JP2005262106A - Membrane reactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a membrane reactor made to have high separation performance by forming a mixture separating membrane having a titanosilicate type zeolite crystal layer on a porous support so that the mixture separating membrane can exhibit a catalysis. <P>SOLUTION: This membrane reactor is provided with: the mixture separating membrane 1 having the titanosilicate type zeolite crystal layer deposited on the porous support; a reaction vessel 9 arranged on the upstream side of the mixture separating membrane 1 for housing a reactive raw material 2; a pipeline 3 one end of which is connected to downstream side of the mixture separating membrane 1 for discharging a reaction product; and a vacuum pump 12 connected to the other end of the pipeline 3. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a membrane reactor having a mixture separation membrane in which a titanosilicate type zeolite crystal layer having a catalytic function and a separation function is deposited on a porous support.

  Conventionally, a distillation method, an adsorption method, a membrane separation method and the like are known for separation of a mixture of gas and liquid. However, among them, the distillation method requires a lot of energy to apply heat, and separation is difficult with an azeotropic mixture such as one having low heat resistance, one having a near boiling point, or water and ethanol. Further, the adsorption method has a problem that the apparatus for regenerating the adsorbent is large and requires a lot of energy.

  Membrane separation methods are expected to solve the problems in these distillation methods and adsorption methods, but membranes of membrane separation methods are made of various polymers such as cellulose acetate, silicon rubber, polystyrene, polyamide, and polyimide. However, there is a limit to the membrane performance of the polymer membrane, the separability is low, and there is a problem in that the application range is limited due to the difficulty in heat resistance and chemical resistance.

Therefore, in order to solve the problems caused by such a polymer material, in recent years, a separation membrane using zeolite, which is an inorganic material, has attracted attention. However, a membrane formed of zeolite crystals alone is difficult to use as a separation membrane because the connection between the zeolite crystals is weak and the mechanical strength is weak.
For this reason, the use in the form of zeolite supported on a porous support has been studied.
As for the zeolite membrane developed so far, for example, in Patent Document 1, as a “zeolite membrane and its production method”, an aqueous mixture containing a silica source and an alkali metal source is hydrothermally synthesized on a porous support. A silicalite-type zeolite membrane obtained in this manner is disclosed. According to the invention disclosed in Patent Document 1, an alcohol-selective separation membrane that is chemically and thermally stable, has high mechanical strength, and has a remarkably high separation factor can be obtained.

  Patent Document 2 discloses a liquid mixture separation membrane comprising an A-type zeolite membrane deposited on a porous support as a “liquid mixture separation membrane”. The invention disclosed in Patent Document 2 also has a remarkably high water permeability due to the molecular sieving ability of zeolite, as in the invention disclosed in Patent Document 1. Moreover, in the separation of the liquid mixing ratio by the pervaporation method, a practical liquid mixture separation membrane having high separation efficiency, excellent permeation stability, chemical stability, and good handling properties can be provided. .

On the other hand, a technique for including titanium in zeolite has already been developed. For example, as a synthesis example of a titanosilicate type zeolite composed of a silica source and a titanium source, Patent Document 3 discloses "improved titanosilicate catalyst, Production method and organic synthesis reaction using hydrogen peroxide as a catalyst ”, a crystalline conjugate of titanosilicate primary particles having pores of 50 to 300 angstroms, There is a disclosure relating to a titanosilicate catalyst having a distribution median of 1 μm or more.
The titanosilicate catalyst disclosed in Patent Document 3 provides titanosilicate particles having excellent handling characteristics and mechanical strength and high activity.

Further, Patent Document 4 discloses as a “zeolite laminated composite and a zeolite membrane reactor using the same” for a reaction separator obtained by forming a separation membrane composed of zeolite on a porous support having a catalytic function. Has been.
In the invention disclosed in this document, pressure loss is small, defects such as cracks are hardly generated in the separation membrane even under high temperature conditions, and high separation performance and permeation performance can be exhibited.

