JP2012045463A - Membrane reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a membrane reactor capable of continuously operating for a long time by further excelling in acid resistance compared to a T-type zeolite membrane, and also capable of employing a wide-range reaction condition since performance does not degrade even if the water content in a reaction product becomes high.SOLUTION: The membrane reactor is provided with a reactor and a separation membrane which selectively separates a component generated in the reactor therefrom. An inorganic porous support-zeolite membrane complex having a zeolite membrane on the surface of an inorganic porous support and having the SiO/AlOmolar ratio of zeolite of 10 or more is used as the separation membrane.

Description

  The present invention relates to a membrane reactor.

Conventionally, a membrane reactor comprising a reactor and a separation membrane that selectively separates components generated in the reactor from the reactor is known. In addition to the polymer membrane, an inorganic porous support-zeolite membrane composite having a zeolite membrane on the surface of the inorganic porous support has been proposed as the separation membrane. Then, as an esterification reaction apparatus for continuously separating water from a reaction product by reacting an organic acid or inorganic acid with an alcohol, T-type zeolite (SiO ₂ / Al ₂ O ₃ molar ratio is usually 6 to 8). A membrane reactor used has been proposed (Patent Document 1).

  In addition, the use mode of the separation membrane is roughly divided into two. Separation when the fluid in contact with the separation membrane is liquid is called a pervaporation (PV) method, and when the fluid in contact with the separation membrane is gas The separation is called a vapor permeation (VP) method.

JP 2002-47213 A

  The object of the present invention is that, compared to a T-type zeolite membrane, it is excellent in acid resistance and can be operated continuously for a long time, and further, the performance is lowered even if the water content in the reaction product is increased. Therefore, it is to provide a membrane reactor that can employ a wide range of reaction conditions.

  As a result of various studies, the present inventors have obtained knowledge that the above object can be easily achieved by using a membrane composed of a specific zeolite crystal layer as a separation membrane, and completed the present invention. It came.

That is, the gist of the present invention is a membrane reactor comprising a reactor and a separation membrane that selectively separates components generated in the reactor from the reactor, and the inorganic porous support is used as the separation membrane. A membrane reactor comprising an inorganic porous support-zeolite membrane composite comprising a zeolite membrane on the surface and the zeolite membrane containing zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio of 10 or more Exist.

  According to the present invention, compared to a T-type zeolite membrane, it is further excellent in acid resistance and can be operated continuously for a long time. Moreover, even if the water content in the reaction product is high, the performance is lowered. Therefore, there is provided a membrane reactor that can employ a wide range of reaction conditions.

FIG. 1 is an explanatory view of an example of the membrane reactor of the present invention. FIG. 2 is an explanatory view of another example of the membrane reactor of the present invention. FIG. 3 is an explanatory view of still another example of the membrane reactor of the present invention. FIG. 4 is an explanatory view of still another example of the membrane reactor of the present invention. FIG. 5 is an explanatory view of a simple pervaporation test apparatus used for obtaining the separation performance of the separation membrane in the reference example and the application example. FIG. 6 is an XRD measurement result of the zeolite membrane described in Reference Example 2. FIG. 7 shows the XRD measurement results of the zeolite membrane described in Reference Example 5. FIG. 8 shows the XRD measurement results of the zeolite membrane described in Reference Example 6.

  First, the outline | summary of the membrane reactor of this invention is demonstrated based on FIGS. 1-4. The membrane reactor of the present invention is a membrane reactor comprising a reactor and a separation membrane that selectively separates components generated in the reactor from the reactor, and the surface of the inorganic porous support is used as the separation membrane. And an inorganic porous support-zeolite membrane composite having a zeolite membrane. The membrane reactor of the present invention is structurally divided into two types. One is an integral structure in which the separation membrane (19) is arranged inside the reactor (1) (FIGS. 1 and 2), and the other is that the separation membrane is in the casing. The separation membrane module (4b) is housed and used as a separation membrane module (4b), and the separation membrane module (4b) is connected to the downstream side of the reactor (1) by piping (FIGS. 3 and 4).

  In the membrane reactor shown in FIG. 1, a separation membrane (19) is inserted from the side wall of the reactor (1). Two raw material supply valves (9) and (9) are provided on one side wall of the reactor (1), a product extraction valve (21) is provided on the other side wall, and the reactor (1) Reaction temperature control means (12) such as a heating jacket or a heater is applied to the peripheral wall. Note that one raw material supply valve may be installed depending on how the membrane reactor is used. Reference numeral (13) denotes a reaction fluid.

  The separation membrane (19) shown in FIG. 1 is an inorganic porous support-zeolite membrane composite having a zeolite membrane on the surface of a tubular inorganic porous support. These appropriate numbers (four in the illustrated example) constitute a separation membrane module (4a) having a structure fixed to the header via a flange. The header of the separation membrane module (4a) is sequentially connected to the permeate tank (10) connected to the pressure control valve (8), the cooler (2), and the vacuum pump (7) by piping. 10) A permeate discharge pump (6) is connected to the downstream.

The membrane reactor shown in FIG. 1 can be used as, for example, an esterification reaction apparatus, similarly to the invention described in JP-A-2002-47213. The organic acid or inorganic acid (A) and alcohol (B) are fed into the reactor (1) from the two raw material supply valves (9) and (9). Water (D) by-produced in the reactor (1) is withdrawn as a permeate through the separation membrane (19). And it is supplied to the permeate tank (10) through the pressure control valve (8) and the cooler (2). The water permeation flux [unit: kg / (m ² · h)] is adjusted by the heating temperature, pressure, vacuum pump (7) and pressure control valve (8) of the reactor (1). The membrane permeation driving force may employ a sweep gas system that supplies nitrogen, dry air, or the like to the permeation side instead of the vacuum system shown in FIGS. On the other hand, the organic acid or inorganic acid (A), the unreacted alcohol (B), and the product ester (C) are withdrawn from the product withdrawal valve (21). In this case, the reaction fluid (13) is a liquid, and the usage mode of the separation membrane is the PV method because the fluid contacting the separation membrane is a liquid. In practice, the product contains water that has not been separated, and this product is a product concentrate.

  The membrane reactor shown in FIG. 1 can also be applied to a method for producing dimethyl ether in which methanol is subjected to a dehydration reaction in the presence of a catalyst for producing dimethyl ether described in, for example, JP-A-2009-34666. In this case, the reactor (1) is filled with, for example, an Al—Mg-based spherical catalyst and has a pressure-resistant fixed bed reactor structure, and the temperature in the reactor (1) is the heating means (12). Therefore, it is usually kept at 250 ° C. or higher. And methanol gas is supplied in a reactor (1) from a raw material supply valve (9). Water (steam) by-produced in the reactor (1) is withdrawn through the separation membrane (19). In addition, unreacted methanol and produced dimethyl ether are extracted as vapor from the product extraction valve (21). In this case, the reaction fluid (13) is a gas, and the usage mode of the separation membrane is the VP method because the fluid in contact with the separation membrane is a gas.

  In the membrane reactor shown in FIG. 2, the inside of the reactor (1) is divided into two regions on the right and left of the reaction fluid (13) area and the permeated fluid (18) area by the partition walls of the vertically arranged separation membrane (19). It is divided into two. Two raw material supply valves (9) and (9) and a product extraction valve (21) are provided on the side wall of the reaction fluid (13) section.

  The separation membrane (19) shown in FIG. 2 is an inorganic porous support-zeolite membrane composite having a zeolite membrane on the surface of a flat inorganic porous support. The zeolite membrane is disposed on the reaction fluid (13) side, and the inorganic porous support is disposed on the permeate fluid (18) side. In the membrane reactor shown in FIG. 2, the extraction valve (16) for the permeated fluid is provided, and the pressure control valve (8) and the like are provided downstream. The meanings of the other symbols are the same as those of the membrane reactor shown in FIG. Note that the separation membrane (19) may be horizontally arranged to divide the inside of the reactor (1) into two upper and lower portions.

  The membrane reactor shown in FIG. 2 can be used as an esterification reaction apparatus as described above. That is, the organic or inorganic acid (A) and the alcohol (B) are supplied into the reaction fluid (13) through the two raw material supply valves (9) and (9). The by-product water (D) is withdrawn into the permeate fluid (18) through the separation membrane (19). The organic acid or inorganic acid (A), unreacted alcohol (B), and product ester (C) are withdrawn from the product withdrawal valve (21). The water withdrawn into the permeate fluid (18) section is supplied to the permeate tank (10) via a withdrawal valve (16), a pressure control valve (8) and a cooler (2). In this case, the reaction fluid (13) is a liquid, and the usage mode of the separation membrane is the PV method because the fluid in contact with the separation membrane is a liquid.

  In addition, the membrane reactor shown in FIG. 2 can be applied to a method for producing dimethyl ether as described above. The Al—Mg-based spherical catalyst is filled inside the zone of the reaction fluid (13). Methanol gas is supplied from the raw material supply valve (9) into the region of the reaction fluid (13). The by-product water (steam) is withdrawn into the permeate fluid (18) through the separation membrane (19). In addition, unreacted methanol and produced dimethyl ether are extracted as vapor from the product extraction valve (21). In this case, the reaction fluid (13) is a gas, and the usage mode of the separation membrane is the VP method because the fluid in contact with the separation membrane is a gas.

  In the membrane reactor shown in FIG. 3, the separation membrane (19) is accommodated in a casing and used as a separation membrane module (4b), and the separation membrane module (4b) is connected to the downstream side of the reactor (1) by piping. It is connected. The structure of the reactor (1) is basically the same as that shown in FIG. The separation membrane module (4b) shown in FIG. 3 comprises an inorganic porous support-zeolite membrane complex having a membrane made of a zeolite crystal layer on the surface of a tubular inorganic porous support as a separation membrane. The side facing the zeolite membrane is called the primary side, and the side facing the inorganic porous support is called the secondary side.

  The reactor (1) is connected by piping to the primary side of the separation membrane module (4b) through the extraction valve (16), the supply pump (5), the heater (3) and the pressure control valve (8). . And the secondary side of the separation membrane module (4b) is connected by piping to the permeate tank (10) connected to the pressure control valve (8), the cooler (2), and the vacuum pump (7) sequentially, A permeate discharge pump (6) is connected downstream of the permeate tank (10).

  On the primary side of the separation membrane module (4b), a circulation path including a circulation pump (15) and an intermediate heater (20) is sequentially provided. The circulation pump (15) and the intermediate heater (20) of the circulation path are provided. ) Are sequentially provided with a pressure control valve (8), a reflux pump (14), a return valve (17), and a branch path to the reactor (1).

  The membrane reactor shown in FIG. 3 can be used as an esterification reaction apparatus as described above. That is, the organic acid or inorganic acid (A) and alcohol (B) are supplied into the reactor (1) from the two raw material supply valves (9) and (9). The reaction fluid in the reactor (1), that is, the mixed fluid of organic acid or inorganic acid (A), unreacted alcohol (B), product ester (C), and by-product water (D), (16), supplied to the primary side of the separation membrane module (4b) via the supply pump (5), the heater (3) and the pressure control valve (8). Note that the heater (3) may not be used. Water (D) is withdrawn to the secondary side of the separation membrane module (4b) through the separation membrane (19). And it is supplied to the permeate tank (10) through the pressure control valve (8) and the cooler (2). On the other hand, the concentrated products (A, B, C) are returned to the reactor (1) through the circulation pump (15), the pressure control valve (8), the reflux pump (14), and the return valve (17). It is. Here, a part of the circulating liquid may be circulated to the primary side of the separation membrane module (4b) through a circulation path including a circulation pump (15) and an intermediate heater (20). And organic acid or inorganic acid (A), unreacted alcohol (B), and ester (C) of a product are extracted from a product extraction valve | bulb (21). In this case, the reaction fluid (13) is a liquid, and the usage mode of the separation membrane is the PV method because the fluid in contact with the separation membrane is a liquid. In addition, said branch path is provided as a preferable aspect. Therefore, the product can be extracted from a part of the circulating fluid. In this case, the product extraction valve (21) provided in the reactor (1) becomes unnecessary. In practice, the product contains water that has not been separated, and this product is a product concentrate.

