 O is a value calculated from the moles of H 2 O and Na 2 O added to the zeolite membrane-forming reaction solution.
  • the separation of the zeolite membrane is performed. Although the performance is high, the molar ratio is more preferably in the range of 300 to 5,000, and even more preferably in the range of 400 to 1,000.
  • the molar ratio of Si / Na 2 O in the zeolite membrane can be measured and calculated by EDX (energy dispersive X-ray analysis).
  • the separation membrane according to the present invention can be manufactured by roughly performing the following steps (1) to (3).
  • the water may be ion-exchanged water, distilled water, or the like.
  • the Na component include sodium hydroxide and sodium chloride
  • examples of the Si component include silicic acid, silicate, fumed silica, and ethyl silicate.
  • Na-containing colloidal silica may also be used, as in the examples below, which have both.
  • Examples of the structure-directing agent include tetrapropylammonium hydroxide, but may be other ones as described above.
  • the time required for mixing is, for example, 5 minutes to 24 hours, but is not particularly limited.
  • the obtained mixture is in the form of an aqueous solution, suspension, gel or the like, but is not particularly limited as long as it is in a form suitable for the next synthesis reaction.
  • the molar ratio of H 2 O / Na 2 O in the mixture is 3500 to 100,000.
  • the reactor for synthesizing the zeolite is selected from various conventionally known reactors that can withstand high temperature and high pressure during the reaction.
  • An example is an autoclave. It is preferable to have equipment capable of stirring during the synthesis of the zeolite membrane.
  • the reaction conditions in the reactor include, for example, temperature: 100 ° C. to 200 ° C., and reaction time: 8 hours to 48 hours, and are appropriately selected depending on the intended zeolite film thickness.
  • the washing, drying and baking in the above step (3) are performed by a conventionally known method.
  • water for example, water (ion-exchanged water, distilled water, or the like) is used.
  • Drying conditions include a temperature of room temperature to 150 ° C., and a drying furnace, for example, is used for drying.
  • the firing conditions include a temperature of 350 to 800 ° C. The firing is performed using, for example, an electric furnace or a gas furnace.
  • Example 2 Hereinafter, a separation membrane conforming to the present invention was specifically manufactured, and a test for demonstrating its effect was performed. These will be described as examples. Further, a separation membrane not conforming to the present invention for comparison with the examples was prepared, and the effect of such a separation membrane was measured in the same manner.
  • the following examples are examples of the separation membrane of the present invention, and the scope of the present invention is not limited to those shown in these examples.
  • an alumina porous tube (length: 28 mm; outer diameter: 16 mm) coated with the MFI zeolite crystal was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
  • FIG. 1 shows an XRD pattern as an analysis result. Since the XRD pattern shown in FIG. 1 has a peak characteristic of the MFI structure, it was found that this zeolite membrane had the MFI structure.
  • an alumina porous tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
  • a palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1. As a result, the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 118.0. The result was that there was.
  • an alumina porous tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
  • a palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the permeability when supplying only nitrogen to the permeability when supplying nitrogen and normal hexane was 62.1. The result was that there was.
  • an alumina porous tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
  • a palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 56.2. The result was that there was.
  • an alumina support tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 100 ° C. After 168 hours, the autoclave was cooled, the alumina support tube was taken out, and washed with ion-exchanged water. After drying the alumina support tube, it was calcined at 500 ° C. for 6 hours to obtain a zeolite membrane.
  • the molar ratio of Si / Na 2 O in this zeolite membrane is infinite because Na is not used in the synthesis.
  • a palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 19.1. The result was that there was.
  • an alumina support tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 170 ° C. After a lapse of 48 hours, the autoclave was cooled, the alumina support tube was taken out, and washed with ion-exchanged water. After drying the alumina support tube, it was calcined at 500 ° C. for 6 hours to obtain a zeolite membrane.
  • a palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 21.8. The result was that there was.
  • the palm porometry test was performed using N 2 gas which is a non-condensable gas and n-hexane which is a condensable gas.
  • the permeation characteristics in the palm porometry test are evaluated by comparing the permeabilities of a gas of N 2 alone and a gas mixture of N 2 + n-hexane. Specifically, if a condensable gas is present and supplied to the zeolite membrane, the condensable gas can block only the zeolite pores of the zeolite membrane.
  • the ratio of the gas permeability is calculated as follows, and the larger the ratio of the gas permeability, the higher the separation performance.
  • Examples 5 to 7 A zeolite membrane was prepared in the same manner as in Example 1, except that a 1 m-long alumina porous tube was used.
  • Examples 5 to 7 colloidal silica having a SiO 2 / Na 2 O molar ratio of 100 (constant) was used, and the amount of water in the synthesis gel was varied. As a result, three types of synthetic gels having different H 2 O / Na 2 O molar ratios could be prepared, and zeolite membranes of Examples 5 to 7 were prepared using these three types of synthetic gels.
  • Table 1 summarizes the relationship between the H 2 O / Na 2 O molar ratio in the synthesis gel, the Si / Na 2 O molar ratio of the zeolite membrane, and the transmittance ratio in Examples 1 to 4.
  • Table 2 summarizes the relationship between the H 2 O / Na 2 O molar ratio in the synthesis gel, the Si / Na 2 O molar ratio of the zeolite membrane, and the transmittance ratio in Examples 5 to 7.
  • the value of 35 was used as the boundary value for the quality of the transmittance.
  • the H 2 O / Na 2 O molar ratio is lower than 2000
  • the Si / Na 2 O molar ratio is lower than 799, these ratios become large (X-axis positive direction).
  • the transmittance ratio (the positive direction of the Y axis) increases. This is because the molar ratio of H 2 O / Na 2 O or the molar ratio of Si / Na 2 O increases, that is, the smaller the amount of Na, the higher the transmittance ratio, and the zeolite membrane to be produced contains sodium. It is thought that this is reflected in the improvement of the transmittance ratio because the amount decreases and the hydrophobicity increases.
  • the separation membrane which is a zeolite membrane having the characteristics of the present invention, that is, the molar ratio of Si / Na 2 O is 100 to 6500, or the molar ratio of H 2 O / Na 2 O is 3500 to
  • a product obtained by using a zeolite membrane-forming reaction solution containing sodium so as to have a concentration of 100,000 has high separation performance in separating fluids such as gas and liquid.
  • the separation membrane of the present application is applicable to, for example, separation of water-organic solvent in separation of liquid.
  • gas separation it is used for selective separation of molecules smaller than hydrocarbons such as hydrogen-toluene and for separation of linear hydrocarbons and branched hydrocarbons such as normal butane and isobutane.
  • Test example In this test example, a test was conducted in which normal butane / isobutane was separated using the zeolite membrane prepared as described in Examples 6 and 7.
  • a mixed gas of n-butane: isobutane was supplied to the supply side of the separation device.
  • the molar ratio of n-butane: isobutane in this mixed gas was 53:47. This molar ratio was measured using a gas chromatograph (manufactured by SHIMADZU). The temperature of the supply gas was adjusted to 150 ° C. and the pressure was adjusted to 0.1 MPa (A).
  • Helium gas was passed through the permeate side of the zeolite membrane.
  • the temperature on the transmission side was adjusted to room temperature, and the pressure was adjusted to 0.1 MPa (A).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)

Abstract

Provided is a separation membrane that exhibits excellent separation performance even for separation of gases. This separation membrane is a separation membrane in which zeolite crystals are supported on a porous base material, and is characterized in that the Si/Na2O molar ratio in the zeolite is 100-6,500. In addition, another separation membrane of the present invention is a separation membrane in which zeolite crystals are supported on a porous base material, and is characterized by being obtained using a reaction liquid for a zeolite membrane, which contains sodium at a quantity whereby the H2O/Na2O molar ratio is 3,500-100,000.