Japanese Patent Laid-Open No. 6-99044 JP-A-7-185275 Japanese Patent Laid-Open No. 7-100387 JP 2003-88734 A

  However, the zeolite membranes disclosed in Patent Literature 1 and Patent Literature 2 are both membranes due to the generation of cracks at the crystal grain boundaries of zeolite or the interface between the support and the crystal during the drying after the membrane formation, and the peeling of the membrane. There was a problem that defects or the like occurred and a dense product could not be obtained, resulting in poor separation performance.

  The titanosilicate catalyst disclosed in Patent Document 3 is a titanosilicate type zeolite prepared by the disclosed method, since it was originally developed as a catalyst. There was a problem that the separation performance was low even when it could not be used as a separation membrane or was obtained as a membrane.

Furthermore, in the zeolite membrane reactor disclosed in Patent Document 4, it is necessary to use a porous support composed of homogeneous zeolite, and there is a problem that the material of the support has a limiting factor. In addition, in order to give the porous support a catalytic function, it is necessary to supply the reaction raw material to the porous support side, and the conventional pervaporation apparatus as a reaction separation apparatus is not convenient to use. The separation membrane covering the substrate worked to suppress the reaction, and the efficiency of the reaction separation apparatus was not necessarily high.
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  The present invention has been made to solve the above-mentioned problems of the prior art. A separation membrane having a titanosilicate type zeolite crystal layer is formed on a porous support, and the separation membrane itself has a catalytic action. An object of the present invention is to provide a membrane reactor having high separation performance.

The present inventors have found that a membrane obtained by crystallizing titanosilicate type zeolite into a membrane on a porous support is less likely to cause defects and is useful as an excellent separation membrane having a high-performance separation function. The present invention was completed by finding out and applying this to a membrane reactor.
In the membrane reactor according to claim 1 of the present invention, in order to solve the above-mentioned problem, a mixture separation membrane having a titanosilicate type zeolite crystal layer deposited on a porous support, and this mixture separation membrane A reaction vessel for containing a reaction raw material and a pipe for sending a reaction product by connecting one end to the downstream side of the mixture separation membrane.
In such a membrane reactor, the mixture separation membrane is such that a titanosilicate type zeolite crystal layer having a catalytic function of titanium covers the porous support, so that the catalytic action directly acts on the reaction raw material.
Further, the pipe connected to the downstream side of the mixture separation membrane has an effect of guiding the separated reaction product.

Moreover, in the membrane reactor described in claim 2 of the present invention, the piping of the membrane reactor described in claim 1 is provided with a cooling unit for cooling the reaction product.
The membrane reactor according to the above-described configuration has an action of condensing a reaction product that is sent through a pipe.

In the membrane reactor described in claim 3, in the invention described in claim 1 or 2, the reaction vessel is accommodated in a thermostat whose temperature can be adjusted.
Such a membrane reactor has an effect of promoting the catalytic reaction by adjusting the temperature of the reaction vessel.

Since the membrane reactor according to claim 1 of the present invention forms a titanosilicate type zeolite membrane on a porous support, it is possible to directly act on the reaction product and to act as a catalyst. It can function to separate the reaction product.
In addition, since the titanosilicate type zeolite membrane is excellent in membrane-forming properties, it is difficult for defects to occur in the mixture separation membrane, and it is possible to maintain a high separation function.

  In particular, in the invention according to the second aspect, the vapor of the reaction product permeated by the cooling unit can be easily collected while condensing and reducing the volume.

  Furthermore, particularly in the invention described in claim 3, since the reaction vessel is accommodated in the high-temperature tank, the reaction raw material in the reaction vessel can be set to an appropriate temperature for the reaction, and the reaction can be promoted. It is possible to keep the temperature constant and allow the reaction to proceed stably.

Hereinafter, the best mode for carrying out the membrane reactor according to the present invention will be described.
The porous support constituting the mixture separation membrane of the membrane reactor in the present embodiment is particularly limited as long as it is chemically stable and porous so that titanosilicate zeolite can be crystallized into a membrane. For example, porous materials made of ceramics such as alumina, silica, zirconia, silicon nitride and silicon carbide, metals such as aluminum, silver and stainless steel, organic polymers such as polyethylene, polypropylene, polytetrafluoroethylene, polysulfone and polyimide A quality material can be used.

