JP2001129373A - Separation membrane and separation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separation membrane for efficiently separating ether and alcohol especially MTBE and methanol from a mixed solution containing the ether and the alcohol, and a separation method using the separation membrane. SOLUTION: A membrane comprising a compound containing agar and/or agarose or a membrane comprising a mixture prepared by adding at least one kind of a compound selected from polyoxyethylene, hydroxyalkylcellulose and sericin to the compound containing the agar and/or the agarose is provided. When ether and alcohol are separated from a mixed solution containing the ether and the alcohol by using the separation membrane, separation is performed in such a condition that an upstream side of the membrane is set in a liquid state, and a downstream side thereof is set in a vapor state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a separation membrane and a separation method comprising a compound containing agar and / or agarose. Specifically, a mixed solution containing an ether and an alcohol obtained by reacting an olefin with an alcohol is supplied to a membrane composed of a compound containing agar and / or agarose to selectively permeate the alcohol.
That is, the present invention relates to a separation membrane for separating ether and alcohol by removing alcohol, and a separation method using the separation membrane.

[0002]

2. Description of the Related Art Methyl-t-butyl ether (hereinafter, referred to as "MTBE") which improves the anti-knock property of gasoline is one of the commercially valuable ether compounds obtained from olefins and alcohols as raw materials. The production of MTBE is generally carried out in the liquid phase using one or two fixed-bed catalytic reactors, starting from isobutene and methanol. After the reaction, MTBE is produced by separating and removing unreacted methanol. However, MTBE is azeotropic with methanol (azeotropic composition:
MTBE / methanol = 85.7% by weight / 14.3% by weight), a typical separation method, that is, MTBE and unreacted methanol are separated by distillation to obtain high purity M
The method of obtaining TBE requires huge and complicated facilities and processes, often requires a large amount of energy,
This is not an advantageous method.

As a method for obtaining high-purity MTBE from a mixed solution of MTBE and methanol by a method other than the distillation method, an adsorption separation method and a membrane separation method are disclosed. As the adsorption separation method, U.S. Pat. No. 4,605,787 discloses a method of adsorbing and removing methanol using zeolite. However, there are problems such as an expensive adsorbent, a need for a desorption process, and difficulty in continuity.
As a membrane separation method, Japanese Patent Publication No. 6-67866 discloses a cellulose acetate membrane and a polyvinyl alcohol membrane as preferred membranes, and a method by pervaporation using these membranes is called AICHE Symposium.
Series, No. 272, Vol. 85, p. 8
2-88 (1989) discloses a method based on pervaporation using a cellulose acetate membrane.
No. 916 discloses a method by pervaporation using a poly (vinylpyridine) film crosslinked with a polyhalide. Generally, the membrane separation method consumes less heat energy than the distillation method and is easy to be continuous, so that it is expected as an effective method for liquid separation in the future. However, the membrane of the above disclosed technology has not so high permeation selectivity to methanol (selectivity is 14 to 400 in Japanese Patent Publication No. 6-67866, A
In ICHE Symposium Series,
20, 20 to 550 in JP-A-6-86916. ), The performance was insufficient to obtain high-purity MTBE.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a separation membrane for efficiently separating ether and alcohol, particularly MTBE and methanol from a mixed solution containing ether and alcohol, and a separation method using the separation membrane. To provide.

[0005]

The present inventors have a function of selectively permeating and removing methanol from a mixed solution containing ether and alcohol, particularly a mixed solution containing MTBE and methanol, that is, a function of removing methanol. As a result of intensive studies on a separation membrane having a function of separating ether and alcohol and a separation method thereof, it was found that a membrane composed of a compound containing agar and / or agarose contained MTB.
It is a membrane that has a function to selectively permeate methanol from a mixed solution containing E and methanol, and is a membrane that efficiently separates ether and alcohol. Pervaporation using this membrane is an effective separation method. The inventors have found that the present invention has been completed.