Description

分離膜Separation membrane
　本発明は、多孔質基材にゼオライト結晶が支持されてなる分離膜、より具体的には、複数種の分子が共存する流体から特定の分子を分離するための用途を有する分離膜に関する。 (4) The present invention relates to a separation membrane in which a zeolite crystal is supported on a porous substrate, and more specifically, to a separation membrane having a use for separating a specific molecule from a fluid in which a plurality of types of molecules coexist.
　複数種の分子が共存する流体から特定の分子を分離するための用途を有するゼオライト分離膜およびその製造方法を記載したものとして、例えば、特許文献１が挙げられる。 Patent Literature 1 describes a zeolite separation membrane having a use for separating a specific molecule from a fluid in which a plurality of types of molecules coexist and a method for producing the same.
　特許文献１では、Ｈ２Ｏ、Ｎａ２Ｏ、ＳｉＯ２およびテトラプロピルアンモニウムハロゲン化物（ＴＰＡＸ）の各成分を特定のモル組成で有するアルミノシリケートゲル中に、多孔質支持体を浸漬し、その後の水熱合成を経てＺＳＭ－５型ゼオライト膜を製造している。この方法により製造されたＺＳＭ－５型ゼオライト膜は、従来の有機質液体混合物分離膜と異なり、耐熱性、耐溶剤性、および耐薬品性に優れており、しかも少ないエネルギー消費量で、効率よく液体を分離することが可能である、とされている。 In Patent Document 1, a porous support is immersed in an aluminosilicate gel having H 2 O, Na 2 O, SiO 2 and each component of tetrapropylammonium halide (TPAX) in a specific molar composition. ZSM-5 type zeolite membrane is manufactured through hydrothermal synthesis. Unlike conventional organic liquid mixture separation membranes, the ZSM-5 type zeolite membrane produced by this method is excellent in heat resistance, solvent resistance, and chemical resistance, and requires a small amount of energy consumption and is efficiently used as a liquid. It is said that it is possible to separate
　上記の特許文献１と同一の出願人による特許文献２には、特許文献１に記載されたゼオライト膜よりも分離性能を一層向上させることのできる混合物分離膜装置が記載されている。 特許 Patent Document 2 by the same applicant as Patent Document 1 described above describes a mixture separation membrane device capable of further improving the separation performance as compared with the zeolite membrane described in Patent Document 1.
　特許文献２には、特許文献１に記載されたような膜製造方法では、ＺＳＭ－５型ゼオライト膜形成用の母液に、水酸化ナトリウムに基づくナトリウムが含まれているため、製膜されたＺＳＭ－５型ゼオライト膜中にナトリウムイオンが残存する結果、ナトリウムイオンの存在によって該ＺＳＭ－５型ゼオライト膜が親水性を帯び、その分だけ分離性能が低下するとみなして、成分中にナトリウムを含まないＺＳＭ－５型ゼオライト膜形成用の母液中に多孔質支持基体を浸漬し、結晶成長させてＺＳＭ－５型ゼオライト膜を形成させる方法が記載されている。 Patent Literature 2 discloses that in a membrane production method as described in Patent Literature 1, a sodium liquor based on sodium hydroxide is contained in a mother liquor for forming a ZSM-5 type zeolite membrane. As a result of sodium ions remaining in the -5 type zeolite membrane, the ZSM-5 type zeolite membrane assumes hydrophilicity due to the presence of sodium ions, and the separation performance is reduced by that amount. A method is described in which a porous supporting substrate is immersed in a mother liquor for forming a ZSM-5 type zeolite membrane, and crystals are grown to form a ZSM-5 type zeolite membrane.
　特許文献２に記載された方法により製造されたゼオライト膜は、母液にナトリウムが含まれていないことにより、製膜されたＺＳＭ－５型ゼオライト膜にもナトリウムイオンが残存することはなく、その結果、混合物分離膜装置としての分離性能を一層向上させることができた、としている。
特開平８－２５７３０２号公報 特開２００２－１８２４７号公報 In the zeolite membrane manufactured by the method described in Patent Document 2, since sodium is not contained in the mother liquor, no sodium ion remains in the formed ZSM-5 type zeolite membrane. It is said that the separation performance as a mixture separation membrane device could be further improved.
JP-A-8-257302 JP-A-2002-18247
　特許文献２の記載によれば、そこで製膜されたゼオライト分離膜は、特許文献１に記載されたゼオライト分離膜よりも水－アルコール分離における分離性能が高い、としている。 According to the description of Patent Document 2, the zeolite separation membrane formed therefrom has higher separation performance in water-alcohol separation than the zeolite separation membrane described in Patent Document 1.
　しかしながら、本出願人は、特許文献２と同様のナトリウムを含まないＺＳＭ－５型ゼオライト膜を形成し、これを用いて気体の分離を想定した分離性能評価試験を行ったが、性能の低い結果となった（本明細書において後述の比較例１において具体的に説明される）。 However, the present applicant formed a sodium-free ZSM-5 type zeolite membrane similar to that of Patent Document 2 and performed a separation performance evaluation test on the assumption of gas separation using the same. (This will be specifically described in Comparative Example 1 described later in this specification).
　したがって、気体の分離を行うに際して優れた分離性能を有するゼオライト膜を得るための方法を開発することが望まれている。 Therefore, it is desired to develop a method for obtaining a zeolite membrane having excellent separation performance when separating gases.
　本発明は、このような事情に鑑みてなされたものであり、気体の分離においても優れた分離性能を有する分離膜を提供することを目的とする。 The present invention has been made in view of such circumstances, and has as its object to provide a separation membrane having excellent separation performance even in gas separation.
　本発明者らは、上記課題を解決するため鋭意検討した結果、ゼオライト構造の安定化と結晶化を促進させることにより、流体、特に気体の分離において高い分離性能を有する分離膜が得られることを見出し、本発明を完成するに至った。 The present inventors have conducted intensive studies to solve the above-described problems, and as a result, have found that by promoting the stabilization and crystallization of the zeolite structure, a separation membrane having high separation performance in separating a fluid, particularly a gas, can be obtained. As a result, the present invention has been completed.
　すなわち、本発明の分離膜は、多孔質基材にゼオライト結晶が支持されてなる分離膜であって、ゼオライトのＳｉ／Ｎａ２Ｏモル比が１００～６５００であることを特徴とするものである。 That is, the separation membrane of the present invention is a separation membrane in which a zeolite crystal is supported on a porous substrate, wherein the zeolite has a Si / Na 2 O molar ratio of 100 to 6500. .
　また、本発明の他の分離膜は、多孔質基材にゼオライト結晶が支持されてなる分離膜であって、Ｈ２Ｏ／Ｎａ２Ｏモル比が３５００～１０００００になるようにナトリウムを含むゼオライト製膜用反応液を用いて得られることを特徴とするものである。 Another separation membrane of the present invention is a separation membrane in which a zeolite crystal is supported on a porous substrate, and the sodium-containing zeolite has a H 2 O / Na 2 O molar ratio of 3500 to 100,000. It is obtained by using a reaction solution for film formation.
　上記の分離膜において、ゼオライトは、１０員環以下の細孔を有することが好ましい。 に お い て In the above separation membrane, the zeolite preferably has pores of 10 membered rings or less.
　上記の分離膜において、ゼオライトは、ＭＦＩ構造を有することが好ましい。 に お い て In the above separation membrane, the zeolite preferably has an MFI structure.
　上記の分離膜において、ゼオライトに、Ｈ、Ｏ、ＳｉおよびＮａの元素のみが含まれることが好ましい。 に お い て In the above separation membrane, it is preferable that the zeolite contains only the elements of H, O, Si and Na.
　本発明は、多孔質基材にゼオライト結晶が支持されてなる分離膜であって、ゼオライトのＳｉ／Ｎａ２Ｏモル比が１００～６５００であるか、または、Ｈ２Ｏ／Ｎａ２Ｏモル比が３５００～１０００００になるようにナトリウムを含むゼオライト製膜用反応液を用いて得られるものである。 The present invention relates to a separation membrane in which a zeolite crystal is supported on a porous substrate, wherein the zeolite has a Si / Na 2 O molar ratio of 100 to 6500, or a H 2 O / Na 2 O molar ratio. Is obtained by using a zeolite membrane-forming reaction solution containing sodium so that the content thereof becomes 3500 to 100,000.
　上記特徴を有する本発明に係る分離膜は、パームポロメトリー試験において従来の合成法より細孔の閉塞前後でのガス透過性の比が高かった。すなわち、気体および液体などの流体の分離において高い分離性能を有する。 (4) The separation membrane according to the present invention having the above-mentioned characteristics has a higher gas permeability ratio before and after pore closure than the conventional synthesis method in a palm porometry test. That is, it has high separation performance in separating fluids such as gas and liquid.
実施例１で得られたゼオライト膜についてＸ線回折装置（ＸＲＤ）の分析結果であるＸＲＤパターンを示す図である。FIG. 3 is a view showing an XRD pattern as an analysis result of an X-ray diffractometer (XRD) for the zeolite membrane obtained in Example 1. Ｈ２Ｏ／Ｎａ２Ｏモル比を横軸（Ｘ軸）とし、透過度比を縦軸（Ｙ軸）とする、これらの関係を示すグラフである。The H 2 O / Na 2 O molar ratio the horizontal axis (X axis), the permeability ratio vertical axis (Y-axis) is a graph showing these relationships. Ｓｉ／Ｎａ２Ｏモル比を横軸（Ｘ軸）とし、透過度比を縦軸（Ｙ軸）とする、これらの関係を示すグラフである。The Si / Na 2 O molar ratio the horizontal axis (X axis), the permeability ratio vertical axis (Y-axis) is a graph showing these relationships.
　以下、本発明の分離膜、より具体的には、多孔質基材にゼオライト結晶が支持されてなる分離膜について詳細に説明する。 Hereinafter, the separation membrane of the present invention, more specifically, the separation membrane in which a zeolite crystal is supported on a porous substrate will be described in detail.
　（分離膜）
　本発明の分離膜は、多孔質基材にゼオライト結晶が支持されてなる分離膜であって、ゼオライトのＳｉ／Ｎａ２Ｏモル比が１００～６５００であるか、または、Ｈ２Ｏ／Ｎａ２Ｏモル比が３５００～１０００００であるゼオライト製膜用反応液を用いて得られるものである。 (Separation membrane)
The separation membrane of the present invention is a separation membrane in which a zeolite crystal is supported on a porous substrate, and the zeolite has a Si / Na 2 O molar ratio of 100 to 6500 or H 2 O / Na 2 It is obtained using a zeolite membrane-forming reaction solution having an O molar ratio of 3500 to 100,000.
　一般に、ゼオライト膜による液体の分離では、ゼオライト膜への分離対象物の吸着が強く作用することが知られている。そのため、欠陥により生じたゼオライト孔以外の透過経路がゼオライト膜に存在していても、このような欠陥による透過経路は、分離対象の分子によって閉塞され、一定水準の分離性能が発揮される。 Generally, it is known that in the separation of a liquid by a zeolite membrane, the adsorption of an object to be separated on the zeolite membrane acts strongly. Therefore, even if a zeolite membrane has a permeation path other than the zeolite pores generated by the defect, the permeation path due to such a defect is blocked by the molecules to be separated, and a certain level of separation performance is exhibited.