  The porous support preferably has an average pore size of 0.05 to 10 μm and a porosity of about 10 to 60%. Among these, an average pore diameter of 0.1 to 2 μm and a porosity of 30 to 50% are particularly preferable. Further, the shape of these porous supports may be any shape such as a flat plate shape, a tubular shape, a cylindrical shape, or a honeycomb shape having a large number of prismatic holes.

A titanosilicate type zeolite is a compound obtained by substituting a part of Si that forms a crystal lattice of crystalline SiO ₂ (silicalite) having a zeolite structure with Ti. Hydrogen peroxide is used as an oxidizing agent. It is known as an oxidation catalyst for various organic compounds. When Ti atoms are introduced into the crystal lattice, an absorption peak due to a Ti—O—Si bond is observed in the vicinity of 960 cm ^{−1 in the} infrared absorption spectrum, and a tetracoordinated Ti is present in the vicinity of 210 nm in the ultraviolet / visible absorption spectrum. Absorption based on is observed. By these measurements, substitution of Ti atoms can be confirmed.
Further, the thickness of the titanosilicate type zeolite crystal layer deposited on the porous support in the form of a film is preferably 0.1 to 500 μm, more preferably 0.5 to 100 μm.

  In addition, a titanosilicate type zeolite crystal layer can be formed on a porous support by using tetraalkylorthosilicate or colloidal silica (silica gel or sol) as a silicon source, tetraalkylorthotitanate or titanium halide as a titanium source. Compound, etc. Starting from tetraalkylammonium hydroxide as a structure-directing agent, and mixing raw materials sol or gel with distilled water and hydrogen peroxide, etc. at a predetermined ratio, and then immersing the porous support In addition, there is a method in which hydrothermal synthesis is performed at a predetermined temperature for a predetermined time, followed by baking to remove the structure directing agent.

  The tetraalkylorthosilicate used as the silicon source is not particularly limited, and examples thereof include tetramethylorthosilicate, tetraethylorthosilicate, tetrapropylorthosilicate, tetrabutylorthosilicate, tetrapentylorthosilicate, tetrahexylorthosilicate, and tetraheptyl. Examples thereof include orthosilicate, tetraoctyl orthosilicate, trimethylethyl silicate, dimethylethyl silicate, methyltriethyl silicate, dimethylpropyl silicate and the like. Of these, tetraethylorthosilicate is preferably used because of its easy availability.

  The tetraalkyl orthotitanate used as the titanium source is not particularly limited. Methyl triethyl titanate, dimethyl dipropyl titanate, and the like. Of these, tetraethyl orthotitanate and tetrabutyl orthotitanate are preferably used because of their easy availability.

  The tetraalkylammonium hydroxide used as the structure directing agent is not particularly limited, and examples thereof include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and the like, and are easily available. To tetrapropylammonium is preferably used.

When the porous support is immersed in the raw material gel, the seed crystal is supported on the support, whereby the titanosilicate zeolite crystals can be efficiently precipitated on the support. That is, it is convenient because the crystallization time of the titanosilicate zeolite can be shortened. As the seed crystal, a crystal having an average particle diameter of 500 μm or less, particularly 0.5 to 50 μm is preferable because it is easy to hold on the porous support. The amount of the seed crystal supported on the porous support is preferably 1 to 500 mg / cm ² , particularly preferably 10 to 60 mg / cm ² .

  In order to support the seed crystal on the porous support, it is preferable to disperse the seed crystal powder in a solvent, preferably water, and coat this on the porous support. T-type zeolite powder may be mixed as part of the above.

  In this manner, the titanosilicate type zeolite crystal layer is deposited on the surface of the porous support so that the thickness thereof is 0.1 to 500 μm, preferably 0.5 to 100 μm, as described above. A suitable mixture separation membrane according to the embodiment can be obtained.

In the present invention, the charged composition ratio of reaction raw materials (hereinafter, the composition ratio is expressed in molar ratio) when synthesizing a separation membrane in which a titanosilicate type zeolite crystal layer is deposited in the form of a membrane on a porous support. , SiO ₂ / TiO ₂ = 5 to 500, H ₂ O / SiO ₂ = 10 to 300, RN ⁺ / SiO ₂ = 0.05 to 1.0 (RN ⁺ represents tetraalkylammonium hydroxide), and It is preferable to adjust so that it becomes. More _{preferably, SiO 2 / TiO 2 = 20~300} , H 2 O / SiO 2 = 20~200, an RN + / SiO 2 = 0.1~0.8.

