Method for preparing hydrophilic porous membrane

A porous membrane and hydrophilic technology, which is applied in the field of post-treatment of ultrafiltration and microfiltration membranes, can solve the problems of membrane pore enlargement, loss of filtration function, and deterioration of effluent water quality, and achieve uniform membrane pore size and uniform membrane pore size. The effect of structural stability

Inactive Publication Date: 2010-10-20
XIAMEN LEEBAM MEMBRANE TECH
View PDF1 Cites 27 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] Among the many hydrophilic modifiers, polyvinylpyrrolidone (PVP) is widely used in polyvinylidene fluoride (PVDF), polysulfone (PSF), polyethersulfone (PES) and other porous materials due to its good compatibility. The blending modification of the membrane improves the hydrophilicity of the membrane surface, but during the long-term operation of the membrane, such substances are often washed out from the membrane body, and hypochlorite is used to treat PES / PVP, PSF / PVP, PAN / PVP or PVDF / PVP can greatly improve the membrane flux. This is because a large amount of PVP is dissolved, resulting in enlarged membrane pores, poor effluent quality, and gradual loss of filtration function.

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
  • Method for preparing hydrophilic porous membrane
  • Method for preparing hydrophilic porous membrane
  • Method for preparing hydrophilic porous membrane

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] Embodiment 1: prepare polymer film by known blending modification method, film-forming polymer is polyethersulfone (English abbreviation is PES), modification additive is polyvinylpyrrolidone (English abbreviation is PVP), PES concentration is 18%, the PVP concentration is 3%, stirring and dissolving at 90°C for 6h, standing for defoaming for 24h, scraping the membrane, and then chemically crosslinking the polymer membrane to obtain a hydrophilic porous membrane. The chemical crosslinking treatment is Soak the polymer film in ammonium persulfate solution at a temperature of 80°C, then take it out and put it into a glycerol solution with a concentration of 30% by weight, soak it for about 1 hour, and then dry it at room temperature. and soaking time are tested, then the membrane flux of the prepared porous membrane is detected, and the data in table 1 are obtained:

[0027] Table 1

[0028] sample number

[0029] The known polymer membrane has a membrane flux ...

Embodiment 2

[0030] Example 2: In the post-processing process of the water filtration membrane, it is often necessary to wet the membrane pores with glycerin to prevent the membrane pores from collapsing during the drying process. The porous membrane treated by cross-linking in Example 1 can be directly dried at room temperature without wetting with glycerin, and the dried porous membrane still maintains a high membrane flux. Table 2 shows the test results of polymer membranes made of polysulfone (abbreviated as PSF) and polyvinylpyrrolidone / vinyl acetate copolymer (PVP / VA) without glycerol treatment, and the polymer membranes were soaked in The cross-linking agent solution was used for half an hour, the temperature was controlled at 90 °C, and then the film was dried at room temperature.

[0031] Table 2

[0032] sample number

[0033]Based on the above results, it can be seen that glycerol has a great influence on the membrane flux without cross-linking treatment, but has litt...

Embodiment 3

[0034] Example 3: A polymer film is produced by a known blending modification method, wherein the film-forming polymer is polyvinylidene fluoride (English name abbreviated as PVDF), and the modification additive is polyvinylpyrrolidone (English abbreviated as PVP), Soak the prepared polymer membrane in ammonium persulfate aqueous solution with a concentration of 10% by weight at room temperature for different periods of time, then take it out and heat it to 100°C with steam for half an hour to test its membrane flux. The results are shown in Table 3 .

[0035] table 3

[0036] sample number

[0037] The test results show that sufficient soaking time is very necessary to improve the membrane flux.

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

No PUM Login to view more

Abstract

The invention provides a method for preparing a hydrophilic porous membrane. The method comprises the following steps of: preparing a polymer membrane by using a known blending modification method, wherein a membrane forming polymer is one of polyvinylidene fluoride, polysulfone, polyether sulphone, polrvinyl chloride, polyamide or polyacrylonitrile; a modification additive is one of or a mixture of more of polyvinylpyrrolidone, polyvinylpyrrolidone copolymer, polyethylene glycol, polypropylene glycol, polyvinyl alcohol, polyacrylic acid or polyelectrolyte; and then performing chemical crosslinking or radiation crosslinking treatment on the prepared polymer membrane to obtain the porous membrane with stable hydrophilicity. The prepared porous membrane has more uniform bore diameters, and the membrane flux is higher than that of the unprocessed membrane by 2 to 10 times.

Description

technical field [0001] The invention relates to the technical field of post-treatment of ultrafiltration and microfiltration membranes, and is especially suitable for blended membranes of hydrophobic / hydrophilic polymers. The method for preparing hydrophilic porous membranes provided by the invention mainly relates to the water flux and water flux of the porous membranes. Hydrophilic stability. Background technique [0002] With the progress of society and the improvement of people's quality of life, water pollution is increasing day by day, water sources are getting worse day by day, and there are more and more types of pollutants, especially organic pollutants. Traditional water treatment processes such as pre-chlorine oxidation, coagulation sedimentation, filtration, and disinfection have been unable to meet the water quality requirements. Membrane separation technology has become one of the most concerned water treatment technologies in recent years due to its excellent...

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 Applications(China)
IPC IPC(8): B01D71/06B01D67/00B01D69/02
Inventor 任以伟王俊川
Owner XIAMEN LEEBAM MEMBRANE TECH
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