JP2993217B2 - Method for producing hollow fiber-shaped porous separation membrane element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a hollow fiber-shaped porous separation membrane element, and more particularly, it is used as a gas separation membrane, a dialysis membrane, a reverse osmosis membrane, an ultrafiltration membrane, a microfiltration membrane, or the like. The present invention relates to a method for producing a hollow fiber-like porous separation membrane element having excellent heat resistance, chemical resistance, and the like using a hollow fiber-like porous separation membrane.

[0002]

2. Description of the Related Art A hollow fiber type porous separation membrane is a separation membrane that uses the walls of hollow fibers as a selective permeable membrane, and is a gas separation membrane, a dialysis membrane, a reverse osmosis membrane, an ultrafiltration membrane, a microfiltration membrane. It is used for such purposes. This hollow fiber-shaped porous separation membrane has been put into practical use as a hollow fiber type module in order to increase the membrane area per unit volume.

The hollow fiber module includes an element in which a bundle of hollow fiber porous separation membranes (hollow fibers) is housed in a pressure-resistant outer cylinder such as a cylinder, and has a high packing density of the membrane.
It can be used to reduce the size of filtration equipment that separates liquid useful substances such as water, juice, alcohol, and solvents from dust, germs, etc., and because of its excellent pressure resistance, it is often used in the semiconductor, food, and other fields. Used. In particular, a hollow fiber-shaped porous separation membrane made of a hydrophobic resin such as a fluororesin has been awarded due to its excellent chemical resistance.

[0004] The hollow fiber type module uses an element in which a bundle of a large number of hollow fiber-shaped porous separation membranes is housed in an outer cylinder such as a cylinder, and one end of the hollow fiber-shaped porous separation membrane is heat-sealed and sealed. There are a closed internal pressure type separation membrane element and an internal pressure circulation type separation membrane element having openings at both ends. In these elements, a bundle of a large number of hollow fiber-like porous separation membranes is housed in an outer cylinder, and at one or both ends thereof, a gap between the hollow fiber-like porous separation membranes and a gap between the hollow fiber-like porous separation membrane and the outer cylinder are provided. Is sealed with a sealant or the like.

Conventionally, as a method of sealing the gap between the outer cylinder and the hollow fiber bundle or the gap between the hollow fiber bundles, a low-viscosity resin such as an epoxy resin, a urethane resin, or a silicone resin is used as a sealant at the terminal. A method is known in which the material is injected, allowed to stand still or centrifugal force to sufficiently fill the gap, and then heated and cured (JP-B-44-5526, JP-B-56-40602).
issue).

However, these resins used as sealants are not sufficient in terms of heat resistance and chemical resistance, and a solution or an organic solvent containing an acid or an alkali is used as a solvent or a cleaning solution, or steam sterilization. There was a limit to applying to the fields that do. That is, although the epoxy resin is relatively excellent in heat resistance, it is fragile to strong acids, strong alkalis and some solvents, has skin sensitization, and its application in the field of medicine and food is limited. Urethane resins have insufficient heat resistance and do not have resistance to strong acids, strong alkalis and some solvents. Silicone resins have poor solvent resistance.

On the other hand, when a hot-melt resin is used as a sealant for a hollow fiber-shaped porous separation membrane element, (1)
A method of injection molding or extrusion molding in which an outer cylinder containing a hollow fiber bundle is placed in a mold, and the resin is heated and melted and poured.
(2) Placing the outer cylinder containing the hollow fiber bundle in the mold,
Put the granular or pellet resin into the mold and heat and melt,
There are a method of defoaming bubbles contained in the resin, a method of (3) molding a resin having a honeycomb-shaped through hole in advance, mounting a hollow fiber in the hole, and then thermally melting the resin.

However, in the method (1), when the viscosity of the hot-melt resin is high, it is difficult to make the resin penetrate into narrow gaps such as the gap between the outer cylinder and the hollow fiber bundle or between the hollow fiber bundles. is there. In the method (2), it is difficult to remove air bubbles that have entered once from the high-viscosity resin, resulting in incomplete sealing. In the method (3), it is difficult to form a large number of through holes at a high density, and it is inevitable to mix air bubbles, and it is difficult to completely seal the gap. Therefore, according to these methods, the sealing portion cannot be finely molded using the heat-fusible resin, and the filling rate of the hollow fiber cannot be increased.