　これに対して、気体を分離する場合では、液体の場合と異なり吸着の作用が小さいため、ゼオライト孔以外の透過経路が欠陥によりゼオライト膜に生じていると、このような欠陥は分離対象物により閉塞されない。そのため、ゼオライト孔以外の透過経路から分離対象でない分子も透過し、ゼオライト膜の分離性能は低下する。 On the other hand, in the case of separating gas, the effect of adsorption is small unlike the case of liquid, so if a permeation path other than zeolite pores is generated in the zeolite membrane due to defects, such defects will be caused by the separation target Not blocked. Therefore, molecules not to be separated also pass through the permeation path other than the zeolite pores, and the separation performance of the zeolite membrane is reduced.
　このように、液体の分離で高い分離性能を持つゼオライト膜が必ずしも気体の分離においても優れた分離性能を示すとは限らない。しかしながら、気体の分離で高い分離性能を有するゼオライト膜は、欠陥が存在しないかまたは極めて希少なものとみなされるものであり、これに伴って、ゼオライト孔以外の透過経路も存在しないかまたは希少なものであるため、このようなゼオライト膜は、液体の分離においても高い分離性能を期待することができる。 Thus, zeolite membranes having high separation performance in separating liquids do not always show excellent separation performance in separating gas. However, a zeolite membrane having a high separation performance in gas separation has no defects or is regarded as extremely rare, and accordingly, there is no or rare permeation path other than the zeolite pores. Therefore, such a zeolite membrane can be expected to have high separation performance even in liquid separation.
　従来技術として引用した特開平８－２５７３０２号公報（特許文献１）および特開２００２－１８２４７号公報（特許文献２）にそれぞれ記載された事項を用いてより具体的に説明する。 (4) A more specific description will be given using the matters described in JP-A-8-257302 (Patent Document 1) and JP-A-2002-18247 (Patent Document 2) cited as the prior art.
　特許文献１および２は、いずれも、液体混合物分離膜を提供したものである。先行する特許文献１では、ゼオライトを合成するための合成ゲル中のＨ２Ｏ／Ｎａ２Ｏモル比が２０～６０の範囲内であり、このような合成ゲルに基づいて作製されたゼオライト膜では、ゼオライトに関連するナトリウム量が多いため分離性能が低くなる。このような特許文献１の課題を特許文献２において指摘したうえ、特許文献２では、ナトリウムを含まない合成ゲルを使用することで分離性能が向上したゼオライト膜を作製するに至ったことが記載され、このようなゼオライト膜を特許請求している。 Patent Documents 1 and 2 both provide a liquid mixture separation membrane. In Patent Document 1, the molar ratio of H 2 O / Na 2 O in a synthesis gel for synthesizing zeolite is in the range of 20 to 60, and a zeolite membrane produced based on such a synthesis gel has In addition, the separation performance is reduced due to the large amount of sodium related to zeolite. Patent Literature 2 points out such a problem of Patent Literature 1, and Patent Literature 2 describes that the use of a sodium-free synthetic gel has led to the production of a zeolite membrane with improved separation performance. Claims such a zeolite membrane.
　しかしながら、上記に挙げた文献はいずれも、液体混合物を分離するための分離膜に適用されるべきものであり、本発明者らが、特許文献２に記載された分離膜を用いて気体の分離を想定した分離性能評価を行ったところ、分離性能は低くなる結果となった。 However, any of the above-mentioned documents is to be applied to a separation membrane for separating a liquid mixture, and the present inventors have proposed a method for separating gas using a separation membrane described in Patent Document 2. When the separation performance was evaluated assuming the following, the result was that the separation performance was low.
　上記の気体分離において低い分離性能が得られたのは、ゼオライト膜の形成においてゼオライト構造の安定化と結晶化を促進させる機能を有するナトリウムを用いないことによるものであると本発明者らは考えた。これにより、本発明者らは、特許文献１に記載されたナトリウムの量よりも格段に少ない量のナトリウムを含む合成ゲルを使用することで、ゼオライト膜の分離性能の低下を抑制した。 The present inventors believe that the low separation performance obtained in the above gas separation is due to not using sodium having a function of promoting the stabilization and crystallization of the zeolite structure in forming the zeolite membrane. Was. As a result, the present inventors have suppressed the decrease in the separation performance of the zeolite membrane by using a synthetic gel containing sodium in a much smaller amount than the amount of sodium described in Patent Document 1.
　他方で、一定量のナトリウムが存在することでゼオライトの結晶化が促進され、ゼオライト孔以外の透過経路が減少したため、特許文献２のゼオライト膜よりも分離性能の高いゼオライト膜を得ることができた。 On the other hand, the crystallization of zeolite was promoted by the presence of a certain amount of sodium, and the permeation path other than the zeolite pores was reduced. .
　本発明において、多孔質基材とは、ゼオライト結晶を支持し得る多孔質のものであれば、液体または気体の流体の分離のために従来から用いられているいかなるものであってもよく、具体的には、アルミナ、シリカ、ジルコニア、ムライト、チタニア、炭化ケイ素、ステンレススチール等が挙げられ、特に好ましいものとしては、アルミナが挙げられる。 In the present invention, the porous substrate may be any material conventionally used for separating a liquid or gaseous fluid, as long as it can support zeolite crystals. Specifically, alumina, silica, zirconia, mullite, titania, silicon carbide, stainless steel and the like can be mentioned, and alumina is particularly preferable.
　一般的に、ゼオライトとは、沸石とも呼ばれる、アルミノケイ酸塩結晶の一種を意味する。構造中で、ケイ素およびアルミニウムは４つの酸素（酸化物イオン）に取り囲まれた正四面体型の構造単位を形成し、これが酸素を介して互いに連結することにより三次元的な骨格構造を形成する。 Zeolite generally means a kind of aluminosilicate crystals, also called zeolite. In the structure, silicon and aluminum form tetrahedral structural units surrounded by four oxygens (oxide ions), which are connected to each other via oxygen to form a three-dimensional framework structure.
　ゼオライトには、その結晶構造中に直径が数百ｐｍ程度の細孔が存在する。このようなゼオライト構造中に存在する細孔は、所定の分子程度の寸法を有し、かつ分子を吸着する性質を有し、特に細孔径よりも小さい分子を吸着しかつ通過させ、細孔径よりも大きい分子を通過させないので、細孔を利用して大きさや形状の異なる分子をふるい分けすることができる。 Zeolite has pores having a diameter of about several hundred pm in its crystal structure. The pores present in such a zeolite structure have a size of about a predetermined molecule, and have a property of adsorbing molecules, and in particular, adsorb and pass molecules smaller than the pore diameter, and Since large molecules are not allowed to pass through, molecules having different sizes and shapes can be sieved using the pores.
　ゼオライトはその種類に応じて異なった細孔のサイズを有することが知られている。ゼオライトの骨格元素であるケイ素の原子直径は、酸素のそれに比べて小さいので、細孔のサイズは、酸素数で表すのが通例になっており、「員環」が一般に用いられている。具体的には、ｎ員環は、ｎ個の酸素を含む環構造の細孔を表している。ゼオライトが備えるべき細孔の大きさは、分離対象となる分子の大きさに応じて決められる。本発明においては、炭化水素を分離対象として想定しており、この点で、本発明の分離膜を構成するゼオライトは、これを分離するために、１０員環の細孔を有することが想定され、好ましいものとして挙げられる。 It is known that zeolite has different pore sizes depending on its type. Since the atomic diameter of silicon, which is a skeletal element of zeolite, is smaller than that of oxygen, the size of pores is usually represented by the number of oxygen, and a “member ring” is generally used. Specifically, the n-membered ring represents a pore having a ring structure containing n oxygen atoms. The size of the pores that the zeolite should have depends on the size of the molecule to be separated. In the present invention, hydrocarbons are assumed to be separated, and in this regard, it is assumed that the zeolite constituting the separation membrane of the present invention has pores of a 10-membered ring in order to separate the zeolite. Are preferred.
　また、ゼオライトは、一般に多種の構造を有していることが知られており、これらを分類するために構造型が規定されており、ＡＥＩ、ＡＮＡ、ＢＥＡ、ＣＤＯ、ＣＨＡ、ＤＤＲ、ＥＡＢ、ＥＲＩ、ＦＡＵ、ＦＥＲ、ＬＥＶ、ＬＴＡ、ＬＴＬ、ＭＥＬ、ＭＥＲ、ＭＦＩ、ＭＯＲ、ＭＴＷ、ＲＨＯ等が挙げられる。製造されたゼオライトがどのような構造型を有するかは、主として、使用される構造規定剤によるものである。 In addition, zeolite is generally known to have various types of structures, and a structural type is defined to classify these, and AEI, ANA, BEA, CDO, CHA, DDR, EAB, ERI , FAU, FER, LEV, LTA, LTL, MEL, MER, MFI, MOR, MTW, RHO, and the like. The structure type of the produced zeolite mainly depends on the structure directing agent used.
　本発明では、構造規定剤としてテトラプロピルアンモニウム水酸化物を用いることによりＭＦＩ型構造のゼオライト膜を作製することができた。 で は In the present invention, a zeolite membrane having an MFI type structure could be produced by using tetrapropylammonium hydroxide as a structure directing agent.
　また、構造規定剤としては、上記のテトラプロピルアンモニウムカチオン（水酸化物）の他、テトラメチルアンモニウムカチオン、テトラエチルアンモニウムカチオン、テトラブチルアンモニウムカチオン、トリメチルアダマンチルアンモニウムカチオン等の４配位有機アンモニウムカチオンを挙げることができる。 Examples of the structure-directing agent include, in addition to the above tetrapropylammonium cation (hydroxide), a four-coordinate organic ammonium cation such as a tetramethylammonium cation, a tetraethylammonium cation, a tetrabutylammonium cation, and a trimethyladamantylammonium cation. be able to.
　ゼオライトは、上記に示したように、一般に、アルミノケイ酸塩結晶の一種であり、ケイ素およびアルミニウムを含むものであるが、ゼオライトの分子ふるいとしての機能に、ケイ素とアルミニウムの数の比が影響を及ぼす。ケイ素の割合が高いと骨格は疎水性を増し、ケイ素の割合が非常に高いゼオライトも知られているが、さらに、出発原料にアルミニウムを用いないことにより、アルミニウムを含まないゼオライトも当該業界において一般的に知られている（特開平８－２５７３０２号公報、特開２００２－１８２４７号公報）。 As described above, zeolite is generally a kind of aluminosilicate crystal and contains silicon and aluminum. The ratio of the number of silicon and aluminum affects the function of zeolite as a molecular sieve. When the proportion of silicon is high, the skeleton becomes more hydrophobic, and zeolites with a very high proportion of silicon are also known.However, zeolite containing no aluminum is commonly used in the industry because aluminum is not used as a starting material. (JP-A-8-257302 and JP-A-2002-18247).
　特定の分子の分離には、このようなアルミニウムを含まないゼオライトが便宜であり、本発明においても、このような分離膜を製造し、その効果を実証しているので、本発明において、「ゼオライト」は、アルミニウムを含まないゼオライトも包含するものとする。 For separation of a specific molecule, such an aluminum-free zeolite is convenient, and in the present invention, such a separation membrane is produced and its effect is demonstrated. "Also includes zeolites that do not contain aluminum.