The first invention of the present invention is constituted by a compound containing agar and / or agarose, and selectively permeating alcohol from a mixed solution containing ether and alcohol, whereby ether and alcohol, especially, MT
This is a separation membrane for separating BE and methanol.

The second invention of the present invention comprises a mixture of a compound containing agar and / or agarose and at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin. And a separation membrane for separating ether and alcohol from a mixed solution containing ether and alcohol. The third invention of the present invention uses the separation membrane according to any one of the first invention and the second invention, and selectively permeates alcohol from a mixed solution containing ether and alcohol, thereby forming ether and alcohol. This is a separation method for separating alcohol, particularly MTBE and methanol.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The film composed of the agar and / or agarose-containing compound used in the present invention is a sheet-like agar and / or agarose-containing compound or agar and / or agarose-containing compound.
Alternatively, a specific load is applied to a gel obtained from a mixture obtained by adding at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin to a compound containing agarose, and drying is performed while applying a specific load. It is a film with good surface smoothness.

The sheet-like gel comprising the compound containing agar and / or agarose is prepared from a solution of agar and / or agarose in a solvent such as water. A mixture of agar and / or agarose-containing compound and at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin is a mixture of only agar and / or agarose-containing compound. As compared with the case, the stability of the formed gel was better and the preparation of the sheet gel was easier. When at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose, and sericin is added to the agar- and / or agarose-containing compound, the gel is formed using agar and / or agarose. Prepared in a similar manner as for the compound alone.

Various types of agar and agarose are commercially available, and any type of agar or agarose can be used in the present invention without any restrictions. When both agar and agarose are used for preparing the gel, a mixture of both components in an arbitrary ratio can be used. When at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose, and sericin is added to the compound containing agar and / or agarose, the mixing ratio is not limited as long as a gel is formed. Usually, at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose, and sericin is used in an amount of 0.1 to 1, based on 100 parts by weight of the compound containing agar and / or agarose. 0
00 parts by weight, preferably 0.1 to 400 parts by weight. Further, polyoxyethylene, hydroxyalkylcellulose, and sericin may be used alone or may be mixed at an arbitrary ratio.

The polyoxyethylene used in the present invention is not particularly limited as long as it is a commercially available polyoxyethylene, but is preferably a solid at room temperature and has a number average molecular weight of 1,
000-50,000 polyoxyethylenes are preferred. When polyoxyethylene alone is added to the compound containing agar and / or agarose, the more preferable blending ratio of polyoxyethylene is 0.1 to 75% by weight.

Hydroxyalkyl cellulose is usually
It is a water-soluble cellulose derivative produced by reacting an alkyl cellulose with an alkylene oxide such as ethylene oxide or propylene oxide. Industrially, hydroxyethyl cellulose and hydroxypropyl cellulose having various degrees of polymerization are manufactured and sold. In the present invention, commercially available hydroxyalkylcellulose can be used without particular limitation, but if anything, hydroxyethylcellulose is preferably used. Hydroxyalkyl cellulose alone with agar and / or
Or when it is added to a compound containing agarose, the more preferable mixing ratio of hydroxyalkyl cellulose is 0.1.
1 to 50% by weight.

[0013] Sericin is a water-soluble hard protein excreted in the course of refining silk. Amino acid content is similar to fibroin, but less glycine, alanine and tyrosine and more serine, glutamic acid and aspartic acid than fibroin. In the present invention,
Commercial products having these properties are used without particular restrictions. When sericin is added alone to the compound containing agar and / or agarose, the more preferable compounding ratio of sericin is 0.1 to 60% by weight.