[0009] The greatest advantage of the hollow fiber-shaped porous separation membrane element is that the membrane area per unit volume can be increased. For that purpose, it is essential to highly fill the outer cylinder with the hollow fiber, It is generally said that the filling rate of the hollow fiber (the ratio of the total volume including the lumen of the hollow fiber to the volume of the element) needs to be 50% or more. However, it is extremely difficult to prepare a hollow fiber-shaped porous separation membrane element having a high filling rate by using a heat-meltable resin as a sealing agent. Particularly, since a heat-meltable resin having excellent heat resistance and chemical resistance generally has a high melting point and a high viscosity, it was actually impossible to use it as a sealant by a conventionally known molding method.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a hollow fiber-like porous separation membrane element having a high filling factor and significantly improved heat resistance and chemical resistance. Further, an object of the present invention is to manufacture a hollow fiber-shaped porous separation membrane element including a step of forming a terminal sealing portion of a hollow fiber-shaped porous separation membrane element using a heat-meltable resin such as a heat-meltable fluororesin. It is to provide a method.

Although the heat-meltable fluororesin is excellent in heat resistance and chemical resistance, it generally has a high melting point and a high viscosity. It is extremely difficult to form an end seal of a quality separation membrane element, and a satisfactory product cannot be obtained. For example, the specific melting viscosity of a molding resin of FEP (tetrafluoroethylene / hexafluoropropylene copolymer) is generally as high as 10 ⁴ to 10 ⁶ poise, and there is almost no fluidity without melting even if it is melted.
Therefore, in order to use a hot-melt fluororesin as a sealant for sealing the end of a hollow fiber-shaped porous separation membrane element, high pressure is required to allow the resin to penetrate into fine gaps, and conventional molding techniques require It was thought to be virtually impossible.

As described above, the highly viscous heat-meltable resin penetrates into the finely shaped portions such as the gaps between the hollow fiber-shaped porous separation membranes and the gaps between the hollow fiber-shaped porous separation membranes and the outer cylinder, so that the end sealing portion is formed. Was thought to be extremely difficult or impossible. On the other hand, the present inventor, contrary to the conventional idea, fills the gaps between the hollow fiber-shaped porous separation membranes with the heat-meltable resin in a state where the gaps are sparse, and then heats the heat-meltable resin. It has been found that when melted and compressed, a terminal sealing portion is formed with a hot-melt resin, and a hollow fiber-shaped porous separation membrane element having a high filling rate can be obtained. The present invention has been completed based on these findings.

[0013]

Thus, according to the present invention, a preform having a shape in which one end of a number of hollow fiber-like porous separation membranes is inserted into a hot-melt resin is prepared, and then the preform is formed. By applying pressure from the surroundings while heating and melting the hot-melt resin, the gap between the hollow fiber-shaped porous separation membranes is reduced, and the end sealing portion made of the hot-melt resin having a desired shape is formed. A method for producing a hollow fiber-shaped porous separation membrane element is provided.

Hereinafter, the present invention will be described in detail. The root of the technical idea of the present invention is to integrate the hollow fiber-shaped porous separation membrane and the sealing agent at a low filling rate that is easy to produce, and then to narrow down the density to increase the density.

The manufacturing method of the present invention will be described with reference to the drawings. As shown in FIG. 1, first, a terminal portion in which a hollow fiber-shaped porous separation membrane 1 having a low filling rate and a sealant 2 made of a hot-melt resin are integrated is formed. In this case, a support rod 6 made of a heat-resistant material such as a metal such as stainless steel or ceramics is inserted into the lumen in order to maintain the shape of the hollow fiber-shaped porous separation membrane. Then, the hot-melt resin is heated to a molten state, and as shown by the arrow in FIG. 1, the hot-melt resin is compressed by being pressed from the surroundings and the whole is narrowed down, as shown in FIG. As a result, the packing density of the hollow fiber-shaped porous separation membrane is improved, and a dense end sealing portion is formed.

The method of forming a preform having a terminal portion in which a hollow fiber-shaped porous separation membrane having a low filling factor and a sealing agent are integrated in advance is as follows: (1) One end of the hollow fiber-shaped porous separation membrane is A method of bundling a large number of heat-fusible resin molded products (for example, tube-shaped molded products) having holes that can be inserted, and (2) a heat-fusible resin having many holes into which one end of a hollow fiber-shaped porous separation membrane can be inserted. A method of inserting a large number into a resin molded product, or (3) a method of injection molding or extrusion molding in which a hot-melt resin is melted and poured into the gaps of a large number of hollow fiber-like porous separation membranes, (4) hollow fiber-like porous separation A method in which a powdery, granular, or pellet-like heat-fusible resin is put into a mold containing a film bundle and then heated and melted is used.
Among these, the methods (1) and (2), in which a hot-melt resin molded product is formed, are particularly preferable because they are easy to operate and do not enclose air bubbles in the resin.