  As in the membrane reactor shown in FIG. 3, the membrane reactor shown in FIG. 4 has a separation membrane (19) housed in a casing and used as a separation membrane module (4b). The separation membrane module (4b) is connected by piping. 3 is different from that of the membrane reactor shown in FIG. 3 in that (i) the evaporator (11) and the heater (3) are sequentially arranged in the pipe between the supply pump (5) and the pressure control valve (8). (Ii) The heating means (22) is provided in the separation membrane module (4b), and (iii) the pressure control valve (8) and the cooler (2) are sequentially provided on the primary side of the separation membrane module (4b). , A reflux pump (14), a return valve (17), and a branch path to the reactor (1) is provided.

  The membrane reactor shown in FIG. 4 is suitable for the VP method in which the fluid in contact with the separation membrane is a gas. For example, the usage method as an esterification reaction apparatus is as follows.

  That is, the organic acid or inorganic acid (A) and alcohol (B) are supplied into the reactor (1) from the two raw material supply valves (9) and (9). The reaction fluid in the reactor (1), that is, the mixed fluid of organic acid or inorganic acid (A), unreacted alcohol (B), product ester (C), and by-product water (D), (16), supplied to the primary side of the separation membrane module (4b) via the supply pump (5), the evaporator (11), the heater (3), and the pressure control valve (8). At this time, the reaction fluid is gasified by the evaporator (11), further heated by the heater (3), and supplied as gas. Such a gas state is maintained in the separation membrane module (4b) by the heating means (22) provided in the separation membrane module (4b). Water (D) is withdrawn to the secondary side of the separation membrane module (4b) through the separation membrane (19). And it is supplied to the permeate tank (10) through the pressure control valve (8) and the cooler (2). On the other hand, the concentrated products (A, B, C) are returned to the reactor (1) via the pressure control valve (8), the cooler (2), the reflux pump (14), and the return valve (17). It is. And organic acid or inorganic acid (A), unreacted alcohol (B), and ester (C) of a product are extracted from a product extraction valve | bulb (21).

  Although the description is omitted, the membrane reactor shown in FIG. 4 can naturally be applied to the above-described method for producing dimethyl ether (VP method).

Next, details of the separation membrane will be described. The separation membrane used in the present invention comprises an inorganic porous support-zeolite membrane composite having a zeolite membrane on the surface of the inorganic porous support as described above. The greatest feature of the present invention resides in the use of a porous support-zeolite membrane composite in which the SiO ₂ / Al ₂ O ₃ molar ratio of zeolite is 10 or more.

  First, each component which comprises the inorganic porous support body-zeolite membrane composite used by this invention is demonstrated concretely. In the following description, “inorganic porous support-zeolite membrane composite” may be simply referred to as “zeolite membrane composite”.

  The inorganic porous support used in the present invention is not particularly limited as long as it has chemical stability such that zeolite can be crystallized in the form of a film on the surface and is porous. Examples include sintered ceramics such as silica, α-alumina, γ-alumina, mullite, zirconia, titania, yttria, silicon nitride, silicon carbide, sintered metals such as iron, bronze, and stainless steel, glass, and carbon molded products. Can be mentioned.

Among inorganic porous supports, porous supports including sintered ceramics, which are solid materials whose basic components or most of them are composed of inorganic non-metallic substances, are partly zeolite. Zeolite formation during membrane synthesis is particularly preferred because it has the effect of increasing the adhesion at the interface.
Specific examples include ceramic sintered bodies containing silica, α-alumina, γ-alumina, mullite, zirconia, titania, yttria, silicon nitride, silicon carbide, and the like. Among them, the inorganic porous support containing at least one of alumina, silica, and mullite is easy to partially zeoliticize the inorganic porous support. Therefore, the inorganic porous support and zeolite, particularly CHA-type zeolite This is more preferable in that the bond becomes strong and a dense membrane with high separation performance is easily formed.

  The shape of the inorganic porous support used in the present invention is not limited as long as it can effectively separate a gas mixture or a liquid mixture. Specifically, a flat plate shape, a tubular shape, or a cylindrical shape, A honeycomb or monolith having a large number of cylindrical or prismatic holes may be mentioned, and any shape may be used.

  The inorganic porous support used in the present invention crystallizes zeolite on its surface (hereinafter also referred to as “inorganic porous support surface”).

The average pore diameter of the surface of the inorganic porous support is not particularly limited, but those having a controlled pore diameter are preferred, usually 0.02 μm or more, preferably 0.05 μm or more, more preferably 0. 0.1 μm or more, usually 20 μm or less, preferably 10 μm or less, more preferably 5 μm or less.
If the average pore diameter is too small, the amount of permeation tends to be small. If it is too large, the strength of the support itself may be insufficient, and the proportion of pores on the surface of the support will increase, forming a dense zeolite membrane. It may be difficult to be done.

The surface of the inorganic porous support is preferably smooth, and the surface may be polished with a file or the like as necessary.
The surface of the inorganic porous support means, for example, the surface of the inorganic porous support that crystallizes zeolite, and may be any surface of any shape as long as the surface is a plurality of surfaces. Also good. For example, in the case of a cylindrical tube support, it may be the outer surface or the inner surface, and in some cases both the outer and inner surfaces.

Further, the pore diameter of the portion other than the surface of the inorganic porous support of the inorganic porous support used in the present invention is not limited and need not be particularly controlled.
The porosity of the porous support is usually 20% or more, preferably 25% or more, more preferably 30% or more, and usually 70% or less, preferably 60% or less, more preferably 50% or less. The porosity of the inorganic porous support affects the permeation flow rate when separating gases and liquids, and tends to inhibit the permeation of the permeate if less than the lower limit, and the strength of the inorganic porous support if the upper limit is exceeded. Tends to decrease.

Next, a zeolite crystal having a SiO ₂ / Al ₂ O ₃ molar ratio of 10 or more will be described. The SiO ₂ / Al ₂ O ₃ molar ratio is preferably 12 or more. The upper limit is usually 2000 or less, preferably 1000 or less, more preferably 500 or less, and still more preferably 100 or less. If the SiO ₂ / Al ₂ O ₃ molar ratio is less than the lower limit, the durability tends to decrease, and if the upper limit is exceeded, the hydrophobicity is too strong and the permeation flux tends to be small. The SiO ₂ / Al ₂ O ₃ molar ratio can be adjusted by the reaction conditions of hydrothermal synthesis described later.

Incidentally, _SiO 2 / _Al 2 _{O 3} molar ratio in the present invention, a scanning electron microscope - is a value obtained by energy dispersive X-ray spectroscopy (SEM-EDX). In order to obtain information on only a film of several microns, the X-ray acceleration voltage is usually measured at 10 kV.

  The framework density of the main zeolite constituting the zeolite membrane in the present invention is not particularly limited, but is usually 17T / 1000Å or less, preferably 16T / 1000Å or less, particularly preferably 15.5T / 1000Å or less, most preferably 15T / 1000 mm or less.

The framework density means the number of T elements constituting a skeleton other than oxygen per 1000 ³ of the zeolite, and this value is determined by the structure of the zeolite. The relationship between the framework density and the structure of zeolite is shown in ATLASOF ZEOLITE FRAMEWORK TYPES Fifth Revised Edition 2001 ELSEVIER.

The main zeolite constituting the zeolite membrane in the present invention usually contains a zeolite having an oxygen 6-10 membered ring structure, and preferably contains a zeolite having an oxygen 6-8 membered ring structure.
Here, the value of n of the zeolite having an oxygen n-membered ring indicates the one having the largest number of oxygen among the pores composed of oxygen and T element forming the zeolite skeleton. For example, when there are 12-membered and 8-membered pores of oxygen, such as MOR type zeolite, it is regarded as a 12-membered ring zeolite.

  An example of a zeolite having an oxygen 6-10 membered ring structure is AEI, AEL, AFG, ANA, BRE, CAS, CDO, CHA, DAC, DDR, DOH, EAB, EPI, ESV, EUO, FAR, FRA, FER, GIS, GIU, GOO, HEU, IMF, ITE, ITH, KFI, LEV, LIO, LOS, LTN, MAR, MEP, MER, MEL, MFI, MFS, MON, MSO, MTF, MTN, MTT, MWW, NAT, NES, NON, PAU, PHI, RHO, RRO, RTE, RTH, RUT, SGT, SOD, STF, STI, STT, TER, TOL, TON, TSC, TUN, UFI, VNI, VSV, WEI, YUG, etc. There is.

  An example of a zeolite having a preferable oxygen 6-8 membered ring structure is AEI, AFG, ANA, CHA, EAB, ERI, ESV, FAR, FRA, GIS, ITE, KFI, LEV, LIO, LOS, LTN, MAR , PAU, RHO, RTH, SOD, STI, TOL, UFI, etc.

The oxygen n-membered ring structure determines the pore size of the zeolite, and in the zeolite smaller than the 6-membered ring, the pore diameter is smaller than the kinetic radius of the H ₂ O molecule, so the permeation flux is reduced and is practical. Not. Moreover, when it is larger than the oxygen 10-membered ring structure, the pore diameter becomes large, and the separation performance is lowered with a small-sized organic substance, so that the use is limited.

Among them, the zeolite structure preferably has the above-mentioned SiO ₂ / Al ₂ O ₃ molar ratio, more preferably AEI, CHA, KFI, PAU, RHO, RTH, UFI, and more preferably , CHA, LEV, UFI, most preferably CHA. The zeolite is preferably an aluminosilicate.

  Next, the CHA type zeolite will be described. The CHA-type zeolite preferably used in the present invention is a code that defines the structure of zeolite defined by International Zeolite Association (IZA) and indicates a CHA structure. It is a zeolite having a crystal structure equivalent to that of naturally occurring chabasite. The CHA-type zeolite has a structure characterized by having three-dimensional pores composed of 8-membered oxygen rings having a diameter of 3.8 × 3.8 mm, and the structure is characterized by X-ray diffraction data.

  The framework density of the CHA-type zeolite used in the present invention is 14.5 T / 1000 kg.

In the present invention, the zeolite membrane may be a zeolite alone or a membrane formed by dispersing the zeolite powder in a binder such as a polymer to form a membrane on various supports. It may be a zeolite membrane composite fixed to the surface.
Among them, a zeolite membrane composite in which the zeolite is fixed in a film form on a porous support described in detail later is particularly preferable. Since the zeolite membrane composite has a support, mechanical strength is increased, handling becomes easy, various device designs are possible, and since it is composed entirely of inorganic substances, it has excellent heat resistance and chemical resistance. It is because it is excellent.