In preparing the solution, water is preferably used as a solvent. The type of water is not particularly limited, but tap water, ion-exchanged water, distilled water, and the like are preferably used. Also,
If necessary, another suitable solvent can be mixed with water. Specific examples of the solvent to be mixed with water include aliphatic lower alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone and ethyl methyl ketone, esters such as methyl acetate and ethyl acetate, and aqueous solvents such as acetonitrile and the like. Organic solvents. These can be used alone or as a mixture of two or more kinds in water. The ratio of the solvent other than water to the total solvent is more than 0% by weight and 20% by weight.
Or less, preferably more than 0% by weight and 10% by weight or less. If the amount of the solvent other than water exceeds 20% by weight, agar and / or agarose may precipitate when the solution is cooled, and it is difficult to obtain a gel in a uniform state.

A compound containing agar and / or agarose or a mixture of a compound containing agar and / or agarose with at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin. The solution is obtained by heating a mixture of these compounds or a mixture thereof and water to 50 ° C. or higher, preferably 60 ° C. or higher. When the temperature is lower than 50 ° C., the dissolution requires a remarkably long time, which is not practical.
Compounds containing agar and / or agarose in solution and polyoxyethylene, hydroxyalkyl cellulose,
The concentration of the component such as sericin is not particularly limited as long as the concentration is such that the solution becomes a gel when the solution is cooled to 40 ° C. or lower, but is preferably 0.01 to 10% by weight, more preferably 0.1 to 5% by weight. % By weight. When the concentration is less than 0.01% by weight, the strength of the obtained gel may be too weak. On the other hand, if the concentration exceeds 10% by weight, insolubles may be present during the preparation of the solution, or the viscosity of the solution may be high, so that the operability of forming the sheet gel may deteriorate, which is not preferable.

In order to obtain a sheet-like gel, generally, the solution obtained above may be cooled by transferring it to a container having a flat bottom such as a petri dish or vat. The cooling temperature is preferably from 0 to 40C, more preferably from 0 to 30C.
If the cooling temperature exceeds 40 ° C., it takes a long time to form a gel, which is not practical. If the temperature is lower than 0 ° C., water in the solution may freeze, and a gel in a uniform state may not be obtained. The thickness of the sheet-like gel is arbitrarily determined depending on the thickness of the film to be obtained, and is adjusted by the bottom area of the container used for forming the sheet and the amount of the gel to be put in the container. Generally, the thickness of the sheet gel is preferably 0.1 to 10 mm because of easy operation.

A film containing agar and / or agarose or a mixture of a compound containing agar and / or agarose and at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin is added. An example of a method for producing a film is described below. From the sheet-like gel obtained above, a sheet-like gel having substantially the same size as the film to be manufactured (length × width) is cut out. A predetermined amount of load is directly applied to the cut sheet gel, or a porous material having the same area or more as the sheet gel is laminated on one or both sides of the cut sheet gel, and then a predetermined amount of load is applied. Add or, after laminating a porous material on one or both sides of the sheet gel, further laminating a water absorbing material on one or both sides,
A predetermined amount of load is applied thereto, and the temperature is maintained at 0 to 40 ° C., and agar gel containing agar and / or agarose or a compound containing agar and / or agarose is added to polyoxyethylene, hydroxyalkyl cellulose,
After removing moisture from a sheet gel from a mixture containing at least one compound selected from the group consisting of sericin and drying, the porous material and / or water-absorbing material is removed to contain agar and / or agarose. A membrane is produced from a mixture of a membrane or a compound containing agar and / or agarose and at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin. The porous material and the water-absorbing material may be used on either one side or both sides of the sheet-like gel, but if anything, it is better to use them on both sides because moisture can be removed efficiently.

At least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin is added to the obtained film containing agar and / or agarose or a compound containing agar and / or agarose. Since the film from the mixed mixture is manufactured under the above-mentioned specific conditions, it can be dehydrated and dried in a uniform state, the variation in the film thickness is small, and there are large voids on the film surface and inside that affect the properties. No, it is a film with good surface smoothness.