　したがって、本発明において好適に使用するゼオライトは、その骨格を形成する元素として、ケイ素（Ｓｉ）および酸素（Ｏ）を含む。また、出発原料に水およびナトリウム（Ｎａ）成分を含有させることから最終的に得られるゼオライトには、水素（Ｈ）およびナトリウムが含まれることになる。この点で、本発明における好ましい分離膜の構成元素は、Ｓｉ、Ｏ、ＨおよびＮａのみである。しかし、多孔質支持管やゼオライト合成用の反応器に由来する微量の不純物元素が分離膜に含まれていても構わない。上記「のみ」は、そのような意図しない不純物が分離膜に含まれることを排除するものではない。 Therefore, the zeolite preferably used in the present invention contains silicon (Si) and oxygen (O) as elements forming the skeleton. In addition, the zeolite finally obtained from the water and sodium (Na) components contained in the starting material contains hydrogen (H) and sodium. In this regard, preferred constituent elements of the separation membrane in the present invention are only Si, O, H and Na. However, a minute amount of impurity element derived from the porous support tube or the reactor for synthesizing zeolite may be included in the separation membrane. The term “only” does not exclude that such unintended impurities are included in the separation membrane.
　本発明は、ゼオライトのＳｉ／Ｎａ２Ｏモル比が１００～６５００であること、または、Ｈ２Ｏ／Ｎａ２Ｏモル比が３５００～１０００００になるようにナトリウムを含むゼオライト製膜用反応液を用いることにより、主として気体の分離において優れた性能を有する分離膜が得られることを見出したものである。 The present invention relates to a zeolite membrane-forming reaction solution containing sodium so that the zeolite has a Si / Na 2 O molar ratio of 100 to 6500 or an H 2 O / Na 2 O molar ratio of 3500 to 100,000. It has been found that a separation membrane having excellent performance mainly in gas separation can be obtained by using the same.
　ナトリウム元素は、元素周期律分類１Ａ族のアルカリ金属であり、元素周期律表上、同族に属する元素は、同様の効果を有することは技術常識として一般に知られているところであり、したがって、Ｎａに代えて、Ｋ、Ｌｉ、Ｒｂ、Ｃｓといったアルカリ金属カチオンを用いたとしても、同様の効果、すなわち、ゼオライトの結晶化を促進させる作用が得られるであろうことは当然である。 The sodium element is an alkali metal belonging to Group 1A of the periodic table of elements, and it is generally known as common technical knowledge that elements belonging to the same group on the periodic table of the element have the same effect. Instead, even if an alkali metal cation such as K, Li, Rb, or Cs is used, a similar effect, that is, an effect of accelerating the crystallization of zeolite will be naturally obtained.
　上記のように、本発明では、ゼオライト膜を製造するためのゼオライト製膜用反応液が有するＨ２Ｏ／Ｎａ２Ｏのモル比は、３５００～１０００００の範囲内になるようにされるが、このモル比は、より好ましくは４０００～６００００の範囲内であり、さらにより好ましくは８０００～２００００の範囲内である。Ｈ２Ｏ／Ｎａ２Ｏのモル比は、ゼオライト製膜用反応液に加えられるＨ２ＯおよびＮａ２Ｏのモルから算出されて得られる値である。 As described above, in the present invention, the molar ratio of H 2 O / Na 2 O included in the zeolite membrane-forming reaction solution for producing the zeolite membrane is set to be in the range of 3500 to 100,000. This molar ratio is more preferably in the range of 4000 to 60000, and even more preferably in the range of 8000 to 20,000. The molar ratio of H 2 O / Na 2 O is a value calculated from the moles of H 2 O and Na 2 O added to the zeolite membrane-forming reaction solution.
　上記範囲内の割合でＮａ２Ｏを含むゼオライト製膜用反応液を用いて作製されるゼオライト膜におけるＳｉ／Ｎａ２Ｏのモル比は、１００～６５００の範囲内であれば、ゼオライト膜の分離性能は高いが、当該モル比は、３００～５０００の範囲内であることがより好ましく、４００～１０００の範囲内であることがさらにより好ましい。 If the molar ratio of Si / Na 2 O in the zeolite membrane prepared using the zeolite membrane-forming reaction solution containing Na 2 O in the above range is within the range of 100 to 6,500, the separation of the zeolite membrane is performed. Although the performance is high, the molar ratio is more preferably in the range of 300 to 5,000, and even more preferably in the range of 400 to 1,000.
　ここで、ゼオライト膜におけるＳｉ／Ｎａ２Ｏのモル比は、ＥＤＸ（エネルギー分散型Ｘ線分析）により測定・算出され得る。 Here, the molar ratio of Si / Na 2 O in the zeolite membrane can be measured and calculated by EDX (energy dispersive X-ray analysis).
　（分離膜の製造方法）
　本発明による分離膜は、概略的に、以下の工程（１）～（３）を実施することにより作製することができる。
（１）水、Ｎａ成分、Ｓｉ成分、および構造規定剤を混合して所定時間にわたって混合する；
（２）得られた混合物を反応器に投入し、さらに、ゼオライト結晶を支持するための多孔質基材を入れ、当該反応器内においてゼオライト結晶を成長させる；
（３）当該反応器からゼオライト結晶を支持した多孔質基材について、洗浄、乾燥、焼成する。 (Method of manufacturing separation membrane)
The separation membrane according to the present invention can be manufactured by roughly performing the following steps (1) to (3).
(1) water, Na component, Si component, and the structure directing agent are mixed and mixed for a predetermined time;
(2) charging the obtained mixture into a reactor, further adding a porous substrate for supporting zeolite crystals, and growing zeolite crystals in the reactor;
(3) The porous substrate supporting the zeolite crystals is washed, dried and fired from the reactor.
　上記の工程（１）において、水は、イオン交換水、蒸留水等であってよい。Ｎａ成分としては、水酸化ナトリウム、塩化ナトリウムが挙げられ、Ｓｉ成分としては、ケイ酸、ケイ酸塩、ヒュームドシリカ、ケイ酸エチルが挙げられる。両方を有する後述の実施例のようにＮａ含有コロイダルシリカも挙げられる。構造規定剤としては、テトラプロピルアンモニウム水酸化物が挙げられるが、上記に挙げた他のものであってもよい。 に お い て In the above step (1), the water may be ion-exchanged water, distilled water, or the like. Examples of the Na component include sodium hydroxide and sodium chloride, and examples of the Si component include silicic acid, silicate, fumed silica, and ethyl silicate. Na-containing colloidal silica may also be used, as in the examples below, which have both. Examples of the structure-directing agent include tetrapropylammonium hydroxide, but may be other ones as described above.
　混合に要する時間は、例えば、５分～２４時間であるが、特に限定されるものではない。得られた混合物は、水溶液、懸濁液、ゲル状等の形態になるが、次の合成反応に適した形態であれば、特に限定されるものではない。 時間 The time required for mixing is, for example, 5 minutes to 24 hours, but is not particularly limited. The obtained mixture is in the form of an aqueous solution, suspension, gel or the like, but is not particularly limited as long as it is in a form suitable for the next synthesis reaction.
　混合の段階であるので、温度条件、圧力条件等に限定はないが、例えば、常温および常圧でなされる。 る の で Because it is a mixing stage, there is no limitation on temperature conditions, pressure conditions, etc., for example, at normal temperature and normal pressure.
　当該混合物における、Ｈ２Ｏ／Ｎａ２Ｏのモル比は、３５００～１０００００とされる。 The molar ratio of H 2 O / Na 2 O in the mixture is 3500 to 100,000.
　次に、工程（２）において、ゼオライト合成用の反応器としては、反応中の高温高圧に耐えることのできる従来公知の種々のものから選ばれる。例えば、オートクレーブが挙げられる。ゼオライト膜合成中に撹拌することができるような設備を有していることが好ましい。 Next, in the step (2), the reactor for synthesizing the zeolite is selected from various conventionally known reactors that can withstand high temperature and high pressure during the reaction. An example is an autoclave. It is preferable to have equipment capable of stirring during the synthesis of the zeolite membrane.
　反応器内の反応条件は、例えば、温度：１００℃～２００℃、反応時間：８時間～４８時間が挙げられるが、目的とするゼオライトの膜厚に応じて適宜選択される。 反 応 The reaction conditions in the reactor include, for example, temperature: 100 ° C. to 200 ° C., and reaction time: 8 hours to 48 hours, and are appropriately selected depending on the intended zeolite film thickness.
　上記の工程（３）における、洗浄、乾燥、焼成は、従来から知られている方法により行われる。洗浄には、例えば、水（イオン交換水、蒸留水等）が用いられる。乾燥条件としては、温度：常温～１５０℃が挙げられ、乾燥には、例えば、乾燥炉が用いられる。焼成条件としては、温度：３５０～８００℃が挙げられ、焼成には、例えば、電気炉やガス炉が用いられる。 洗浄 The washing, drying and baking in the above step (3) are performed by a conventionally known method. For cleaning, for example, water (ion-exchanged water, distilled water, or the like) is used. Drying conditions include a temperature of room temperature to 150 ° C., and a drying furnace, for example, is used for drying. The firing conditions include a temperature of 350 to 800 ° C. The firing is performed using, for example, an electric furnace or a gas furnace.
　（実施例）
　以下に、本発明に合致する分離膜を具体的に作製するとともに、その効果を実証するための試験を行ったので、これらを実施例として説明する。また、実施例との比較のための本発明に合致しない分離膜を作製し、このような分離膜の効果も同様に測定したので併せて示す。以下の実施例は、本発明の分離膜の一例であり、本発明の範囲はこれらの実施例に示すものに限定されるものではない。 (Example)
Hereinafter, a separation membrane conforming to the present invention was specifically manufactured, and a test for demonstrating its effect was performed. These will be described as examples. Further, a separation membrane not conforming to the present invention for comparison with the examples was prepared, and the effect of such a separation membrane was measured in the same manner. The following examples are examples of the separation membrane of the present invention, and the scope of the present invention is not limited to those shown in these examples.
　（実施例１）
　４０％テトラプロピルアンモニウム水酸化物水溶液１．３５ｇとイオン交換水６８．７７ｇ、Ｎａ含有４０％コロイダルシリカ（ＳｉＯ２／Ｎａ２Ｏ＝１００）４．０ｇをテフロン（登録商標）内筒式のオートクレーブに加え、３０分間撹拌した。このときのＨ２Ｏ／Ｎａ２Ｏモル比は１５０００である。 (Example 1)
1.35 g of a 40% aqueous solution of tetrapropylammonium hydroxide, 68.77 g of ion-exchanged water, and 4.0 g of 40% colloidal silica containing Na (SiO 2 / Na 2 O = 100) were charged in a Teflon (registered trademark) inner autoclave. And stirred for 30 minutes. The H 2 O / Na 2 O molar ratio at this time is 15,000.
　その後、オートクレーブ内にＭＦＩ型ゼオライト結晶を塗布したアルミナ多孔質管（長さ：２８ｍｍ；外径：１６ｍｍ）を入れ、１４０℃で加熱した。２４時間経過後、オートクレーブを冷却し、アルミナ多孔質管を取り出し、イオン交換水を用いて洗浄した。その後、イオン交換水に浸漬し、洗浄を２回繰り返した。アルミナ多孔質管を乾燥させた後、４００℃で４８時間にわたって焼成することでゼオライト膜を得た。 Thereafter, an alumina porous tube (length: 28 mm; outer diameter: 16 mm) coated with the MFI zeolite crystal was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
　得られたゼオライト膜を、Ｘ線回折装置（ＸＲＤ）を用いて分析した。図１に分析結果であるＸＲＤパターンを示す。図１に示すＸＲＤパターンにおいて、ＭＦＩ構造の特徴となるピークを有するため、このゼオライト膜はＭＦＩ構造を有していることがわかった。 The obtained zeolite membrane was analyzed using an X-ray diffractometer (XRD). FIG. 1 shows an XRD pattern as an analysis result. Since the XRD pattern shown in FIG. 1 has a peak characteristic of the MFI structure, it was found that this zeolite membrane had the MFI structure.
　得られたゼオライト膜について、ＥＤＸ（エネルギー分散型Ｘ線分析）によって組成を分析したところ、Ｓｉ／Ｎａ２Ｏモル比は３０６であった。 When the composition of the obtained zeolite membrane was analyzed by EDX (energy dispersive X-ray analysis), the molar ratio of Si / Na 2 O was 306.