  As a component constituting the membrane, an inorganic binder such as silica and alumina, an organic substance such as a polymer, a silylating agent for modifying the surface of the zeolite, or the like may be included as necessary in addition to zeolite.

  The zeolite membrane in the present invention may partially contain an amorphous component or the like, but is preferably a zeolite membrane substantially composed only of zeolite. Preferably, it is a zeolite membrane containing CHA-type zeolite as a main component, and may contain a part of zeolite of other structure such as mordenite type and MFI type, or may contain an amorphous component, etc. Preferably, the zeolite membrane is substantially composed of only CHA-type zeolite.

  The thickness of the zeolite membrane used in the present invention is not particularly limited, but is usually 0.1 μm or more, preferably 0.6 μm or more, more preferably 1.0 μm or more. Moreover, it is 100 micrometers or less normally, Preferably it is 60 micrometers or less, More preferably, it is the range of 20 micrometers or less. If the film thickness is too large, the amount of permeation tends to decrease, and if it is too small, the selectivity and film strength tend to decrease.

  The particle diameter of the zeolite forming the zeolite membrane in the present invention is not particularly limited, but if it is too small, the grain boundary tends to increase and the like, and the permselectivity tends to be reduced. Preferably it is 50 nm or more, More preferably, it is 100 nm or more, and an upper limit is below the thickness of a film | membrane. More preferably, the particle diameter of the zeolite is the same as the film thickness. This is because when the particle diameter of the zeolite is the same as the thickness of the membrane, the grain boundary of the zeolite is the smallest. Zeolite membranes obtained by hydrothermal synthesis are preferred because the zeolite particle size and membrane thickness may be the same.

  In the present invention, the inorganic porous support-zeolite membrane composite is one in which zeolite is fixed in the form of a membrane on the surface of the inorganic porous support, and a part of the zeolite is inside the inorganic porous support. The thing of the state which has adhered to is preferable.

  In order to form such a zeolite membrane composite, the zeolite is crystallized into a film on an inorganic porous support, and the zeolite is fixed to the inorganic porous support with an inorganic binder or an organic binder. And a method of fixing the zeolite-dispersed polymer, a method of fixing the zeolite to the inorganic porous support by impregnating a slurry of zeolite into the inorganic porous support, and optionally sucking it.

In a preferred embodiment of the present invention, zeolite is crystallized in the form of a film on the surface of the inorganic porous support.
Specifically, for example, CHA-type zeolite is crystallized in the form of a film on the surface of the inorganic porous support, and is usually crystallized in the form of a film by hydrothermal synthesis.
The position of the zeolite membrane used in the present invention on the inorganic porous support is not particularly limited. However, when a tubular inorganic porous support is used, a zeolite membrane may be attached to the outer surface or the inner surface. It may be attached to both sides depending on the system to be applied. Moreover, it may be laminated on the surface of the inorganic porous support, or may be crystallized so as to fill the pores on the surface of the porous support. In this case, it is important that there are no cracks or continuous micropores inside the crystallized film layer, and forming a so-called dense film improves the separability.

In the X-ray diffraction pattern of the inorganic porous support-zeolite membrane composite of the present invention, the peak intensity near 2θ = 17.9 ° is 0.5 times or more the peak intensity near 2θ = 20.8 °. It is preferable that it is the magnitude | size of.
The peak intensity here refers to the value obtained by subtracting the background value from the measured value. Speaking of the peak intensity ratio represented by (the intensity of the peak around 2θ = 17.9 °) / (the intensity of the peak around 2θ = 20.8 °), it is desirably 0.5 or more, preferably 1 or more. More preferably, it is 1.2 or more, Most preferably, it is 1.5 or more. The upper limit is not particularly limited, but is usually 1000 or less.

In the inorganic porous support-zeolite membrane composite of the present invention, when the zeolite membrane contains CHA type zeolite, the intensity of the peak around 2θ = 9.6 ° in the X-ray diffraction pattern is around 2θ = 20.8 °. It is preferable that it is 4 times or more the intensity of the peak.
In terms of the peak intensity ratio represented by (the intensity of the peak near 2θ = 9.6 °) / (the intensity of the peak near 2θ = 20.8 °), it is desirably 4 or more, preferably 6 or more, and more preferably. Is 8 or more, particularly preferably 10 or more. The upper limit is not particularly limited, but is usually 1000 or less.

  Here, the X-ray diffraction pattern is obtained by irradiating the surface on which zeolite is mainly attached with X-rays using CuKα as a radiation source to obtain a scanning axis of θ / 2θ. The shape of the sample to be measured may be any shape that can irradiate X-rays on the surface of the membrane composite on which the zeolite is mainly attached. The body itself or the one cut into an appropriate size restricted by the apparatus is preferable.

  The X-ray diffraction pattern here may be measured by fixing the irradiation width using an automatic variable slit when the surface of the membrane composite is a curved surface. An X-ray diffraction pattern using an automatic variable slit refers to a pattern subjected to variable → fixed slit correction.

The peak in the vicinity of 2θ = 17.9 ° here refers to the maximum one of the peaks existing in the range of 17.9 ° ± 0.6 ° among the peaks not derived from the base material, and 2θ = 20.8. The peak in the vicinity of ° indicates the maximum peak in the range of 20.8 ° ± 0.6 ° among peaks not derived from the base material.
Further, the peak near 2θ = 9.6 ° refers to the maximum peak among the peaks not derived from the base material and present in the range of 9.6 ° ± 0.6 °.

  According to the X-ray diffraction pattern, the peak near 2θ = 9.6 ° is a rhombohedral set according to COLLECTIONOF SIMULATED XRD POWTER PATTERNS FOR ZEOLITE Third Revised Edition 1996 ELSEVIER.

(No. 166), it is a peak derived from the plane having an index of (1, 0, 0) in the CHA structure.

  In addition, the peak near 2θ = 17.9 ° in the X-ray diffraction pattern is a rhombohedral group according to COLLECTIONOF SIMULATED XRD POWTER PATTERNS FOR ZEOLITE Third Revised Edition 1996 ELSEVIER.

(No. 166) is a peak derived from the (1,1,1) index in the CHA structure.

  According to the X-ray diffraction pattern, the peak near 2θ = 20.8 ° is shown in COLLECTIONOF SIMULATED XRD POWTER PATTERNS FOR ZEOLITE Third Revised Edition 1996 ELSEVERER.

(No. 166) is a peak derived from the (2, 0, -1) index in the CHA structure.

  A typical ratio of the peak intensity from the (1,0,0) plane to the peak from the (2,0, -1) plane is determined by the COLLECTION OF SIMULATEXRD POWDER PATTERNS FOR ZEOLITE Third Revised Edition 1996 ELSEVER. 2.5. Therefore, when this ratio is 4 or more, for example, the zeolite crystal is oriented so that the (1,0,0) plane when the CHA structure is rhombohedral setting is oriented almost parallel to the surface of the membrane composite. It is thought to mean growing. Orientation and growth of zeolite crystals in the zeolite membrane composite is advantageous in that a dense membrane with high separation performance can be formed.

  The typical ratio of the intensity of the peak derived from the (1,1,1) plane and the peak intensity derived from the (2,0, -1) plane is according to COLLECTION OF SIMULATEXRD POWDER patterns for ZEOLITE Third Revised Edition 1996 ELSEVIER. 0.3. Therefore, if this ratio is 0.5 or more, for example, the orientation of the zeolite crystals is such that the (1, 1, 1) plane is close to the parallel surface of the membrane composite when the CHA structure is rhombohedral setting. This means that it is growing. Orientation and growth of zeolite crystals in the zeolite membrane composite is advantageous in that a dense membrane with high separation performance can be formed.

Next, the manufacturing method of a zeolite membrane is demonstrated. The method for producing the zeolite membrane is not particularly limited as long as it can form a membrane containing zeolite. For example, (1) a method of crystallizing zeolite in a membrane form on a porous support, (2) porous support (3) A method of fixing a zeolite-dispersed polymer, (4) A porous support is impregnated with a slurry of zeolite, and in some cases, sucked Thus, any method such as a method of fixing the zeolite to the porous support can be used.
Among these, a method of crystallizing zeolite on a porous support in a film form is particularly preferable. Among these, a method of crystallizing zeolite on the surface of the inorganic porous support by placing the inorganic porous support in a reaction mixture used for zeolite production and directly hydrothermal synthesis is preferable.

  Specifically, as a method of crystallizing zeolite in the form of a membrane on the surface of the inorganic porous support, an aqueous reaction mixture that has been homogenized by adjusting the composition is loosely fixed inside the inorganic porous support. Put it in a heat and pressure resistant container such as an autoclave and heat it.

  Examples of the reaction mixture include an Si element source, an Al element source, an organic template (if necessary), and water, and an alkali source is preferably added as necessary.

The Si element source and Al element source used in the reaction mixture are not particularly limited. As the Si element source, any of amorphous silica, colloidal silica, silica gel, sodium silicate, amorphous aluminum silicate gel, tetraethoxysilane (TEOS), trimethylethoxysilane and the like can be used. As the Al element source, any of sodium aluminate, aluminum hydroxide, aluminum sulfate, aluminum nitrate, aluminum oxide, amorphous aluminosilicate gel and the like can be used.
In addition to the Al element, other element sources such as element sources such as Ga, Fe, B, Ti, Zr, Sn, and Zn may be included.

  In the production of zeolite in the present invention, an organic template (structure directing agent) can be used as necessary, and those synthesized using an organic template are preferred. This is because, when synthesized using an organic template, the ratio of silicon atoms to aluminum atoms in the crystallized zeolite is increased, and the acid resistance is improved. The organic template is not particularly limited as long as it can form a desired zeolite membrane.

  One type of template may be used, or two or more types may be used in combination. In the case of the CHA type, organic templates described in US Pat. No. 4,544,538 and US 2008/0075656 A1 may be suitably combined and used. Specifically, a cation derived from an alicyclic amine such as a cation derived from 1-adamantanamine, a cation derived from 3-quinacridinal, a cation derived from 3-exo-aminonorbornene, and the like, More preferred are cations derived from 1-adamantanamine. When a cation derived from 1-adamantanamine is used as an organic template, CHA-type zeolite capable of forming a dense film is crystallized. In addition, a CHA-type zeolite having hydrophilicity sufficient for the membrane to selectively permeate water can be formed, and a CHA-type zeolite excellent in acid resistance can be obtained.

Of the cations derived from 1-adamantanamine, the N, N, N-trialkyl-1-adamantanammonium cation is more preferred. The three alkyl groups in the case of the N, N, N-trialkyl-1-adamantanammonium cation are three independent alkyl groups, usually lower alkyl groups, preferably methyl groups. Specifically preferred is the N, N, N-trimethyl-1-adamantanammonium cation. Such cations are accompanied by anions that do not harm the formation of CHA-type zeolite. Representative examples of such anions include halogen ions such as Cl ⁻ , Br ⁻ and I ⁻ , hydroxide ions, acetates, sulfates, and carboxylates. Hydroxide ions are particularly preferably used. As other organic templates, N, N, N-trialkylbenzylammonium cations can also be used. Again, alkyl is three independent alkyls, usually lower alkyl. Preferably it is methyl. Most preferred is the N, N, N-trimethylbenzylammonium cation.