  In the present invention, the synthesis temperature when synthesizing a separation membrane in which a titanosilicate type zeolite crystal layer is deposited on a porous support by a hydrothermal synthesis method is 100 to 220 ° C, preferably 150 to 200 ° C. The synthesis time is 10 to 150 hours, preferably 16 to 30 hours. By performing the reaction once at the synthesis temperature and synthesis time, a separation membrane in which a titanosilicate type zeolite crystal layer is deposited in the form of a membrane on a porous support having high separation performance can be synthesized. At this time, the pressure can be performed by either self-pressure or under pressure, but usually it can be performed under self-pressure. It is not always necessary to stir the system, and film formation proceeds sufficiently even in a stationary state.

  The film hydrothermally synthesized in this way is sufficiently washed with water and then fired. The temperature of baking processing is 300-700 degreeC, Preferably it is 400-600 degreeC. The calcining time is not particularly limited, but the mixture in which the titanosilicate zeolite crystal layer used in the membrane reactor of the present invention is deposited in a film form by performing a calcining treatment for 1 to 50 hours, preferably 5 to 20 hours. A separation membrane can be manufactured.

The membrane reactor produced according to the present invention is active in the oxidation reaction of various organic compounds using hydrogen peroxide as an oxidizing agent, and is useful for, for example, alcohol oxidation, olefin epoxidation, and aromatic compound hydroxylation. is there.
In the present invention, hydrogen peroxide solution is used as an oxidizing agent, but this concentration is not particularly limited, and a low concentration or high concentration hydrogen peroxide solution can be used as appropriate, usually 5 to 90%, preferably 5 to 80%. % Hydrogen peroxide solution is used.

  The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to these examples. In the examples, two types of mixture separation membranes were prepared by depositing a titanosilicate type zeolite membrane on a porous support while changing the amount of titanium source such as tetrabutyl orthotitanate and the temperature and time of hydrothermal synthesis. In addition, as Comparative Example 1, a mixture separation membrane was prepared by depositing an MFI type silicalite membrane synthesized without containing titanium on a porous support.

Example 1 (Synthesis Example 1)
As starting materials, tetraethylorthosilicate (Aldrich 98%) 22.1 g, tetrabutylorthotitanate (Wako Pure Chemicals 95%) 0.78 g, tetrapropylammonium hydroxide (Tokyo Kasei 20%) 16.0 g, Raw material gel (SiO ₂ : TiO ₂ : RN ⁺ : H ₂ O = 1: 0.02: 0.17: 120 prepared using 211.5 g of water and 1 ml of hydrogen peroxide solution (30% manufactured by Wako Pure Chemical Industries, Ltd.) ) In a stainless steel pressure-resistant reaction tube equipped with a Teflon (registered trademark) inner cylinder, and a porous mullite support (length: 10 cm, average pore diameter: about 1 micron) is immersed in the tube. Time hydrothermal synthesis was performed. After completion of the reaction, the support having a film deposited on the surface was taken out, washed in water, and then baked at 500 ° C. for 10 hours.

Example 2 (Synthesis Example 2)
As starting materials tetraethylorthosilicate (Aldrich 98%) 80.34 g, tetrabutylorthotitanate (Wako Pure Chemical 95%) 3.86 g, tetrapropylammonium hydroxide (Tokyo Kasei 20%) 134.5 g, Raw material gel (SiO ₂ : TiO ₂ : RN ⁺ : H ₂ O = 1: 0.03: 0.35: 28) prepared using 81.3 g of water and 1 ml of hydrogen peroxide water (30% manufactured by Wako Pure Chemical Industries, Ltd.) ) In a stainless steel pressure-resistant reaction tube equipped with a Teflon (registered trademark) inner cylinder, and a porous mullite support (length: 10 cm, average pore diameter: about 1 micron) is immersed in the tube at a temperature of 170 ° C. Time hydrothermal synthesis was performed. After completion of the reaction, the support having a film deposited on the surface was taken out, washed in water, and then baked at 500 ° C. for 10 hours.