　得られたゼオライト膜について緻密性を評価するためにパームポロメトリー試験を行ったところ、窒素のみを供給した場合の透過度と窒素およびノルマルヘキサンを供給した場合の透過度の比が７７．８であるという結果が得られた。 A palm porometry test was performed on the obtained zeolite membrane to evaluate its compactness. As a result, the ratio of the transmittance when nitrogen alone was supplied to the transmittance when nitrogen and normal hexane were supplied was 77.8. The result was that there was.
　（実施例２）
　４０％テトラプロピルアンモニウム水酸化物水溶液１．０２ｇとイオン交換水６９．５７ｇ、Ｎａ含有４０％コロイダルシリカ（ＳｉＯ２／Ｎａ２Ｏ＝１００）３．０ｇをテフロン（登録商標）内筒式のオートクレーブに加え、３０分間撹拌した。このときのＨ２Ｏ／Ｎａ２Ｏモル比は２００００である。 (Example 2)
1.02 g of a 40% aqueous solution of tetrapropylammonium hydroxide, 69.57 g of ion-exchanged water, and 3.0 g of 40% colloidal silica containing Na (SiO 2 / Na 2 O = 100) were charged in a Teflon (registered trademark) internal autoclave. And stirred for 30 minutes. The H 2 O / Na 2 O molar ratio at this time is 20,000.
　その後、オートクレーブ内にＭＦＩ型ゼオライト結晶を塗布したアルミナ多孔質管を入れ、１４０℃で加熱した。２４時間経過後、オートクレーブを冷却し、アルミナ多孔質管を取り出し、イオン交換水を用いて洗浄した。その後、イオン交換水に浸漬し、洗浄を２回繰り返した。アルミナ多孔質管を乾燥させた後、４００℃で４８時間にわたって焼成することでゼオライト膜を得た。 Thereafter, an alumina porous tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
　得られたゼオライト膜についてＥＤＸ（エネルギー分散型Ｘ線分析）によって組成を分析したところ、Ｓｉ／Ｎａ２Ｏモル比は７９９であった。 When the composition of the obtained zeolite membrane was analyzed by EDX (energy dispersive X-ray analysis), the molar ratio of Si / Na 2 O was 799.
　実施例１と同様に、得られたゼオライト膜についてパームポロメトリー試験を行ったところ、窒素のみを供給した場合の透過度と窒素およびノルマルヘキサンを供給した場合の透過度の比が１１８．０であるという結果が得られた。 A palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1. As a result, the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 118.0. The result was that there was.
　（実施例３）
　４０％テトラプロピルアンモニウム水酸化物水溶液２．５４ｇとイオン交換水６５．９６ｇ、Ｎａ含有４０％コロイダルシリカ（ＳｉＯ２／Ｎａ２Ｏ＝１００）７．５ｇをテフロン（登録商標）内筒式のオートクレーブに加え、３０分間撹拌した。このときのＨ２Ｏ／Ｎａ２Ｏモル比は４０００である。 (Example 3)
2.54 g of a 40% tetrapropylammonium hydroxide aqueous solution, 65.96 g of ion-exchanged water, and 7.5 g of Na-containing 40% colloidal silica (SiO 2 / Na 2 O = 100) were used in a Teflon (registered trademark) inner cylinder autoclave. And stirred for 30 minutes. The H 2 O / Na 2 O molar ratio at this time is 4000.
　その後、オートクレーブ内にＭＦＩ型ゼオライト結晶を塗布したアルミナ多孔質管を入れ、１４０℃で加熱した。２４時間経過後、オートクレーブを冷却し、アルミナ多孔質管を取り出し、イオン交換水を用いて洗浄した。その後、イオン交換水に浸漬し、洗浄を２回繰り返した。アルミナ多孔質管を乾燥させた後、４００℃で４８時間にわたって焼成することでゼオライト膜を得た。 Thereafter, an alumina porous tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
　得られたゼオライト膜について、ＥＤＸ（エネルギー分散型Ｘ線分析）によって組成を分析したところ、Ｓｉ／Ｎａ２Ｏモル比は１０８であった。 When the composition of the obtained zeolite membrane was analyzed by EDX (energy dispersive X-ray analysis), the molar ratio of Si / Na 2 O was 108.
　実施例１と同様に、得られたゼオライト膜についてパームポロメトリー試験を行ったところ、窒素のみを供給した場合の透過度と窒素およびノルマルヘキサンを供給した場合の透過度の比が６２．１であるという結果が得られた。 A palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the permeability when supplying only nitrogen to the permeability when supplying nitrogen and normal hexane was 62.1. The result was that there was.
　（実施例４）
　４０％テトラプロピルアンモニウム水酸化物水溶液０．２ｇとイオン交換水７１．６８ｇ、Ｎａ含有４０％コロイダルシリカ（ＳｉＯ２／Ｎａ２Ｏ＝１００）０．３０ｇをテフロン（登録商標）内筒式のオートクレーブに加え、３０分間撹拌した。このときのＨ２Ｏ／Ｎａ２Ｏモル比は１０００００である。 (Example 4)
0.2 g of a 40% tetrapropylammonium hydroxide aqueous solution, 71.68 g of ion-exchanged water, and 0.30 g of 40% colloidal silica containing Na (SiO 2 / Na 2 O = 100) were filled in a Teflon (registered trademark) inner cylinder autoclave. And stirred for 30 minutes. The H 2 O / Na 2 O molar ratio at this time is 100,000.
　その後、オートクレーブ内にＭＦＩ型ゼオライト結晶を塗布したアルミナ多孔質管を入れ、１４０℃で加熱した。２４時間経過後、オートクレーブを冷却し、アルミナ多孔質管を取り出し、イオン交換水を用いて洗浄した。その後、イオン交換水に浸漬し、洗浄を２回繰り返した。アルミナ多孔質管を乾燥後、４００℃で４８時間焼成することでゼオライト膜を得た。 Thereafter, an alumina porous tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 140 ° C. After elapse of 24 hours, the autoclave was cooled, the alumina porous tube was taken out, and washed with ion-exchanged water. Then, it was immersed in ion-exchanged water and the washing was repeated twice. After drying the alumina porous tube, it was baked at 400 ° C. for 48 hours to obtain a zeolite membrane.
　得られたゼオライト膜について、ＥＤＸ（エネルギー分散型Ｘ線分析）によって組成を分析したところ、Ｓｉ／Ｎａ２Ｏモル比は６１１４であった。 When the composition of the obtained zeolite membrane was analyzed by EDX (energy dispersive X-ray analysis), the molar ratio of Si / Na 2 O was 6,114.
　実施例１と同様に、得られたゼオライト膜についてパームポロメトリー試験を行ったところ、窒素のみを供給した場合の透過度と窒素およびノルマルヘキサンを供給した場合の透過度の比が５６．２であるという結果が得られた。 A palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 56.2. The result was that there was.
　（比較例１）
　４０％テトラプロピルアンモニウム水酸化物水溶液３．０７ｇとイオン交換水５７．９３ｇ、エタノールを９．２１ｇ加えた後に６０℃で３０分間撹拌した。その後、テトラエチルオルトシリケート（ＴＥＯＳ）１０．４７ｇをテフロン（登録商標）内筒式のオートクレーブに加え、６０℃で２４０分間撹拌した。この時のＨ２Ｏ／Ｎａ２ＯはＮａが存在しないため、無限大である。 (Comparative Example 1)
After adding 3.07 g of 40% tetrapropylammonium hydroxide aqueous solution, 57.93 g of ion-exchanged water and 9.21 g of ethanol, the mixture was stirred at 60 ° C. for 30 minutes. Thereafter, 10.47 g of tetraethylorthosilicate (TEOS) was added to a Teflon (registered trademark) internal cylinder-type autoclave, and the mixture was stirred at 60 ° C for 240 minutes. At this time, H 2 O / Na 2 O is infinite because Na does not exist.
　その後、オートクレーブ内にＭＦＩ型ゼオライト結晶を塗布したアルミナ支持管を入れ、１００℃で加熱した。１６８時間経過後、オートクレーブを冷却し、アルミナ支持管を取り出し、イオン交換水を用いて洗浄した。アルミナ支持管を乾燥させた後、５００℃で６時間焼成することでゼオライト膜を得た。 (5) Thereafter, an alumina support tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 100 ° C. After 168 hours, the autoclave was cooled, the alumina support tube was taken out, and washed with ion-exchanged water. After drying the alumina support tube, it was calcined at 500 ° C. for 6 hours to obtain a zeolite membrane.
　このゼオライト膜のＳｉ／Ｎａ２Ｏモル比は、合成にＮａを用いていないため、無限大となる。 The molar ratio of Si / Na 2 O in this zeolite membrane is infinite because Na is not used in the synthesis.
　実施例１と同様に、得られたゼオライト膜についてパームポロメトリー試験を行ったところ、窒素のみを供給した場合の透過度と窒素およびノルマルヘキサンを供給した場合の透過度の比が１９．１であるという結果が得られた。 A palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 19.1. The result was that there was.
　（比較例２：特開平６－９９０４４号公報記載の方法に準拠）
　テトラプロピルアンモニウム臭化物１．０６ｇとイオン交換水５１．９９ｇ、３０％コロイダルシリカ８ｇをテフロン（登録商標）内筒式のオートクレーブに加え、６０分間撹拌した。この時のＨ２Ｏ／Ｎａ２Ｏモル比は１６００である。 (Comparative Example 2: Based on the method described in JP-A-6-99044)
1.06 g of tetrapropylammonium bromide, 51.99 g of ion-exchanged water, and 8 g of 30% colloidal silica were added to a Teflon (registered trademark) inner cylinder-type autoclave, followed by stirring for 60 minutes. The H 2 O / Na 2 O molar ratio at this time is 1600.
　その後、オートクレーブ内にＭＦＩ型ゼオライト結晶を塗布したアルミナ支持管を入れ、１７０℃で加熱した。４８時間経過後、オートクレーブを冷却し、アルミナ支持管を取り出し、イオン交換水を用いて洗浄した。アルミナ支持管を乾燥させた後、５００℃で６時間にわたって焼成することでゼオライト膜を得た。 (5) Thereafter, an alumina support tube coated with MFI-type zeolite crystals was placed in an autoclave and heated at 170 ° C. After a lapse of 48 hours, the autoclave was cooled, the alumina support tube was taken out, and washed with ion-exchanged water. After drying the alumina support tube, it was calcined at 500 ° C. for 6 hours to obtain a zeolite membrane.
　得られたゼオライト膜について、ＥＤＸ（エネルギー分散型Ｘ線分析）によって組成を分析したところ、Ｓｉ／Ｎａ２Ｏモル比は４２であった。 When the composition of the obtained zeolite membrane was analyzed by EDX (energy dispersive X-ray analysis), the molar ratio of Si / Na 2 O was 42.
　実施例１と同様に、得られたゼオライト膜についてパームポロメトリー試験を行ったところ、窒素のみを供給した場合の透過度と窒素およびノルマルヘキサンを供給した場合の透過度の比が２１．８であるという結果が得られた。 A palm porometry test was performed on the obtained zeolite membrane in the same manner as in Example 1, and the ratio of the transmittance when only nitrogen was supplied to the transmittance when nitrogen and normal hexane were supplied was 21.8. The result was that there was.
　（パームポロメトリー試験）
　上記の各実施例１～４および比較例１～２で得られた膜について行われたパームポロメトリー試験について説明する。 (Palm porometry test)
A description will be given of palm porometry tests performed on the membranes obtained in the above Examples 1 to 4 and Comparative Examples 1 and 2.
　本発明において、パームポロメトリー試験は、非凝縮性のガスであるＮ２ガスと、凝縮性のガスであるｎ－ヘキサンを用いて行われた。パームポロメトリー試験における透過特性は、Ｎ２単独のガスと、Ｎ２＋ｎ－ヘキサンの混合ガスの透過性の比較によって評価される。具体的には、凝縮性のガスが存在すると、これをゼオライト膜に供給すれば、凝縮性のガスがゼオライト膜のゼオライト孔のみを閉塞させることが可能である。したがって、ゼオライト孔の閉塞前（Ｎ２のみを供給した場合）と、閉塞後（非凝縮性のＮ２ガスに一定量の凝縮性ガスであるｎ－ヘキサンガスを加えたものを供給した場合）とでのガス透過性の比を取り、この透過性の比が大きくなるほど、分離性能が高いことになる。ｎ－ヘキサンは、ケルビン径０．６ｎｍに相当する相対圧力Ｐ／Ｐｓ＝０．０１で供給された。 In the present invention, the palm porometry test was performed using N 2 gas which is a non-condensable gas and n-hexane which is a condensable gas. The permeation characteristics in the palm porometry test are evaluated by comparing the permeabilities of a gas of N 2 alone and a gas mixture of N 2 + n-hexane. Specifically, if a condensable gas is present and supplied to the zeolite membrane, the condensable gas can block only the zeolite pores of the zeolite membrane. Therefore, before the blockage of the zeolite pores (when only N 2 is supplied) and after blockage (when a mixture of non-condensable N 2 gas and a certain amount of n-hexane gas as a condensable gas is supplied) The ratio of the gas permeability is calculated as follows, and the larger the ratio of the gas permeability, the higher the separation performance. n-Hexane was supplied at a relative pressure P / Ps = 0.01 corresponding to a Kelvin diameter of 0.6 nm.
　（実施例５～７）
　長さ１ｍのアルミナ多孔質管を用いた他は、実施例１と同様にしてゼオライト膜を作製した。 (Examples 5 to 7)
A zeolite membrane was prepared in the same manner as in Example 1, except that a 1 m-long alumina porous tube was used.