As the alkali source used in the reaction mixture, a hydroxide ion of a counter anion of an organic template, an alkali metal hydroxide such as NaOH or KOH, an alkaline earth metal hydroxide such as Ca (OH) ₂ or the like is used. it can.
The type of alkali is not particularly limited, but is usually Na, K, Li, Rb, Cs, Ca, Mg, Sr, Ba, preferably Na, K, and more preferably K. Two or more alkalis may be used in combination, and specifically, Na and K are preferably used in combination.

The ratio of the Si element source and Al element source in the reaction mixture is typically the molar ratio of the oxides of the respective _elements, sometimes referred to SiO 2 / _Al 2 _{O 3} molar ratio (hereinafter simply _SiO 2 / _Al 2 _{O 3} ratio .) The SiO ₂ / Al ₂ O ₃ ratio is 10 or more, preferably 15 or more from the viewpoint that a CHA-type zeolite membrane can be densely formed. Moreover, it is 10,000 or less normally, Preferably it is 1000 or less, More preferably, it is 300 or less, More preferably, it is 100 or less.

When the SiO ₂ / Al ₂ O ₃ ratio is within this range, a CHA-type zeolite membrane is preferable because it can be densely formed. Further, the produced CHA-type zeolite exhibits strong hydrophilicity, and is hydrophilic from a mixture containing organic matter. It is preferable at the point which can selectively permeate | transmit the compound of this, especially water. Further, a CHA-type zeolite that is strong in acid resistance and difficult to remove from Al is obtained. In addition to Al, other elements such as Ga, Fe, B, Ti, Zr, Sn, Zn and the like may be included.

When the SiO ₂ / Al ₂ O ₃ ratio is in this range, CHA-type zeolite that can form a dense film is crystallized, which is preferable. Further, it is preferable in that a CHA-type zeolite having hydrophilicity sufficient for the membrane to selectively permeate water can be produced and a CHA-type zeolite excellent in acid resistance can be obtained.

The ratio of the silica source and an organic template in the reaction mixture, the molar ratio of the organic template for SiO ₂ as (organic template / SiO ₂ ratio) is usually 0.005 or more 1 or less, preferably 0.01 or more 0.4 Hereinafter, it is more preferably 0.02 or more and 0.2 or less. In addition to being able to produce a dense CHA-type zeolite membrane within this range, the produced CHA-type zeolite has strong acid resistance and Al is not easily desorbed.

The ratio of the Si element source to the alkali source is expressed as M _{(2 / n) 2} O / SiO ₂ molar ratio when the alkali metal or alkaline earth metal is represented by M and the valence is represented by n (1 or 2). Usually, it is 0.02 or more and 0.5 or less, preferably 0.04 or more and 0.4 or less, more preferably 0.05 or more and 0.3 or less.

  Further, the case where K is contained in the alkali metal is preferable in terms of forming a denser and higher crystalline film. In this case, the molar ratio of K to all alkali metals and / or alkaline earth metals containing K is usually 0.01-1, preferably 0.1-1, and more preferably 0.3-1. is there. In addition, the addition of K can be done by changing the space group by rhomboborealsetting.

(No. 166), the peak intensity around 2θ = 9.6 °, which is a peak derived from the (1, 0, 0) index in the CHA structure, or the (1, 1, 1) surface. There is a tendency to increase the ratio of the peak intensity in the vicinity of 2θ = 17.9 ° which is the peak derived from the peak intensity in the vicinity of 2θ = 20.8 ° which is the peak derived from the (2, 0, −1) plane. is there.

The ratio of Si element source to water is usually 10 or more and 1000 or less, preferably 30 or more and 500 or less, more preferably 40 or more and 200 or less, and particularly preferably 50 or more and 150 or less, as the molar ratio of water to SiO ₂ . . When the molar ratio of the substances in the reaction mixture is within these ranges, a dense CHA-type zeolite membrane can be formed. The amount of water is particularly important in the production of a dense CHA-type zeolite membrane, and fine crystals are more likely to be produced under conditions where the amount of water is greater than that of the general powder synthesis method. There is a tendency. The amount of water when synthesizing the powdered CHA-type zeolite is generally about 15-50 as the H ₂ O / SiO ₂ molar ratio, but the H ₂ O / SiO ₂ molar ratio is high. It is preferable to use a large number of conditions. Specifically, when the conditions are 50 or more and 150 or less, the CHA-type zeolite is crystallized into a dense membrane on the surface of the inorganic porous support, and a membrane composite having high separation performance is obtained. It is preferable at the point obtained.

  Next, the manufacturing method of a composite_body | complex is demonstrated. In order to crystallize a membrane-like CHA-type zeolite that can be applied to separation of a gas or liquid mixture and can achieve a sufficient permeation flow rate on the surface of the support, the above document is simply applied as it is. However, it is not sufficient, and it is necessary to study various conditions for film formation from these methods.

  When the CHA zeolite is crystallized in the form of a film on the surface of the inorganic porous support in the present invention, the seed crystal may not be present, but the crystal of the CHA zeolite is added by adding the seed crystal in the reaction system. It is preferable in that the conversion can be promoted. There is no particular limitation on the method of adding the seed crystal, but the method of adding the seed crystal to the reaction mixture as in the synthesis of the powdered CHA-type zeolite or the method of attaching the seed crystal on the surface of the inorganic porous support. It is preferable to leave a seed crystal on the surface of the inorganic porous support as a method for producing the membrane composite. By attaching a seed crystal in advance to the surface of the support, a dense zeolite membrane with good separation performance can be easily formed.

  The seed crystal used in the present invention may be of any type as long as it is a zeolite that promotes crystallization, but is preferably a CHA-type zeolite for efficient crystallization. The CHA-type zeolite used as the seed crystal is not particularly limited, but it is desirable that the particle diameter is small, and it may be used after pulverization if necessary. Usually, it is 0.5 nm or more, preferably 1 nm or more, usually 20 μm or less, preferably 15 μm or less, more preferably 10 μm or less, and further preferably 5 μm or less.

  The method for attaching the seed crystal on the inorganic porous support in the present invention is not particularly limited, but the seed crystal is dispersed in a solvent such as water and the support is immersed in the dispersion to seed the seed crystal on the surface. There are a dipping method in which a seed crystal is adhered, and a method in which a seed crystal is mixed with a solvent such as water to form a slurry, and is coated on the surface of the inorganic porous support. The dip method is desirable for controlling the amount of seed crystals attached and producing a membrane composite with good reproducibility.

  In the present invention, the solvent in which the seed crystals are dispersed is not particularly limited, but water is preferable. The amount of the seed crystal to be dispersed is not particularly limited, but is usually 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 0.5% by weight with respect to the total weight of the dispersion. The above is preferable, usually 20% by weight or less, preferably 10% by weight or less, more preferably 5% by weight or less, still more preferably 4% by weight or less, and particularly preferably 3% by weight or less. If the amount of seed crystals to be dispersed is too small, the amount of seed crystals adhering to the inorganic porous support will be small, so there may be a part where CHA-type zeolite is not partially formed on the support surface during hydrothermal synthesis. There is a possibility of becoming a film with. If the amount of seed crystals in the dispersion is too large, the amount of seed crystals adhering to the surface of the inorganic porous support by the dipping method will be almost constant, so if too much seed crystals are dispersed, the seed crystals will be wasted. It is more disadvantageous in terms of cost.

The inorganic porous support in the present invention is preferably synthesized after a seed crystal is attached by dipping or slurry coating and then dried.
The weight of the seed crystal to be attached in advance on the surface of the support is not particularly limited, but is usually 0.01 g or more, preferably 0.05 g or more, more preferably as the weight per 1 m ^{2 of the} substrate. Is 0.1 g or more, usually 100 g or less, preferably 50 g or less, more preferably 10 g or less, and still more preferably 8 g or less. When the amount of the seed crystal is less than the lower limit, it becomes difficult to form a crystal, and when the film growth becomes insufficient or the film growth tends to be uneven, a dense film is formed. It may be difficult. If the amount of the seed crystal exceeds the upper limit, the surface irregularities are increased by the seed crystal, or the seed crystal falling from the surface of the support easily grows spontaneous nuclei, thereby inhibiting the film growth on the support. In some cases, it is difficult to form a dense film.
In the case of crystallizing by hydrothermal synthesis, when the inorganic porous support is fixed, it can take any form such as vertical placement and horizontal placement. In this case, it may be crystallized by a stationary method or may be crystallized by stirring the reaction mixture.

  The temperature at which the zeolite is crystallized is not particularly limited, but is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 150 ° C. or higher, and usually 200 ° C. or lower, preferably 190 ° C. Below, it is 180 degrees C or less more preferably. If the reaction temperature is too low, the CHA-type zeolite may be difficult to crystallize. When the reaction temperature is higher than this range, a zeolite different from the CHA type is likely to be produced.

  The heating time is not particularly limited, but is usually 1 hour or more, preferably 5 hours or more, more preferably 10 hours or more, usually 10 days or less, preferably 5 days or less, more Preferably it is 3 days or less, More preferably, it is 2 days or less. If the reaction time is too short, the CHA-type zeolite may be difficult to crystallize. If the reaction time is too long, a zeolite different from the CHA type may be easily formed.

  Although the pressure at the time of crystallization is not particularly limited, the self-generated pressure generated when the reaction mixture placed in a closed vessel is heated to this temperature range is sufficient, but an inert gas such as nitrogen is added. It doesn't matter.

The zeolite membrane composite obtained by hydrothermal synthesis is washed with water, then heated and dried. Here, the heat treatment means that the template is fired when heat is applied to dry the zeolite membrane composite or the template is used.
The temperature of the heat treatment is usually 50 ° C. or higher, preferably 80 ° C. or higher, more preferably 100 ° C. or higher, usually 200 ° C. or lower, preferably 150 ° C. or lower when drying is intended. The temperature of the heat treatment is usually 350 ° C. or higher, preferably 400 ° C. or higher, more preferably 430 ° C. or higher, more preferably 480 ° C. or higher, and usually 900 ° C. or lower, preferably 850 ° C. or lower, for the purpose of firing the template. More preferably, it is 800 ° C. or less, particularly preferably 750 ° C. or less. The heating time is not particularly limited as long as the zeolite membrane is sufficiently dried or the template is calcined, and preferably 0.5 hours or more, more Preferably it is 1 hour or more. The upper limit is not particularly limited, and is usually within 200 hours, preferably within 150 hours, and more preferably within 100 hours.
When hydrothermal synthesis is performed in the presence of an organic template, the obtained zeolite membrane composite can be washed with water, and then the organic template can be removed by, for example, heat treatment or extraction, preferably by heat treatment, that is, baking. Is appropriate.
The firing temperature is usually 350 ° C. or higher, preferably 400 ° C. or higher, more preferably 430 ° C. or higher, more preferably 480 ° C. or higher, usually 900 ° C. or lower, preferably 850 ° C. or lower, more preferably 800 ° C. or lower, particularly preferably Is 750 ° C. or lower. If the calcination temperature is too low, the proportion of the remaining organic template tends to increase, and the pores of the zeolite are small, which may reduce the permeation flux during separation and concentration. If the calcination temperature is too high, the difference in the coefficient of thermal expansion between the support and the zeolite will be large, so the zeolite membrane may be prone to cracking, and the denseness of the zeolite membrane will be lost, leading to poor separation performance. Sometimes.

  The firing time varies depending on the rate of temperature rise or the rate of temperature fall, but is not particularly limited as long as the organic template is sufficiently removed, but is preferably 1 hour or longer, more preferably 5 hours or longer. The upper limit is not particularly limited, but is, for example, usually within 200 hours, preferably within 150 hours, more preferably within 100 hours, and most preferably within 24 hours. The firing is generally performed in an air atmosphere, but can be performed in an atmosphere containing oxygen.