The porous material used above is preferably a porous material having a pore communicating from the front surface to the back surface of the membrane. There are no particular restrictions on the pore diameter or porosity, but the pore diameter is preferably smaller than 0.5 mm, the porosity is 5% or more,
Preferably, it is 30% or more. These porous materials are preferably those having low adhesiveness to the sheet gel,
Specific examples of these include hydrophobic polymers such as polyethylene, polypropylene, polytetrafluoroethylene, polychlorotrifluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, and polyvinylidene fluoride. These do not need to be specially prepared, and commercially available polymer porous films can be used as they are. In addition, a polymer film having a porosity of 0%, which is not a porous material, may be used as long as the material has a property of transmitting water or water vapor.

The water-absorbing material laminated on one or both sides of the sheet-like gel or a laminate of the sheet-like gel and the porous material absorbs moisture and water vapor transmitted through the porous material and promotes drying of the gel. Used for Therefore,
A porous material having water absorption is preferably used. Specific examples of these water-absorbing porous materials include papers such as filter paper, and hydrophilic polymers such as cellulose, cellulose acetate, and nylon. These hydrophilic polymers are often used in the form of a woven fabric, a nonwoven fabric, or the like. These water-absorbing porous materials such as filter paper can further promote the drying of the gel by being appropriately replaced depending on the moisture absorbing state.

The load applied to the above-mentioned sheet gel or a laminate comprising the sheet gel and the porous material and / or the water-absorbing material should be uniformly applied to almost the entire surface of the sheet from a direction as perpendicular to the sheet surface as possible. preferable. The load may be applied from either one side or both sides of the sheet, but it is preferable to apply the load to the sheet surface as uniformly as possible. The applied load varies depending on the moisture content of the gel, the type of agar and / or agarose, etc., but is generally 0.01 to 2 kgf /
cm ² . If the applied load is out of the above range,
The thickness of the obtained film may vary, the surface of the film may be depressed, and voids may be generated on the surface or inside of the film.

The temperature at which the sheet gel is dried and dehydrated while applying a load is 0 to 40 ° C. If the temperature is lower than 0 ° C., the moisture in the gel may freeze, making it difficult to obtain a good film. On the other hand, when the temperature exceeds 40 ° C., the gel dissolves and it becomes difficult to obtain a film having good surface smoothness, or voids are generated on the surface or inside of the film, so that a good film may be obtained. It becomes difficult.

The time for drying the gel while applying a load is appropriately selected depending on the load and the temperature, but is generally preferably several hours to several weeks. Further, the thickness of the film of the present invention,
Usually, it is 1 to 100 μm.

A heat stabilizer, an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, an antiseptic, a fungicide, a bactericide, and the like may be added to the film as long as the effects of the present invention are not impaired. it can.

The kind of the mixed solution of ether and alcohol to be separated in the present invention is not particularly limited, but a mixed solution of ether and alcohol obtained by reacting an olefin with alcohol is preferable. Particularly, a mixed solution of MTBE and methanol obtained by reacting isobutene and methanol is preferable. It is possible to separate a mixed solution containing MTBE and methanol mixed at an arbitrary ratio. Further, the mixed solution may contain a solvent other than ether or alcohol.

In the separation method of the present invention, since the separation target is a mixed solution containing ether and alcohol, and the membrane to be used has substantially no pores, the upstream side (supply side) of the membrane is in a liquid state. The pervaporation method of operating the downstream side (permeate side) in a vapor state is preferably employed. Specifically, for example, a mixed solution containing MTBE and methanol is supplied to one side of the membrane, an inert gas is flowed through the membrane to the permeation side, or a vacuum pump is connected to reduce the pressure. The separation operation can be performed efficiently by recovering the components that have passed through the membrane as vapor.