Comparative Example 1
As a comparative example, an MFI type silicalite film not containing a titanium source was prepared as follows. Raw material gel (SiO ₂ : RN) prepared using 22.1 g of tetraethylorthosilicate (98% made by Aldrich), 16.0 g of tetrapropylammonium hydroxide (20% made by Tokyo Kasei Co., Ltd.) and 211.5 g of water as starting materials. ⁺ : H ₂ O = 1: 0.17: 120) was charged into a stainless steel pressure-resistant reaction tube having a Teflon (registered trademark) inner cylinder, and a porous mullite support (length 10 cm, average pore diameter of about 1 micron) ) Was immersed in this, and hydrothermal synthesis was performed at a temperature of 200 ° C. for 24 hours. After completion of the reaction, the support having a film deposited on the surface was taken out, washed in water, and then baked at 500 ° C. for 10 hours.

The results of X-ray diffraction of the separation membrane in which the titanosilicate zeolite crystal layer was deposited on the porous support obtained in Example 1 will be described with reference to FIG.
1 are X-ray diffraction measurement diagrams. (1) is a crystal powder of titanosilicate zeolite, and (2) is deposited on the porous support prepared in Example 1. FIG. The titanosilicate type zeolite membrane, (3) is the MFI type silicalite membrane deposited on the porous support prepared in Comparative Example 1, and (4) is that of the porous support. The abscissa of the measurement diagram is 2 theta (θ), that is, shows the double value of the incident angle in degrees, and the ordinate shows the X-ray diffraction intensity.
In FIG. 1, the peak patterns of the X-ray diffraction patterns of (1) and (2) are in good agreement, and the peak pattern of the MFI type silicalite film containing no titanium source prepared in Comparative Example 1 I'm doing it. However, none of them agrees with (4). Therefore, all showed the crystal structure of zeolite, and it was confirmed that the titanosilicate type zeolite crystal layer was appropriately deposited also in the titanosilicate type mixture separation membrane in the present example.

Next, measurement results of infrared absorption spectra of the titanosilicate zeolite membrane of this example and the MFI zeolite membrane of the comparative example will be described with reference to FIG. (1) of FIG. 2 shows the infrared absorption spectrum measurement result of the titanosilicate type zeolite membrane according to this example, and (2) shows the infrared absorption spectrum measurement result of the MFI type zeolite membrane. The horizontal axis in FIG. 2 indicates the wave number per 1 cm, and the vertical axis indicates the transmission (transmittance).
In (1) according to this example of FIG. 2, an absorption peak due to the Ti—O—Si bond is observed in the vicinity of 960 cm ⁻¹ .

Further, FIG. 3 is a diagram showing the results of measuring the diffuse reflection spectrum in the ultraviolet / visible region for the titanosilicate zeolite membrane according to the present example. In FIG. 3, the horizontal axis represents the wavelength of the diffuse reflection spectrum, and the vertical axis represents the absorbance. In this FIG.
Absorption based on tetracoordinated Ti was observed near 210 nm.
The results shown in FIGS. 2 and 3 confirmed the substitution of Ti atoms in the MFI type skeleton, and confirmed the formation of a titanosilicate type zeolite crystal layer on the surface of the porous support.

  FIG. 4 shows a photograph of the surface of the mixture separation membrane obtained in Example 1 taken with a scanning electron microscope. From FIG. 4, MFI type tita is densely formed on the porous support. It was confirmed that nosilicate type zeolite was deposited.

  Using the zeolite membranes prepared in Examples 1 and 2 and Comparative Example 1, reaction separation of oxidation of 2-propanol (isopropyl alcohol) and ethanol as shown in Formula (1) and Formula (2) was performed.