Unlike the conventional method, the method of forming these preforms can be easily carried out because the gap between the hollow fiber-like porous separation membranes is relatively large. However,
The number of hollow fiber-shaped porous separation membranes used in the preform is
Number required for final filling rate.

In the preform, the cross-sectional area of the portion forming the end sealing portion is large, and may contain voids or air bubbles. In order to form a dense end sealing portion having a desired cross-sectional area and shape by narrowing this, for example, an apparatus as shown in FIG. 3 is used.

The preform is inserted into the concave portion of the receiving portion 4 shown in FIG. 3, and while the hot melt resin (sealing agent) is in a molten state by heating, pressure is applied to the moving portion 3 to remove the hot melt resin. When narrowing down, as shown in FIG. 4, the cross-sectional area of the end sealing portion is reduced. While the sealant is being heated and melted, it is molded under pressure to reduce it to a desired size. That is, the sealant between the separation membranes is narrowed down. At this time, it is necessary to provide a place where the squeezed sealant escapes, but this can be done by providing a hole in the peripheral wall of the pressurizing device, or by sealing up or down at the time of pressurization. In consideration of the amount of the agent, the height of the sealant in the preform may be lower than the final desired height.

According to this method, for example, a tube-shaped or pipe-shaped sealant may be covered on the end of the separation membrane without forming a terminal part having a low filling rate which is completely integrated originally. Even if a large number of are bundled together, the gaps and bubbles generated between the sealants or between the sealant and the separation membrane escape upward by the narrowing, so that they can be finally integrated. This method is simple, convenient, and useful.

The thus obtained hollow fiber bundle having a terminal sealing portion is usually inserted into an outer cylinder 5 as shown in FIG. 5 in order to form a hollow fiber-like porous separation membrane element, and then the end portion is formed. It is cut (FIG. 6) and the support rod is pulled out to make an element (FIG. 7). In this element, an end sealing portion having a shape in which a hot-melt resin invades a minute gap between the hollow fiber-shaped porous separation membranes and a minute gap between the hollow fiber-shaped porous separation membrane and the outer cylinder is formed. (FIG. 8).

The hollow fiber-like porous separation membrane used in the present invention is not particularly limited, but in particular, one made of a fluororesin such as PTFE (polytetrafluoroethylene) hollow fiber can be suitably used. Examples of the material of the element outer cylinder such as a cylindrical shape include metals such as stainless steel having excellent heat resistance and chemical resistance, and fluorine resins such as PTFE, FEP, and PFA (tetrafluoroethylene / perfluoroalkylvinyl ether copolymer). Is preferred.

The hot-melt resin used as a sealant in the present invention includes, for example, FEP, PFA, ETF
E (ethylene / tetrafluoroethylene copolymer), P
CTFE (polychlorotrifluoroethylene), PVd
A heat-fusible fluororesin such as F (polyvinylidene fluoride) can be used. Among them, FEP and PFA are most suitable from the viewpoint of heat resistance based on the resistance to steam sterilization and chemical resistance to acids, alkalis and solvents.

The combination of a fluororesin hollow fiber-shaped porous separation membrane and a hot-melt resin used as a sealant is preferably as high as possible in combination, and is preferably the same kind of resin. For example, when PTFE hollow fiber is used, FEP or PFA is most suitable as a sealant. In the case of a combination of different types and isomers, it is desirable to treat the surface of the hollow fiber to increase the affinity as much as possible.

The hollow fiber-like porous separation membrane element produced by the production method of the present invention can maintain the same hollow fiber filling ratio of 50 to 60% as the conventional product.

The manufacturing method according to the present invention is superior to the conventional method in the following points. (1) It is easy to mold the hot-melt resin into a molded article having a hole such as a tube in advance. Also, when molding a resin having a honeycomb-shaped through-hole in advance, holes are formed at a low density in a cylindrical or flat-shaped molded resin of the heat-meltable resin. Molding is easy even with conductive resins.

(2) If the heat-meltable resin of the sealing agent is previously processed and molded from a bulk state, the sealing is complete without bubbles. In addition, bubbles and voids can be eliminated by heating and pressing.