The operating pressure is set between the atmospheric pressure and 5 kgf /
cm ² , the permeate side is preferably maintained at a reduced pressure of 200 mmHg or less, the supply side at atmospheric pressure, and the permeate side at 100 mmHg.
It is particularly preferable to maintain a reduced pressure of not more than mmHg. Even if the pressure on the supply side is reduced or the pressure is higher than 5 kgf / cm ² , the flux and the separation coefficient are not affected at all, and the facility cost is increased but there is no advantage. When the pressure on the permeation side is 200 mmHg or more, the recovery rate of the permeated component may be deteriorated. The temperature in the separation operation is not particularly limited as long as the supply liquid can be handled in a liquid state,
5 to 60 ° C is preferred, and 10 to 50 ° C is particularly preferred.
If the temperature is lower than 5 ° C., the flux may decrease, and if it exceeds 60 ° C., the separation coefficient may decrease,
Neither is preferred.

Usually, in order to efficiently perform membrane separation, the membrane is often used in the form of a module. There is no limitation on using a known membrane module configuration for the membrane of the present invention. Examples of the membrane module form include a plate & frame type module and a spiral type module. In addition, as the membrane separation device used for separating the mixed solution containing ether and alcohol using the membrane of the present invention, a known pervaporation device can be used without any limitation.

The separation function of the membrane is evaluated by the following method.
While supplying a mixed solution of ether and alcohol at a predetermined concentration to the membrane, the vapor permeating the membrane is collected by a trap cooled by liquid nitrogen or the like. Predetermined time (t;
The permeation amount is measured in units of h), and the separation function is evaluated with a steady state after the permeation amount becomes constant. From the permeation amount (P; unit is g) in the steady state, the flux (hereinafter, referred to as “J”) can be obtained by equation (1). Further, the concentration of ether and alcohol in the permeated liquid is quantified using a gas chromatograph, and a separation coefficient (hereinafter referred to as “α”) can be obtained from this concentration and the concentration of the feed solution by the equation (2). .

J = P / At (1) Explanations of symbols used in the equation (1) are as follows. J: flux, unit is gm ⁻² h ⁻¹ P: permeation amount, unit is g A: membrane area, unit is m ² t: predetermined time, unit is h

Α = (Y- _alcohol / Y- _ether ) / (X- _alcohol / X- _ether ) (2) Explanations of symbols used in the formula (2) are as follows. α: separation coefficient Y _alcohol : concentration of alcohol in the permeate, unit is weight% Y _ether : concentration of ether in the permeate, unit is weight% X _alcohol : concentration of alcohol in the feed solution, unit is weight% X _Ether : concentration of ether in feed solution, unit is wt%

Hereinafter, the present invention will be described in detail with reference to examples.

[0031] powder agarose Erlenmeyer flask of Example 1 made film 200ml (Japan Bio Laboratories, Inc., agarose Standard Lo
w-mr, Gel Strength ≧ 1000 g / c
0.4 g of m ² (1.0% gel) and 8 mg of sodium azide as a fungicide were added, and ion-exchanged water was added to make a total amount of 40 g. This was heated to 60 ° C. to prepare a uniform aqueous solution. The whole amount of the aqueous solution was put in a 14 cm × 15 cm square vat having a smooth bottom, and kept at room temperature for 24 hours while maintaining a horizontal state, thereby preparing a sheet-like agarose gel. On the other hand, another bat was prepared on a horizontal table, and this bat was 14 cm x 1 from the bottom.
5cm square filter paper (Advantech, Toyo Roshi Kaisha, N
o. 2) 14 cm × 15 cm square polytetrafluoroethylene porous film (Advantech, Toyo Roshi Kaisha, PTFE, average pore size 0.1 μm), sheet-shaped agarose gel previously prepared, polytetrafluoroethylene porous film, filter paper , And a load of approximately 21.9 kg having almost the same dimensions was placed thereon (load: about 0.104 kgf / cm ² ). The filter paper was dried at room temperature for 15 days while replacing it with a new one every 1-2 days. The obtained film was a colorless and transparent film-like film having a thickness of 15 to 17 μm. The film thickness was measured using a thickness gauge (DIGITAL MICROMETER M-30, Sony Magnescale Inc.
Was used to measure five arbitrary points on the film, and the maximum and minimum film thicknesses were described. Membrane separation About 5 cm in diameter from the agarose membrane obtained by the above method
Was cut out and mounted on a stainless steel perforated plate of a stainless steel pervaporation apparatus. The effective membrane area used for membrane permeation was 17.3 cm ² . On top of this film, a mixed solution containing MTBE and methanol (composition: MTB
E / methanol = 90.421% by weight / 9.579% by weight). The pressure on the supply side is atmospheric pressure,
A vacuum pump and a pressure regulator are connected to the
It was adjusted to mmHg. The temperature was adjusted to 30 ° C. by circulating constant temperature water throughout the apparatus, and pervaporation was performed.
The weight of the solution permeating through the membrane and collected in the trap at predetermined time intervals is measured, and J is calculated from the weight when the weight per unit time becomes constant, and α is calculated from the permeated liquid composition and the charged liquid composition at that time. I asked. Table 1 shows the obtained J and α.
The methanol concentration in the permeate was 99.99% by weight or more, and the membrane substantially permeated methanol from the mixed solution of MTBE and methanol, and separated MTBE and methanol.