A schematic diagram of the apparatus used for the reaction separation is shown in FIG. In FIG. 5, reference numeral 1 denotes a zeolite separation membrane prepared in Examples 1 and 2 and Comparative Example 1. The zeolite separation membrane 1 has a hollow cylindrical shape and is immersed in a supply liquid 2 stored in a glass container 9. The supply liquid 2 is a reaction raw material such as 2-propanol or ethanol and a hydrogen peroxide solution, and is stirred by the action of the stirrer 4 and the stirrer 5. The glass container 9 is further immersed in the thermostatic bath 6, and the temperature is maintained constant by the temperature control device 7.
A silicon tube 3 is connected downstream from the upper end of the zeolite separation membrane 1, and the silicon tube 3 is connected via a cold trap 11 to a vacuum line 15 including a vacuum pump 12.
Accordingly, the inside of the zeolite separation membrane 1 is depressurized, and acetone or acetaldehyde, which is a reaction product permeated through the zeolite separation membrane 1 in the supply liquid 2, is collected in the cold trap 11 through the silicon tube 3. Liquefaction.
The feed liquid 2 is blocked by a plug 10 so as not to enter from the bottom of the zeolite separation membrane 1. The degree of vacuum of the vacuum line 15 is measured by a vacuum gauge 14. The N ₂ gas 13 is enclosed at the time of a leak that returns the vacuum line 15 to normal pressure. Since water vapor is mixed when air is inhaled, N ₂ gas 13 is used.

Example 3 (Use Example 1)
A zeolite membrane 1 in which a titanosilicate type zeolite crystal layer was deposited in the form of a film on the porous support prepared in Example 1 was placed in a glass container 9 placed in a thermostatic bath 6 as a feed solution 2 as 2- A propanol (33 wt%) / hydrogen peroxide solution (18 wt%) solution was added to carry out reaction separation. The lower end of the zeolite separation membrane 1 was closed with a stopper 10, and the vapor vaporized permeated through the membrane by being depressurized by a vacuum pump 12 from the opposite side was collected by a cold trap 11. The composition of the permeate was determined by gas chromatography. As a result, after 30 hours, production of 80 wt% acetone as a reaction product was confirmed.

Example 4 (Use Example 2)
A zeolite membrane 1 in which a titanosilicate type zeolite crystal layer was deposited in the form of a film on the porous support prepared in Example 2 was placed in a glass vessel 9 placed in a thermostat 6 as ethanol ( 40 wt%) / hydrogen peroxide solution (18 wt%) was added, and reaction separation was performed at 30 ° C. The lower end of the zeolite separation membrane 1 was closed with a stopper 10, and the vapor vaporized permeated through the membrane by being depressurized by a vacuum pump 12 from the opposite side was collected by a cold trap 11. The composition of the permeate was determined by gas chromatography. As a result, after 48 hours, production of 80 wt% acetaldehyde was confirmed as a reaction product.

Comparative Example 2
Using the MFI type silicalite membrane containing no titanium source prepared in Comparative Example 1, reaction separation of Formula (1) or Formula (2) was performed in the same manner as in Example 1 and Example 2. In either case, the reaction trapping material as well as the reaction raw material were not collected in the cold trap.

In Example 3 or Example 4, acetone or acetaldehyde, which is a reaction product, was put in the glass container 9 as the supply liquid 2 and the same experiment was performed. As a result, acetone and acetaldehyde were not pervaporated.
From these results, the mixture separation membrane of the membrane reactor according to the present embodiment permeates only the reaction raw material without permeating the reaction product, and the titanosilicate type zeolite membrane constituting the separation membrane. With the catalytic function, a reaction product can be generated and then vaporized to be separated from the reaction raw material.
That is, the mixture separation membrane of the membrane reactor according to the present embodiment can separate the reaction raw material and the reaction product by having both a catalytic function and a separation function. In addition, since a membrane obtained by crystallizing titanosilicate zeolite into a membrane is formed on the porous support, the catalytic function directly acts on the reaction raw material, and the reaction efficiency by the catalyst is high. Furthermore, the titanosilicate type zeolite membrane is excellent in film-forming properties, hardly causes defects, and can maintain a high-performance separation function over a long period of time.

