porous hollow fiber membrane

A hollow fiber membrane and hollow technology, applied in the field of porous hollow fiber membrane, can solve the problems of difficult membrane production process, high manufacturing cost, and many factors of membrane production conditions, and achieve excellent physical durability, excellent chemical durability, and high-purity water permeability. over performance effect

Active Publication Date: 2018-06-12
TORAY IND INC
View PDF11 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] However, the wet solution method has the following problems: it is difficult to cause phase separation uniformly in the film thickness direction, and a film with an asymmetric three-dimensional network structure including macropores is formed, so the strength is insufficient.
In addition, there are disadvantages that there are many film-forming condition factors that affect the film structure and film performance, so it is difficult to control the film-forming process and lacks reproducibility.
However, the strength is insufficient, and if the dispersibility of the inorganic fine particles is poor, there is a possibility of defects such as pinholes
In addition, the melt extraction method also has the disadvantage that the manufacturing cost is very high

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • porous hollow fiber membrane
  • porous hollow fiber membrane
  • porous hollow fiber membrane

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0140] (2-1) Preparation of membrane stock solution

[0141] The method for producing a porous hollow fiber membrane in the present invention further includes a step of preparing a fluororesin polymer solution. By dissolving the fluororesin polymer in a poor solvent or a good solvent of the fluororesin polymer at a relatively high temperature above the crystallization temperature, a fluororesin polymer solution (that is, a film-forming film containing the fluororesin polymer) is prepared. stock solution).

[0142] When the polymer concentration in the membrane-forming stock solution is high, a porous hollow fiber membrane having high strength can be obtained. On the other hand, when the polymer concentration is low, the porosity of the porous hollow fiber membrane increases and the pure water permeability improves. Therefore, the concentration of the fluororesin polymer is preferably not less than 20% by weight and not more than 60% by weight, more preferably not less than 3...

Embodiment 1

[0222] 36% by weight of a vinylidene fluoride homopolymer (KF1300 manufactured by KLEHA Co., Ltd., weight average molecular weight: 417,000, number average molecular weight: 221,000) and 64% by weight of γ-butyrolactone were dissolved at 150°C. The Tc of this vinylidene fluoride homopolymer solution was 48°C. This solution was pressurized to 2.0 MPa by installing two gear pumps, and the line between them was pressurized to 2.0 MPa, and it was retained at 99 to 101° C. for 20 seconds, and then it was discharged from the outer tube of the double-tube spinneret. Simultaneously, an 85% by weight aqueous solution of γ-butyrolactone is discharged from the inner tube of the double-layer tube spinneret, and is retained for 20 seconds in a cooling bath at a temperature of 25° C. formed by an 85% by weight aqueous solution of γ-butyrolactone. , to make it harden. The obtained porous hollow fiber membrane had a columnar structure with a thickness uniformity of 0.62, a columnar structure...

Embodiment 2

[0225] 36% by weight of a vinylidene fluoride homopolymer (KF1300 manufactured by KLEHA Co., Ltd., weight average molecular weight: 417,000, number average molecular weight: 221,000) and 64% by weight of γ-butyrolactone were dissolved at 150°C. The Tc of this vinylidene fluoride homopolymer solution was 48°C. The solution was pressurized to 2.0 MPa by installing two gear pumps, the line between them was pressurized to 2.0 MPa, and the solution was retained at 99 to 101° C. for 20 seconds, and then discharged from the outer tube of the double-tube spinneret. , Simultaneously, the 85% by weight aqueous solution of γ-butyrolactone is discharged from the pipe of the inner side of the double-tube spinneret, and stays in the 1st cooling bath of the temperature 5 ℃ that is formed by the 85% by weight aqueous solution of γ-butyrolactone After 10 seconds, the mixture was solidified by staying in a second cooling bath at a temperature of 25° C. consisting of an 85% by weight aqueous sol...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
lengthaaaaaaaaaa
breaking strengthaaaaaaaaaa
lengthaaaaaaaaaa
Login to view more

Abstract

An object of the present invention is to provide a porous hollow fiber membrane having high strength while maintaining high pure water permeation performance. The porous hollow fiber membrane of the present invention is a porous hollow fiber membrane comprising a fluororesin-based polymer, has a columnar structure oriented longitudinally of the porous hollow fiber membrane, and molecular chains of the fluororesin-based polymer are oriented longitudinally of the porous hollow fiber membrane.

Description

technical field [0001] The present invention relates to a porous hollow fiber membrane suitable for various water treatments such as drinking water production, industrial water production, water purification treatment, wastewater treatment, and seawater desalination. Background technique [0002] In recent years, porous membranes have been used in various fields such as water treatment fields such as water purification and wastewater treatment, medical applications such as blood purification, food industry fields, battery separators, charged membranes, and fuel cell electrolyte membranes. [0003] Especially in the field of drinking water production and industrial water production, that is, in the field of water treatment such as water purification treatment, drainage treatment and seawater desalination, as a substitute for the previous sand filtration, coagulation sedimentation, evaporation, etc., or in order to improve To treat water quality, porous membranes have been inc...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): B01D71/32B01D69/02B01D69/08B01D71/34
CPCB01D69/02B01D69/08B01D71/32B01D67/0016B01D67/0018B01D67/0027B01D2323/08B01D2325/02B01D2325/24B01D2325/30B01D2325/32B01D2325/34B01D67/0013B01D69/087B01D2323/10B01D71/34B01D2325/0281B01D67/00113
Inventor 花川正行岩井健太石崎利之北出有木村将弘
Owner TORAY IND INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products