Example 2 A film was formed in the same manner as in Example 1 except that 0.4 g of agar powder (manufactured by Wako Pure Chemical Industries) was used instead of the agarose powder of Example 1. The obtained film was a colorless and transparent film-like film having a thickness of 18 to 19 μm. Using membrane separation resulting agar film, composition, MTBE / methanol = 48.252 wt% / 51.746 except that a mixed solution containing wt% was feed is likewise pervaporation Example 1 Was done. Table 1 shows the obtained J and α. The concentration of methanol in the permeate was 99.99% by weight or more, and the membrane substantially permeated methanol from the mixed solution of MTBE and methanol to separate MTBE and methanol.

Example 3 Film formation In place of the powdered agarose of Example 1, powdered agarose (Agarose Standard Low-mr, Gel Strength ≧ 10, manufactured by Nippon Bio Laboratories)
The procedure was performed in the same manner as in Example 1, except that 0.2 g of (00 g / cm ² (1.0% gel)) and 0.2 g of powdery agar (manufactured by Wako Pure Chemical Industries) were used. The obtained film was a colorless and transparent film-like film having a thickness of 15 to 18 μm. Using a blend film containing a membrane separation resulting agar and agarose,
The composition is MTBE / methanol = 7.903% by weight / 9
Pervaporation was performed in the same manner as in Example 1 except that a mixed solution containing 2.097% by weight was used as a supply liquid.
Table 1 shows the obtained J and α. The methanol concentration in the permeate is 99.9% by weight or more, and the membrane substantially permeates methanol from a mixed solution of MTBE and methanol,
MTBE and methanol were separated.

Example 4 Using the agarose film formed in Example 1, the composition was MTBE / methanol = 69.66% by weight / 30.
Pervaporation was carried out in the same manner as in Example 1, except that the mixed solution containing 34% by weight was used as the supply liquid. Table 1 shows the obtained J and α. The methanol concentration in the permeate is 9
9.99% by weight or more, and the membrane substantially permeates methanol from a mixed solution of MTBE and methanol,
E and methanol were separated.

Example 5 Using the agarose film formed in Example 1, the composition was MTBE / methanol = 27.984% by weight / 7.
Pervaporation was carried out in the same manner as in Example 1 except that a mixed solution containing 2.016% by weight was used as a supply liquid.
Table 1 shows the obtained J and α. The methanol concentration in the permeate is 99.9% by weight or more, and the membrane substantially permeates methanol from a mixed solution of MTBE and methanol,
MTBE and methanol were separated.