(3) At the time of sealing and molding, instead of applying pressure to a resin having a high viscosity and poor fluidity to cause it to penetrate into fine pores, a pressure is applied to an integrated body of the hollow fiber and the resin under heating. ,
There is no need for high pressure or strong force, as it only deforms.

Therefore, in the production method of the present invention, a heat-meltable fluororesin, which has conventionally been considered to be difficult to finely mold due to its high viscosity, is used as a sealant at the end of the hollow fiber-shaped porous separation membrane element. Can be used,
The heat resistance and the chemical resistance can be greatly improved as compared with a conventionally used epoxy resin, silicone resin, urethane resin or the like using a sealing agent. In particular, when FEP or PFA is used as the hot-melt resin, it can be used for separation and concentration using a strongly acidic or strongly alkaline solution or any solvent as a solvent, and can be repeatedly subjected to steam sterilization. A possible hollow fiber-like porous separation membrane element is obtained.

[0030]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to only these Examples.

Example 1 As a hollow fiber-shaped porous separation membrane, a porosity of 65%, an average pore diameter of 0.8 μm, and an inner diameter of 2 mm were used.
PTFE (polytetrafluoroethylene) with an outer diameter of 3 mm
A porous tube was used. FEP as terminal sealant
A 95 mm × 95 mm square made of (tetrafluoroethylene / hexafluoropropylene copolymer)
mmφ semicircle attached to the left and right (oval shape) and height 1
A 0 mm molded product was prepared, and 630 3 mmφ through-holes were formed almost uniformly perpendicular to the oval surface of the FEP molded product.

On the other hand, the PTFE tube has two lumens inside.
A stainless steel (SUS304) having a diameter of mmφ was inserted, and both ends were tied up with wires and sealed.
It was inserted into the hole of the EP molded product, and it was made to look like a flower just on the mountain.

This PTFE tube / FEP integrated product (preformed product) is put into a concave portion of a metal device having a shape shown in FIG.
This was heated to 290 ° C. When the FEP is in a molten state, the moving section 3 is gradually moved for about 6 hours,
Finally, as shown in FIG. 4, the PTFE tube / FEP
The integrated product was transformed from an oval shape to a 95 mmφ circle. After performing this operation for both ends of the tube,
This was inserted into a stainless steel element outer cylinder of mmφ.

With the end of the sealing portion slightly protruding from the outer cylinder, the outer cylinder was heated and fused with FEP (FIG. 5). Then, the portion protruding from the outer cylinder is cut and removed (FIG. 6),
The internal stainless steel rod was pulled out (FIG. 7). Similarly, the other end was formed to produce a cross-flow type internal pressure type hollow fiber porous separation membrane element.

Example 2 3 m inner diameter was used as a terminal sealant.
A FEP tube having a diameter of 4 mm, an outer diameter of 4 mm, and a length of 15 mm was used.
A cross-flow type internal pressure type hollow fiber-like porous separation membrane element was produced in the same manner as in Example 1, except that 600 FE porous tubes were bundled and used at the ends.

In the elements obtained in Examples 1 and 2 above, no bubbles were observed in the resin at the end sealing portion, and the adhesion between the sealing resin and the hollow fiber and the outer cylinder was good. Was. In addition, there was no penetration of the sealing resin into the hollow fiber lumen.

[Comparative Example 1] The same hollow fiber-shaped porous separation membrane, element outer cylinder and stainless steel rod as in Example 1 were used. A stainless steel rod was inserted into the hollow fiber-shaped porous separation membrane lumen, and 586 bundled with both ends fixed with wires were placed in an element outer cylinder which was set upright on a pan with an inner diameter of 95 mmφ × 10 mm height. At that time, powder FEP (manufactured by Daikin, NEOFLON FEP) was previously placed in the outer cylinder so as to have a height of 80 mm from the bottom. 3 in this state
After placing in a hot air thermostat at 00 ° C. and allowed to stand for one week, the temperature was returned to room temperature, the tray was removed, the FEP portion protruding from the element outer cylinder was cut off, and the inserted stainless steel rod was removed.

The other end of the hollow fiber is heat-sealed and sealed, and the outer cylinder at the heat-sealed end is sealed with a stainless steel lid.
A closed hollow fiber-shaped porous separation membrane element was obtained. In the obtained hollow fiber-shaped porous separation membrane element, a large number of bubbles were observed in the resin at the terminal sealing portion, and there was a portion without any sealing resin in the hollow fibers or between the hollow fibers and the outer cylinder. .