　また、実施例５～７では、ＳｉＯ２／Ｎａ２Ｏモル比が１００（一定）であるコロイダルシリカを用いると共に、合成ゲル中の水の量を変動させた。その結果として、Ｈ２Ｏ／Ｎａ２Ｏモル比が異なる３種の合成ゲルを調製することができ、これらの３種の合成ゲルを用いて実施例５～７のゼオライト膜を作製した。 In Examples 5 to 7, colloidal silica having a SiO 2 / Na 2 O molar ratio of 100 (constant) was used, and the amount of water in the synthesis gel was varied. As a result, three types of synthetic gels having different H 2 O / Na 2 O molar ratios could be prepared, and zeolite membranes of Examples 5 to 7 were prepared using these three types of synthetic gels.
　（実施例１～４および比較例１～２の透過性能の比較）
　実施例１～４における、合成ゲル中のＨ２Ｏ／Ｎａ２Ｏモル比、ゼオライト膜のＳｉ／Ｎａ２Ｏモル比および透過度比の関係を下記の表１にまとめる。 (Comparison of transmission performance of Examples 1-4 and Comparative Examples 1-2)
Table 1 below summarizes the relationship between the H 2 O / Na 2 O molar ratio in the synthesis gel, the Si / Na 2 O molar ratio of the zeolite membrane, and the transmittance ratio in Examples 1 to 4.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　実施例５～７における、合成ゲル中のＨ２Ｏ／Ｎａ２Ｏモル比、ゼオライト膜のＳｉ／Ｎａ２Ｏモル比および透過度比の関係を下記の表２にまとめる。 Table 2 below summarizes the relationship between the H 2 O / Na 2 O molar ratio in the synthesis gel, the Si / Na 2 O molar ratio of the zeolite membrane, and the transmittance ratio in Examples 5 to 7.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　上記の各実施例における透過度比の結果について、透過性の良否について３５の値を境界値とした。 に つ い て Regarding the result of the transmittance ratio in each of the above examples, the value of 35 was used as the boundary value for the quality of the transmittance.
　実施例１～７では、透過度比が境界値の３５より顕著に大きく、緻密性の観点から非常に良好な結果が得られたことが分かる。対して、比較例１および２では、境界値３５に達することはなく、分離性能の点で不良であることが分かる。 で は In Examples 1 to 7, the transmittance ratio was significantly larger than the boundary value of 35, and it was found that very good results were obtained from the viewpoint of denseness. On the other hand, in Comparative Examples 1 and 2, the boundary value did not reach 35, indicating that the separation performance was poor.
　より理解しやすいように、Ｈ２Ｏ／Ｎａ２Ｏモル比を横軸（Ｘ軸）とし、透過度比を縦軸（Ｙ軸）とする、これらの関係を示すグラフを作成したので、図２に示す。 To make it easier to understand, a graph showing the relationship between the H 2 O / Na 2 O molar ratio on the horizontal axis (X-axis) and the transmittance ratio on the vertical axis (Y-axis) was created. It is shown in FIG.
　また同様の目的で、Ｓｉ／Ｎａ２Ｏモル比を横軸（Ｘ軸）とし、透過度比を縦軸（Ｙ軸）とする、これらの関係を示すグラフを作成したので、図３に示す。 For the same purpose, a graph showing the relationship between the Si / Na 2 O molar ratio on the horizontal axis (X-axis) and the transmittance ratio on the vertical axis (Y-axis) was created. .
　図２および図３の双方を参照して明らかなように、長さ２８ｍｍの短尺のアルミナ多孔質管を用いた場合（実施例１～４）も、長さ１ｍの長尺のアルミナ多孔質管を用いた場合（実施例５～７）も、ほぼ同様の傾向を示していることが分かる。 As is clear from both FIGS. 2 and 3, when a short alumina porous tube having a length of 28 mm was used (Examples 1 to 4), a long alumina porous tube having a length of 1 m was used. It can be seen that the same tendency is also exhibited when using (Examples 5 to 7).
　また、図２および図３の双方で、概略単峰性の山型の経過が示されており、Ｈ２Ｏ／Ｎａ２Ｏモル比であれば、３５００～１０００００の範囲内、Ｓｉ／Ｎａ２Ｏモル比であれば、１００～６５００の範囲内で、透過度比の境界値３５より顕著に大きく、良好な性能が得られることが分かる。 2 and 3 show a substantially unimodal mountain-shaped course, and if the molar ratio of H 2 O / Na 2 O is within the range of 3500 to 100000, the Si / Na 2 If the O molar ratio is within the range of 100 to 6500, it is significantly larger than the boundary value 35 of the transmittance ratio, and it can be seen that good performance can be obtained.
　実施例１～４および比較例１～２で得られた透過度比の結果によれば、実施例２のときに透過度比が最大となっている。 According to the results of the transmittance ratios obtained in Examples 1 to 4 and Comparative Examples 1 and 2, the transmittance ratio was the highest in Example 2.
　図２中、Ｈ２Ｏ／Ｎａ２Ｏモル比が２０００より低い領域、および図３中、Ｓｉ／Ｎａ２Ｏモル比が７９９より低い領域において、これらの比が大きくなる（Ｘ軸正方向）とともに透過度比（Ｙ軸正方向）が大きくなっている。これは、Ｈ２Ｏ／Ｎａ２Ｏモル比またはＳｉ／Ｎａ２Ｏモル比が大になる、すなわち、Ｎａ量が少ないほど透過度比が大きくなっており、作製されるゼオライト膜のナトリウムの含有量が減り、疎水性が高くなるため、これが透過度比の向上に反映されたものであると考えられる。 In FIG. 2, the H 2 O / Na 2 O molar ratio is lower than 2000, and in FIG. 3, the Si / Na 2 O molar ratio is lower than 799, these ratios become large (X-axis positive direction). At the same time, the transmittance ratio (the positive direction of the Y axis) increases. This is because the molar ratio of H 2 O / Na 2 O or the molar ratio of Si / Na 2 O increases, that is, the smaller the amount of Na, the higher the transmittance ratio, and the zeolite membrane to be produced contains sodium. It is thought that this is reflected in the improvement of the transmittance ratio because the amount decreases and the hydrophobicity increases.
　他方で、図２中、Ｈ２Ｏ／Ｎａ２Ｏモル比が２０００より高い領域、および図３中、Ｓｉ／Ｎａ２Ｏモル比が７９９より高い領域において、これらの比の上昇とともに透過度比が低下している。これは、Ｈ２Ｏ／Ｎａ２Ｏモル比またはＳｉ／Ｎａ２Ｏモル比が大になる、すなわち、Ｎａ量が少ないほど透過度比が小さくなっており、結晶成長に関与するＮａ量が少なくなるために結晶成長性が悪くなる結果、ゼオライト膜中の欠陥が増え、これが透過度比の低減に反映されたものであると考えられる。 On the other hand, in the region where the molar ratio of H 2 O / Na 2 O is higher than 2000 in FIG. 2 and in the region where the molar ratio of Si / Na 2 O is higher than 799 in FIG. Is declining. This is because the molar ratio of H 2 O / Na 2 O or the molar ratio of Si / Na 2 O increases, that is, the smaller the amount of Na, the smaller the transmittance ratio, and the smaller the amount of Na involved in crystal growth. As a result, the crystal growth property deteriorates, and as a result, the number of defects in the zeolite membrane increases, which is considered to be reflected in the decrease in the transmittance ratio.
　以上に示したように、本願の特徴を有するゼオライト膜である分離膜、すなわち、Ｓｉ／Ｎａ２Ｏモル比が１００～６５００であるか、または、Ｈ２Ｏ／Ｎａ２Ｏモル比が３５００～１０００００になるようにナトリウムを含むゼオライト製膜用反応液を用いて得られるものは、気体および液体などの流体分離において高い分離性能を有するものである。 As described above, the separation membrane which is a zeolite membrane having the characteristics of the present invention, that is, the molar ratio of Si / Na 2 O is 100 to 6500, or the molar ratio of H 2 O / Na 2 O is 3500 to A product obtained by using a zeolite membrane-forming reaction solution containing sodium so as to have a concentration of 100,000 has high separation performance in separating fluids such as gas and liquid.
　本願の分離膜は、例えば、液体の分離では、水－有機溶媒の分離に適用可能である。また、気体の分離では、水素－トルエンのような炭化水素よりも小さい分子の選択的な分離やノルマルブタンとイソブタンといった直鎖状炭化水素と分枝状炭化水素との分離に用いられる。 分離 The separation membrane of the present application is applicable to, for example, separation of water-organic solvent in separation of liquid. In gas separation, it is used for selective separation of molecules smaller than hydrocarbons such as hydrogen-toluene and for separation of linear hydrocarbons and branched hydrocarbons such as normal butane and isobutane.
　次に、本発明による分離膜を用いて直鎖状炭化水素と分枝状炭化水素との分離する試験を実際に行ったので以下に説明する。 (4) Next, a test for actually separating a linear hydrocarbon and a branched hydrocarbon using the separation membrane according to the present invention was conducted, and will be described below.
　（試験例）
　本試験例では、実施例６および７に記載されたようにして調製されたゼオライト膜を用いてノルマルブタン／イソブタンを分離する試験を行った。 (Test example)
In this test example, a test was conducted in which normal butane / isobutane was separated using the zeolite membrane prepared as described in Examples 6 and 7.
　本分離試験において、ゼオライト膜について有効膜長：２ｃｍに調整し、分離装置に装着した。 分離 In this separation test, the effective membrane length of the zeolite membrane was adjusted to 2 cm, and the zeolite membrane was attached to the separation device.
　分離装置の供給側には、ｎ－ブタン：イソブタンの混合ガスを供給した。この混合ガスにおけるｎ－ブタン：イソブタンのモル比は５３：４７とした。このモル比は、ガスクロマトグラフ装置（SHIMADZU製）を用いて測定したものである。また、供給ガスの温度を１５０℃、圧力を０．１ＭＰａ（Ａ）となるように調整した。 Ｎ A mixed gas of n-butane: isobutane was supplied to the supply side of the separation device. The molar ratio of n-butane: isobutane in this mixed gas was 53:47. This molar ratio was measured using a gas chromatograph (manufactured by SHIMADZU). The temperature of the supply gas was adjusted to 150 ° C. and the pressure was adjusted to 0.1 MPa (A).
　ゼオライト膜の透過側にはヘリウムガスを流通させた。透過側の温度を室温、圧力を０．１ＭＰａ（Ａ）となるように調整した。 Helium gas was passed through the permeate side of the zeolite membrane. The temperature on the transmission side was adjusted to room temperature, and the pressure was adjusted to 0.1 MPa (A).
　ゼオライト膜を透過した透過側のガス組成（分離係数）については、ガスクロマトグラフ装置（SHIMADZU製）を用いて測定し、透過量についてはビュレットを使用した石鹸膜流量計を用いて測定した。 (4) The gas composition (separation coefficient) on the permeate side through the zeolite membrane was measured using a gas chromatograph (manufactured by SHIMADZU), and the permeation amount was measured using a soap membrane flow meter using a burette.
　上記により測定したところ、実施例６のゼオライト膜では、
　　透過流速：３．６ｋｇ／ｍ２・ｈ
　　分離係数：１７．４
という結果が得られた。 As measured by the above, in the zeolite membrane of Example 6,
Permeation flow rate: 3.6 kg / m 2 · h
Separation coefficient: 17.4
The result was obtained.
　同様の試験を、実施例７のゼオライト膜を用いて行ったところ、
　　透過流速：４．７ｋｇ／ｍ２・ｈ
　　分離係数：２５．６
という結果が得られた。 When a similar test was performed using the zeolite membrane of Example 7,
Permeation flow rate: 4.7 kg / m 2 · h
Separation coefficient: 25.6
The result was obtained.
　これらの結果、本発明に係る分離膜を用いれば、透過流速および分離係数の双方につき非常に良好な結果が得られることが分かった。 As a result, it was found that the use of the separation membrane according to the present invention provided very good results for both the permeation flow rate and the separation coefficient.