[0036]

[Table 1]

[0037] powder agarose Erlenmeyer flask of Example 6 made film 200ml (Japan Bio Laboratories, Inc., agarose Standard Lo
w-mr, Gel Strength ≧ 1000 g / c
0.4 g of m ² (1.0% gel)), 0.4 g of polyoxyethylene (manufactured by Nakarai TeX Co., Ltd., POE = 20,000, number average molecular weight of 15,000 to 25,000) and 8 mg of sodium azide as a fungicide were added. Was carried out in the same manner as in Example 1 except that ion-exchanged water was added to make the total amount 40 g. Thus, a membrane containing agarose and polyoxyethylene was produced. The obtained film was a colorless and transparent film having good surface smoothness, and had a thickness of 23 to 29 μm. Membrane separation Same as Example 1 except that a membrane having a diameter of about 5 cm was cut out from the membrane containing agarose and polyoxyethylene obtained by the above method and mounted on a stainless steel perforated plate of a stainless steel pervaporation apparatus. Pervaporation was performed by the method. Table 2 shows the obtained J and α. The methanol concentration in the permeate was 99.99% or more, and the membrane substantially permeated only methanol from the mixed solution of MTBE and methanol, and separated MTBE and methanol.

Example 7 Using the film formed in Example 6, the composition was changed to MTB.
Pervaporation was carried out in the same manner as in Example 1, except that a mixed solution containing E / methanol = 69.115% by weight / 30.885% by weight was used as a supply liquid. Table 2 shows the obtained J and α. The methanol concentration in the permeate was 99.9.
9% or more, and this membrane substantially permeated methanol from the mixed solution of MTBE and methanol, and separated MTBE and methanol.

Example 8 Using the film formed in Example 6, the composition was changed to MTB.
Pervaporation was carried out in the same manner as in Example 1, except that a mixed solution containing E / methanol = 49.528% by weight / 50.472% by weight was used as a supply liquid. Table 2 shows the obtained J and α. The methanol concentration in the permeate was 99.9.
9% or more, and this membrane substantially permeated methanol from the mixed solution of MTBE and methanol, and separated MTBE and methanol.

[0040]

[Table 2]

[0041] powder agarose Erlenmeyer flask of Example 9 made film 200ml (Japan Bio Laboratories, Inc., agarose Standard Lo
w-mr, Gel Strength ≧ 1000 g / c
0.4 g of m ² (1.0% gel)), 0.1 g of hydroxyethylcellulose (HEC Daicel SP600, manufactured by Daicel Chemical Industries, Ltd.) and 8 mg of sodium azide as a fungicide, and ion-exchanged water was added thereto. Was changed to 40 g in the same manner as in Example 1. The obtained film was a colorless and transparent film having good surface smoothness, and the film thickness was 18 to 20 μm. Membrane separation A membrane having a diameter of about 5 cm was cut out from the membrane containing agarose and hydroxyethylcellulose obtained by the above method,
Pervaporation was carried out in the same manner as in Example 1, except that the pervaporation was carried out on a stainless steel perforated plate of a stainless steel pervaporation apparatus. Table 3 shows the obtained J and α. The concentration of methanol in the permeate was 99.99% by weight or more, and the membrane substantially permeated methanol from the mixed solution of MTBE and methanol to separate MTBE and methanol.

Example 10 Using the film formed in Example 9, the composition was changed to MTB.
Pervaporation was carried out in the same manner as in Example 1, except that a mixed solution containing E / methanol = 28.078% by weight / 71.922% by weight was used as a supply liquid. Table 3 shows the obtained J and α. The methanol concentration in the permeate was 99.
9 wt% or more, the membrane substantially permeated methanol from the mixed solution of MTBE and methanol, and separated MTBE and methanol.

Example 11 Using the film formed in Example 9, the composition was changed to MTB.
Pervaporation was carried out in the same manner as in Example 1, except that a mixed solution containing E / methanol = 9.390% by weight / 90.610% by weight was used as a supply liquid. J and α obtained
Are shown in Table 3. The concentration of methanol in the permeate was 99.9% by weight or more, and the membrane substantially permeated methanol from the mixed solution of MTBE and methanol to separate MTBE and methanol.