Comparative Example 2 95 mm
A cylindrical FEP resin molding having a height of φ × 40 mm was used. This is fixed with a vise and a drill (drill blade diameter, 2.
Attempting to open 586 through-holes in a honeycomb shape (lotus-shaped) at 8 mm), a number of portions where the holes were connected were generated. Insert a 2mmφ stainless steel rod into this hole.
After inserting 586 fixed hollow fiber-shaped porous separation membranes,
With the pan attached, it was placed in the vertical element outer cylinder.

The outer cylinder and the pan are heated with a band heater for 30 minutes.
By heating to 0 ° C., the FEP molded product was brought into a molten state. The band heater was turned off and allowed to stand naturally until it returned to room temperature. After that, the tray was removed, the FEP molded part protruding from the outer cylinder and the end of the hollow fiber in which the stainless steel rod was inserted into the hollow fiber lumen were cut off at the outer cylinder end face, and the inserted stainless steel rod was pulled out. In the obtained hollow fiber-shaped porous separation membrane element, a large number of bubbles are seen in the resin of the terminal sealing portion,
There were portions where no sealing resin was present between the hollow fibers or between the hollow fibers and the outer cylinder.

Comparative Example 3 Inner diameter 95 mm, depth 20 mm
A hole having a diameter of 10 mm was formed on the side surface of the receiving pan of Example 1 and used as a receiving pan, and the same hollow fiber-shaped porous separation membrane, stainless steel rod, and outer cylinder as in Example 1 were set.

While the outer cylinder and the tray were heated to 300 ° C., a molten FEP resin was injected into the tray and the outer cylinder from a melt extruder connected to the tray with a 10 mmφ pipe. The injection was 354 ml in total (95 mmφ × 50 mm
Equivalent) in about 1 hour. After finishing, another 24 hours,
After maintaining the temperature at 300 ° C. and removing the pan, the same operation as in Comparative Example 2 was carried out, but the FEP resin was not injected between the hollow fibers and the end of the outer cylinder opposite to the hole of the pan. The stop could not be made.

Comparative Example 4 Using the same hollow fiber-shaped porous separation membrane as in Example 1, an element having an end sealing portion made of an epoxy resin was prepared in the following steps. The both ends of the 586 hollow fiber-shaped porous separation membranes are heat-sealed and sealed, and 3 to 5 cm of the ends are coated with a fluororesin surface modifier (manufactured by Junko Co., tetra-etch).
After the treatment, 100 parts by weight of an epoxy resin (manufactured by Ciba-Geigy: CY-205 and HY-9) are used instead of FEP.
74J 23 parts by weight) was heated to 50 ° C.
4 ml were injected in 15 minutes.

Thereafter, at 75 ° C. for 3 hours, and further at 120 ° C.
For 2 hours to cure the epoxy resin. The tray was removed and the epoxy resin portion protruding from the outer cylinder was cut to obtain a hollow fiber-shaped porous separation membrane element having a structure in which the sealing agent was an epoxy resin. In the obtained hollow fiber-shaped porous separation membrane element, no bubbles were observed in the resin at the terminal sealing portion.

<Measurement of Physical Properties> Examples 1 and 2 An air leak test was performed at 0.2 kg / cm ² using the hollow fiber-shaped porous separation membrane elements obtained in Examples 1 and ^2. Was not recognized, and it was confirmed that the terminal sealing was completely performed. Further, using the hollow fiber-shaped porous separation membrane element obtained in Examples 1 and ² , under the conditions of a transmembrane pressure difference of 4 kg / cm ² and 400 hours,
After performing each filtration test of water, 40% ammonia water, 10% hydrochloric acid, acetone, toluene, diethylamine, and methylene chloride, an air leak test was performed again. As a result, no air leak was observed.

The hollow fiber-like porous separation membrane elements obtained in Examples 1 and 2 were immersed in concentrated sulfuric acid, 20% caustic soda, and 10% nitric acid for 3 months, and then subjected to an air leak test and a 5 kg / cm ² pressure resistance test. However, no air leak was observed.

Further, the hollow fiber-shaped porous separation membrane element obtained in Examples 1 and 2 was used at 150 ° C. and 10% humidity.
After heating at 0% for 1 hour, rapidly cooling, holding at 4 ° C. for 1 hour, and then heating again to 150 ° C., a heat cycle test was performed for 1 hour.
After 5 months, air leak test and 5kg / cm
^{2 When a} pressure resistance test was performed, no air leak was observed.