In addition, since the silicon tube 3 connected to the upper end of the zeolite separation membrane 1 is decompressed by the vacuum pump 12, the inside of the zeolite separation membrane 1 is also decompressed, and the reaction raw material can be taken into the zeolite separation membrane 1, thereby catalyzing the reaction. It is possible to generate more reaction product vapor that permeates and vaporizes inside the zeolite separation membrane 1.
However, in the membrane reactor according to the present embodiment, as shown in FIG. 5, the reaction product vaporized by connecting the vacuum line 15 to the silicon tube 3 and depressurizing the downstream side of the zeolite separation membrane 1 by the vacuum pump 12. Although the substances acetone and acetaldehyde are sucked, the vacuum line 15 provided with the vacuum pump 12 is not necessarily provided. For example, a line that can be filled with an inert gas such as nitrogen gas is provided, and the reaction is generated by pressurizing the upstream side of the zeolite separation membrane 1 from the surface of the supply liquid 2 stored in the glass container 9. The substance may be guided to the cold trap 11 through the silicon tube 3.
In addition, since the membrane reactor according to the present embodiment includes the cold trap 11, it is possible to collect pervaporated vapor while liquefying it, and it is possible to reduce the volume of the collected reaction product.
Furthermore, since the glass container 9 of the membrane reactor is accommodated in the thermostat 6, the temperature can be adjusted to a temperature suitable for the reaction, and at the same time, the temperature can be controlled to be constant so that the reaction can be performed more efficiently. The product material can be recovered.
In the present embodiment, the glass container 9 is used as a container for storing the supply liquid 2. However, the glass container 9 is particularly limited to glass if it has stable characteristics with respect to the supply liquid 2 and the zeolite separation membrane 1. Instead, for example, a container made of ceramics may be used.

  As described above, from the results of Example 3, Example 4, and Comparative Example 2, in the membrane reactor according to the present embodiment, for example, acetone, which is a reaction product, exhibits high reaction separation in the oxidation reaction of 2-propanol or ethanol. And a remarkable effect of being able to efficiently separate acetaldehyde.

  The membrane reactor according to the present invention can be used for separation of a wide variety of gas mixtures or liquid mixtures. Furthermore, it is possible to separate the reaction product after the catalytic reaction from the reaction raw material before the catalytic reaction by utilizing both the catalytic function and the separation function of the titanosilicate type zeolite membrane, so that only a plurality of types are available. In addition to the separation of the mixture, it can be used in a chemical reaction system or the like that extracts a catalytic reaction product.

All are X-ray diffraction measurement diagrams, (1) is titanosilicate type zeolite crystal powder, (2) is a titanosilicate type zeolite membrane deposited on the porous support prepared in Example 1, (3) is an MFI type silicalite film deposited on the porous support prepared in Comparative Example 1, and (4) is that of the porous support. The titanosilicate type zeolite membrane (1) deposited on the porous support prepared in Example 1 and the MFI type silicalite membrane (2) deposited on the porous support prepared in Comparative Example 1 It is an infrared absorption spectrum measurement figure. FIG. 4 is a measurement result diagram of a diffuse reflection spectrum in an ultraviolet / visible region of a titanosilicate zeolite membrane deposited on a porous support prepared in Example 1. 2 is a scanning electron microscope (SEM) photograph of a titanosilicate zeolite membrane deposited on a porous support prepared in Example 1. FIG. 4 is a schematic view of an apparatus used for reaction separation in Examples 3 and 4 and Comparative Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Zeolite separation membrane 2 ... Supply liquid 3 ... Silicon tube 4 ... Stirrer 5 ... Stirrer 6 ... Constant temperature bath 7 ... Temperature control device 8 ... Cooling tube 9 ... Glass container 10 ... Plug 11 ... Cold trap 12 ... Vacuum pump 13 ... N ₂ gas 14 ... Vacuum gauge 15 ... Vacuum line

Claims (3)

  A mixture separation membrane having a titanosilicate type zeolite crystal layer deposited on a porous support, a reaction vessel provided upstream of the mixture separation membrane and containing a reaction raw material, and a downstream side of the mixture separation membrane And a pipe for connecting the one end to the reaction product.   The membrane reactor according to claim 1, wherein the pipe includes a cooling unit that cools a reaction product. The membrane reactor according to claim 1 or 2, wherein the reaction vessel is housed in a thermostat capable of adjusting temperature.