  It is desirable that the rate of temperature increase during firing be as slow as possible in order to reduce the difference in the thermal expansion coefficient between the support and the zeolite from causing cracks in the zeolite membrane. Usually, it is 5 ° C./min or less, preferably 2 ° C./min or less, more preferably 1 ° C./min or less, particularly preferably 0.5 ° C./min or less. Usually, it is 0.1 ° C./min or more in consideration of workability. Moreover, it is necessary to control the temperature drop rate after firing in order to avoid cracks in the zeolite membrane. Similar to the rate of temperature increase, the slower the better. Usually, it is 5 ° C./min or less, preferably 2 ° C./min or less, more preferably 1 ° C./min or less, particularly preferably 0.5 ° C./min or less. Usually, it is 0.1 ° C./min or more in consideration of workability.

The inorganic porous support-zeolite membrane composite may be ion-exchanged as necessary. When ion exchange is performed using a template, the ion exchange is usually performed after removing the template such as baking. Ions to be ion-exchanged include protons, alkali metal ions such as Na ⁺ , K ⁺ and Li ⁺ , and alkaline earth metal ions such as Ca ²⁺ , Mg ²⁺ , Sr ²⁺ and Ba ²⁺ , Fe, Cu, Zn and the like Examples thereof include transition metal ions. Of these, protons and alkali metal ions such as Na ⁺ , K ⁺ and Li ⁺ are preferred.

As an ion exchange method, the inorganic porous support-zeolite membrane complex after calcination (such as when using a template) is mixed with an aqueous solution containing an ammonium salt such as NH ₄ NO ₃ or NaNO ₃ or an ion to be exchanged. Usually, it is treated with an acid such as hydrochloric acid at a temperature of room temperature to 100 ° C., washed with water, and calcined at 200 ° C. to 500 ° C. as necessary.

  The shape of the zeolite membrane composite used in the present invention is not particularly limited, and any shape such as a tubular shape, a hollow fiber shape, a monolith type, and a honeycomb type can be adopted. Although the size is not particularly limited, for example, in the case of a tubular shape, a length of 2 cm to 200 cm, an inner diameter of 0.5 cm to 2 cm, and a thickness of 0.5 mm to 4 mm are practical and preferable.

  Next, for reference, the overall separation / concentration function of the inorganic porous support-zeolite membrane composite used in the present invention will be described. This function is achieved by bringing a gas or liquid mixture containing an organic substance into contact with one side of the support side or the zeolite membrane side through an inorganic porous support provided with a zeolite membrane, and the side on which the mixture is in contact on the opposite side. This is a function of selectively permeating a substance (a substance having a high permeability in the mixture) that is permeable to the zeolite membrane from the mixture by setting a lower pressure. Thereby, a highly permeable substance can be separated from the mixture. As a result, the specific organic substance is separated and recovered or concentrated by increasing the concentration of the specific organic substance (substance having low permeability in the mixture) in the mixture containing the organic substance. Specifically, in the case of a mixture of water and organic matter, since water is usually highly permeable to the zeolite membrane, water and organic matter are separated from the mixture, and the organic matter is concentrated in the original mixture. The separation / concentration method called pervaporation and vapor permeation is one form.

  One of the separation functions of the zeolite membrane composite used in the present invention is separation as a molecular sieve. In the case of CHA-type zeolite, gas molecules or liquid molecules having an effective pore diameter of 3.8 mm or more and those molecules It is preferably used for separation from the following gas or liquid molecules. There is no upper limit to the molecules used for separation, but the size of the molecules is usually about 100 mm or less.

Another separation function of the zeolite membrane composite used in the present invention is separation utilizing the difference in hydrophilicity. Although depending on the type of zeolite, a hydrophilic property generally appears when a certain amount of Al is contained in the zeolite framework. By controlling the crystallization conditions of the zeolite membrane, it is possible to control the SiO ₂ / Al ₂ O ₃ molar ratio in the crystal. If such a hydrophilic membrane is used, the organic matter can be separated and concentrated by selectively allowing water molecules to permeate through a mixed solution of the organic matter and water. That is, organic acids / water, alcohols / water, ketones / water such as acetone and methyl isobutyl ketone, aldehydes / water, ethers such as dioxane and tetrahydrofuran, amides such as dimethylformamide and N-methylpyrrolidone, etc. The organic substance can be separated and concentrated by selectively permeating water from a mixed aqueous solution of the organic substance and water, such as organic compounds containing nitrogen (N-containing organic substance) / water, esters such as acetate ester / water, and the like. In this case, the content of water in the mixture of the organic substance and water is not particularly limited, and the structure is broken even in a mixture having a high water content, for example, a water content of 20% by weight or more, in which the structure is broken in the A-type zeolite. High selectivity and permeation amount can be realized without any problems.
Further, in systems other than organic acid / water, even in the presence of an organic acid or an inorganic acid, it can be used because of its high acid resistance.

  Thus, the zeolite membrane composite of the present invention can realize high selectivity and permeation amount even in separation from a mixture with an organic substance having a high water content or separation under acidic conditions. Therefore, by separating the mixture usually separated by distillation using the zeolite membrane composite of the present invention, energy required for separation can be reduced as compared with distillation. Since the zeolite membrane composite of the present invention can be separated from a mixture having a wide range of water content, it can be separated even in a system that has not been possible so far. For example, since the A-type zeolite membrane could not be separated from a mixture with an organic substance having a high water content, it is necessary to concentrate the organic substance to about 90% by distillation before using the A-type zeolite membrane. there were. However, if the zeolite membrane composite of the present invention is used, water and organic matter can be separated and the organic matter can be concentrated even from a mixture with an organic matter having a high water content of, for example, 50% or more.

The membrane reactor of the present invention uses a porous support-zeolite membrane composite in which the zeolite crystal has a SiO ₂ / Al ₂ O ₃ molar ratio of 10 or more as a separation membrane. In addition, it is excellent in acid resistance and can be operated continuously for a long time.Furthermore, since the performance does not deteriorate even if the water content in the reaction product becomes high, a wide range of reaction conditions can be adopted. is there. Therefore, it can be suitably used for various reactions in which the reaction rate is increased by selectively separating the components produced in the reactor from the reactor. It can be suitably used for production of an ester in which an acid or an inorganic acid and an alcohol are reacted, production of dimethyl ether in which methanol is dehydrated in the presence of a catalyst for producing dimethyl ether.

Hereinafter, the characteristic configuration of the present invention, that is, the porous support-zeolite membrane composite in which the zeolite crystal has a SiO ₂ / Al ₂ O ₃ molar ratio of 10 or more will be specifically described based on a reference example.

-X-ray diffraction (XRD) measurement method XRD measurement was performed based on the following conditions.
Device name: X'PertPro MPD manufactured by PANalytical, the Netherlands
Optical system specifications Incident side: Enclosed X-ray tube (CuKα)
Soller Slit (0.04 rad)
Divergence Slit (Variable Slit)
Sample stage: XYZ stage
Light receiving side: Semiconductor array detector (X 'Celerator)
Ni-filter
SolarSlit (0.04 rad)
Goniometer radius: 240mm
Measurement conditions X-ray output (CuKα): 45 kV, 40 mA
Scanning axis: θ / 2θ
Scanning range (2θ): 5.0-70.0 °
Measurement mode: Continuous
Reading width: 0.05 °
Counting time: 99.7 sec
Automatic variable slit (Automatic-DS): 1 mm (irradiation width)
Lateral divergence mask: 10 mm (irradiation width)
X-rays were irradiated in a direction perpendicular to the axial direction of the cylindrical tube. Also, the X-ray is not the sample table surface, but the sample table surface, out of the two lines where the cylindrical tubular membrane complex placed on the sample table and the plane parallel to the sample table surface are in contact with each other so that noise and the like are not introduced as much as possible. It was made to hit mainly on the other line above the surface.

・ Measurement method of SEM-EDX Equipment:
SEM: FE-SEM Hitachi: S-4800
EDX: EDAX Genesis
Acceleration voltage: 10 kV
The entire field of view (25 μm × 18 μm) at a magnification of 5000 was scanned, and X-ray quantitative analysis was performed.

Reference example 1:
In order to prepare a CHA type zeolite membrane, an aqueous solution of N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) was prepared with reference to the description in USP 4,454,538. An example is shown below.
5.5 g of 1-adamantanamine (manufactured by Aldrich) was dissolved in 75 ml of methanol, 24.2 g of potassium carbonate was added, and the mixture was stirred for 30 minutes. To this, 10 ml of iodomethane was added dropwise and stirred for one day. Thereafter, 50 ml of methylene chloride was added and the solid was filtered. The solvent of the obtained solution was removed by an evaporator to obtain a solid. To this solid, 130 ml of methylene chloride was added, and filtration and removal of the solvent were repeated twice. Thereafter, the obtained solid was recrystallized using methanol, and the recrystallized solid was filtered, washed with diethyl ether, dried and dried to give N, N, N-trimethyl-1-adamantanammonium iodide (TMADI). ) Thereafter, this TMADI was dissolved in water, ion-exchanged with an anion exchange resin (SA-10A manufactured by Mitsubishi Chemical Corporation), and concentrated with an evaporator to obtain an aqueous solution of N, N, N-trimethyl-1-adamantanammonium hydroxide. By titration, the concentration of N, N, N-trimethyl-1-adamantanammonium hydroxide in this aqueous solution was 0.75 mmol / g. The amount of K contained in this aqueous solution was 1.84% by weight.

The inorganic porous support- (CHA type) zeolite membrane composite was prepared by hydrothermal synthesis of CHA type zeolite directly on the inorganic porous support.
The following was prepared as a reaction mixture for hydrothermal synthesis.
To a mixture of 6.9 g of 1 mol / L-NaOH aqueous solution and 103.6 g of water, 0.43 g of aluminum hydroxide (containing 53.5% by weight of Al ₂ O ₃ , manufactured by Aldrich) was added, stirred and dissolved, and transparent It was set as the solution. To this was added 9.2 g of the above-mentioned N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) aqueous solution (containing 0.17 g as K in the solution) as an organic template, and further colloidal. 10.4 g of silica (Snowtech-40 manufactured by Nissan Chemical Co., Ltd.) was added and stirred for 3 hours to prepare a hydrothermal synthesis mixture.

As an inorganic porous support, a mullite tube PM (external diameter: 12 mm, internal diameter: 9 mm) manufactured by Nikkato Co., Ltd. was cut to a length of 80 mm, and the outer surface was smoothed using water-resistant sandpaper. What was dried after washing with a washing machine was used. Prior to hydrothermal synthesis on the support, SiO ₂ / Al ₂ O ₃ / NaOH / H ₂ O / TMADAOH = 1 / 0.033 / 0.140 / by the dip method in the same manner as described above. A CHA-type zeolite seed crystal of about 0.5 μm, which was crystallized by hydrothermal synthesis at 160 ° C. for 2 days with a gel composition of 0.1, was attached.