Comparative Examples 1 to 3 In contrast, an air leak test was performed at 0.2 kg / cm ² using the hollow fiber-shaped porous separation membrane elements obtained in Comparative Examples 1 and ^2. An air leak was observed. In Comparative Example 3, as described above, a satisfactory end sealing portion could not be produced, and thus no air leak test was performed.

Comparative Example 4 An air leak test was performed at 0.2 kg / cm ² using the hollow fiber-shaped porous separation membrane element obtained in Comparative Example 4, and no air leak was observed. However, under the conditions of a transmembrane pressure difference of 4 kg / cm ² and 400 hours,
After performing each filtration test of water, 40% ammonia water, 10% hydrochloric acid, acetone, toluene, diethylamine and methylene chloride, an air leak test was again performed. As a result, filtration of 40% ammonia water, acetone, diethylamine and methylene chloride was performed. Cracks and air leaks at the end sealing portion were observed. In particular, after the filtration test of diethylamine and methylene chloride, many cracks and partial defects were observed in the terminal sealing portion.

After immersion in concentrated sulfuric acid, 20% caustic soda and 10% nitric acid for 3 months, an air leak test and a 5 kg / cm ² pressure resistance test were carried out. . Further, in the heat cycle test, the end sealing portion was broken within one day.

[0051]

The hollow fiber porous separation membrane element according to the production method of the present invention has improved heat resistance and chemical resistance, and has a complete end seal, so that an acidic or alkaline solution or an organic solvent can be used as a solvent. It is suitable for use in washing or the like, or for a separation membrane module requiring sterilization or sterilization such as steam sterilization.

The method for producing a hollow fiber-shaped porous separation membrane element of the present invention greatly improves the fine moldability of the end sealing portion. Therefore, even if a high-viscosity heat-meltable fluororesin is used as a sealing agent, a hollow fiber-shaped porous separation membrane element with a high filling rate can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing one embodiment of a preform having a terminal filling portion of a hollow fiber-shaped porous separation membrane formed at a low filling rate.

FIG. 2 is a schematic cross-sectional view showing a terminal sealing portion formed by heating and pressing a preform into a desired shape.

FIG. 3 is a schematic view showing an example of an apparatus used in the manufacturing method of the present invention.

FIG. 4 is a schematic view showing that the moving part of the apparatus of FIG. 3 has been moved to pressurize the preform.

FIG. 5 is a schematic view showing an outer cylinder mounting step in a stage of finishing as an element in the manufacturing method of the present invention.

FIG. 6 is a schematic view showing a step of cutting and removing a terminal portion of a sealing portion.

FIG. 7 is a schematic view showing the element after the stainless steel bar of the sealing portion is extracted.

FIG. 8 is a schematic view showing an example of a cross section of an end portion of a hollow fiber-shaped porous separation membrane element obtained by the production method of the present invention.

[Explanation of symbols]

 1 PTFE porous tube with stainless steel rod inserted 2 Heat-meltable resin sealant 3 Moving part 4 Preformed product receiving part 5 Stainless steel outer cylinder 6 Stainless steel rod 7 PTFE porous tube

Claims (3)

(57) [Claims] 1. A preform having a shape in which one end of a number of hollow fiber-like porous separation membranes is inserted into a hot-melt resin is prepared, and then the hot-melt resin of the preform is heated to a molten state. A hollow fiber-like porous separation membrane characterized in that the gap between the hollow fiber-like porous separation membranes is reduced by applying pressure from the surroundings to form a terminal sealing portion made of a heat-meltable resin in a desired shape. Element manufacturing method. 2. A pre-molded product obtained by bundling a large number of hollow fiber-shaped porous separation membranes each having one end inserted into a hot-melt resin molded product having a hole into which the hollow fiber-shaped porous separation membrane can be inserted. By applying pressure from the surroundings while in a state,
Each of the heat-fusible resin molded products into which the hollow fiber-shaped porous separation membranes are inserted is melt-integrated, and at the same time, the gap between the hollow fiber-shaped porous separation membranes is reduced to form a terminal sealing portion made of a heat-meltable resin having a desired shape. The method for producing a hollow fiber-shaped porous separation membrane element according to claim 1, wherein 3. The pre-molded product is obtained by inserting one end of a hollow fiber-shaped porous separation membrane into a hot-melt resin molded product having a large number of holes into which the hollow fiber-shaped porous separation membrane can be inserted. 2. The hollow fiber according to claim 1, wherein the pressure is applied from the periphery to reduce the gap between the hollow fiber porous separation membranes, thereby forming a terminal sealing portion made of a heat-meltable resin having a desired shape. A method for producing a porous separation membrane element.