[0044]

[Table 3]

Example 12 Film formation agarose powder (Agarose Standard, G, manufactured by Nippon Bio Laboratories) was placed in a 200 ml Erlenmeyer flask.
el Strength ≧ 1000 g / cm ² (1.0
% Gel)), 0.3 g of sericin (manufactured by Seiren; number average molecular weight of about 20,000) and 8 mg of sodium azide as a fungicide, and ion-exchanged water was added thereto to make the total amount 40 g. It carried out similarly to Example 1. The obtained film was a colorless and transparent film having good surface smoothness, and had a thickness of 23 to 25 μm. Membrane separation A membrane having a diameter of about 5 cm was cut out from the membrane containing agarose and sericin obtained by the above method and mounted on a stainless steel perforated plate of a stainless steel pervaporation apparatus in the same manner as in Example 1 except that the pervapor was used. Rations. Table 4 shows the obtained J and α. The methanol concentration in the permeate is 99.99% by weight or more.
Methanol was substantially permeated from the mixed solution of TBE and methanol, and MTBE and methanol were separated.

Example 13 Using the film formed in Example 12, the composition was changed to MT.
BE / methanol = 69.228% by weight / 30.772
Example 1 except that the mixed solution containing% by weight was used as the feed solution.
Pervaporation was performed in the same manner as described above. Table 4 shows the obtained J and α. The methanol concentration in the permeate was 99.
At least 99% by weight, the membrane substantially permeated methanol from the mixed solution of MTBE and methanol, and separated MTBE and methanol.

Example 14 Using the film formed in Example 12, the composition was changed to MT.
BE / methanol = 48.411% by weight / 51.589
Example 1 except that the mixed solution containing% by weight was used as the feed solution.
Pervaporation was performed in the same manner as described above. Table 4 shows the obtained J and α. The methanol concentration in the permeate was 99.
It was 99% by weight or more, and this membrane substantially permeated methanol from a mixed solution of MTBE and methanol, and separated MTBE and methanol.

[0048]

[Table 4]

[0049]

According to the present invention, at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin is added to a film made of a compound containing agar and / or agarose or a compound containing agar and / or agarose. The membrane made of the mixture has a high ability to selectively permeate alcohol from a mixed solution of ether and alcohol,
It is a separation membrane for separating ether and alcohol, particularly for separating MTBE and methanol, which is useful as an anti-knock agent for gasoline. By removing methanol by pervaporation using this film, high-purity MTBE can be obtained.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D006 GA25 HA42 HA61 KE07R KE08R KE16R MA03 MA06 MA22 MA24 MA31 MC09X MC10X MC19X MC22 MC22X MC23 MC28 MC29 MC30 MC83 MC88 NA47 PA03 PB12 PB32 PB70

Claims (5)

[Claims] 1. A separation membrane composed of a compound containing agar and / or agarose and separating ether and alcohol from a mixed solution containing ether and alcohol. 2. A mixture comprising a compound containing agar and / or agarose and at least one compound selected from the group consisting of polyoxyethylene, hydroxyalkylcellulose and sericin, and containing ether and alcohol. A separation membrane that separates ether and alcohol from the mixed solution. 3. A separation method for separating ether and alcohol by selectively permeating alcohol from a mixed solution containing ether and alcohol using the separation membrane according to claim 1 or 2. 4. The separation method according to claim 3, wherein the ether of the mixed solution containing the ether and the alcohol is methyl-t-butyl ether, and the alcohol is methanol. 5. An upstream side of the separation membrane according to claim 1 or 2, wherein the separation membrane according to claim 1 or 2 is used to separate ether and alcohol from a mixed solution containing ether and alcohol. 5. The method according to claim 3, wherein the downstream side is in a vapor state.