The support was immersed in a dispersion of the seed crystal in about 1% by weight of water for a predetermined time, and then dried at 100 ° C. for 5 hours or more to adhere the seed crystal. The weight of the attached seed crystal was about 3 g / m ² . The support to which the seed crystal was attached was immersed in a Teflon (registered trademark) inner cylinder containing the reaction mixture in the vertical direction, the autoclave was sealed, and heated at 160 ° C. for 48 hours under an autogenous pressure. After the elapse of a predetermined time, after cooling, the support-zeolite membrane composite was taken out of the reaction mixture, washed, and dried at 100 ° C. for 5 hours or more. After drying, seal one end of the cylindrical tubular membrane composite in a state of zeolite before template firing (hereinafter sometimes referred to as as-made), and connect the other end to a vacuum line to reduce the pressure inside the tube. When the amount of air permeation was measured with a flow meter installed in a vacuum line, the amount of permeation was 0 ml / (m ² · min).
The zeolite (as-made) membrane composite before template firing was fired in an electric furnace at 550 ° C. for 10 hours. At this time, the rate of temperature increase and the rate of temperature decrease were both 0.5 ° C./min. From the difference between the weight of the membrane composite after firing and the weight of the support, the weight of the CHA-type zeolite crystallized on the support was 120 g / m ² . From SEM observation, the film thickness was about 15 μm.

  When XRD of the produced membrane was measured, it was found that CHA-type zeolite was produced. XRD measurement was performed under the above conditions. The irradiation width is fixed to 1 mm by an automatic variable slit, and XRD pattern is converted by variable slit → fixed slit conversion using XRD analysis software JADE 7.5.2 (Japanese version) of MaterialsData, Inc. Obtained. (Intensity of peak near 2θ = 17.9 °) / (Intensity of peak near 2θ = 20.8 °) = 2.9, and orientation to the (1,1,1) plane in rhombohedral setting is estimated It was done.

Moreover, as a result of observing the inorganic porous support-CHA type zeolite membrane composite cut into strips by SEM, crystals were densely formed on the surface.
Further, by SEM-EDX, was measured _SiO 2 / _Al 2 _{O 3} molar ratio of the zeolite membrane was 22.
Reference example 2:
The inorganic porous support CHA-type zeolite membrane composite was prepared by hydrothermal synthesis of CHA-type zeolite directly on the inorganic porous support.

The following was prepared as a reaction mixture for hydrothermal synthesis.
A mixture of 10.5 g of 1 mol / L-NaOH aqueous solution, 7.0 g of 1 mol / L-KOH aqueous solution and 100.0 g of water was mixed with aluminum hydroxide (containing 53.5% by weight of Al ₂ O ₃ , manufactured by Aldrich). 88 g was added, stirred and dissolved to obtain a transparent solution. As an organic template, 2.95 g of an aqueous N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) solution (containing 25% by weight of TMADAOH, manufactured by Seychem) was added, and colloidal silica (Snowtech, manufactured by Nissan Chemical Co., Ltd.) was added. −40) 10.5 g was added and stirred for 2 hours to prepare a hydrothermal synthesis mixture.

As the inorganic porous support, one treated in the same manner as in Reference Example 1 was used. Prior to hydrothermal synthesis, a CHA-type zeolite seed crystal having a particle size of about 0.5 μm was deposited on the support in the same manner as in Reference Example 1. The weight of the attached seed crystal was about 5 g / m ² .
As in Reference Example 1, the support on which the seed crystal was adhered was immersed vertically in a Teflon (registered trademark) inner cylinder containing the reaction mixture, and the autoclave was sealed, and the autoclave was sealed at 160 ° C. for 48 hours under an autogenous pressure. And heated. After the elapse of a predetermined time, after cooling, the support-zeolite membrane composite was taken out of the reaction mixture, washed, and dried at 100 ° C. for 5 hours or more. Seal one end of the cylindrical tubular membrane composite in an as-made state after drying, and connect the other end to a vacuum line to reduce the pressure inside the tube. When measured, the permeation amount was 0 ml / (m ² · min). The zeolite membrane composite before template firing was fired in an electric furnace at 500 ° C. for 5 hours. From the difference between the weight of the membrane composite after firing and the weight of the support, the weight of the CHA-type zeolite crystallized on the support was 120 g / m ² . From SEM observation, the film thickness was about 15 μm.

  When XRD of the produced zeolite membrane was measured, it was found that CHA-type zeolite was produced. XRD measurement was performed in the same manner as in Reference Example 1. Comparison of XRD of the produced membrane and XRD of SSZ-13 which is a powdered CHA type zeolite (zeolite generally referred to as SSZ-13 in US Pat. No. 4,544,538, hereinafter referred to as SSZ-13) used as a seed crystal. It is shown in 2. In FIG. 5, a) shows the XRD of SSZ-13, and b) shows the XRD of SSZ-13. Moreover, * in a figure is a peak derived from a support body. In the XRD of the produced film, it can be seen that the intensity of the peak in the vicinity of 2θ = 17.9 ° is significantly larger than that of SSZ-13, which is a powdered CHA-type zeolite. For the powdered CHA-type zeolite SSZ-13 (peak intensity around 2θ = 17.9 °) / (peak intensity around 2θ = 20.8 °) = 0.2, 2θ = 17.9 ° peak intensity) / (2θ = 20.8 ° peak intensity) = 12.6, and the orientation to the (1,1,1) plane in rhombohedral setting is estimated. It was.

Further, by SEM-EDX, was measured _SiO 2 / _Al 2 _{O 3} molar ratio of the zeolite membrane was 17.

Reference Example 3:
The inorganic porous support-CHA type zeolite membrane composite was prepared by hydrothermal synthesis of CHA type zeolite directly on the inorganic porous support.

The following was prepared as a reaction mixture for hydrothermal synthesis.
A mixture of 10.5 g of 1 mol / L-NaOH aqueous solution, 7.0 g of 1 mol / L-KOH aqueous solution and 100.4 g of water was mixed with aluminum hydroxide (containing 53.5% by weight of Al ₂ O ₃ , manufactured by Aldrich). 88 g was added, stirred and dissolved to obtain a transparent solution. As an organic template, 2.37 g of an aqueous solution of N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) (containing 25% by weight of TMADAOH, manufactured by Seychem) was added, and colloidal silica (Snowtech manufactured by Nissan Chemical Co., Ltd.) was added. −40) 10.5 g was added and stirred for 2 hours to prepare a hydrothermal synthesis mixture.

As the inorganic porous support, one treated in the same manner as in Reference Example 1 was used. Prior to hydrothermal synthesis, a CHA-type zeolite seed crystal having a particle size of about 2 μm was deposited on the support in the same manner as in Reference Example 1. The weight of the attached seed crystal was about 2 g / m ² . The CHA-type zeolite having a particle size of about 2 μm used for the seed crystal is an SiO ₂ / Al ₂ O ₃ solution using a 25 wt% N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) aqueous solution manufactured by Seychem. / NaOH / KOH / H ₂ O / TMADAOH = 1 / 0.066 / 0.15 / 0.1 / 100 / 0.1 gel composition hydrothermally synthesized for 2 days at 160 ° C. Filtered, washed with water and dried.
As in Reference Example 1, the support on which the seed crystal was adhered was immersed vertically in a Teflon (registered trademark) inner cylinder containing the reaction mixture, and the autoclave was sealed, and the autoclave was sealed at 160 ° C. for 48 hours under an autogenous pressure. And heated. After the elapse of a predetermined time, after cooling, the support-zeolite membrane composite was taken out of the reaction mixture, washed, and dried at 100 ° C. for 5 hours or more. Seal one end of the cylindrical tubular membrane composite in an as-made state after drying, and connect the other end to a vacuum line to reduce the pressure inside the tube. When measured, the permeation amount was 0 ml / (m ² · min). The zeolite membrane composite before template firing was fired in an electric furnace at 500 ° C. for 5 hours. From the difference between the weight of the membrane composite after firing and the weight of the support, the weight of the CHA-type zeolite crystallized on the support was 130 g / m ² .

  When XRD of the produced membrane was measured, it was found that CHA-type zeolite was produced. XRD measurement was performed in the same manner as in Reference Example 1. From the result of XRD of the formed film, it can be seen that the intensity of the peak around 2θ = 17.9 ° is remarkably high. It was (the intensity of the peak around 2θ = 17.9 °) / (the intensity of the peak around 2θ = 20.8 °) = 1.0.

Further, by SEM-EDX, was measured _SiO 2 / _Al 2 _{O 3} molar ratio of the zeolite membrane was 20.

Reference example 4:
An inorganic porous support-CHA-type zeolite membrane composite was prepared in the same manner as in Reference Example 3 except that a porous alumina tube (outer diameter 12 mm, inner diameter 9 mm) was used as the inorganic porous support.
From the result of XRD of the produced CHA-type zeolite membrane, it was found that (the intensity of the peak near 2θ = 17.9 °) / (the intensity of the peak near 2θ = 20.8 °) = 1.2. Further, by SEM-EDX, was measured _SiO 2 / _Al 2 _{O 3} molar ratio of the zeolite membrane was 17.

Reference example 5:
The inorganic porous support-CHA type zeolite membrane composite was prepared by hydrothermal synthesis of CHA type zeolite directly on the inorganic porous support.

The following was prepared as a reaction mixture for hydrothermal synthesis.
To a mixture of 32 g of 1 mol / L-NaOH aqueous solution, 48 g of 1 mol / L-KOH aqueous solution and 457 g of water, 4.0 g of aluminum hydroxide (containing 53.5% by weight of Al ₂ O ₃ , manufactured by Aldrich) was added and stirred. Dissolved to give a nearly clear solution. As an organic template, 13.5 g of an N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) aqueous solution (containing 25% by weight of TMADAOH, manufactured by Seychem) was added, and colloidal silica (Snowtech, manufactured by Nissan Chemical Co., Ltd.) was added. −40) 48 g was added and stirred for 2 hours to prepare a hydrothermal synthesis mixture.

As the inorganic porous support, one treated in the same manner as in Reference Example 1 was used. Prior to hydrothermal synthesis, the same treatment as in Reference Example 1 was performed except that a seed crystal of CHA-type zeolite having a particle size of about 2 μm was deposited on the support. The weight of the attached seed crystal was about 5 g / m ² .
As in Reference Example 1, the support to which the seed crystal was attached was immersed in a Teflon (registered trademark) inner cylinder containing the reaction mixture in the vertical direction, and the Teflon (registered trademark) inner cylinder was immersed in 1 L of stainless steel. The autoclave was put into a manufactured autoclave, and the autoclave was sealed and heated for 5 hours, and then heated at 160 ° C. for 48 hours under autogenous pressure. During the reaction, the reaction mixture was mixed with a stirring blade rotating at 200 rpm. After the elapse of a predetermined time, after cooling, the support-zeolite membrane composite was taken out of the reaction mixture, washed, and dried at 100 ° C. for 4 hours or more. Seal one end of the cylindrical tubular membrane composite in an as-made state after drying, and connect the other end to a vacuum line to reduce the pressure inside the tube. When measured, the permeation amount was 0 ml / (m ² · min). The zeolite membrane composite before template firing was fired in an electric furnace at 500 ° C. for 5 hours. From the difference between the weight of the membrane composite after firing and the weight of the support, the weight of the CHA-type zeolite crystallized on the support was 120 g / m ² .