Claims (5)

  1. 　多孔質基材にゼオライト結晶が支持されてなる分離膜であって、
    　ゼオライトのＳｉ／Ｎａ２Ｏモル比が１００～６５００であることを特徴とする分離膜。     A separation membrane in which zeolite crystals are supported on a porous substrate,
    A separation membrane, wherein the zeolite has a Si / Na 2 O molar ratio of 100 to 6,500.
  2. 　多孔質基材にゼオライト結晶が支持されてなる分離膜であって、
    　Ｈ２Ｏ／Ｎａ２Ｏモル比が３５００～１０００００になるようにナトリウムを含むゼオライト製膜用反応液を用いて得られることを特徴とする分離膜。     A separation membrane in which zeolite crystals are supported on a porous substrate,
    A separation membrane obtained by using a zeolite membrane-forming reaction solution containing sodium so that the molar ratio of H 2 O / Na 2 O is 3500 to 100,000.
  3. 　ゼオライトは、１０員環以下の細孔を有する、請求項１または２に記載の分離膜。 3. The separation membrane according to claim 1, wherein the zeolite has pores of 10 or less ring.
  4. 　ゼオライトは、ＭＦＩ構造を有する、請求項１または２に記載の分離膜。 3. The separation membrane according to claim 1, wherein the zeolite has an MFI structure.
  5. 　ゼオライトに、Ｈ、Ｏ、ＳｉおよびＮａの元素のみが含まれる、請求項１～４のいずれか１つに記載の分離膜。 The separation membrane according to any one of claims 1 to 4, wherein the zeolite contains only the elements of H, O, Si and Na.
PCT/JP2019/017392 2018-08-02 2019-04-24 Separation membrane WO2020026542A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2018145820A JP2021181036A (en) 2018-08-02 2018-08-02 Separation membrane
JP2018-145820 2018-08-02

