JP2001219043A - Producing method of polyphenyl sulfone hollow fiber membrane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a producing method of hollow fiber membrane which is polysulfone type hollow fiber membrane excellent in chemical resistance at high temperature and detergent resistance and durable for high working pressure and is excellent in permeation performance. SOLUTION: In this producing method of hollow fiber membrane, spinning raw liquid comprising a water soluble organic solvent solution of polyphenyl sulfone and hydrophilic polyvinylpyrrolidone is used and the hollow fiber membrane is produced by a wet spinning method or a dry/wet spinning method, where the aqueous solution of N-methyl-2-pyrrolidone polymer is used as a core solution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyphenylsulfone hollow fiber membrane. More specifically, the present invention relates to a method for producing a polyphenylsulfone hollow fiber membrane suitably used as an ultrafiltration membrane for oil / water separation.

[0002]

2. Description of the Related Art Aromatic polymer compounds, particularly aromatic polysulfones, have relatively high heat resistance and chemical resistance, but have high chemical resistance and cleaning agent resistance at high temperatures and can withstand high working pressure. A hollow fiber membrane that can withstand time cannot be obtained. Further, membrane materials used for ultrafiltration membranes such as polysulfone show high resistance to ordinary hot water and the like, but some cleaning agents cause significant deterioration.

[0003] For example, in order to remove oil which has been emulsified and dispersed in a cleaning liquid containing a water-based cleaning agent, Parker product PK-7170, which is a typical water-based cleaning agent, is removed using an ultrafiltration membrane. In this case, when polysulfone is used as the material for the ultrafiltration membrane, it is impossible to avoid a phenomenon in which the membrane deteriorates during use, and eventually the membrane ruptures.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polysulfone-based hollow fiber membrane which has high chemical resistance at high temperatures and cleaning agent resistance and can withstand high use pressure for a long time.
An object of the present invention is to provide a production method which has excellent transmission performance.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
Using a spinning solution comprising a water-soluble organic solvent solution of polyphenylsulfone and hydrophilic polyvinylpyrrolidone, when producing a hollow fiber membrane by a wet spinning method or a dry-wet spinning method, an aqueous solution of N-methyl-2-pyrrolidone is used as a core liquid. Achieved by using

[0006]

DETAILED DESCRIPTION OF THE INVENTION Polyphenylsulfone is a repeating unit represented by the following: That is, it has a biphenylene group and no isopropylidene group, and a commercially available product, for example, a product of the Teijin Amoco RADEL R series can be used as it is.

A spinning solution containing polyphenylsulfone as a film-forming component is mixed with hydrophilic polyvinylpyrrolidone and a water-soluble organic solvent. In the present invention, N-methyl-2-pyrrolidone and dimethylformamide are used as water-soluble organic solvents. And the like, and preferably N-methyl-2-pyrrolidone from the viewpoint of spinning stability.

[0008] The spinning solution contains about 10% of polyphenyl sulfone.
About 30% by weight, preferably about 15 to 25% by weight, and polyvinyl pyrrolidone in a blending ratio of about 5 to 20% by weight, preferably about 8 to 12% by weight. % Or less, preferably about 1 to 5% by weight of water or ethylene glycol.

The formation of a polyphenylsulfone hollow fiber membrane using such a spinning stock solution is carried out by a wet spinning method or a dry-wet spinning method.
% Or less, preferably about 40-60% by weight of an aqueous solution of N-methyl-2-pyrrolidone. The use of such a core liquid
Improves the permeation performance of the polyphenylsulfone hollow fiber membrane. The spun hollow fiber membrane is coagulated in an aqueous coagulation bath (gelling bath) represented by water.

[0010]

The polyphenylsulfone hollow fiber membrane obtained by the method of the present invention is excellent in cleaning agent resistance and pressure resistance. It also does not cause rupture and other phenomena, and is also excellent in permeation performance, so that it can be effectively used as an ultrafiltration membrane for oil-water separation where washing with a detergent is repeated.

[0011]

Next, the present invention will be described with reference to examples.

EXAMPLES Polyphenyl sulfone (Amoco RADEL R-5000) 19.5
Parts by weight, polyvinylpyrrolidone (K-90) 9.5 parts by weight, pure water
A spinning stock solution consisting of 2.5 parts by weight and 68.5 parts by weight of N-methyl-2-pyrrolidone was placed in a water coagulation bath from a double annular nozzle by a wet spinning method using a 50% by weight aqueous solution of N-methyl-2-pyrrolidone as a core solution. After discharging and gelling, it was passed through a washing tank containing water at 45 ° C. and wound around a bobbin.

The obtained polyphenylsulfone hollow fiber membrane
(Outer diameter: 1.4 mm, inner diameter: 0.8 mm), a simultaneous test of cleaning agent resistance and pressure resistance was performed. The tests were conducted with representative water-based cleaning agents, Henkel White Water Product NB-10 and Parker Product PK-7170.
Or 10% by weight of Daiichi Kogyo Pharmaceutical's DK Beakrya CW5524
Using an aqueous solution, the membrane inlet pressure 3Kgf / cm ² (0.3MPa), the membrane outlet pressure 2Kgf / cm ² (0.2MPa) at 80 ° C. by passing the detergent aqueous solution through the hollow fiber membrane for 12 hours, No rupture was observed in the hollow fiber membrane in any case.

Comparative Example 1 In the Examples, polysulfone (UDEL P-3500 manufactured by Amoco) was used in place of polyphenylsulfone, and dimethylformamide was used in the same amount in place of N-methyl-2-pyrrolidone. Was used as pure water. In a simultaneous test of detergent resistance and pressure resistance of the obtained polysulfone hollow fiber membrane, no membrane rupture was observed for NB-10, but for PK-7170 within 8 hours, and CW-5
For 524, the rupture of the hollow fiber membrane was observed within 4 hours.

Comparative Example 2 In Example, pure water was used as a core liquid instead of a 50% by weight aqueous solution of N-methyl-2-pyrrolidone. Inlet pressure
0.9 kgf / cm ² (0.09 MPa), membrane outlet pressure 1.1 kgf / cm ² (0.11 MPa
a) was performed under the condition of 25 ° C. Pure water flux is 50% N
-Methyl-2-pyrrolidone aqueous solution using 10 ml / c
While m was ² · hr or more, those with pure water core liquid
It was ^{2 to 5} ml / cm ² · hr.

Claims (4)

[Claims] An N-methyl-2-pyrrolidone for producing a hollow fiber membrane by a wet spinning method or a dry-wet spinning method using an undiluted spinning solution comprising a solution of polyphenylsulfone and hydrophilic polyvinylpyrrolidone in a water-soluble organic solvent. A method for producing a polyphenylsulfone hollow fiber membrane, comprising using an aqueous solution as a core liquid. 2. The method for producing a polyphenylsulfone hollow fiber membrane according to claim 1, wherein N-methyl-2-pyrrolidone is used as the water-soluble organic solvent. 3. The method for producing a polyphenylsulfone hollow fiber membrane according to claim 2, wherein a spinning solution containing about 10% by weight or less of water or ethylene glycol is used. 4. An ultrafiltration membrane for oil / water separation, comprising a polyphenylsulfone hollow fiber membrane produced by the method according to claim 1, 2 or 3.