When XRD of the produced membrane was measured, it was found that CHA-type zeolite was produced. XRD measurement was performed in the same manner as in Reference Example 1. The XRD of the produced film is shown in FIG. * In the figure is a peak derived from the support.
In the XRD of the formed film, it can be seen that the intensity of the peak in the vicinity of 2θ = 9.6 ° is significantly larger than that of SSZ-13, which is a powdered CHA-type zeolite. The intensity (peak intensity around 2θ = 9.6 °) / (peak intensity around 2θ = 20.8 °) = 6.8 of COLLECTION OF SIMULATED XRD POWTERNS FORZEOLITE Third Revised 19 The ratio of XRD of CHA of the powder of ((2θ = peak intensity around 9.6 °) / (peak intensity around 2θ = 20.8 °)) = 2.5, which is significantly higher than that of rhombohedral setting (1 , 0,0) plane was estimated, and the SiO ₂ / Al ₂ O ₃ molar ratio of the zeolite membrane was measured by SEM-EDX and found to be 17.

Reference Example 6:
The inorganic porous support-CHA type zeolite membrane composite was prepared by hydrothermal synthesis of CHA type zeolite directly on the inorganic porous support.

The following was prepared as a reaction mixture for hydrothermal synthesis.
To a mixture of 30.1 g of 1 mol / L-NaOH aqueous solution and 66.0 g of water was added 0.057 g of aluminum hydroxide (containing 53.5% by weight of Al ₂ O ₃ , manufactured by Aldrich) and dissolved by stirring. A clear solution was obtained. As an organic template, 12.7 g of an N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) aqueous solution (containing 25% by weight of TMADAOH, manufactured by Seychem) was added, and colloidal silica (Snowtech manufactured by Nissan Chemical Co., Ltd.) was added. −40) 23.6 g was added and stirred for 2 hours to prepare a hydrothermal synthesis mixture.

As the inorganic porous support, one treated in the same manner as in Reference Example 1 was used. Prior to hydrothermal synthesis, a CHA-type zeolite seed crystal of about 0.5 μm was deposited on the support in the same manner as in Reference Example 1. The weight of the attached seed crystal was about 3 g / m ² .
As in Reference Example 1, the support on which the seed crystal was adhered was immersed vertically in a Teflon (registered trademark) inner cylinder containing the reaction mixture, and the autoclave was sealed, and the autoclave was sealed at 160 ° C. for 48 hours under an autogenous pressure. And heated. After the elapse of a predetermined time, after cooling, the support-zeolite membrane composite was taken out of the reaction mixture, washed, and dried at 100 ° C. for 4 hours or more. Seal one end of the cylindrical tubular membrane composite in an as-made state after drying, and connect the other end to a vacuum line to reduce the pressure inside the tube. When measured, the permeation amount was 0 ml / (m ² · min). The zeolite membrane composite before template firing was fired in an electric furnace at 500 ° C. for 5 hours. From the difference between the weight of the membrane composite after firing and the weight of the support, the weight of the CHA zeolite crystallized on the support was 100 g / m ² .

When XRD of the produced membrane was measured, it was found that CHA-type zeolite was produced. XRD measurement was performed in the same manner as in Reference Example 1. The XRD of the resulting film is shown in FIG. * In the figure is a peak derived from the support.
In the XRD of the film formed, (peak intensity around 2θ = 9.6 °) / (peak intensity around 2θ = 20.8 °) = 1.7, (peak near 2θ = 17.9 °) Intensity) / (peak intensity around 2θ = 20.8 °) = 0.3.

Thus, none of the films produced showed a specific intensity in the XRD peak. From this, for example, it is presumed that the generated film is not oriented in any of the (1, 0, 0) plane and the (1, 1, 1) plane in rhombohedral setting.
Further, by SEM-EDX, tried to measure the _SiO 2 / _Al 2 _{O 3} molar ratio of the zeolite membrane, since the _SiO 2 / _Al 2 _{O 3} molar ratio of the reaction mixture of the starting is 500 zeolite film SiO _{Since the 2} / Al ₂ O ₃ molar ratio was also very high, an accurate value could not be obtained. Zeolite membrane SEM-EDX In _general, since the measurement limit value of SiO 2 / _Al 2 _{O 3} molar ratio is considered to be about 100, when at least _SiO 2 / _Al 2 _{O 3} molar ratio of this zeolite membrane is more than 100 Guessed.

Reference Example 1A:
Water is selectively permeated from a 70 ° C. water / acetic acid mixed solution (50/50 wt%) by the pervaporation method using the inorganic porous support-CHA type zeolite membrane composite obtained in Reference Example 1. Separation was performed.

  The apparatus shown in FIG. 4 was used for the pervaporation method. In FIG. 4, the inside of the zeolite membrane composite (105) is depressurized by the vacuum pump (109), and the pressure difference is about 1 atm with the outside where the liquid to be separated (104) is in contact. Due to this pressure difference, the permeated water in the liquid to be separated (104) permeates and permeates through the zeolite membrane composite (105). The permeated material is collected by the trap (107). On the other hand, acetic acid stays outside the zeolite membrane (105). The concentration of the liquid to be separated (104) was measured at regular intervals, and the separation factor for each time was calculated using the concentration. In FIG. 4, reference numeral (101) represents a stirrer, (102) represents a hot water bath, (103) represents a stirrer, (106) represents a Pirani gauge, and (108) represents a cold trap.

The composition analysis of the permeate collected in the trap and the liquid to be separated was performed by gas chromatography. Since it stabilizes in about 5 hours from the start of transmission, the transmission results after about 5 hours are shown.
The permeation flux was 4.0 kg / (m ² · h), the separation factor was 384, and the concentration of water in the permeate was 99.74% by weight. The measurement results are shown in Table 1.

Reference Example 2A:
Using the inorganic porous support-CHA-type zeolite membrane composite obtained in Reference Example 2 from the water / acetic acid mixed solution (50/50% by weight) at 70 ° C. by the pervaporation method in the same manner as in Example 1. Separation with selective permeation was performed.
The permeation flux was 4.8 kg / (m ² · h), the separation factor was 544, and the concentration of water in the permeate was 99.81% by weight. The measurement results are shown in Table 1.

Reference Example 3A:
Using the inorganic porous support-CHA-type zeolite membrane composite obtained in Reference Example 2 from the water / acetic acid mixed solution (50/50% by weight) at 80 ° C. by the pervaporation method in the same manner as in Example 1. Separation with selective permeation was performed.
The permeation flux was 6.0 kg / (m ² · h), the separation factor was 649, and the concentration of water in the permeate was 99.84% by weight. The measurement results are shown in Table 1.

Reference Example 4A:
Using the inorganic porous support-CHA-type zeolite membrane composite obtained in Reference Example 2 from the water / acetic acid mixed solution (10/90% by weight) at 70 ° C. by the pervaporation method in the same manner as in Example 1. Separation with selective permeation was performed.
The permeation flux was 1.4 kg / (m ² · h), the separation factor was 1411, and the concentration of water in the permeate was 99.33% by weight. The measurement results are shown in Table 1.

Reference Example 5A:
Using the inorganic porous support-CHA-type zeolite membrane composite obtained in Reference Example 3 from a water / acetic acid mixed solution (50/50% by weight) at 70 ° C. by a pervaporation method in the same manner as in Example 1. Separation with selective permeation was performed.
The permeation flux was 5.6 kg / (m ² · h), the separation factor was 230, and the concentration of water in the permeate was 99.57 wt%. The measurement results are shown in Table 1.

Reference Example 6A:
Using the inorganic porous support-CHA type zeolite membrane composite obtained in Reference Example 5 from the water / acetic acid mixed solution (50/50% by weight) at 70 ° C. by the pervaporation method as in Example 1. Separation with selective permeation was performed.
The permeation flux was 4.6 kg / (m ² · h), the separation factor was 64, and the concentration of water in the permeate was 98.46% by weight. The measurement results are shown in Table 1.

Reference Example 7A:
Using the inorganic porous support-CHA-type zeolite membrane composite obtained in Reference Example 6 from the water / acetic acid mixed solution (50/50% by weight) at 70 ° C. by the pervaporation method in the same manner as in Example 1. Separation with selective permeation was performed.
The permeation flux was 0.9 kg / (m ² · h), the separation factor was 26, and the concentration of water in the permeate was 96.30% by weight. The measurement results are shown in Table 1. Since the permeation flux, the separation factor, and the concentration of water in the permeate were stabilized in about 3 hours, this value is a value after about 3 hours.

Reference example 7:
An inorganic porous support-CHA type zeolite membrane composite was prepared in the same manner as in Reference Example 2 except that the following was prepared as a reaction mixture for hydrothermal synthesis. The reaction mixture used for the hydrothermal synthesis was a mixture of 12.9 g of 1 mol / L-NaOH aqueous solution, 8.6 g of 1 mol / L-KOH aqueous solution and 92.4 g of water, and aluminum hydroxide (Al ₂ O ₃ 53 1.16 g (containing 5% by weight, manufactured by Aldrich Co., Ltd.) was added and stirred to dissolve it to obtain a substantially transparent solution. As an organic template, N, N, N-trimethyl-1-adamantanammonium hydroxide (TMADAOH) aqueous solution 2.91 g (containing 25% by weight of TMADAOH, manufactured by Sechem Co.) was added, and 12.9 g of colloidal silica (Snowtech-40 manufactured by Nissan Chemical Co., Ltd.) was further added and stirred for 2 hours to prepare. From the difference between the weight of the obtained membrane composite after firing and the weight of the support, the weight of the CHA zeolite crystallized on the support was 150 g / m ² .
XRD measurement was performed in the same manner as in Reference Example 1.
It was (the intensity of the peak near 2θ = 9.6 °) / (the intensity of the peak near 2θ = 20.8 °) = 12.8.
Further, by SEM-EDX, was measured _SiO 2 / _Al 2 _{O 3} molar ratio of the zeolite membrane was 15.

Reference Example 8A:
Using the inorganic porous support-CHA-type zeolite membrane composite obtained in Reference Example 7 from the water / acetic acid mixed solution (50/50% by weight) at 70 ° C. by the pervaporation method in the same manner as in Example 1. Separation with selective permeation was performed. The permeation flux was 4.5 kg / (m ² · h), the separation factor was 180, and the concentration of water in the permeate was 99.43% by weight. The measurement results are shown in Table 1.

Reference Example 8:
The inorganic porous support-CHA type zeolite membrane composite was prepared by hydrothermal synthesis of CHA type zeolite directly on the inorganic porous support.
The following was prepared as a reaction mixture for hydrothermal synthesis.
To 126 g of 1 mol / L-KOH aqueous solution, 5.7 g of aluminum hydroxide (containing 53.5% by weight of Al ₂ O ₃ , manufactured by Aldrich) was added and dissolved by stirring to obtain a substantially transparent solution. To this was added 27 g of colloidal silica (Snowtech-40, Nissan Chemical Co., Ltd.) and stirred for 2 hours to prepare a mixture for hydrothermal synthesis.

As the inorganic porous support, one treated in the same manner as in Reference Example 1 was used. Prior to hydrothermal synthesis, a CHA-type zeolite seed crystal of about 0.2 μm was deposited on the support in the same manner as in Reference Example 1. The weight of the attached seed crystal was about 3 g / m ² .
The seed crystal of about 0.2 μm of CHA type zeolite was synthesized as follows. 10 g of Y-type zeolite having a SiO ₂ / Al ₂ O ₃ ratio of 7 manufactured by Catalyst Kasei Co., Ltd. was added to an aqueous solution in which 5 g of KOH was dissolved in 100 g of water, and the mixture was stirred for 2 hours. The reaction mixture was placed in a Teflon (registered trademark) inner cylinder, the autoclave was sealed, and the mixture was heated at 100 ° C. for 7 days. Then, it was allowed to cool, filtered and washed with water to obtain a CHA type zeolite.
As in Reference Example 1, the support on which this seed crystal was attached was immersed in a Teflon (registered trademark) inner cylinder containing the above reaction mixture in the vertical direction, and the autoclave was sealed. And heated. After the elapse of a predetermined time, after cooling, the support-zeolite membrane composite was taken out of the reaction mixture, washed, and dried at 100 ° C. for 4 hours or more. Seal one end of the cylindrical tubular membrane composite in an as-made state after drying, and connect the other end to a vacuum line to reduce the pressure inside the tube. When measured, the permeation amount was 0 ml / (m ² · min). From the difference between the weight of the membrane composite and the weight of the support, the weight of the CHA-type zeolite crystallized on the support was 50 g / m ² .

  When XRD of the produced membrane was measured, it was found that CHA-type zeolite was produced. In the XRD of the film formed, (peak intensity near 2θ = 9.6 °) / (peak intensity near 2θ = 20.8 °) = 0.3, and (peak near 2θ = 17.9 °) Intensity) / (peak intensity around 2θ = 20.8 °) = 0.1.

Thus, none of the films produced showed a specific intensity in the XRD peak. From this, for example, it is presumed that the generated film is not oriented in any of the (1, 0, 0) plane and the (1, 1, 1) plane in rhombohedral setting.
Further, by SEM-EDX, was 6 was measured _SiO 2 / _Al 2 _{O 3} ratio of the zeolite membrane.

Reference Example 9A:
Using the inorganic porous support-CHA type zeolite membrane composite obtained in Reference Example 8, water was removed from a 70 ° C. water / acetic acid aqueous solution (50/50 wt%) by the pervaporation method in the same manner as in Example 7. A selective permeation separation was performed.

The permeation flux was 2.0 kg / (m ² · h), the separation factor was 12, and the concentration of water in the permeate was 92.28% by weight. The measurement results are shown in Table 1.

Reference Example 1B:
Using the inorganic porous support-CHA type zeolite membrane composite obtained in Reference Example 4 from a water / 2-propanol aqueous solution (30/70% by weight) at 70 ° C. by the pervaporation method in the same manner as in Reference Example 1A. Separation with selective permeation of water was performed.
The permeation flux was 7.7 kg / (m ² · h), the separation factor was 3000, and the concentration of water in the permeate was 99.92% by weight. The measurement results are shown in Table 2.

Reference Example 2B:
Using the inorganic porous support-CHA type zeolite membrane composite obtained in the same manner as in Example 2, a water / 2-propanol solution (10/90 wt. %) To selectively permeate water.
The permeation flux was 4.0 kg / (m ² · h), the separation factor was 36000, and the concentration of water in the permeate was 99.97% by weight. The measurement results are shown in Table 2.

Reference Example 3B:
Using the inorganic porous support-CHA-type zeolite membrane composite obtained in the same manner as in Reference Example 2, a 70 ° C. water / 2-propanol solution (30/70 wt.%) Was obtained by the pervaporation method as in Reference Example 1A. %) To selectively permeate water.
The permeation flux was 5.8 kg / (m ² · h), the separation factor was 31000, and the concentration of water in the permeate was 99.99 wt%. The measurement results are shown in Table 2.

Reference Example 4B:
Using the inorganic porous support-CHA type zeolite membrane composite obtained in the same manner as in Reference Example 2, a 50 / 2C water / 2-propanol solution (30/70 wt.%) Was obtained by the pervaporation method as in Reference Example 1A. %) To selectively permeate water.
The permeation flux was 2.5 kg / (m ² · h), the separation factor was 29000, and the concentration of water in the permeate was 99.99 wt%. The measurement results are shown in Table 2.

Reference Example 5B:
A water / tetrahydrofuran solution (50/50 wt%) at 50 ° C. by the pervaporation method in the same manner as in Reference Example 1A using the inorganic porous support-CHA type zeolite membrane composite obtained in the same manner as in Reference Example 2. Separation allowing selective permeation of water was performed.
The permeation flux was 3.1 kg / (m ² · h), the separation factor was 3100, and the concentration of water in the permeate was 99.97% by weight. The measurement results are shown in Table 2.

Reference Example 6B:
Using an inorganic porous support-CHA type zeolite membrane composite obtained in the same manner as in Reference Example 2, a 40 ° C. water / acetone solution (50/50% by weight) was obtained by the pervaporation method in the same manner as in Reference Example 1A. Separation allowing selective permeation of water was performed.
The permeation flux was 1.6 kg / (m ² · h), the separation factor was 14600, and the concentration of water in the permeate was 99.99 wt%. The measurement results are shown in Table 2.

Reference Example 7B:
Using an inorganic porous support-CHA type zeolite membrane composite obtained in the same manner as in Reference Example 2, a water / N-methyl-2-pyrrolidone solution at 70 ° C. (pervaporation method) as in Reference Example 1A ( 50/50% by weight) was selectively separated through water.
The permeation flux was 5.6 kg / (m ² · h), the separation factor was 10300, and the concentration of water in the permeate was 99.99 wt%. The measurement results are shown in Table 2.

Reference Example 8B:
Using the inorganic porous support-CHA type zeolite membrane composite obtained in the same manner as in Reference Example 2, a water / ethanol solution (86/14% by weight) at 70 ° C. by the pervaporation method as in Reference Example 1A. Separation allowing selective permeation of water was performed.
The permeation flux was 1.3 kg / (m ² · h), the separation factor was 500, and the concentration of water in the permeate was 99.97% by weight. The measurement results are shown in Table 2.

Reference Example 8:
The inorganic porous support-CHA type zeolite membrane composite was prepared by hydrothermal synthesis of CHA type zeolite directly on the inorganic porous support.
The following was prepared as a reaction mixture for hydrothermal synthesis.
To 126 g of 1 mol / L-KOH aqueous solution, 5.7 g of aluminum hydroxide (containing 53.5% by weight of Al ₂ O ₃ , manufactured by Aldrich) was added and dissolved by stirring to obtain a substantially transparent solution. To this was added 27 g of colloidal silica (Snowtech-40, Nissan Chemical Co., Ltd.) and stirred for 2 hours to prepare a mixture for hydrothermal synthesis.

As the inorganic porous support, one treated in the same manner as in Reference Example 1 was used. Prior to hydrothermal synthesis, a CHA-type zeolite seed crystal of about 0.2 μm was deposited on the support in the same manner as in Example 1. The weight of the attached seed crystal was about 3 g / m ² .
The seed crystal of about 0.2 μm of CHA type zeolite was synthesized as follows. 10 g of Y-type zeolite having a SiO ₂ / Al ₂ O ₃ ratio of 7 manufactured by Catalyst Kasei Co., Ltd. was added to an aqueous solution in which 5 g of KOH was dissolved in 100 g of water, and the mixture was stirred for 2 hours. The reaction mixture was placed in a Teflon (registered trademark) inner cylinder, the autoclave was sealed, and the mixture was heated at 100 ° C. for 7 days. Then, it was allowed to cool, filtered and washed with water to obtain a CHA type zeolite.
As in Reference Example 1, the support on which this seed crystal was attached was immersed in a Teflon (registered trademark) inner cylinder containing the above reaction mixture in the vertical direction, and the autoclave was sealed. And heated. After the elapse of a predetermined time, after cooling, the support-zeolite membrane composite was taken out of the reaction mixture, washed, and dried at 100 ° C. for 4 hours or more. Seal one end of the cylindrical tubular membrane composite in an as-made state after drying, and connect the other end to a vacuum line to reduce the pressure inside the tube. When measured, the permeation amount was 0 ml / (m ² · min). From the difference between the weight of the membrane composite and the weight of the support, the weight of the CHA-type zeolite crystallized on the support was 50 g / m ² .

  When XRD of the produced membrane was measured, it was found that CHA-type zeolite was produced. In the XRD of the film formed, (peak intensity near 2θ = 9.6 °) / (peak intensity near 2θ = 20.8 °) = 0.3, and (peak near 2θ = 17.9 °) Intensity) / (peak intensity around 2θ = 20.8 °) = 0.1.

Thus, none of the films produced showed a specific intensity in the XRD peak. From this, for example, it is presumed that the generated film is not oriented in any of the (1, 0, 0) plane and the (1, 1, 1) plane in rhombohedral setting.
Further, by SEM-EDX, was 6 was measured _SiO 2 / _Al 2 _{O 3} ratio of the zeolite membrane.

Reference Example 9B:
Using the inorganic porous support-CHA type zeolite membrane composite obtained in Reference Example 8 from a water / 2-propanol aqueous solution (30/70% by weight) at 70 ° C. by the pervaporation method in the same manner as in Reference Example 1A. Separation with selective permeation of water was performed.
The permeation flux was 3.9 kg / (m ² · h), the separation factor was 21, and the concentration of water in the permeate was 90% by weight. The measurement results are shown in Table 2.

1: Reactor 2: Cooler 3: Heater 4a: Separation membrane module 4b: Separation membrane module 5: Supply pump 6: Pump for discharge 7: Vacuum pump 8: Pressure control valve 9: Raw material supply valve 10: Permeate tank 11: Evaporator 12: Reaction temperature control means 13: Reaction fluid 14: Recirculation pump 15: Circulation pump 16: Extraction valve 17: Return valve 18: Permeate fluid 19: Separation membrane 20: Intermediate heater 21: Product extraction valve 22: Heating means 101: Stirrer 102: Hot water bath 103: Stirrer 104: Liquid to be separated 105: Zeolite membrane complex 106: Pirani gauge 107: Trap for permeate collection 108: Cold trap 109: Vacuum pump

Claims (7)

A membrane reactor comprising a reactor and a separation membrane that selectively separates components generated in the reactor from the reactor, the separation membrane having a zeolite membrane on the surface of the inorganic porous support, and A membrane reactor, wherein the zeolite membrane comprises an inorganic porous support-zeolite membrane composite containing zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio of 10 or more.   The membrane reactor according to claim 1, which has a structure in which a separation membrane is arranged inside the reactor.   The membrane reactor according to claim 1, having a structure in which the separation membrane is accommodated in a casing and used as a separation membrane module, and the separation membrane module is connected to the downstream side of the reactor by piping.   In the X-ray diffraction pattern obtained when the zeolite membrane contains CHA-type zeolite crystals and the surface of the zeolite membrane is irradiated with X-rays, the peak intensity around 2θ = 17.9 ° is the peak intensity around 2θ = 20.8 °. The membrane reactor according to any one of claims 1 to 3, wherein the membrane reactor is 0.5 times or more.   In the X-ray diffraction pattern obtained by irradiating the zeolite membrane surface with X-rays when the zeolite membrane contains CHA-type zeolite crystals, the peak intensity around 2θ = 9.6 ° is the peak intensity around 2θ = 20.8 °. The membrane reactor according to any one of claims 1 to 3, wherein the membrane reactor is 4 times or more.   The X-ray diffraction pattern obtained by irradiating the zeolite membrane with X-rays has a peak intensity around 2θ = 17.9 ° of 0.5 times or more of a peak intensity around 2θ = 20.8 °. The membrane reactor in any one of -3.   The membrane reactor according to any one of claims 1 to 6, wherein the inorganic porous support contains at least one selected from the group consisting of alumina, silica and mullite.

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