Publications (1)

Publication Number Publication Date
WO2020026542A1 true WO2020026542A1 (en) 2020-02-06

Family

ID=69231480

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/017392 WO2020026542A1 (en) 2018-08-02 2019-04-24 Separation membrane

Country Status (2)

Country Link
JP (1) JP2021181036A (en)
WO (1) WO2020026542A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003088735A (en) * 2001-09-17 2003-03-25 Ngk Insulators Ltd Composite zeolite laminate and its production method
JP2011115691A (en) * 2009-12-02 2011-06-16 Hitachi Zosen Corp Method for manufacturing zeolite separation membrane
JP2013226534A (en) * 2012-03-30 2013-11-07 Mitsubishi Chemicals Corp Zeolite membrane composite
JP2017136595A (en) * 2013-07-08 2017-08-10 住友電気工業株式会社 Fluid separation material

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003088735A (en) * 2001-09-17 2003-03-25 Ngk Insulators Ltd Composite zeolite laminate and its production method
JP2011115691A (en) * 2009-12-02 2011-06-16 Hitachi Zosen Corp Method for manufacturing zeolite separation membrane
JP2013226534A (en) * 2012-03-30 2013-11-07 Mitsubishi Chemicals Corp Zeolite membrane composite
JP2017136595A (en) * 2013-07-08 2017-08-10 住友電気工業株式会社 Fluid separation material

Also Published As

Publication number Publication date
JP2021181036A (en) 2021-11-25

Similar Documents

Publication Publication Date Title
JP7060042B2 (en) Method for Producing Porous Support-Zeolite Membrane Complex and Porous Support-Zeolite Membrane Complex
JP7106883B2 (en) Porous support-zeolite membrane composite, method for producing and separating RHO-type zeolite
Xu et al. Synthesis, characterization and single gas permeation properties of NaA zeolite membrane
KR20190056423A (en) Novel zeolite synthesis using fluoride source
JP6974517B2 (en) Separation membrane structure
JP2018521933A (en) Novel CIT-13 phase crystalline germanosilicate material and process for its preparation
JP6389625B2 (en) Olefin separation method and zeolite membrane composite
Zhang et al. Synthesis of silicalite-1 membranes with high ethanol permeation in ultradilute solution containing fluoride
JPWO2016084846A1 (en) Method for producing zeolite membrane structure
JP2016174996A (en) Zeolite separation membrane and separation module
US10953364B2 (en) Method for separating carbon dioxide and apparatus for separating carbon dioxide
US9944576B2 (en) Method for separating straight-chain conjugated diene
Hedlund et al. The synthesis and testing of thin film ZSM-5 catalysts
JP2005289735A (en) Zeolite membrane and its manufacturing method
JP2010180080A (en) Method for producing zeolite membrane
JP6455923B2 (en) Method for producing para-xylene
WO2020026542A1 (en) Separation membrane
JP2017213488A (en) Olefin highly purifying zeolite membrane
Salomón et al. Synthesis of a mordenite/ZSM-5/chabazite hydrophilic membrane on a tubular support. Application to the separation of a water–propanol mixture
JP2016521204A (en) Use of zeolitic material to remove mercury (+2) ions from a liquid stream
JP2006176399A (en) Phillipsite-type-zeolite membrane and its manufacturing method
JP4599144B2 (en) MARLINOITE TYPE ZEOLITE MEMBRANE AND METHOD FOR PRODUCING THE SAME
JP2015150527A (en) Zeolite membrane for amine compound separation, method of producing the same and separation method
JP2005262064A (en) Mixture separating membrane and manufacturing method therefor
JP7358827B2 (en) Method for regenerating zeolite membrane complex

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19843081

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19843081

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP